A simultaneous multiple rotation interface where a series of discs rotate about an eccentric camshaft. Each disc is engaged with the other by a series bearings embedded within each disc. As the camshaft rotates, each disc alternatively engages an outer shell so as to rotate the shell in the same direction as the shaft, albeit at a reduced speed.

1. Field of the Invention
The present invention generally relates to a simultaneous multiple rotation interface system. In particular, the present invention relates to a simultaneous multiple rotation interface wherein power is transmitted from an input to an output by a series of loosely seeded bearings acting in concert to provide for an extremely efficient, exceptionally powerful system.
2. Background Information
There are several types of rotation interfaces on the market today. Most commonly, these interfaces are found in speed transducers or gearboxes. Common examples of such products include: the worm speed reducer, helical reducer, coaxial reducer, and the planetary reducer. These devices are used in several areas of industry, including manufacturing, transportation, automotive, and hardware. However, all of these known products are limited in view of the present invention. Most importantly, these products do not incorporate the use of precisely aligned, seeded bearings as a mechanism to transfer power between an input and an output—this feature makes applicant's invention superior in view of devices known in the art.
The novel design of applicant's present invention overcomes the problems associated with products known in the art. For example, known rotation interfaces depend on gears, pins, or teeth to transfer power from an input to an output. As such, when these products fail, it is often the result of these teeth, pins, or gears giving way to the shear or lateral forces exerted upon them. In fact, it is well known in the art that the primary cause of failure in typical gear boxes is usually tooth breakage, or accelerated wear associated with high speed pinions. This problem is exaggerated in the common case of shock loading. However, applicant's invention handles these damaging forces extremely well. Bearings are relied upon to withstand such forces; because these bearings are able to rotate, or "give," and because the force is distributed evenly among all bearings, the invention is able to withstand forces that other products cannot.
Friction breakdown is a common problem associated with currently available rotation interfaces. There is some degree of friction along all moving internal parts, as such, regular lubrication maintenance is essential. Without such lubrication, friction build-up would surely cause a breakdown of the device from the inside out. However, the present invention reduces virtually all internal friction as it relies on a series reliable, highly durable bearings to transfer power. Employment of such bearings reduces "sliding parts" friction because these bearings effectively bear the brunt of competing forces acting on the device. Further, these bearings are aligned so that forces acting on the system are evenly distributed among all of the bearings. Elimination of "sliding parts" friction and effective force distribution among all bearings provides for an exceptionally efficient device with an extremely long working life.
Another problem associated with available rotation interfaces is loss of mechanical efficiency. Often poor design, friction, wear and tear, and poor component qualities produce a power loss between an input and an output. However, the unique construction of the present invention provides for a negligible power loss between the input and the output. That is, each bearing engages with or "grabs" the second drive at the same precise moment so that each drive is perfectly in sink with the other. Further, each bearing is aligned so as to produce a very tight component fit between the first drive and second drive, as such, there is practically no slack between component parts.
Applicant's invention is very cost-effective in view of known products. The novel design of applicant's invention provides for a manufacturing process that is relatively simple and cost effective. As such, the present invention is much cheaper than presently known, similar products. Applicant's invention, when incorporated as part of a larger, more expensive system, can greatly reduce the "components parts" cost of that system. Also, applicant's invention can readily be incorporated with cheaper products that would otherwise be cost-prohibitive. In addition, the costs of known products increases in nonlinear fashion as rotation interfaces are manufactured to provide for double or triple speed reductions. However, the present invention, through its novel design, is able to produce single, double, or triple reduction while avoiding soaring production costs.
In view of the limitations of known products, there is a great need for a rotation interface that is friction-free, durable, mechanically efficient, and cost-effective. Applicant's invention, by its novel design and straightforward manufacture process, provides an improved substitute for currently available, similar products.

Simultaneous multiple rotation interface


The present disclosure relates to a replaceable ink reservoir for installation into a printing system that has a moveable carriage for repositioning a printing portion relative to print media. The replaceable ink reservoir includes an ink reservoir that does not have an integral printing portion. Also included is an electrical storage device for storing information. The installation of the ink reservoir into the moveable carriage establishes both fluid communication between the ink reservoir and the moveable carriage and establishes electrical continuity between the electrical storage device and the moveable carriage.

The present invention relates to ink containers for providing ink to inkjet printers. More specifically, the present invention relates to an ink container that is configured for insertion into a receiving station within an inkjet printing system to establish fluid and electrical connection therewith.
Inkjet printers frequently make use of an inkjet printhead mounted within a carriage that is moved relative to a print media, such as paper. As the printhead is moved relative to the print media, a control system activates the printhead to deposit or eject ink droplets onto the print media to form images and text. Ink is provided to the printhead by a supply of ink that is either integral with the printhead, as in the case of a disposable print cartridge, or by a supply of ink that is replaceable separate from the printhead.
One type of previously used printing system makes use of the ink supply that is carried with the carriage. This ink supply has been formed integral with the printhead, whereupon the entire printhead and ink supply are replaced when ink is exhausted. Alternatively, the ink supply can be carried with the carriage and be separately replaceable from the printhead. For the case where the ink supply is separately replaceable, the ink supply is replaced when exhausted. The printhead is then replaced at the end of printhead life. Regardless of where the ink supply is located within the printing system, it is critical that the ink supply provides a reliable supply of ink to the inkjet printhead.
There is an ever present need for inkjet printing systems that make use of replaceable ink containers that are easy to install and remove. The installation of the ink container should produce reliable fluidic and electrical connection to the printer. These ink containers should be relatively easy to manufacture, thereby tending to reduce the ink supply cost. Reduction of the ink supply cost tends to reduce the per page printing costs of the printing system.
One aspect of the present invention is a replaceable ink container for providing ink to an inkjet printing system. The inkjet printing system has a receiving station mounted to a scanning carriage. The receiving station has a fluid inlet and a plurality of electrical contacts electrically connected to a printing system control portion. The replaceable ink container includes a fluid outlet configured for connection to the fluid inlet on the receiving station. Also included is a plurality of electrical contacts electrically connected to an electrical storage device. Upon insertion of the replaceable ink container into the receiving station each of the plurality of electrical contacts are so disposed and arranged on the replaceable ink container to engage each of the plurality of electrical contacts on the receiving station to operably couple the electrical storage device with the printing system control portion. Additionally, insertion of the replaceable ink container into the receiving station allows the fluid outlet disposed and arranged on the replaceable ink container to operatively couple with the fluid inlet to establish fluid communication between the replaceable ink container and the receiving station.
Another aspect of the present invention includes a capillary storage material disposed within the replaceable ink container. The fluid inlet is a hollow member that extends upwardly from a bottom surface of the receiving station so that with the replaceable ink container installed in the receiving station the hollow member compresses the capillary storage material to provide a region of increased capillarity in the capillary storage material adjacent the hollow member.

Ink container configured to establish reliable electrical and fluidic connections to a receiving station


A system abstraction layer enables selection from among at least two different processor abstraction layer components. By allowing the selection from a plurality of compressed components, better system adaptability may be achieved. For example, updates may be provided so that it is not necessary to update the entire basic input/output system each time a component of the processor abstraction layer needs to be updated. In addition, a variety of different platforms may be supported by one basic input/output system having a plurality of selectable processor abstraction layer component images.

This invention relates generally to initializing processor-based systems.
Before the operating system is called, the basic input/output system (BIOS) is responsible for initializing and booting the processor-based system. Once the BIOS has completed its tasks, it transfers control to the operating system.
The BIOS may include at least three different levels. The lowest level may be the processor abstraction layer (PAL) that communicates with the hardware and, particularly, the processor. A middle layer is called the system abstraction layer (SAL). The SAL may attempt to correct correctable errors after they are detected and reported by the PAL. The uppermost layer, called the extensible firmware interface (EFI), communicates with the operating system and, in fact, launches the operating system.
In some processor-based systems, more than one PAL component may be provided. For example, in one implementation, two processor-specific components, which may be denominated PAL_A_SPECIFIC and PAL-B, may be provided. These two processor-specific components may typically be stored in system flash and may have a functionality akin to that normally handled by microcode. A third component called PAL_A_GENERIC is processor-independent and is the first component to execute in response to a restart event in some architectures.
The PAL_A_GENERIC component searches a firmware interface table (FIT) to locate a suitable onboard processor compatible with PAL_A_SPECIFIC and authenticates the component. The FIT, also stored in system flash, contains starting addresses and sizes for firmware components outside the protected boot block. The PAL_A_SPECIFIC authenticates the PAL-B component. The PAL_A_SPECIFIC then discovers the PAL-B through a FIT constructed by the original equipment manufacturer detailing, where in the system flash, PAL-B can be found.
After authentication, the PAL_A_SPECIFIC passes control to the original equipment manufacturer provided SAL-A component code. The control flow at this point can be recovery in the case of failed signature verification of the PAL-B or in the case of an incompatible PAL-B with respect to a particular processor stepping.
Only a single PAL-B component is supported because of flash memory space constraints. When it is desired to update the PAL-B in system flash with a newer version of PAL-B, the customer may use a so-called crisis recovery flow. The crisis recovery flow entails user intervention including flipping jumper switches and inserting a disk.
Thus, there is a need for a way that enables updating of PAL components without the need for user intervention.

