Abstract: A method and display system for using the light (110) passing through the spokes of a color wheel (100). The light is a mixed and rapidly changing color. Adding all of the spoke times produces white, but adding a subset creates color artifacts. The spoke times cannot all be added at the same time without altering the white point of the display. The spoke times are added in a sequence and the sequence is altered over time for the same pixel such that the pixel converges to white over time. The pattern of spoke bits is arranged so that as adjacent spoke bit pixels are added, the net spoke light converges to white. The patterns are also varied so that as more and more spoke bit periods are turned on, the net spoke light converges to white. Each spoke bit period adds n-LSBs of white light intensity, so as each spoke bit period is added, n−1 LSBs of white light are subtracted from the white data.

Abstract: In a scrolling color projection system for displaying images represented by continuously updated frames of information, eg., video images, and employing a single, reflective electro-optic light modulator such as an AMLCD, flicker in the image caused by asymmetric electrical behavior of the light modulator is reduced without substantially reducing the brightness of the display, by addressing the modulator array at least twice during each frame period.

Abstract: In a single panel scrolling raster projection system of the type having a single light source, a single light valve panel, a rotatable element having surface segments for separating the white light into color bands, and field-sequential, line-at-a-time addressing means, one or more of the color bands is sized to have a height in the scrolling direction greater than the height of the panel in the scrolling direction, and sizing the remaining bands to have a scrolling height substantially equal to that of the panel. Color correction is achieved by changing the power of the light source to increase or decrease its illumination during the period in which the panel is substantially entirely illuminated by a color band having a scrolling height greater than that of the panel, and/or by adjusting the scrolling heights of the color bands relative to one another.

Abstract: An imaging system, comprising a broadband unpolarized white light source (81), a polarization converter system for converting polarization axes of unpolarized white light into a substantially single polarization axis, to produce a beam of polarized light, a selective polarization filter (82), adapted to selectively rotate a polarization axis of a selected spectral band of light of the with respect to remaining polarized light based on a control signal (119), a polarized beam splitter (84), for separating light having a the substantially single polarization axis from light having a rotated polarization axis, a pair of electro-optic spatial light modulators (86, 89), disposed along a path of light within the spectral band and a path of remaining light outside the spectral band, respectively, and being adapted to modulate an image therein, and a polarized beam splitter (88), for recombining modulated light from the pair of light modulators.

Abstract: A system for displaying a color broadcast television signal is provided. The system employs a cathode ray tube (CRT) which has only one electron gun and does not have a mask. The faceplate of the CRT has red, green, and blue phosphor stripes which form triads. A beam positioning gap, which may be patterned, is associated with each triad. By scanning the tube's electron beam along the beam positioning gap, vertical position information is obtained which is then used to accurately position the beam on the phosphor stripes as the stripes are scanned. Flyback of the electron beam can be avoided by scanning the phosphor stripes and the beam positioning gap in a serpentine pattern.

Abstract: A tone display method is provided that can prevent image quality deterioration of the dynamic image and can avoid a cost increase. When an image with 256 tones is displayed, one field is divided into 37 subfields for one color. Among the 8 bits corresponding to the 256 tones, the six high-order bits from the third bit are displayed by means of time width modulation using 35 subfields SF3-SF37 having weights of ““4” and “8”. The two low-order bits are displayed on a binary base using two subfields SF1 and SF2 whose weights are “'1” and “2”, respectively.

Abstract: A system architecture for a display system with electronically controlled optical retarder stacks. The system uses only one spatial light modulator and a color filter to determine what the color of the image created by the modulator will be when projected onto a display surface. In one embodiment, the color filter passes one of red, green or blue light at any give time. The color filter can be placed between the light source and the modulator optics, between the modulator optics and the modulator, between the modulator and the projection optics, or made part of the projection optics itself. The retarder stack for transforming at least partially polarized input light can include a first retarder and a second retarder. The first retarder has a first retardance and a first orientation and the second retarder has a second retardance and a second orientation, both orientations with respect to the partially polarized light.

