The invention relates to a method and a device for modifying in a spatially periodic manner at least in some regions a surface of a substrate (24), said surface being disposed on a sample plane (P) for which end different regions (211, 221, 231, 232) of the substrate surface are acted upon successively with a spatially periodic illumination pattern of an energy density above a processing threshold of the substrate surface, where the illumination pattern is generated by diffraction of an input beam (10) and superimposition of resulting, diffracted sub-beams (12, 14) by means of a grid interferometer (100), and where, in order to select the substrate surface region to be illuminated in each case (211, 221, 231, 232), the input beam (10) is deviated by means of a beam-deviating unit (16) arranged upstream of the grid interferometer (100).

1. Field of the Invention
The invention relates to a method for modifying in a spatially periodic manner at least in some regions a surface of a substrate, said surface being disposed on a sample plane, for which end different regions of the substrate surface are acted upon successively with a spatially periodic illumination pattern of an energy density above a processing threshold of the substrate surface, wherein the illumination pattern is generated by diffraction of an input beam and superimposition of resulting, diffracted sub-beams by means of a grid interferometer, and wherein, in order to select the substrate surface region to be illuminated in each case, the input beam is deviated by means of a beam-deviating unit arranged upstream of the grid interferometer. The invention relates further to a device for modifying in a spatially periodic manner at least in some regions a surface of a substrate, said surface being disposed on a sample plane, comprising a beam-deviating unit to select a current processing region by controlled deviation of an input beam, and a grid interferometer arranged downstream from the beam-deviating unit, which interferometer bends the input beam and superimposes in the sample plane the resulting, diffracted sub-beams to create a spatially periodic illumination pattern in the current processing region.
2. Description of the Related Art
Methods and devices in the field of the invention are known from DE 10 2006 032 053 A1. Such devices and methods are used in areas such as security technology to equip documents, coins, bank notes, etc. with an anti-counterfeit security feature. When the correct pattern is selected, the structures implanted in the surfaces of films, coins, plastic carriers and other substrates produce defined optical effects, e.g. a reflection that is dependent on wavelength and/or direction.
For the generic method and/or generic device, an input beam, especially a laser beam, is directed through a grid interferometer to create the spatially periodic illumination pattern. For the purposes of this application, a grid interferometer is understood to be a device with at least two optical grids parallel to one another and which are essentially horizontally arranged with respect to an optical axis where an input grid is arranged so as to split an input beam into a plurality of sub-beams by diffraction, and an output grid is arranged so as to reconstitute in a sample plane a selection of the sub-beams created at the input grid or at other intermediate grids. The distance d between two adjacent grids is typically equal to the distance between the grid that is last following the direction of the beam and a sample plane P arranged further downstream with respect to the beam. The periods of the grids are in a specific proportion to one another that determines the orders of the usable sub-beams that interfere with one another and are superimposed in P. The following applies generally to the embodiment of the grid interferometer that is particularly relevant in practice, namely a two-grid interferometer with two grids G1 and G2 with corresponding grid periods p1 and p2: If the sub-beams of order n1 created by way of diffraction at G1 are again diffracted at G2 and the resulting sub-beams of order n2 are made to interfere and superimpose in P, the proportion of the grid periods should be p2/p1=n2/(2*n1). An expert would be familiar with the generalisation extending to grid interferometers with more than two grids. FIG. 1 illustrates the beam path of such a two-grid interferometer with n1=1 and n2=2, i.e. p1=p2. Suitable means of beam selection, e.g. apertures, are provided to select the correct sub-beams; for purposes of clarity they are not represented in FIG. 1.
A major advantage of the grid interferometer is its quality of forming the interference pattern independently of spatial and temporal coherence, wavelength, and incident angle of the input beam. In practice, it will be difficult to completely, i.e. perfectly, satisfy the above conditions regarding distances and grid periods; however, even under realistic conditions in practice, the aforementioned independence of the input beam's parameters remains true, at least to the relevant extent.
If the energy density of the illumination pattern is high enough to overcome a process threshold of the substrate surface, a corresponding permanent structure can be thus implemented within the substrate surface. The concept of process threshold is conceived broadly and encompasses, for example, a destruction threshold (e.g. for laser ablation) as well as energy thresholds for thermal or photochemical reactions.
Such process thresholds are generally relatively high, which means that strong focussing on the substrate surface is usually necessary. The cited category-defining document is therefore especially concerned with forming the input beam such that the energy density on the substrate surface is high enough to overcome the process threshold, yet also that the energy density in the region of the grid interferometer remains sufficiently low to as not to provoke destruction of the grid. The strong focussing ultimately means that the given region of the substrate surface that is illuminated, i.e. the current processing region, is comparatively small.
To create large-scale patterns, the cited document therefore suggests that a beam-deviating unit, such as a mirror scanner that deviates the input beam such that the illumination pattern can be shifted in a larger region of the substrate surface such that a large-scale structure can be successively created the substrate surface.
However, this approach is limited as the size of the region that can be achieved is highly restricted. The position of the focal plane of the input beam, especially its distance from the sample plane, varies with the deviation angle. The focus is on a spherical shell segment around the point of deviation. The image sharpness of the interference pattern, as well as the energy density with which the sample surface is hit, vary accordingly, and thus the processing efficiency varies depending on the diffraction angle.
A method and a device as described above are known from US 2006/0109532 A1, however without a beam-deviating unit. To process larger substrates, the substrates are positioned on a movable platform that is shifted after a sub-field has been processed such that a second field for processing is shifted into position at the place where the interference pattern is created.
U.S. Pat. No. 6,882,477 B1 also discloses a similar device without a beam-deviating unit and with a movable sample platform.
A method and device for laser tempering of polycrystalline semi-conductor layers are known from US 2004/0074881 A1. It relates to using a focussed laser beam to scan a processing surface. To do so, a collimated beam is deviated by a galvanometric mirror scanner wherein an F-Theta lens arranged downstream from the mirror scanner serves to focus the beam on the substrate surface independently of the deviation angle.
It is the task of the present invention to improve a generic method and a generic device such that it is possible to create large-scale patterns.

Method and device for spatially periodic modification of a substrate surface


A circuit (400) is described herein for controlling dimming of a lamp (112), the circuit comprising a switching circuit (422) configured to provide a chopped portion of an input AC power signal, a resettable inverting integrator circuit (426) configured to integrate the chopped portion of the input AC power signal such that a rise time of an output of the resettable inverting integrator circuit is proportional to a positive amplitude of the chopped portion of the input AC power signal and a fall time of the output of the resettable integrator is proportional to a negative amplitude of the chopped portion, such that an energy provided to the lamp based on the output of the resettable inverting integrator circuit is substantially equivalent from cycle-to-cycle of said input AC power signal regardless of a change in amplitude of the input AC power signal from cycle-to-cycle.

