Abstract: A system and method for transmitting data from a utility meter, such as a power meter, is disclosed. A microprocessor housed inside the power meter obtains readings of various power indicia, stores the readings in memory, and determines an efficient means of formatting the data for transmission to a remote host computer for further processing and use. The data is selectively compressed to minimize the amount and size of data that needs to be transmitted. The microprocessor is mounted on a circuit board assembly within the power meter housing and interfaces between the meter board of the power meter and a transmitter. The transmitter communicates the formatted and potentially compressed data from the power meter to the remote host computer wirelessly or via hard-wired communication lines. The various power indicia include power usage or power quality information.

Abstract: A transfer switch configured particularly for use with traffic signal controllers, to enable a traffic signal controller to be powered by a portable electrical generator, when utility line power is unavailable. A housing, configured to be mounted either on the surface of a traffic signal controller cabinet, or recessed into an opening of the cabinet, so as to be flush to the surface thereof, is provided. The housing is configured to be substantially weatherproof without requiring the use of gaskets.

Abstract: A navigation device stores road data that includes positions of toll roads where payback of a part of a toll is provided based on a used distance of each of the toll roads. The navigation device computes a traveled distance of the relevant toll road to thereby compute the used distance of the toll road based on the computed traveled distance. Thus, the used distance of a toll road can be accurately computed, even when a vehicle travels a loop line within the toll road by multiple circles. Information that relates to the payback and includes the used distance of the toll road is then transmitted to a center to thereby receive a partial payback of the toll.

Abstract: A device to facilitate a user interface of a computer system utilizing breath includes a body, a user side inlet defined by the body to receive a fluid flow generated by a user, an exhaust opening defined by the body, a conduit positioned between the user side inlet and the one exhaust opening, at least one segment positioned inside the body and one or more contactors positioned to be intermittently in contact with the at least one segment. The contact may occur responsive to the fluid flow generated by the user. The device may include a sensor to react to a movement of the at least one segment.

Abstract: A decoding device includes a variable-length decoding circuit, a first buffer, a second buffer and a DC/AC prediction circuit is disclosed. The variable length decoding circuit decodes a first block and a second block from a compressed media stream. The first and second buffers are electrically coupled with the variable-length decoding circuit to store the first block and the second blocks, respectively. The DC/AC prediction circuit is electrically coupled with the first buffer and the second buffer. The DC/AC prediction circuit may read the first block from the first buffer when the second buffer is storing the second block.

Abstract: A decoder circuit includes a first delay means for delaying unit data read out from a dictionary, a selecting means for selecting data and a second delay means for delaying data selected by the selecting means, wherein delayed data from the second selecting means is written again in the dictionary, the selecting means is supplied with delayed data from the first delay means and delayed data from the second delay means and the selecting means selects delayed data from the second delay means if a read address and a write address of the dictionary fall within a range of a predetermined distance corresponding to delay amounts of the first and second delay means and the selecting means selects delayed data from the first delay means in other cases.

Abstract: An analog to digital converter comprising at least two analog to digital conversion engines and a controller for controlling the operation of the analog to digital conversion engines such that during a first phase of an analog to digital conversion process the engines collaborate such that a plurality of bits can be determined during a single trial step; and during a second phase of the analog to digital conversion the conversion engines work independently; and the controller receives the outputs of at least one of the conversion engines and processes them to provide an output word.

Abstract: An offset error, an amplitude error, a phase error and a third harmonic component contained in two-phase sinusoidal signals are removed using relatively simple digital computations. An offset error contained in two-phase sinusoidal signals with a phase difference output from an encoder is detected and corrected. Then, an amplitude error contained in the offset-corrected two-phase sinusoidal signals is detected and corrected. Subsequently, a phase error contained in the amplitude-corrected two-phase sinusoidal signals is detected and corrected. Further, a third harmonic distortion contained in the phase-corrected two-phase sinusoidal signals is detected and corrected. Each correction step includes detecting an error from an ideal Lissajous waveform contained in the corrected two-phase sinusoidal signals, and adding the detected error to an accumulatively added last value to yield a new correction coefficient, thereby dynamically updating the correction coefficient.