Abstract: A method of selecting a set of color sources for an image display system, the image display system creating a color image from at least three single-color color sources. According to one embodiment of the present invention, the method comprises selecting a first, second, and third color source. The first and second color sources are divided into a high-efficiency group and a low-efficiency group based on the efficiency of the color source. If the first color source is selected from the high-efficiency group (1102), the second color source may be selected from either the high-efficiency group or the low-efficiency group (1104). If the first color source is selected from the low efficiency group (1102), the second color source is selected from the high-efficiency group (1106). According to one embodiment of the present invention, the third color source is selected (1108) without first sorting the third color sources into high and low-efficiency groups.

Abstract: A display system using red, green, blue, and white light. The system derives data for the white portion of a color wheel or a white device from the red, green and blue data. The white portion of the color wheel is controlled as if it were another primary color on the wheel. Errors are prevented by a correction applied if the unfiltered light from the source has a different color temperature than the white light produced using the red, green and blue segments of the color wheel, or the devices for those colors. Analysis is performed on the data to determine if white light is necessary to be added to each frame of data.

Abstract: In a single path embodiment of a multimedia projector (30) of the present invention, the light emitted from blue, green, and red generally monochromatic LEDs (72) or LED arrays (70) is propagated through optical fibers (76) and then integrated through an optical integrator (40). A display controller (56) receives image data from a personal computer (58) and converts the data to color frame sequential data delivered to a common display device (44). The display controller (56) synchronizes the data with ON/OFF signals conveyed to an LED power supply (34). Because the synchronization is entirely electronic, the frame sequential information can be cycled much faster and more accurately than can be accomplished with a color wheel system (10).

Abstract: This invention provides chromaticity compensation for color filters having nematic liquid crystal tuning elements, as well as fast-transition tuning units for use in combination with chromaticity compensation. The filters of this invention have two stages formed by three linear polarizers in series, as least two of which are color polarizers. Within each stage is a tuning unit comprising a nematic liquid crystal cell switchable between a first state wherein the polarization of light is orthogonally transformed and a second state wherein the polarization is unchanged. In the first state the liquid crystal cell chromaticity introduces significant distortion to the filter stage, but in the second state it does not. Chromaticity compensation is achieved in this invention by optimizing the use of the undistorted normal states and by judicious choice of the design wavelengths of the liquid crystal cells.

Abstract: Training apparatus and method for establishing the network definition function of a trainable processing apparatus for analyzing a signal, includes providing a training sequence having a first signal and a distorted version of the first signal, receiving the training sequence and generating a distortion perception measure for indicating the extent to which the distortion would be perceptible to a human observer, and applying the distortion perception measure to the trainable processing apparatus to determine the network definition function.

Abstract: In a color image display apparatus, a coloring unit consisting of a plurality of color filters is disposed confronting to the display face of a monochrome image display unit. When the color filters are sequentially faced to the display face as the coloring unit is rotated, video signals of the color signals corresponding to the respective color filters are inputted and stored in a plurality of video signal storage units, and the stored video signals are selected by a signal switching device and outputted to the image display unit, whereby a color image is displayed.

Abstract: A system for displaying a color picture. This system has a field sequential signal generator for receiving and storing a color picture signal, which includes a plurality of signal components per field, at a first rate and sequentially sending the plurality of signal components, as a field sequential signal, at a second rate which is higher than the first rate; a picture display for displaying a monochromatic picture based on each of the signal components; a coloring device for coloring light emitted from the monochromatic picture displayed on the picture display; and a controller for sending a vertical sync signal, which includes a plurality of vertical sync pulses corresponding to the signal components respectively, to the picture display.

Abstract: An optical display system includes a light source, a color wheel, an optical train and a light valve. The optical train includes a diffuser element, a compound parabolic concentrator and an integrator. The diffuser element diffuses incoming light to fill in holes in cone half-angle distribution of light generated by the light source. The compound parabolic concentrator reduces the cone half-angle of the diffused light to a cone half-angle expected by the light valve. The integrator reduces hot spots in the diffused light. The color wheel may modulate optical path length of light traveling through the color wheel. Modulating the optical path length reduces coherence in the light generated by the light source. A color wheel that reduces coherence would allow the light source to be laser or LED-based. If the light valve is a ferroelectric light valve, the color wheel may include pairs of polarizers. Light is polarized in orthogonal directions by the polarizers in a pair.