1. Technical Field
The aspects of the embodiments described herein relate to an apparatus and method for correcting flicker situations encountered in the use of dimmer units for lighting controls.
2. Background Art
Lighting controls are prevalent in both home and commercial applications. Some lighting controls are very simple, e.g., on/off switches, but others include remote operation and dimming controls, which can be manual or automatic. Regardless of how the dimming controls are operated, it is important that dimming controls operate properly. As those of skill in the art can appreciate, while conventional dimming technology has been available for a very long time, there are still some problems with existing technologies.
One such problem in dimming controls is referred to as "flicker." Flicker is the condition in which the power or voltage that is transferred to the lamp is inconsistent over different cycles of 60 Hz or 50 Hz AC input voltage. This causes the lamp to become brighter and/or dimmer from cycle-to-cycle, ½ cycle to ½ cycle, or over multiple cycles, thereby exhibiting a flicker effect. While the human eye can average some discrepancies in different amounts of brightness over different cycles, due to, in part, its response time to light impulses, when the difference in amount of brightness due to changes in the control voltage reaches a certain threshold, the effect becomes significant. This can cause a reaction to those subjected to the flicker ranging from annoyance to headaches and other maladies. For example, photosensitive epilepsy (PSE) is a form of epilepsy in which seizures are triggered by visual stimuli that form patterns in time or space, such as flashing lights, bold, regular patterns, or regularly moving patterns.
As known by those of skill in the art, dimming controls conventionally "throttle" or control the amount of voltage that is applied to the lamp (for purposes of this discussion, the "lamp" can be incandescent, fluorescent, or a light emitting diode (LED)). This throttling is based on time; i.e., a 50% reduction in brightness would translate to cutting off the voltage transferred to the lamp about half-way through each of the positive and negative half cycles. This typically would occur when the AC voltage reaches either its positive maximum or its negative maximum. The amount of energy delivered to the lamp is dependent upon the voltage-time product provided in the waveform or voltage applied to the lamp.
FIG. 1 illustrates a conventional wall mounted dimming control apparatus (dimmer) 100 for use in housing conventional dimming control circuitry 108 (which is discussed in greater detail in regard to FIG. 2). In FIG. 1, conventional house AC power (Hot_Power) 102 and neutral 104 are input to wall-mounted box 106, which houses dimming control circuitry 108. The output of wall-mounted box 106 is DIM_Hot output 110, which is connected to a first connector of lamp 112, and a second connector of lamp 112 is connected to neutral 104, which is also received and used by dimming control circuitry 108. DIM_Hot output 110 is a controlled version of Hot_Power 102 that dims lamp 112. Control of DIM_Hot output 110 occurs through action of switch 114, which, as those of skill in the art can appreciate, is generally a rotatable potentiometer that provides a variable voltage to additional circuitry (discussed in FIG. 2) that assists in generating DIM_Hot output 110.
FIG. 2 illustrates conventional dimming control circuitry 108 in greater detail. Dimming control circuitry 108 includes FET drive circuitry 210, which resides on DIM switch board 216, switch 114, first opto-isolator 212, and second opto-isolator 214. Dimming control circuitry 108 further includes a bi-directional switch that includes first and second MOSFETs (transistors Q1, Q2) 206, 208, which receives, as respective input drive signals, FET_A_DRV—1 input signal 202 and FET_B_DRV—1 input signal 204, which are generated by operation of switch 114, FET drive circuitry 210, and first and second opto-isolators 212, 214. FET drive circuitry 210 is a conventional FET drive generation circuit for the control of transistors Q1 and Q2 206, 208 known to those of skill in the art, and therefore a detailed explanation of such is not necessary in fulfillment of the dual purposes of clarity and brevity. FET_A_DRV—1 input signal 202 controls transistor Q1 206 through first opto-isolator 212, which isolates the high voltage transistor Q1 206 from certain portions of the circuitry on FET drive circuitry 210, and FET_B_DRV—1 input signal 204 controls transistor Q2 208 in a similar manner (i.e., isolation via second opto-isolator 214), both of which act together to control the flow of 120 VAC, or Hot_Power 102 in the form of DIM_Hot output 110 to lamp 112. FET_A_DRV—1 input signal 202 and FET_B_DRV—1 input signal 204 are generated by other circuitry which is not shown or discussed in fulfillment of the dual purposes of clarity and brevity. DIM switch board 216 can contain the circuitry that not only creates FET_A_DRV—1 input signal 202 and FET_B_DRV—1 input signal 204, but also switch 114, and other circuitry as well.
FET_A_DRV—1 input signal 202 and FET_B_DRV—1 input signal 204 control dimming of lamp 112 in the following manner. FET_A_DRV—1 input signal 202 controls transistor Q1 206 on for the positive and negative going portions of Hot_Power 102, and FET_B_DRV—1 controls Q2 208 on for the positive and negative portions of Hot_Power 102. When FET_A_DRV—1 input signal 202 is active, it turns on transistor Q1 206, allowing it to act as switch. Similarly, when FET_B_DRV—1 204 is active, it turns on Q2 208 allowing it to also act as a switch. For positive portions of Hot_Power 102, the positive current can flow through transistor Q1 206 from its drain to its source, and through Q2 208 from its source to drain, and then out of the Dim_Hot output 110. FET_A_DRV—1 input signal 202 and FET_B_DRV—1 input signal 204 will be active for some portion of the positive and negative voltage cycle of Hot_Power 102, to control the dimming of lamp 112. For negative portions of Hot_Power 102, the negative current flows into Dim_Hot 110, through transistor Q2 208 from its drain to source, and then through Q1 206 from its source to drain. Typically, FET_A_DRV—1 input signal 202 and FET_B_DRV—1 input signal 204 are symmetrical, and gated in time to cause the correct dimming of lamp 112 as known by those of skill in the art.
FIG. 3 illustrates normal dimming control power voltage signal DIM_Hot output 110 when there is no over- or under-shoot situation in the input 120 VAC power waveform (Hot_Power 102) and a flicker-causing dimming control power voltage signal when there is both an over- and under-shoot situation in DIM_Hot output 110. In a first example, Hot_Power 102, which is input to the bi-directional switch shown in FIGS. 1 and 2, is controlled such that only 50% brightness is desired, so that in conventional FET drive circuitry 210, only half of the positive and half of the negative going portions of Hot_Power 102 is allowed to conduct to lamp 112, and the resulting waveform is DIM_Hot output 110a. It can be readily appreciated that about half of each of the positive and negative portions of each 120 VAC cycle is now output to lamp 112. Decreasing the amount of energy that reaches lamp 112 reduces the brightness emitted therefrom. Because there is little or no variation in input Hot_Power 102 and thus output DIM_Hot output 110a, this results in a substantially if not completely non-flicker situation because Hot_Power 102 and DIM_Hot output 110 are substantially uniform and the energy sent to lamp 112 has been reduced proportional to the dimming control signal.
However, in the second example of DIM_Hot output 110b, there is an over-voltage condition, caused by an over-voltage in Hot_Power 102, shown as waveform peak 302. DIM_Hot overshoot 110b will reach the same overshoot level (302) above the normal peak voltage of Hot_Power 102, occurring at about halfway through the positive cycle of the AC power waveform. Consequently, the amount of energy sent to lamp 112 is greater than that which is normally sent. The energy that is transferred during each positive ½ cycle of DIM_Hot output 110a is represented by and shown as first volt-sec product 306; note that second volt-sec product 308 is larger than volt-sec product 306 due to the increase in amplitude of DIM_Hot output 110b at the portion that has been identified as over-volt condition 302, and thus an increase in brightness will result. In under-volt condition 304, which represents an under-voltage condition, third volt-sec product 310 is less than first volt-sec product 306, and a decrease in brightness will result. Both the increase in brightness and decrease in brightness cause flicker.
Another approach to dimming controls is shown in U.S. Pat. No. 7,259,524 to Hausman, et al (the '524 Patent). In the '524 Patent, an apparatus and methods for regulating delivery of electrical energy to a lighting load are described. An electrical waveform is received from a source of electrical energy. An integration value is then generated based on a square of an amplitude of the received waveform. Electrical energy is delivered to the load until the integration value exceeds a threshold value. Thereafter, the delivery of electrical energy to the load is discontinued. As can be appreciated by those of skill in the art, and as can be seen from the '524 Patent, Hausman describes a dimming control system that is fairly complicated—referring just to FIG. 1, it can be seen that there are many circuit devices and signal processing steps involved to control the load on the lamp. That is, a microcontroller, comparator, pulse waveform generator, sawtooth generator and other devices are needed to accomplish the dimming function. Furthermore, the number of amplifiers used to accomplish the dimming function as outlined in FIGS. 8A-8E is about a dozen, and further includes at least two integrated circuits. As those of skill in the art can appreciate, this type of cumbersome approach can lead to premature failure because of the significant number of active components used, as well as required additional power.
Accordingly, it would be desirable to provide methods, modes and systems for improving dimming control circuitry to reduce or substantially eliminate flicker situations.

Flicker compensation in lighting devices


Articles comprising a substrate, preferably a retroreflective sheeting, having a coating of a pressure-sensitive adhesive composition, and articles wherein the adhesive adheres the substrate to a highly monomericly plasticized PVC component, preferably a PVC coated fabric. The adhesive comprises a crosslinked copolymer of a first monofunctional acrylate ester of a non-tertiary alcohol having as a homopolymer a glass transition temperature of less than -25.degree. C., a nitrogen containing moderately basic monomer copolymerizable therewith selected from the group consisting of N,N-dialkyl substituted amides, an optional copolymerizable acidic monomer, an optional second monofunctional acrylate ester of a non-tertiary alcohol having as a homopolymer a glass transition temperature -25.degree. C. or greater, and a crosslinking agent. A method of bonding a highly monomericly plasticized PVC component to a substrate, preferably a retroreflective sheeting, using the adhesive.

