A semiconductor apparatus includes a wiring pattern, an insulating film, and a thin-metal-film resistor element. The insulating film is formed on the wiring pattern having connection holes vertically penetrating there-through to expose part of the wiring pattern at bottom regions of the connection holes. The connection holes are arranged with a space there-between. The thin-metal-film resistor element is formed on the insulating film and extending to continuously overlay and contact surfaces of the insulating film, inner walls of the connection holes, and the wiring pattern at the bottom regions of the connection holes.

Conventionally, resistor elements are important elements and are widely used in an analog integrated circuit. Amongst various resistor elements, a resistor element made of a thin metal film (hereinafter referred to as a thin-metal-film resistor element) has become a focus of attention in recent years because its temperature coefficient of resistance (TCR), that is, a temperature dependency, is relatively low. The thin-metal-film resistor element is made of any one of materials including CrSi, NiCr, TaN, CrSi2, CrSiN, and CrSiO, for example.
In a semiconductor apparatus having the thin-metal-film resistor element, a higher sheet resistance is aimed so as to meet a demand for a high-integration design. In many cases, the thin-metal-film resistor element is formed with a thickness of 1000 Å or thinner in a semiconductor apparatus.
There are several methods for making an electrical connection to the thin-metal-film resistor element. For example, a first method is to connect a metal wiring directly to the tin-metal-film resistor element. A second method is to form an interlayer insulating film after the thin-metal-film resistor element is formed, to form a connection hole in the interlayer insulating film, and to connect a metal wiring to the thin-metal-film resistor element via the connection hole. A third method is to form a barrier film on a layer of the thin-metal-film resistor element and to connect a metal wiring to the barrier film.
Referring to FIGS. 1A-1F, an exemplary process of the above-mentioned first method is explained. FIGS. 1A-1F illustrate cross-sections of a semiconductor apparatus in respective steps of production which are sequentially conducted. Before the step of FIG. 1A, a silicon substrate 1 in a wafer state is provided. On the silicon substrate 1, formations of an element-separation oxide film 3 and other elements (not shown) including a transistor element (not shown) have been completed. Then, in the step of FIG. 1A, a BPSG (borophosphosilicate glass) film is formed on the silicon substrate 1 and is subjected to a reflow process. The BPSG film is to become a first interlayer insulating film 5 between a gate electrode of the transistor and the metal wiring.
In the step of FIG. 1B, a thin metal film 73 is formed, on the silicon substrate 1, to a thickness in a range of approximately 25 Å to approximately 500 Å. The thin metal film 73 is to form the thin-metal-film resistor element.
In the step of FIG. 1C, a resist pattern 75 is formed on the thin metal film 73. The resist pattern 75 is used to determine a formation region of the thin-metal-film resistor element. Then, by using the resist pattern 75 as a mask, the thin metal film 73 is subjected to a patterning process to form a thin-metal-film resistor element 77.
In the step of FIG. 1D, the resist pattern 75 is removed and then a metal film 79, made of an AlSiCu film, for use in wiring is formed on the surfaces of the thin-metal-film resistor element 77 and the first interlayer insulating film 5. Subsequently, a resist pattern 81 is formed on the metal film 79 so as to pattern the metal film 79 such that part of the metal film 79 remains at two opposite edges of the thin-metal-film resistor element 77.
In the step of FIG. 1E, using a wet etching technique, the metal film 79 is patterned with a mask of the resist pattern 81 so as to form a metal wiring pattern 83. For the etching treatment to the metal film 79 for use in wiring, a dry etching technique is usually used in a general production process of a semiconductor apparatus; but when the thin-metal-film resistor element 77, having a very thin thickness is laid immediately under the metal film 79, the dry etching technique cannot be used because the thin-metal-film resistor element 77 is etched with an over-etching. Therefore, it is necessary to use the wet etching technique to pattern the metal film 79.
In the step of FIG. 1F, by removing the resist pattern 81, the formations of the thin-metal-film resistor element 77 and the metal wiring pattern 83 for making an electrical connection to the thin-metal-film resistor element 77 are completed.
Referring to FIGS. 2A-2F, an exemplary process of the above-mentioned second method is explained. FIG. 2A illustrates a step in which the element-separation oxide film 3, the first interlayer insulating film 5, and the thin-metal-film resistor element 77 are formed on the silicon substrate 1 in a manner similar to the above-described steps of FIGS. 1A-1C.
In the step of FIG. 2B, a CVD (chemical vapor deposition) oxide film 85 with a thickness on the order of 8500 Å for serving as an interlayer insulating film to insulate from the metal wiring is formed on the surfaces of the thin-metal-film resistor element 77 and the first interlayer insulating film 5.
In the step of FIG. 2C, a resist pattern 87 having openings in regions corresponding to two opposite edges of the thin-metal-film resistor element 77 is formed on the CVD oxide film 85 so as to form connection holes to make a connection to the metal wiring. By using the wet etching technique, the CVD oxide film 85 is selectively removed with a mask of the resist pattern 87 and, as a result, connection holes 89 are prepared. The dry etching technique is usually used to form the connection holes 89 in a general production process of a semiconductor apparatus but when the thickness of the thin-metal-film resistor element 77 is thinner than 1000 Å, the wet etching technique is needed to form the connection holes 89, because it becomes difficult to prevent the connection holes 89 from penetrating the thin-metal-film resistor element 77.
In the step of FIG. 2D, a metal film 91 made of an AlSiCu film for use in wiring is formed on the surfaces of the CVD oxide film 85 and inner walls of the connection holes 89.
In the step of FIG. 2E, a resist pattern 93 is formed on the metal film 91 so as to pattern the metal film 91 such that part of the metal film 91 remains at two opposite edges of the thin-metal-film resistor element 77.
In the step of FIG. 2F, using the dry etching technique, the metal film 91 is patterned with a mask of the resist pattern 93 so as to form a metal wiring pattern 95. At this time, because the CVD oxide film 85 is formed underneath the metal film 91, the thin-metal-film resistor element 77 will not be etched by the dry etching process.
Subsequently, the resist pattern 93 is removed so that the formations of the thin-metal-film resistor element 77 and the metal wiring pattern 95 for making an electrical connection to the thin-metal-film resistor element 77 are completed.
Referring to FIGS. 3A-3F, an exemplary process of the above-mentioned third method is explained. FIG. 3A illustrates a step in which the element-separation oxide film 3, the first interlayer insulating film 5, and the thin-metal-film resistor element 77 are formed on the silicon substrate 1 in a manners similar to the above-described steps of FIGS. 1A-1C.
In the step of FIG. 3B, a high-melting-point metal film 97 made of materials such as TiW or the like, to serve as a barrier from the metal wiring, is formed on the surfaces of the thin-metal-film resistor element 77 and the first interlayer insulating film 5. Subsequently, a metal film 99 for use in wiring is formed on the high-melting-point metal film 97. The metal film 99 is made of an AlSi film, an AlSiCu film, or the like.
In the step of FIG. 3C, a resist pattern 101 is formed on the metal film 99 so as to pattern the metal film 99 such that part of the metal film 99 remains at two opposite edges of the thin-metal-film resistor element 77.
In the step of FIG. 3D, using the dry etching technique, the metal film 99 is patterned with a mask of the resist pattern 101 so as to form a metal wiring pattern 103. At this time, since the high-melting-point metal film 97 is formed underneath the metal film 99, the thin-metal-film resistor element 77 will not be etched by the dry etching process.
In the step of FIG. 3E, the resist pattern 101 is removed and then, by using the wet etching technique, the high-melting-point metal film 97 is selectively removed with a mask of the metal wiring pattern 103 so that a high-melting-point metal film pattern 105 is prepared. Thereby, the formations of the thin-metal-film resistor element 77, the metal wiring pattern 103 for making an electrical connection to the thin-metal-film resistor element 77, and the high-melting-point metal film pattern 105 are completed. In this step, the patterning of the high-melting-point metal film 97 with the dry etching process is difficult since the high-melting-point metal film 97 is present immediately above the thin-metal-film resistor element 77.
There is known another conventional semiconductor apparatus in which a resistor element is formed on an uppermost layer wiring electrode through an insulating film and is connected to the uppermost layer wiring electrode, although the resistor element in this case is not in a shape of a thin metal film. In this semiconductor apparatus, the resistor element and the wiring electrode seem to connect to each other with their side surfaces. This side surface connection may be extremely difficult to be materialized in a general semiconductor device manufacturing process. In addition, even if such side surface connection is materialized, when the resistor element is a thin-metal-film resistor element, a contact area between the resistor element and the wiring electrode would be considerably small, which would consequently generate a great amount of contact resistance there between. As a result, this type of semiconductor apparatus may not properly function as electrical circuitry.
In the first method, the patterning of the metal film 79 for use in wiring is difficult with the dry etching technique, in the step of FIG. 1E. This causes a problem of interfering with the high degree of circuitry integration.
Also, the thin-metal-film resistor element 77 is likely to be oxidized in general. Therefore, if the metal film 79 for use in wiring is formed under the condition that the surface of the thin-metal-film resistor element 77 is oxidized, it becomes difficult to make a good electrical connection between the thin-metal-film resistor element 77 and the metal wiring pattern 83. In a general production process of a semiconductor apparatus, a preferable electrical connection is made between the silicon substrate and the metal wiring by removing the naturally-oxidized film from the surface of the silicon substrate with a hydrofluoric acid aqueous solution, for example. The thin-metal-film resistor element 77, however, is easily etched by the hydrofluoric acid aqueous solution. Accordingly, if a removal of an oxide film is performed with the hydrofluoric acid aqueous solution before the metal film 79 is formed in the step of FIG. 1D, the thin-metal-film resistor element 77 may be etched by the hydrofluoric acid aqueous solution.
As a result, it may cause a problem of changing the resistance of the thin-metal-film resistor element 77.
The second method prepares the CVD oxide film 85 on the thin-metal-film resistor element 77 so as to allow the dry etching process to be used in the step of FIG. 2F for the patterning of the metal film 91 for use in wiring. However, the connection holes 89 for making an electrical connection between the thin-metal-film resistor element 77 and the metal wiring pattern 95 are, as described above, needed to be formed with the wet etching process in the step of 2C, which interferes miniaturization of circuitry, that is, a high degree of circuitry integration.
Further, the above-mentioned wet etching process uses the hydrofluoric acid aqueous solution, which etches the thin-metal-film resistor element 77 and therefore, additional measures are required to prevent the etching of the thin-metal-film resistor element 77 with the hydrofluoric acid aqueous solution, in which a barrier film is formed and is patterned on the thin-metal-film resistor element 77. This causes a problem of increasing the steps of the production process.
The third method allows the dry etching to be performed to etch the metal film for use in wiring, as described in the step of FIG. 3D and, in addition, it eliminates the formation of the connection holes. This method, however, needs to pattern the high-melting-point metal film 97 with the wet etching, as described in the step of FIG. 3E. In this method, the high-melting-point metal film 97 is used to form the high-melting-point metal film pattern 105 for determining a substantial length of the thin-metal-film resistor element 77. Accordingly, an area of the high-melting-point metal film 97 etched with the wet etching falls wider than a desired area, resulting in a variation of the substantial length of the thin-metal-film resistor element 77. As a consequence, the resistance of the thin-metal-film resistor element 77 is changed and at the same time, the miniaturization of the circuitry becomes difficult.
Further, in the step of FIG. 3B, the surface of the thin-metal-film resistor element 77, which has been formed before the high-melting-point metal film 97, is likely oxidized. Accordingly, such oxide film formed on the thin-metal-film resistor element 77 is needed to be removed with the hydrofluoric acid aqueous solution, in order to make a good electrical connection between the thin-metal-film resistor element 77 and the high-melting-point metal film 97. However, as described above, if a removal of an oxide film is performed with the hydrofluoric acid aqueous solution before the high-melting-point metal film 97 is formed, the thin-metal-film resistor element 77 may be etched by the hydrofluoric acid aqueous solution. As a result, it may cause a problem of changing the resistance of the thin-metal-film resistor element 77.
As such, the conventional methods inevitably require the wet etching technique due to the thinness of the thin-metal-film resistor element, and therefore, cannot avoid the variations of resistance of the thin-metal-film resistor element, resulting in interfering a high degree of circuitry integration.
Further, these conventional methods require an additional step for forming a barrier film on the thin-metal-film resistor element and an extra treatment to remove the surface oxidized film with the hydrofluoric acid aqueous solution, in order to make a good electrical connection of the thin-metal-film resistor element to the metal wiring.

