A communication device for providing a channel state information, CSI, feedback in a wireless communication system includes a transceiver to receive a radio signal including downlink reference signals. The processor                estimates an explicit CSI,        selects a Doppler-delay precoder matrix for a composite Doppler-delay-beam three-stage precoder,        calculates and reports to the transmitter a CSI feedback.

FIG. 1 is a schematic representation of an example of a terrestrial wireless network 100 including a core network 102 and a radio access network 104. The radio access network 104 may include a plurality of base stations gNB1 to gNB5, each serving a specific area surrounding the base station schematically represented by respective cells 1061 to 1065. The base stations are provided to serve users within a cell. The term base station, BS, refers to as gNB in 5G networks, eNB in UMTS/LTE/LTE-A/LTE-A Pro, or just BS in other mobile communication standards. A user may be a stationary device or a mobile device. Further, the wireless communication system may be accessed by mobile or stationary IoT devices which connect to a base station or to a user. The mobile devices or the IoT devices may include physical devices, ground based vehicles, such as robots or cars, aerial vehicles, such as manned or unmanned aerial vehicles (UAVs), the latter also referred to as drones, buildings and other items or devices having embedded therein electronics, software, sensors, actuators, or the like as well as network connectivity that enable these devices to collect and exchange data across an existing network infrastructure. FIG. 1 shows an exemplary view of only five cells, however, the wireless communication system may include more such cells. FIG. 1 shows two users UE1 and UE2, also referred to as user equipment, UE, that are in cell 1062 and that are served by base station gNB2. Another user UE3 is shown in cell 1064 which is served by base station gNB4. The arrows 1081, 1082 and 1083 schematically represent uplink/downlink connections for transmitting data from a user UE1, UE2 and UE3 to the base stations gNB2, gNB4 or for transmitting data from the base stations gNB2, gNB4 to the users UE1, UE2, UE3. Further, FIG. 1 shows two IoT devices 1101 and 1102 in cell 1064, which may be stationary or mobile devices. The IoT device 1101 accesses the wireless communication system via the base station gNB4 to receive and transmit data as schematically represented by arrow 1121. The IoT device 1102 accesses the wireless communication system via the user UE3 as is schematically represented by arrow 1122. The respective base station gNB1 to gNB5 may be connected to the core network 102, e.g. via the S1 interface, via respective backhaul links 1141 to 1145, which are schematically represented in FIG. 1 by the arrows pointing to "core". The core network 102 may be connected to one or more external networks. Further, some or all of the respective base station gNB1 to gNB5 may connected, e.g. via the S1 or X2 interface or XN interface in NR, with each other via respective backhaul links 1161 to 1165, which are schematically represented in FIG. 1 by the arrows pointing to "gNBs". The wireless network or communication system depicted in FIG. 1 may by an heterogeneous network having two distinct overlaid networks, a network of macro cells with each macro cell including a macro base station, like base station gNB1 to gNB5, and a network of small cell base stations (not shown in FIG. 1), like femto or pico base stations.
For data transmission a physical resource grid may be used. The physical resource grid may comprise a set of resource elements to which various physical channels and physical signals are mapped. For example, the physical channels may include the physical downlink and uplink shared channels (PDSCH, PUSCH) carrying user specific data, also referred to as downlink and uplink payload data, the physical broadcast channel (PBCH) carrying for example a master information block (MIB) and a system information block (SIB), the physical downlink and uplink control channels (PDCCH, PUCCH) carrying for example the downlink control information (DCI), etc. For the uplink, the physical channels may further include the physical random access channel (PRACH or RACH) used by UEs for accessing the network once a UE synchronized and obtained the MIB and SIB. The physical signals may comprise reference signals or symbols (RS), synchronization signals and the like. The resource grid may comprise a frame or radio frame having a certain duration, like 10 milliseconds, in the time domain and having a given bandwidth in the frequency domain. The frame may have a certain number of subframes of a predefined length, e.g., 2 subframes with a length of 1 millisecond. Each subframe may include two slots of 6 or 7 OFDM symbols depending on the cyclic prefix (CP) length. A frame may also consist of a smaller number of OFDM symbols, e.g. when utilizing shortened transmission time intervals (sTTI) or a mini-slot/non-slot-based frame structure comprising just a few OFDM symbols.
The wireless communication system may be any single-tone or multicarrier system using frequency-division multiplexing, like the orthogonal frequency-division multiplexing (OFDM) system, the orthogonal frequency-division multiple access (OFDMA) system, or any other IFFT-based signal with or without CP, e.g. DFT-s-OFDM. Other waveforms, like non-orthogonal waveforms for multiple access, e.g. filter-bank multicarrier (FBMC), generalized frequency division multiplexing (GFDM) or universal filtered multi carrier (UFMC), may be used. The wireless communication system may operate, e.g., in accordance with the LTE-Advanced pro standard or the 5G or NR, New Radio, standard.
In the wireless communication network as shown in FIG. 1 the radio access network 104 may be a heterogeneous network including a network of primary cells, each including a primary base station, also referred to as a macro base station. Further, a plurality of secondary base stations, also referred to as small cell base stations, may be provided for each of the macro cells. In addition to the above described terrestrial wireless network also non-terrestrial wireless communication networks exist including spaceborne transceivers, like satellites, and/or airborne transceivers, like unmanned aircraft systems. The non-terrestrial wireless communication network or system may operate in a similar way as the terrestrial system described above with reference to FIG. 1, for example in accordance with the LTE-advanced pro standard or the 5G or NR, new radio, standard.
In a wireless communication system like to one depicted schematically in FIG. 1, multi-antenna techniques may be used, e.g., in accordance with LTE or NR, to improve user data rates, link reliability, cell coverage and network capacity. To support multi-stream or multi-layer transmissions, linear precoding is used in the physical layer of the communication system. Linear precoding is performed by a precoder matrix which maps layers of data to antenna ports. The precoding may be seen as a generalization of beamforming, which is a technique to spatially direct/focus data transmission towards an intended receiver. The precoder matrix to be used at the gNB to map the data to the transmit antenna ports is decided using channel state information, CSI.
In a communication system as described above, such as LTE or New Radio (5G), downlink signals convey data signals, control signals containing down link, DL, control information (DCI), and a number of reference signals or symbols (RS) used for different purposes. A gNodeB (or gNB or base station) transmits data and control information (DCI) through the so-called physical downlink shared channel (PDSCH) and physical downlink control channel (PDCCH) or enhanced PDCCH (ePDCCH), respectively. Moreover, the downlink signal(s) of the gNB may contain one or multiple types of RSs including a common RS (CRS) in LTE, a channel state information RS (CSI-RS), a demodulation RS (DM-RS), and a phase tracking RS (PT-RS). The CRS is transmitted over a DL system bandwidth part, and used at the user equipment (UE) to obtain a channel estimate to demodulate the data or control information. The CSI-RS is transmitted with a reduced density in the time and frequency domain compared to CRS, and used at the UE for channel estimation/channel state information (CSI) acquisition. The DM-RS is transmitted only in a bandwidth part of the respective PDSCH and used by the UE for data demodulation. For signal precoding at the gNB, several CSI-RS reporting mechanism were introduced such as non-precoded CSI-RS and beamformed CSI-RS reporting (see reference [1]). For a non-precoded CSI-RS, a one-to-one mapping between a CSI-RS port and a transceiver unit, TXRU, of the antenna array at the gNB is utilized. Therefore, non-precoded CSI-RS provides a cell-wide coverage where the different CSI-RS ports have the same beam-direction and beam-width. For beamformed/precoded UE-specific or non-UE-specific CSI-RS, a beam-forming operation is applied over a single- or multiple antenna ports to have several narrow beams with high gain in different directions and therefore, no cell-wide coverage.
In a wireless communication system employing time division duplexing, TDD, due to channel reciprocity, the channel state information (CSI) is available at the base station (gNB). However, when employing frequency division duplexing, FDD, due to the absence of channel reciprocity, the channel has to be estimated at the UE and feed back to the gNB. FIG. 2 shows a block-based model of a MIMO DL transmission using codebook-based-precoding in accordance with LTE release 8. FIG. 2 shows schematically the base station 200, gNB, the user equipment, UE, 202 and the channel 204, like a radio channel for a wireless data communication between the base station 200 and the user equipment 202. The base station includes an antenna array ANTT having a plurality of antennas or antenna elements, and a precoder 206 receiving a data vector 208 and a precoder matrix F from a codebook 210. The channel 204 may be described by the channel tensor/matrix 212. The user equipment 202 receives the data vector 214 via an antenna or an antenna array ANTR having a plurality of antennas or antenna elements. A feedback channel 216 between the user equipment 202 and the base station 200 is provided for transmitting feedback information. The previous releases of 3GPP up to Rel.15 support the use of several downlink reference symbols (such as CSI-RS) for CSI estimation at the UE. In FDD systems (up to Rel. 15), the estimated channel at the UE is reported to the gNB implicitly where the CSI transmitted by the UE over the feedback channel includes the rank index (RI), the precoding matrix index (PMI) and the channel quality index (CQI) (and the CRI from Rel. 13) allowing, at the gNB, deciding the precoding matrix, and the modulation order and coding scheme (MCS) of the symbols to be transmitted. The PMI and the RI are used to determine the precoding matrix from a predefined set of matrices a called 'codebook'. The codebook, e.g., in accordance with LTE, may be a look-up table with matrices in each entry of the table, and the PMI and RI from the UE decide from which row and column of the table the precoder matrix to be used is obtained. The precoders and codebooks are designed up to Rel. 15 for gNBs equipped with one-dimensional Uniform Linear Arrays (ULAs) having N1 dual-polarized antennas (in total Nt=2N1 antennas), or with two-dimensional Uniform Planar Arrays (UPAs) having dual-polarized antennas at N1N2 positions (in total Nt=2N1N2 antennas). The ULA allows controlling the radio wave in the horizontal (azimuth) direction only, so that azimuth-only beamforming at the gNB is possible, whereas the UPA supports transmit beamforming on both vertical (elevation) and horizontal (azimuth) directions, which is also referred to as full-dimension (FD) MIMO. The codebook, e.g., in the case of massive antenna arrays such as FD-MIMO, may be a set of beamforming weights that forms spatially separated electromagnetic transmit/receive beams using the array response vectors of the array. The beamforming weights (also referred to as the 'array steering vectors') of the array are amplitude gains and phase adjustments that are applied to the signal fed to the antennas (or the signal received from the antennas) to transmit (or obtain) a radiation towards (or from) a particular direction. The components of the precoder matrix are obtained from the codebook, and the PMI and the RI are used to 'read' the codebook and obtain the precoder. The array steering vectors may be described by the columns of a 2D Discrete Fourier Transform (DFT) matrix when ULAs or UPAs are used for signal transmission.