Providing selectable processor abstraction layer components within one BIOS program


Apparatuses are provided for thermally conditioning material. The apparatus includes a plate having a top surface for receiving material, a temperature controller connected to control the temperature of the top surface of the plate and the temperature controller is controlled by a computer controller. In a preferred embodiment, three tubular shaped ceramic support members, each containing a bore, are provided to support the material and a negative pressure source is provided in fluid communication with the bores. In addition, three lift elements having contacting ends are slidably disposed through receiving holes in the thermal conditioning plate and aligned to support the material on the contacting ends. Preferably, at least one of the lift pins contains a bore with a sensor positioned to detect the presence of material on the contacting end of the lift pin and provide a signal to the computer controller that can be used to control the negative pressure source and the relative movement of the plate and lift pins. Also, in a preferred embodiment, the apparatus includes an exhausted cover providing for a stagnation region adjacent to the material during operation, thereby providing for more uniform heat transfer to the material.

1. Field of the Invention
The present invention relates to an improved thermal conditioning apparatus and methods of using the same. More particularly, the present invention relates to improved thermal conditioning plate and method for use in controlling the temperature in the placement and curing of photoresist on a semiconductor substrate wafer.
2. Description of the Invention Background
Integrated circuits are typically constructed by depositing a series of individual layers of predetermined materials on a wafer shaped semiconductor substrate, or "wafer". The individual layers of the integrated circuit are, in turn, produced by a series of manufacturing steps. For example, in forming an individual circuit layer on a wafer containing a previously formed circuit layer, an oxide, such as silicon dioxide, is deposited over the previously formed circuit layer to provide an insulating layer for the circuit. A pattern for the next circuit layer is then formed on the wafer using a radiation alterable material, known as photoresist. Photoresist materials are generally composed of a mixture of organic resins, sensitizers and solvents. Sensitizers are compounds, such as diazonaphtaquinones, that undergo a chemical change upon exposure to radiant energy, such as visible and ultraviolet light, resulting in an irradiated material having differing solvation characteristics with respect to various solvents than the nonirradiated material. Resins are used to provide mechanical strength to the photoresist and the solvents serve to lower the viscosity of the photoresist so that it can be uniformly applied to the surface of the wafers. After a photoresist layer is applied to the wafer surface, the solvents are evaporated and the photoresist layer is hardened, usually by heat treating the wafer. The photoresist layer is then selectively irradiated by placing a radiation opaque mask containing a transparent portion defining the pattern for the next circuit layer over the photoresist layer and then exposing the photoresist layer to radiation. The photoresist layer is then exposed to a chemical, known as developer, in which either the irradiated or the nonirradiated photoresist is soluble and the photoresist is removed in the pattern defined by the mask, selectively exposing portions of the underlying insulating layer. The exposed portions of the insulating layer are then selectively removed using an etchant to expose corresponding sections of the underlying circuit layer. The photoresist must be resistant to the etchant, so as to limit the attack of the etchant to only the exposed portions of the insulating layer. Alternatively, the exposed underlying layer(s) may be implanted with ions which do not penetrate the photoresist layer thereby selectively penetrating only those portions of the underlying layer not covered by the photoresist. The remaining photoresist is then stripped using either a solvent, or a strong oxidizer in the form of a liquid or a gas in the plasma state. The next layer is then deposited and the process is repeated until fabrication of the semiconductor device is complete.
Photoresist and developer materials are typically applied to the wafer using a spin coating technique in which the photoresist is sprayed on the surface of the wafer as the wafer is spun on a rotating chuck. The spinning of the wafer distributes the photoresist over the surface of the material and exerts a shearing force that separates the excess photoresist from the wafer thereby providing for a thin layer of photoresist on the surface of the wafer. Following the spin coating of the wafer, the coating is heated, or soft baked, to remove the volatile solvent components, thereby hardening the photoresist.
The properties of the photoresist, and, therefore, the suitability of the photoresist for use in the subsequent processing steps, are largely dependent upon the ability to uniformly harden the photoresist. The heating of the photoresist can be performed either by convection, infrared heating or through the use of a hot plate. While convection and infrared heating can be performed in bulk, the use of a hot plate to individually bake the wafer on a heating surface has become the preferred method. This is because the hot plate method provides for rapid heating of the wafer and the heating occurs from the wafer-photoresist interface toward the surface of the photoresist, which tends to drive off gas pockets present in the photoresist and also prevents the formation of a surface crust on the photoresist. In order for the hot plate soft baking technique to be cost effective in comparison with the batch techniques, an automated wafer handling system must be used to maximize the throughput of the wafers. In addition, cooling assemblies are often employed to reduce the cooling time for the wafer so as to enhance the overall throughput of the system. As such, the heating and cooling system are directly tied into the automated wafer handling system.
A problem that arises with the prior art integrated spin coating systems is that when the heating or cooling assemblies must be repaired or replaced, extensive and costly amounts of downtime occur because of the integration of the system. The costs are especially significant in a clean room environment in which all operations in the clean room have to be shut down until cleanliness can again be achieved at a cost of thousands of dollars an hour. For instance, if the heating element must be replaced in the hot plate, not only must the system be shutdown for the replacement, but following the replacement of the heating element the system will have to be recalibrated prior to restarting the system and the cleanliness procedure followed to reestablish cleanliness in the clean room.
In the operation of the heating or cooling assemblies, the wafers are placed either directly upon the heating/cooling surface of the plate, or, alternatively, upon a plurality of receiving pins, from which the wafers are placed on the surface using an assembly such as that described in U.S. Pat. No. 4,955,590 issued to Narushima et al. The use of receiving pins and/or a table that reciprocates is a preferred method of loading in the industry because it provides access to the exposed uncoated surface for the loading and unloading of the wafers with automated handling equipment when the wafer is seated upon the receiving pins. One problem with this method as discussed in the Narushima patent (col. 1, lines 38-41) is that, if the receiving pins are lowered, the air resistance causes the wafer to float, which can result in misalignment of the wafer on the pins. The Narushima patent (col. 4, lines 37-44) indicates that by moving the table and not the pins this problem is eliminated, because the wafer is not moved; however, the raising of the table will exert a force on the bottom of the wafer that is analogous to the force exerted when the wafer is lowered, thus floating of the wafer will occur even when the table is raised and the pins are stationery. A possible solution to this problem suggested in the Narushima patent (col. 5, lines 3-6) is to draw a vacuum through the distal end of the receiving pins to chuck the wafer against the distal end of the pins to prevent movement. While this solution appears to provide a more plausible method of preventing the wafer from floating, the method greatly complicates the overall design of the system. This is because the wafer must be removed from the receiving pins requiring that the vacuum be released when the wafer reaches the table either through the use of a sensing system or by moving the table at a speed so as to dislodge the wafer from the receiving pins; however, this type of mechanical release would most likely result in misalignment problems and could also potentially damage the wafer. As such, there is need for an improved apparatus and method for receiving wafers, and plate-like material in general, in a plate-like material treating apparatus.
A number of methods exist in the prior art to hold the wafer in position on the surface of the plate following the transfer of the wafer from the receiving pins to the plate. One method is to directly place the wafer on the plate surface and to apply a vacuum through a hole in the surface adjacent to the wafer to hold the wafer in place, as discussed in the Narushima patent (col. 2, lines 50-55). A problem with this method is that uneven heating or cooling of the wafer occurs especially in the vicinity of the holes provided for the receiving pins and for the applying the vacuum and due to thermal maldistributions in the remainder of the plate. An alternative to directly placing the wafer on the surface has been to use ball shaped supports that are press fit into the top surface of the plate thereby creating an air layer between the wafer and the surface that would tend to more uniformly distribute the transfer of energy. However, the use of ball shaped supports reintroduces the problem of securing the wafer on the surface. In addition, the air layer between the wafer and surface must be very small (-0.1 mm) in order to maintain the desirable heat transfer characteristics associated with the plate heating/cooling technique, thus requiring that very small ball shaped supports be machined and precisely attached the heat transfer surface of the plate. Accordingly, a need exists for an improved apparatus and method for supporting of plate-like material during thermal treating operations.
During the heating of the wafer on the plate, the volatile solvents in the photoresist are evaporated and must be exhausted to prevent condensation in the system and to provide environmental control of the vapors. In the prior art, as shown in FIGS. 1 and 2, as a wafer is heated on a hot plate 3, either by drawing air over the wafer 2 from the annular region 4 and exhausting the vapor through a perforated plate 5 and exhaust port 6 from above the wafer 2 or drawing air through the perforated plate 5 over the wafer from above the wafer and exhausting the vapors from the annular region 4 surrounding the wafer 2. The exhausting of the solvent vapors requires a large throughput of air that must be drawn from outside of the heating assembly resulting in cool air being drawn over the surface of the wafer. The direct contact of the cool air with the surface can produce uneven cooling of the surface resulting in nonuniformities in the photoresist coating. Also, the outside air can introduce contamination directly onto the surface of the photoresist further degrading the coating. In view of the aforementioned, there is a need for an improved exhaust system and more generally a need for an improved thermal conditioning apparatus and method.
The present invention is directed to a self-contained thermal conditioning apparatus and methods of using the same which overcomes, among others, the above-discussed problems so as to provide a more easily controlled and more uniform photoresist coatings for use in semiconductor production.