Semiconductor apparatus including a thin-metal-film resistor element and a method of manufacturing the same


A method and system for sending information in the form of a wireless message to a wireless device subscriber requesting advertising, product, or service information is described. The method includes assigning an information request code by a service provider to the information provided by an advertiser, presenting or displaying the information request code along with an advertisement to potential consumers, receiving the information request code from the wireless device, and sending a wireless message to the potential consumer's wireless communication device. The system includes an advertisement comprising an information request code, a wireless communication device operable for sending the information request code and receiving a wireless data message, a wireless communication center in communication with a wireless network and operable for relaying, storing, and forwarding the wireless data message to the wireless communication device.

1. Field of the Invention
This invention relates generally to the field of wireless communications. More particularly, this invention relates to methods and systems in which a wireless service provider may offer wireless data messages to mobile subscribers including detailed product, service, and promotional information.
2. Description of the Related Art
Effective advertising can dramatically increase revenue levels for all types of businesses. Advertisers utilize a variety of forms and mediums to convey their message, including written words on a billboard, spoken words transmitted over the radio, and commercials broadcast during pre-selected breaks in the broadcast of a television program. As the Internet has grown, so has advertisers utilization of this new medium. "Pop-up" and "pop-under" windows are well known to the average Internet user. Because of the popularity of such advertising, at least to the advertisers, many Internet service providers and search engine companies are able to offer free services to consumer, supporting these services solely or at least primarily with advertising dollars.
Advertising is typically most effective when information is presented in a clear and informative manner and targeted towards specific groups of potential consumers. Targeted advertising refers to a method in which an advertiser identifies a group of consumers as those likely to purchase an advertised product or service. For example, advertisers often gather demographic data related to audiences of specific television programming and tailor advertising campaigns around the demographics. Advertisers approach billboard advertising in a similar manner. For example, advertises often use billboards as a medium for advertising new automotive products, including the automobiles themselves. Because of the location of billboards along roadways, automobile advertisers know that automobile drivers are likely to see their advertisements. Since drivers often listen to the radio while driving, automobile advertisers are likely to use this medium as well.
One medium that advertisers have not yet begun to utilize is the personal wireless communication device. Since the introduction of personal wireless communication devices, such as cell phones, the way in which people communicate with one another and access information has changed dramatically. Using conventional devices, subscribers stay connected on the road, in the air, and virtually anywhere a wireless network reaches. Wireless communication devices provide a variety of services ranging from phone calls, access to the Internet, and two-way text messaging. Utilizing these devices and services, wireless subscribers are able to carry out their day-to-day business from their cars, the jobsite, and even from different countries.
Due to advances in wireless technology, increases in coverage areas, and decreases in the costs of wireless services, the popularity of wireless services continues to grow. Along with a larger wireless market comes competition among equipment and service providers for customers. This competition has lead to better devices and more services, such as smaller phones, better displays, clearer reception, and text messaging.
Advertisers are constantly attempting to identify new forms and new mediums for advertising. And service providers are constantly searching for new and better revenue streams. In addition, consumers are constantly striving to increase the ease of access and the quality of information that they get from various information sources. What is needed is a way to combine wireless service providers' need to increase revenues, advertisers' need to present products and services to potential consumers, and a consumers' need for easier access to more information. By combining these, all parties will benefit. Revenues increase for service providers and advertisers, and consumers are able to make easier and more informed purchasing decisions. What are needed are methods and systems that work to achieve all of the above goals.

Systems and methods for a wireless messaging information service

BellSouth Intellectual Property Corporation


In a 2-piece solid golf ball comprising a solid core and a cover, the golf ball has a weight of 41-44.5 grams, the cover is formed of a thermoplastic resin having a Shore D hardness of 50-68 degrees, and the solid core has a surface hardness of 65-85 degrees and a center hardness of 60-80 degrees as measured by a JIS-C scale hardness meter, with the surface hardness.gtoreq. the center hardness+5. Despite a light weight, the golf ball is improved in flying distance and feel when hit at a relatively low head speed of 35-40 m/sec. The golf ball is thus appropriate for players of the beginner to middle rank.

1. Field of the Invention
This invention relates to a two-piece solid golf ball suitable for those golf players who swing at a relatively low head speed.
2. Prior Art
For golf balls, various proposals have been made for improving their flying distance and hitting feel. Most of these advanced golf balls are targeted to those golf players who swing at a relatively high head speed, that is, experienced players. These golf players are capable of high head speed swing and can take advantage of the advanced balls, enjoying an increased flying distance and a pleasant feel. However, those golf players who swing at a low speed and are slow in head speed, including beginner, female and senior players cannot take full advantages of the advanced balls including an increased flight distance and pleasant feel.
Usually, players with a slow head speed select softer types of the advanced balls. Since the softer balls, however, are not originally designed optimum for slow-head-speed players, the balls follow a low trajectory rather than a high trajectory and offer a less pleasant feel upon hitting.


There is provided a light source device, used in a display device and the like, having a high light emitting efficiency. The light source device has an electric discharge tube containing mercury and electrodes at both ends. A heat conducting member is attached to and is in contact with a part of the electric discharge tube. The heat conducting member locally cools the tube. The heat conducting member and the tube satisfy the following relationship, 6×10−5(m2·k)/S<(1/k1−1/k2)W, where a cross sectional area of the electric discharge tube is S (m2), an amount of generate heat per unit length of the electric discharge tubes is W (W/m), heat conductivity of the non-cooling part is k1 (W/K/m), and heat conductivity of the cooling part is defined as k2 (W/K/m).