Abstract: Devices and methods to test high speed analog-to-digital and digital-to-analog signal converters are provided. According to one embodiment, a testing device can comprise an output, a mixer, and an input. The output can provide a signal, and the mixer can receive the signal and provide a test signal to a data converter having a sampling frequency. The test signal can be spectrally impure. The input can sample the data converter output at a frequency less the sampling frequency so that the data converter output is under sampled. According to another embodiment, a first set of data converters are tested to obtain a mapping function that relates dynamic specifications to device signatures. Then a second set of data converters can be tested and based on their device signatures mapped with the mapping function, dynamic specifications for the second set of data converters can be obtained. Other embodiments are also claimed and described.

Abstract: A compact and highly accurate A/D converter includes series-connected computation cells, the number of which is equal to the number for bits in an output signal. The first computation cell includes a first comparison unit for subtracting a reference current from a first input current to generate a first current, and a second comparison unit for subtracting a second input current from the reference current to generate a second current. The second computation cell includes first and second comparison units having the same configurations as those in the first computation cell. The computation cells of latter stages have the same configurations as the second computation cell. Current mirror circuits included in the first and second comparison units of each computation cell generate the first and second currents. Each computation cell outputs a current having an absolute value in accordance with one of the first and second currents.

Abstract: An analog-to-digital converter error detector suitable for single-chip control loop applications employs a single comparator determining the difference between an initial input voltage and a reference voltage in one or more conversion iterations, with the difference reduced in nonlinear steps during each conversion iteration based on the ratio between sampling and discharge capacitances. The number of conversion iterations required to reduce the initial input voltage to below the reference voltage is counted as representing the difference, with output codes representing the conversion iteration count having a step size increasing with the count value and selected to reduce downstream processing.

Abstract: A multi-channel analog-to-digital converter system includes an array of sub-analog-to-digital converters wherein within the array of sub-analog-to-digital converters, there is at least one designated reference analog-to-digital converter. The analog-to-digital converter system also includes a non-sequential channel select circuit to control a selection of the analog-to-digital converters and the reference analog-to-digital converter to non-sequentially interleave the outputs of said analog-to-digital converters and said reference analog-to-digital converter. Each channel of the plurality of sub-analog-to-digital converters includes a timing skew estimation circuit. Each timing skew estimation circuit receives an output signal from the reference analog-to-digital converter and receives the output signal from the associated analog-to-digital converter.

Abstract: Circuits and methods to achieve a low-noise and low offset continuous sigma-delta modulator used e.g. for battery management are disclosed. Continuous integration of input is enabled by special switching principle of three parallel integrators. Precharging of integrator output in so called pre-run mode minimizes integrator leakage and non-ideal effects by connecting a Gm in pre-run mode either to input voltage or to a reference voltage depending this Gm is being used in a following clock period. Parasitic effects due to switching at first integration capacitor are minimized by using buffer amplifiers tracking the voltage on integration capacitors.

Abstract: A system for spur cancellation comprises an input, an output, a memory, and a summer. A value corresponding to an energy level of a spur is stored in the memory. The summer is configured to receive an input signal from the input, to receive the value from the memory, to subtract the value from the input signal, and to convey an output signal to the output. The output signal is a difference of the value subtracted from the input signal.

Abstract: Systems for providing driving voltage of display panels. An exemplary system comprises a data driving circuit with a plurality of driving units generating analog voltage to drive corresponding pixels according to digital data signals from a data bus, each comprising a temporary storage unit storing N digital data in sequence according to N control signals in a first period and outputting the N digital data in sequence according to M switching signals in a second period; a digital-to-analog (DA) conversion unit converting the N digital data to N analog voltages in sequence; an analog buffering unit buffering the N analog voltages from the DA conversion unit; and a de-multiplexer outputting the N analog voltages to the corresponding pixels selectively according to an enabling signal.

Abstract: A digital-to-analog converter generates a monotonic sequence of reference voltages and selects an arbitrary pair of reference voltages, adjacent in the monotonic sequence. One of the selected reference voltages is supplied through a resistor and a switching device, connected in series, to the output terminal of the converter. The other selected reference voltage is supplied through another resistor and another switching device, connected in series, to the same output terminal. This arrangement saves space, and enables variations in the output voltage levels to be kept within tolerance by use of resistors with sufficiently high resistance values.

Abstract: A system, apparatus and method for providing a digital variable resistor with high resolution and efficient use of substrate area is described. In one embodiment of the invention, a digital variable resistor string comprises a serial array of resistors that is connected to a parallel array of resistors through a switching network. A compensation network is coupled in parallel to the parallel array of resistors in order to compensate for resistance drift caused by non-linear responses of components within the variable resistor. For example, the compensation network may interpolate the digital variable resistor to a preferred resistance value that is within an error margin tolerance.

