A lamination shaping apparatus has a powder layer preparing means and an optical unit which irradiates a light beam to an intended portion of a powder layer so as to sinter or melt for solidifying the portion into a cured layer. Preparation of the powder layer and curing of the cured layer are repeated to fabricate a three-dimensional object in which a plurality of the cured layers are laminated and integrated. The apparatus includes a fixed base carrying thereon the powder layer and the cured layer, an elevator frame surrounding a periphery of the fixed base, and driving means for driving the elevator frame to move vertically. The powder layer is formed within a space above the base and surrounded by an interior surface of the elevator fame such that the powder layer (cured layer) can be stacked on the base with the base being kept at a fixed position, thereby facilitating to fabricate a precisely shaped object.

There is already proposed a process of fabricating a lamination object known as a selective powder sintering lamination. The process includes a step of forming a powder layer of inorganic or organic powder, and a step of irradiating a light beam to an intended portion of the powder layer to sinter or melt for solidifying it into a cured layer, these steps being repeated to fabricate the object in which a plurality of the cured layer are laminated and integrated. Japanese patent publication JP2002-115004 A (patent document 1) discloses, in addition to the above, to provide a step of grinding a surface of a precursor of the object between the repeated curing steps of forming the curing layers in order to give a smooth finish to the object of various shape at a low cost.
However, the above prior art sees a drawback as to accuracy of the laminated object. That is, in order to successively forming the thin powder layers, as shown in FIG. 22, a shaping section is composed of a shaping stage 61, an elevation mechanism 62 for elevating the shaping stage 61, and a shaping frame 63 surrounding the shaping stage 61. Further, a powder supplying section is composed of a tank 65, an elevation mechanism 66 and an elevation table 67 for lifting the powder material in the tank, a supplier blade 68 for feeding the powder material from the top of the tank onto the shaping stage 61 and smoothening the powder material.
With this arrangement, the powder layer on the shaping stage 61 is sintered or melted at a predetermined portion to be solidified into the cured layer, and a subsequent powder layer is formed by lowering the shaping stage 61 and lifting the elevation table 67 by one step followed by moving the supplier blade 68. However, since the shaping stage 61 carrying thereon the object is made movable, the precursor of the object is likely to suffer from a minute positional fluctuation during the course of irradiating the light beam to sinter or melt for solidification, or using a milling machine for grinding, which makes it difficult to precisely fabricate the object having the order of micrometers.
Further, the elevation mechanism 62 and 66 for elevating the shaping stage 61 and the elevation table 67 have to be disposed below the stage 61 and table 67. With this result, the shaping section has a total height of H more than doubled an elevation range H1 of the shaping stage 61 (and elevation table 67), making it difficult to reduce the total height of the apparatus. In the figure, H2 indicates a driving range of the elevation means 62(66).    [Patent document 1] JP 2002-115004 A


A method for switching from a first communication interface to a second communication interface on a terminal in the process of communication. This method includes the following steps: detecting a number of commands to implement a process of replacing missing samples while audio of the communication is being decoded; and switching to a second communication interface when the number of commands exceeds a threshold. Also disclosed are a device and communication terminal implementing the method as described.

The communication network makes it possible for example to access telephony or video telephony services on a mobile network.
Telephony and video telephony services on 2G and 3G mobile networks use "circuit-switched" technology, called CS (circuit switching).
For the last few years, with the advent of 4G mobile networks, operators have begun to deploy IMS (for "IP multimedia subsystem") architectures, making it possible to provide their clients with VoLTE/ViLTE (VxLTE for "Voice services over Long Term Evolution") services, that is to say voice and video telephony services using IP technology.
Moreover, to cover lack of 2G, 3G or 4G radio coverage, operators have decided to offer their clients VoWiFi/ViWiFi (VxWiFi) services, that is to say voice and video telephony services that also use an IMS architecture, but whose voice transport is performed over Wi-Fi radio technology.
VxLTE and VxWifi services both use "packet-switched" technology, called PS, and the same IMS core network.
Voice communication may be established indiscriminately by way of a Wi-Fi, 4G or 2G/3G access network.
Wi-Fi technology is not optimal for voice transport. In the event of strong constraints or demands on the Wi-Fi radio, attempts to prioritize voice over other data do not make it possible to keep good quality of the voice signal.
The Wi-Fi radio link may be shared by several active access points in one and the same geographical area, which may deteriorate the quality of the transported voice. Likewise, for one and the same Wi-Fi access point, the radio frequency band may be shared between several appliances connected to this point and, depending on the traffic caused by these appliances, the quality of the transported voice may be degraded. In addition, as Wi-Fi coverage is limited in terms of distance, the quality of the communication may also be degraded upon moving away from the Wi-Fi access point. Interference may also be caused by nearby appliances implementing other radio technologies using the same frequencies, such as for example Bluetooth and NFC technologies. Some household appliances, such as microwaves, may also generate interference by using frequencies common to the Wi-Fi radio.
To rectify this problem of quality of voice over Wi-Fi, there are mechanisms for switching over between a Wi-Fi network and a 4G network that are based on analyzing the level of the radio signal or else on the loss of Wi-Fi packets. Some terminal manufacturers completely prohibit the use of voice over Wi-Fi (VoWiFi) on certain access points that are deemed to be incompatible.
For example, published patent application US20090010222 describes a method for switching over from one network to another on the basis of the RSSI (for "received signal strength indication") level, measuring the strength of the Wi-Fi signal.
This mechanism along with other mechanisms from the prior art are based on analyzing the Wi-Fi network, and do not take into account the quality actually perceived by the user. Now, the correlation between the quality of the Wi-Fi network and the quality actually perceived by the user is not direct.
There is therefore a need for a solution for taking into account the quality of the communication perceived by a user in order to switch over from one communication network to another, or more generally from one communication interface to another.

Switchover from a first communication interface to a second in order to improve the perceived quality of the communication


The present invention provides a floating-plate connector assembly which includes a mounting plate on which are mounted a combined power and signal pin connector, an alternating current connector and a pair of guide pins. The mounting plate is in turn mounted on the rear panel of a power supply module so that the connector plate may move within predetermined limits in two axes. The floating-plate connector assembly blind mates with a printed circuit board located within a power supply chassis. The present invention also provides a power supply system having means for securing power supply modules to the chassis that includes a handle which is pivotably connected to the power supply. The handle includes a cam and teeth which respectively engage a notch and apertures located on the base of the chassis when rotated in a first direction. The power supply module is disengaged from the chassis when the handle is rotated in a second direction opposite to the first direction. The present invention also provides a mounting assembly for securing a printed circuit board in place in a chassis without the use of removable fasteners. In addition, the present invention provides an assembly for securing a faceplate to a chassis without the use of removable fasteners. The power supply system of the present invention also provides a brake lever assembly which facilitates the securing of a power supply system to a fixed location while providing the option of mobility.

1. Field of the Invention
The present invention relates to power supply systems, and more particularly, to a modular power supply system having a unibody chassis for housing two blind-mating power supply modules which are interconnected to a system via a printed circuit board assembly. The chassis and power supply assembly of the present invention facilitate quick and convenient installation, removal and replacement of the power supply modules and printed circuit board.
2. Description of the Related Art
Over the past decade, personal computer systems have significantly increased in performance. Along with this advance is the need for continuously and reliably supplying power to the computer system so as to minimize loss of data and to provide continual access to the computerized information. Typical computer systems are serviced by a single power supply module, which acts as a single point of failure in the event that the power supply module malfunctions, causing delay and user down time. In addition, while systems exist which allow the user to replace a malfunctioning power supply module with a functioning unit by simply plugging in the new unit, in most cases, the new unit cannot be directly plugged in while the system is running and plugged into an alternating current outlet, and thus the power supply module is not hot swappable.
Accordingly, there is a need in the technology for a power supply system which provides power supply modules which not only are redundant and hot swappable, but are also easily accessible and blind-mated to a printed circuit board assembly.
Most computer components such as power supplies and printed circuit boards are mounted to the housing or chassis by means of fasteners such as screws. These removable parts are candidates for upgrades and replacements and, as a result, need to be easily accessible. In many cases such as this, the use of removable fasteners (like screws) creates a dangerous situation as the fasteners may easily fall into and cause shorts in components such as drives, power supplies, or circuit boards during installation and removal.
In addition, while power supply-related problems are often easily isolated to a specific component, removal of the component generally involves the removal of mounting fasteners, such as screws, and the disconnection of electrical connectors, which creates additional inconvenience and delay. Moreover, the new or reconditioned power supply component must be manipulated into place within the chassis and must be aligned properly so as to be installed correctly. Such removal and installation increases the amount of time required to service the power supply components, resulting in higher service costs and greater delay in servicing.
Thus, there exists a need in the technology for a power supply system having a single strong chassis which houses and secures all components such as power supply modules and the requisite printed circuit boards, while facilitating quick and convenient removal, replacement and upgrade of the power system.
Finally, computer systems that include redundant power supplies and other computer components are typically housed in a chassis that is not easily movable. This is a precaution to minimize damage to the computer components when the computer system is being moved. However, in an office environment, a computer system which functions as a server may need to be relocated several times during its useful life. As such, there is a need for providing a computer system that is robust and movable and which also can be reliably secured once it is positioned.