1. Field of the Invention
The present invention relates to a light source device including an electric discharge tube that emits light by discharging electricity in a gas. In particular, the present invention relates to a light source device including an electric discharge tube comprising a cold-cathode tube using mercury as a discharge gas.
2. Description of the Related Art
A liquid crystal display device includes a backlight using an electric discharge tube comprising a cold-cathode tube, as a light source, for example. In the electric discharge tube, mercury is used as a light-emitting material. The mercury exists in the electric discharge tube in both liquid and gaseous states. The amount of the filled mercury is far (about 1,000 times) larger than the amount of vapor mercury that provides the maximum light emitting efficiency. In such an electric discharge tube, the maximum light emitting efficiency can be obtained when the electric discharge tube is at a predetermined temperature. However, if a large amount of electric power is supplied to the electric discharge tube, the temperature in the electric discharge tube rises so as to increase the mercury vapor pressure too much and to reduce the light emitting efficiency.
In Japanese Unexamined Patent Publication (Kokai) No. 2003-100130,that is the prior application of the present application, in order to prevent this phenomenon from reducing the efficiency, a technique has been proposed to provide a heat conducting path (a heat conducting material) that is in contact with the electric discharge tube so that heat is transferred from the electric discharge tube via the heat conducting path to cool the electric discharge tube. By providing such a heat conducting path, the liquid mercury is concentrated at the cooling part of the electric discharge tube that is in contact with the heat conducting path so that the mercury vapor pressure in the electric discharge tubes corresponds to the temperature of the cooled part of the electric discharge tube, which results in the maximum light emitting efficiency.
It is desirable that the liquid mercury is situated at the cooling part of the electric discharge tube that is in contact with the heat conducting path in a concentrated manner. However, the liquid mercury is distributed randomly in the tube before use and it concentrates at the cooling part gradually during use. Therefore, it is desirable to perform a procedure to concentrate or collect the liquid mercury at the cooling part in advance and before use.
In the prior art, there have been the following problems:
(a) if the process to concentrate the liquid mercury at specific positions is needed when the electric discharge tubes are manufactured, the cost may be increased;
(b) when droplets of the liquid mercury are displaced from the cooling part, due to impact, and the like, the light emitting efficiency may be reduced;
(c) conventionally, a heat conducting silicon rubber material (heat conductivity 1 to 2 W/K/m) or an aluminum plate is used as the heat conducting path. In both materials, the heat conductivity hardly depends on the temperature. Therefore, because the magnitude of temperature rise of the electric discharge tube, that is exposed to the ambient temperature, is always proportional to the heating value of the electric discharge tube, as the ambient temperature rises, the surface temperature of the electric discharge tubes varies proportionally and, as a result, the temperature inside the electric discharge tube cannot be maintained at an optimal value; and
(d) if the heat conducting path is large and dark in color, it may cast a shadow when it is incorporated as the backlight.

Light source device having high limit-emitting efficiency


A novel insulated cementitious building block is disclosed. This block has a substantially larger inside section or segment than the outside section or segment. Positioned between these two sections is a middle portion which houses the insulating material. The middle portion has a sinuous configuration thus holding more insulating material than a linear configuration. Griping holes which are compatible with conventional building blocks are provided which can act as conduits for electrical wires or the like. Also, these holes can later be filled with additional insulation to substantially enhance the insulating properties of the block.

There are known in the prior art several types of insulating cementitious building blocks such as those disclosed in U.S. Pat. Nos. 4,185,434; 4,551,959; 4,856,248; 4,986,049 and 5,066,440.
In U.S. Pat. No. 4,185,434 (Jones) the building block is formed from two block parts, one including the front wall of the block and one including the rear wall of the block. These two parts are maintained spaced apart by a layer of insulating material. There are internal "A" and smaller end cavities "B" in Jones' invention that are positioned so that when a plurality of blocks are placed in juxtaposition with each other to form a wall, the overall dimensions of adjacent cavities B are about the same as the dimensions of the cavities A. The cavities, corners and sections 4 and 5 all have squared or linear configurations which could cause the easy fracturing of the cementitious block when a strain is exerted thereon. Also, Jones' block does not have the appearance or feel of a conventional block and could present an unaccustomed structure for the mason to work with. In addition, main sections 4 and 5 are approximately the same size which could prevent obtaining maximum insulation properties as will later be explained.
In Schmid, U.S. Pat. No. 4,551,959, an insulating building block is described having two spaced supportive parts separated from one another by an insulating material. The block of Schmid is substantially solid with no griping holes or means for the mason or builder to work with when lifting and placing the block in position. In addition, the supportive parts 12 and 14 are substantially the same in size and configuration (column 3 lines 29-31). As above noted, maximum insulation properties are not provided when the inner or inside section of the block is the same size or smaller size than the outside section of the block. When the inside section has a larger mass or is of a greater size than the outside section, a significant improvement in insulating properties of the block can be realized. Also in Schmid, his projections 58 and 60 are smaller than the openings of the recesses surrounding these projections so that if the insulation 16 erodes away, sections 12 and 14 will easily separate and fall from each other.
In U.S. Pat. No. 4,856,248 (Larson) a building element or block is described having linear sections of varied densities. All sections of Larson are squared or have a linear configuration which could cause easy fracturing of portions of the block. Also, there are no grip holes in Larson's structure which would make it difficult for the mason to lift or place the blocks in position. Also, the sections of Larson identified by walls 80-82 and 90-92 are approximately the same size which does not provide maximum insulating properties of the block or building element.
In U.S. Pat. Nos. 4,986,049 and 5,066,440 (Kennedy et al) an improved building block is described having main sections 12 and 14 interlocked by T-shaped structures 34 and 36. Main sections 12 and 14 are approximately equal in size and do not provide any griping holes therein. Insulating portion 16 has thumb holes 154 which are intended to facilitate lifting of the blocks. Conventional cement masonry blocks have substantially large griping holes which workers are accustomed to using. Also, these conventional large griping holes, in addition to facilitating lifting, also provide convenient conduits for accommodating wiring and providing an opening or openings for re-bars that are used to reinforce walls. Therefore, the absence of griping holes and the equal mass of inside and outside sections 12 and 14 are important drawbacks to Kennedy et al's structure.
Also, as suggested in the prior art, breaking away a portion of a block to accommodate re-bar or to provide space for reinforcing rods is cumbersome and could cause block fracturing. Fracturing of the block obviously would compromise the integrity and strength of the wall.


Electrophoretic displays (EPDs) and methods for controlling EPDs are disclosed herein. An embodiment of an EPD includes a first operating format, wherein pixels on at least one area of the EPD are driven individually. The EPD has a second operating format, wherein a plurality of pixels constituting at least one area of the EPD are driven simultaneously. Both the first operating format and the second operating format are performable simultaneously on the EPD.

Some devices, such as electronic readers use electrophoretic displays (EPDs). The devices that use EPDs are sometimes referred to as electronic paper (e-paper) or electronic ink. EPDs may have very high resolution that may be comparable with liquid crystal displays. One of the unique properties of EPDs is that they reflect light rather than emit light; therefore, they simulate paper in that light reflects from the EPD. The EPDs are static in that individual pixels are turned dark or bright depending on the material being displaced to the display visible surface. For that reason, once a pixel is set, it will stay in that state indefinitely, even after power has been removed. Therefore, EPDs can display images for a long period using minimal or no power.
There are two formats for driving EPDs. A first format is wherein each pixel is controlled independently, which is sometimes referred to as the pixelar format. The pixelar format also allows for an EPD to change images very fast. However, the pixelar format requires a very high bandwidth and memory consumption to operate and may not be necessary for most applications.
The second format for driving EPDs is sometimes referred to as the regional format. In the regional format, groups of pixels are controlled or changed simultaneously. For example, the regional format may display a plurality of non-overlapping rectangles. A plurality of rectangles may form text that is displayed on the EPD. The regional format uses much less bandwidth and memory than the pixelar format because a lot of data stored to hold the display context is the same for all pixels. This format may provide high resolution, but it does not enable quick changes to images displayed on an EPD.

This patent is subject to a terminal disclaimer.

Operating an electrophoretic display with first and second operating formats


A wireless communication equipment includes a transmission destination information managing unit for managing transmission destination information specifying a respective actual transmission destinations when transmitting to other wireless communication equipments, and a transmitting/receiving unit for transmitting/receiving information for an associated application and information for managing switching between direct transmission and relayed transmission with other wireless communication equipments, to and from other wireless communication equipments based on the transmission destination information. Transmission destination information managing unit manages transmission destination information dynamically, in cooperation with the transmitting/receiving unit. The transmission destination information is updated to perform direct transmission and relayed transmission when direct transmission is possible and impossible, respectively. Each wireless communication equipment determines process to be performed in accordance with identification codes indicating transmission destination and transmission source of data, transmission destination and transmission source of a signal or a packet as well as other information, and relays the signal if necessary.