Abstract: A sequential color display system (10) suited to receive data (20) at different rates without discarding or filtering video data. The mismatch of bandwidths between the input source video data and the output sequential color display is accommodated by retaining a modified synchronous operation. A color wheel (50) having a plurality of segments is utilized whereby the input frame rate in reference to the color wheel rate is always a ratio of integers. Using a digital micromirror device (44) spatial light modulator, no mixing of frame-to-frame bit planes is required during a colored segment. In the preferred embodiment, the ratio of integers is 7-to-6 for a 50 hertz input, such as a PAL system, or a 5-to-6 ratio for a 72 hertz input. The color wheel is maintained at about a 60 hertz rate.

Abstract: In a pool lighting system, each illuminator (10) comprises a color wheel 26, a driver mechanism (24) for rotating the color wheel, and a synchronization circuit (42). The synchronization circuit is responsive to an alternating-current source of power applied to the illuminator to control the driver mechanism to place the color wheel at a predetermined position after a predetermined time subsequent to the alternating-current source of power being initially applied to the illuminator.

Abstract: A color control system for projection television displays having a projection lamp, a light valve and a device for varying the color of the light from the projection lamp, such as a color wheel. The color wheel driver provides an output signal which represents the position, that is the color, of the color wheel disposed in the lamp beam. The lamp driver varies the output power used to drive the lamp in response to the particular color of the color wheel disposed in the beam. If the projection lamp has a deficiency in a certain color the present system provides greater output power to the projection lamp during the presence of the filter for that color. A user input control provides for changing the tint of the system based on user preferences and/or any changes occurring in the color filters or projection lamp.

Abstract: A system and technique for directing intensity modulated electromagnetic energy. The inventive system (10) includes an intensity modulated source of electromagnetic energy (12). Individual elements (22) in an array of energy directing elements (15) are activated in sync with the modulation of energy source (12). In a particular implementation, the source (12) is a laser. The intensity of the laser is reduced during each successive field per frame. The energy directing elements (15), in this case--light directing elements, are implemented with an array of digital micromirrors. The light source (12) is modulated in intensity in accordance with a fixed modulation scheme. The mirrors (22) are selectively activated relative to the light source modulation scheme. Hence, the invention provides a gray scale output while allowing the time between mirror flips to be constant.

Abstract: In a color image display system formed of a monochromatic CRT or like image display device (102) having a screen (103) for display of images and a rotary filter (106) comprising color filter sections (106R, 106G and 106B) of a plurality of colors; image signals are read from memories (130R, 130G, 130B) at a rate higher than they are written in the memories, so as to reduce flickers. The problem of passing of the reading address over the writing address is solved by reading the image signal of prominent color taking a period in which the passing over occurs. High frequency components of other color image signals are extracted and added to the image signal of each color to thereby enhance the definition of the picture.

Abstract: The present invention relates to a liquid crystal display system in which a pair of transmission displays are used with a light source, and coupling optics to provide a small, high resolution optically efficient color imaging system. A preferred embodiment of the system comprises a color shutter to control color transmission through each liquid crystal display.

Abstract: A multiple-beam field sequential color (FSC) display system is provided for receiving a stream of digitized single-beam image data to display a color image by employing a plurality of CRT guns to project multiple beams on a monochromatic CRT screen followed by converting a monochromatic refection from the CRT screen to the color image by using a liquid crystal color system (LCCS). The multiple-beam display system includes a multiple-beam image data memory which includes a plurality of data-banks. The multiple beam display system further includes an image data rearranging processor for rearranging and storing the plurality of digitized single-beam image data in the multiple beam-image data memory according to a pre-designated multiple-beam sequence in each of the data-banks.

Abstract: A method for the conversion of conventional interlaced video display synchronization signals to those required for a field sequential color display interlaced video synchronization signals comprises the steps of receiving the conventional horizontal and vertical synchronization signals; multiplying the repetition rates of these signals by a factor that is number of component colors that comprise the colors of the video display; selecting time segments of the multiplied horizontal synchronization signals; phase shifting these selected time segments to align with the multiplied vertical synchronization signal; merging the phase shifted and the non-phase shifted time segments of the multiplied horizontal synchronization signal to form the field sequential color display horizontal synchronization signal; and amplifying and buffering the multiplied vertical synchronization signal and the field sequential color display horizontal synchronization signal to act as input to the deflection circuitry of a field is seque

Abstract: A color image display apparatus utilizing a field sequential signal displays a picture normally without disturbance or deteriorating vertical resolution even when displaying an interlace image signal. The color image display apparatus is formed by a field sequential signal generator for converting a primary color signal to be interlaced into a field sequential signal, a monochrome image display apparatus for sequentially displaying a converted field sequential signal, a color apparatus 5 disposed to face a display screen of the monochrome image display apparatus to color a field sequential signal displayed on the display screen, and a control circuit for controlling timing of operations of these elements. A field judging result is supplied to the control circuit, and the control circuit operates so that a horizontal synchronizing signal of the field sequential signal is outputted continuously in a constant cycle even when an image signal to be interlaced is inputted.