1. Field of the Invention
The present invention relates generally to signage articles such as retroreflective and non-retroreflective articles. More particularly, the invention relates to pressure-sensitive adhesives which allow excellent adhesion of retroreflective and non-retroreflective base substrates to surfaces such as highly monomericly plasticized polyvinyl chloride coated fabric, as may frequently be used in tarpaulins.
2. Related Art
In the article "Truck Cover Market Report", Data Textile, May 1991, distinction is made between tarpaulins and truck covers. A truck cover is defined as a fitted cover or a cover specifically designed for use on a flat bed, open top, dump truck or trailer, and differs strictly from a tarpaulin per se, since tarpaulins are not usually fitted for any particular use. For the purpose of the present invention, the terms are interchangeable.
As discussed in Patent Cooperation Treaty (PCT) application no. WO 93/10985, published Jun. 10, 1993, tarpaulins usually consist of a fabric coated with a plastic material. The fabric, although not required in all instances, is usually a woven polyester or nylon, which may have a weft insertion. The plastic material is typically chosen to be tough and flexible, and thus plasticized polyvinyl chloride (PVC), polyamides (such as nylon and aramid), and polyprenes (such as chloroprene rubber) are commonly employed. Tarpaulins are used for many cover purposes, e.g., within the building industry, and in particular for covering trucks. They are also used for making larger tents, e.g., for use in temporary military quarters and refugee camps as well as for public events.
As further stated in the above-mentioned PCT application, it is common practice to print logos, company names, slogans, instructions and other decorations on truck tarpaulins, for informative and for advertising purposes. Reflecting decorations are particularly advantageous, making the trucks visible at night. Often these decorations or adherends are applied outdoors to the truck canvases. Thus, suitable PSAs preferably are capable of application over a broad range of temperatures.
One solution to the problem is described in the above-mentioned PCT application, which describes a tarpaulin comprising a fabric coated with a plastic material, preferably PVC, polyamide, or polyprene, provided with a decoration of a reflecting material by anchoring (with an overlaying transparent flexible film) a reflecting sheet to a piece of intermediate tarpaulin cloth, whose coating is of the same type as (or is compatible with) that of the tarpaulin, by high frequency welding or heat application, and then applying the piece of intermediate tarpaulin cloth provided with reflecting sheet and overlaying transparent flexible film, optionally formed in the desired shape, to the tarpaulin by hot air fusion.
PVC coated fabrics differ primarily in the type and amount of plasticizer added to the PVC. One commercially available PVC coated fabric has been analyzed to contain up to 42 weight percent of low molecular weight monomeric plasticizer. These low molecular weight monomeric plasticizers tend to migrate to the surface of the PVC coated fabric, and tend to cause problems in adhering materials to the PVC coated fabric with pressure-sensitive adhesives (PSAs).
Acrylic PSAs generally comprise a primary component of acrylate or methacrylate monomer or a combination of such monomers which, when polymerized, have a low glass transition temperature (T.sub.g)and low modulus (i.e. they are rubbery and soft). These soft, tacky low T.sub.g monomers are typically copolymerized with a secondary component consisting of high T.sub.g monomers, usually polar monomers such as acrylic acid, methacrylic acid, itaconic acid, acrylamide, methacrylamide, and mixtures thereof. As described in U.S. Pat. No. Re 24,906 (Ulrich), when such polar monomers are incorporated with a predominance of low T.sub.g monomers, a sufficiently tacky pressure-sensitive adhesive is formed having high cohesive or internal strength. Further increase in internal or cohesive strength (i.e., shear strength), which is often required to resist the severe environmental and chemical conditions found in transportation applications, can be obtained via crosslinking.
One approach to reducing the tendency of monomeric plasticizers from migrating out of highly monomericly plasticized PVC coated fabric and into the attached PSA is to load the adhesive with plasticizer, thereby reducing the mass transfer gradient for plasticizer migration from the PVC into the adhesive. Such an approach was taken in U.S. Pat. No. 4,946,742 (Landin), which discloses normally tacky and pressure-sensitive adhesives having excellent long-term adhesion to plasticized vinyl surfaces, prepared from a representative blend of dioctyl phthalate plasticizer and a terpolymer of an alkyl acrylate, a nitrogen containing vinyl monomer and a vinyl carboxylic acid. Addition of the plasticizer to the adhesive, however, adds to the cost of the adhesive, and requires an additional process step. Furthermore, if the plasticizer present in the PVC coated fabric is different from the plasticizer present in the adhesive, a driving force still exists for the plasticizer present in the PVC coated fabric to migrate into the adhesive due to the concentration gradient.
Development of a non-plasticized PSA would allow all fabricators to apply cube-corner type and other types of retroreflective sheeting onto monomericly plasticized PVC coated fabrics, thereby reducing or eliminating the need for thermal attachment methods and for plasticized PSAs.
Assignee's published European patent application no. 615 983 A2, published Sep. 1, 1994, describes a PSA having outstanding ability to bond to solid acidic surfaces such as acidic acid-rain resistant automotive paints and PVC, and to remain firmly bonded thereto, comprising (a) about 60 to about 90 parts by weight of at least one monomer selected from the group consisting of monofunctional unsaturated (meth)acrylate esters of non-tertiary alkyl alcohols, and mixtures thereof, the alkyl groups of which comprise from about 4 to about 12 carbon atoms which as homopolymers have glass transition temperatures below about -20.degree. C.; (b) correspondingly, about 40 to about 10 parts by weight of a basic monomer copolymerizable with the monomer of component (a); (c) about 0 to about 3 parts by weight of an acidic monomer copolymerizable with the monomers of components (a) and (b) wherein when the acidic monomer is included, the basic copolymerizable monomer should be present in a molar excess; and (d) about 0.05 to about 1 percent by weight of a crosslinking agent based upon the total weight of (a) plus (b) plus (c). Representative examples of copolymers described therein are copolymers of isooctyl acrylate (low Tg monomer), acrylic acid and a basic copolymerizable monomer which may be selected from strongly basic, moderately basic, and wealdy basic monomers. Although this work is impressive, there was not disclosed or suggested the use of the PSA compositions therein disclosed in binding a variety of materials, such as used in reflective and non-reflective signage articles, to highly monomericly plasticized PVC surfaces.
PCT application WO 94/19711, published Sep. 1, 1994, describes a retroreflective structure in which an array of free-standing retroreflective prisms is formed on a substrate for application of the structure to pre-existing substrates formed of compatible fabrics, such as tarpaulins. The structure employs a non-pressure-sensitive adhesive which requires time to cure, such as a one component moisture-curable polyurethane adhesive, to adhere the free-standing prisms to the substrate, and thus the structure requires preassembly.
It would be advantageous if pressure-sensitive adhesives lacking plasticizer could be used to adhere retroreflective and non-retroreflective sheeting to highly monomericly plasticized PVC surfaces.

Articles incorporating pressure-sensitive adhesives having improved adhesion to plasticized polyvinyl chloride

Minnesota Mining & Manufacturing Company


Integrated circuits and methods of producing the same are provided. In an exemplary embodiment, an integrated circuit includes a memory cell, wherein the memory cell includes a transistor having a source and a drain, a first resistive unit in electrical communication with the source, and a second resistive unit in electrical communication with the drain. The first resistive unit includes a first bottom electrode, a first top electrode, and a first resistive element positioned between the first bottom electrode and the first top electrode. The second resistive unit includes a second bottom electrode, a second top electrode, and a second resistive element positioned between the second bottom electrode and the second top electrode.

Non-volatile memory cells retain their stored data, even when the power supply is removed. Therefore, non-volatile memory cells are desirable for devices that may be turned on and off during normal use. A resistive memory cell is a structure that includes a resistive element positioned between two electrodes, where the resistance of the resistive element is variable. The resistance of the resistive element can be switched between a high resistance state and a low resistance state, where conductive "filaments" are presumed to form within the resistive element in the low resistive state, and the conductive "filaments" are ruptured or broken in the high resistive state. The "filaments" are presumed to form from a dielectric breakdown where atoms are oxidized in the filament such that the resistance is reduced, so the "filaments" are presumed to be atomic level structures resulting from a local chemical change. A set voltage applied to the electrodes can form the conductive "filaments" so the resistive element is set into the low resistive state. A different reset voltage can be applied to the electrodes to rupture the conductive "filaments," so the resistive element is reset into the high resistive state. This process can be performed repeatedly. The memory cell is read by measuring the resistance of the resistive unit.
A cell window measures the change in resistance in the memory cell between the high and low resistive states. More particularly, the cell window is ten times the resistance in the high resistance state divided by the resistance in the low resistance state. The larger the cell window, the easier it is to read the memory cell. Larger cell windows also provide more reliable reading operations. Known resistive memory units typically include a transistor and one resistive memory unit, and the cell window is about 10. Devices and methods of producing resistive memory cells with larger cell windows are desirable to increase the ease of use and reliability of the integrated circuits.
Accordingly, it is desirable to provide integrated circuits and methods of producing the same with resistive memory cells that have larger cell windows, such as cell windows of about 15 or more. In addition, it is desirable to provide integrated circuits with resistive memory cells having larger cell windows without increasing the footprint or area required for the resistive memory cell, and methods for producing the same. Furthermore, other desirable features and characteristics of the present embodiments will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and this background.

Integrated circuits with resistive non-volatile memory cells and methods for producing the same


An automatic darkening filter assembly for a welding protector and a welding protector that includes the automatic darkening filter assembly. The automatic darkening filter assembly has a housing that forms an opening in which a switchable light filter is arranged. The switchable light filter is retained by a first and a second resilient gasket that are arranged on opposite sides of the switchable light filter and which each extend circumferentially adjacent a periphery of the switchable light filter. The invention helps maximizing the robustness of the welding protector and facilitates assembly.

Automatic darkening filters commonly have a switchable filter that automatically changes from a light-transmission-state (or light-state) to a dark-transmission-state (or dark-state) in response to incident light. The switching is generally achieved through use of a photodetector that is located on, or as part of, personal protective equipment. The photodetector recognizes the presence of the incident light-to-be-filtered, and an electronic module generates a control voltage that, when applied to the switchable filter, causes the filter to change from the light-state to the dark-state.
Automatic light filters have been designed which contain liquid-crystal cells located between polarizing films. U.S. Pat. No. 4,240,709 to Hornell describes a switchable filter that has a single-twisted, nematic, liquid-crystal cell sandwiched between a pair of mutually crossed polarizers. The liquid-crystal cells are optically-transparent glass substrates that include transparent electrode and alignment layers. The liquid-crystal molecules orientate themselves in a particular direction when a voltage is applied across the liquid-crystal cell under the control of an electronic module. Many commercially available products use this kind of switchable filter.
The use of an automatic-darkening filter in a protective shield gives significant ergonomic benefits. Previously welders, for example, had to "nod" their welding shield down when they struck the welding arc to ensure that their eyes were protected from the torch light. Automatic welding filters eliminate this action since the welding shield can be left in position continuously.

Automatic darkening filter assembly for a welding protector and a welding protector


A lens module includes a lens holder, a lens, a set collar, and an adhesive to adhere the set collar to the lens holder. The lens is received in the lens holder, and includes an optical portion, and a locating portion around the optical portion. The set collar holds the lens in the lens holder, and defines a central opening aligned with the lens. The set collar defines three cutouts therein and forms three blocks between the cutouts. The locating lens forms three ribs received in the cutouts and interlocked with the blocks, respectively.