A method transmits a certain sequence of symbols, where a frame is constructed of a certain number of consecutive symbols. The symbols belonging to the sequence are transmitted using at least two antennas and the transmission of the sequence of symbols is with a certain transmission pattern. The transmission of the sequence of symbols is started from a predefined antenna and the transmission pattern is started from the beginning in the beginning of each frame. Also disclosed is an apparatus and a network element for controlling the transmission of a sequence of symbols.

1. Field of the Invention
The invention relates in general to transmission of a certain sequence of symbols. In particular the invention relates to diversity transmissions where the symbols belonging to the sequence are sent using at least two antennas.
2. Brief Description of Related Fields
In cellular networks the downlink and uplink radio transmissions comprise synchronization channels, which can be special synchronization symbols. Using the information carried in the synchronization symbols, for example, the receiver can determined the timing of the transmission. Information is usually sent in frames, and the frames consist of a certain number of time slots. The time slots, in turn, consist of a certain number of symbols. If synchronization symbols are used, they can be sent, for example, once in each time slot. It is also possible to send synchronization information in bursts, so that more information is sent at a time, but synchronization information is sent less frequently than once in a time slot. From the synchronization information it is possible to determine both the time slot timing and the frame timing, i.e. where time slots and frames start.
The synchronization symbols may carry also other information than just indicate timing. For example, in Wideband Code Division Multiple Access (WCDMA) cellular networks the synchronization symbols carry certain information about the spreading code that a base station uses to spread the downlink transmissions. In a handover, for example, the mobile station entering a new cell can determine the part of the downlink spreading code with the help of the synchronization symbols. The mobile station needs to know the spreading code in order to find out the control information transmitted via the common control channel. Otherwise it cannot, for example, communicate with the radio access network after power up or in a handover situation receive from the new cell cell-specific control information that is needed to perform the handover.
Traditionally information is transmitted over radiolink using a single antenna. Transmission diversity refers to sending information via more than one antenna. The transmitted information can be, for example, encoded so that the transmitted symbol flows are not equal, but the original information flow can be determined from each transmitted symbol flow. The receiver can, for example, choose special decoding scheme in case transmission diversity is used and deduce the transmitted information. The synchronization symbols can carry information also about the use of some transmission diversity scheme. It is important that the receiver can determine the sent synchronization symbol correctly. Otherwise, for example, it may fail to identify the transmission diversity and encoding schemes that are used.
FIG. 1 represents a typical WCDMA cell 100, where there is a base station 101 in the middle of the cell. There are also two mobile stations 102 and 103 in the FIG. 1, and the communication between each mobile station and the base station is indicated with arrows. The base station broadcasts common control information to all the mobile stations in the cell, and it spreads this common control information with a certain spreading code. In a WCDMA system, a spreading code usually consists of two parts: a long scrambling code CS and a short channelization code CC. The scrambling code is effective to eliminate, for example, the effect of multipath propagation. The channelization codes that are used within a cell are orthogonal, and they are effective to distinguish, for example the transmission to each mobile station. In a WCDMA system, within a cell a same scrambling code CS may be used for all downlink transmissions. The downlink transmission are synchronized, and therefore the different channelization codes are enough for successful despreading of the transmitted signals. In the neighboring cells, other scrambling codes are used so that adjacent cells do not disturb each other's transmissions.
The use of spreading codes in downlink transmission is presented in FIG. 1, where the arrow 111 represents the common control information broadcast. The spreading code can be presented as the product of the scrambling and channelization codes CCC=CS CC. When entering a new cell, the mobile station can determine the downlink scrambling code CS from the broadcast transmission the base station sends. The channelization code related to common control information is typically a fixed constant throughout the WCDMA system, so after determining the downlink scrambling code and the frame timing, the mobile station can determine the common control information.
The arrow 112 in FIG. 1 represents the downlink transmission to the mobile station 102, and the arrow 113 represents the downlink transmission to the mobile station 103. The spreading code CD1 for the downlink connection to the mobile station 102 is CD1=CS CC1, and the spreading code CD2 for the downlink connection to the mobile station 103 is CD2=CS CC2. Since the uplink transmissions are not synchronized and each mobile has its own radio channel from the mobile station to the base station, each mobile station may use a specific scrambling code, and various channels, for example, to a certain mobile station may be separated using various channelization codes. The downlink and uplink spreading codes for connections terminating to a mobile station are usually established either when a mobile station enters a new cell or when a new connection is established between the mobile station and the radio access network.
FIG. 2 shows some of the common channels a base station in a WCDMA system generally transmits The pilot symbols are transmitted over a common pilot channel (CPICH) 201. The pilot symbols are usually sent 100% of the duty cycle. The pilot symbols are predetermined, and CPICH is spread using the downlink scrambling code CS and a fixed channelization code.
The synchronization channel (SCH) 202 occupies typically 10% of the duty cycle in the beginning of each time slot 210. The frame 211, which comprises a certain fixed number of time slots, is also presented in FIG. 2. The synchronization channel carries two synchronization codes: a primary synchronization code 203 and a secondary synchronization code 204. These codes are transmitted simultaneously within one symbol period. Both the primary and secondary synchronization codes can be modulated, for example, with the same symbol, and because the codes have good crosscorrelation properties the receiver can distinguish the codes. A mobile station entering a new cell or measuring a new cell in the neighborhood may always receive successfully information broadcast over the SCH.
The primary synchronization code is a constant code that denotes the beginning of the time slots. The secondary synchronization codes, which form a synchronization code sequence or word, indicate the timing of the frames. In addition to the frame timing, the second synchronization code sequence within a frame indicates the scrambling code group to which the downlink scrambling code the base station uses belongs. A mobile station entering a new cell may determine the downlink scrambling code, for example, by testing the scrambling codes of the indicated scrambling code group on the CPICH. The correct scrambling code CS is the one that with the known channelization code produces from the received radio signal the known transmitted pilot symbols.
Once the scrambling code CS has been determined, the received pilot symbols may be used, for example, for determining the complex channel coefficient. In general, the radio signal that is received is not exactly the same as the transmitted one. The signal may experience changes in amplitude and phase, and these changes are time-dependent. They are taken into account using the complex channel coefficient h when the despread signal is processed. An estimate ĥ for the channel coefficient can be determined by comparing the received pilot symbols to the known transmitted pilot symbols. The channel coefficient may be assumed to be constant during the time over which the pilot symbol and the studied symbol are transmitted.
Common control information is transmitted using, for example, a Primary Common Control Physical Channel (PCCPCH) 205. PCCPCH is transmitted 90% of the duty cycle, at the time when the synchronization symbols are not sent. It is spread using a predetermined channelization code and the downlink scrambling code, as discussed above. After the scrambling code has been identified, the mobile station may despread the CCPCH information from the spread signal it receives. The information may be, for example, information related to the logical Broadcast Control Channel (BCCH). The mobile station needs the BCCH information, for example, to start communicating with the radio access network after power up or to make a successful handover.
FIG. 2 represents a situation where the base station uses only one antenna TX1 for broadcasting information. When transmission diversity is employed, there are at least two antennas where the information may be transmitted. It is preferable that each antenna transmits its own pilot signal, so that the channel coefficient estimates can be determined for each antenna. The radio waves emitted for the two transceivers may propagate in different ways to the antenna of the mobile station.
FIG. 3 represents some broadcast channels when transmission diversity and two antennas TX1 and TX2 are in use. The antenna TX1 transmits the common pilot channel CPICH 201 similarly as when no transmission diversity is employed. The antenna TX2 transmits an auxiliary pilot 301. The synchronization symbols may be transmitted using only one antenna or both antennas. In time switched transmit diversity (TSTD) both antennas are used to transmit the symbols, one at a time. FIG. 3 shows how the synchronization symbols are transmitted using TSTD and an alternating transmission pattern. For example, the synchronization symbol 302 is transmitted from the antenna TX1 and the synchronization symbol 303 is transmitted from the antenna TX2. Each synchronization symbol carries both the primary and the secondary synchronization code.
The common control information may be also transmitted from both antennas TX1 and TX2. In this case the BCCH information, for example, is encoded before it is transmitted over the PCCPCH channel. Space time transmit diversity (STTD), for example, specifies that from the primary antenna TX1 the symbols are transmitted as such, i.e. the sequence of transmitted symbols is S1, S2, S3, S4, . . . . From the second antenna TX2 the sequence of transmitted symbols starts in the following way: −S2*, S1*, −S4*, S3*, . . . , where the asterisk indicates the complex conjugate. FIG. 3 presents the PCCPCH data 304 transmitted from the antenna TX1 and the PCCPCH data 305 transmitted from the antenna TX2. It is possible also to use the space time transmit diversity for the BCCH information but transmit all the synchronization symbols from one antenna.
The base station may indicate the use of a diversity scheme and two transceivers, for example, by transmitting a specific message on a broadcast channel or modulating the synchronization symbols. A certain synchronization symbol value indicates that the STTD is on, and another value indicates that it is off. The mobile station may also determine the use of a diversity scheme by detecting the auxiliary pilot symbols. The mobile station may also use all three indicators of the diversity scheme.
When the mobile station detects the presence of STTD using the synchronization symbol, the value of the synchronization symbol needs to be determined reliably. When a certain symbol needs to be determined, the effect of the channel coefficient has to be taken into account. The mobile station receives the following signal rr=hsSCH+n where h represents the complex channel coefficient, sSCH represents the synchronization symbol and n represent the noise.
When the received signal r in multiplied by the complex conjugate of the channel coefficient estimate ĥ*ĥ*r=ĥ*(hsSCH+n)=ĥ*hsSCH+ĥ*n the result is the synchronization symbol scaled with a scalar ĥ*h and the term related to noise. From here it is quite straightforward to infer the value of the synchronization symbol.
Above, the synchronization symbols have been used as an example of a sequence of symbols that is transmitted using two antennas. The problem is that when the TSTD diversity scheme is in use, the mobile station cannot necessarily distinguish from which antenna a certain synchronization symbol, or any other symbol that is transmitted using a time switched diversity scheme, is transmitted. Consider, for example, a situation where a certain sequence of symbols is transmitted once is every time slot, and a frame consists of an odd number of time slots. If the symbols belonging to the sequence are transmitted using a time switched diversity scheme, two diversity antennas are used and the transmission pattern is an alternating pattern, in a certain time slot the symbol belonging to the sequence is transmitted from one antenna in every other frame and in the rest of the frames from the other antenna. Therefore the mobile station does not know, which channel coefficient estimate to use for a symbol sent in a certain time slot with a time switched transmission scheme.
To obtain a reliable result, the signal transmitted by the primary transceiver has to be processed with the channel coefficient estimate ĥ2 determined from the primary pilot and the signal transmitted by the secondary transceiver has to be processed with the channel coefficient estimate ĥ2 determined from the auxiliary pilot. Not knowing from which antenna a certain symbol is transmitted causes unnecessary interference to the decision determining which symbol was sent. In case of synchronization symbols, this may cause that the mobile station cannot utilize the transmission diversity of, for example, the common control information for enhancing the quality of the received signal. Consequently, if the transmission diversity is in use, but the receiver does not notice this, the quality of the received common control signal may be poorer than in a case where no transmission diversity is applied.
The object of the invention is to provide a versatile method for transmitting a sequence of symbols using at least two antennas. A further object of the invention is that the method enables to determine unambiguously from which antenna a symbol belonging to sequence is transmitted.
The objects of the invention are achieved by starting the time switched transmit diversity pattern of the sequence of symbols always from the same antenna in the beginning of a frame and by using the same pattern in each frame.