Abstract: A synthetic color television system includes a color-filter for three primary colors and a brightness-sensitive medium. The color-filtering layers for the three primary colors are sequentially excited between the camera and objects taken by the camera so as to regulate the vertical and horizontal scanning signals and the sequence of signals of the three primary colors read from the brightness-changing signal series, or from a digital or analog source of image signals containing the above-mentioned signals transmitted to a displaying screen. A representation of the three primary color filtering screen displays synchronically the picture in the order of the three primary colors, creating a color picture effect through the persistence of vision on the three primary colors.

Abstract: A color image display system (10, 110, 120, 150) having a lamp power supply (78, 134, 152) switching rate being a multiple of, and synchronized to, a video frame rate. An AC component of a lamp driving waveform which may cause variations in intensity of the lamp output is synchronized to the video frame rate. Synchronizing the lamp power supply switching rate to the frame rate stops the beating and rolling of color bands in the video frame that may be produced by a ripple in light intensity. An odd number of switching cycles per two frame periods is chosen to alternate the phase of the ripple pattern frame-to-frame for ripple cancellation through integration. The lamp driving waveform may be amplitude modulated (90) to balance a lamp (14) that has spectral deficiencies. A DMD spatial light modulator (26) is utilized to modulate the colored light and generate a light image on a display (42) in either a sequential, or non-sequential image display system.

Abstract: A method of adjusting color temperature of images displayed by a display system (10) whose images are based on sequential pixel data and are filtered with a color wheel (15, 15', 15"). The relative display times for each color are adjusted to result in a corresponding adjustment of color temperature. In a first embodiment (FIG. 2), the size of the color wheel's segments are changed as well as the display times for data corresponding to each segment. In a second embodiment (FIG. 3), the display times for data corresponding to one or more segments are decreased with a black display time to fill in the difference.

Abstract: A SLM-based projection display system (10) samples and processes video data for delivery to a spatial light modulator (SLM) (13c), and uses a color wheel (14a) to color the SLM-generated images. A frame memory (13b) provides data to the SLM (13c) and is managed so that, if the phase of the incoming video signal changes, a desired phase relationship between the color wheel position and the data available to the SLM (13c) can be maintained. Also, a motor control unit (15a) uses a horizontal sync signal to generate a drive signal for the color wheel motor (16a), which limits the transient time during phase-changing events, and which provides a means for adjusting the phase of the drive signal.

Abstract: In a three lamp, three light valve projection system, the lamps are energized sequentially in a three phase illumination cycle. The light therefrom is separated by an optical system composed of a three by three array of nine mirrors, all but one of which must be dichroic, to produce red, green, blue color sequential illumination of each light valve. Each light valve, which is controlled by a different control signal derived from an input video signal, is illuminated by a different color sequence such that during each phase of the illumination cycle, each light valve is illuminated by a different color. When the output beams from the light valves are converged over the same area of a screen, the phases of the illumination cycle occur at the field rate of the input video signal, whereas, when the output beams are arranged to produce a tiled image, the phases of the illumination cycle occur at three times the field rate.

Abstract: In a color image display system formed of a monochromatic CRT or like image display device (102) having a screen (103) for display of images and a rotary filter (106) comprising color filter sections (106R, 106G and 106B) of a plurality of colors; image signals are read from memories (130R, 130G, 130B) at a rate higher than they are written in the memories, so as to reduce flickers. The problem of passing of the reading address over the writing address is solved by reading the image signal of prominent color taking a period in which the passing over occurs. High frequency components of other color image signals are extracted and added to the image signal of each color to thereby enhance the definition of the picture.