Modular, redundant, hot swappable, blind mate power supply system


A circuit for a low-power and blocker-tolerant mixer-amplifier stage may include a complementary mixer formed by transmission gates having complementary structures. The complementary mixer may be configured to receive one or more radio-frequency (RF) signals and to convert the one or more RF signals to intermediate frequency (IF) current signals. A complementary TIA may be coupled to the complementary mixer and may be configured to receive the IF current signals and provide IF voltage signals. The complementary TIA may be formed by coupling an NMOS-TIA and a PMOS-TIA to a common load. A first portion of the complementary mixer may be coupled to the NMOS-TIA and a second portion of the complementary mixer may be coupled to the PMOS-TIA.

As the number of wireless standards and the range of frequencies of wireless communications continue to increase, there is an increasing need for communication receivers that are capable of handling multiple wireless standards spanning a wide range of frequencies. Also, as the number of wireless devices and the amount of wireless communications taking place increase, the communication receivers may have to be able to function satisfactorily in the presence of large amounts of noise and interference.
Further, the multitude of battery operated wireless devices has created a demand for extremely low-power transceivers to increase the handset talk time and to reduce the battery size and ultimately the cost. Meanwhile, the noise and linearity requirements are becoming more stringent to meet the quest for higher data rates with a highly congested spectrum. Typically, implementing low-noise receivers may become more challenging when the design objectives also include low-power consumption and larger blocker signal tolerance.
Therefore, the need exists for low-power and low-noise receivers that can tolerate larger blocker signals.

Receiver architecture with complementary passive mixer and complementary common-gate tia with low-noise gain control


A method for fabricating very narrow contacts on semiconductor substrate for increasing the packing density of devices on Ultra Large Scale Integration (ULSI) circuits was achieved. The method involves using conventional photolithographic techniques and anisotropic plasma etching to etch openings in a conducting layer and partially etch into an underlying planar insulating layer that covers and isolates the devices and device contact areas. Another conformal conducting layer is deposited on the substrate and in the openings and then etched back to form sidewall spacers in the openings. Using the original conducting layer and the sidewall spacers as an etch mask, the planar insulating layer is anisotropically etched within the sidewall spacers to form very narrow (small) contact opening to the desired device contact areas. Still another conducting layer is then deposited to fill the very narrow contact openings making electrical contact to the device contact areas, and then the conducting layers are patterned to form the next level of connecting metallurgy.

(1) Field of the Invention
This invention relates to semiconductor integrated circuit devices, and is directed to a method of forming small (sub half-micrometer) contacts to devices on semiconductor substrates for Ultra Large Scale Integration (ULSI) circuits. More specifically, the method achieves higher packing density of storage cells on dynamic random access memory (DRAM) chips.
(2) Description of the Prior Art
In recent years, the integrated circuit density on the semiconductor substrate have dramatically increased. This increase in density has resulted from down scaling of the individual devices built in and on the substrate and the interconnecting patterned electrical conducting layers that are used to wire up the devices. Future requirements for even greater increases in packing density is putting additional demand on the semiconductor technologies, such as improved resolution in the photolithography and plasma etching techniques.
One processing area limiting the packing density is the fabrication of reliable small contacts to the semiconductor substrate between the closely spaced discrete devices. And more particularly, it is important to make good electrical contact to the source/drain areas of the field effect transistors (FETS) on integrated circuits chips such as the dynamic random access memory (DRAM), static random access memory (SRAM) and the like. One method of making reliable contacts to the substrate having closely spaced interconnecting wiring is described by J. K. Kim, U.S. Pat. No. 5,358,903, however, the method does not address the concern of making contacts adjacent to devices, such as are required for source/drain areas of FETs.
It is common practice in the semiconductor industry to use self-aligned contacts to the source/drain areas of FETs to achieve tighter design ground rules, and thereby achieving a high packing density on the chip. For example, referring now to FIG. 1, a schematic cross sectional view of a partially completed FET is shown having a patterned photoresist mask 40 for etching a conventional self-aligned contact opening 6 to one of the two source/drain areas 8 of an FET, such as on DRAM chips. FIG. 1 shows a portion of the silicon substrate 10 having an active device area surrounded by a field oxide (FOX) areas 12. A patterned polysilicon layer 16 is used to form word lines 16 on the DRAM circuit with the portion over the active device area serving as the gate electrode 16' of the FET. An insulating layers 20 and insulating side wall spacers 22, composed of, for example, silicon oxide, are formed, respectively, over and on the side of the gate electrode 16' and also on the word lines 16. After forming doped source/drain regions 24, for example, by ion implantation, an insulating layer 26, such as silicon oxide, is deposited on the substrate to insulate the source/drain contacts 24. A patterned photoresist mask 40 and etching is then used to etch the self-aligned contact openings 6, as shown in FIG. 1. When the overlapping contact opening 6 is etched in the insulating layer 26 and the thin gate oxide 11 to the source/drain area 24, the insulating layer 20 and the side wall spacers 22 protect the gate electrode from shorting to the source/drain 24 when an electrical contact (not shown in FIG. 1) is made to the source/drain areas 24 .
Unfortunately, as the device packing density on future integrated circuits continues to increase, such as on the array of storage cells of future 64 megabit, 256 megabit and higher megabit DRAM chips, the lateral dimensions of the spacing between word lines and gate electrodes must further decrease. This leads to a problem in forming the self aligned contacts, as is depicted for a high density chip in FIG. 2. For example, referring now to FIG. 2, when the spacing are reduced to about 0.4 micrometers or less between the word lines 16 and also between gate electrodes 16' over device areas, the insulating layer 26 conformally coats, and thereby fills the spaces between the lines. This forms a planar or almost planar surface on the insulating layer 26. If a conventional self-aligning contact opening 6, is etched using the photoresist mask 40 and anisotropic etching, then the insulating layer 20 and sidewall spacers 22 are unintentionally removed over portions of the gate electrode 16' and word line 16. This occurs since the insulating layer 26 is substantially thinner over the word line than over the source/drain areas 24. This results in electrical shorts between the source/drain area 24 and gate electrode 16' at the points A and B, as depicted in FIG. 2. when the electrical contacts (not shown) are made to the source/drain areas 24.
Therefore, there is still a strong need in the semiconductor industry for forming very small electrical contacts for ULSI circuits that have closely spaced patterned conducting layers in order to avoid the shorting problem. There is also a strong need in the semiconductor industry for making these small contacts using conventional optical photolithographic techniques so as to avoid the added cost required in using more advanced shorter wavelength lithographies, such as X-ray and electron beams.

Small contacts for ultra large scale integration semiconductor devices without separation ground rule

Industrial Technology Research Institute


The invention relates to a process for manufacturing an article of a high-density carbon. To produce an un-fired compact, binderless, self-sintering, fine-grained carbon powder, particularly carbon mesophases, with a powder density of more than 1 g/cm.sup.3, particularly more than 1.4 m/cm.sup.3, and an average grain size of between 5 and 20 .mu.m, is precompacted at a low pressure and is pressed in a mold to at a pressure of between 50 and 150 MPa, particularly at approximately 100 MPa. After pressing, the contact pressure is slowly lowered. Then, the un-fired compact is carbonized in a temperature gradient of maximally 20 K/min. The temperature is held constant at a holding temperature of between 500 and 700.degree. C. for a defined holding time and is subsequently raised to a maximal temperature of between 800 and 1,200.degree. C., particularly approximately 1,000.degree. C. Finally, the carbonized compact is graphitized at an end temperature of between 2,500-3,000.degree. C. in an inert atmosphere, preferably a noble gas and particularly preferably argon and/or nitrogen.