Abstract: A gray scale voltage generating circuit includes a first resistor ladder circuit, connected between a high voltage power supply terminal and a low voltage power supply terminal and having nodes for outputting respective reference voltages, a second resistor ladder circuit, connected between the high voltage power supply terminal and the low voltage power supply terminal, and plural voltage follower circuits, connected between the respective nodes of the second resistor ladder circuit and the respective nodes of the first resistor ladder circuit with first resistor provided between the n/2'th node voltage and the high voltage power supply terminal and a second resistor provided between the n/2+1'th node voltage and the low voltage power supply terminal.

Abstract: An improved clocked data converter with a vibrating microelectromechanical systems (MEMS) resonator. The MEMS resonator is used as part of the clock circuitry of an analog to digital converter or a digital to analog converter. The MEMS resonator may be used as the frequency determining element of an on-chip oscillator, or as a bandpass filter used to clean up an external clock signal.

Abstract: A signal processing circuit and processing method are provided for measuring an analog signal from a photo-detector. Generally, the method includes steps of: (i) sampling and storing a characteristic of the signal at a first predetermined time following a reset of the circuit; (ii) sampling the characteristic of the signal at a second predetermined time following a reset or initialization of the circuit; (iii) determining a difference between the stored characteristic of the signal sampled at the first predetermined time and the characteristic of the signal sampled at the second predetermined time; and (iv) converting the determined difference to a digital value and determining a slope of the signal from the digital value and the difference between the first and second predetermined times. Thus, the measurement of the slope is independent of and substantially unaffected by absolute values of the characteristics measured at the first and second predetermined times.

Abstract: A matching circuit for two-channel Analog to Digital Converters (ADCs) is disclosed in which two ADCs convert analog signals of two channels to digital signals with the same operational characteristics. A bias voltage supplier operates in such a way that analog signals of first and second channels are each converted to digital signals by first and second ADCs, a bias voltage supplier generates a DC bias voltage to set up DC levels of the analog signals of the first and second channels, and a reference voltage supplier generates a reference voltage and supplies it to the first and second ADCs. Therefore, the first and second ADCs convert the analog signals to digital signals with the same operational characteristics.

Abstract: A multiple input AD conversion apparatus includes a first unit AD converter including a plurality of first conversion stages connected in cascade to convert a first analog input signal to a first digital output signal, a second unit AD converter including a plurality of second conversion stages connected in cascade to convert a second analog input signal to a second digital output signal, and an operational amplifier shared between the first conversion stage and the second conversion stage in a time sharing.

Abstract: A method for pipelining an analog-to-digital conversion of an analog input signal into an N-bit digital output signal is disclosed where a multiplexer is used for the selection of pre-processed digital approximation values from a plurality of adders and subtractors. The selection is set after the decoding of the selected digital approximation values. Thus, considerable more time of the total iteration cycle is available for the pre-amplifier to settle at very high operation frequencies.

Abstract: A complementary metal oxide semiconductor (CMOS) image sensor capable of performing an analog correlated double sampling method is provided. The CMOS image sensor includes an image capturing unit for capturing an analog signal corresponding to an image of a subject; an analog-digital converting unit for converting the analog signal into a digital signal by using a ramp signal decreasing in a fixed slope according to a reference clock; a ramp signal generation unit for providing the ramp signal to the analog-digital converter; and a control unit for providing said units with control signals and outputting data to the outside through an interface.

Abstract: The present invention provides a multifunctional input device. The input device includes a functional mode which defines the mode of operation of the input device. Each functional mode includes one or more domain levels with each domain level containing one or more domain-level values. Each domain level-value within each functional mode is assigned to one of a plurality of programmable input keys. The domain-level value assigned to each programmable input key controls the function of that programmable input key within a given functionality and domain level. The present invention also includes a display to indicate the domain-level value associated with each of the programmable input keys within a given functionality.

Abstract: A method and apparatus for limiting the effect of interfering transmission on a Global Positioning System (GPS) receiver is disclosed. A first mode of operation of the GPS receiver is provided wherein the AGC of the receiver is operated in a linear state. A second mode of operation of the GPS receiver is provided wherein the AGC of the receiver is operated in a non-linear state. A first signal is provided indicating a presence of a jamming signal. In response to the first signal the GPS receiver is switched from the first mode of operation to the second mode of operation.