Generally, a lens module includes a lens barrel, lenses received in the lens barrel, and a set collar secured to the lens barrel by an adhesive for holding the lenses in the lens barrel. The lens barrel comprises a stepped inner wall for supporting the lenses thereon. Each lens comprises a central optical portion and a circumferential locating portion with lower and outer surfaces thereof engaging with the stepped inner wall of the lens barrel. The set collar is configured as an annular ring corresponding to the locating portion of the uppermost lens and holds the uppermost lens in the lens barrel. The set collar also defines a central opening which is aligned with the optical portions of the lenses when the set collar is placed on the uppermost lens. An outer surface of the annular portion of the set collar abuts closely against the stepped inner wall of the lens barrel to isolate the lenses from an exterior of the lens barrel. The set collar forms an annular flange surrounding a central opening defined in the set collar. A space defined between the flange and the lens barrel is filled with the adhesive to fix the set collar to the lens barrel, and thus the lenses are held in the lens barrel.
In the case mentioned above, the lenses cannot be adjusted relative to the lens barrel, once the set collar is placed into the lens barrel. Therefore, before the set collar is placed into the lens barrel, the lenses must already be accurately positioned. However, the lenses, especially the uppermost lens, are prone to shifting during assembly of the set collar into the lens barrel. This shifting of the lenses cannot be adjusted unless the set collar is removed from the lens barrel. In addition, because the outer surface of the annular portion of the set collar abuts closely against the stepped inner wall of the lens barrel, the adhesive is merely applied between the set collar and the lens barrel, and the reliability of the lens module is low.
Therefore, what is desired is a lens module with high reliability and precise positioning of lenses therein.


A wheelchair accommodating system and method for providing an ergonomically suitable environment for users having a motor skill limitation and users without a motor skill limitation is provided. The system includes a height adjustment system, a depth adjustment system, and a tilt adjustment system that can be selectively actuated by a user to adjust the position of a platform of the system.

Persons having a motor skill limitation, such as a person confined to a wheelchair, are often unable to make use of systems designed for persons without a motor skill limitation. For example, a conventional desk, table, or other work surface is typically designed for a person who does not have a motor skill limitation. Often, a wheelchair user is unable to use such a system for reasons including, but not limited to, the height of the work surface is not in a position suitable for the wheelchair user, the configuration of the system prevents the user's wheelchair from moving near the work surface, articles positioned on the work surface are beyond the reach of the wheelchair user, etc.
Governments have enacted legislation demonstrating a general desire to provide persons with a disability, including those having a motor skill limitation, access to systems used by non-disabled persons whenever practically possible. Recently, there have been amendments made to such legislation that focus on technology and an overall goal of making electronics and information technology to accessible to disabled persons.
It is generally known to provide a supplemental work surface or workstation that is designed specifically to accommodate a disabled person such as a person confined to a wheelchair. Often such systems require the user to be moved to the work surface and/or provide limited adjustably for the user. Such systems are often must be purchased in addition to systems designed for non-disabled persons. The cost of purchasing multiple systems may be excessive and may discourage parties from adding a system designed specifically for a person having a mobility related disability.
Accordingly, it would be desirable to provide a system, such as a system having a work surface, that is designed to accommodate a user having a motor skill limitation. It would further be advantageous to provide a system incorporating electronics and/or information technology that is designed to accommodate a user having a motor skill limitation. It would also be desirable to provide a system having a work surface that can be brought to the user. It would also be advantageous to provide a system that may be equally suitable for use by a person having a motor skill limitation and by a person without a motor skill limitation. It would further be advantageous to provide a system having a work surface that may be selectively adjusted by a user to position the work surface in an orientation that is ergonomically suitable for the user. It would further be desirable to provide a system of the type disclosed in the present application that includes any one or more of these or other advantageous features.


A method of preparing a ball-shaped synthetic silica glass optical article. The method includes a step of providing a rod-shaped synthetic silica glass having end faces at both sides thereof and having fewer cords per unit volume viewed in a direction perpendicular to a line connecting the end faces relative to the number of cords per unit volume viewed in a direction along the line connecting the end faces. The synthetic silica glass being optically homogeneous in the direction perpendicular to the line connecting the end faces. The method includes the further step of establishing support portions at the end faces of the synthetic silica glass. The rod-shaped synthetic silica glass is thereupon heated while being rotated around an axis connecting the support portions wherein a molten zone is formed. The molten zone of the rod-shaped synthetic silica glass is thereupon deformed by the application of pressure along the axis connecting the support portions whereupon a high purity ball-shaped optical article, having end faces and a side face positioned between the end faces, is formed. The optical article is characterized by a lesser number of cords per unit volume, viewed in a direction perpendicular to a line connecting the end faces relative to the number of cords per unit volume viewed in a direction along the line connecting the end faces. The rod-shaped synthetic silica glass is furthermore optically homogeneous in a direction perpendicular to the line connecting the end faces. The method is concluded by cutting the ball-shaped optical article at the edge support portions.

In the production of semiconductor devices, the lithography technique for forming integrated circuit patterns on semiconductor wafers has strikingly been advanced. In particular, the wavelength of the light rays used in the lithography has increasingly been reduced and changed, for instance, from i-rays emitted from mercury lumps (365 nm) to light rays emitted from excimer lasers such as KrF excimer laser (248 nm) as the degree of integration of LSI's increases. Such reduction in the wavelength of light rays used in the lithography requires the use of silica glass optical parts having high transmittance to ultraviolet rays as optical parts incorporated into the optical system used in the lithography instead of the conventional multicomponent glass optical parts, in particular, the use of chemically purified synthetic silica glass optical parts having highly improved transmittance to ultraviolet rays. Moreover, such optical parts incorporated into these optical systems of high precision should satisfy more strict requirements such as quite excellent transmittance to ultraviolet rays and very high optical homogeneity.
In general, the glass sometimes shows abrupt change in its refractive index appearing in the streak-like or lamellar configuration. Such a heterogeneous structure is generally called "cord" and is distinguished from the homogeneity in the refractive index. In addition, the glass has heterogeneous structures which are accompanied by a change in the refractive index of the glass and such heterogeneous structures are caused due to the heterogeneity of compositions and the heterogeneity in thermal and other conditions during the production thereof. In the optical glass, such a heterogeneous structure including such a cord is a defect which should be removed since the structure would distort the optical path. Furthermore, the optical glass must also satisfy the strict requirements for the homogeneity in the refractive index to an extent depending on the precision required for specific optical systems in order to obtain a highly precise transmitting wave surface.
In the production of optical glass for general use, the homogenization of the refractive index is carried out by compulsorily stirring a melt of molten glass and then gradually cooling the melt under quite strict temperature control in order to satisfy these requirements.
However, it is difficult to heat the silica glass in a crucible up to a high temperature at which the silica glass is in a molten state having a low viscosity because of the nature peculiar thereto. On the contrary, the silica glass has a sufficiently high viscosity even at a high temperature and is insufficient in the flyability. For this reason, it is in fact difficult to obtain silica glass having satisfactory optical homogeneity through a mixing operation such as stirring.
As means for homogenizing such silica glass, for instance, U.S. Pat. No. 2,904,713 discloses a method for homogenizing the whole composition of silica glass which comprises locally heating the silica glass while supporting both ends thereof by a lathe for processing silica glass to partially form a molten zone within the silica glass, twisting, expanding and contracting the molten zone through application of an external force thereto so that the ends approach or are separated from one another while rotating the ends in different manners to move the molten zone over the entire length of the silica glass.
U.S. Pat. No. 3,485,613 discloses a method for performing homogenization of silica glass, called lateral zone melting method, which comprises setting the viscosity of the molten portion of the silica glass, i.e., the molten zone at a level of not more than 1013 P and moving the molten zone over the entire length of the silica glass while twisting the molten zone of the silica glass by rotating both ends of the silica glass in the same direction and at different numbers of revolutions or in different directions.
These techniques for homogenizing silica glass do not intend to eliminate the cord present in silica glass, but U.S. Pat. No. 5,086,352 and Japanese Un-examined Patent Publication (hereunder referred to as "J.P. KOKAI") No. Hei 3-88742 disclose that the cord of silica glass can be removed through these homogenization techniques for silica glass.
Moreover, DEOS No. 42 04 406 A1 discloses a method for eliminating cords of natural and synthetic silica glass in the three directions perpendicular to one another, in which the homogenization of the silica glass while establishing a second rotation axis perpendicular to a first rotation axis for homogenization is carried out by molding a silica glass formed article subjected to a first homogenization in, for instance, an inverted T-shaped mold of graphite having a square cross section to form a rod-like synthetic silica glass having a square cross section and a longitudinal axis in the direction perpendicular to the rotation axis, for the first homogenization treatment, of the rod-like silica glass formed article subjected to the first homogenization, carrying out a second homogenization while using the longitudinal axis as a second rotation axis to completely eliminate cords in the three directions perpendicular to one another in quite high efficiency.
In addition, the method for homogenizing a silica glass material along the two axes perpendicular to one another and for removing cords as disclosed in the foregoing DEOS No. 42 04 406 A1 permits, for the first time, the economical production of a highly homogeneous silica glass formed article free of cord, which may be used in, for instance, the photolithography.
Incidentally, the synthetic silica glass has been used as a silica glass raw material for optical use because of high purity, in particular, a low content of metallic impurities and excellent light transmittance to light rays falling within the ultraviolet region and is prepared according to the direct method or the soot method. For instance, the vapor phase axial deposition method (VAD method) basically comprises the steps of subjecting a volatile silicon compound to the flame hydrolysis, depositing, as a layer, silica fine particles formed during the flame hydrolysis on a substrate which is rotated and then transparentizing the deposit of silica particles. A lamellar heterogeneous structure is thus formed during growing a synthetic silica glass ingot through the transparentizing step and this serves as a lamellar heterogeneous portion in the resulting synthetic silica glass ingot.
Such a lamellar growing stripe in the synthetic silica glass ingot is formed in the form corresponding to the shape of the growing front of the synthetic silica glass and the stripe accordingly form a cord having a curved surface such as approximately a hemispherical surface. A cord having such a curved surface is likewise observed in the synthetic silica glass ingot produced by the direct method and such a cord is considered to be one of the cords present in the synthetic silica glass whose removal is most difficult.
Therefore, if the synthetic silica glass which is once homogenized by, for instance, a simple lateral zone melting method is examined by a strain detector and an interferometer, it would be confirmed that the optical homogeneity thereof in the direction perpendicular to the rotation axis used during the homogenization is lower than that observed in the direction along the rotation axis. This clearly indicates that the effect of the mixing is almost ineffective for the homogeneity in the direction parallel to the rotation axis. Accordingly, it is concluded that the simple lateral zone melting method permits the removal of unidirectional cord and homogenization, but it is very difficult to achieve the removal of cord and homogenization in the three directions perpendicular to one another and that the method is less efficient.
In order to achieve the removal of cord and homogenization in the three directions through homogenization treatment according to such a simple lateral zone melting method, the lateral zone melting procedures should be repeated over a number of times and this requires much expenses. Moreover, if the lateral zone melting procedures are repeated to remove cord, the optical homogeneity of the resulting product in the direction perpendicular to the rotation axis is not always sufficiently high, the silica glass formed article does not show the quality required for optical use and also suffers from a problem of cost.
As seen from these points, the method for homogenizing silica glass comprising natural and synthetic silica glass as disclosed in the foregoing DEOS No. 42 04 406 A1 is an excellent method and permits the production of silica glass free of cords and having high homogeneity in the three directions perpendicular to one another. However, the silica glass formed article as a product prepared by this method shows low transmittance to, in particular, ultraviolet rays falling within the wavelength range of not more than 250 nm and emits fluorescent light rays through irradiation with ultraviolet rays. Therefore, it has been found that the method is insufficient for forming a silica glass article capable of transmitting light emitted from an excimer laser or ultraviolet rays falling within the same wavelength range.
It would be assumed that this problem is caused due to the following fact. The rotation axis for the second homogenization is established by molding synthetic silica glass in a graphite mold according to a high temperature heat-molding method to give a synthetic silica glass molded article, the resulting silica glass article is contaminated by graphite through the contact between the glass and the graphite mold at a high temperature during the molding, and thus the impurities originated from the graphite and present in the silica glass molded article are uniformly distributed throughout the silica glass article during the second homogenization step.
Metallic impurities should be removed from the silica glass as much as possible to produce silica glass articles having good optical stability to the light rays emitted from an excimer laser. For instance, the optical parts of synthetic silica glass must have alkali and alkaline earth metal contents each of which is not more than 50 ppb and transition metal contents each of which is not more than 10 ppb.
In general, the synthetic silica glass formed articles for optical use have been formed according to a high temperature heat-molding method which makes use of a graphite mold. However, when forming a high purity silica glass article capable of transmitting light emitted from an excimer laser or ultraviolet rays falling within the same wavelength range, the formed article is inevitably contaminated through the contact with the graphite mold. For this reason, the application of the high temperature heat-molding method using a graphite mold is limited to the forming steps subsequent to the final homogenization step. If the high temperature heat-molding method using a graphite mold is simply applied to the forming steps subsequent to the final homogenization step, the silica glass formed article is contaminated at only the portions which comes in contact with the graphite mold and accordingly, any influence of such impurities can be eliminated by, if necessary, scraping such contaminated portions. In this case, however, the graphite mold has been produced from graphite having a purity as high as possible to minimize the contamination due to contact between the silica glass and the graphite mold.
Accordingly, the principal object of the present invention is to solve the problem associated with the method for preparing a highly homogeneous silica glass formed article free of cords in the three directions perpendicular to one another, which relates to contamination of the article through the contact with the graphite mold, as disclosed in the foregoing DEOS No. 42 04 406 A1 and to further improve the cord-removing effect and the homogeneity of the resulting formed article.