The precoder matrices used in the Type-I and Type-II CSI reporting schemes in 3GPP New Radio Rel. 15 are defined in frequency-domain and have a dual-stage structure: F(s)=F1F2(s), s=0 . . . , S−1 (see reference [2]), where S denotes the number of subbands. The matrix F1 is a wide-band matrix, independent on index s, and contains U spatial beamforming vectors (the so-called spatial beams) bu∈N1N2×1, u=1, . . . , U selected out of a DFT-codebook matrix,
      F    1    =            [                                                                  b                1                            ,              …                                                                        ,                              b                U                                                                        0                                                                                …                                                                                0                                                                          0                                                                                …                                                                                0                                                                          b                1                            ,              …                                                                        ,                              b                U                                                        ]        ∈                                    2                                N            1                                          N            2                    ×          2                    U                    .
The matrix F2(s), is a selection/combining/co-phasing matrix that selects/combines/co-phases the beams defined in F1 for the s-th configured sub-band.
For example, for a rank-1 transmission and Type-I CSI reporting, F2(s) is given for a dual-polarized antenna array by [2]
                    F        2                          (        s        )              =                  [                                                            e                u                                                                                e                                      j                                                              δ                      1                                                                                e                  u                                                                    ]            ∈                                2                    U          ×          1                      ,
where eu∈U×1, u=1, 2, . . . , U contains zeros at all positions, except the u-th position which is one. Such a definition of eu selects the u-th vector for each polarization of the antenna array, and combines them across both polarizations. Furthermore, δ1 is a quantized phase adjustment for the second polarization of the antenna array.
For example, for a rank-1 transmission and Type-II CSI reporting, F2(s) is given for dual-polarized antenna arrays by [2]
            F      2                  (      s      )        =            [                                                                  e                                  j                                                        δ                    1                                                                                p                1                                                                          ⋮                                                                              e                                  j                                                        δ                                          2                                            U                                                                                p                                  2                                    U                                                                        ]        ∈                                  U          ·          2                ×        1
where pu and δu, u=1, 2, . . . , 2U are quantized amplitude and phase beam-combining coefficients, respectively.
For rank-R transmission, F2(s) contains R vectors, where the entries of each vector are chosen to combine single or multiple beams within each polarization and/or combining them across both polarizations.
The selection of the matrices F1 and F2(s) is performed by the UE based on the knowledge of the current channel conditions. The selected matrices are contained in the CSI report in the form of a RI and a PMI and used at the gNB to update the multi-user precoder for the next transmission time interval.
An inherent drawback of the current CSI reporting formats described in [2] for the implicit feedback scheme is that the RI and PMI only contain information of the current channel conditions. Consequently, the CSI reporting rate is related to the channel coherence time which defines the time duration over which the channel is considered to be not varying. This means, in quasi-static channel scenarios, where the UE does not move or moves slowly, the channel coherence time is large and the CSI needs to be less frequently updated. However, if the channel conditions change fast, for example due to a high movement of the UE in a multi-path channel environment, the channel coherence time is short and the transmit signals experience severe fading caused by a Doppler-frequency spread. For such channel conditions, the CSI needs to be updated frequently which causes a high feedback overhead. Especially, for future NR systems (Rel. 16) that are likely to be more multi-user centric, the multiple CSI reports from users in highly-dynamic channel scenarios will drastically reduce the overall efficiency of the communication system.
To overcome this problem, several explicit CSI feedback schemes have been proposed that take into account the channel-evolution over time (see reference [3]). Here, explicit CSI refers to reporting of explicit channel coefficients from the UE to the gNB without a codebook for the precoder selection at the UE. Those schemes have in common estimating the parameters of the dominant channel taps of the multipath propagation channel as well as their time-evolution at the UE. For example, in [3] each channel tap is modelled as a sum of sub-channel taps where each sub-tap is parameterized with a Doppler-frequency shift and path gain. The estimated parameters for each channel tap are fed back to the base station, where they are used with a channel model for time-domain based channel prediction before downlink precoding. The availability of explicit CSI comes at an increased overhead for the feedback channel compared to implicit-based channel feedback, especially for slow-varying channels, which is not desired.
For example, WO 2018/052255 A1 relates to explicit CSI acquisition to represent the channel in wireless communication systems using the principle component analysis (PCA), which is applied on the frequency-domain channel matrix, covariance matrix, or eigenvector of the channel matrix. Thus, a codebook approach for downlink signal precoding at the base station equipped with a two-dimensional array and CSI reporting configuration is proposed. However, an inherent drawback of the proposed CSI reporting scheme is that the CSI report from a user contains only information about the selected CQI, PMI and RI with respect to the current MIMO channel state/realization and does not take into account channel variations over time caused by small-scale channel fading. Therefore, when users experience fast-fading channel conditions, a frequent CSI update is needed which causes a high feedback overhead over time. Moreover, the proposed CSI reporting scheme is restricted to one beam per layer PMI feedback which leads to a limited CSI accuracy and turns out to be insufficient for CSI acquisition in multi-user MIMO.
Moreover, to track channel-evolution over time, the reference signal need be spread over time. In the current 3GPP NR specification [1], a single shot CSI-RS is configured at a particular time slot. Such slots of CSI-RS are periodically transmitted, or triggered on demand. The configuration of a CSI-RS resource set(s) which may refer to NZP-CSI-RS, CSI-IM or CSI-SSB resource set(s) [2] is performed using the following higher layer parameters (see reference [4]):                CSI-ResourceConfig—The resource set(s) configuration consists of the IDs of the resources configured in the resource set(s), the type of each CSI-RS resource in terms of its periodicity, and the bandwidth part they are configured in.        CSI-ResourcePeriodicityAndOffset—Mentions the periodicity of a CSI-RS resource in terms of number of slots and offset of CSI-RS.        CSI-RS-ResourceMapping—Mentions the resource elements in the time-frequency map the CSI-RS resource is mapped to, number of CSI-RS ports, the CDM type used for the mapped reference symbols, and the density and bandwidth of occupancy of the reference symbols in the frequency domain.                    frequencyDomainAllocation            nrofPorts            firstOFDMSymbolInTimeDomain            firstOFDMSymbolInTimeDomain2            cdm-Type            density            freqBand
While the CSI-RS design may be used to acquire CSI for a link adaptation (modulation and coding scheme—MCS), and for selecting a precoding matrix from a specific channel realization/snapshot, it cannot track channel evolution in time to estimate Doppler-frequency components of a MIMO channel.
It is noted that the information in the above section is only for enhancing the understanding of the background of the invention and therefore it may contain information does not form known technology that is already known to a person of ordinary skill in the art.