The invention relates to a method for manufacturing a molded article of high density carbon. The article can be pressed from a powder, the un-fired compact is carbonized and then graphitized.
Japanese Patent Document JP 5-221719 (A), discusses a process for manufacturing molded parts from high density carbon. The parts are close to the final desired dimension, have at least one cavity, and are particularly intended for the manufacture of pistons for internal combustion engines. For manufacturing a molded part, an un-fired compact is pressed from a sinterable powder, a powder of a high density and a grain size of an average of 15 .mu.m. The un-fired compact is carbonized by heating to temperatures between 800.degree. C. and 1,200.degree. C. and is then graphitized by heating to temperatures between 2,600.degree. C. and 3,200.degree. C.
To form the un-fired compact, the powder is filled into a pressing mold of a pressing tool, which has a final dome-shaped die. The mold piece provided for forming the cavity in the part is made of a rigid material, particularly of metal. The pressed, un-fired compact is then removed from the pressing tool. To form the finished part, the un-fired compact is then carbonized and subsequently graphitized. To simplify removal of the un-fired compact from the pressing tool, the die has a slight conical shape, which opens up at the end the compact is removed from.
However, the molded parts produced in the manner according to the Japanese document have cracks in the edge areas. Therefore, on the edges, the parts must be made to a high over-dimension compared to the final desired dimension. Thus, in the manufacturing of the final article, increased machine work as well as time and cost expenditures are required. In addition, because of a tendency to break apart, the number of rejects produced from this process is very high, despite the over-dimension used.
To avoid this disadvantage, other documents of the art suggest using a die made of a rubber-elastic material and/or using a non-sinterable powder for producing the un-fired compact. The other working steps, such as the pressing, carbonizing and graphitizing, remain the same. The molded parts obtained by means of this process remain largely free of cracks. However, the time and energy requirement, approximately 20 days to one month for carbonizing the un-fired compact, is very high.
The present invention provides a cost effective process to manufacture articles made of a high density carbon where the manufacturing and finishing is more reasonable with respect to cost. The invention provides a method for manufacturing a high density carbon article that comprises first compacting a carbon powder into a rigid die. The carbon powder comprises a binderless, self-sintering, fine-grained carbon of a density of more than about 1 g/cm.sup.3 and having an average grain size of between about 5 to about 20 .mu.m. Preferably, the carbon content of the carbon powder is greater than about 90% by mass, the carbon powder comprises a mesophase carbon, and has a density of about 1.4 g/cm.sup.3.
Generally, the compacting of the powder into a rigid die occurs at a pressure of between about 50 to about 150 MPa, preferably 100 MPa, the pressure being preferably released slowly. A precompaction step may also be included before pressing the powder into the die. The precompaction step preferably involves shaking the die but may also include uniaxially precompacting into the rigid die and subsequently isostatically pressing or cold-isostatically pressing the powder. Uniaxial compacting and isostatic pressing or cold-isostatic pressing can also be employed for the compacting process. Compacting the powder under pressure forms a compact, or an un-fired molded product.
After the compact is formed, it is subjected to a carbonizing process. Generally, carbonizing involves heating in an inert atmosphere to a temperature of between about 500 to about 700.degree. C. Following the heating to about 500 to about 700 .degree. C., the temperature is raised to a maximum of between about 800 to about 1,200.degree. C. to form a carbonized compact. The inert atmosphere can be a noble gas, such as the preferred argon, nitrogen, or any other suitable inert gas. Also, the carbonizing process preferably employs a temperature gradient to raise the temperature of the compact. That temperature gradient may be interrupted by one or more holding periods or pauses.
Following the carbonizing, the compact is graphitized. Generally, a graphitizing temperature of between about 2,000 to about 3,000.degree. C. is used in an inert atmosphere. Again, temperature gradients, with or without pauses, may be employed.
As understood in the art, the temperature of the heating chamber will be roughly equivalent to the temperature of the compact. As used herein, the temperature of the compact can be the actual temperature of the compact, the temperature of the heating chamber, or the temperature that the heating chamber is set to.
In specific embodiments, the temperature gradients in the carbonizing step is between about 5 to about 20 K/min., especially for raising the temperature of the compact to a maximum of between about 800 to about 1,200.degree. C. or until the compact reaches a temperature of about 150 to about 200.degree. C., or a gradient of between about 0.05 to about 0.5 K/min., preferably 0.1 K/min.
During the graphitizing step, the heating rate of between about 0.05 to about 1 K/min. is preferably used until the compact reaches the temperature of between about 1,400 to about 1,800.degree. C., and thereafter a heating rate of between about 2 to about 20 K/min, preferably 5 K/min., is used. Also during the graphitizing, a gradient up to a first temperature of between 1,400 and 1,800, particularly 1,600.degree. C., at between about 0.05 and about 1 K/min., preferably approximately 0.2 K/min, is used. After reaching that first temperature, a heating rate of between about 2 to about 20, preferably about 5 K/min, is selected.
In addition, the holding period or pause in the gradients can be one where the compact is held at a temperature of between about 500 to about 700.degree. C. for a period shorter than about two hours, or where at least one holding period occurs at approximately 1,600, 1,900, or 2,500.degree. C. in the respective carbonizing or graphitizing steps.
Also, the carbonizing process may optionally include embedding the compact in a heat-conducting material. Various appropriate heat-conducting materials are known in the art that will not disturb the form of the article and will allow the carbonizing process to proceed. In particular, a heat-conducting material may comprise boron nitride and/or is a loose powder bulk material. In addition, the carbonized compact may optionally be cooled before the graphitizing process begins. The degree of cooling is not particularly critical.
The invention also provides articles produced from any of the methods disclosed herein. Numerous applications for high density carbon articles exist in industry. In a preferred embodiment, the article produced can be used as a component in an internal combustion engine or a crucible. In a particularly preferred embodiment, the article is designed for use as a piston in an internal combustion engine, especially an at least partially hollow piston. In such a case, and in other cases where an article having a cavity is desired, the rigid die employed comprises a mold part designed to form the cavity or hollow part of the article. The mold, generally, is comprised of a rigid metal. The invention is not limited to the use of any particular mold or the production of any particular article. However, preferred molds and considerations for the optimum design of a mold are discussed below or are available to those skilled in the art.
For example, various homogeneous, rigid, and externally polished dies, molds, and cores made of steel are known in the art. These dies can be used to form the desired interior contour of the compact, but previously lead to considerable crack formation. However, an article manufactured according to the method of the invention has a surprisingly negligible amount of cracks and likewise negligible bubbles. For this reason, the dimensions of the articles manufactured, particularly on the edges, can better approach the desired finished dimensions. The reduced deviation of the molded article from the final, desired dimensions results in a shorter machining time and therefore lower cost. In addition, it is surprising that as a result of the invention, the time for carbonizing the pressed un-fired compact can be reduced to approximately 5 days. Thus, the energy consumption and also the costs for manufacturing the article can be dramatically reduced.
Generally, the invention involves pressing binderless, small-grained carbon powders into a non-elastic die and a subsequent temperature treatment, to produce an isotropic article of a high-strength graphite, which is close to the final desired form. Various degrees of closeness to the final desired form may be possible. However, the invention reduces the time-consuming and cost-intensive finishing operations required of prior methods. A suitable powder selection, shaping, and implementation of the process permit the manufacture of homogeneous, crack-free and bubble-free components made of graphite. Thus, depending on the component desired, various permutations in the carbon powders, mold, temperatures used in the steps of the method can be employed by those skilled in the art. Some examples are described below or can be taken from the German priority document. However, the invention is not limited to any particular examples.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.
Although the invention has been described and illustrated in detail, it is to be clearly understood that the same is by way of illustration and example, and is not to be taken by way of limitation. The spirit and scope of the present invention are to be limited only by the terms of the appended claims.
As the staring material, binderless, fine-grained carbon powders, particularly carbon mesophases of a powder density of more than 1.4 g/cm.sup.3, are used. The powder is self-sintering and is processed without any additional additives or binding agents. The average grain sizes of the powders used are between 5 and 20 .mu.m. In addition, powders of high carbon contents of approximately 90% by weight are suitable because they result in a high carbon yield after carbonizing.
Pressing the un-fired compact close to the final form may take place either in a cold isostatic press or in a uniaxial press. The cold-isostatic forming tool used, into which the powder is filled, consists of a unvulcanized rubber-type material, such as silicon rubber or a PU-foam material, with a wall thickness of between 5 and 15 mm. A die made of a rigid, non-elastic material is added to the center of these cylindrical forms in that the die is slightly sunk into the bottom of the rubber-type form and cannot slip when the form tool is filled with powder and during the pressing. The die used here results in a cavity in the final product. So that the wall thickness of the un-fired compact to be pressed is approximately the same everywhere, the shape of the forming tool is constructed to be approximately equidistant to the wall of the die.
An advantageous design of the die was found to be a slightly conical shape because, by means of the pressing operation, the powder is pressed onto the die and adheres slightly. Using even a slight conical form or slope in the die significantly simplifies the removal of the un-fired compact after the pressing. This applies particularly to dies which have no rotational symmetry.
The powder is filled into the remaining cavity between the die and the rubber-type form and is slightly compressed manually or by shaking in order to achieve a good filling ratio. The filled mold is closed by means of a lid, which also consists of a rubber-type material, and has the same wall thickness as the rest of the forming tool.
During cold isostatic pressing, the pressure used, as a function of the grain size and of the density of the powder used, is between 50 and 150 MPa. The maximal pressure is maintained for up to 10 minutes.
During the pressing process, it is advantageous to control the pressure reduction from approximately 8 MPa to the normal pressure in order to avoid pressing tensions in the component. During the pressing, the die remains in the center of the rubber-type form filled with powder and is also pressed and supplies a true-to-form interior contour of the cavity. By means of this operation, a clean and smooth contour and interior surface of the pressed compact is obtained. In contrast, in the case of the cold isostatic pressing, the exterior walls of the pressed un-fired compact are slightly curved because, during the pressing onto the non-deformable core, the powder flows plastically into the corners of the rubber-type form where the pressing forces acting upon the form are not so strong.
In order to also construct the outer contour close to the final form and for industrial scale applications, it is advantageous to press the un-fired compact uniaxially. In the case of a uniaxial pressing in a rigid cylinder and when a rigid core is used, not only the interior contour but also the exterior contour can be produced close to the final shape. The wall surfaces produced are smooth, which completely eliminates exterior finishing of the component.
The contact pressure is very dependent on the desired component and is higher than 1 MPa. The pressing mold consists of a metal, such as aluminum, whose surface is coated with a hard material and/or anodized. It may be required to isostatically recompact the uniaxial compacts, for example, by welding and evacuating in a plastic foil. As a result, the exterior contour and the interior contour will change very little, if at all. The un-fired compacts so far produced according to the method of the invention have bottom and wall thicknesses of more than 5 mm.
For the carbonizing, it is advantageous for the un-fired compact to be charged into a crucible, which contains a heat-conducting material, such as boron nitride. The un-fired compact is embedded completely in the loose powder bulk of the heat-conducting material. During the temperature treatment, the material surrounding the mold-part must not react with the product, must not adhere, and must itself not be sinterable. Also, it must be easily removable after the carbonizing.
The temperature treatment is carried out in an inert gas atmosphere, for example, under nitrogen. Up to a temperature of approximately 200.degree. C., a fast heating rate of approximately 10 K/min. can be used. Starting at 200.degree. C., the first compacting step and shrinkage process in the pressed un-fired compact will start. In this case, a slow heating rate of approximately 0.1 K/min. will preferably be selected. In the temperature range between 500 and 700.degree. C., an intermediate holding time expediently takes place so that the material will have time for the chemical reactions to occur and the pyrolysis gas to be released to diffuse to the component surface. Subsequently, a faster heating rate of approximately 0.2 K/min. is used up to the end temperature of 1,000.degree. C. The whole process time amounts to, for example, approximately 4 days.
After the carbonizing, a compact, crack-free body is obtained which, in comparison to the un-fired condition, has shrunk by approximately 30% in volume. The compact carbonized crucible form consists of a partially crystalline, partially graphitized carbon material and is hard and brittle in this condition. The structure of the carbonized compact is homogeneous. The interior contours, which are caused by the pressing operation of the die or onto the core, are obtained in a true-to-size manner.
For the graphitizing process, it is not absolutely necessary to burn the carbonized crucible in a powder bed. The graphitizing of the carbonized un-fired compacts takes place in an inert atmosphere; for example, using argon, and is conducted at temperatures of from 2,000 to 3,000.degree. C., particularly above 2,500.degree. C. The carbonized un-fired compact is taken out of the carbonizing furnace, and, in the cooled condition, is charged into a graphitizing furnace. As a result, contaminations are avoided during the subsequent graphitizing because contamination degassing from the un-fired compact during the carbonizing will remain in the carbonizing furnace. The graphitizing furnace is heated to approximately 1,000.degree. C. with a temperature gradient of approximately 10 K/min. At temperatures of between 1,000.degree. C. and approximately 1,600.degree. C., a heating rate of approximately 0.2.degree. K./min. is selected. Up to the desired graphitizing temperature, heating rates of up to 5 K/min. can be used. Advantageously, pauses are made at temperatures of 1,600, 1,900, and 2,500.degree. C., which are used for improving time-dependent diffusion within the interior of the component, which is advantageous for achieving good material properties of the end product.
During the graphitizing, mainly compacting processes occur in the body volume. In addition, the crystallinity of the carbons will rise considerably and it becomes increasingly graphitic in its properties.
An article produced by means of the method according to the invention is crack-free and homogeneous. The molded part has a homogeneous fine-grained structure and therefore has excellent physical and mechanical properties for a graphite. The surfaces which faced the core during the pressing are smooth. The volume shrinkage with respect to the un-fired compact is 40-50% by volume.