Method for preparing silica glass article


The present invention discloses a configuration apparatus thereof which can efficiently configure a new home appliance in the home network system comprised of various home appliances. The configuration method of a home network system, comprising of confirming whether a previously-stored logical address is an initial logical address, transmitting a master search packet to the home network system when the logical address previously stored in the storage means is an initial logical address, waiting for a response packet from the home network system, when the response packet is received from the home network system, changing the initial logical address into a predetermined logical address according to reception of the response packet; and when the response packet is not received from the home network system, changing the previously-stored initial logical address into a previously-stored basic logical address.

Home automation for automatically controlling home appliances at home or remotely has almost reached a commercial use stage. At its early stage, the home automation separately controlled each home appliance by using a telephone or infrared rays, and did not connect the home appliances. However, there has been suggested a method for building a network of home appliances by using a communication means, and collectively managing the network by using a controller.
FIG. 1 is a structure view illustrating a general home network system. Referring to FIG. 1, a home network connects various digital home appliances so that a user can always enjoy convenient, safe and economic life services inside or outside the house.
As factors of the advent of the home network, refrigerators or washing machines called white home appliances have been gradually digitalized due to development of digital signal processing techniques, and new information home appliances have been made due to rapid development of home appliance operating system techniques and high speed multimedia communication techniques.
Here, an IT network is built to exchange data between a personal computer and peripheral devices or provide Internet services, and an AV network is built between home appliances using audio or video information. In addition, a living network is built to simply control home appliances, such as home automation or remote meter reading, and may be comprised of a refrigerator, washing machine, microwave oven, electric lamp, gas alarm, air conditioner and telephone.
The home network system includes a master device which is a home appliance for controlling an operation of the other home appliances or monitoring a status thereof, and a slave device which is a home appliance having a function of responding to the request of the master device and a function of notifying a status change according to properties of the home appliances or other factors. Here, the home appliances include home appliances for the living network service such as a washing machine and a refrigerator as well as home appliances for the IT network service and the AV network service.
However, there has never been suggested an apparatus for efficiently configuring a new master device in the home network system, when the master device is firstly configured (connected) or another master device is configured in addition to the existing master device.

Home network system and its configuration system


A high pressure poppet valve having a valve body defining inlet, outlet and vent passages, and with a valve cage in sealed relation within the valve body which defines an internal seat projection having spaced circular seat shoulders. A seal carrier, which may be a pilot pressure responsive piston, supports spaced seal glands each having a seal assembly composed of an elastomeric seal ring which is captured within a gland seal recess by a relatively hard, extrusion resistant seal ring defining a circular sealing corner. A spacer spool is interposed between the seal assemblies and maintains the seal assemblies within the respective gland seal recesses. The spacer spool defines support flanges at each end which cooperate with gland structure to secure the seal assemblies in a manner exposing only the circular seal corners of the extrusion resistant sealing elements for sealing engagement with the spaced circular seat shoulders of the internal seat projection and for securing the circular sealing corners against pressure induced extrusion. The seal carrier element is guided and stabilized during its linear movement within the valve cage.