This patent is subject to a terminal disclaimer.

Method for transmitting a sequence of symbols


The invention relates to a lithographic apparatus including an illumination system configured to condition a radiation beam, a patterning device support constructed to support a patterning device, the patterning device being capable of imparting the radiation beam with a pattern in its cross-section to form a patterned radiation beam, a substrate support constructed to hold a substrate; a projection system configured to project the patterned radiation beam onto a target portion of the substrate, and an encoder-type measurement system configured to at least during projection of the patterned radiation beam onto a target portion of the substrate continuously determine a position quantity of a patterning device supported on the patterning device support using a grid or grating provided on the patterning device.

A lithographic apparatus is a machine that applies a desired pattern onto a substrate, usually onto a target portion of the substrate. A lithographic apparatus can be used, for example, in the manufacture of integrated circuits (ICs). In such a case, a patterning device, which is alternatively referred to as a mask or a reticle, may be used to generate a circuit pattern to be formed on an individual layer of the IC. This pattern can be transferred onto a target portion (e.g. including part of, one, or several dies) on a substrate (e.g. a silicon wafer). Transfer of the pattern is typically via imaging onto a layer of radiation-sensitive material (resist) provided on the substrate. In general, a single substrate will contain a network of adjacent target portions that are successively patterned. Conventional lithographic apparatus include so-called steppers, in which each target portion is irradiated by exposing an entire pattern onto the target portion at once, and so-called scanners, in which each target portion is irradiated by scanning the pattern through a radiation beam in a given direction (the "scanning"-direction) while synchronously scanning the substrate parallel or anti-parallel to this direction. It is also possible to transfer the pattern from the patterning device to the substrate by imprinting the pattern onto the substrate.
In a scanning type lithographic apparatus, a patterning device (e.g. a mask) is carried by a patterning device support, also referred to as mask table or patterning device table. While generating a pattern on a target portion of a substrate, the patterning device support performs scanning movements along a line of movement, in a single scan direction or scanning in both (i.e. opposite) directions along the line of movement. When a reversal of direction takes place, the patterning device support is decelerated and accelerated between the successive scanning movements. Also, the patterning device support is accelerated and decelerated before and after each scanning movement in a specific direction. Conventionally, the scanning movements are made with constant velocity. However, the scanning movements may also at least partly be made with varying velocity, e.g. the movements including at least part of the deceleration and/or acceleration phases.
The patterning device support holds the patterning device in a manner that depends on the orientation of the patterning device, the design of the lithographic apparatus, and other conditions, such as for example whether or not the patterning device is held in a vacuum environment. The patterning device support may include a frame or a table, for example, which may be fixed or movable as required. The patterning device support (and its control system) may ensure that the patterning device is at a desired position, for example with respect to the projection system.
The patterning device is coupled to the patterning device support through a clamp. Conventionally, the patterning device is coupled to the patterning device support through a vacuum clamp which may be implemented as one or more vacuum pads provided on the patterning device support, where at least a part of a circumferential area of the patterning device is held onto the vacuum pads. By the clamp, a normal force between adjacent surfaces of the patterning device and the patterning device support is generated, resulting in a friction between contacting surfaces of the patterning device and the patterning device support. The vacuum pads may include one or more openings coupled to a gas discharge and supply system. Instead of a vacuum coupling between the patterning device and the patterning device support, other forms of couplings based on friction between the patterning device and the patterning device support are conceivable, such as electrostatic or mechanical clamping techniques to hold the patterning device against the patterning device support.
In an ongoing development, increasing throughput requirements placed on lithographic apparatus lead to increasing scanning velocities. Consequently, deceleration and acceleration of the patterning device support increase. In the deceleration and acceleration phases, increased inertia forces act on the patterning device support and on the patterning device.
It is known that inertia forces acting on the patterning device support and the patterning device may lead to slip of patterning device and patterning device support relative to each other. The slip usually is in the order of nanometers. For relatively low decelerations and accelerations, the slip has appeared to be low and approximately constant over time, changing its direction with each deceleration/acceleration phase. In such circumstances, the slip may be ignored if it is sufficiently low, or the slip may be compensated by suitably calibrating a positioning device controlling the position (and hence, the movement) of the patterning device support and/or the substrate stage.
However, with increasing decelerations and accelerations, the slip occurring between the patterning device and the patterning device support increases, and becomes variable and unpredictable. Factors influencing the amount of slip may include, but may not be limited to, a flatness and roughness of the surfaces of the patterning device and the patterning device support engaging each other, a humidity of the atmosphere(s) in which the patterning device and the patterning device support are handled, a contamination of the patterning device or the patterning device support, and a degree of vacuum when the patterning device is held on the patterning device support by vacuum pads. Thus, a calibration of the positioning device will not lead to a correct positioning of the patterning device support and/or the substrate stage under the circumstances of high inertia forces.
Not only the speed of movement and acceleration of the patterning device support may tend to increase, also, accuracy requirements on the lithographic apparatus may become more stringent. Therefore, slip of the patterning device becomes less tolerable, as slip of the patterning device may result in a position error of the pattern projected onto the substrate.
It has been proposed to provide mechanical solutions to avoid slip between the patterning device support and the patterning device, such as enhanced clamping force between the patterning device support and the patterning device and/or an optimized clamp design. Also it has been proposed to provide a patterning device pushing device which exerts a compensation force on a side of the patterning device to avoid slip between the patterning device and the patterning device. However, none of these solutions is capable of sufficiently avoiding the imaging errors, in particular overlay errors at higher acceleration levels of the patterning device support.
In another solution a feed-forward compensation controller was provided in which slip between patterning device and patterning device support was taken into account. However, the variation in the amount of slip at a certain acceleration level is unpredictable. As a result, feed-forward compensation may not provide a reliable compensation for the slip between patterning device and patterning device support.
In EP 1 918 777, the contents of which are herein incorporated by reference, it is proposed to provide a support position sensor to measure a position of the support relative to a first structure of the lithographic apparatus, and a patterning device position sensor to measure a position of the patterning device relative to a second structure of the lithographic apparatus. A control device is provided to determine a correlation between the position of the patterning device and the position of the support from the position measured by the support position sensor, the position measured by the patterning device position sensor, and mutual positions of the first and second structures. On the basis of this correlation, the amount of slip between the patterning device and the patterning device support is determined and compensated in the position control of the patterning device support.

