Abstract: There is provided a battery breaker comprising a case, a fixed contact which is mounted to the inner bottom surface of one end of the case and is connected to a terminal extending from the case outwards, an elastic movable piece which is mounted such that its tip end protrudes into the case through the other end of the case and allows a movable contact provided at the tip end to bring into contact with the fixed contact by the spring action, and a convex curved surface-shaped bimetal which has a warping center located in the substantial center or at a position slightly one-sided from the center, is placed between the movable piece and the inner bottom surface except for the above one end of the case so as to cover a projection provided on the above inner bottom surface without interference of an outer periphery of the bimetal with the inner side surfaces of the case, and is warped at a predetermined working temperature to push up the movable piece for separating the movable contact from the fixed contact, whe

Abstract: An improved system and method for tracking of student attendance and student movement, the monitoring of student possession and use of institutional inventory, securing authorized student access to the institution and test sessions, and monitoring student progress in learning employing a data processing telecommunications network having wireless communication capability, an electro-optical reader, a student identity card having encoded indicia thereon correlatable to the student's identity and readable by the electro-optical reader, and a processor for correlating confirmed student identity information with student activity information.

Abstract: A radio pager system includes a radio pager that can receive messages and can specify a specific output mode, including a display, a sound output, a vibration, and a light emission appropriate to a particular type of message. The radio pager can further reduce difficulties in retransmitting and/or replying to messages and save time in the transmission period. The radio pager can receive and implement a radio message that includes control information which can be utilized for generating the specific output mode of the display.

Abstract: A pager in which is written a paging ID shared among the remaining pagers of the same group, the pager including storage means for storing a character string; data comparing means for comparing the character string included in a received message with the data stored in the storage means; and operation execution means for commencing an operation on the basis of the result of the comparing operation performed by the data comparing means. The storage means is made interchangeable among pagers, or the data stored in the storage means can be rewritten. Categories of pagers in the same group may be readily established or changed through interchanging of the storage means or through rewriting of the data stored in the storage means.

Abstract: A system and method for interrogating a passive acoustic transponder, producing a transponder signal having characteristic set of signal perturbations in response to an interrogation signal, comprising a signal generator, producing an interrogation signal having a plurality of differing frequencies; a receiver, for receiving the transponder signal; a mixer, for mixing the transponder signal with a signal corresponding to the interrogation signal, to produce a mixed output; an integrator, integrating the mixed output to define an integrated phase-amplitude response of the received transponder signal; and an analyzer, receiving a plurality of integrated phase-amplitude responses corresponding to the plurality of differing frequencies, for determining the characteristic set of signal perturbations of the passive acoustic transponder.

Abstract: A method of allocating a remote control to a base station. The base station delivers a search signal. The remote control receives the search signal, compares it with a reference signal, and delivers a contact signal if they match. On receiving certain contact signals in response, the base station then delivers an identification signal, and after receiving it, the remote control sends back to the base station a code signal identifying it unambiguously.

Abstract: A communication system having at least two communication subscribers unidirectionally or bidirectionally exchanging data that are electrically connected to one another via at least one network cable which is in turn, connectible to a network termination via which energy can be supplied to the communication subscribers and via which an at least two-channel transmission of data in the form of electrical signals can occur at the same time from a first to a second communication subscriber.

Abstract: A method for allocating identifiers, that are contained in signals issued by transmitters arranged in a tire pressure monitoring system, to the positions of the wheels by transmitting the signals to a receiving and analysis circuit, which analyses the information, contained in the signal, wherein for differentiating between wheels on the right side of the vehicle and wheels on the left side of the vehicle, the sign of a translation acceleration b is determined for each running wheel, the sign of the variation of the centrifugal acceleration z occurring during the translation acceleration b is additionally determined and multiplied by the sign of the translation acceleration b determined for the respective wheel, and the differentiation between wheels on the right side of the vehicle and wheels on the left side of the vehicle is effected by comparing the products of the two signs determined for the wheels.