1. Field of the Invention
This invention relates generally to pilot pressure operated poppet valves and more specifically concerns a three-way, high pressure, pilot pressure operated poppet valve having a guided and stabilized pressure responsive valve piston which supports spaced polymer/elastomer seal assemblies that are designed for high pilot pressure operation in the range of 5,000 psi or greater and high working pressure in the range of 10,000 psi or greater and with seal structure and valve components interrelated to ensure minimum pressure induced extrusion of the seal material and long service life at these high pressure ranges.
2. Description of the Prior Art
While pilot operated poppet valves have been employed for many years, problems have been encountered with poppet valves that operate under high pressure conditions. Particularly, seal damage or detriation occurs by pressure induced extrusion of seal material into gaps between mechanical surfaces. When so extruded, the sealing material can be subject to a condition known as "nibbling" wherein the sealing material is pinched between metal surfaces to the extent that minute sections of the sealing material are cut and broken away. When this condition occurs, especially when it occurs repetitiously, the sealing capablity of the seal can become degraded to the point that valve leakage occurs. It is necessary in this case, to either replace the valve or to replace the damaged sealing elements of the valve to thus restore it to operational condition. The problem of seal nibbling is accenuated under circumstances where the gland of the valve or the valve seat are subject to potential lateral movement such as due to pressure induced vibration or misalignment of valve components during opening and closing movement. For example, if sealing material is pressure extruded into a gap between mechanical valve components and one of the valve components is move laterally, such as by vibration or other pressure induced force, the extruded section of the sealing material can be severly pinched, so that it is either cut away or deformed beyond its elastic limits so that it becomes degraded. Further, high velocity flow of high pressure fluid through a gap of minimal dimension between a valve seat and valve seal can subject the exposed sealing material to high pressure erosion which also degrades the sealing material to the point that its sealing capability can be lost. It is desirable, therefore, to provide a poppet valve mechanism having one or more high pressure seal assemblies, each of which is protected against pressure induced extrusion, nibbling or pressure induced deteriation.
Efforts have been made in the past to design poppet type valves that are responsive to relatively high pressure conditions. U.S. Pat. No. 3,131,722 of Abbott, et al shows a three-way valve that is designed for quick shifting characteristics. The various the seal elements of this valve are in the form of simple O-rings that are located in unsupported relation within seal grooves. A spacer element 22 is employed between the spaced seal glands. The unsupported elastomer seals of Abbott, et al will deteriorate quite readily under the high pressure conditions for which the valve of the present invention is designed. For example, U.S. Pat. No. 3,736,960 of Cohen discloses a snap-acting, fluid amplifing valve including a piston and piston stem arrangement. The spring urged piston has a lower piston element 45 having flat upper and lower elastomer seals for sealing engagement with tapered vent and supply nozzles. These elastomer seals will become damaged quite readily by the influence of high pressure fluid service.
U.S. Pat. No. 3,805,837 of Stampfli discloses a control valve arrangement having a piston that incorporates flap valves 3 and 4 which are spaced by a core 2 in the form of a spool-like member. Only the radially inner portions of the seals of the opposed glands are supported by the spool member 2. Thus, the relatively unsupported elastomer sealing elements will function properly only under average operational pressure conditions. When high working pressures in the range of 10,000 psi are encountered, these unsupported seals will fail quite readily; in fact, they will be readily extruded from their grooves and will be subject to nibbling and other damage. U.S. Pat. No. 3,977,438 of Muchow, et al discloses a pilot valve arrangement having a reset mechanism and having a spool member 35 with a valve head 36 at its lower end and having upper and lower seals that are captured in circular recesses by respective retainer rings or washers. These resilient seals, which may be O-ring type seals, are positioned for engagment with sharp circular seat corners such as shown at 38. These seals, under even nominally high pressure conditions, will be subject to pressure induced erosion, nibbling or other deterioration. The present invention is designed to overcome the disadvantages of the valve seal arrangements that are disclosed in the above identified U.S. Patents and to provide for efficient sealing under extremely high pressure conditions while protecting against pressure induced extrusion, seal nibbling, fluid erosion and other factors that might otherwise result in seal deterioration and resulting valve failure.


A camera has a shutter release button that is depressible to initiate picture-taking, and a self-timer for automatically initiating picture-taking after a predetermined interval of time has elapsed. The self-timer is a flexible resilient diaphragm or thin disk to be manually deformable from a normal state to a deformed state and to have the capability of automatically returning to the normal state from the deformed state after the predetermined interval of time has elapsed. A support in the vicinity of the shutter release button is constructed to receive the self-timer in the deformed state in order to position the self-timer raised from the shutter release button, but to permit the self-timer to automatically return to the normal state after the predetermined interval of time has elapsed in order to depress the shutter release button to initiate picture taking. The self-timer can be removed from the support in order to use the shutter release button without the self-timer or to reuse the self-timer.

The invention relates generally to photography, and more particularly to a camera with a self-timer that is otherwise referred to as a delayed action shutter release or delayed action device.
Film and cameras that are all in one, commonly referred to as disposable single-use or one-time-use cameras, have become well known. The one-time-use camera is a simple point-and-shoot type camera comprising a conventional film cartridge within a cartridge receiving chamber in a main body part, an unexposed film roll prewound from the film cartridge onto a film supply spool within a film supply chamber in the main body part, a film-exposing backframe opening between the cartridge receiving and film supply chambers in the main body part, a fixed-focus taking lens, a film metering mechanism with a rotatably supported metering sprocket that has respective sprocket teeth for engaging the filmstrip at successive film perforations, a manually rotatable film winding thumbwheel coaxially engaged with a film winding spool inside the film cartridge, a single-blade shutter, a manually depressible shutter release button, an exposure counter wheel that has a numerical series of evenly spaced exposure count indicia and is incrementally rotated to successively view the exposure count indicia, an anti-backup pawl that engages the exposure counter wheel to prevent its reverse rotation, a direct see-through viewfinder having front and rear viewfinder lenses, and in some models an electronic flash. A pair of separate front and rear cover parts house the main body part between them to complete the camera. The rear cover part connects to the main body part and/or to the front cover part to make the main body part light-tight. A decorative cardboard outer box or label at least partially covers the front and rear cover parts and has respective openings for the taking lens, etc.
After a picture is taken with the one-time-use camera by manually depressing the shutter release button, the photographer manually rotates the thumbwheel in a film winding direction to similarly rotate the film winding spool inside the film cartridge. This winds an exposed frame of the filmstrip from the backframe opening into the film cartridge and advances an unexposed frame of the filmstrip from the unexposed film roll to the backframe opening. The rewinding movement of the filmstrip the equivalent of slightly more than one frame width rotates the metering sprocket in engagement with the filmstrip to decrement the exposure counter wheel to its next lower-numbered indicia and to pivot a metering lever into engagement with the thumbwheel in order to prevent further manual rotation of the thumbwheel in the film winding direction. Manually depressing the shutter release button to take another picture pivots the metering lever out of engagement with the thumbwheel to permit renewed rotation of the thumbwheel in the film winding direction. When the maximum number of exposures available on the filmstrip have been made and the filmstrip is completely wound into the film cartridge, the one-time-use camera is given to a photofinisher who breaks away a cover door portion of the rear cover part from the main body part and removes the film cartridge with the exposed filmstrip from the cartridge receiving chamber. Then, he removes the exposed filmstrip from the film cartridge to develop the latent images and make prints for the customer.
Typically, one-time-use cameras do not include a self-timer, i.e. a delayed action shutter release, which is manually actuated to automatically initiate picture-taking after a predetermined interval of time has elapsed following the actuation. The predetermined interval of time allows one to become a part of the scene to be photographed after he or she has manually actuated the self-timer.
Prior art U.S. Pat. No. 5,946,514 issued Aug. 31, 1999 discloses a one-time-use camera with a self-timer. The self-timer is built into the camera and includes a number of gears and an escapement, and therefore significantly increases the cost of the camera and is relatively complex.
According to one aspect of the invention, a camera comprising a shutter release button that is depressible to initiate picture-taking, and a self-timer for automatically initiating picture-taking after a predetermined interval of time has elapsed, is characterized in that:
the self-timer is flexible and resilient to be manually deformable from a normal state to a deformed state and to have the capability of automatically returning to the normal state from the deformed state after the predetermined interval of time has elapsed; and
a support in the vicinity of the shutter release button is constructed to receive the self-timer in the deformed state in order to position the self-timer raised from the shutter release button, but to permit the self-timer to automatically return to the normal state after the predetermined interval of time has elapsed in order to depress the shutter release button to initiate picture taking, and to permit removal of the self-timer from the support in order to use the shutter release button without the self-timer or to reuse the self-timer.
According to another aspect of the invention, a method of using a delayed action shutter release with a shutter release button that is manually depressible to initiate picture-taking in order to automatically initiate picture-taking after a predetermined interval of time has elapsed, comprises:
deforming a resilient elastic piece, which serves as the delayed action shutter release, from a normal state to a deformed state to allow the resilient elastic piece to automatically return to the normal state from the deformed state after the predetermined interval of time has elapsed; and
positioning the resilient elastic piece in the deformed state raised slightly from the shutter release button to allow the resilient elastic piece to automatically return to the normal state after the predetermined interval of time has elapsed in order to cause the elastic piece to depress the shutter release button to initiate picture taking.

Camera with self-timer for delayed action shutter release


The present invention provides a glass antenna system with improved reception, a connector of the glass antenna system and a method of producing the glass antenna system. The glass antenna system includes a glass substrate, at least one electroconductive antenna element positioned along a major surface of the substrate, wherein the antenna element provides an impedance which varies over a given frequency band, an impedance matching network secured to the glass substrate in a position such that the impedance matching network is electrically coupled to a portion of the antenna element, and means to electrically interconnect the network to a feedline of an electromagnetic energy transmitting and/or receiving unit. The impedance matching network is used to transform the impedance of the antenna element to a desired impedance. In one particular embodiment of the invention the impedance matching network is part of a connector and is formed along a first major surface of a printed circuit board. The network is electrically connected to the opposing major surface of the board which includes an electroconductive coating. The connector is secure to the glass substrate in a position such that the impedance matching network is electrically coupled to the antenna element. The impedance matching network may be a passive or active impedance matching network. The glass antenna may be incorporated into a laminated windshield wherein glass substrate is a first glass ply and further including a second glass ply secured to the first glass ply, with the antenna element positioned between the plies.