CSI reporting and codebook structure for doppler-delay codebook-based precoding in a wireless communications system

Abstract: The communication device selects from one or more codebooks a subset of D delay components and/or a subset of F Doppler-frequency components and uses the selected subset of delay components for each polarization and each spatial beam and/or the selected subset of Doppler-frequency components for each polarization, each spatial beam and each delay, when calculating the Doppler-delay precoder matrix.


A liquid crystal display (LCD) has a plurality of pixels, each having an aperture region. A LCD display element includes a shorting metal formed outside of the pixel aperture region for converting defective pixels into black defects. The shorting metal is formed from the same material used in, and during the same manufacturing step of, forming the TFT gate electrode. Therefore, the pixel aperture ratio is not reduced and subsequent steps to form the shorting metal are unnecessary.

1. Field of the Invention
The present invention relates to a liquid crystal display element and a manufacturing method therefor. More particularly, the present invention relates to a liquid crystal display element and manufacturing method in which shorting metal for treating defective pixels is formed outside the pixel aperture region during fabrication of the display element.
2. Description of the Related Art
Active matrix liquid crystal displays (LCDs) typically operate in a white mode. When individual display pixels become defective, as shown in FIG. 1, a laser welding technique is used to connect a shorting metal 28 between a pixel electrode 15 and a source line 19 in order to convert the defective pixel into a black defect (otherwise referred to as a dark defect). However, this conventional technique has some disadvantages, some of which are described below.
First, the aperture ratio of the aperture region is reduced because the shorting metal 28 is formed partially within the pixel electrode. Further, because the shorting metal 28 is at a floating potential, parasitic capacitance develops between the pixel electrode 15 and the source line 19. This in turn degrades picture quality.
In another conventional technique shown in FIG. 2, a pixel electrode 151 is electrically connected with a source line 191 using a shorting metal. In this thin film transistor (TFT), a gate electrode 251 extends outward from the gate line 181. A defective pixel is transformed into a black defect by disconnecting the gate electrode 251 from a gate line 181 (shown by gap 182) using a laser, for example. However, this technique has several problems as well.
First, when the gate electrode 251 is formed on the gate line 181 as shown in FIG. 2, to extend a pixel aperture ratio, it is difficult for this technique to be adapted unless the gate line 181 consists of two lines. Moreover, even if the gate line 181 consists of two lines, when the gap 182 is insufficient to disconnect the gate electrode 251 from the gate line 181, this technique can't be adapted.

Liquid crystal display element and manufacturing method thereof


A method of rendering at least part of an image from an at least one external source into a two-dimensional memory array having integer x and y pixel coordinates based upon a set of integer coordinates of an outline of the rendered image. The method includes the steps of forming a parallelogram defined by a parallel series of effect lines forming an angle e with either the x or y axis of the memory array and bounded on opposing ends of the scan lines by a scan axis, the parallelogram surrounding at least part of the two-dimensional memory array and rendering the image from the at least one external source into the memory array while moving unidirectionally along the effect lines and scan axis using the outline coordinates as transition points for selection and non-selection of the image.

Video special effects of changing from a first video image "A" to a second video image "B" are generally known. Examples that are generally known include page rolling and page turning.
In page turning, a corner of the first image is generally shown to lift and fold over, thereby exposing a second image. The corner is then moved diagonally across the first image thereby exposing larger and larger portions of the second image. As the corner of the first image lifts and is folded-over the area of the front side near the fold becomes distorted and, a backside of the lifted corner is displayed as a reversed portion of the first image, which lifted corner then continues to fold over as it moves across the first image covering larger and larger portions of the first image as the first image is completely replaced by the second image.
In page rolling, a corner (or even a whole side) of the first image is seen to lift and roll across the screen covering the first image and exposing the second image. A reversed backside of the first image is displayed as a rolling cylinder which rolls over the first image.
Alternatively, the first image will be seen to form parallel waves across the screen with the first image following the peaks and valleys of the waves. The waves of the first image may then be swept off the screen from one side to the other as the first image is replaced by the second image.
Often the parallel waves will be seen to slope from left to right or right to left forming an angle of .theta. with the x or y axis along an effect axis when viewed from the bottom to the top of the screen. Where the peaks of the waves of the first image appear at the bottom of the screen, portions of the second image will become visible below the wave peaks of the first image.
Similarly when page turning is used, the first image, on the page being turned, is typically made to appear distorted where the corner of the first image is lifted to turn the page. The distorted area of the first image follows the folded-over corner of the first image as the page is turned to reveal the second image.
A number of known processes are available for providing page turning video effects. One known technique requires a complicated vector analysis process to track a turned edge of the first image. A vector origin that may or may not coincide with a corner of the image is first determined. A coordinate system corresponding with the turned edge of the image is then imposed on the page turning process. The results of the vector analysis is then used to access data for forming the image within non-linear portions of the turned page.
Such techniques require a double buffer for storing video information. The first buffer stores the prior image while the second buffer stores the page turning graphics generated through vector processing. A video switch is then used to switch between the second buffer providing the graphics for the first image and the buffer providing the second image.
While prior art techniques are effective in creating the complicated graphics associated with page turning and the like, the process of generating such graphics is computationally intensive. The computational intensity and complexity of such processing also limits the flexibility of such systems.
Other examples of a page turning video graphics divide the video screen into a number of different boundary areas divided by a number (e.g., three) of parabolic boundary lines and one straight boundary line. The locations of the boundary lines are determined by solving four equations. To simplify the computational complexity, a processor first identifies intersection points of the boundary lines for each step of the page turning process and then calculates a parabolic and linear position for the boundary lines. A video switch then switches from a first to a second video image, from the first video image to a blank image (backside of the first video image), or from the blank image to the second video image based upon which boundary line is crossed.
Conventional rendering techniques, such as described above, generate page turning effects by splitting the rectangular image into several portions: a) previous image; b) distorted previous image; c) distorted reverse side of previous image; and d) next image. The boundaries between the portions may be defined by circles, lines, or parabolas.
Conventional methods and apparatus create the effect of geometrical distortions by using circular or parabolic mapping processes. However, visual observations of a person actually turning a page reveal that such circular-shaped boundaries do not provide an accurate rendition of page turning. Also, since the special effect of the geometrical distorted portion is created one horizontal scan line at a time, the creation of a high quality special effect image involving geometrical distortion is inherently computationally intensive.
Conventional methods also typically process the video signals real-time. Since real-time video signals (NTSC and PAL broadcast standards) provide one scan line at a time, the conventional method must render one horizontal scan line at a time to keep up with the real-time video source. If non-horizontal rendering is used, frequently there are gaps in the rendered portions of an image (i.e., not all pixels in the rendered area are guaranteed to be rendered).
While the known processing systems perform adequately, such systems do not make efficient use of video processing resources. Conventional rendering techniques either perform complex calculations to obtain needed high quality video images or completely avoid the complex calculations at the expense of providing a lesser quality image. Because of the importance of video processing, a need exists for a means of rendering video imaging special effects that is less computationally intensive.

Method and apparatus of rendering a video image


A first merchant node on a semi-private blockchain virtual currency exchange system is exclusively capable of creating first virtual currency units. Unaffiliated merchant node(s) are exclusively capable of creating other merchant-specific virtual currency units in the system, while customer computing devices are incapable of creating virtual currency units. The first merchant node creates and issues first virtual currency units to a first customer account associated with a first customer computing device. Upon receiving a transaction request for exchanging first virtual currency unit(s) for a second currency type between the first customer account and another customer account, the first merchant node validates the first transaction request, and creates and sends a first transaction receipt to unaffiliated merchant node(s). Upon receiving a redemption request from a customer account, the first merchant node validates the first redemption request, and creates and sends a first redemption receipt to unaffiliated merchant node(s).