Abstract: A network management apparatus and method for determining an optimum threshold value for a monitored characteristic of a network is described. The optimum threshold value is determined by counting a number of previously received events generated from values for a monitored characteristic which were above or below an existing threshold value for the monitored characteristic, and determining the optimum threshold value in dependence on the counted number. An optimum threshold value is provided, which is tailored to suit the network concerned.

Abstract: A surveillance system utilizing a plurality of communication devices that are operative with portable telephones to permit an easily reconfigurable remote surveillance area. The portable telephones can have audio and imaging transmitting functions and at least one has an audio and imaging receiving function. An image sensor can sense images within a predetermined area and is operatively connected to a portable telephone for providing an output signal upon detection of a predetermined amount of change in the image area. An auto-dialing section is connected to a first telephone for calling a second remote telephone automatically based on the output signal. Infrared detecting sensors can also image within the surveillance area and be utilized to activate the auto-dialing function. The portable telephones can further include an image sensor for providing an image of the surveillance area.

Abstract: A vision system that is capable of computing the crowd densities, shopper movement speed and direction, and queue lengths at different locations in a shopping center makes recommendations for least-cost path through a set of destinations. Well-known person-counting techniques may be employed. One type of output display is a map display with an overlay an optimal route through a shopping venue.

Abstract: Each embodiment (10, 110 and 210) includes a magnetic element (12, 112 and 212) producing a magnetic field. In the first embodiment (10) of FIG. 1, the magnetic element (12) comprises a magnetic bit strip disposed extending in a circular arc on a fixed or stationary plate (14). In the second embodiment (110) of FIG. 2, the magnetic element (112) comprises a magnetic bit strip supported on a movable bar or rod (114). In the third embodiment (210) of FIG. 3, the magnetic element (212) comprises a magnetic bit strip disposed in a rectilinear path on a stationary plate (214). An electrical resistor (16, 116 and 216) is included for changing in electrical resistance in response to changes in the magnetic field produced by the magnetic element (12, 112 and 212). The resistor (16, 116 and 216) comprises a giant magnetoresistive sensor.

Abstract: Failures associate with bad hand pieces and blade failures in an ultrasonic surgical system are distinguished by monitoring the rate of change of the resonance frequency and the rate of change of the resonance impedance of the hand piece/blade as the drive frequency is changed. As the system reaches resonance, the control system locks onto the resonance frequency. When a loss of lock occurs with no recovery, the rate of change of the frequency and rate of change of the impedance are compared to obtain the fastest rate of change which is stored in non-volatile memory of the ultrasonic generator. If the rates of change are higher than normal rates of change due to temperature changes with the longest blades, a “Bad Blade” message is displayed on an LCD.

Abstract: A system is provided to allow a computer to control one or more devices using the remote control codes that are normally used by remote control units associated with these devices. The system has one or more remote control units for transmitting commands, one or more devices to be controlled, and a computer. The computer is coupled to an input device, and has a memory, a receiver which receives codes from the remote control units, and a knowledge base for storing the codes received from the remote control units and command identifiers provided from the input device. The knowledge base associates each command identifier with a particular code. The computer also includes a transmitter which transmits codes to the device to be controlled based on selected command identifiers. During configuration, the computer executes a program that prompts the user to enter a command identifier and code to be associated with that command identifier.

Abstract: A system and method of communicating among devices via a piping structure using at least one induction choke about the piping structure to route a time-varying current carrying communication signals between the devices. A communications system comprises a piping structure, a first communication device, a second communication device, and an induction choke. The piping structure comprises a first location, a second location, and an electrically conductive portion extending between the first and second locations. The first and second locations are distally spaced along the piping structure. The first and second communication devices are each electrically connected to the electrically conductive portion of the piping structure along the first location and second location, respectively, and each is adapted to send and receive communication signals via time-varying current.