Abstract: A radar system and method for detecting targets using pulse-compressed signals is disclosed. In one application, the systems and methods can be used to detect one or more relatively small targets whose pulse-compressed signals are masked by the time-sidelobes of a larger target's return signal. The method includes an iterative, detect-and-subtract signal algorithm that processes the post-compressed signal to detect multiple targets. Specifically the processing algorithm operates on the post-compressed signal to identify a point spread function (PSF) that corresponds to the relatively large target. Once identified, the PSF corresponding to the largest target in the post-compressed signal is subtracted from the post-compressed signal to generate a residual signal. This residual signal, in turn, includes the PSFs for the other targets. This process of identifying and subtracting the PSF of the largest target in the residual signal is then repeated until all targets are detected.

Abstract: A positioning system includes a passive, isotropic reflecting landmark at a fixed position and a device. The device transmits an electromagnetic pulse having a circular polarization and receives a return signal over a period of time. The return signal includes a reflected pulse from the reflecting landmark. The processes the return signal to isolate the reflected pulse from the return signal and to determine a range from the device to the reflecting landmark. The reflecting landmark includes a first passive reflector, a second passive reflector, and a static structure configured to statically position the second passive reflector at an angle relative to the first passive reflector. The device optionally moves in a particular direction while receiving the return signal, detects a Doppler shift in the reflected pulse portion of the return signal, and determines an angle between the particular direction and a straight line between the device and the landmark.

Abstract: A method and apparatus for generating accurate estimates of a radar target's azimuth and elevation angles for a phased-phased array rotating radar. Scan modulated coherently integrated (SMCI) monopulse curves are generated from a measured one-way transmit antenna pattern and three receive antenna patterns. The SMCI monopulse curves are calculated in advance for the expected beam steers. To utilize the SMCI monopulse curves, two-way Sum, Delta-Azimuth and Delta-Elevation target returns are coherently integrated, the target's monopulse ratios calculated, and the SMCI monopulse curves or polynomials used to calculate the target's U-offset and V-offset sine-space angles, which are added to the radar's beam steer to get an improved estimate of the target's sine-space angular position denoted as Utgt and Vtgt. A coordinate system transformation transforms Utgt and Vtgt to azimuth and elevation angles in a non-rotating coordinate system.

Abstract: A system and method using a multi-element digital beamformer for detection and mitigation of spoofer and repeater threats to GPS that would not be addressed by baseline signal-to-noise (SNR) maximization algorithms is disclosed. GPS correlators and processing are applied to multiple beam outputs to detect and locate spoofer and repeater threats. In the beamformer processing, detected threats can be spatially nulled, even in the presence of traditional high power jamming, by modifying the normal sample covariance matrix to introduce synthetic nulls. A digital complex weighting system multiples each input channel by a complex (gain/phase) weight and adds the weighted channels together to form beams that the GPS receiver can use to reacquire the satellites in use without knowledge of platform attitude or the antenna manifold.

Abstract: A method in a mobile satellite positioning system receiver operating in cold-start mode, including searching for and detecting (310) a first satellite in a constellation of orbiting satellites, searching (320) for a second satellite based on detection probability information for non-detected satellites, the detection probability information obtained using information about one of satellites not detected or the first satellite detected. In one embodiment, the detection probability information is based on a measure of range between the non-detected satellites and the first satellite detected, and in another embodiment the detection probability information is based on a measure of angle between the non-detected satellites and the first satellite detected.

Abstract: Within an antenna array 120, the magnitude and phase of a relationship resulting from propagation delay between a sample taken at a first antenna 1 to a sample taken at a second antenna 2 at a different time is employed to derive a data value for a virtual antenna 3. Sub-patch antennas 203 perturbed in elevation are employed to expand the elevation range of acceptable gain. Multiple arrays each providing a separate radio frequency output are employed with digital beamform steering to a single point, together with low noise amplification at the feed point, to achieve sufficient gain with an acceptable total array size. A modular implementation with fiber transport is preferably used.

Abstract: The location of unmodified wireless assets in a wireless communication network may be identified using time differences of arrivals of a communication sequence at different network receivers. Time-stamping devices may include correlator circuits in parallel with signal decoders to time-stamp communication sequences. Cellular wireless networks may be frequency-multiplexed to increase spatial time-stamping density. Tags may be attached to passive assets to provide location identification information to network devices. Locations of assets broadcasting standard 802.11 radio frequency structures may be identified. Noise inherent in correlating a communication sequence may be reduced by using a selected correlation function.