Merchants often provide rewards points, discounts, promotions, etc. to customers in order to incentivize customers to return for repeat purchases (e.g., buying five cups of coffee to receive a free sixth cup). These rewards may be attractive to "regular" customers who frequently patron a particular merchant but are less effective for those who only make infrequent visits. Often, customers obtain rewards from a merchant that they are unlikely to redeem (e.g., because they live in an area that lacks a physical store for that merchant, they prefer another merchant, they do not need a particular volume of a product, etc.) and are unable to benefit from the rewards by exchanging the reward with another customer who would like to redeem it.
Some merchants (e.g., credit card issuers, airlines, etc.) allow customers to exchange one type of their rewards points for another type of their rewards points or rewards points for an affiliated partner (e.g., credit card points in exchange for air mileage points with an affiliated partner, air mileage points in exchange for those of an affiliated partner airline, etc.), but such exchanges are limited to certain types of rewards points and partnerships between merchants, both of which are determined by the merchants. Instead, many customers may prefer to exchange rewards points for those affiliated with any merchant of their choosing, regardless of merchant partnerships or type of rewards points. Other existing Internet-based marketplaces allow customers to exchange rewards points for cash or freely barter any property, but typically either charge a substantial fee to facilitate the exchange for cash or are unregulated and present security and authenticity risks.
To more freely and securely facilitate transactions and exchanges involving rewards points, some systems have turned to so-called distributed "blockchain" systems that can simultaneously record transaction-related entries in multiple places, and simultaneously. Unlike traditional centralized ledgers, which typically rely on a central authority to validate the authenticity of transactions recorded in the database and make the system susceptible to lost information, tampering, validation delays, etc., such blockchain systems typically have no centralized data store. Instead, transactions are bundled into blocks that are chained together and then broadcasted to other nodes in the network. Different types of blockchain systems restrict who is allowed to particulate in the system and maintain the shared ledger. For example, public blockchain systems (e.g., Bitcoin) have no participant restrictions but typically require substantial computational power to maintain a ledger on a large scale and provide little privacy and security. Conversely, private and semi-private blockchain systems restrict what entities are authorized to participate in writing to the distributed ledger. While helpful, existing blockchain systems struggle to provide appropriate control and flexibility in a manner that provides widespread access to customers and merchants wishing to participate, ensures the authenticity of rewards points, securely and cost-efficiently facilitates transactions, and avoids overloading the computational power of the system.
Accordingly, the disclosed semi-private blockchain virtual currency exchange systems and methods are directed to these and other considerations.

Semi-private blockchain virtual currency exchange systems


A wire electric discharge machining apparatus is provided to equip with an automatic wire threader more reliably threading a wire electrode through an start hole. The wire electric discharge machining apparatus includes an automatic wire threader including: a feed roller disposed higher than the start hole and feeding a wire electrode toward the start hole; and a vertical drive device disposed between the feed roller and the start hole, and supplying compressed air in the upward and downward directions to vertically move the wire electrode slightly. The vertical drive device includes wire guides having guide holes through which the wire electrode is passed. The wire guides are constructed so that upward movement by the compressed air is possible.

In general, a wire electric discharge machining apparatus is equipped with an automatic wire threader which is capable of automatically threading a wire electrode through a start hole. A wire electrode of 0.1 mm to 0.3 mm in diameter is typically used. The start hole is formed in the work in advance to wire electric discharge machining. If the wire electrode is broken during the machining process, the automatic wire threader threads the wire electrode through a machined kerf in order to commence machining again. A guide pipe for guiding the wire electrode straight to the start hole or the machined kerf is provided to many of automatic wire threaders. The start hole and the machined kerf are hereinafter collectively referred to as the start hole.
The gap (hereinafter referred to as a "clearance") between the wire electrode and the start hole is small. Therefore, failure may occur if the front end of the wire electrode does not reach the start hole or is caught by the inner wall of the start hole. The feeding of the wire electrode is halted slightly after such failure is detected. At the time, the wire electrode is already loosened. The wire is tightened after the wire electrode is winded. Then, the wire electrode is again sent towards to the start hole. The failure in an automatic wire threading lengthens the required operation time.
The patent document 1 disclosed a method for eliminating the loosening of a wire electrode to avoid a repetitive failure in an automatic wire threading operation. The patent document 2 disclosed a method for guiding a wire electrode to the start hole by applying horizontal micro-vibration with compressed air. The patent document 3 disclosed a method for searching a start hole automatically and positioning the front end of the wire electrode to the entrance of a start hole.
The patent document 4 disclosed a device that eliminates a stuck wire electrode by moving the wire electrode up and down slightly. According to the invention, the operation of the device is similar to an action that a person pinches a thread and tries to thread its front end though a small hole again and again. The wire electrode is threaded through the start hole without being winded, and the time required for automatic wire threading is shortened. It has been proven that the probability of the wire electrode threading through the start hole is high even when the upper wire guide is away from the start hole.

Wire electric discharge machining apparatus


A collapsible crate includes an improved hinge for connecting side walls to the base. The improved hinge includes a hinge member and a hinge receiver. The hinge receiver includes a pair of deformable tangs each having an opening. The hinge receiver includes a hinge pin having a pair of axial ends, each extending into the opening of the tang. Each axial end of the pin includes a tapered portion, which facilitates insertion of the hinge pin into the hinge receiver.

The present invention relates generally to collapsible crates, and more particularly, to a collapsible crate with an improved hinge.
Molded plastic collapsible crates are known. Four side walls are each connected via a hinge to a base. The side walls are selectively movable about the hinge between a use position generally perpendicular to the base and a collapsed position on the base. Adjacent walls are connected at the corners using any of a variety of methods to selectively lock the crate in the use position. The side walls are moved to the collapsed position to save space when not in use.


A cryptography method involving a keyholder having a number m≧1 of private keys Q1, Q2, . . . , Qm and respective public keys G1, G2, . . . , Gm, each pair of keys (Qi, Gi) (where i=1, . . . , m) satisfying either the relationship G1=Qiv mod n or the relationship Gi×Qiv=1 mod n, where n is a public integer equal to the product of f (where f>1) private prime factors p1, . . . , pf, at least two of which are separate, and the exponent v is a public integer equal to a power of 2. Disclosed is what mathematical structure may be imparted to the public keys for it to be impossible to calculate said private keys from said public parameters in a reasonable time unless said prime factors are known. Devices adapted to implement the method are also disclosed.