Abstract: An electronic meter, such as an electronic energy meter, includes a sensing circuit for sensing one or more values of a waveform, a memory having a memory bus, a digital signal processor coupled to the memory for calculating at least one parameter value of the waveform in response to the sensed values, and a microcontroller coupled to the memory for performing control functions of the electronic meter. The digital signal processor generates a bus request when access to the memory is required. The microcontroller grants access to the memory in response to the bus request. The sensing circuit may sense and digitize current and voltage values of a polyphase power line.

Abstract: A system and method for controlling traffic and traffic lights and selectively distributing warning messages to motorists includes a controller to determine appropriate action based on traffic congestion parameters. Fuzzy logic is used to determine optimum traffic light phase split based on the traffic information from the traffic information units. Global Positioning System technology is used by the system and method in order to track moving vehicles and signs and be able to communicate with them.

Abstract: A warning indication system and method of using the same in conjunction with a cargo door of an aircraft. The cargo door is positionable in an opened position; a closed position; a closed and latched position; and a closed, latched, and locked position. The method includes outputting first and second closed signals when the cargo door is in the closed position; outputting first and second latched signals when the cargo door is in the closed and latched position; and outputting first and second locked signals when the cargo door is in the closed, latched, and locked position. All of the signals are then analyzed to positively determine the position of the cargo door, while minimizing the probability of false indications. Various warnings are generated in response to the combination of signals received. The apparatus employs a dual logic system and redundant sensors to provide differing warnings dependent on the phase of flight.

Abstract: An emergency warning system including a sensor for detecting an environmental condition. A first transmitter is connected to the sensor for broadcasting a communication signal carrying information describing the environmental condition. A first receiver receives the communication signal from the first transmitter. A second transmitter is connected to the first receiver for broadcasting an alert signal carrying information describing the environmental condition. A second receiver receives the alert signal from the second transmitter and has an indicator for exhibiting the information indicative of the environmental condition.

Abstract: A keypad arrangement for an electronic device comprises a keypad comprising activatable keys. It comprises also input signal means (801, 802, 901, 1001, 1601) for bringing an electric input signal to the keypad, and signal conversion means (703, 705, 807, 808, 809, 810, 811, 812, 813, 818, 1208, 1206) for responding to a key activation by selectively converting the input signal into an electric output signal the value of which depends on the activated key. Additionally there are output signal detection means (902, 903, 904, 1002, 1602) for detecting the value of the electric output signal. The arrangement comprises a first electromagnetic coupling (706, 708, 709, 710, 803) between the input signal means and the signal conversion means, and a second electromagnetic coupling (707, 711, 804) between the signal conversion means and the output signal detection means.

Abstract: The present invention provides an entropy coding scheme using an adaptable prefix code. The prefix code is a binary representation of the algorithm used to compress and decompress the data. There are prefix zeros that represent the number of significant binary digits that follow the first one. According to one embodiment, this scheme works on both positive and negative integers and encodes lower order integers with a smaller length of codeword. In another embodiment, the zero integer is encoded as a special case with the shortest codeword. In yet another embodiment, the present scheme is preferred by data sets that are clustered about zero, such as image data sets that have been transformed via a wavelet transform or a discrete cosine transform.

Abstract: An encoding scheme simplifies the TMDS encoding algorithm described in the DVI 1.0 specification while retaining compatibility with most existing DVI receivers. The generation of the Transition Control bit has been removed; and although the INV bit has a similar function to the DC bit in the DVI 1.0 standard, the algorithm for deriving it is very different. No attempt is made to maintain a DC balance on the cable. Instead, the INV bit is set to a ‘1’ for the purpose of removing ‘rogue’ character sequences; otherwise it is always set to a ‘0’.

Abstract: A system and method for lossless data compression. A mathematical transform equivalent to the content value of the data, and taking fewer bits to represent, is found.