1. Field of the Invention
The present invention relates to a communication system for wireless data transmission/reception and to a wireless communication equipment used in such a system. More specifically, the present invention relates to a communication system and wireless communication equipments which allow automatic switching between direct transmission and relayed transmission in which data is transmitted from a transmission source equipment to a transmission destination equipment through a relay.
2. Description of the Background Art
Recently, much effort has been made to substitute wireless medium such as radio wave, infrared wave or ultrasonic wave for wired medium such as a coaxial cable or a twisted pair as the communication medium, in order to facilitate moving and layout of electronic equipments such as personal computers connected to LAN (Local Area Network). At present, wireless LAN products such as boards for personal computers have come to be commercially available.
Further, as portable terminals such as a so called electronic organizer have been improved to have wider variety of functions, portable terminals having communication function have been produced. At present, one to one communication is dominant in the field of wireless communication between portable terminals. However, N to N communication employing a wireless network including three or more portable terminals has been developed.
Data transmitted/received between the terminals are transmitted in the form of packets. FIG. 1 shows configuration of a packet 30 used in a conventional communication system. When wireless communication takes place between three or more communication equipments, the packet transmitted by the transmission source equipment is received not only by the transmission destination equipment but also by other communication equipments. Therefore, it is necessary to make clear from which communication equipment to which communication equipment the data is transmitted. For this purpose, packet 30 includes, in addition to the transmission data 38, an identification code 34 indicating transmission source equipment of the data, and an identification code 36 indicative of the transmission destination equipment of the data. Packet 30 further includes a packet type code 32 indicating the type of the packet, and other information 40. The communication equipment which has received the packet determines, depending on whether the data transmission destination identification code of the received packet matches the identification code of itself, whether the data is destined to it. The communication equipment which has received the data destined to it transmits a reception response packet to the transmission source equipment, so as to notify that the data has been received.
A conventional wireless communication system allows communication where direct communication between each of the equipment is possible. The conventional technique does not allow direct wireless communication between equipments between which wireless signals do not directly reach. In order to cope with this problem, the conventional wireless communication system further includes a wired network having a plurality of access points. In such a system, wireless communication is established between a terminal and an access point, and wired communication is established between each of the access points. Such a communication network presumes and is suitable for an environment in which terminals are stationary or terminals move only within a small range. Therefore, communication between terminals in the network is always possible after the operation of the network is confirmed when the terminals are set. Accordingly, arrangement of wire medium can be minimized.
However, there arises a new problem when terminals moving in a wide range such as portable terminals are to be used. More specifically, the portable terminal moves with the user, and hence the distance between the terminal and an access point vary widely. A condition where wireless communication between the terminal and the access point becomes impossible is more likely. Wireless direct communication between portable terminals without using a wire medium is possible. However, it is highly likely that the communication between portable terminals which has been successful so far suddenly becomes impossible if position of a terminal with respect to another terminal changes.
Routing technique used in the Internet has been known as a technique for establishing communication between terminals incapable of direct communication, through other equipments. However, the routing technique, which was originally developed for a wired network, cannot be applied as it is to a wireless network where state of connection with each terminal to the network may vary. Further, the routing technique requires its relaying equipment of high performance. Therefore, structures of the equipments constituting the network cannot be simplified.
The packet configuration shown in FIG. 1 may be utilized when relayed transmission is to be performed with a relay equipment determined in advance. However, as a relay equipment is fixed, the conventional packet configuration is not suitable for wireless communication network constituted by portable terminals in which condition allowing direct transmission tends to change considerably. When direct transmission from a transmission source equipment to a transmission destination equipment is not possible and relayed transmission through a relay equipment is desired, relayed transmission is not possible either, if direct transmission from the transmission source equipment to the relay equipment or direct transmission from the relay equipment to the transmission destination equipment is impossible.

Wireless communication equipment and communication system having automatic switching capability between relayed transmission/direct transmission


An exercise apparatus for performing a variety of exercises, including chest and incline shoulder press exercises during which the user sits on a seat with a backrest which is adjustably secured in upright and forwardly inclined positions for supporting the user's upper body in the proper positions for these exercises. The exercises all utilize the same weight stack or other device for resisting the exercise motions of the user. The apparatus has a plurality of exercise members mounted on a frame for different prescribed exercise movements by the user, a resisting force producing arrangement, and a cable for selectively connecting the resisting force to the different exercise members. The cable is guided and supported by pulleys, one of which is adjustable from one position to another to accommodate the different exercises.

1. Field of the Invention
This invention relates generally to exercise equipment and more particularly to a novel exercise apparatus for performing a variety of exercises all utilizing the same resisting force producing means for resisting the exercise movements of the user.
2. Prior Art
The ever increasing popularity of physical fitness has led to the development of a vast assortment of exercise devices. These devices range from the very simple, such as dumbbells, jump ropes, and the like, to relatively complicated and sophisticated exercise machines or apparatus designed for the performance of several different exercises. The present invention provides a novel exercise apparatus of this latter kind.
Exercise apparatus of the kind to which this invention pertains utilize various means to provide the required resisting forces for the various exercises which may be performed on the apparatus, that is the forces for resisting the exercise movements of the user. In some cases, these forces are developed by spring. In other cases, weights provide the required resisting forces. These weights are generally adjustable to vary the resisting force. Weights have the advantage over springs of providing relatively smooth and uniform resisting forces which remain essentially constant throughout the range of movement of the exercise members.


The invention relates to a carrier system having a front part and a back part and means for fastening to a human torso. The carrier system also has a hip belt which can be connected to the back part via at least one support. It is provided that at least a part of the means for fastening to a human torso has first fastening means and the back part has second fastening means, the first and the second fastening means together forming a fastening device with fastening loops and receptacles. The receptacles are provided with slots. The fastening loops can be inserted into or passed through the receptacles. Furthermore, an elongated fixing element is provided which can be passed through those ends of the fastening loops which have been inserted into the receptacles.

1. Field of the Invention
The invention relates to a carrier system having a front part and a back part and means for fastening to a human torso, according to the preamble of Claim 1.
2. Description of the Related Art
From the general prior art, carrier systems are known which have a front part and a back part and which are generally of ballistic design and referred to as ballistic protective vests or armoured or projectile-stopping protective vests. Ballistic protective vests for wearing on the body are usually used by military and police forces to protect persons against attacks involving stabbing weapons or projectiles.
To ensure ballistic protection, the protective vests for wearing on the body generally have a projectile-inhibiting composite composed of a plurality of layers. Here, a distinction, is made substantially between so-called soft ballistic and hard ballistic protective packages.
The known ballistic protective vests generally have a front part and a back part which are intended to offer protection against stabbing weapons and/or against firearms.
A generic carrier system is known from EP 2 052 632 A1. Here, the carrier system is composed substantially of three components, specifically firstly a ballistic protective vest having a front part and a back part and means for fastening to a human torso. Secondly, the carrier system has a hip belt which can be arranged around the hips of a person, and thirdly, the carrier system has two lateral supports which connect the hip belt to the rear shield-shaped region of the ballistic protective vest, that is to say the back part thereof. Electronic components, for example a radio unit, may be integrated in the back part of the ballistic protective vest.
The hip belt known from the generic document with the lateral supports facilitates the wearing of a protective vest without excessively restricting the freedom of movement of the wearer. Furthermore, the lateral support may if required be designed so as to convert a relative movement, which a person generates between the hip and torso while walking, into an electrical current. For this purpose, reference is made also to EP 1 994 841 B1, which claims such a design.
The protective vest known from EP 2 052 632 A1 in combination with the hip belt has proven to be particularly suitable for military and police uses and applications.
In the case of the described carrier systems, it is particularly essential that these can be quickly abandoned or discarded in an emergency.

Carrier system having a front and back part and means for fastening to a human torso


Hydrodynamic baits for the control of orthopterous insects are disclosed which contain an attractant, a humectant and a gel former. The baits are designed to function in harsh and/or dynamic microclimates such as for example commercial kitchens or outdoor environments subject to typical circadian influences such as temperature and moisture. A further advantage of the disclosed baits is their lack of attractiveness to mammals.

1. Field of the Invention
This invention relates to a system for the control of insects, especially cockroaches, that includes hydrodynamic baits, that can be flowable or formable, and to a method for controlling insects, especially cockroaches, using the hydrodynamic baits.
2. Description of the Related Art
Cockroaches are primarily tropical insects but some species have become widely disseminated through commercial activities and are now cosmopolitan. The domestic species are omnivorous but are especially attracted to starchy or sweetened matter of various kinds; they also attack food, paper, clothing, books, shoes, bones, and dead insects. They are the orthopterous insects that are involved in the contamination of food. Of the many species of cockroaches, house inhabitors include American (Periplaneta americana), oriental (Blatta orientalis), Australian (P. australasiae), German (Blattella germanica), brownbanded (Supella longipalpa (F.)), smokybrown (P. fuliginosa (Serville)), and Florida woods (Eurycotis floridana (Walker)) cockroaches. They prefer secluded, warm, damp places and at night or on dark days, they sample filth and foods and impart to infested areas an unpleasant odor.
A number of food attractants have been formulated with toxicants and aqueous gel binders to provide toxic paste baits for cockroaches. For example, Doi et al. (Chem. Abst. 107:12915n(1987)) controlled cockroaches with a paste containing boric acid, potato strach, corn strach, rice bran, molasses, water, and dye; Barson (Chem. Abst. 97:87017k(1982)) used a mixture of boric acid plus porridge oats and iodofenphos gel; Peeters (Chem. Abst. 84:131508d (1976)) combined bakery wastes, boric acid, and water. Similarly, the proprietary roach bait station sold under the trademark, "It Works" (Bridgeport, Conn.) is advertised as containing boric acid, an attractant, and a humectant.
One of the key necessities for arthropod survival is moisture. When temperatures increase, the metabolism of cockroaches and other insects increase. Subsequently, they have an increased need for food and will find a bait that is also a good moisture source. Silverman (Australian Document No. AU-B-73766/87) discloses a bait that incorporates water as an attractant to lure cockroaches to a poisoned bait. The bait is a solid, non-particulate, non-flowable, non-repellent, fully edible insecticide-bait composition with a pentadienone hydrazone insecticide compound, a specific food attractant system and a binder. The water attractant can be in a container close to the bait or in a cup-like container built into the feeding station containing the bait. The water can also be formulated into the bait using a water absorbent material such as a water absorbing polymer, especially an electrolyte polymer that does not contain natural polymer such as starch and contains synthetic carboxylate and hydroxyl groups, has a high water-absorption ratio and has excellent water-retaining properties as well as good strength after absorbing water. The particular polymers are a saponified copolymer of vinyl ester (x) and ethylenic unsaturated carboxylic acid or its derivative (y) sold under the name SUMIKAGEL.RTM. S-50 and the polyvinyl alcohol-acrylate graft polymer.
Ong (U.S. Pat. No. 4,812,309) discloses a gel composition for the control of cockroaches that includes a gellant, propyl p-hydroxybenzoate, propylene glycol, fatty acids, an insecticide, high fructose corn syrup, isopropyl alcohol, methyl p-hydroxybenzoate and water where the gellant is a non-ionic surfactant. The composition can be distributed so that it poses little or no hazard to humans or animals that may frequent the infested area.
Brenner et al (U.S. Pat. No. 4,988,510, herein incorporated by reference) disclose a hydrophilic gel bait which is deformable (non-flowable) that includes corn distiller's grains with solubles as an attractant for cockroaches. This bait includes a humectant, insecticide, a gel former, and optionally a preservative. This bait provides both food and a relatively moist environment for cockroaches.
Dried mash from a distillery was reported by Adler (J. Environ. Sci. Hlth., A20:839-844(1985)) to be specifically attractive for the brownbanded cockroach, Supella longipalpa (F.), but it failed to attract American cockroaches, Periplaneta americana (L.). In contrast, Brenner et al (Ann. Entomol. Soc. Am. 81:581-592 (1988); J. Econ. Entomol. 82:159-162(1989)) reported that distiller's dried grains with solubles (DDGS, Agricultural Energy Corp., Franklin, Ky.) was attractive to 15 species of cockroaches including American cockroaches. Furthermore, the DDGS is advantageously unattractive to nontarget mammals, in contrast to other baits such as pieces of fruit, bread, and beer (Jackson et al., Am. J. Trop. Med. Hyg. 4:141-146 (1955); Ohio J. Sci., 61:220-226 (1961); Reierson et al., Pest Control 45:40, 42-44 (1977); Fleet et al., Environ. Entomol. 14:669-673(1985) or dry cat food (Appel et al., Environ. Entomol. 14669-673(1985)) which are attractive to mammals as well as cockroaches.
Bruey (U.S. Pat. No. 5,021,237) discloses a gel insecticide bait that is dispensed from a pressurized container which is made up of a pentadienone hydrazone as a toxicant, a fatty acid, a lower alcohol, a sugar, a gellant, water, a base and a hydrocarbon propellant. The gel bait composition is an oil-in-water emulsion of a toxicant-fatty acid mixture in a corn syrup solution. It is sufficiently fluent to be dispensed from a pressurized package and the deposited form will retain sufficient bulk to be ingested by cockroaches over a long period of time.
While various gel baits have been developed for the control of insects, especially cockroaches, there still remains a need in the art for a more effective bait form that provides food and moisture, especially when insects are most in need of food and moisture. The present invention provides hydrodynamic insect baits which function well in harsh microclimates and are different from the prior art baits and solves some of the problems associated with prior art baits.