Process for manufacturing a molded article made of high density carbon


Aspects of a method and system for a Bluetooth headset with a clock are provided. A Bluetooth headset may have an access to real-time clock information such as a real-time clock value at a specific time instant and generate corresponding audio and/or visual representations to a user via Bluetooth communication. The real-time clock information to the Bluetooth headset may be originated within or external to the Bluetooth headset. The timing of the real-time clock of the Bluetooth headset may be maintained by a Bluetooth clock of the BT headset. The Bluetooth headset may provide respective real-time updates by pressing a button on the Bluetooth headset or from timing events such as calendar entries or personal alarms downloaded into the BT headset from a Bluetooth device, and/or from timed Bluetooth messages communicated to the Bluetooth headset from the peer device.

Bluetooth is a technology standard for short-range wireless connectivity between all kinds of mobile or stationary electronic devices, such as cellular phones, cameras, PDAs, wireless headsets, laptops and/or computers. The Bluetooth wireless technology operates via a radio transceiver in a globally available license-free frequency band, ensuring communication compatibility worldwide. Bluetooth chips are small, low-cost modules, which are built into devices, allowing a fast and secure transmission of voice and data through a radio link.
Bluetooth is a low-cost wireless technology that enables users with Bluetooth-enabled devices, such as headphones and/or speakers, to communicate voice and data over a very short range. For example, a Bluetooth headset or Bluetooth speakerphone paired with a cell phone may allow hands free communication via the cell phone. In this regard, the user does not have to hold the phone to their ear during a call, but instead using a Bluetooth enabled headset or speakerphone for listening and/or speaking. The user is therefore free to perform other activities.
A growing number of mobile users rely on their cell phones to provide time. As a result, many mobile users do not wear a watch. Even in instances where a mobile user may be wearing a watch, the watch may be concealed under clothes such as a short or jacket. Accordingly, there may be instances when it may be inconvenient to determine the time from their watch. With the advent of Bluetooth headsets, a growing number of cell phone users keep their cell phone in their pockets, in a bag, in a pouch, and/or strapped to their belts. Hence, it may sometimes be inconvenient to retrieve the cell phone to determine the time.
Further limitations and disadvantages of conventional and traditional approaches will become apparent to one of skill in the art, through comparison of such systems with the present invention as set forth in the remainder of the present application with reference to the drawings.

Method and system for a wireless headset with a clock


A wire-cut electrical discharge machine for machining a workpiece using a wire electrode tensioned between a first and second wire guide, in a state where the gap between the wire electrode and the workpiece is filled with a machining fluid, is provided with a work tank (WT) which holds the workpiece (WP), a guide mechanism (N) which guides the movement of a first wire guide (14) in an X-Y plane formed by mutually perpendicular X and Y axes arrayed within the work tank, and a sealing member (16) which covers the guide mechanism (N) and blocks against leakage of machining fluid from the work tank (WT); the sealing member (16) is connected to a pressurized fluid supply device (401, 402, 403, A1, A2) for the purpose of supplying a pressurized fluid therein, and the pressurized fluid supply device responds to a signal from a sensor (404) mounted on the sealing member (16) which detects fluid pressure, thus regulating the pressure inside the sealing member to be the same as the external fluid pressure of the pressurized machining fluid.

Generally, in a wire-cut electrical discharge machine, a pair of upper and lower wire guides is used to tension the wire electrode, with the lower wire guide positioned below the workpiece. Discharge energy is applied to the wire electrode while supplying machining fluid to the gap formed by the workpiece and the wire electrode, thus wire-cut discharge machining the workpiece. Such wire-cut electrical discharge machines include, for example, the "submersion-type" wire-cut electrical discharge machines, in which wire-cut electrical discharge machining can be performed with the workpiece submerged in the machining fluid within a work tank. In this type of wire-cut electrical discharge machine, when performing electrical discharge machining on a workpiece submerged in the machining fluid within a work tank, the movement of the lower arm which supports the lower wire guide is limited by the side wall of the work tank. As a result, the range of movement of the lower wire guide becomes extremely narrow, and the dimensions of the machinable workpiece with respect to the dimensions of the work tank are reduced, requiring tanks which are quite large in comparison to the size of the machinable workpiece. This is the primary factor preventing the size reduction of wire-cut electrical discharge machines. The same problem arises when wire-cut electrical discharge machining the workpiece either while directly flushing the machining gap with machining fluid or while submerging the gap in machining fluid. A wire-cut electrical discharge machine amenable to size reduction is proposed as a solution to the above described problems in Japan Laid Open Patent Publication 60-52223, whereby a mechanism is provided to enable the movement of the lower arm along the long walls of the work tank while permitting the lower arm to penetrate the work tank side wall. In a wire-cut electrical discharge machine of the above-described configuration, in which the lower arm penetrates one of the work tank side walls, the difference between the work tank dimensions and the maximum machinable workpiece dimensions can be reduced. However, absolutely smooth movement of the lower arm is hindered by the sealing device placed between the lower arm and the work tank side wall, which is used to prevent leakage of machining fluid. The sealing device tends to apply a lateral force due to the movement of the lower arm with respect to it, producing the problem of reduced machining accuracy. Also, in that type of sealing mechanism, the sealing member can easily become degraded by the rubbing effect associated with lower arm movement, requiring frequent maintenance and inspection, creating a separate problem of new costs associated with the maintenance and inspection needed to maintain a given performance over time.


A light source module includes a light-emitting device, a wavelength conversion device and a polarization and color separation unit. The light-emitting device provides an excitation beam including a first portion beam having a first polarization direction. The wavelength conversion device includes a first wavelength conversion area and a polarization conversion area. When the first portion beam irradiates the first wavelength conversion area, the first portion beam is converted into a first color beam. When the first portion beam irradiates the polarization conversion area, the first polarization direction of the first portion beam is converted to a second polarization direction. The polarization and color separation unit is disposed between the wavelength conversion device and the light-emitting device, and transmits the first portion beam with the first polarization direction, and reflects the first portion beam with the second polarization direction and the first color beam to the same direction.