Abstract: A location system for locating and determining the motion and velocity of a wireless device. The methods include direct inferences about whether a device is in motion versus static based on a statistical analysis of the variation of radio signal strengths over time. The system is trained according to a sparse set of identified locations from which signal strengths are measured. The system uses the signal properties of the identified locations to interpolate for a new location of the wireless device. The system uses a probabilistic graph where the identified locations of the floor plan, expected walking speeds of pedestrians, and independent inference of whether or not the device is in motion are used to determine the new location of the device.

Abstract: Disclosed is an apparatus which reduces the number of phase shifters required in an antenna array. This is accomplished by supplying standing waves from the phase shifters to each of the radiating elements in a column or row. The standing waves in the rows are orthogonal to the standing waves in the columns. Each of the radiating elements combines the applied standing waves, the phases of which determine the angle of the resultant beam.

Abstract: An antenna according to the present invention includes a dielectric layer 102 with an upper surface and a lower surface, a signal line strip 101 provided on the upper surface of the dielectric layer 102, and a grounding conductor portion 104 provided on the lower surface of the dielectric layer 102. The surface of the grounding conductor portion 104 includes a plurality of planar areas, each of which has a size that is shorter than the wavelength of an electromagnetic wave to transmit or receive. A distance from a virtual reference plane to each planar area is adjusted on an area-by-area basis. Thus, an antenna, which can change various antenna parameters such as radiation directivity, gain and efficiency dynamically and adaptively according to incessantly changing propagation environment of radio wave, is provided.

Abstract: An antenna apparatus includes a minute loop antenna and at least one antenna element. The minute loop antenna is provided to be electromagnetically close to a dielectric substrate including a grounding conductor, has a predetermined number N of turns and a predetermined minute length, operates as a magnetic ideal dipole when a predetermined metal plate is located closely to the antenna apparatus, and operates as a current antenna when the metal plate is located apart from the antenna apparatus. The antenna element is connected to the minute loop antenna, and operates as a current antenna. In the antenna apparatus, one end of the antenna apparatus is connected to a feeding point, and another end of the antenna apparatus is connected to the grounding conductor of the dielectric substrate.

Abstract: A portable communication device includes a radio circuit for feeding antenna elements, at least one component which is mildly sensitive to external radio transmission, and an antenna arrangement for sending and receiving radio traffic. The antenna arrangement includes a first antenna element located within and extending through a major portion of the device, and a second smaller antenna element connected to the first antenna element. The radio circuit is connected between the two antenna elements and the component is provided on a section of the antenna arrangement making small contributions to the antenna currents in the antenna arrangement.

Abstract: A first member is formed with a hole having an inner wall formed with a recess at a first circumferential position. A second member is formed with an elastic retainer which is retractably projected from an outer peripheral face of the second member and engaged with the recess when the second member is fitted into the hole. A chamfered portion is formed on an aperture edge of the hole at the first circumferential position, so as to have a width allowing the retainer to pass therethrough when the second member is fitted into the hole.

Abstract: An antenna assembly includes a base board having upper and lower surfaces, each of which defines a grounding domain and a dielectric domain, a first metal layer disposed on the grounding domain of the lower surface and a second metal layer disposed on the grounding domain of the upper surface, an antenna unit fabricated on the dielectric domain of the upper surface of the base board, and having an antenna body; and a plurality of conductive through holes formed through the base board for connecting electrically the first and second metal layers, thereby permitting coupled current flow generated in the second metal layer to flow into the first metal layer. A slot of predetermined length is formed through the first metal layer for enhancing effective coupled current flowing into the first metal layer.

Abstract: A composite antenna and method for tire monitoring systems is configured as a core composed of polymeric material and a conductive metallic layer in intimate surrounding contact with the core. The polymeric material provides elasticity to the core to enable the core to elongate when subjected to stress forces within a tire. The conductive layer is fabricated from a low impedance material and may be configured as a composite wherein an inner base metal is selected as a strength member and an outer metallic layer is applied to the base for electrical performance enhancement.