Method for controlling a target insect and hydrodynamic insect bait

The United States of America, as represented by the Secretary of Agriculture


Described is a method wherein a computer terminal is coupled to a power supply through a docking arrangement. The docking arrangement includes a protection circuit. A current supplied to the computing terminal is detected. When the current is greater than a predetermined value, the computer terminal is decoupled from the power supply. After the computer terminal is decoupled from the power supply, the computer terminal is recoupled to the power supply, and the method repeats beginning with detecting the current supplied to the computing terminal.

In a conventional computing network, a plurality of components may be coupled to a common device for power management and/or data transfer. For example, the common device may be a cradle which receives one or more mobile computing terminals. Upon connection to the cradle, the terminal may receive power therefrom (e.g., charge a battery) and communicate with a network device (e.g., a server) coupled thereto. However, upon connection or during operation, one or more of the terminals may experience a short circuit causing the remaining terminals and/or the cradle to malfunction. The short circuit results in delivery of an excessive amount of power to the shorted terminal, inhibiting operation of the remaining terminals. Also, the excessive amount of energy may generate a great deal of heat, potentially resulting in a fire or an explosion.
A conventional method of protecting against the short circuit involves terminating power delivery to each of the terminals once the short circuit is detected. For example, when a terminal short circuits, the cradle will terminate power delivery to all of the terminals connected thereto. This may interrupt operation (e.g., data transfer, charging) of the terminals which did not short circuit. A user must manually reset the cradle and correct the short circuit to reestablish power delivery to the terminals. Thus, there is a need for a system which may experience the short circuit without interrupting operation of the terminals and does not require user intervention.

System and method for power delivery to computing terminals


The present invention relates to blocked polyisocyanates based on the reaction product of. i) an organic polyisocyanate comprising a member selected from the group consisting of bis-(4-isocyanatocyclohexyl)-methane, NCO prepolymers prepared from bis-(4-isocyanatocyclohexyl)-methane, polyisocyanate adducts prepared from bis-(4-isocyanatocyclohexyl)-methane, isocyanurate group-containing polyisocyanates prepared from 1,6-hexamethylene diisocyanate and isocyanurate and allophanate group-containing polyisocyanates prepared from 1,6-hexamethylene diisocyanate with PA0 ii) methylamyl ketoxime.

1. Field of the Invention
The present invention relates to methylamylketoxime (MAKO) blocked polyisocyanates, which have a significantly reduced viscosity when compared to corresponding polyisocyanates blocked with methylethylketoxime (MEKO), and to the use of these polyisocyanates in high solids coating compositions.
2. Description of the Prior Art
In view of the increasing number of regulations requiring a reduction in the amount of volatile organic solvents present in coating compositions, many attempts have been made to formulate high solids coating compositions. One possibility is to optimize the selection of solvents or blends of solvents to determine those which provide the greatest reduction in viscosity based on the weight of the solvent. Another possibility is to formulate the coating compositions with lower viscosity raw materials.
Coating compositions based on a blocked polyisocyanate component and a polyol component are known. The purpose of the blocking agent prevents the polyisocyanate component from reacting with the polyol component prematurely. An advantage of these coating compositions over those based on fully reacted polyurethanes is that the viscosity of the individual components is less than the viscosity of the fully reacted polyurethane. During subsequent curing of the coating composition at elevated temperatures the blocking agent is released and the polyisocyanate and polyol components react to form a high molecular weight polyurethane.
One of the preferred classes of blocking agents are the oximes. These blocking agents provide the good storage stability which is generally associated with caprolactam blocking agents, yet release the blocking agent at much lower temperatures than those needed for caprolactam blocking agents. By good storage stability it is meant that the blocking agents prevent a premature reaction from occurring between isocyanate groups and hydroxyl groups which would increase the viscosity and possibly gel the coating composition.
Even though coating compositions based on oxime-blocked polyisocyanates and a polyol component have a lower viscosity than fully reacted polyurethanes, it is an object of the present invention to further reduce the viscosity of these systems without affecting the properties of the coatings obtained therefrom.
These objectives may be achieved in accordance with the present invention by using methylamyl ketoxime (MAKO) as the blocking agent for the polyisocyanate component. Certain polyisocyanates blocked with MAKO possess lower viscosities when compared to the same polyisocyanates blocked with methylethyl ketoxime (MEKO).
U.S. Pat. Nos. 4,486,556 and 4,708,995 are representative of a series of patents relating to electrodeposition coatings. Both of these patents describe the preparation of blocked polyisocyanates by blocking a biuret group-containing polyisocyanate based on 1,6-hexamethylene diisocyanate and an isocyanurate group-containing polyisocyanate based on toluene diisocyanate with MAKO. U.S. Pat. No. 4,847,346 describes the preparation of an MAKO-blocked polyisocyanate adduct wherein the adduct is prepared by reacting toluene diisocyanate with trimethylol propane. U.S. Pat. No. 4,808,658 describes the preparation of a polyisocyanate adduct blocked with 2-octanone oxime wherein the adduct is prepared by reacting isophorone diisocyanate with trimethylol propane. U.S. Pat. No. 4,794,154 describes the preparation of an MAKO-blocked polyisocyanate adduct wherein the adduct is prepared by reacting .alpha., .alpha., .alpha.',.alpha.'-tetramethyl-xylylene diisocyanate with trimethylol propane.
U.S. Pat. No. 4,596,744 is directed to the use of oximes containing at least 7 carbon atoms, preferably MAKO, as blocking agents. The preferred polyisocyanates are adducts prepared by reacting toluene diisocyanate with trimethylol propane and isocyanurate group-containing polyisocyanates based on 1,6-hexamethylene diisocyanate. However, in view of the fact that neither of these polyisocyanate adducts was blocked with MAKO in the examples of this reference, there is no recognition of the improvement in viscosity which may be obtained when the specific polyisocyanates of the present invention are blocked with MAKO.

Methylamylketoxime blocked polyisocyanates and their use in high solids coatings compositions


A method, system, apparatus, and/or device for capturing an image from an aerial vehicle. The method, system, apparatus, and/or device may include a boom, a motor, a propeller, a controller, a top plate, a bottom plate, and an image capturing device. The boom may be an arm that extends outwardly. The motor may be connected to an end of the boom. The propeller may be connected to the motor. The motor may be configured to rotate the propeller to lift the system, the apparatus, and/or the device into flight when the motor is engaged. The controller may be configured to control the motor. The top plate may be connected to a first end of the boom. The bottom plate may be connected to a second end of the boom. The image capturing device may be mounted to the top plate or the bottom plate.

Aerial vehicles such as unmanned aerial vehicles (UAVs) can be used for performing surveillance, reconnaissance, and exploration tasks for military and civilian applications. The aerial vehicles may carry a payload configured to perform a specific function. For example, the aerial vehicles may include sensors to capture images of the environment surrounding the aerial vehicles. In some instances, it may be desirable to obtain panoramic images using the aerial vehicles.


Rollers having a cylindrical configuration without substantial end relief are positioned between and exert a force against an outer raceway contact area and a cylindrical inner raceway contact area. The outer raceway has a crowned configuration such that a calculated maximum contact stress over the outer raceway contact area is controlled with respect to the maximum contact stress over the inner raceway contact area in order to make the outer raceway life substantially equal to the inner raceway life.