Asymmetrical key cryptography systems use pairs of keys, each pair comprises a public key and a private key, and each key may include a number of parameters. Each public key is linked to the identity of its holder by a certification authority. Asymmetrical key cryptography systems include entities known as controllers that store a number of public keys in conjunction with the certified identities of their holders.
The problem of factorizing integers has been the subject of intense research since the invention of the RSA asymmetrical key cryptographic method (see the article by M. Gardner, "A new kind of cipher that would take millions of years to break", Scientific American, August 1977). The name RSA of the algorithm is derived from the initials of its inventors R. Rivest, A. Shamir, and L. Adleman. Despite considerable advances, more a result of growth in computing power than of progress in factorizing algorithms, there is still no known method of factorizing a large integer in a reasonable time. Users are therefore justified in placing their trust in the RSA method.
Each use of the RSA method is associated with an integer n known as the modulus and which is the product of two separate large prime factors p1 and p2. Given present-day computing capacities, it is recommended that moduluses of at least 1024 bits (of the order of 10308) are used. An RSA public key includes the modulus n and an exponent e that is prime with (p1−1) and with (p2−1). The corresponding RSA private key includes an exponent d such that (the symbol "mod" signifies "modulo"):e×d=1 mod[(p1−1)(p2−1)]
The security of this method relies on the fact that it is impossible to calculate d from n and e within a reasonable time if the factors p1 and p2 are not known. As explained above, it is not possible to calculate these factors (which are naturally kept secret) in a reasonable time.
The cryptographic procedure for entity authentication uses a controller and a keyholder, referred to below as the claimant, who wishes to be authenticated by the controller in order to receive an authorization, for example the authorization to access electronic data processing resources. The claimant declares an identity to the controller, and must prove to the controller that the claimant holds the private key corresponding to the public key linked to that identity.
It is possible to effect this authentication without the claimant disclosing to the controller any information at all concerning the claimant's private key: this technique is known as zero-knowledge proof authentication and is described in general terms by S. Goldwasser, S. Micali, and C. Rackoff in their paper "The Knowledge Complexity of Interactive Proof Systems" delivered at the 17th ACM Symposium on the Theory of Computing (Proceedings, 291 to 304, 1985).
In the paper "Zero-knowledge Proofs of Identity" (Journal of Cryptology, vol. 1, pages 77 to 94, 1988), U. Feige, A. Fiat, and A. Shamir propose a zero-knowledge proof cryptographic method in which the claimant holds a private key Q and publishes an RSA modulus n and a public key G=Q2 mod n (it is impossible to calculate Q from G, i.e. to calculate a square root modulo n, in a reasonable time unless the prime factors of n are known).
When the above method is applied to authenticating entities, the Fiat-Shamir procedure comprises the following interactive steps:
1. Witness step: the claimant chooses at random an integer r, calculates the "witness" R=r2 mod n and sends the witness to the controller;
2. Challenge step: the controller chooses at random an integer d called a "challenge" which can take the value 0 or the value 1 and sends the challenge to the claimant;
3. Response step: the claimant calculates the "response" D=r×Qd mod n and sends the response to the controller; and
4. Verification step: the controller calculates
      (                  D        2                    G        d              )      mod              nand verifies that the result is equal to the witness R.
For increased security, it is recommended that this procedure should be repeated "sequentially" as many times as possible before considering that authentication has been effected (varying r and d each time).
This is a zero-knowledge proof procedure because an observer cannot calculate the private key Q of the claimant from the data exchanged.
In a Feige-Fiat-Shamir or parallel variant, the claimant holds a number m>1 of private keys Q1, Q2, . . . , Qm and publishes, in addition to an RSA modulus n, respective public keys G1, G2, . . . , Gm, where Gi=Qi2 mod n for i=1, . . . , m. The following steps are then executed:
1. Witness step: the claimant chooses at random an integer r, calculates the witness R=r2 mod n and sends the witness to the controller;
2. Challenge step: the controller chooses at random m challenges d1, d2, . . . , dm where di is equal to 0 or 1 and for i=1, . . . , m and sends the challenges to claimant;
3. Response step: the claimant calculates the response D=r×Q1d1×Q2d2× . . . ×Qmdm mod n and sends the response to the controller; and
4. Verification step: the controller calculates
      (                  D        2                              G          1                      d            1                          ×                  G          2                      d            2                          ×        …        ×                  G          m                      d            m                                )      mod              nand verifies that the result is equal to the witness R.
This parallel variant accelerates the Fiat-Shamir authentication procedure compared to the sequential (i.e. series) variant referred to above.
Note further that the calculations required to implement either of these variants can be reduced if the claimant uses the Chinese remainder theorem well known to experts in number theory. The claimant may proceed in the following manner.
Consider first the calculation of the witness R. For a modulus n=p1×p2, where p1<p2, let a number C (known as a Chinese remainder) be the positive number less than p1 such that p1 is a factor of (p2×C−1). The claimant chooses at random two integers r1 and r2 such that 0<r1<p1 and 0<r2<p2 and calculates the two witness components R1=r12 mod p1 and R2=r22 mod p2. The value of the witness is deduced therefrom as follows, where z=C×(R1−R2):R=z×p2+R2
To calculate the response D, the claimant may proceed as follows. Private key components Qi,1=Qi mod p1 and Qi,2=Qi mod p2 are defined for i=1, . . . , m. The claimant first calculates the two response components:D1=r1×Q1,1d1×Q2,1d2× . . . ×Qm,1dm mod p1, andD2=r2×Q1,2d1×Q2,2d2× . . . ×Qm,2dm mod p2.The claimant then obtains the value of the response as follows, where z=C×(D1−D2):D=z×p2+D2
The advantage of this Chinese remainder calculation method is that the claimant calculates modulo p1 and modulo p2 instead of modulo n under conditions whereby p1 and p2 are generally much smaller than n.
The Fiat-Shamir entity authentication procedure may be transposed easily to verification by a controller that a message M that it has received was sent by a certain keyholder, here also called the claimant. This message authentication procedure comprises the following interactive steps:
1. Witness step: the claimant chooses at random an integer r and calculates first the witness R=r2 mod n and then the token T=h(M, R), where h is a hashing function (for example one of the functions defined in the ISO/IEC Standard 10118-3), and finally sends the token T to the controller;
2. Challenge step: the controller chooses at random a challenge d which can taken the value 0 or 1 and sends the challenge to the claimant;
3. Response step: the claimant calculates the response D=r×Qd mod n and sends the response to the controller; and
4. Verification step: the controller calculates
  h        (          M      ,                        (                                    D              2                                      G              d                                )                        mod                                                  n              )  and verifies that the result is equal to the token T.
Finally, the Fiat-Shamir entity authentication procedure can be transposed to define a procedure for signing a message M that is sent to a controller by a keyholder called the signatory; note that a signing procedure is not interactive in itself. The signatory holds a plurality of private keys Q1, Q2, . . . , Qm, where m is large compared to 1, and publishes, in addition to an RSA modulus n, respective public keys G1, G2, . . . , Gm where Gi=Qi2 mod n and for i=1, . . . , m. This signing procedure comprises the following steps (given the same names as above by analogy):
1. Witness step: the signatory chooses at random m integers ri where i=1, . . . , m and calculates first the witnesses Ri=ri2 mod n and then the token T=h(M, R1, R2, . . . , Rm), where h is a hashing function producing a word of m bits, and finally sends the token T to the controller;
2. Challenge step: the signatory identifies the bits d1, d2, . . . , dm of the token T;
3. Response step: the signatory calculates the responses Di=ri×Qidi mod n and sends the responses to the controller; and
4. Verification step: the controller calculates
  h        (          M      ,                        (                                    D              1              2                                      G              1                              d                1                                              )                        mod                                                  n            ,                        (                                    D              2              2                                      G              2                              d                2                                              )                        mod                                                  n            ,      …                                ,                        (                                    D              m              2                                      G              m                              d                m                                              )                        mod                                                  n              )  and verifies that the result is equal to the token T.
Consider now in more detail the security of the Fiat-Shamir method. For example, in the case of the entity authentication procedure explained above, the question arises: is it possible for an impostor (i.e. an entity knowing the RSA modulus n and the public key G, but not knowing the private key Q of the entity that it is pretending to be) to fool the controller?
Note first that the challenge, although random, can take only two values: if an impostor guesses the value of the challenge thrown down by the controller during the authentication procedure correctly (and thus with a 50% chance of success), could it satisfy all the steps of the Fiat-Shamir method without being caught by the controller? The answer to this question is yes. In fact:                if the impostor guesses that the challenge will be d=0 it supplies to the controller a witness R=r2 mod n and a response D=r; and        if the impostor guesses that the challenge will be d=1 it chooses any integer l>0 and supplies to the controller a witness R=l2×G mod n and a response D=l×G mod n.
The Fiat-Shamir procedure therefore has a weakness, although its effect can be attenuated, as indicated above, if the procedure is repeated sequentially to render a correct series of anticipations of the challenge by an impostor as improbable as possible. It follows that, to make this authentication procedure sufficiently secure, its duration must be considerably increased.
International application WO-00/45550 discloses a cryptography method that is applicable to an entity authentication procedure, a message authentication procedure and a message signing procedure and does not suffer from this drawback. In that method, the claimant publishes not only an RSA modulus n and a public key G but also an integer (called the exponent) v=2k where k (called the security parameter) is an integer greater than 1. Moreover, if Q is the private key of the claimant:G=Qv mod n  (1)
The authentication procedure of application WO-00/45550 comprises the following steps:
1. Witness step: the claimant chooses at random an integer r, calculates the witness R=rv mod n and sends the witness to the controller;
2. Challenge step: the controller chooses at random an integer d called the challenge, where 0≦d≦2k−1−1, and sends the challenge to the claimant;
3. Response step: the claimant calculates the response D=r×Qd mod n and sends the response to the controller; and
4. Verification step: the controller calculates
      (                  D        v                    G        d              )      mod              nand verifies that the result is equal to the witness R.
Thus in this procedure the challenge can take 2k−1 different values (as opposed to only two values in the Fiat-Shamir method), which, for a single execution of the above succession of steps, makes correct anticipation of the challenge by an impostor increasingly improbable as the value of k increases.
This being the case, to enhance security, this procedure can of course be repeated sequentially s times and/or m pairs of keys can be used in parallel as explained above; it is then advantageous to use the Chinese remainder theorem for the calculations. In practice, because a hacker has more time to crack the code in the case of signing than in the case of authentication, it is recommended that the product [(k−1)×m×s] have a value at least equal to 40 in the case of authentication and at least equal to 80 in the case of signing.
Moreover, according to application WO-00/45550, the public key is required to satisfy the following relationship, in which g is a small integer (called the base number) greater than 1:G=g2 mod n  (2)
Combining the above equations (1) and (2) shows that it is necessary to find a pair (g, Q) satisfying the following equation for given n and v:Qv=g2 mod n  (3)
It can be shown that equation (3) can be solved in a reasonable time only by someone who knows the factors of the modulus, i.e. the keyholder. In other words, calculating a pair of keys conforming to application WO-00/45550 from the corresponding public parameters is just as complicated as factorizing the number n; the two tasks are said to be equivalent in terms of complexity and a set of keys implying this kind of equivalence satisfies the equivalence criterion.
A first advantage of this state of affairs is that there is a reference level of security (i.e. the factorization problem). A second advantage is that a holder of keys according to application WO-00/45550 does not need to have such a public key certified by a certification authority, i.e. to obtain from that authority a certificate linking that public key to the identity of its holder; it is only necessary to certify the RSA modulus n, the other parameters being published directly by the holder. In contrast, in the Fiat-Shamir method, for example, it is possible for different entities to construct their own pairs of keys from the same RSA modulus (Fiat-Shamir pairs therefore do not satisfy the equivalence criterion defined above), and consequently each particular public key must be linked by a certification authority to the identity of its holder.
It can nevertheless be shown that there exist solutions of equation (3) for only certain particular moduluses n (representing about one quarter of all RSA moduluses). This is problematic for an entity seeking to produce pairs of keys according to application WO-00/45550: if that entity already has a collection of RSA moduluses, it can generally use only some of them to construct the keys, whereas if it does not already have any RSA moduluses, it will find it more difficult to find adequate moduluses than if all (or almost all) the RSA moduluses were compatible with the method.