Lithographic apparatus, and patterning device for use in a lithographic process


A method for providing an information unit to a user is described, wherein the information unit describes an object having a predetermined spatial relationship to the user. The method includes detecting a kind of movement or a position of the user. Depending on the detected kind of movement or the position of the user, a geographic selection criterion is adjusted, wherein, depending on the predetermined spatial relationship of object to user, the geographic selection criterion specifies whether the information unit is provided or not. If a location of the user is located such with respect to a geographic position of the user that the geographic selection criterion is met, the information unit for the object is reproduced. An advantage is that the concept may be employed in applications in which the user gets into different environments and situations which, in turn, require different geographic selection criteria.

1. Field of the Invention
The present invention relates to a method and devices for the location-dependent provision and/or reproduction of information to a user.
2. Description of the Related Art
Systems for location-dependent information reproduction are known in the art and are employed, for example, in the area of museums for automatic tours through the museum. The information units to be reproduced describe various objects located at different locations. The systems have knowledge of the user location and of the locations of the information units. The selection of the information unit to be reproduced from the plurality of information units is performed via so-called selection criteria. These selection criteria include, among other things, geographic selection criteria and determine, for example, in which distance to the user an object may maximally be situated for the corresponding information unit to be included in the short list of information units to be selected, one of which, in turn, is finally to be reproduced. Each geographic selection criterion, such as the maximum distance of an object to the user, is designed for the specific application of the system, such as in the case of the museum visitor tour system for the corresponding conditions applying to a visit to a museum.
Current systems of the type described above fail when it is attempted to employ them in applications in which there are environmental and situational conditions that change and/or vary considerably, because in situations and/or environments for which they are not designed, they lead to a rather useless selection of information units to be reproduced. When the museum guide described above is employed in an outdoor museum, for example, in which the visitors walk both through exhibition rooms and along outdoor paths, the configuration of the geographic selection parameters to one of the two environments and/or situations, that is outdoors or indoors, leads to a rather useless selection in the respective other environment.
An example for a system of the type described above is described, for example, in DE 10039663 A1.
Accordingly, there is a need for systems for location-dependent information reproduction that may be employed universally and, in addition, lead to a more efficient selection of the information units to be reproduced.
DE 19841169 C1 describes a method and a device for the provision of informational data in connection with a GPS system. The informational data in a data carrier are reproduced depending on the current location data and the current movement speed data via an optical and/or acoustic output unit. More specifically, the selection of the information file to be reproduced from the provided information files is based on finding out first the relevant informational data for a certain distance ahead and then replaying them in the order that the next informational data to be replayed is the one which may be replayed at top priority in the time window until the forecast end point of its validity for the route. Accordingly, a sequential application of fixed selection criteria is used for the selection of information to be reproduced. First, a selection criterion is applied which, from all information, only selects those describing the objects that are relevant for a forecast path ahead and/or can be reproduced along a certain route segment. From this information, in turn, those with top priority are filtered out, wherein it is taken into account, however, that the user is going with a detected speed and that, therefore, the route segments concerned by the information are traveled through for different periods of time depending on speed, so that only that information is replayed that is sufficiently short with respect to its replay duration.
DE 69310938 T2 describes a system with electronic verbal tourist instructions. The system allows searching for information on database with respect to the immediate environment of a selected or determined position, and passing it on to the user, namely on request or automatically. On the one hand, upon request for information by the user, the system is capable of displaying suitable answers with respect to the respective vicinity with increasing magnitude of distance and/or listing them verbally. According to another mode of operation of the system, the information output to the user is performed automatically, thereby allowing the user to know the information hierarchically classified as the most important or most interesting one of the location where the system is located in the database. The objects described in the database have their precise locations in their description for location-dependent reproduction. Moreover, the information is stored such that a decision of access is permitted according to the degree of accuracy desired for the information.

Location-dependent information reproduction with adaptation of a geographic selection parameter

Fraunhofer-Gesellschaft zur Foerderung der angewandten Forschung e.V.


A self-assembly micro fan includes a body, a plurality of blades and flexible joints, with any one of the blades being connected to the body by one of the flexible joints while each flexible joint is regarded as a pivot to move the blade connected therewith to have an angle relative to a radial direction of the body. Besides, each of the flexible joints has plural link members or at least one link member and extension member to provide variable types of shape of the micro fans, so that the air driving efficiency of the self-assembly micro fan is improved.

1. Field of the Invention
The present invention relates to a fan and, more particularly, to a micro fan realized by micro electromechanical system technology.
2. Description of the Related Art
A conventional self-assembly micro fan is described in Taiwan Patent No. 1275563 entitled "SELF-ASSEMBLY STRUCTURE CONSTRUCTED BY POLYIMIDE FILM," which is a micro fan realized by self-assembly technique of micro electromechanical systems technology. Referring to FIG. 1, the conventional micro fan 9 includes a body 91, a plurality of blades 92, and a plurality of flexible joints 93. The body 91 has a hub 911 positioned at a center of an outer ring 913 and connecting with the outer ring 913 by a plurality of actuators 912. The blades 92 are radially arranged along an outer periphery of the outer ring 913. The plural flexible joints 93 respectively connect between the blades 92 and the outer ring 913.
Now please turn to FIG. 2. The flexible joints 93 of the conventional micro fan 9 realized by self-assembly technique is constructed by polyimide film. In manufacture of the micro fan 9, the flexible joints 93 are performed with a reflow process in an oven and thus bent owing to thermal contraction. Consequently, through the thermal-caused bending, each blade 92 is lifted and pivots on the flexible joint 93 connected therewith and has an angle relative to a radial direction of the body 91, and hence the manufacture of the micro fan 9 is accomplished.
Generally, for any one of the blades 92, because the flexible joint 93 linking the blade 92 and the outer ring 913 is only a squared member while the blade 92 and the outer ring 913 merely connect with two ends of the flexible joint 93 respectively, an area for combination between the blade 92 and the flexible joint 93 is obviously limited, and thus the angle between the blade 92 and the radial direction of the body 91 is also limited. Furthermore, owing to the crude combination between the blade 92 and the flexible joint 93, the blade 92 can only be simply lifted without curvature or an inclined inner edge, and thus the air-driving efficiency of the conventional micro fan 9 is limited too. Hence, there is a need for an improvement over the conventional micro fan 9.

Sunonwealth Electric Machine Industry Co., Ltd.


A gas burner includes an ignition mechanism and a gas conduit for conducting gas from a gas supply, through a gas inlet, to a burner nozzle. The gas conduit includes an ignition gas conduit and a separate main gas conduit, the ignition and main gas conduit being generally parallel to each other with the main gas conduit being disposed within the ignition gas conduit. The gas inlet, at one end of the gas conduit, is in communication with the ignition gas conduit, through an ignition nozzle. The ignition mechanism is mounted in the ignition gas conduit, downstream of the ignition nozzle. The main gas conduit is in communication with the ignition gas conduit through the burner nozzle. The burner nozzle is located downstream of the ignition mechanism.

According to a first aspect, the present invention relates to a gas burner of the kind defined in the preamble of claim 1, and according to a second aspect relates to a method of igniting a gas burner.
Gas burners of this kind have many different applications, among these being soldering, seam-welding, heating, drying, shrinking or burning applications. The burner unit will at times have a considerable size, such as in the case of roof burners, which causes difficulties in igniting the flame. Furthermore, positioning of the igniter or spark plug adjacent the burner nozzle requires the provision of a long cable to the igniter, therewith causing difficulties. The presence of a pilot flame that burns during rest periods which is located in the vicinity of the burner nozzle and functions to ignite the full flame is also disadvantageous, for instance with respect to heat development during rest periods and unnecessary gas consumption.