This invention relates generally to roller bearings and, more particularly, to a roller bearing with modified geometry to control contact stress and extend bearing life.
In conventional roller bearings, the rollers typically have relieved ends to allow for misalignment or slope of the outer ring with respect to the shaft. The relieved ends adequately accommodate the misalignment without excessive end loading, but the end relief on the rollers shortens their contact length and raises the contact stress on the outer ring and shaft. Contact stress is higher on the shaft than on the outer race because the contact area is narrower on the shaft than the contact area on the outer race. As a result of this higher contact stress, fatigue failure of the shaft is the principal mode of failure of such bearings.
The foregoing illustrates limitations known to exist in present devices and methods. Thus, it is apparent that it would be advantageous to provide an alternative directed to overcoming one or more of the limitations set forth above. Accordingly, a suitable alternative is provided including features more fully disclosed hereinafter.

Controlled contact stress roller bearing


The present invention is an integrated bill consolidation, payment aggregation, and account-payment application system. The system acts as a settlements exchange for the execution of payments between households or small businesses and the service establishments (principally utilities, financial institutions, telecoms, and others) that serve them. The system eliminates paper check payments without requiring automation at the household level (for example, telephone bill-pay, PC payment systems). The invention provides for the consolidated billing of a plurality of services to a plurality of households, the payment to individual service establishments in aggregate "bullet" transfers (verses individual household payments), and the automated application of payments to service establishment accounts. The present system computes, stores, and communicates the information needed to direct the financial institution processing of debit and credit transactions between thousands of service establishments providing goods and services and millions of consuming households. The system provides for a number of methods of payment, adjusts for partial and delayed payments, and automatically structures and schedules payments in arrears.

Conventional household bill payment is based on the receipt by mail of a paper statement from each service establishment for each billing period.
Households issue a multitude of paper checks and associated paper return stubs to these service establishments and the payments are cleared through banks, credited to service establishment bank accounts, and applied or credited to the household accounts on record. In this conventional system, for example, a city of 3 million households, each writing only 5 checks each month will generate more than 60 million paper transactions per month, or 720 million in a year.
Conventional payment systems are designed to handle these inefficient paper payments on a large scale, causing more efficient alternatives to actually increase costs, because they require special "exception" handling. Nevertheless, there has been substantial focus on electronic alternatives to paper checks and stubs. Typically, these electronic alternatives involve automating the consumer interface to enable the creation of electronic transactions, such as, for example, telephone bill-paying, service bureaus, automatic teller machine payment, internet-based home banking, and electronic bill presentment and payment. However, households do not easily adopt new payment systems on a large scale, and receiving service establishments generally resist the associated exception costs. While Internet-based electronic bill presentment and payment may eventually come into widespread use, to date, commercially viable alternate payment technologies have had a negligible impact on reducing the inefficiencies inherent in conventional paper-based bill payment.
Thus, what is needed is an automated household bill payment system that eliminates paper-based bill payment. The system should be easily adaptable to household use on a large scale. The system further should be low cost to service establishments. The system further should not require electronics or automation at the household point of payment. The system should readily accommodate and directly facilitate the eventual transition to full electronic bill presentment and payment over electronic networks.

Integrated bill consolidation, payment aggregation, and settlement system


Methods and apparatus for redrawing a drawn cup are disclosed. In particular, the methods and apparatus disclosed are directed to redrawing a container body for use in a two piece beverage container. The redraw operation uses a redraw sleeve and a redraw ring that prevent wrinkles when a thin gauge metal is employed. The wrinkles are prevented by providing cooperating displacements on the surfaces of the redraw ring and the redraw sleeve that clamp the bottom surface of the cup that is being redrawn. This displacement provides a convoluted path through which the metal is pulled during the redraw operation to increase the resistance to being drawn and the tension in the side wall, thereby substantially eliminating wrinkles.

The drawn and ironed two piece beverage container is a highly engineered article of manufacture. However, improvements are constantly being sought that will permit reliable containers to be made with less metal. Due to the extremely high volume in which such containers are manufactured, even the smallest savings in the metal from which they are made can result in enormous cost reductions. For example, it would be desirable to reduce the starting gauge of such containers by as little as one one-tenthousandth (0.0001) of an inch.
One of the fundamental operations required to form a two piece beverage container is the drawing, redrawing and wall ironing of a thin sheet of metal into a deep cup that essentially forms the body of the container, i.e., the portion that holds the liquid. Although the bulk of the drawn and ironed containers presently manufactured are formed of aluminum or aluminum alloys, other metals, such as steel are also drawn and redrawn using substantially the same techniques.
U.S. Pat. No. 4,425,778--Franek et al. discloses methods and apparatus for redrawing a can body by pulling the side wall through an S-shaped path by bending the side wall of the cup that is being redrawn around a redraw ring to induce tensions to stretch the metal and reduce the wall thickness that can be redrawn without wrinkles.
U.S. Pat. No. 4,685,322--Clowes discloses a redrawing die that has an inwardly projecting annular bead formed on the redraw ring to prevent wrinkling in the end wall of a container as it is redrawn.
U.S. Pat. No. 4,962,659--Inazu et al. discloses apparatus for redrawing a drawn cup by relatively moving a redrawing die in a redrawing punch wherein the redrawing die and punch comprise portions that engage one another to clamp the cup and permit a redrawn cup of a relatively thin wall to be reformed.
U.S. Pat. No. 5,083,449--Kobayashi et al. discloses apparatus for redrawing a flanged cup using a redraw ring that has a working face having an inner diameter which is gradually decreased and a peripheral portion that clamps the flanged cup to the redraw ring.
However, it has been found that using the methods and apparatus of the prior art, as the gauge of the metal is reduced, wrinkling occurs in the unsupported nose portion of the container as the cup is redrawn. For this reason, a wrinkle-free redrawn cup cannot be produced when the thickness of the base metal is below 0.0113 inches using the technology currently available. Radial faults develop in the area of the cup face that is not directly clamped nor in contact with the punch. This phenomenon is thought to be due to insufficient holding force being developed between the bottom of the cup, the face of the redraw ring, and the corresponding face of any clamping means associated with it. It would be desirable to provide methods and apparatus whereby thinner gauge metals could be redrawn to produce lightweight container bodies. Therefore, it is an object of the present invention to provide methods and apparatus for increasing the clamping force during a redraw operation such that the wrinkling of the unsupported nose portion is eliminated.

Methods and apparatus for redrawing thin-walled container bodies


A method and an apparatus for making a simple sugar solution from a liquid solution including at least one compound sugar by performing hydrolysis in the presence of a heterogeneous catalyst. The method comprises contacting the hydrolysis reaction medium with at least one microporous solid adsorbent compound selected for compatibility with the hydrolysis and . catalysis conditions and for selectively adsorbing by-products other than simple sugars under the hydrolysis reaction conditions. A pure, colourless, food-grade simple sugar solution is achieved.

The reaction of the hydrolysis of compound sugars in liquid medium, generally an aqueous medium, in the presence of an acidic catalyst, is known. This reaction, sometimes known as "sugar inversion reaction" makes it possible normally to obtain an "invert sugar", that is to say a mixture of simple sugars, in particular of hexoses. In particular, if one starts from a solution of saccharose, one obtains an invert sugar formed of a mixture of fructose and glucose.
The article "Les sucres invertis" (Invert sugars) by BUSSIERE et al. in the IAA, July/August 1990, pages 645 to 649, already describes the hydrolysis reaction in the presence of ion exchange resins as heterogenous acidic catalysts. In order to avoid the formation of coloring substances, it has been believed up to now that it is preferable to operate at low temperature (on the order of 30.degree. to 35.degree. C.). In particular, in the case of the hexoses, it is convenient to avoid the formation of hydroxymethylfurfural (HMF) and of its derivatives or intermediates (polymers, humins, levulinic or formic acid, etc). Now, the actions resulting in the formation of HMF and its derivatives are also catalyzed in acid medium and favored by an elevated temperature, in particular, a temperature above 50.degree. C. Furthermore, the use of an ion-exchange resin as acidic catalyst prohibits high temperatures.
It is to be noted in this connection that if it is desired actually to obtain a mixture of simple sugars, it is advisable to see to it that the reaction stops at the hydrolysis stage, without going beyond it to the degradation of the sugars and the formation of derivative products such as polyols, polymers, acids, HMF, or the like.
Up to now, it has therefore been preferred to limit the conversion rate of the compound sugar in order to avoid the formation of undesirable by-products. Thus, the known hydrolysis reactions do not make it possible, under economically profitable conditions, to obtain pure solutions of fully converted simple catalysts, that is to say without compound sugar or derivative products.
Furthermore, at the low temperatures used up to now with the ion-exchange resins, the conversion of the compound sugar is slight and the reaction requires considerable time, conventionally on the order of 12 to 48 hours.
Furthermore, the compound sugars have a high viscosity at these temperatures. It is now possible in actual use to employ a starting solution which is strongly concentrated in compound sugar, and a concentration step must be provided after the hydrolysis.
Similarly, the use of ion-exchange resins results in numerous drawbacks from an industrial standpoint, such as the formation of waste, difficulties in regeneration, and a high cost of production.
Thus, FR-A-1526 029 describes a process of decolorizing juice, syrup, molasses and even sugar mill waste permitting transforming totally or in part the saccharose comprising a step of decolorizing by ion exchange resins, with partial or total hydrolysis, a step of purification and decoloration by ion exchange resins and a step of concentration. The starting products being highly loaded with cations and anions, the resins are rapidly saturated, so that the process cannot find practical application in industry. Moreover, this process is in several steps, and requires a low inlet concentration (20 to 30 Brix).
For all of these reasons, the known processes, such as the one described in the aforementioned article, have known only limited industrial development and do not make it possible to produce invert sugars at low cost.