Abstract: A system and method for automatically positioning an antenna aperture on a mobile platform in a manner to avoid blockages created by other components/subsystems on the mobile platform between the line of sight of the antenna aperture and a satellite and to avoid interference with other systems that share the mobile platform. In one embodiment, one or more linear support elements are moved by one or more corresponding motors to allow the antenna aperture to be re-positioned between a plurality of different positions. Methods for creating and using a blockage database are also disclosed.

Abstract: An antenna is provided for acquiring RF signals from various satellite ranging systems including GPS, GLONASS, GALILEO and OmniSTAR®. The antenna configuration includes a radiating structure of multi-arm spiral slots terminated with fractal loops. A leaky wave microstrip spiral feed network is used to excite the radiating structure of the antenna. The fixed beam phased array of aperture coupled slots is optimized to receive a right hand polarized signal. The proposed antenna is made out of a single PCB board. The antenna has a very uniform phase and amplitude pattern in the azimuth plane from 1.15 to 1.65 GHz, therefore providing consistent performance at GPS, GLONASS, GALILEO and OmniSTAR® frequencies. The antenna also has a common phase center at the various frequencies from 1175 MHz to 1610 MHz and substantially the same radiation pattern and axial ratio characteristics.

Abstract: Directional wire antennas for use in article or personal tracking and/or inventory monitoring or control systems wherein the antennas are specifically configured to provide a tunable vertical beam angle which is less than their horizontal beam angle. The antennas are modified or non-balanced dipole or monopole structures having non-symmetrical wire legs wherein at least one leg has segments extending angularly in a linear manner in two separate planes. In preferred embodiments the antennas are designed to receive signals from active RFID (radio frequency identification) tags placed on objects to be monitored within confined or defined structures without bleed over of signals from tags placed on objects at different vertical levels of the structure.

Abstract: Antenna arrays which can work simultaneously in various frequency bands thanks to the physical disposition of the elements which constitute them, and also the multiband behaviour of some elements situated strategically in the array. The configuration of the array is described based on the juxtaposition or interleaving of various conventional mono-band arrays working in the different bands of interest. In those positions in which elements of different multiband arrays come together, a multiband antenna is employed which covers the different working frequency bands. The advantages with respect to the classic configuration of using one array for each frequency band are: saving in cost of the global radiating system and its installation (one array replaces several), and its size and visual and environmental impact are reduced in the case of base stations and repeater stations for communication systems.

Abstract: An antenna. The antenna comprises a convex ground unit, a radiating member disposed above the ground unit and a feed member connected to the radiating member. The radiating member comprises a first sub-radiating member and a second sub-radiating member having a feed point to which the feed member is connected.

Abstract: An electromagnetic radiation interface is provided that is suitable for use with radio wave frequencies. A surface is provided with a plurality of electrically conductive bristles. A corresponding plurality of termination sections are provided so that each bristle is terminated with a termination section. The termination section may comprise one or more different termination packages for operating on received electromagnetic radiation and/or producing desired reflections and transmissions. In one embodiment, switches and termination packages may be implemented within integrated circuits wherein the switches may be utilized to switch between different termination packages. The termination packages may include selected fixed reactances and/or modulators designed to produce desired reflections, e.g., Doppler effects to make it appear the surface of the interface is moving a speed different than the actual speed.

Abstract: A method and apparatus for a multiband frequency distributed circuit apparatus with FSS. The apparatus includes a circuit, a first dielectric layer, a first FSS layer, a second layer and a ground plane. The first dielectric layer is operatively coupled to the circuit. The first FSS layer is operatively coupled to the first dielectric layer and is capable of passing a first frequency band. The second layer is operatively coupled to the first FSS layer and includes a dielectric material. The ground plane is operatively coupled to the second layer. A method for implementing a multiband frequency distributed circuit is also disclosed.

Abstract: A medical image diagnosis apparatus, comprises an image generator, a display, and a mechanism. The image generator is configured to generate a medical image. The display comprises a plurality of monitors and is configured to display the medical image. The mechanism is configured to change an arrangement of the plurality of monitors with respect to each of the monitors.

Abstract: A three-dimensional image display apparatus includes an image display configured to output image light which arrays a plurality of pixels and has polarization, a lens array arranged in front of the image display, configured to function as lens at light which has a 1st polarization direction, and not to function as lens at light which has a 2nd polarization direction differed from the 1st polarization direction, and a birefringent phase modulator placed between the image display and the lens array and configured to rotate a polarization plane of the image light.