1. Field of the Invention
The invention relates to an optical device. Particularly, the invention relates to a light source module and a projection apparatus.
2. Description of Related Art
With development of display technology, in a projection apparatus, besides that an ultra high pressure lamp (UHP lamp) suitable for emitting a white light can be used together with a color wheel to sequentially generate a red light, a green light and a blue light, so that the projection apparatus can provide color images. In recent years, the projection apparatus using light-emitting diodes (LEDs) as light sources is further developed. However, since the light-emitting efficiency of an LED has limitation, some technicians use a mixed light source design in the projection apparatus to enhance a luminance of the projection apparatus. A commonly mixed light source is, for example, composed of LEDs and a laser light source.
In detail, in a design of the mixed light source, a blue laser is used to excite a green fluorescent powder on a color wheel, so that the blue laser is converted into a new green light source, and in collaboration with a light combining system, the converted green light source is combined with a blue light and a red light provided by the LEDs to provide an illumination light source required by a projector.
Moreover, in some designs of a light source system, the blue laser is used to excite fluorescent powder of different positions on the color wheel to respectively generate a red light and a green light. Transmission paths of the green light and the red light are combined after passing through the light combining system. Since the red light and the green light are generated by using the blu-ray laser to excite the fluorescent powder, such optical design can reduce usage of the red LEDs and the green LEDs. However, in order to use the blue laser as a blue light source of the light source system, those skilled in the art configure a plurality of reflectors in the light source system to guide the blue laser to a transmission direction the same as that of the red light and the green light, and the light combining system combines the light transmission paths. In this way, the number of optical devices is increased, and a whole size of the light source system is increased.
On the other hand, in the optical design of the projection apparatus, based on a light valve, the projection apparatus can be divided into a light source illumination system from the light source to the light valve and an imaging optical system from the light valve to a lens or a screen. The light source illumination system is a non-imaging system, which is mainly used to provide uniform illumination, sufficient color and high conversion efficiency. Moreover, a light source module of the projection apparatus may also have different designs for different purposes. For example, Taiwan Patent No. 380213 discloses a light device including a light source module and an optical lens, and the light source module comprises a plurality of low power light-emitting devices arranged in an array. Moreover, U.S. Pat. No. 7,445,340 discloses a lighting device including an LED light source, an optical device set and a fluorescent material. Besides, U.S. Pat. No. 6,710,921 also discloses a technique related to the illumination device.

Light source module and projection apparatus


An ultrashort pulsed laser instrument is used to perform refractive surgery. The invention operates in ablative and incisional modalities. In the ablative mode, spiral ablation disks (10) consisting of individual laser pulses (40) are produced at high scanning speeds. Ablation profile (11) may be produced in cornea (22) by stacking and arranging multiple ablation disks (10) to produce a specified shape change. Placement of ablation disks (10) is assisted by an optical tracking and control system that compensates for eye motion. A preferred embodiment allows for ablative corrections to be performed on non-planar posterior surface (112) of a laser cut flap affixed to registration platen (120), thereby avoiding exposing the eye interior to high radiant power. Laser cut and contrast agent dyed fiduciary marks (30) may serve as reference features for the optical tracking system. Incisional procedures, such as corneal flaps for LASIK, may also be performed.