Gas burner provided with ignition devices


A device for making holes in the ground for easy insertion and planting of garden plants which are rooted in small containers. The tool has a least one frustro-conical or frustro-pyramidal shaped projection forming a cone extending down projecting downward from a base of a stirrup having a means for attaching a handle defining a cylinder formed at the top of the stirrup. A long handle may project up from the tool body with a large aperture just above the tool body into which the user's foot may be placed to help in pushing the projections into the ground to make holes sized for planting garden plants. The tool body can be connected to the handle rigidly or may swivel if desired. In one embodiment a plurality of frustro-conical shaped projections extend from a tool body. The projections are assembled onto a tool body in such a way that the distance between each of the projections is easy adjustable.

A tool is needed to make pre-shaped holes in the ground for planting garden plants from trays and in particular for planting garden plants which are purchased pre-tooted in trays referred to as flats from garden stores. When plants are removed from the tray, the dirt generally comes out with the roots and in shaped in a generally pyramidal shape. A tool which makes a hole in the ground corresponding in shape with the root ball of the plant is desirable to minimize disturbance of the soil in close planting environments, to minimize bending over and back strain, to exert sufficient pressure on the soil to produce the desired depression depth, and to minimize the mess caused by digging holes with spades, shovels or trowels whereby loose dirt is spread over mulch, or other ground covering. Further, a tool which can make three or more holes at a desired spacing is handy. The projections which make these holes should be easily adjustable so that spacing can be changed as desired.
Ramsey teaches a tool which makes conical holes spaced apart in a fixed array. Ramsey does not produce pyramidal holes and the projections are not adjustable with respect to one another. Further, Ramsey's tool does not provide a spot for a user's foot when more force is needed to press the tool into the ground.


A digital signal phase detector comprising a first circuit arranged to provide a phase difference signal representative of both the clock period of a clock signal and the difference in phase between the clock and a data signal, and a second circuit arranged to provide a reference signal representative of the clock period of the clock signal. At least one of the first and second circuits is coupled to a set point control signal and the corresponding output signal is representative of that set point control signal. A comparison of the phase difference signal with the reference signal provides an indication of the difference between the desired set point of the circuit and the phase difference between the clock and the data signal. A corresponding method of digital signal phase detection is also provided.

The present invention relates to a method and apparatus for electrical signal phase detection and a system incorporating the same.
Digital communication equipment is used in a wide variety of devices for the transmission of digital information. Such information includes numerical data in computers and digital encodings of voice in telecommunications systems.
In the course of transmission of digital signals from a transmitter to a receiver, the digital signals tend to become degraded. Degradation may involve loss of overall strength of the signal, and loss of definition of the pulse edges: at the time of sending, the pulse edges typically rise and fall sharply with respect to the overall pulse length giving a cleanly defined shape to the pulse whilst, at the receiver, the rate of rise and fall of the pulses tends to decrease resulting in less sharply defined pulses. In order to correct for these degradations, it is common practice to regenerate the original digital signal from the distorted one at the receiving end of a digital communication link. The regenerated signal may then be retransmitted along a further transmission link or be further processed locally.
To regenerate a received signal, typically, the receiver must ensure that the received data signal (the data signal) is processed synchronously relative to a local clock signal (the clock signal). It is also desirable to ensure that the data signal is not sampled near the degraded edges of the received data pulses which would lead to incorrect interpretation of the signal. Typically a phase locked loop would be used, containing a phase detector, an adjustable oscillator, and feedback circuit so that the receiver tends to a target clock-to-data phase relationship (the set point) which is not easily adjustable.
Alternatively in some circumstances a delay locked loop could be used, comprising a phase detector, a clock signal source, an adjustable delay in the clock or data path, and feedback circuit so that the receiver tends to a target clock-to-data phase relationship (the set point) which typically is not easily adjustable.
The target relationship may not be optimum, for example where the eye of the received data signal is asymmetrical.
It is known to make a compensating adjustment by means of one or more delays introduced into one or more paths leading from the clock signal or data signal to the phase detector or decision circuit. This has the disadvantage that it requires the delay circuitry to operate at the full speed of the clock or data signal, with associated hardware costs, power consumption, and crosstalk which can act to degrade the data or clock signal before it reaches the decision circuit and/or phase detector.
It is also known to add an offset in the phase locked or delay locked loop, for example by adding a voltage to the phase detector output, thereby directly affecting the loop feedback input signal. This has the disadvantages of being susceptible to pattern-dependent jitter, and operating only over a limited phase range.
A clock-to-data phase detector is a device which takes as two of its inputs a data signal and a clock signal and generates signals giving information about the phase difference between the data signal and clock signal. A known means of representing the phase difference information is by means of a pair of signals: the first signal (the phase difference signal) comprises a component which represents the phase difference and a further component which represents the variations in the number of edges occurring in the data; the second signal (the reference signal) represents only the latter variation. Subsequent subtraction of the reference signal from the phase signal gives a signal (the difference signal) representing the difference in phase.
It is known [from C. R. Hogge, xe2x80x9cA Self Correcting Clock Recovery Circuitxe2x80x9d, Journal of Lightwave Technology, Vol. LT-3, No. 6, December 1985] to generate a phase difference signal employing circuitry constructed using silicon components, whilst at the same time generating a reference signal by employing a fixed delay introduced by means of a delay line.
U.S. patent application Ser. Nos. 08/847,426 and 09/156,019 (Continuation-in-part) provide an improved method and apparatus for detecting the phase difference between a digital data signal and a clock signal. By ensuring that no pulse in the output phase signal is narrow enough to introduce a non-linearity, a source of non-linearity exhibited in previous known phase detectors is avoided. In addition, by ensuring that critical timing paths through the circuit contain similar circuit blocks, with similar propagation delays, relative time relationships are preserved from clock and data inputs to XOR inputs. The circuit is therefore largely insensitive to changes in the characteristics of the components so long as they all move together, as they would in an integrated circuit implementation.
U.S. Pat. No. 5,250,913 provides a phase detector for a phase locked loop for bit clock retrieval where the phase detector employs a plurality of variable unit delays and has a constant gain region that is a percentage of the clock period over an extended frequency range of the VCO enabling a single chip to operate for several applications at widely different frequencies.
The invention seeks to provide an improved method and apparatus for detecting the phase difference between a digital data signal and a clock signal.
According to a first aspect of the present invention there is provided a digital signal phase detector comprising: a data signal input for receiving a data signal; a clock signal input for receiving a clock signal; a set point control signal input for receiving a set point control signal indicative of a desired set point of the detector; a first circuit coupled to said data signal input and said clock signal input and arranged to provide a phase difference signal representative of both the clock period of the clock and the difference in phase between the clock and the data signal; a second circuit coupled to said data signal input and the clock signal input and arranged to provide a reference signal representative of the clock period of the clock signal; wherein at least one of said first and second circuits is coupled to said set point control signal and the corresponding output signal is representative of said set point control signal; and wherein a comparison of the phase difference signal with the reference signal provides an indication of the difference between the desired set point of the circuit and the phase difference between the clock and the data signal.
Advantageously, where the eye of the received signal is asymmetrical, the sampling point can be offset to the optimal sampling position.
Advantageously, whilst certain undesired delays may exist within a phase detector circuit or in circuitry leading to it, these can be compensated for.
Advantageously, the delay elements are arranged to act on regenerated digital signal pulses. The height and speed of such pulses are more predictable than those of the unregenerated data signal, and consequently the delay circuits work better.
Advantageously, the circuitry in the data and clock paths leading to the phase detector is minimised, thereby reducing power consumption, crosstalk, and improving overall performance.
Advantageously, the phase difference and reference signal pulses can be made to overlap whereby to reduce the data content to be filtered out of the error signal, thereby improving performance.
Preferably, the phase detector is arranged such that timing of pulse edges in said output signal of said at least one of said first and second circuits varies responsive to said set point control signal.
Preferably, said one of said first and second circuits comprises a first adjustable delay circuit coupled to said set point control signal, and arranged to introduce a signal delay responsive to said set point control signal, whereby to render the corresponding output signal of said one of said first and second circuits representative of said set point control signal.
Preferably, each of said first and second circuits comprises an adjustable delay circuit coupled to said set point control signal, and arranged to introduce a signal delay responsive to said set point control signal, whereby to render the output signal of each of said first and second circuits representative of said set point control signal.
Preferably, said adjustable delay circuits are arranged to introduce oppositely-varying delays responsive to said set point control signal.
Preferably, said one of said first and second circuits comprises a second adjustable delay circuit coupled to said set point control signal, and arranged to introduce a signal delay responsive to said set point control signal.
Preferably, said adjustable delay is arranged to introduce a delay of less than half of a clock cycle.
In one preferred embodiment, said adjustable delay receives a signal having pulse lengths greater than that of the input data signal.
Preferably, said adjustable delay receives a signal having a pulse length at least twice that of the input data signal.
Advantageously, delay elements may run slower than the line rate or line clock-rate: the pulse length to be delayed is typically twice the line pulse length, as opposed to the line pulse length if the data signal is delayed or half the pulse length if the clock signal is delayed.
Preferably the phase detector circuit comprises: a data-reduction circuit arranged to provide a reduced data signal which changes state upon receipt of either only rising or only falling state transitions in a digital input signal; a resynchronisation circuit arranged to provide a resynchronised reduced data signal upon receipt of a clock input signal and the reduced data signal; a first shift register circuit arranged to provide a first phase-shifted resynchronised reduced data signal upon receipt of the resynchronised reduced data signal and one or more clock signals; a second shift register circuit arranged to provide a second phase-shifted resynchronised reduced data signal upon receipt of the first phase-shifted resynchronised reduced data signal and one or more clock signals; a first Exclusive OR circuit arranged to provide a phase difference signal upon receipt of the reduced data signal and the first phase-shifted resynchronised reduced data signal; and a second Exclusive OR circuit arranged to provide a reference signal upon receipt of the resynchronised reduced data signal and the second phase-shifted resynchronised reduced data signal; an adjustable delay circuit arranged to provide a variably delayed output signal upon receipt of an input signal, responsive to a set point control signal; and wherein said adjustable delay circuit is arranged to delay one of said reduced data signal, said resynchronised reduced data signal, said first phase-shifted resynchronised reduced data signal, and said second phase-shifted resynchronised reduced data signal.
Preferably, the data-reduction circuit comprises a D-Type flip flop; the resynchronisation circuit comprises a D-Type flip flop; the first shift register circuit comprises a Latch; the second shift register circuit comprises a Latch; the first XOR circuit comprises an XOR gate; and the second XOR circuit comprises an XOR gate.
In a preferred embodiment the phase detector circuit comprises: a second adjustable delay circuit arranged to provide a variably delayed output signal upon receipt of an input signal, responsive to a set point control signal; and wherein said adjustable delay circuit and said second adjustable delay circuit are each arranged to delay a distinct one of said reduced data output signal, said resynchronised reduced data signal, said first phase-shifted resynchronised reduced data signal, and said second phase-shifted resynchronised reduced data signal.
Preferably, said adjustable delay circuit and said second adjustable delay circuits are arranged to introduce oppositely varying delays responsive to said set point control signal.
Preferably, said adjustable delay circuit is arranged to delay said reduced data signal and said second adjustable delay circuit is arranged to delay said first phase-shifted resynchronised reduced data signal.
Preferably, said first and second adjustable delay circuits are arranged to introduce oppositely varying delays responsive to said set point control signal.
According to a further aspect of the present invention there is provided a phase-locked loop circuit having a set point and comprising: a phase detector circuit according to claim 1; a loop filter and adjustable oscillator circuit arranged to provide said clock signal responsive to receipt of an output signal from said phase detector; and wherein the-set point of said phase-locked loop circuit is responsive to said set point control signal.
Preferably, said loop filter and adjustable oscillator circuit comprises: a subtractor circuit which provides a difference signal output responsive to said phase difference and reference signals; a loop filter circuit which provides a filter output signal responsive to said difference signal; an adjustable clock signal circuit which provides said clock signal responsive to said filter output signal.
According to a further aspect of the present invention there is provided a delay-locked loop data re-timing circuit comprising: a phase detector circuit according to claim 1; a decision circuit arranged to provide a re-timed data signal upon receipt of said clock signal and said data signal; and a feedback circuit arranged to receive said phase difference signal, said reference signal, and said data signal and to delay said data signal responsive to said phase difference signal and said reference signal, whereby to control the phase of said data signal prior to its delivery to said phase detector circuit and said decision circuit and to vary the set point of the phase detector.
According to a further aspect of the present invention there is provided a phase-locked loop data re-timing circuit comprising: a phase detector circuit according to claim 1; a decision circuit arranged to provide a re-timed data signal upon receipt of said clock signal and said data signal; and a feedback circuit arranged to receive said phase difference signal and said reference signal and to provide said clock signal to said phase detector circuit and said re-timing circuit responsive to said phase difference signal and said reference signal, whereby to control the phase of said clock signal prior to its delivery to said phase detector circuit and said decision circuit and to vary the set point of the phase detector.
Advantageously, the decision circuit works best if there is a time offset between the clock edges and where the actual decision point is.
Advantageously, certain undesired delays in, or leading to, the decision circuit may also be compensated for.
According to a further aspect of the present invention there is provided a system for the purposes of digital signal processing comprising a circuit according to any foregoing aspect of the present invention.
The invention is also directed to the methods by which each of the described apparatus operates and including method steps for carrying out every function of the apparatus.
According to a further aspect of the present invention there is provided a method of digital signal phase detection comprising the steps of: providing a data signal; providing a clock signal; providing a set point control signal indicative of a desired set point; providing a phase difference signal responsive to and representative of both the period of the clock signal and the difference in phase between the clock signal and the data signal; providing a reference signal responsive to and representative of the period of the clock signal; wherein at least one of said phase difference signal and reference signal is also responsive to and representative of said set point control signal; and comparing the phase difference signal with the reference signal whereby to provide an indication of the difference between the desired set point and the phase difference between the clock and the data signal.
Preferably, each of said phase difference signal and reference signal is responsive to and representative of said set point control signal.
Preferably, the signal pulse edge timing of at least one of said phase difference signal and reference signal is responsive to and representative of said set point control signal.
Preferably, timing of rising pulse edges and falling pulse edges of said at least one of said phase difference signal and reference signal varies oppositely responsive to said set point control signal.
The preferred features may be combined as appropriate, as would be apparent to a skilled person, and may be combined with any of the aspects of the invention.