Abstract: A method and system for correcting quantization loss of a signal during analog to digital to analog signal conversion, wherein the quantization loss is a function of (sin x)/x, is disclosed. The system and method of the present invention includes utilizing a continuous function polynomial to represent a (sin x)/x function, and applying an inverse function of the continuous function polynomial to the signal to provide a correction for the quantization loss.

Abstract: Unwanted voltage drops associated with the bit switches of a DAC are compensated with an output amplifier circuit for the DAC that includes a feedback circuit with a switch compensation resistance element that is connected in a combined series/parallel circuit with a feedback resistance circuit, so as to reduce both the size and associated capacitance of the resistance element.

Abstract: An analog multiplier 11 raises a base reference voltage “Vref0” to the nth power so that a reference voltage “Vref1” is produced. Analog multipliers 12 and 13 sequentially raise the reference voltage “Vref1” to the nth power so that reference voltages “Vref2” and “Vref3” are produced. Switch groups 38-41 control the reference voltages “Vref0” to “Vref3”, which are then sent to an analog multiplier 14 together with an input voltage “Vin”. A comparator 14 sequentially compares a multiplication result “Vx” of the multiplier 14 with a voltage “Vout” outputted from a sensor circuit 2, so that a digital output value “Dout” is produced. The analog multiplier 14 is set as appropriate.

Abstract: A way of converting digital signals to analog signals is provided for wireless communications. An apparatus is provided that comprises a resistive-ladder array to convert a first portion of a digital input signal to a first analog output signal. The apparatus further includes a current-mode array to convert a second portion of the digital input signal to a second analog output signal.

Abstract: An improved analog to digital converter is disclosed incorporating a flash converter and a charge-sharing pipelined chain converter. The invention incorporates three important circuits including a novel voltage reference steering circuit, a novel high performance low power comparator circuit and a novel digital calibration for compensation circuit. The low power is accomplished by turning on compare circuits only when comparing (controlled by timing circuits that are common to all comparators) and by a low power RAM that properly aligns the converted data. The converter operates in a pipelined manor and requires multiple sample and hold circuits for the compare circuits. The improved analog to digital converter incorporates test and calibration to compensate for variations experience during operation and manufacture of the improved analog to digital converter.

Abstract: The present invention is to provide an average bubble correction circuit which will expand the range of bubble error correction and will detect the proper position of the 1/0 state-conversion points of the thermometer codes to low down the error rate that caused by the ROM decoding. The average bubble correction circuit is used in the analog to digital converter and will convert the thermometer code obtained from the comparator of the analog to digital converter into the 1/0 state-conversion point.

Abstract: A system is provided, for use in “cross-eye” ECM systems, and in other application, by means of which two radio-frequency signals having a specific temporal relationship can be amplified in the same amplifier, and without significantly affecting their temporal relationship. One signal is stored in a first delay line and the second is stored in a second delay line of larger capacity. The first signal upon emerging from the first delay line is sent to the second delay line behind the second signal. Upon emerging from the second delay line, after the first signal has completely entered the second delay line, the second signal is amplified in an amplification device and sent to the first delay line. It thus emerges from the first delay line at the same time as the first signal emerges from the amplifier, or the two emerge from the first delay line and the amplifier, in their original temporal relationship.

Abstract: A radar-plow drillstring steering system comprises a steering plow and a measurements-while-drilling instrument for mounting just behind the drill bit and downhole motor of a drill rod. The instrument includes a radar system connected to upward-looking and downward-looking horn antennas and a dielectric-constant sensor. The steering plow includes four pressure pads radially distributed around the outside surface and their associated servo motors. A coordinated control of the pressure pads allows the steering plow to push the drillstring and drill bit up-down-left-right. The antennas and sensor are embedded in respective ones of the pressure pads and are used to electronically and non-invasively probe a coal seam to locate its upper and lower boundary layers. The dielectric-constant sensor provides corrective data for the up and down distance measurements. Such measurements and data are radio communicated to the surface for tomographic processing and user display.