1. Field of Invention
This invention relates to the area of human vision correction, specifically relating to the use of short pulse laser beams to precisely remove ocular tissue to change the refractive power of the human eye.
2. Background of the Invention
The invention relates to procedures and apparatus for performing refractive surgery in the central aspect of the cornea to correct refractive errors of the eye. The invention uses ultrashort pulsed laser to perform all aspects of the corneal surgery, including the creation of incisions and the direct ablation of corneal tissue. In particular, the invention replaces the use of UV ablating lasers in procedures such as laser-assisted in-situ keratomileusis (LASIK) with an ultrashort pulsed laser.
Corneal Refractive Laser Surgery
Modern corneal refractive surgery techniques draw upon the original work of Dr. Jose I. Barraquer. Briefly, in 1958, Dr. Barraquer first developed keratomileusis techniques based on the removal of a lenticular volume of corneal tissue by mechanical means. In 1990, Pallikaris et al reported the use of an excimer laser was used to ablate the lenticular volume in the first LASIK cases. The development of LASIK and related procedures is described in Section Three, pages 147-222 of the text book "Refractive Surgery", 2nd edition, 2007, edited by Dimitri Azar.
In the development of corneal refractive correction with lasers, direct ablation of the corneal anterior surface with an ultraviolet (UV) laser was used. An early example is the method of L'Esperance, Jr. in U.S. Pat. No. 4,665,913. The UV laser was typically an excimer laser. The laser ablation was performed with repeated patterns of laser pulses arranged in a specific geometry. The pattern of ablating pulses produced a change in the corneal shape and therefore the refractive power of the eye. This procedure is called photorefractive keratectomy (PRK). The limits of this approach include the fact that direct ablation of the anterior layers of the cornea, including Bowman's layer and the anterior corneal stroma, produce tissue remodeling and a wound healing response that limit and degrade the optical outcome.
Laser-assisted in situ keratomileusis (LASIK) was developed to overcome the limits of PRK. In U.S. Pat. No. 4,840,175, Peyman first detailed the method which later came to be known as LASIK. In LASIK, a mechanical blade first makes a corneal flap cut. Subsequent manual lifting of the flap exposes the inner corneal tissue, referred to as the corneal stroma. The stroma is then subjected to an ablating UV laser beam. The ablating UV laser beam removes a volume of corneal tissue according to a specific mathematical prescription for producing the desired curvature change. In a later development, Munnerlyn in U.S. Pat. No. 5,163,934, employed a difference of sphere formulation to determine the lenticular volume to be removed for a treatment of myopia. The success of LASIK was swift, but used a two-stage, two-instrument procedure. A significant limitation of LASIK is the reliability, precision and quality of the blade cuts to produce the corneal flap. A second limitation is the requirement that nomograms be developed to compensate for the biological response to ablation, and to the geometry-dependent efficiency of UV laser ablation of the corneal stroma. A third limitation is that the low spatial frequency of the ablation patterns realizable with excimer laser ablation. That is, the lateral size of the ablation compared to the ablation depth of a single pulse makes it difficult to stack pulses in a way that allows for arbitrary ablation profiles. Typically, the profiles in LASIK and PRK vary slowly, which from a visual outcomes point of view is rather good. However, if a small amount of tissue is to be removed, such as may occur in a complication of refractive surgery, of if a higher order aberration is to be corrected by removal of a volume of tissue having relatively steeply angled features, large spot excimer ablation may not be efficacious.
LASIK and PRK are performed using a UV laser, typically an excimer laser, to perform the ablative part of the procedure. Examples of excimer laser keratomes include the Visx Star S4 from Abbott Medical Optics, Santa Ana, Calif.; the Technolas 217A from Technolas Perfect Vision GmbH, Munich, Germany; or the LADARVision 4000 and the Allegretto Wave from Alcon Laboratories, Inc., Fort Worth, Tex.
An alternative to LASIK and PRK was suggested and developed by Bille and Juhasz in U.S. Pat. No. 4,907,586 and further refined in U.S. Pat. No. 5,993,438. In this method, a focused ultrashort pulsed laser beam is scanned inside the cornea to create a defined volume of vaporized tissue consisting of many individual small-scale photodisruptions. The volume of tissue would be vaporized and ultimately resorbed by the surrounding corneal tissue. The resulting new corneal shape would produce the desired refractive correction. This approach is referred to as intrastromal or intrastromal ablation. A picosecond laser instrument by Intelligent Surgical Lasers was developed for this procedure. Limitations to the method were several. One limitation is the relatively large volumes of vapor produced in the stroma which limit the amount of tissue that can be destroyed or removed. A second limitation is that the vaporization of tissue for the purpose of altering the shape of the cornea through relaxation of the overlying anterior surface survace is limited by the natural stiffness of the corneal membranes. The native stiffness of the corneal limits the size of the refractive change that can be produced in this method.
Ultrashort pulsed lasers were commercially introduced into corneal refractive surgery with the development of femtosecond laser flap cutter instruments. Mourou et al in U.S. Pat. No. 5,656,186 described a method for using femtosecond pulses which allows for a more deterministic and precise machining of materials, including biological tissues, relative to picosecond lasers. Femtosecond lasers assist in the LASIK procedure by replacing the mechanical microkeratomes used in the corneal flap cutting step. The corneal cuts produced are precise and can have arbitrary three dimensional shapes, surpassing what can be achieved with mechanical blades. A limitation of the approach is that the actual refractive correction still requires the use of a second laser, namely an excimer laser.
Incisional ultrashort pulsed laser keratomes generate, process and deliver a train of scanned, tightly focused ultrashort laser pulses onto or into the volume of a fixed or immobilized cornea. The laser sources used generally employ a chirped pulse amplification technique with a large bandwidth lasing medium, such as Ti:S, Nd:glass or Yb:fiber. Typically, the laser pulses energies range from 0.1-10 microJoules, the pulse widths are <1 picosecond, the beam quality is near-diffraction-limited, and the wavelength falls between the NIR and the visible (typ 800-1100 nm) so as to avoid significant heating of water or tissue by linear absorption in the corneal tissue. Commercially available instruments operate at laser repetitions between 30 kHz and 2 MHz, depending on the design, model and manufacturer. A high speed 2D beam scanner in combination with a high numerical aperture focusing objective allows for the precise placement of tightly focused spots throughout the volume of the human cornea. In a typical femtosecond laser keratome the cornea is fixed with respect to the keratome optical axis and the cornea is lightly held in place and applanated by a contact glass and suction ring.
A purely incisional approach to refractive surgery using a single ultrashort pulsed laser instrument was taught by Juhasz in U.S. Pat. No. 6,110,166. In this approach, multiple laser cuts define a disk-shaped block of corneal stromal tissue underlying a laser-cut flap. The flap is manually lifted and the disk-shaped corneal plug or disk is manually removed. When the flap is replaced, the change in the corneal shape resulting from the missing corneal tissue lenticle produces an appropriate change in refractive power. This change can be accomplished without the need for an ablation step by a UV laser. The approach was similar to an earlier refractive surgery performed with a mechanical blade. The mechanical approach was called automated lamellar keratoplasty or ALK, introduced by Ruiz et al in U.S. Pat. No. 5,133,726. A limitation of both the ALK and the femtosecond laser keratomileusis procedure was the relatively poor refractive outcomes associated with removing a disk of planar geometry, rather than a disk of the ideal lenticule shape according to Munnerlyn and others.
An improved approach over Juhasz is found in United States Patent Application No. 20080319428 of Weichmann et al. The volume of the stromal disk of tissue to be laser cut and manually removed have anterior and posterior surfaces having curvatures rather than being planar. The invention advantageously allows for the realization of ideal shapes of the tissue to be removed. A limitation is that the tissue to be removed manual after cutting may tear or fragment, and cannot easily be removed by laser or by other means. A related limitation is that the axial thickness of the tissue to be removed may be associated with a minimum thickness. Some refractive corrections may require cutting a thin cross section volume of tissue. If the tissue is too thin, it may be too friable. This aspect places limitations on the ranges of potential refractive corrections achievable by this method. A further limitation is that the gas produced in the first portion of tissue vaporized may produce movement or changes in the cornea that interfere with the vaporization of subsequent portion of tissue.
U.S. Pat. No. 4,907,586 also contains a method of corneal refractive surgery in which the optical properties of the cornea are directly altered by a scanning ultrashort pulsed laser. In this method, index of refractive of the targeted volume produces the desired refractive correction. A limitation of this method is the size and stability of the refractive changes to the cornea.
Direct Ablation of Tissue
In LASIK, excimer lasers directly photoablate the corneal tissue they impinge upon. The controlled ablation of corneal stroma tissue produces the desired shape change.
Ultrashort pulsed lasers, such as femtosecond lasers, are widely used to incise cornea through the mechanism of photodisruption. Present clinical use of ultrashort pulsed lasers in the eye employs photodisruption and not the true ablation associated with excimer lasers in cornea. That is, ultrashort pulsed lasers are used to cut cornea rather than ablate it. This is quite sensible in that the natural advantage of using an ultrashort pulsed laser in transparent tissue is that highly localized, small photodisruption events can be arranged to create cut planes or surfaces.
Some confusion exists in the art about the term "ablation". When ultrashort pulsed lasers are used in ophthalmic surgery, the laser-tissue interaction is generally the creation of incisions through the cumulative effect of many individual photodisruption events. In physical processes, ablation refers to the physical processes, such as melting and vaporizing, that result in the ejection of material from the ablation site. The confusion is likely due to the use of the term ablation in medicine. In medical usage, ablation means the localized destruction of tissue, but not usually the physical ejection of tissue through melting or vaporization.
An aspect of my invention is physical ablation of corneal and ocular tissue with ultrashort pulsed lasers. I therefore differentiate between the usage of the term "ablation" in the prior art of ultrashort pulse lasers and the meaning of term is used in my invention. Here, when I use the term "ablation" with ultrashort pulsed lasers, I mean the physical removal of tissue resulting from the laser interaction, whether as a result of a photodisruption event or by some other interaction. Typically I use the term "ablative mode" in this context. When referring to the creation of cuts or incisions, I will use the term "incisional mode".
Two examples of this confusion in terminology are found in Zhang et al ("Morphologic and histopathologic changes in the rabbit cornea produced by femtosecond laser-assisted multilayer intrastromal ablation", IOVS, May 2009, Vol. 50, No. 5.) and Wang et al ("In-vivo intratissue ablation by nanojoule near-infrared femtosecond laser pulses", Cell Tissue Res 2007, Vol. 328:515-520) In the first reference, the authors use the term ablation, but the actual laser-tissue interaction in the cornea was intrastromal photodisruption, which was arranged to create multiple dissection planes inside the cornea. In the second reference, the authors also use the term ablation, but again the laser-tissue interaction was the photodisruptive destruction of corneal tissue on a small scale by nanoJoule laser pulses. True ablation was not occurring in either case.
Certainly ultrashort pulse laser ablation is used in a wide variety of material processing applications. However, the use of ultrashort pulse laser ablation of exposed cornea surfaces for clinical procedures is limited by several factors. An important limitation is the limits placed on input average power and input pulse energy to the cornea by safety considerations associated with non-target tissues such as the retina. A second limitation is the requirements placed on the positioning of a tightly focused laser spot at or near the target surface. This limitation in consideration of available practical ultrashort pulse laser sources results in micron precision in the positioning of the laser focus with respect to the target tissue surface. It is a further limitation that when positioning registration of a focused ultrashort laser beam with respect to a target tissue surface is achieved, very small motion associated with the involuntary movements of the eye may interrupt tissue ablation before a meaningful volume of tissue can be ablated.
Posterior Flap Ablation
The stromal surface targeted for laser ablation is created by manually lifting and reflecting the anterior flap of tissue produced by blade or ultrashort laser cutting. It is generally advantageous to target the exposed stromal bed for excimer laser ablation. In some excimer laser treatments, it may be advantageous to target the posterior surface of the lifted flap instead of the stromal bed. For example, Maldonado retreated LASIK patients by lifting a flap, manually marking the corneal flap anterior surface and manually directing an excimer ablation pattern with the laser keratome eye tracking system turned off ("Undersurface ablation of the flap for laser in situ keratomileusis retreatment", Ophthalmology Vol. 109, No. 8, August 2002). Maldonado marked the posterior flap surface with Gentian violent ink and a hand instrument referred to as a para-radial marker. He relied on visualizing the marked pattern and manually orienting the laser ablation pattern. He noted that a major challenge was stabilizing the eye and flap, and used hand instruments to stabilize the flap, relying on the reflected flap to lie on the eye anterior surface for the ablation. A limitation of the approach of Maldonado is the poor stability of the reflected flap tissue subject to laser radiation. A secondary limitation is the uncertainty in the positioning of the flap posterior surface. These limitations are less important in the case of excimer laser pulse interaction, but are important in the potential use of tightly focused ultrashort pulses, a feature of my invention.
Eye Tracking and Corneal Marking
The corneal is usually marked for refractive surgery. In LASIK or other laser refractive surgery, hand instruments inked with Gentian violet or another biocompatible dye are used to demarcate the corneal center, the optical zone or other orientation information to facilitate the positioning and placement of both the flap cutting keratome and the excimer laser keratome instruments. Marking is typically done by hand or with hand instruments. Marking is used to center and orient the placement of microkeratomes or the placement of excimer laser treatments. A typical hand instrument for marking the cornea in preparation for laser refractive surgery is taught by Kritzinger in U.S. Pat. No. 5,752,967. Further examples of marking instruments may be found in the extensive catalog of manual instruments available from Katena Products, Inc, Denville, N.J.
The biocompatible inks used for corneal marking can be oil-based or water-based inks. Water-based inks—typically a formulation of Gentian violet dye—do not bind strongly to the cornea. In fact, the water-based ink washes off quite easily, and tears, blinking or eye drops can easily fade the markings before the laser procedure. For this reason, oil-based inks are often preferred. According to Ide et al ("Effect of marking pens on femtosecond laser-assisted flap creation", J Cataract Refract Surg 2009; 35:1087-1090), a limitation of oil-based inks is the tendency for the inks to interfere with the transmission of ultrashort or femtosecond laser beams used to create corneal flaps. A further limitation of oil-based inks is the difficulty of removing the inks after the laser procedure is complete.
Laser surgery of the cornea requires precise placement of the laser pulses with respect to the location of the tissue surfaces. Voluntary and involuntary movement of the eye relative to the laser beam optical axis may prevent the desired placement of pulses. Saccadic and slower drifts of the eye may be mitigated by instructing patients to fix their gaze on a distant object or image. The human eye during directed fixation of the gaze exhibits three types of involuntary motion: tremor, microsaccades, and drifts (Physiology of the Eye, Dawson ed., page 663). These movements occur on several time and amplitude scales. Additionally, voluntary or reflexive motion may occur depending on the patient's mental state and environmental stimuli. In corneal refractive laser surgery a need exists to compensate for these movements. These approaches are useful, but insufficient for precision laser surgery of the cornea by excimer lasers, and less useful in ultrashort pulsed laser surgery of the cornea.
A mechanical means to restrain the subject eye may also be used. Restraining the eye generally requires pressure or low vacuum forces to be applied to some part of the anterior portion of the eye globe. The application of such forces can lead to discomfort, injury and surgical complications. Additionally, restraining the eye is not sufficient for all eye motion.
A well-established feature of LASIK and other laser-based corneal refractive surgeries is the detection of, and compensation for, eye movements through the use of eye-tracking technology. Typically, eye trackers employ multiple digital cameras to image high contrast anatomic structures, such as the iris or the pupil edge. Software and firmware processing of the images then produce image registration information that is used to track the motion of defined features. An early example of eye tracking for PRK was taught by Smith in U.S. Pat. No. 5,350,374. Eye tracking may be used passively or actively. Passive eye tracking halts laser treatment when the eye motion ranges beyond an acceptable limit. Active eye tracking continuously compensates for eye motion by re-directing the beam position and angle to match eye movement. A limitation of eye tracking technology with respect to potential use in ultrashort pulsed laser treatments is that the highest speed eye tracking technology available works in the kHz range, or has an equivalent bandwidth. Femtosecond lasers used to incise cornea now operate in the 100's of kHz range. The present invention optimally uses laser sources of pulse repetition rate above 1 MHz pulse repetition rate. A limitation of the existing eye tracking art is that the speed of eye trackers does not match the high repetition rates of ultrashort pulsed lasers that can perform clinically relevant ablation rates in an unrestrained cornea.
An alternative approach is the use of radar technology as in the Ladarvision 4000, Alcon, Inc.
In ultrashort pulse corneal surgery, eye tracking is not performed. The distance tolerances for positioning the focused laser beam and the scanning path of the focus with respect to the corneal surface are high, and are typically on the order of a few microns. The invention taught by Juhasz in U.S. Pat. No. 6,254,595 uses an applanating optic in combination with a "skirt" that uses suction to apply a ring of suction force to the eye. This approach, essentially universal with ultrashort pulsed laser keratomes for corneal surgery, functions well for the incisional modality used presently by all commercial instruments. Applanating optics may be planar, as in the invention of Juhasz, or they may have a curved surface conforming to the shape of the cornea. These solutions work well for ultrashort pulsed laser incision cutting, because there is no need to allow material to be ejected from the target surfaces. A limitation of applanating devices is that direct ablation cannot be done at the same time. A means of placing tightly focused ultrashort pulsed laser pulses at targeted surface(s), with the targeted surface(s) unobstructed, is needed to enable the ablation modality of the present invention.
Bille et al teach the use of laser-produced bubbles on the surface of the cornea to serve as tracking features for a laser-based tracking system in U.S. Pat. No. 4,848,340. One limitation of this invention is the low contrast that a surface ablation feature on the cornea presents. A second limitation is the undesirability of introducing additional injuries or lesions to the surface of the cornea.
In U.S. Pat. No. 6,579,282, Bille et al teach the placement of bubbles created inside the corneal stroma by laser photoablation, with the bubbles serving as guide features for image-based eye tracking systems. The bubble features for eye tracking are created rapidly by a scanning laser, and may be created by an ultrashort pulsed laser. A limitation of this approach is the low contrast bubbles may present to eye tracking systems. A second limitation is that laser-generated bubbles in stroma dissolve and are resorbed in the corneal tissue over time. A third limitation is the well-known phenomenon from ultrashort pulsed laser corneal surgery in which bubbles created by laser vaporization in the corneal stroma move along lamellar planes in unpredictable ways.
3. Objects and Advantages
Accordingly, in addition to the objects and advantages of the apparatus and methods described in my above patent, several objects and advantages of the present invention are:                a) to provide a means of inducing a refractive change in the human eye by direct removal of corneal tissue with ultrashort pulsed laser ablation;        b) to provide a means for ablating stromal tissue on the posterior surface of an exposed corneal flap with an ultrashort pulsed laser;        c) to provide a means of allowing the use of high average power and high pulse energy ultrashort pulsed laser beams to ablate ocular tissue that exceed safe limits when used on an exposed corneal stromal bed as in LASIK or related treatments;        d) to provide a means of producing ablation profiles of ocular tissue of high spatial modulation;        e) to provide a means of ablating and thereby removing tissue with small lateral dimensions as in an adhesion or tag of corneal tissue;        f) to provide a means of removing sections of corneal tissue of thickness smaller or more friable than can be safely removed and cut by incisional means;        g) to provide a means of ablating ocular tissue with high pulse rate ultrashort pulsed lasers that allows for relaxed positional tolerances between target tissue and ablating beam;        h) to provide a means of ablating ocular tissue with high pulse rate ultrashort pulsed lasers using an imaging eye tracking system to compensate for involuntary motion of the eye;        i) to provide a means of incising or ablating ocular tissue with ultrashort pulsed lasers without the need for an applanating optic in contact with the cornea;        j) to provide a means of creating high contrast fiduciary marks in cornea for use with an image-based eye tracking system;        k) to provide a means of creating fiduciary mark features in human cornea with ultrashort pulsed laser incisions having sufficiently small width so as to avoid interfering with visual acuity of the patient;        l) to provide a means of creating fiduciary mark features in human cornea with ultrashort pulsed laser incisions which can be selectively impregnated with water-based dyes;
One advantage of the present invention is that a single laser platform may be used to perform corneal refractive surgery, eliminating the need for two separate and expensive laser systems. A further advantage is that the invention may be used to create incisions and to directly ablate tissue to create a refractive effect, allowing a single instrument to perform many of the procedures presently performed by various laser and non-laser keratome instruments. A further advantage is that the invention requires less direct contact with the eye relative to other ultrashort laser keratomes, offering the possibility of vision correction procedures that are less invasive than at present. In particular, some incisional procedures may be performed without the need for an applanating optic in contact with the cornea. Such minimal touch surgical procedures reduce the risk of infection, allow for greater patient comfort, and are associated with lower complication rates.
Further objects and advantages will become apparent from a consideration of the drawings and ensuing description.