Zero-knowledge proof cryptography methods and devices


A foldable and self-erecting display stand has an easel mounted at the rear surface of a large planar board. The planar board and the easel are together foldable along a plurality of horizontal fold lines to a compact collapsed state. The easel has a U-shaped horizontal cross section and two mutually parallel triangular side walls. A plurality of pivotable cross braces extend in a canti-lever manner from a body board of the easel. A plurality of elastic cords are mounted between the cross braces and the side walls of the easel. The side walls of the easel are foldable to a collapsed position juxtaposed to the planar board against the elastic force of the elastic cords for folding the display stand to the collapsed state. The elastic cords are in a stretched condition when the display stand in the collapsed state, and the cross braces cooperate with the stretched elastic cords to self-erecting the display stand from the collapsed state to the erected state.

Stands made of cardboard material are commonly used for displaying merchandise. They are cost effective and convenience to use. Such stands have a large planar board supported by an easel. The board may have an attractive advertising design shown on its front surface for attracting customers' attention and may also have provision for displaying merchandise hung on hooks and/or held in trays mounted to the board. The easel has an L-shaped or T-shaped leg portion for supporting the planar board to stand in a substantially vertical position. One common drawback of such stands is that the L-shaped or T-shaped leg portion of the easel is rather small in size relative to the planar board and are not strong in construction such that it may break easily in use rendering the stands unusable.
Some stands are foldable along horizontal fold lines to a compact collapsed condition for convenient storage and transportation and may also be self-erecting from the folded condition to an erected condition for easy set up of the display. The self-erecting function is provided by a plurality of elastic bands mounted directly between parallel vertical side walls of the easel. The stand and the easel may be folded in the collapsed condition by stretching the elastic bands against their elastic force, and the stand in the collapsed folded condition may be erected by holding its top portion and raising it upwards to allow the stretched elastic bands to pull the stand and easel quickly to the erected condition. It has been very problematic to select the acceptable elastic bands that may allow the stand to be folded easily as well as subsequently self-erecting. The elastic bands must not have too strong an elastic strength so that the stand and the easel may be folded with ease yet they must have a sufficient elastic strength to return the folded stand and easel to the erected condition. Another problem is that due to the direct mounting of the elastic bands between the side walls of the easel, they would cause these side walls to deform or tear at the mounting locations resulting in the loss of the integrity or strength of the side walls to support the planar board in the erected condition.
Another further common problem with self-erecting stands and easel is that the cardboard material in the folded condition retains a folded memory such that it cannot be unfolded readily to the erected condition by the elastic force of the elastic bands.

Foldable and self-erecting display stand and easel


A calendar stepping mechanism of an eternal calendar of a clock includes a month disk with indentations and elevations corresponding to forty-eight months of a leap year period and a calendar wheel having 31 teeth with one stepping tooth and normal teeth for driving a calendar date display. A stepping lever is pivoted once a day and has a probe finger that rests on the month disk in a normal position of the stepping lever. A connecting link arranged such that, during the pivoting movement of said stepping lever from its normal position into its raised position, a stepping pawl slides along the connecting link, wherein during a first part of the pivoting movement of said stepping lever, the connecting link supports the pawl tooth at a radial distance from an axis of said calendar wheel between the tip circle of the normal teeth and the tip circle of said stepping tooth and, during the second part of the pivoting movement of the shifting lever, the connecting link supports the pawl tooth at a radial distance inward of the tip circle of the normal teeth, wherein a transition from the first part to the second part of the pivoting movement of the stepping lever occurs at the point which the pawl tooth occupies when the stepping lever is in its normal position and the probe finger is in contact with one of the elevations of the stepped month disk.

The invention pertains to a calendar stepping mechanism of an eternal calendar of a clock, the stepping mechanism having a stepping lever driven once per twenty-four hours around a pivot axis between a normal position and a raised position, a probe finger on the stepping lever, which can be moved radially from the outside against the circumferential periphery of a stepped month disk, the periphery being provided with twenty indentations of different depths and twenty elevations, which represent the forty-eight months of a leap year period, where the stepped month disk can be driven to rotate at a rate of one step per month and one revolution per four years, a rotatably supported calendar wheel having thirty-one teeth or a multiple thereof, where a stepping tooth, projecting beyond the other normal teeth, is provided for each set of thirty-one teeth, wherein the calendar wheel can be advanced by a pawl tooth of a stepping pawl, which is hinged to the stepping lever and can engage radially in the gaps between the teeth of the calendar wheel under the pivoting movement of the stepping lever, this movement depending on the contact position of the probe finger on the periphery of the stepped month disk, and wherein the clock's display of the calendar date can be driven by the calendar wheel.
Eternal calendars are mechanisms which allow a clockwork to step the calendar display forward in such a way that, on the correct day at the end of each month, the calendar display is set automatically to the first day of the new month under consideration of whether the year in question is a leap year or not. The information on the correct length of the various months is stored in a stepped month disk with indentations of different depths, which advances one step each month and completes one revolution every four years. This stepped month disk causes a stepping lever to perform a stroke corresponding to the length of the month in question, as a result of which, at the end of the month, it is possible all at once to step through the appropriate number of additional days required to display the first day of the new month. It is therefore necessary for the stepping lever both to advance the wheel one day forward every day and to advance the wheel one or more days forward at the end of the month to reach the point at which the new month begins.
In a calendar stepping mechanism of the type described above, it is known that the stepping lever has two shifting elements, one of which engages in the calendar wheel to step the date forward by one day. The calendar wheel carries a worm-like disk, which is oriented in such a way that, depending on the stroke determined by the stepped month disk, the second shifting element of the stepping lever engages in the step of the worm at the end of the month and advances the calendar wheel to the first day of the new month.
Because of the presence of two shifting elements, it is necessary to adjust their position with respect to the calendar wheel and with respect to each other with great precision to ensure the correct engagement at the correct moment. For the stepping operation at the end of the month, one shifting element must take over the stepping function from the other shifting element, which leads to jerks and changes in rotational speed and which must also be adjusted with great precision.


An image pickup device includes pixels arranged in a matrix shape, vertical signal lines to which the pixels are respectively connected via normal connection lines for each column, focus detection pixels discretely arranged among the pixels, focus connection lines that set, in a range in which a total number of the focus detection pixels included in a row group including a plurality of rows is not more than a number of the vertical signal lines, the row group and respectively connect all the focus detection pixels included in the row group to the different vertical signal lines, focus readout switches respectively provided on the focus connection lines, and a vertical scanning circuit that causes the focus readout switches to simultaneously operate by a unit of the row group.

1. Field of the Invention
The present invention relates to an image pickup device including focus detection pixels, and a focus detection apparatus including the image pickup device.
2. Description of the Related Art
In recent years, to detect a phase difference occurring depending on a deviation from a focus position, development of an image pickup device including focus detection pixels that have been pupil-divided has been put to practical use and commercialized. Such an image pickup device includes one described in Japanese Patent Application Laid-Open Publication No. 2009-60597, for example.
In an image pickup device currently put to practical use, a relatively small number of focus detection pixels are only arranged in a relatively narrow specific range within its screen, and an arrangement ratio (density) of the focus detection pixels is approximately 0.5%, for example.
On the other hand, to enhance focus detection performance, a large number of focus detection pixels are desirably arranged at a higher density (or further in a wider range).

Image pickup device and focus detection apparatus


An arbor assembly includes a shank mounted to the chuck of an electric drill, an adaptor which supports a hole saw mounted to the shank, and a sleeve for locking and unlocking the adaptor and the shank. Rotational forces from the drill are transferred to the adaptor to rotate the hole saw. The sleeve slides along the outer surface of the shank and allows a user to quickly change the hole saw. With the sleeve in the unlocked position, the adaptor easily slides out of the shank, a new adaptor is inserted into the shank, and the sleeve is then placed in the locked position prior to rotation of the drill.

This invention relates to an arbor assembly which allows a hole saw to be quickly mounted and dismounted from an electric drill. Hole saws are commonly used in connection with electric drills to create holes in work pieces. It is often necessary to create holes of varying sizes and therefore is convenient to be able to quickly mount and dismount hole saws of different sizes to and from an electric drill.


An improved apparatus for dental implant treatment includes a syringe comprising a barrel portion including a slightly bended cylinder in the area of the syringing side of the barrel and comprising a perpendicularly extended rim at its another side. Also, the improved apparatus for dental implant treatment comprises a piston member rigidly connected to the connecting rod at the syringing side and handle member extended from the connecting rod's another side. The connecting rod at the handle side portion includes the threaded portion with the outer thread appropriate to the inner thread of the controlling means of the adjustment means. The improved apparatus for dental implant treatment also includes the cover coupled with the syringing side of the barrel and a separate pipette providing suction of the patient's blood from the extracted tooth socket and injecting such blood into synthetic bone graft material located in the barrel.