Phase detector with adjustable set point


A method and system for management of thermal energy produced during transcutaneous energy transmission to provide power to energize implanted medical devices. A phase changing material (PCM) acts as a heat sink to absorb thermal energy generated during the energy transfer process. The PCM can be thermally coupled to tissue proximate to an implanted medical device, enabling heat generated within the implantable device to be absorbed. The generation of heat during the energy transfer process is primarily caused by eddy currents induced in the implantable device by the magnetic flux produced by the energy transfer system. The PCM can also be used to absorb heat generated by the device producing the magnetic flux that is used to transcutaneously transfer electrical power to recharge a rechargeable power source or energize the implanted medical device.

Many types of implantable medical devices require a source of electrical energy. For example, pacemakers, defibrillators, drug infusion pumps, cochlear implants, and brain activity monitoring/stimulation systems all require a power source. Many of these implantable medical devices provide therapy and/or diagnostic functions, and have significant electrical power requirements.
Electrical current used to supply the electrical power required by an implanted medical device can be conveyed through an electrical lead that is connected to the device and extends outside the patient's body for connection to an external power source. However, a transcutaneous lead that passes through the skin increases the risk of infection when left in place for an extended period. Implanted medical devices may also be powered by a non-rechargeable battery. However, replacement of such a battery subjects the patient to further surgery, and thus, may not be desirable, particularly if replacement is frequently necessary.
As an alternative to a non-rechargeable battery, an implanted rechargeable battery can be recharged by transcutaneously coupling power from an external source to an implanted receiver that is connected to the rechargeable battery. One of the more efficient recharging techniques employs an external transmission coil and an internal receiver coil, which are inductively coupled so that power can be conveyed from the transmission coil to the receiver coil. In this transcutaneous energy transmission (TET) approach, the external primary transmission coil is energized with alternating current (AC), producing a time varying magnetic field that passes through the patient's skin and induces a corresponding AC in the internal secondary receiving coil. The voltage induced in the receiving coil may then be rectified to provide direct current (DC) that is used to power the implanted medical device and/or charge a battery or other charge storage device (e.g., an ultra capacitor), which continues to energize the implanted medical device after the inductive supply of electrical power is terminated. This transcutaneous energy transmission work was originally pioneered by J. C. Schuder in 1961 (J. C. Schuder, H. E. Stephenson, and J. F. Townsend, "High level electromagnetic energy transfer through a closed chest wall," IRE International Convention Record 9, part 9, pp. 119-126, 1961).
One challenge in designing TET systems is that eddy currents are induced in the metallic components (such as the housing or printed circuit boards) of the implanted medical device. Such eddy currents can produce a generally undesirable temperature increase or heating of the implantable device. The amount of heat generated is generally a function of the amplitude and frequency of the magnetic flux used in the TET system.
Additional thermal challenges presented in TET systems are caused by the heat produced within the external transmission coil and its associated external enclosure. One problem is that temperature increases in the external transmission coil decreases the efficiency of the TET system. For example, heating of the primary coil increases the resistance of the windings, which serves to reduce the amount of power transferred to the implantable unit, thereby increasing the time required for recharging, resulting in further heating of the external transmission coil enclosure and the heating of the implanted medical device. A second problem is that as the external transmission coil heats up, such heat can be transferred to the external housing surrounding the coil. That housing is located proximal to the patient's skin nearest the implanted medical device, and such a temperature increase can increase the skin temperature.
Implanted medical devices are generally surrounded by tissue, which to a certain extent will conduct heat away from the device. However, implanted device temperatures exceeding safe thresholds may injure or permanently damage surrounding tissue. The ability of human tissue to withstand hyperthermic conditions is governed by a complex relationship of factors including tissue type, temperature, and exposure time. It would be desirable to provide a method and apparatus that reduces the risk of damaging adjacent tissue during the recharging of implanted medical devices when using TET. Furthermore, the amount of transmitted power is primarily limited by the heating of (i) the tissue surrounding the implanted device; (ii) the skin surface adjacent to the external charging device; and (iii) the temperature of the external charging device. Such aforementioned heating limits the amount of power that may be transferred by the TET system, which increases the time required for recharging. Since the patient is typically inconvenienced during the recharging period, it would be desirable to maximize the power rate of transfer while minimizing associated heating. Prospective techniques for accomplishing that may employ one or more of the following strategies: (1) minimizing the heat caused by induced eddy currents; (2) transferring heat away from the tissue surrounding the implantable medical device; (3) reducing the operating temperature of the external components of the TET system; and, (4) isolating any temperature elevation of the external components of the TET system from the tissue proximate the implanted medical device.