Abstract: The dual synthetic aperture array system processes returns from the receiving arrays. The two identical receiving arrays employing displaced phase center antenna techniques subtract the corresponding spectrally processed data to cancel clutter. It is further processed that a moving target is detected and its velocity, angular position and range is measured, in or out of the presence of clutter. There are many techniques presented in the disclosure. These techniques are basically independent but are related based on common set of fundamental set of mathematical equations, understanding of radar principles and the implementations involved. These many techniques may be employed singly and/or in combination depending on the application and accuracy required.

Abstract: A self-modulating, remote, moving target detector for intrusion alarms, vehicle detection, and remote speed and distance measurement that includes a remote continuous wave radar transceiver that is used to detect moving targets. The same frequency used for the radar transmission is modulated in a continuous manner in order to transmit radar data concerning a moving target to a remote location away from the radar transceiver. The transceiver oscillator is self-modulated by the reflected signal received from a moving target in the transceiver and retransmitted such that the primary radar signal becomes the information carrier concerning the moving target, which is received remotely, in order to activate an alarm or a display system showing the moving target. The system could be utilized with any frequency from audio to light, with RF and microwave of primary interest.

Abstract: Method and apparatuses for receiving and tracking satellite signals in a highly sensitive and accurate receiver. In one aspect of the invention an exemplary method includes generating a set of at least three indicators based on processing a portion of a satellite positioning system signal received by a receiver and computing a measurement of a parameter from an interpolation of the set of indicators. Each of the indicators corresponds to a different predetermined hypothesized value of the parameter and is indicative of a probability, or likelihood, that the parameter of the signal is equal to that corresponding value.

Abstract: Methods and systems for measuring coordinates of a target, particularly under strong multipath conditions, are described. A satellite navigation system antenna and a tilt sensor are mounted on a range pole, with the sensor at the pole's bottom tip. Signals from the antenna and tilt sensor are provided to a receiver, which computes the antenna's coordinates from the antenna signals, and the pole tips position from the computed coordinates and the tilt data. The operator places the pole tip on the target and swings the pole by hand over an angle sector of 15 degrees while keeping the tip on the target. Height of the target can be computed with a single measurement set, and X-Y coordinates with just three measurement sets. The use of additional measurements reduces errors in the target's coordinates since multipath errors are uncorrelated during movement of the antenna. Vertical alignment of the pole is unnecessary.

Abstract: An antenna element includes a substrate formed of a dielectric material having a specific inductive capacity exhibiting frequency distributing properties, a grounding conductor formed on one surface of the substrate, a plurality of radiating conductors formed on the other surface of the substrate, and a plurality of feeder lines provided for passing through the substrate for connecting the grounding conductor to the radiating conductors. This antenna element is able to achieve equivalent gain for plural frequencies.

Abstract: The invention relates to a diversity reception system for motor vehicles for digitally modulated terrestrial and/or satellite radio signals in the frequency range above 1 GHz. The system includes an antenna arrangement of which the reception signal is supplied to a radio receiver. The antenna arrangement is designed as an antenna system having several individual antennas and several antenna components, and contains a controllable logic switching device. The individual antennas and the several antenna components are positioned on the vehicle so that for discrete switching positions of the controllable logic switch, reception signals that are different in terms of diversity are available at the antenna connection point. A reception level testing device is provided for the comparative determination of the reception level contained in the data flow in the HF-channel with an HF channel bandwidth B.

Abstract: The surveillance system provides a means to augment Automatic, Dependent Surveillance-Broadcast (ADS-B) with “look alike ADS-B” or “pseudo ADS-B” surveillance transmissions for aircraft which may not be ADS-B equipped. The system uses ground based surveillance to determine the position of aircraft not equipped with ADS-B, then broadcasts the identification/positional information over the ADS-B data link. ADS-B equipped aircraft broadcast their own position over the ADS-B data link. The system enables aircraft equipped with ADS-B and Cockpit Display of Traffic Information (CDTI) to obtain surveillance information on all aircraft whether or not the proximate aircraft are equipped with ADS-B.