Presently, the methods for installing synthetic bone graft material are commonly well known. Generally the known methods provide preservation of the alveolar ridge surrounding a presently extracted root socket by backfilling the socket with bone graft material and installing an implant in the root socket area either immediately before backfilling or after backfilling and a delay in which new bone is allowed to grow into the bone graft material. It is also known, that usually, the dental implant is installed apically into the root socket immediately following root extraction. The open area of the root socket surrounding the implant is then backfilled with bone graft material immediately after implant placement. The implant is mostly a threaded implant (but it can be a cylinder-type) which is usually placed about 3 mm–6 mm apically to said root socket, as it is well known from prior art. The bone graft material comprises synthetic bone alloplast (e.g. such as Bioplant.RTM. HTR.RTM.) and is hydrated using the patient's own blood obtained from the patient's bleeding extraction socket after penetration but prior to insertion of the bone graft material and the implant into said root socket. According to the another known variant, the presently extracted root socket is filled with bone graft material and primary or non-primary closure of the extraction site is performed. Bone-growth is promoted in the root socket by the bone graft material for 2–12 months. Then, after sufficient bone growth has been promoted, an implant is installed in the extraction site area in the normal manner.
In compliance with the National Survey on Oral Health conducted by the National Institute of Dental Research, over 40% of Americans over 65 years of age and about 4% of those 35 to 64 are totally edentulous. Moreover known, that those over 65 years old who still have some of their teeth have lost an average of 12 of their 28 teeth, and persons aged 55 to 64 have lost an average of 9 of their 28 teeth. Also, it is known, when an extracted or otherwise missing tooth is not replaced, atrophy of the jaw bone occurs over time. Consequently, individuals who have been partially or fully edentulous for an extended period of time are left with an atrophic alveolar ridge that can not securely support a full or partial denture or support the placement of a dental implant. The edentulous individual faces a continuing deterioration of aesthetics and a compromised ability to chew leaving the quality of the individual's oral life in an unfortunate state.
The deteriorating effect of tooth extraction on the alveolar ridge is commonly known, and it is also well known, that a tooth of a patient, comprised of a crown and root seated in the alveolar (or jaw) bone. The buccal and lingual portion of the alveolar bone is surrounded by a layer of tissue known as the gingiva or gum. The crown and root are supported by the alveolar ridge or jaw bone and the gingiva which, in the ideal case, is adjacent to the tooth at a level gum line over the underlying bone. When such a tooth or series of teeth become infected or otherwise dentally compromised such that the extraction of the crown and root are required, the root is removed from the alveolar bone by separating the surface of the root from the periodontal membrane. The portion of the alveolar bone shortly after extraction of the crown and root has bleeding clots, such that bleeding ceases and a root extraction socket remains in the alveolar bone in the shape of the extracted root. The buccal and lingual portions of the alveolar bone are composed of bone having a unique characteristic, i.e., being capable of absorbing the shocks caused by the stress movement of teeth during speech, eating, etc. The removal of a tooth and the resulting absence of frequent use pressure in the area causes the alveolar bone to shrink in that area where pressure is no longer applied (the extraction site) with the subsequent loss of 40%–60% (in a 2 to 4 year time) of the alveolar ridge's former height measured at the gum line (i.e., "disuse atrophy"). FIG. 3 shows 30 Approximately two years after the extraction of the tooth an extraction site has various degrees of loss of buccal and crestal alveolar bone. The jaw bone continues to atrophy at a bone loss rate of ½%–1% per year until death of the patient. At the modern time, the bone graft substitute material has been used to immediately fill a root extraction socket at an extraction site after a root extraction in order to promote bone growth and to avoid the expected bone atrophy (a.k.a. "Ridge Preservation"). Bone growth is promoted via the bone graft material's intermixing with the patient's own marrow blood which seeps through the root extraction socket. After some time to allow alveolar bone regeneration (approximately 1–1.5 years) dense lamina bone forms in the extraction socket area. The patient may then be considered for a denture prosthesis.
There are known some variations of the procedure, for example, inherited in the method for installing an implant in a root extraction socket and backfilling the socket area immediately after extraction (a.k.a. "immediate post-extraction implant installation"), and the method for backfilling a root extraction socket with bone graft material immediately after extraction and then delaying installation of an implant in the root extraction socket until bone graft material has promoted sufficient bone growth in the root extraction socket (a.k.a. "delayed post-extraction implant installation").
These variations are described in the U.S. Pat. No. 6,325,627, which discloses the method and apparatus for preserving the alveolar ridge around a newly extracted root socket and providing an immediate post-extraction installation of an implant by: a) immediately installing an implant in a root extraction socket following root extraction, and b) filling the remaining space in the socket with bone graft material to encourage new bone growth in the extraction site. Generally, according to an aspect of the invention, the method for preserving the alveolar ridge around a newly extracted root socket comprises the steps of installing a dental implant apically 3 mm–6 mm to the root extraction socket, filling the remaining open area of the root extraction socket with bone graft material by a syringe and retaining the bone graft material during initial healing of the bone and gingiva with a restraint such as sutures, or a collagen or a surgical foil dressing, and/or method for delayed post-extraction installation of an implant by filling the root extraction socket with bone graft material using the mentioned syringe immediately after root extraction and, after sufficient new bone growth has been promoted by the bone graft material in the root extraction socket, installing an implant in the new bone growth utilizing known methods and apparatus for installing an implant in a normal, non-atrophied jaw bone.
The apparatus of this prior art comprises the dental syringe and implant. The syringe is presented by the straight syringe HTR.RTM.-24, Item #H216102, or curved syringe HTR.RTM.-24, Item #H216112 available from Bioplant, Inc. (20 North Main Street, Norwalk, Conn. 06854), filled with 750 micron diameter HTR.RTM. to absorb blood from the bleeding root extraction socket. The syringe generally includes the handle coupled with the piston and the straight or curved cylinder with the attachable nozzle.
Another analogous syringe is described in U.S. patent application Ser. No. 08/831,941.
All known syringes are inconvenient considering non-adjustable travel/stroke of the piston inside the cylinder. Also, the known prior art includes the nozzle, which does not provide sufficient and convenient suction of the blood from the bleeding root extraction socket (i.e., the known syringes do not provide satisfied consistent of the final mixture of the sucked blood from the bleeding root extraction socket into the bottom jaw and synthetic bone graft material (e.g. such as HTR.RTM, etc.).
Thus, there is a great need in the art for the non-expensive and convenient improved apparatus for dental implant treatment, providing easy syringe's piston travel adjustment and better mixture of the patient's own blood from the bleeding root extraction socket with the synthetic bone graft material located into the syringe's cylinder.


A method of manufacturing an OLED device with a curved light-emitting surface comprising:

Light-emissive devices are well known and used for a wide variety of purposes, including area illumination and the representation of information in displays. Traditionally, these light-emissive devices rely on evacuated glass enclosures within which are special gases, phosphors, or filaments that emit light upon the application of a current or when stimulated with an electron. More recently, solid-state light-emissive devices have created robust, long-lived, and practical displays using, for example, light-emitting diodes, liquid crystal, and plasma technologies.
Light emissive devices are useful in a variety of forms. Traditional forms include bulbs rounded in one or two dimensions, for example incandescent and fluorescent light bulbs. Neon lighting is often linear and is used to create lines of light through three dimensions. Large-format information displays such as cinemas rely upon curved screens to maintain an immersive experience for viewers and to more readily simulate a real-world environment. Hence, conventional light-emissive and display devices are found with a variety of shapes, including flat, curved in one or two dimensions, and linear.
Conventional high-output light-emitting solid-state diodes utilize light emitting diodes, typically point sources mounted into a substrate. Because individual devices are individually mounted, these devices can be mounted onto a variety of substrates with a variety of shapes. However, because these devices utilize a collection of point light sources, they require additional optical devices such as mirrors and lenses for suitable area illumination. When applied to information display, individually mounted light emitting diodes are expensive and only suitable for low-resolution displays.
Flat-panel solid-state information display devices such as liquid crystal, OLED, and plasma display devices provide good resolution. Such devices are typically built upon flat substrates, typically glass or silicon, and encapsulated with glass cover layers to provide desired environmental protection. Such structures are typically very rigid and difficult to employ in a curved configuration. The use of flexible substrates and covers for displays, typically plastic, is also known and there is increased interest in flexible, light-emitting, solid-state displays and area illuminators. Such devices typically rely upon constructing a flexible, flat light-emissive device on a flexible substrate and with a flexible cover, and then bending the device to meet the needs of an application. Typically, problems such as cracking and moisture permeation are encountered in such flexible devices.
Referring to FIG. 2, a prior-art OLED device includes an organic light-emitting layer 14 disposed between two electrodes 12 and 16, e.g. a cathode and an anode. The organic electro-luminescent layer 14 emits light upon application of a voltage from a power source 18 across the electrodes. The OLED element typically includes a substrate 10 comprising a material such as glass or plastic and is encapsulated with a cover 20. It will be understood that the relative locations of the anode and cathode may be reversed with respect to the substrate. The organic light-emitting layer 14 may include other layers such as electron or hole injection layers as is known in the art. Typically, one of the two electrodes 12 or 16 and either the cover 20 or substrate 10 is transparent to allow emitted light to escape from the OLED device. The other electrode is usually reflective.
In general, glass is employed as the substrate for solid-state displays and many illuminators. The specific properties of glass make it a suitable substrate for carrying electro-conductive layers in electric or semiconductor devices such as flat-panel displays, electro-luminescent panels, cathode ray tubes (CRTs), photovoltaic cells, etc. In addition to a high thermal and dimensional stability, glass has many other beneficial properties compared to plastic materials, e.g. the ease of recycling, excellent hardness and scratch resistance, high transparency, good resistance to chemicals such as organic solvents or reactive agents, low permeability of moisture and gases, and a very high glass transition temperature, enabling the use of high-temperature processes for applying an electro-conductive layer. However, the main problems associated with the use of glass as a substrate in electric or semiconductor devices are its high specific weight, brittleness and limited flexibility. The latter problems require the coating of a functional layer on glass to be typically carried out in a batch process (sheet by sheet).
A common alternative to glass for flexible substrates is plastic. Plastic is typically very flexible, shock resistant, and light weight, but is also porous and many light-emitting materials, for example OLEDs are sensitive to environmental contamination that may permeate a plastic substrate. However, the application of layers on a plastic support is generally performed as a continuous process, e.g. by using a web coater or continuous printing techniques such as screen or offset printing, providing improved productivity and cost efficiency.
For some applications, plastic foils may be used as a substrate for carrying electroconductive layers in spite of the many disadvantages compared to glass. The high permeability of oxygen and water through plastic substrates degrades the electroconductive layers rapidly. Some progress has been made on producing plastic foils with barrier layers to limit permeability; however the lifetime of electric devices in which such plastic foils are used is still limited and needs to be improved. In addition, an inorganic conducting layer such as indium-tin oxide (ITO) is brittle and as a result, the electroconductivity of an ITO layer is susceptible to deterioration by simply bending a flexible plastic substrate. All these effects limit the lifetime of such flexible plastic substrate based devices considerably. Other problems associated with plastic substrates include inorganic electroconductive layers such as ITO may require an annealing step at an elevated temperature which is not compatible with most plastics.
A variety of solutions are proposed to overcome the problems and provide some of the advantages recited above. For example, U.S. Pat. No. 6,197,418 entitled "Electroconductive glass laminate" discloses a material that comprises a substrate and an organic electroconductive layer provided on said substrate, characterized in that the substrate is a laminate comprising a glass layer and a support. The glass layer is preferably a flexible glass layer having a thickness from 10 to 500 μm. The material can be used as an electrode in electric or semiconductor devices thereby providing an improved lifetime, e.g. displays, photovoltaic cells or light-emitting diodes. US20030062830 entitled "Reinforcement of glass substrates in flexible devices" describes a reinforcement technique used in the fabrication of displays, such as organic light emissive diode displays. A stiff reinforcement lid is mounted on a thin substrate to encapsulate the OLED cells. The lid serves to reinforce the thin flexible substrate and protect it from breakage. It comprises preferably of metal or other materials that have higher stiffness and ductility than the thin substrate. The fabricated display is compatible for integration into chip cards and other flexible applications.
US20020001046 A1 entitled "Apparatuses and methods for forming assemblies" describes various means to form flexible active-matrix displays along a length of flexible substrate. Another embodiment of the invention relates to forming multiple flexible displays along a continuous flexible substrate. Another embodiment of the invention relates to forming a flexible display along a flexible reflective substrate.
US20030184704 entitled "Display Device and Method of Manufacturing the Same" describes a display device comprising a first plastic substrate, a first adhesion layer formed in a first region of the first plastic substrate, the first region being a region where a pixel region is to be formed thereon, a second adhesion layer formed in a peripheral region outside of the first region of the first plastic substrate, a first thin glass layer formed on the first and second adhesion layers, a plurality of active elements formed on the first thin glass layer in one-to-one relation with a plurality of pixels, a display part formed on the first thin glass layer, the display part corresponding to the pixel region and being driven by the plurality of active elements, and an opposing substrate formed over the display part. Such laminated structures can provide a more environmentally tolerant substrate with a greater flexibility. Nonetheless, continuous flexing of such structures can lead to failure and may not provide the process compatibility necessary for OLED display processing.
In many applications, flexibility over time is not necessary so that a flexible display screen may be coupled to a substrate to provide a conformable display that is fixed in shape. Hence, the display screen is flexed only a limited number of times before being fixed in position. For example, WO2003020545 entitled "Conformable Vehicle Display" discloses a conformable vehicle display that includes a flexible display screen coupled to a substrate. The substrate is a curved transparent substrate that is adapted to be coupled to a vehicle component having a curved exterior surface. The flexible display screen is at least partially separate from the exterior surface of the vehicle component and has a luminescent display. The exterior surface of the vehicle component is visible through the flexible display screen and the substrate when the flexible display screen is not activated. The flexible display screen may be a transparent organic light emitting diode display device. However, such a design still requires that an entire display screen itself be flexible, and therefore suffers from the same environmental exposure and lifetime problems found in the OLED flexible display art.
U.S. Pat. No. 5,652,930 discloses a curved information display may be adapted as an exterior display conforming to curved surfaces of a camera casing. In such embodiment, organic electroluminescent material is applied in predetermined patterns to a flexible support, and the flexible support is applied to a rigid support, such as the camera casing or other structure conforming to the shape of the camera casing. The electroluminescent patterns are then coupled electrically to a camera control for selectively applying voltages to the patterns, causing the patterns to luminesce. The flexible display is described as comprising a transparent flexible substrate, and a first transparent conductor, an organic electroluminescent pattern layer, and a second transparent conductor, respectively, coated or otherwise deposited on the flexible substrate, along with a sealing layer 208 applied for mechanical and environmental protection. Such flexible display design still fails to teach encapsulation of a curved display in a manner that solves the environmental exposure and lifetime problems found in the OLED flexible display art.
In an alternative approach to making a curved display or illuminator, a curved, rigid substrate may be employed having the desired display shape, and the materials comprising the device are formed directly on the curved substrate. Such a manufacturing process is described in US2004/0135160. Most display manufacturing equipment, however, is designed for planar surfaces so that the deposition of materials on a curved surface is difficult and the manufacturing infrastructure for supporting such deposition is not available.
There is a need therefore for an improved process for making solid-state OLED light emissive devices having a curved display surface for area illumination or information presentation.

Method of manufacturing an OLED device with a curved light emitting surface

Abstract: a) forming a flexible substrate and providing the flexible substrate in a flat configuration;

Abstract: b) forming one or more OLEDs having a first electrode, one or more layers of organic material, at least one of which is light emitting formed over the first electrode, and a second electrode formed over the one or more layers of organic material, on the substrate;

Abstract: c) forming a rigid, curved, encapsulating cover;

Abstract: d) conforming the flexible substrate, electrodes, and one or more layers of organic material to the rigid, curved, encapsulating cover; and

Abstract: e) sealing the conformed flexible substrate, electrodes, and one or more layers of organic material to the rigid, curved, encapsulating cover.


A pressure relief valve for a tire rim in which a valve body has first and second chambers separated by a restricted passageway of reduced dimensions. The valve body has an inlet connected to the first chamber, and an outlet connected to the second chamber, and can be mounted in a suitable opening in a tire rim with the inlet exposed to pressure within the tire and the outlet exposed to the atmosphere outside the tire. A valve member is normally located in the first chamber and is seated against a seat at the entrance to the restricted passageway by air pressure within the tire acting on it via the inlet, sealing the outlet. Either the valve member or the walls of the passageway, or both, are made of deformable elastomeric material so that when the air pressure rises above a predetermined safety level, the ball is forced through the passageway into the second chamber into a position in which air can flow past the ball and out through the outlet, reducing the internal pressure in the tire.

The present invention relates generally to pressure relief valves, and is particularly concerned with a pressure relief valve for a tire rim.
Pneumatic tubeless tires are traditionally mounted on tire rims by filling the tire with air, the internal pressure in the tire forcing the tire onto the tire seat at the rim. This can be a dangerous procedure, since over-inflation of tires can occur, particularly where parts are mismatched. Such over-inflation will eventually cause the tire to explode or the wheel itself to break, potentially maiming or even killing the tire changer or other persons in the vicinity. Many injuries and deaths have occurred as a result of such accidents.