Phase change material as a dynamic heat sink for trancutaneous energy transmission systems


There is disclosed a lightweight and small liquid crystal display which achieves low power consumption and in which the optical anisotropy of the liquid crystal material is compensated for in order to enhance the viewing angle characteristics and the response speed of the liquid crystal material. Display electrodes and a common electrode are formed on one of the substrates. The orientation of the liquid crystal material is of the HAN (hybrid alignment nematic) type. This compensates for the optical anisotropy of the liquid crystal material and improves the response speed.

Since liquid crystal displays are lighter and more compact display devices than CRTs, they find extensive application in computers, electronic calculators, clocks, and watches. The principle of operation of liquid crystal displays depends on a change in an optical property, such as interference, scattering, diffraction, optical rotation, or absorption, of a liquid crystal material. This change is caused by a variation in orientation of the liquid crystal molecules or a phase transition in response to application of an external field such as electric field or heat.
Generally, a liquid crystal display comprises a pair of substrates with a given spacing which is maintained at 1 to tens of micrometers. A liquid crystal material is held between these substrates, thus forming a liquid crystal panel. At least one of the substrates has transparency. Electrodes are formed on both or one of the substrates. Using these electrodes, an electric field is applied to the liquid crystal material to control the orientation of the liquid crystal molecules in each different pixel within the substrate plane, thus controlling the amount of light transmitted through the liquid crystal panel. In this way, a desired image is displayed. The liquid crystal display is constructed differently according to which is the above-described optical properties is utilized, i.e., depending on the mode of operation. For example, polarizing plates are mounted on the Outside of the liquid crystal panel.
To date, twisted-nematic (TN) liquid crystal displays and supertwisted-nematic (STN) liquid crystal displays enjoy wide acceptance. These kinds of liquid crystal displays make use of optical properties of liquid crystal materials such as optical rotation and interference of birefringent light. Both kinds require polarizing plates.
Where an image is displayed by the above-described liquid crystal display, numerous pixels must be controlled at the same time. For this purpose, various methods have been proposed. Among them, active matrix driving is used widely because it is a method capable of displaying image with high information content and high image quality. In particular, nonlinear active devices such as diodes or transistors are arranged at pixels. The individual pixels are electrically isolated from each other. Interference with unwanted signals is prevented. Thus, high image quality is accomplished. In this method, each pixel can be regarded as a capacitor to which an electrical switch is connected. Accordingly, the switches are turned on and off according to the need. As a result, electric charge can be made to go into and out of the pixels. If the switches are turned off, electric charge can be retained in the pixels and so the pixels can retain memory.

Liquid crystal display and method of driving same

Semiconductor Energy Laboratory Co., Ltd.


A parts cleaning device has at least one rotor assembly with an axis of rotation, and a plurality of microfiber cloths arranged at spaced locations along a length of each rotor assembly. The microfiber cloths each have an opening through a center portion thereof, and a shaft of the rotor assembly extends through the opening. A plurality of spacers are arranged so that each microfiber cloth is squeezed between two spacers. The rotor assembly is rotated together with the microfiber cloths so that centrifugal forces cause the microfiber cloths to extend radially outwardly from the rotor assembly and wipe surfaces of parts that pass within a path of movement of the microfiber cloths. A vacuum chamber has an inlet positioned in the path of movement of the cloths for removing fine particles from the cloths as the cloths rotate past the inlet.

1. Field of the Invention
The present invention relates generally to devices and methods for removing fine particles from parts during a manufacturing process, and in particular, to devices and methods for wiping fine particles from a surface of a part.
2. Description of the Related Art
Processes for manufacturing cabinets, furniture and other wood products typically include a series of smoothing and finishing steps. For example, at least one and often several sanding and buffing steps are typically used to smooth and prepare a wood surface to receive sealants, stains, varnishes, and other surface coatings. Additional sanding or buffing steps are also typically used between surface coatings to prepare the surface for each new coating.
Sanding and buffing creates fine particles that must be removed from the wood surface or coated surface before a finish coating is applied to the surface. This is typically accomplished by manually wiping the part using tack rags, cheese cloth, or the like. However, such manual wiping is labor intensive and often creates a bottleneck that limits the efficiency of a manufacturing process.
A power driven duster using ostrich feathers has been used to remove dust from wood surfaces. However, the ostrich feathers of the duster were expensive and relatively fragile, requiring frequent maintenance and high operating costs.
There is a need in the industry for an improved device and method for removing fine particles from wood surfaces and other parts during a manufacturing process.

Device and method for removing fine particles from parts


A linear actuator having a housing, a plunger slidably mounted to the housing between an extended and retracted position, and an electric motor drivingly connected to the plunger to move the plunger between its extended and retracted positions. A motor circuit controls the activation of the motor circuit and deactivates the motor circuit whenever the motor current exceeds a threshold value which varies as a function of the supply voltage to the electric motor and/or temperature. A memory storage unit stores the position of the plunger. Whenever the position of the plunger is in a state of transition between its retracted and extended position upon system initialization, the motor control circuit activates the motor to drive the plunger to a preselected extended or retracted position.

I. Field of the Invention
The present invention relates generally to linear actuators and, more particularly, to an electric motor driven linear actuator.
II. Description of Relevant Prior Art
There are many previously known linear actuators that are powered with electric motors. These previously known linear actuators typically comprise a housing having a plunger slidably mounted to the housing and movable between an extended and a retracted position. An electric motor is drivingly connected to the plunger to move the plunger between its extended and its retracted position in response to activation of the motor.
In many situations, it is desirable to move the linear actuator between preselected extended and retracted positions. In order to selectively deactivate the motor whenever the plunger reaches its retracted or extended position, these previously known linear actuators have typically employed limit switches which are activated by the plunger whenever the plunger is in its extended or retracted position.
These previously known linear actuators with limit switches, however, have not proven entirely satisfactory in use. One disadvantage of these previously known linear actuators with limit switches is that they oftentimes fail after extended and repeated use. When this occurs, the limit switch no longer deactivates the motor when the plunger reaches either its extended or retracted position in the desired fashion.
A still further disadvantage of these previously known linear actuators with limit switches is that the limit switches increase the overall cost of the linear actuator.
A still further disadvantage of these previously known linear actuators is that it is oftentimes desirable upon system initialization to determine if the linear actuator was in its extended position, its retracted position or a transition position in between the extended and retracted positions at system startup. For example, in the automotive industry such linear actuators are used, inter alia, to control the shift between a four-wheel and two-wheel drive transmission of an automotive vehicle. In the event that the linear actuator was in its retracted position or extended position at system startup, it would be normally desirable to leave the linear actuator in that position. Consequently, if an automotive vehicle was in the four-wheel transmission mode at engine startup, it would normally be desirable to simply leave the vehicle in the four-wheel transmission mode, or vice versa.
Conversely, if the linear actuator was in a state of transition between its extended and retracted positions upon engine startup or system initialization, it would be desirable to actuate the linear actuator to move to a preselected one of its extended and retracted positions on system initialization rather than leave the linear actuator in a transition position. The previously known linear actuators, however, fail to account for the condition where the linear actuator was in an intermediate position at the time of the last system shutdown and thus at the time of the next system initialization. Unless corrected upon system initialization, the partially actuated linear actuator may create unpredictable and undesirable results.