Laser apparatus and method for refractive surgery


A tripod with accessories, including a tripod having three pivotal legs that when extended finds support upon the ground, and when retracted, incorporates a pair of lateral wheels that allow for the tripod to be moved as a dolly, the wheels are provided upon two of the tripod legs, and the third or back leg has an equipment platform, upon which equipment may be applied, to facilitate their movement when the tripod is collapsed, titled forwardly, to cart the equipment around with the tripod to other locations within in a plant or upon the ground.

Tripods have been available for many, many years. They come in all shapes and sizes, some very small to hold cameras, or small telescopes, others are larger for holding surveying instruments, to elevate them to an eye-level position. Tripods usually have three extendable legs, that can be shifted into greater length or leveled, in order to provide an upper stand for the mounting of the instrument when employed. Such instruments may include theodolites, transits, laser trackers, and many other instruments known in the art. Usually there is also a center post that can be elevated, to bring the platform of the transit up to a reasonable height during usage.
In close tolerance industrial surveys, various survey instruments such as laser trackers, scanners, laser projectors, and portable CMMS are mounted onto the top of the industrial survey instrument stand. Generally, these are oversized camera tripods. Popular models are of the portable tripod type design. There are a good number of companies that have been manufacturing and marketing such stands for many years.
As known, and to this date, the only tripod that has any movable or shiftable features, includes a tripod with very small casters at the bottom of each leg. These types of casters are used for rolling around a room and not for traveling any great distance, particularly when used in a large plant, or even during outdoor applications, such as in conjunction with surveying equipment.
Examples of various types of tripods can be seen in select U.S. patents.
Various types of tripods and stands have long been available in the art. Some of the more current ones can be seen, for example, in the U.S. Pat. No. 8,836,508, upon an apparatus and method for securing a portable electronic device. A tripod that includes a case for holding equipment, can be seen in U.S. Pat. No. 8,702,895, disclosing a portable archery target support.
Other early patents relating to tripods can be seen in U.S. Pat. No. 366,833, U.S. Pat. No. 2,828,097, U.S. Pat. No. 2,899,204, a tripod like table with fastening means as shown in U.S. Pat. No. 3,137,522; a tripod supported grill as disclose in U.S. Pat. No. 4,120,280; U.S. Pat. No. 5,029,765, showing a camera support stand; a target holder having adjustable legs as can be seen in U.S. Pat. No. 5,145,133; and a tripod like frame support as shown in U.S. Pat. No. 7,172,512.

Combination portable industrial/survey instrument stand with conveyance capacities


A new approach is proposed to support autonomous similar and adjacent attack identification. First, an incident is created for a detected suspicious electronic message-borne attack at one user account with one tenant on an electronic communication platform. A plurality of insight events for similar or adjacent attacks are then generated automatically based on the detected attack and inserted into an insights queue. For each of the insight events in the insights queue, a search is conducted in a repository to identify a set of un-remediated attacks against user accounts of the same or different tenants on the electronic communication platform, wherein the set of un-remediated attacks are similar or adjacent to the detected attack. Insights on the identified un-remediated attacks against the user accounts in the same or different tenants that are similar or adjacent to the detected attack are automatically generated for an administrator and are remediated accordingly.

The massive expansion of Internet usage that has occurred since the mid-1990's has spawned a corresponding increase in cyber attacks, which may be broadly defined as any attack that involves an electronic device and a network (including particularly the Internet). Many of the cyber attacks are electronic message-borne, wherein the attacks are carried out via malicious electronic messages that include but are not limited to emails, text messages, instant messages, online chats on a social media platform, voice messages or mails that are automatically converted to be in an electronic text format, or other forms of electronic communications. These malicious electronic messages evade security check points (e.g., firewalls at gateways) of an internal network of an entity/organization and land in inboxes of users' account at the entity. The electronic communication system at the entity need to respond quickly and accurately to the electronic message-borne attacks to prevent increase in damage and to limit the spread of the attacks via forensics (after the fact) analysis and incident response.
Forensics and incident response to the electronic message-borne attacks often relies on users' reporting of suspicious electronic messages for an administrator of the entity's electronic communication system to be aware of the new electronic message-borne attacks/threats to the users in the organization. One of the challenges with the reporting of suspicious electronic messages is that the malicious parties that initiated those electronic message-borne attacks often tend to vary the contents of their attacks to obfuscate detection by forensics analysis. As a result, when trying to remediate an incident of an electronic message-borne attack, the administrator may miss the scope of the attack within the entity's network, which may lead to untold monetary and legal consequences for the entity. Due to the evolving nature of the vectors/variables/varying factors of the electronic message-borne attack, it is critical for the administrators to fully comprehend the extent of an attack inside their entities and remediate threats in a timely manner.
The foregoing examples of the related art and limitations related therewith are intended to be illustrative and not exclusive. Other limitations of the related art will become apparent upon a reading of the specification and a study of the drawings.