1. Field of the Invention
The present invention relates to an antenna system, and in particular to a glass antenna system for a vehicle windshield having a connector with an integral impedance matching network to optimize the performance of the glass antenna.
2. Technical Considerations
In the past, the traditional motor vehicle antenna for receiving and transmitting electromagnetic signals was a mast or whip-type antenna. Recently, there has been a trend towards incorporating the antenna into the vehicle structure. For example, U.S. Pat. No. 3,987,449 to DeAngelis et al. discloses a wire antenna laminated within a vehicle windshield. U.S. Pat. No. 4,707,700 to Nagy positions an antenna within the roof structure of a vehicle. U.S. Pat. No. 5,416,491 to Nishikawa et al. forms antenna elements on a window using electro-conductive ceramic paints. U.S. Pat. Nos. 4,768,037 and 4,849,766 to Inaba et al. and 5,355,144 to Walton et al. use a transparent electroconductive coating laminated between two glass plies to form the antenna.
In designing an antenna system, attention is given to matching the impedance of the system components, and in particular matching the impedance of the radio, the antenna and the feedline between these two components. This is a critical issue for the performance in FM reception since impedance mismatch results in significant loss of signal. Further complicating the antenna system design is the fact that the impedance of the antenna component of the system may vary substantially over the FM frequency band. This means a simple impedance match, such as a single capacitor, will not address the overall performance issues for FM reception over the entire frequency band.
In a glass antenna, the impedance of the antenna is typically not well matched to the radio and the feedline. One way this issue has been addressed by antenna designers is to design the antenna to have a desired impedance, for example, as disclosed in U.S. Pat. Nos. 5,083,135 and 5,528,314 to Nagy et al. Designing the antenna to a predetermined impedance improves the antenna performance but as discussed above, the impedance generally varies over the FM band based on frequency so that the antenna design may not be optimal over the entire FM frequency band. In addition, designing the antenna to have a predetermined impedance would require each antenna to be designed specifically for the particular type of radio and feedline in the particular antenna system as well as the vehicle into which the windshield is installed.
It would be advantageous to provide a glass antenna system for a vehicle which provides improved performance, in particular for the FM frequencies, without having to redesign the antenna system based on the vehicle and/or types of components used in the system.

Glass antenna system with an impedance matching network


A photographic, digital or video camera (10) includes a housing (12); optionally at least one sensor (18, 20, 25, 30, 36, 39, 40, 50) supported by the housing for detecting a condition of the camera or of a scene to be captured by the camera, or both, and for producing a signal; a viewfinder (38) supported by the housing, the viewfinder including a holographic element 64, 90); a source (68) of light having a wavelength of a color to be displayed in the viewfinder; a collimator (70) for receiving a beam from the source and producing an output beam; an optical system (72-80) to horizontally and vertically raster scan the output beam across the holographic element; and a controller (44) for operating the optical system and modulating the output beam in response to the signal, thereby to cause scanned images to be produced by interaction between the output beam and the holographic element, the scanned images displaying information related to use of the camera.

Viewfinders of varying degrees of sophistication have been used on cameras for many years. The simplest varieties usually provide some sort of frame or reticle which aids the user of the camera during composition of a scene prior to capture of an image. More complex cameras may include mechanical or electronic masking arrangements for changing the field of view to show different aspect ratios to be used for images captured. Electrically actuated analog and digital displays have been provided at edges of the field of view to indicate conditions such as light level, flash readiness, lens setting and the like.
Holographic viewfinder displays have been used in which a holographic element is illuminated in selected areas to produce fixed images. For example, separate fixed images might indicate messages such as film speed or "low light" or "flash needed." Or, separate fixed images might be provided to be illuminated as each frame is exposed. A difficulty with known holographic viewfinder displays is that the images which can be displayed are fixed in time, which severely limits the size, number and/or brightness of images which can be provided in the small field of view of a typical viewfinder. Thus, a desirable improvement would be a viewfinder with a holographic display which can be readily modified to suit the user's desires or updated to reflect changes in photographic conditions.

Camera with scanned display in viewfinder


Embodiments of the present invention may provide an apparatus and a method for transmitting an orthogonal frequency division multiplexing access (OFDMA) symbol in an OFDMA system. A bandwidth limit parameter for generating an OFDMA symbol may be adaptively determined based on the received signal quality of a receiver. An OFDMA symbol may be generated based on the bandwidth limit parameter and transmitted to the receiver. According to embodiments, when the received signal quality of the receiver is bad, the bandwidth limit parameter may be first adjusted before the modulation scheme is changed to have a lower data rate. In such a case, the downlink date rate may be maintained with enhancing the received signal quality of the receiver.

1. Field
Embodiments of the present invention may relate to an apparatus and method for transmitting an orthogonal frequency division multiplexing access (OFDMA) symbol in a radio access system (RAS) of an OFDMA system. More particularly, embodiments of the present invention may relate to an apparatus and method for transmitting an OFDMA symbol based on an adaptive control of a bandwidth limit parameter to enhance a downlink data rate of a WiBro RAS.
2. Background
In the next generation of radio access network such as wireless broadband (WiBro) and world interoperability for microwave access (WiMAX) system, a signal is transmitted in the OFDMA scheme to provide a high data rate service to mobile users. The OFDMA scheme is advantageous since it can cope with problems of terrible frequency selective fading channels due to multi path fading in a radio access system with a high data rate. In the OFDMA scheme, the carriers that are appropriately arranged in the OFDMA signal may be received without interferences due to adjacent carriers. Although the sidebands of the adjacent carriers in the OFDMA signal are overlapped, the carriers are arranged to be orthogonal to each other in the entire OFDMA signal. Thus, they do not interfere with each other.
A guard interval is inserted between two adjacent OFDMA symbols to prevent inter symbol interference (ISI) due to interferences between the adjacent OFDMA symbols, as well as inter carrier interference (ICI) due to crosstalk between the adjacent sub carriers. The guard interval is longer than the maximal delay spread of the channel. Therefore, the symbol duration is a sum of the valid symbol duration, during which the data is actually transmitted, and the guard interval. The receiver removes the guard interval and then demodulates the data for the valid symbol duration. The last signal of the valid symbol duration is duplicated and inserted to the guard interval to maintain the orthogonal characteristics of carriers, which are referred to as cyclic prefix (CP).
The frequency spectrum of the OFDMA signal is a sum of sinc functions, each of which is a frequency function of each sub carrier. If the interval between the adjacent sub carriers is an integer multiple of a reciprocal of the valid symbol duration, then the orthogonal characteristics are maintained. However, the bad roll off characteristics of the sinc function causes the adjacent channel interference to generate. Thus, a band limit filter or a window such as root raised cosine (RRC) is used to remove or decrease out of band spectrum components in order to decrease the adjacent channel interference. Such a window or filter determines a spectrum mask that reduces the ISI and an error vector magnitude (EVM).
Until now, mobile communication systems have been developed to be compliant with specifications, with several reference parameters of the specifications such as a bandwidth limit parameter, being fixed. For example, in the transceiver of WiBro RAS (made by LG-Nortel), the radio frequency (RF) unit has been developed based on the fixed bandwidth limit parameter at the output of the modem.
A symbol is modulated to transmit in binary phase shift keying (BPSK), quadrature phase shift keying (QPSK), 16 quadrature amplitude modulation (QAM) or 64 QAM. Accordingly, the above four modulation schemes are utilized to adjust the data rate to maintain a highest downlink data rate as possible, if the received signal quality of a receiver is not sufficiently good due to noise (e.g., white noise) in the radio air or a long distance between the transmitter and the receiver such as a mobile station or relay. For example, the transmitter transmitting a symbol with 64 QAM lowers the data rate to 16 QAM in response to receiving continual repeat requests from the receiver such as a mobile station to maintain the received signal quality of the receiver at a certain level.
However, if the modulation scheme is changed to have a lower data rate for maintaining the received signal quality of the receiver at a certain level, then it is difficult to maintain transmitting data at a high data rate. The inconvenience of the mobile station users increases since a significant amount of data cannot be transmitted at a high data rate at a time. Further, the bandwidth cannot be efficiently utilized since the number of coded bits per sub carrier decreases.
Therefore, the objective of embodiments according to the present invention is to provide an apparatus and method for transmitting an OFDMA symbol to enable the highest downlink data rate. According to the embodiments, the bandwidth limit parameter may be first adjusted before the modulation scheme is changed to have a lower data rate.

Apparatus and method for transmitting OFDMA symbols


A wafer flow recipe is prepared. Based on this wafer flow recipe, there are estimated and calculated respectively a PCD time from a time point at which a process for coating a resist liquid on a substrate by a coating unit has been terminated to a time point at which a first heating process is started at a first heating unit, a PAD time from a time point at which the first heating process has been terminated at the first heating unit to a time point at which an exposure process is started, and a PED time from a time point at which the exposure has been terminated to a time point at which a second heating process is started at a second heating unit. Then, these estimated times are displayed.