Abstract: A single-panel matrix display has rows of pixels continually illuminated by scanning red, green and blue light bands. The transmissivity of the rows is modulated for each colored light band in turn by sequentially driving a group of closely-spaced rows of the pixels which are about to be illuminated by the color light band.

Abstract: White balance adjustments may be carried out using the same adjustment methods as for a simultaneous system with a field-sequential display method and costs may be reduced because only one amplifier is sufficient for driving the image-receiving tube by constructing an image output circuit for use with a field-sequential display method in such a manner that the gain of a transistor set up using drive adjustment resistors and background adjustment resistors corresponding to red, green and blue is changed over by a switch on the timing of a field synchronization signal using a white balance adjustment circuit.

Abstract: A color display device (10) incorporates three light sources (12) supplying red, green and blue light respectively. A spatial light modulator (20) is positioned to provide time varying selective blocking of light from the sources (12) under television signal control. Light passes from the sources (12) to a condenser lens (16), then through a liquid crystal display element (22) and a projection lens (18) before reaching a screen (30). The display element (22) is also under television signal control. Signals supplied to the display element (22) provide for successive sets of three frames to be displayed, each set incorporating frame information to be displayed as red, green and blue and combinable to form a colored frame. When the element (22) displays a frame corresponding to one of the three colors red, green and blue, the modulator (20) transmits that color and blocks the others. The screen (30) receives a color image in which red, green and blue are displayed successively for each frame.

Abstract: A color image display system includes a monochromatic CRT or similar image display device which includes a screen for display of images and a rotary filter having filter sections of a plurality of colors. The system further includes memories for storing color image signals corresponding to each of the colors. A control circuit reads the color image signals from the memories at a higher rate than the color image signals are written into the memories to reduce image flickering. The reading operation, however, passes over the writing operation. Discontinuities caused by this passing over are reduced by reading a color image signal corresponding to a less prominent color during the passing over. Discontinuities are avoided by providing an additional memory in the system and alternately reading and writing between one of the first set of memories and the additional memory.

Abstract: A liquid crystal light valve (12) is sequentially modulated with images corresponding to three primary color components of a scene at a rate which is faster than flicker can be perceived. A color switching apparatus (20) receives a white light beam from a high intensity light source (18), separates the white light beam into three color light beams of the respective primary colors, and sequentially illuminates the light valve (12) with the three color light beams in synchronism with modulation of the light valve (12) with the corresponding color image components. An optical system (26) projects an image of the modulated light valve surface on a screen (28), such that the three color component images appear to merge together in time and thereby synthesize a full color image of the scene.

Abstract: The present invention relates to a projection type liquid crystal display. In a preferred aspect, the projection type liquid crystal display of the invention includes an optical source for generating light, a light dividing unit which divides the light into a first light having a first polarization direction and a second polarization direction and allows the first and second lights to come out in different directions from each other, a pair of reflective liquid crystal display elements formed of a first reflective liquid crystal display element and a second reflective liquid crystal display element with synchronization, a light synthesizing unit for receiving the first light which comes out of the first reflective liquid crystal display element and the second light which comes out of the second reflective liquid crystal display element and synthesizing the first and second lights into image light, and a screen.

Abstract: An electro-optical system such as an image display system and a method of displaying images are described. Laser beams of three primary colors are emitted from three lasers in a time sharing mode. These laser beams are directed onto the same optical path and then separately given optical information from the same optical modulating device in accordance with images of the respective primary colors. By this structure, displacement of constituent color images can be effectively avoided.

Abstract: A two-channel field sequential display system utilizes both simultaneous and sequential color display methods to display full color images in a way that is less complex, smaller in size and less costly than prior art additive color systems, while exhibiting higher light output and fewer temporal visual effects than prior art single-channel field sequential color display systems. The two-channel field sequential display system displays two of three primary colors that make up the image simultaneously during a portion of a display frame and displays the third primary color sequentially during a subsequent part of the display frame. The two-channel field sequential color display concept may be applied to any projection system which combines individual monochrome projector outputs to form an image on a screen or to any display technique that is capable of superimposing two images.