Method and apparatus for autonomous identification of similar and adjacent attacks based on detected attacks


Multiple drives are coupled together to cause rotation about a single axis by an arrangement in which two moveable electrode plates flank a fixed electrode plate such that the opposite direction rotations of the two moveable electrode plates are combined. To this end, at least one arm from at least one of the moveable electrode plates is connected to at least one arm of a moveable electrode plate on the opposite side of the fixed electrode plate, e.g., by a spring. The electrode plates may have comb projections. A post may be coupled at one of its ends to the top of one of the moveable electrode plates, and the post's other end is coupled to a plate, e.g., a mirror or other structure to be moved.

Electrostatic actuators for MEMS devices are well know. Such actuators typically include two plates that are attracted to each other when they are biased with a voltage difference. Comb drives are modified versions of such plate electrostatic actuators that use plates from which overlapping protrusions know as combs extend. See for example, U.S. Pat. No. 6,872,947. Torsional electrostatic actuators typically have one plate fixed and one that is free to rotate about an axis, often by virtue of being connected to a softer element, e.g., a spring of some type, at the axis point.


A dot forming element array is driven during each main scan to enable successive formation in the main scanning direction of sets of N dots formed substantially along a straight line in a sub-scanning direction at intermittent timing which enables the dot forming element array conducting a scan in the main scanning direction to form a prescribed number of sets of N dots and thereafter disables it from forming dots for (s-1) dot positions (s being an integer greater than 1). An adjustment for shifting the recording positions of the sets of N of dots in the main scanning direction by an integral multiple of the dot pitch w from a prescribed basic position is effected in at least some main scans to enable servicing of multiple dot positions in a desired recording region on the recording medium.

1. Field of the Invention
This invention relates to a method and an apparatus which effect recording on the surface of a recording medium by a recording head which scans the surface of the recording medium in a main scanning direction and a sub-scanning direction.
2. Description of the Related Art
Recording apparatuses which effect recording while causing a recording head to scan in a main scanning direction and a sub-scanning include, for example, the serial scan printer and the drum scan printer. As taught by U.S. Pat. No. 4,198,642 and Japanese Patent Laying-Open Gazette No. 53-2040, for example, a technique called the "interlace scheme" has been developed for improving the image (print) quality of printers of this type, particularly those that employ ink jet nozzles.
FIG. 22 is a diagram for explaining an example of the interlace scheme. In this specification, the following parameters are used to define printing scheme.
N: Number of nozzles PA1 k: Nozzle pitch PA1 s: Number of scan repeats PA1 D: Nozzle density nozzle/inch! PA1 L: Sub-scanning pitch inch! PA1 w: Dot pitch inch!
The number of nozzles N is the number of nozzles used to form dots. In the example of FIG. 22, N=3. The nozzle pitch k is the interval between the centers of the recording head nozzles expressed in units of the recorded image pitch (dot pitch w). In the example of FIG. 22, k=2. The number of scan repeats s is the number of main scans in which all dot positions on a main scanning line are serviced. In the example of FIG. 22, s=1, i.e., all dot positions on a main scanning line are serviced in a single main scan. When s is 2 or greater, the dots are formed intermittently in the main scanning direction. This will be explained in detail later. The nozzle density D (nozzle/inch) is the number of nozzles per inch in the nozzle array of the recording head. The sub-scanning pitch L (inch) is the distance moved in 1 sub-scan. The dot pitch w (inch) is the pitch of the dots in the recorded image. In general, it holds that w=1/(D.multidot.k), k=1/(D.multidot.w).
The circles containing two-digit numerals in FIG. 22 indicate dot recording positions. As indicated in the legend, the numeral on the left in each circle indicates the nozzle number and the numeral on the right indicates the recording order (the number of the main scan in which it was recorded).
The interlace scheme shown in FIG. 22 is characterized by the configuration of the nozzle array of the recording head and the sub-scanning method. Specifically, in the interlace scheme, the nozzle pitch k indicating the interval between the centers of adjacent nozzles is defined as an integer not smaller than 2, while the number of nozzles N and the nozzle pitch k are selected as integers which are relatively prime. Further, sub-scanning pitch L is set to N/(D.multidot.k) (=N.multidot.w).
The interlace scheme has the advantage of enabling nonuniformity of nozzle pitch, ink jetting characteristic and the like to be spread out over the recorded image. Because of this, it improves image quality by mitigating the effect of any nonuniformity that may be present in the nozzle pitch, the jetting characteristic and the like.
The shingling scheme, also known as the multiscan scheme, taught for example by Japanese Patent Laying-Open Gazette No. 3-207665 and Japanese Patent Publication Gazette No. 4-19030 is another technique used to improve image quality in color ink jet printers.
FIG. 23 is a diagram for explaining an example of the shingling scheme. In the shingling scheme, 8 nozzles are divided into 2 nozzle sets. The first nozzle set is made up of 4 nozzles having even nozzle numbers (left numeral in each circle) and the second nozzle set is made up of 4 nozzles having odd nozzle numbers. In each main scan, the nozzle sets are each intermittently driven to form dots in the main scanning direction once every (s) dots. Since s=2 in the example of FIG. 23, a dot is formed at every second dot position. The timing of the driving of the nozzle sets is controlled so that the each nozzle set forms dots at different positions from the other in the main scanning direction. In other words, as shown in FIG. 23, the recording positions of the nozzles of the first nozzle set (nozzles number 8, 6, 4, 2) and those of the nozzles of the second nozzle set (nozzles number 7, 5, 3, 1) are offset from each other by 1 dot in the main scanning direction. This kind of scanning is conducted multiple times with the nozzle driving times being offset between the nozzle sets during each main scan to form all dots on the main scanning lines.
In the shingling scheme, the dots of each main scanning line are not all recorded by the same nozzle but by multiple nozzles. Even when the nozzle characteristics (pitch, jetting characteristic etc.) are not completely uniform, therefore, enhanced image quality can be obtained because the characteristics of the individual nozzles is prevented from affecting the entire main scanning line.
Securing high image quality with a printer or other recording apparatus requires prevention of image quality degradation by variance (nonuniformity) of the nozzle pitch, the jetting characteristic and the like. Conventionally this has been achieved by use of the aforesaid interlace scheme or shingling scheme.
A simple combination of the interlace scheme and the shingling scheme is problematic because it makes the scanning speed difficult to increase. This is because use of the shingling scheme requires the recording head to be supplied with a drive signal Sdot' (FIG. 23) capable, for example, of distinguishing both the dot positions of the even-numbered nozzles and the dot positions of the odd-numbered nozzles. This means that the recording head has to be supplied with a drive signal Sdot' capable of distinguishing all dot positions in the main scanning direction.
When the main scanning speed of the recording head (the carriage speed) is increased, the drive frequency of the drive signal Sdot' has to be increased in proportion. Moreover, the print data sent to the printer from a personal computer or other print data generating device have to be sent to the printer as data corresponding to the individual dot positions. Up to now, therefore, the recording head main scanning speed has sometimes been limited by the nozzle drive frequency and/or the print data supply speed.

Dot recording method and apparatus therefor


AV stream files and original management files are initially recorded in a first data recordable area of an optical disc. After the recordation of the original management files in the first data recordable area, at least one backup management file is recorded in a second recordable area of the disc. When associated original file system information is recorded in the first data recordable area after the recordation of the backup management file, backup file system information is recorded in a third data recordable area. All of the first, second, and third data recordable areas are closed after the recordation of the backup file system information.

Optical discs are widely used as a recording medium for recording mass data. Presently, among a wide range of optical discs, a new high-density optical recording medium, such as a Blu-ray Disc (hereinafter referred to as "BD"), is under development for writing and storing high definition video and audio data. Currently, global standard technical specifications of the Blu-ray Disc (BD), which is known to be the next generation technology, are under establishment as a next generation optical recording solution that is able to record and store data significantly surpassing the conventional DVD, along with many other digital apparatuses.
Accordingly, the write-once blu-ray disc (BD-WO) is currently under discussion as the blu-ray disc standard. However, since the Blu-ray Disc (BD-WO) standards are yet to be completed, there have been many difficulties in developing a complete optical recording and reproducing apparatus. More specifically, in order to efficiently reproduce the data recorded on the blu-ray disc (BD-WO), a management file and a file system information for managing the files having data recorded therein are necessary and should be provided by a systematic and standardized method. However, in the current blu-ray disc (BD-WO) standard, since a consolidated standard for the method for recording and reproducing the management file and the file system information has not been completed, there still remain many restrictions in fully developing blu-ray disc (BD)-based optical recording and reproducing apparatuses.

Recording medium and method and apparatus for recording data on the same