Method and apparatus for making a pure simple sugar solution by hydrolyzing at least one compound sugar in the presence of a selective adsorbent


A reflection-type liquid crystal displaying device includes an optically transmitting first substrate on which an optically transmitting electrode is at least formed; an anisotropic scattering/reflecting plate for performing a function of anisotropically scattering an incident light and a function of reflecting a light; and a liquid crystal layer disposed between the optically transmitting first substrate and the anisotropic scattering/reflecting plate. The obtained reflection-type liquid crystal displaying device exhibits an extremely bright, uniform, and good displaying capability.

1. Field of the Invention
The present invention relates to a reflection-type liquid crystal displaying device that can be applied to various displaying apparatuses
2. Description of the Related Arts
Liquid crystal displaying devices consume less electric power than TV cathode-ray tubes since liquid crystal displaying devices employ a non-light-emitting method in which external light is modulated. Also liquid crystal displaying devices exhibit an excellent property that they are thin and light, suitable for application to flat panel displaying apparatuses. Therefore, by utilizing these features, liquid crystal displaying devices are now used for displaying apparatuses such as watches, electronic calculators, computer terminals, notebook-type computers, and word processors. Further, liquid crystal displaying devices are now used for displaying in television receivers instead of cathode ray tubes and, at present, they are used for various application fields.
A well-known representative display mode for modulating the light intensity by utilizing liquid crystals in a liquid crystal displaying device is what is called a TN (Twisted Nematic) mode in which the orientation of the liquid crystal molecules in a liquid crystal cell is twisted by about 90.degree. as initial orientation. In the TN mode, liquid crystal cells are disposed between a pair of polarizing plates, and black-and-white display is realized by utilizing the optical properties of the liquid crystal cells (namely, the rotatory power exhibited when no voltage is applied and dissolved when a voltage is applied).
In liquid crystal displaying devices of a simple matrix driving type, an STN (Super Twisted Nematic) mode is widely adopted. The STN mode utilize a cell structure which is similar to that of the TN mode and in which the twisted angle of the liquid crystal molecules are set to be within the range from 180.degree. to 270.degree.. In the STN mode, a sharp change in the orientation state of the liquid crystal molecules in accordance with the increase in applied voltage is reflected to change in birefringence (double refraction) of the liquid crystal by setting the twisted angle of the liquid crystal to be more than 90.degree. and further optimizing the set angle of the polarizing direction of the polarizing plates, thereby realizing an electro-optical property having a sharp threshold value. Accordingly, the STN mode can provide an electro-optical property having a sharp threshold voltage and, hence, is suitable for liquid crystal displaying devices of a matrix driving type. However, the STN mode has a disadvantage that the background of the display turns yellowish green or dark navy-blue due to birefringence of the liquid crystal. For reducing the above disadvantage, a liquid crystal displaying device has been developed in which black-and-white display is provided by color correction. The color correction is performed by superposing an optical compensating panel or a phase difference plate formed of a polymer such as polycarbonate on the STN liquid crystal display panel.
In a liquid crystal color displaying device having such a structure, multi-color display or full-color display is realized by additive color mixture by providing, for example, three-dot (red, green, and blue) micro color filters of minute dimension for each display pixel within a liquid crystal cell. However, these display modes have a disadvantage that the view angle is narrow due to the use of a polarizing plate and also, in principle, the display will be extremely dark because half of the incident light is not utilized for the display. Therefore, these display modes could not be applied to reflection-type liquid crystal displaying devices.
Accordingly, for use which requires brightness, a reflection-type liquid crystal display mode that is supposed to have a good prospect is what is called a guest-host mode in which a pigment (a dichroic pigment) having two different light absorptivities with respect to longitudinal and lateral directions of the pigment molecule is added to liquid crystals without using a polarizing plate. These guest-host modes may be classified into a Heilmeier type which uses a polarizing plate (See G. H. Heilmeier et al. Appl. Phys. Lett., 13, pp. 91, 1968), a White/Taylor type which does not use a polarizing plate (phase transition type: See D. L. White et al. Appl. Phys. Lett., 25,683, 1974), a two-layer type (See T. Uchida, Proc. SID, 22, pp. 41, 1981), and others. The principle of operation in these types of display modes is the same. Namely, the principle of operation in the guest-host mode is that the orientation of a pigment molecule is controlled via the orientation of the liquid crystal molecules by applying a voltage so that the difference in light absorptivity with respect to the direction of the pigment molecule may be reflected to the display.
Another method for providing a color display in the guest-host mode involves utilizing a pigment which absorbs visible light of a certain wavelength. In addition to this, there is proposed in Tohru Koizumi et al. Proceedings of the SID Vol. 29/2, pp. 157, 1988 a reflection-type liquid crystal color displaying device in which guest-host cells utilizing a black pigment are combined with a micro color filter. This article discloses a method of manufacturing a reflecting plate for a reflection-type liquid crystal color displaying device, the reflecting plate having an optimal reflection property by a control of the irregularity (unevenness) of the reflecting surface. This method employs subjecting a glass substrate to surface roughening treatment with a polishing agent, varying the time for etching the substrate with hydrofluoric acid so as to control the irregularity of the substrate surface, and forming a thin Ag film on the irregular surface to complete the reflecting plate.
However, in the above method of fabricating a reflecting plate for a reflection-type liquid crystal color displaying device, the glass substrate surface is damaged by a polishing agent for forming the irregular portion, so that it is not possible to form an irregular portion having a uniform shape with good reproducibility. Therefore, it is extremely difficult to provide a uniform reflection property with good reproducibility by such a reflection-type liquid crystal displaying device obtained by using a reflecting plate fabricated to have an ununiform irregularity formed on the glass substrate.

Reflection--type liquid crystal displaying device


Aspects of the invention provide an error amplifier that can compare a feedback voltage of an output voltage with a reference voltage to produce a resulting error signal in cooperation with a phase compensating circuit. In some aspects of the invention, an AC detecting circuit makes a decision as to whether a detected input voltage signal is that of a 100 Vac system or that of a 200 Vac system to change the gain of the error amplifier according to the result of the decision. When the voltage signal Vis is lower than the threshold voltage established beforehand, for making the transient response speed of the phase compensating circuit faster, the AC detecting circuit increases the gain of the error amplifier. When the voltage signal is higher than the threshold voltage established beforehand, for making a power factor higher, the AC detecting circuit decreases the gain of the error amplifier.

1. Field of the Invention
Embodiments of the invention relate to control circuits and improved power factor power supply systems.
2. Related Art
A switching converter (switching power supply system) having an output of an AC (Alternating Current) power supply as an input makes switching devices connecting the input and the output carry out switching operations to thereby invert a full wave rectified AC input voltage to a DC output voltage at a desired level to supply the DC output voltage to a load. Such a switching converter is widely used in devices such as electronic devices.
In such a switching converter, for ensuring stabilization and safety of a commercial electric power system, a power factor improvement is required for switching converters with power consumption thereof exceeding 75 W, for example. By the power factor improvement, loads on facilities in distribution systems are reduced to permit reduction in electric power costs.
In an improved power factor switching converter, when a load is inductive, the phase of an input current delays to the phase of an input voltage. Thus, by carrying out an adjustment for making the input current become in phase with the input voltage, the power factor is made enhanced. The converter is also provided with an error amplifier comparing an output voltage with a reference voltage and a phase compensation circuit for compensating the phase of an error signal as a result of the comparison in the error amplifier.
For obtaining a high power factor, the value of the gain of the error amplifier and the value of the phase compensation constant (time constant) of the phase compensation circuit are to be established to adequate values. This, however, caused a slow transient response when an input voltage became particularly low in a circuit with the phase compensation circuit being additionally provided to sometimes lower the response of the circuit.
For improving the delay in the transient response, a technique is proposed with which an output voltage is detected and, when the overshoot or undershoot in the detected voltage accompanied with the transient response becomes large, the gain of an error amplifier is made promptly increased. See Japanese Patent Application No. P-A-2011-211828 (also referred to herein as "Patent Document 1").
With such technique as is proposed in Japanese Patent Application No. JP-A-2011-211828, however, when the input voltage is high, the power supply gain also becomes high. Hence, there was a problem in that the further prompt increase in the gain in the error amplifier with the input voltage being high might cause the oscillation in the output voltage. Moreover, when the input voltage is low, there was also a problem with respect to the undershoot of the output voltage in that an adequate value of a phase compensation constant was difficult to be established to make the circuit design difficult.
Thus, as described above, certain shortcomings exist in the related art.


Disclosed is a mayonnaise base which is mixed with eggs by consumers to give mayonnaise. The mayonnaise base consists indispensably of vegetable oil, vinegar and emulsifier (except egg yolk) along with other seasonings (except vinegar) and spices, and is stored in an oxygen-free container. The mayonnaise base is mixed with fresh eggs by consumers to give mayonnaise with ease. In accordance with the consumers' request, either whole eggs or only egg yolk or albumen can be added to the mayonnaise base.