Abstract: A simplified two-light valve configuration for high performance projection displays which eliminates much complexity and the costs associated with three-light valve projection displays, such as a crossed dichroic beam splitter cube, a long retrofocus projections lens, and the additional cost and complexity of a third light valve. Two reflective liquid crystal light valves are positioned and aligned relative to each other on two adjacent surfaces of a polarizing beam splitter cube. Illumination is introduced through a third face of the cube, and a projection lens images the two light valves through a fourth surface of the polarizing beam splitter cube. Color-sequential and alternating polarization states are provided by a color filter wheel or cage containing individual facets of dichroic or color glass filters, such that as the wheel or cage rotates, the filters change and produce sequential red, green and blue outputs.

Abstract: A color projection video system utilizing only a single light valve. A white light source is separated into into red, green and blue bands. Scanning optics cause the RGB bands to be sequentially scanned across a light valve, such as a transmission LCD panel. Prior to each color passing over a given row of panels on the light valve, that row will be addressed, by the display electronics with the appropriate color content of that portion of the image which is being displayed. The image is projected by a projection lens onto a viewing surface, such as a screen. The device includes circuitry to synchronize the illumination of the light valve with the video signal and to minimize video breakup when changing video sources.

Abstract: A color correction system for a video projection system utilizing a single light valve for modulating light impinging thereon with a video signal and three projection lamps, one for each of the primary colors, which are activated sequentially. Positioned in the light path between two of the lamps and the light valve are occluders which block and unblock the light output from their associated lamp. The lamps which have the occluders are operated such that each lamp may be driven with a series of non-occluded pulses and occluded pulses. The occluded pulses occur when the occluder blocks the light output from the lamp. The more a desired reduction in light output in one of the colors is required, the non-occluded pulses are reduced and the corresponding occluded pulses are increased. This permits adjustment of the colorimetry of the system without adversely affecting the electrical properties of the lamp.

Abstract: A color projection video system utilizing only a single light valve. A white light source is separated into into red, green and blue bands. Scanning optics cause the RGB bands to be sequentially scanned across a light valve, such as a transmission LCD panel. Prior to each color passing over a given row of panels on the light valve, that row will be addressed, by the display electronics with the appropriate color content of that portion of the image which is being displayed. The image is projected by a projection lens onto a viewing surface, such as a screen. The device includes circuitry to synchronize the illumination of the light valve with the video signal and to minimize video breakup when changing video sources.

Abstract: The field image signal for each of the color components of a frame color image signal is formed into a signal of odd number field groups and even number field groups of predetermined color sequence connected together in series, and with the color component sped up several times. The signal is scanned, with the signal of a specific color component deflected vertically by half the horizontal scanning spacing amount, the odd number fields and even number fields being deflected in opposite directions. As a result odd number and even number field images are displayed on the black and white display at respective established locations. At the same time, the light color changing means is driven with a signal corresponding to the color component signal, and the non color light signal displayed in black and white is changed into a light signal of a color component corresponding to the signal. As a result a high resolution color image is displayed without color aberration.

Abstract: A color projection display uses a dichroic cube for modulating the color of light reaching the imaging element of the display. This way, a colored image may be projected by frame sequential technique, but with the use of only a single imaging element.

Abstract: An optical panel 10 includes a plurality of waveguides 12 stacked together, with each waveguide 12 having a first end 12a and an opposite second end 12b. The first ends 12a collectively define a first face 16, and the second ends 12b collectively define a second face 18 of the panel 10. The second face 18 is disposed at an acute face angle relative to the waveguides 12 to provide a panel 10 which is relatively thin compared to the height of the second face. In an exemplary embodiment for use in a projection TV, the first face 16 is substantially smaller in height than the second face 18 and receives a TV image, with the second face 18 defining a screen for viewing the image enlarged.

Abstract: A liquid crystal projector projects an image based on video data inputted from the external.

Abstract: A clear color image having a high contrast ratio without particular coloration is displayed on a screen by improved display apparatus. Such display apparatus is comprised of a spatial light modulator including a photo-conductive layer, a photo-modulator layer and a dielectric mirror, a device for writing color images of different colors onto the spatial light modulator time-divisionally in a sequence of the different colors, a reading device for producing reading lights having different colors in synchronism with time-divisional writing of the color images, and for projecting the reading lights to the spatial light modulator, a driving device for supplying the spatial light modulator with different voltages and frequencies correspondingly with the reading light of different colors and in synchronism with time-divisional projections of the reading lights, and a device for projecting the color images read out from the spatial light modulator on the display device.