Abstract: Method and apparatus for providing a configurable circuit are disclosed. In addition, method and apparatus for providing a phased array antenna having an integrated configurable circuit are provided. According to the present invention, at least a first component of a configurable circuit is formed on a first substrate. At least a second component of a configurable circuit is formed on at least a portion of a moveable cantilever formed from a second substrate. The first and second substrates are registered with one another to form a completed configurable circuit. According to the present invention, a configurable circuit may comprise a variable capacitor or a switch. In addition, a configurable circuit may be used in connection with phase shifting a radio frequency signal provided to an element of a phased array antenna.

Abstract: An antenna is provided which can reconcile a low antenna resonance frequency and broadband frequency characteristics, while attaining stable impedance characteristics and enhanced design flexibility. A conductive plate is coupled to a conductive base plate via a first metal lead. A voltage is applied to the conductive plate from a supply point via a second metal lead. A conductive wall is electrically coupled to the conductive plate at one end thereof. An electromagnetic field coupling adjustment plate is electrically coupled to the other end of the conductive wall. The electromagnetic field coupling adjustment plate is disposed so as to leave a predetermined interspace between itself and the conductive base plate, thereby creating a capacitor in conjunction with the conductive base plate.

Abstract: A portable telephone includes a metal substrate, a shield box, a monopole antenna and a feed unit. The surface of the metal substrate includes a conductive metal layer. The shield box covers a radio transmitter-receiver unit provided on the metal substrate to electromagnetically shield the radio transmitter-receiver unit, and has conductivity. The monopole antenna extends in a predetermined direction, and has an electrical length of (&lgr;/2)×N (N is an integer). The feed unit is provided at the metal substrate so as to be apart from the shield box in the extending direction of the monopole antenna. The feed unit includes a matching circuit.

Abstract: An antenna for receiving satellite signals and terrestrial signals comprises a monopole having a first end, which is connected to a feeding point, and a second end, and an unfed dipole which is arranged in spaced relationship with the second end of the monopole and in axial alignment with said monopole. By means of this arrangement a maximum antenna gain lying at an elevation angle of approx. 45° is achieved. An antenna modification device comprises a dipole and a connection element by means of which the dipole can be connected to the end of an existing monopole antenna in such a way that the dipole is unfed and arranged in spaced relationship with the second end of the monopole as well as in axial alignment with the monopole.

Abstract: A reflector antenna for use on a geosynchronous spacecraft or satellite for providing Earth coverage has a gain or directivity which is two or three dB greater at the edges than at the beam center, to provide coverage with more or less uniform field strength at the Earth's surface. The reflectors may be based on diverging prime focus or offset-feed parabolas, in which case the reflective surfaces of shaped reflectors have, in at least one plane, a central convex region and an “edge” convex region, separated by a concave region. The reflectors may be based on converging prime focus or offset-feed parabolas, in which case the reflective surfaces of the shaped reflectors have, in at least one plane, a concave central region.

Abstract: A null direction control method allows optimum antenna weights forming designated null beam directions without calculating an inverse matrix. In an N-element array antenna, a designated null beam antenna pattern is obtained by processing a 2-element antenna weight vector forming a null in a sequentially selected one of M designated null directions and a (N−M)-element antenna weight vector forming a beam in a designated beam direction to produce an antenna weight vector for the N-element array antenna. The final antenna weight vector is calculated by incrementing the number of elements of a work antenna weight vector each time a null is formed in a sequentially selected one of the M designated null directions.