The present invention relates to a novel mayonnaise base and a method for producing it.
The flowchart of FIG. 1 shows one typical example of the conventional production of mayonnaise, which is as follows:
Vinegar (suitably diluted with water) and egg yolk (emulsifier) are, while being stirred, mixed with seasonings and spices (these are generally soluble in water), to which is added vegetable oil (salad oil) and further stirred to give an oil/water (o/w) emulsion.
However, this method is complicated, as comprising many steps.
In addition, in this method, since egg yolk is used as the emulsifier, the worsening of the flavor of the product, mayonnaise is inevitable due to the deterioration of the egg yolk, even though the product, mayonnaise is stored in a sealed container.
In order to solve the latter problem, homemade mayonnaise is the most desirable. However, homemaking of mayonnaise is also complicated like its industrial-scale production as above.
Accordingly, for example, a mayonnaise base has been proposed in Japanese Patent Application Laid-Open No. 48-36373. Using the mayonnaise base, one can produce homemade mayonnaise with ease.
The mayonnaise base is produced by mixing 4 g of mustard paste in 4 g of water with 1 g of vinegar, 1.4 g of white oil extract, 2.4 g of edible salt, 6.6 g of sugar and 0.6 g of glutamic acid in that order with stirring, and it contains spices and seasonings which are additives to mayonnaise.
Using the mayonnaise base, mayonnaise is produced as follows:
The mayonnaise base is put into a cylindrical container, to which are added one egg yolk and 15 cc of vinegar. These are stirred in the vertical direction to give a fine-grained mixture, which is further stirred in the vertical direction with dripping thereto 90 cc of salad oil through the space between the bottom hole of the concave cap and the stirring rod to give a creamy paste. Then, 7.5 cc of vinegar is added to the paste, and further stirred in the same manner as above with dripping thereto 90 cc of salad oil. Thus is obtained mayonnaise.
However, though not requiring the addition of the additives, seasonings and spices, this method is also troublesome in that it requires the addition of egg yolk and the addition of vinegar and salad oil which must be weighed accurately and that the latter addition must be effected in two stages. In addition, this method requires a special stirrer (for example, equipped with a rotatable net) for stirring the ingredients. As compared with the conventional production of homemade mayonnaise, the use of the mayonnaise base is not so advantageous though not requiring the addition of seasonings and spices to the base.

Mayonnaise base and method for producing it


The invention relates to a four-joint wiper arm for a windshield wiper system of a motor vehicle, with the so-called four-joint consisting of a primary lever that can be connected to the primary shaft, a control lever arranged lateral to the former, that can be connected to a supporting arbor and a coupling link connected by means of one joint respectively to the free ends of primary lever and control lever. At the end at which the control lever is coupled, the joint section of the wiper arm is pivoted to the coupling link in a conventional way. In order to preclude distortion in the four-joint assembly and thereby improve the wiping quality, one of the two joints is in the form of a ball-and-socket joint between the coupling link and primary lever or control lever and the other is in the form of a universal joint.

The invention relates to a four-joint wiper arm for a windshield wiper system of a motor vehicle, with one joint formed between a primary shaft and a primary connecting rod, an additional joint formed between the primary lever and a coupling link, an additional joint formed between the coupling link and a supporting rod and an additional joint formed between the control lever and a supporting arbor.
Four-joint wiper arms of this type, for which the curved wiping movement of the wiper blade on the windshield is combined with an additional lifting movement in the longitudinal direction of the wiper blade, are known, e.g., from DE 4,214,679 A1 or EP 0,537,059 A1. In both cases, both the primary lever as well as the control lever are connected to the coupling link by means of a respective one arbor, with both arbors running parallel to each other and perpendicular to the pendulum plane of the coupling link. It is known that the wiper blade must be pressed against the windshield to be wiped with a force great enough to achieve a good wiping quality. The pressure force of the wiper blade is produced by means of a prestressed tension spring, the ends of which are secured to the wiper rod or joint section, on one hand, and to the coupling link, on the other hand, in such a way that the joint section with wiper arm, which is sealed on the coupling link so as to pivot, is moved relative to the coupling link in the direction of the windshield.
Upon contact of the wiper blade against the windshield, a tension produced by spring tension force is transmitted by the pivot bearing between joint section and coupling link into the four-joint assembly. This leads to distortion between the parts of the four-joint assembly, especially in the four pivot bearings. This stress leads, in turn, to an obstruction of the wiping movement, lessening the wiped quality. Distortion in the four-joint assembly also occurs, more specifically, if the four aforementioned joint locations are not mutually aligned with sufficient precision, which can be caused by manufacturing tolerances alone.

Four-joint wiper arm for a windshield wiper system of a motor vehicle


A method for halftoning a gray scale image to generate a halftoned image uses a stochastic screen is designed to provide visually pleasing, blue noise dot profiles when thresholded at any gray level and wherein substantially all the threshold values corresponding to gray levels between gs1 and gs2 coincide with black positions in a constraining checkerboard pattern and substantially all the threshold values corresponding to gray levels between gs2 and gs3 coincide with white positions in the constraining checkerboard pattern.

The present invention is directed to a method and apparatus for halftoning images, and more particularly, to the generation of stochastic screens for use in halftoning digital images.
In the digital reproduction of documents, images are conveniently represented as one or more color planes or separations that can be combined at printing to yield a color print. Each image separation is an arrangement of pixels each of which corresponds to a different location of the image and describes the image density at that location. Typically an image separation comprises a raster image which may be described as an of array pixels. Image density typically is described as one level in a number of possible states or levels. Commonly, color documents are formed using one separation describing density for each of a cyan, magenta, yellow and black colorant; although a larger number and/or alternative colorants may also be used.
Most printing systems have the ability to reproduce an image with a small number of levels, most commonly two, although other numbers are possible. On the other hand, common input devices are capable of describing an image with a substantially larger number of gray levels, with 256 levels a commonly selected number, although larger and smaller levels are possible. When more than two levels of density are used in the description of the image, the levels are often termed "gray", indicating that they vary between a maximum and minimum, and without reference to their actual color. Thus, given an image or a separation in a color image having perhaps 256 possible density levels, a set of binary printer signals must be produced representing the continuous tone scale of the input image. In such arrangements, digital halftoning or screening techniques in which digital input signals to a digital printer are modified prior to printing a hard copy are used such that a digitally printed version of a continuous tone scale image, e.g., a photographic image, creates the illusion of the continuous tone scale of the photographic original.
Typically, digital halftoning or screening techniques control the printing of spots to obtain the illusion of continuous tones based upon a comparison of the required shade of gray with one of a set of predetermined threshold levels. That is, over a given area in an image separation, each pixel in an array of pixels within the area is compared to one of a set of preselected thresholds such as is taught, for example, in U.S. Pat. No. 4,149,194 to Holladay. If the pixel value exceeds the given threshold level (the gray level is darker), a spot is printed. If the gray is not as dark as a given threshold level, a spot is not printed.
One type of screen that has been found to generate nice halftone patterns is a stochastic screen. A stochastic screen produces dots with a random nature, and its halftone patterns can be less visible than structured halftone patterns produced by traditional ordered dither. For most input levels the outputs of stochastic screens have "blue-noise" spatial spectra which provide pleasant appearance. Various methods exist for generating stochastic screens. One method of making a stochastic screen is to start with a stochastic halftone pattern at a certain level, and then use a low-pass filter to find the largest "voids" or "clusters" and reduce them to generate the halftone patterns for the remaining levels, and when all the levels have been visited, a stochastic screen can be generated by combining the halftone patterns of all levels.
Additional information on halftoning systems using a stochastic process known as a blue noise mask can be found in a family of patents to Parker et al., including U.S. Pat. Nos.: 5,111,310; 5,323,247; 5,341,228; 5,477,305; 5,543,941; 5,708,518; 5,726,772. Briefly, a blue noise mask can be generated as follows. Starting at a first gray level with a chosen dot pattern, or "seed", the process iteratively uses a Fast Fourier Transform (FFT) techniques with a "blue noise" filter to redistribute all spots in dot pattern and eliminate large visual "clumps." Next, the dot pattern is processed at the next gray level by increasing (or decreasing) certain number of black spots on the previously determined dot pattern (existing black (or white) spots are not moved). The same filtering technique is used to distribute newly added (or subtracted) dots. The above processing is then repeated for all gray levels sequentially. At each step, the width of the blue-noise filter varies by an amount corresponding to the current gray level. The summation of dot patterns for each gray levels is the blue noise mask generated.
Stochastic screens have been shown to provide good image quality in printers that use ink, such as solid ink printers and ink jet printers, which can print isolated dots reliably and accurately. However, when dot positioning is less accurate or reliable, halftone noise can be quite objectionable resulting in a noticeable reduction of image quality. Dot placement error often increases when the firing frequency of the jets increases. As the firing frequency goes up, there is more variation as to where the dots are placed. There are a variety of factors that can contribute to dot positioning errors. For example, inconsistencies and/or contaminants in the ink as well as the use of different inks may vary the flow rate in the print head, cause the ink to foul or clog nozzles in the print head, or change the thermal characteristics of the ink. Each these can result in variations in the amount and the location of ink deposition. Additionally, a variety of manufacturing flaws can impact the rate ink flows through or discharges from the print head; thereby resulting in inconsistent and inaccurate drop placement.
Another factor that contributes to the noise level in stochastic halftoning is the interaction between neighboring dots, which can be quite non-symmetric. For example, for some inks such as many of those with solid ink printers, dots can be congealed in a way that is very difficult to characterize. Even when two dot patterns are geometrically symmetric, they can have different visual effects. Furthermore, inconsistencies and/or contaminants in the ink also impact the way dots congeal as well as dot-to-dot interactions (such as agglomeration); thereby adding further complexity and unpredictability to the process. These printer artifacts, dot positioning errors and unfavorable dot-to-dot interaction, can combine to increase the noise level in stochastic halftoning on certain printers.
Thus, there is a desire to construct a halftone screen which exhibits robustness against printing artifacts such as frequency dependent dot placement and dot-to-dot interactions (such as agglomeration) while maintaining the favorable characteristics of a stochastic screen.