1. Field of the Invention
The present invention relates to a coating and developing apparatus for carrying out coating and developing processes of, for example, a resist liquid to a semiconductor wafer or an LCD substrate (a glass substrate for liquid crystal display).
2. Description of the Related Art
For example, a coating and developing apparatus described in the U.S. Pat. No. 6,507,770 is used in combination with an exposure device in order to execute a series of processes applying a photolithography technique. As shown in FIG. 1, a conventional apparatus comprises a carrier placing section 1A, a process section 1B, and an interface section 1C. The process section 1B comprises a transfer mechanism 12, a liquid processing unit group 14, and a rack unit 13 (13a to 13c). The transfer mechanism 12 comprises, for example, two or more arms at its center. The liquid processing unit group 14 is allocated at the periphery of the transfer mechanism 12, and comprises a coating unit which coats a resist liquid or the like to a wafer W, and a developing unit which carries out a developing process of a resist film exposed in a pattern. The rack unit 13 (13a to 13c) comprises a baking unit which heats the wafer W, a temperature control unit which controls a temperature of the wafer, and a delivery unit which delivers the wafer between the delivery unit 12 and the rack unit 13. The liquid processing unit group 14 and the rack unit 13 (13a to 13c) are stacked in a vertically multi-stepped manner, respectively. An exposure system 1D is provided as an external system connected that is to the coating and developing apparatus via an interface block 1C.
In such a conventional apparatus, the wafer W is taken out from a carrier C of the carrier placing block 1A by a delivery arm 11, and is transferred to the process block 1B via the delivery unit of the rack unit 13a. Then, a predetermined process is applied after the wafer W has been transferred to a predetermined processing unit in accordance with a predetermined sequence. After a resist liquid has been coated, the wafer is transferred to the exposure system ID via the interface block 1C, and a resist film is exposed in a pattern. Then, the wafer W is returned again to the process block 1B after exposure, is subjected to post exposure baking by a baking unit, is cooled by a cooling unit, and is developed by a developing unit.
Recently, with a finer semiconductor device circuit pattern, high processing precision is required for each process and each step of photolithography, and a line width of a circuit pattern is reduced. From such a background, a wafer transfer time between processes is different from another one. If a deviation occurs with a time from a time point of the end of process of the previous step to a time point of starting of process of a next step, the processing of each step is affected. As a result, there is a danger that a deviation occurs with the line with.
Here, a factor causing an adverse effect on the process is not always all the wafer transfer times between processes. Adverse effects on processes are believed to be a PCD time (Post Coating Delay Time), a PAD time (Post Apply Back Delay Time), and a PED time (Post Exposure Delay Time). In the conventional apparatus of the U.S. Pat. No. 6,507,770, prior to carrying out an actual process, time intervals (allowable time intervals) of the PCD time, the PAD time, and PEB Time which does not affect a process such as a small deviation of a circuit line width or the like are obtained in advance, and a wafer transfer schedule is determined so that the PCD time or the like is included in these time intervals (allowable time intervals).
The wafer transfer schedule is determined as follow. First, an operator specifies type and sequence of processing units scheduled for use in a process of manufacturing a customer's specification, and a wafer flow recipe is prepared based on these specified items. Then, this wafer flow recipe is input as data in a process computer. The computer carries out computation based on the wafer flow recipe, and determines the wafer transfer schedule. Further, the computer controls operations of a plurality of transfer mechanisms, respectively, in accordance with the wafer transfer schedule, whereby each wafer W is present at a predetermined time in a predetermined location.
In the meantime, in the prior art of the U.S. Pat. No. 6,507,770, based on the wafer transfer schedule, the PCD time, PAD time, and PED time are obtained by actually processing a product wafer W or supplying a dummy wafer DW. If the obtained PCD time, PAD time, and PED time are improper, the operator recreates the wafer flow recipe, and corrects the number of processing units used or sequence thereof. Then, the product wafer W or dummy wafer DW is actually supplied again in line based on a new wafer transfer schedule, and the PCD time or the like is obtained again.
However, in the prior art, since the product wafer W or the like is actually supplied in line, an excessive amount of work cost or time is required. In addition, if the obtained PCD time or the like is improper, the product wafer W supplied in line becomes unavailable or the dummy wafer W becomes wasteful.
There may be used a technique for restraining a deviation of transfer times of each wafer by making a cycle time control such that all the transfer times of wafers between processes are completely identical to each other. However, according to this technique, although the PCD time and PED time become constant between wafers, it is impossible to identify the time itself such as the PCD time as long as the wafer W is actually supplied, and the PAD time is not constant even if this cycle time control is made. In addition, in this technique, a transfer time is limited in accordance with a process defined as a rate-determining (for example, a developing process), and thus, throughput may be lowered.


Sub-micron objects are manipulated. According to an example embodiment of the present invention, Brownian motion effects are mitigated to facilitate the analysis and/or manipulation of sub-micron objects. In some applications, an electric field is applied to facilitate the manipulation of sub-micron objects in solution, facilitating the analysis of the manipulated objects. In other applications, fluid flow is used to effect the manipulation of sub-micron objects in solution.

The development of electrical, mechanical, biological and other devices has seen dramatic achievements in the implementation of ever-smaller objects and arrangements. In many applications, atomic, molecular or macromolecular arrangements having dimensional characteristics of a relatively small size (e.g., less than 100 nanometers) have seen increased development and implementation. These arrangements are often manufactured, manipulated or otherwise controlled on an atomic scale. Technological areas involving such small-scale objects are often referred to as those areas pertaining to nanotechnology.
One aspect of nanotechnologies that has been challenging relates to the ability to control and/or manipulate sub-micron (e.g., nanoscale) objects. For instance, isolating, orienting, translating or otherwise processing sub-micron objects for analysis and other purposes has been particularly challenging. Where small objects are in fluid solution such as a liquid or gas, Brownian motion of the objects (thermally-driven motion related to collisions of the objects with other molecules in solution) also poses problems to analyzing the objects. At room temperature, Brownian motion is quite large for small objects (mean square displacement per unit time scaling inversely with the diameter).
Previous approaches to manipulating small-scale objects have involved the use of laser tweezers, such as described in A. Ashkin, J. M. Dziedzic, J. E. Bjorkholm, and S. Chu, Observation of a Single-Beam Gradient Force Trap for Dielectric Particles, Opt. Lett. 11, 288 (1986). Magnetic tweezers have also been used to trap and manipulate micron-scale objects. See, e.g., C. Gosse and V. Croquette, "Magnetic tweezers: micromanipulation and force measurement at the molecular level," Biophys. J. 82, 3314 (2002). Other approaches have involved AC dielectrophoresis, which have been used to trap micrometer-scale objects (see, e.g., P. R. C. Gascoyne and J. V. Vykoukal, Dielectrophoretic Concepts for Automated Diagnostic Instruments, Proc. IEEE 92, 22 (2004); J. Voldman, R. A. Braff, M. Toner, M. L. Gray, and M. A. Schmidt, Holding Forces of Single-Particle Dielectrophoretic Traps, Biophys. J. 80, 531 (2001); and T. B. Jones, Electromechanics of Particles, (Cambridge University Press, New York, 1995)).
While useful in certain aspects, trapping very small objects with the above (and other) previously-used approaches has been challenging. For example, with laser tweezers, magnetic tweezers and approaches based on dielectrophoresis, the maximum force available for trapping an object is generally proportional to the object's volume. In this regard, trapping sub-micron objects, and in particular, trapping objects much less than one micron in cross-section has been particularly challenging due to the scaling of the force available to trap such small objects. Moreover, for much smaller objects, heat-generating trapping approaches such as that associated with the laser power required to trap particles with laser tweezers can cause heating and photochemistry, both of which may disrupt the function of polymers or sensitive biological molecules such as delicate enzymes. Approaches based on magnetic interactions suffer from lack of generality, because the object to be trapped must be magnetic, and magnetic forces are generally small for all but a few materials, limiting the application of such approaches.
The above and other issues have presented challenges to the manipulation of small particles, and in particular to the manipulation and use of sub-micron objects.

Sub-micron object control arrangement and approach therefor

The Board of Trustees of the Leland Stanford Junior University


A telephone conferencing system includes a voice services equipment (VSE) allowing a number of telephone calls to be connected together to form a conferencing function. Parties wishing to set up a conference agree on one of their telephone numbers being designated as a “link number”. The conference participants dial into the system and then each enters the link number. The system stores the link number in a link number store when the first caller calls in. The system also checks the caller's calling line identity (CLI) with the entered link number, and the conference will not be enabled unless there is a match; thus, the conference cannot be initiated until the link number participant has called in. Any other participant calling earlier can be put on “hold”. A number of different conferences may be taking place simultaneously, and participants will be grouped together correctly in their conference in accordance with the entered link number.

Telephone or audio conferencing allows three or more people to participate in a single telephone conversation. Each person is able to hear all the other callers when they speak and the conversation can progress as if all the callers were in the same room.
Audio telephone conferencing systems exist for connection to both the analogue and digital telecommunications networks. These systems use either analogue bridges or digital signal processing to combine the audio from three or more callers and play it to all participants in the conference.
With the advance of digital systems, more complex algorithms have been employed to improve the quality of the speech heard by each caller.
Existing conferencing systems have two basic market areas, business conferencing and social chatlines. Business conferencing can be provided as a public service by the network operator, or provided locally from a company's PABX. Chatlines are usually provided by independent service providers to callers who pay a premium rate for the call whilst accessing the service. The telephone numbers for chatlines are extensively advertised and there is no restriction on callers wishing to access the service, as long as the telephone being used has not been barred from initiating premium rate calls.
There are, at present, two main ways in which a telephone conference (teleconference) can be set up automatically. The first way is for all participants to dial in to a pre-arranged number at a pre-arranged time, on a so-called "meet me" basis. The second way is for one caller to dial into a system and then control the system so that it outdials to the other participants.
Business applications for "meet-me" teleconferencing systems can use an in-house system, a bureau or a network-based system. In each case, the business or group using a conference facility will generally have been allocated a telephone number and PIN. Telephone meetings can then be held on a scheduled or ad-hoc basis by all individuals with knowledge of the telephone number and PIN. The nature of the business user in terms of permanence and administrative simplicity make this approach practical and economic.
In contrast, a network operator wishing to provide "meet-me" telephone conferencing on an ad-hoc spontaneous basis to all subscribers would find the business model with its requirement for preregistration extremely difficult to manage effectively in the domestic arena.
Therefore the current situation is somewhat bizarre in that many public network operators (PNO's) provide on-demand meet-me conference facilities for strangers (i.e. chatline services) but do not provide such facilities for friends and families that may want to talk together.

This patent is subject to a terminal disclaimer.