Abstract: An antenna system adapted to be mounted on an exterior surface of a mobile platform and having a reduced overall height to reduce aerodynamic drag caused by the antenna system. The antenna system includes a movable platform disposed concentrically within an annular stationary platform. The movable platform includes a slip ring assembly formed on its lower surface which is in physical contact with a brush assembly supported from a lower surface of the stationary platform. By locating the slip ring assembly and the brush assembly adjacent the lower surface of the movable platform, the overall height of the antenna is reduced. Reliability is also improved since contaminants are less likely to accumulate on the slip ring assembly due to its presence on the lower surface of the movable platform.

Abstract: The present invention provides an HMD system for reducing a harmful influence on eyes and for providing enhanced presence. A screen display portion is moved by means of a driving mechanism based on a control signal output from a video playback device. Furthermore, the screen display portion 2 is moved according to how a wearer has reacted. Therefore, an intention of a producer of video software can be reflected in the HMD. Therefore, even in a case of a two-dimensional video without bidirectional property and with inflexible video unfolding, enhanced presence can be reliably provided to the wearer. Because a relationship between positions of eyeballs and the screen display portion is not fixed, the harmful influence on eyesight can be reduced. Furthermore, because the system has a driving mechanism 3, a gyro sensor portion 4, and a control portion 5 for the screen display portion 2, the screen display portion can be moved arbitrarily in any direction and the above control can be carried out accurately.

Abstract: The present invention relates to an AC-type plasma display apparatus, an object of the invention is to provide the AC-type plasma display apparatus improved a quality of a picture of a display image by realizing a multi-sub-field arrangement and a high gray scale arrangement, after by being realized an address discharge at high speed. As illustrated in FIG. 1, an address discharge is constituted so as to be driven at high speed by applying preset pulses 105 of a narrow width prior to time of application of a scanning pulse 106 exceeding a value of a discharge breakdown voltage, and by carrying out growth (growing process of Townsent) of a space charge by the preset pulses 105.

Abstract: A driving method during the reset period of a plasma display, which includes a display panel with a plurality of display units for sealing the inert gas. Each display unit forms an equivalent capacitor and includes a first electrode, a second electrode, and a driving circuit that exerts voltage pulses to the display units to form wall charges on the surfaces of the two electrodes or to reduce the wall charges that have been formed. The method involves applying a first soft erase pulse on the first electrodes of the plurality of display units to reduce the wall charges of the plurality of the display units followed by applying a soft priming pulse on the second electrodes of the plurality of display units to re-generate the wall charges of the plurality of display units.

Abstract: A display device includes (a) a plurality of pixels arranged in a matrix, each of the pixels including a light-emitting device, a switch and a transistor, (b) a scanning line extending in a first direction, (c) a data line extending in a second direction perpendicular to the first direction, (d) a first bias voltage line extending in the second direction, (e) a bias voltage generating circuit which applies a bias voltage to the bias voltage line, (f) a second bias voltage line which surrounds the pixels and is a closed line, and (g) a third bias voltage line which electrically connects the bias voltage generating circuit to the second bias voltage line. The first bias voltage line is electrically connected at opposite ends thereof to the second bias voltage line. The switch is turned on when the scanning line is activated, to thereby allow image signals to be transmitted to the gate of the transistor therethrough from the data line.

Abstract: A liquid crystal driving integrated circuit capable of adjusting display contrast and requiring no externally attached components. Transmission gates TG0-TG10 are provided at respective connection points of twelve resistor elements connected in series between a power supply and the ground. One of the voltages V0-V10 derived from the transmission gates TG0-TG10 in accordance with control signals CA0-CA10 is applied to an operational amplifier 8, and used as a reference voltage VLCD0. The control signals CA0-CA10 are obtained by decoding control data D0-D3 supplied from an external source by a decoder 19. Therefore, the reference voltage VLCD0 can be set in a plurality of stages simply by changing control data D0-D3 to a user specified value. As the twelve resistor elements connected in series are formed on the same semiconductor substrate, display contrast can be adjusted without requiring any external components attached to a liquid crystal driving integrated circuit 1.