Abstract: An image system includes a beam generator and a screen having a region with an adjustable brightness. The beam generator directs first and second electromagnetic beams onto the region. The first beam changes the brightness of the region according to a first polarity and the second beam changes the brightness of the region according to a second polarity. Such an imaging system can generate a video frame on a projection screen such that each pixel of the frame is “on” for the same or approximately the same amount of time as each of the other pixels. This technique prevents portions of the image from appearing visibly dimmer than other portions. It also allows the persistence of the screen regions to be relatively long, e.g., longer than the frame rate, and thus allows the screen to display/project relatively high-quality video frames.

Abstract: An optical image system includes an image projector and an image generator. The image projector has regions with adjustable brightness levels. The image generator generates an image received from a remote location on the image projector by directing first and second electromagnetic beams onto the regions of the image projector. The first beam changes the brightness levels of the regions in a direction, and the second beam generates the image by changing the brightness levels of predetermined ones of the regions in an opposite direction. Such an image system can capture, transmit, and display an image using an optical signal without converting the optical signal into an electrical signal and back again. Thus, the image system often provides a higher-quality image than conventional electro/optical image systems.

Abstract: Picture display device (1) comprising a cathode ray tube (2) whose display screen (4) is provided with parallel image lines (10) along which an electron beam (5) is scanned, and with pairs of first and second phosphorescent index elements extending along opposed sides of each image line (10). The device also comprises a pair of photodetectors (31,32) for generating index signals indicative of the amount of irradiation by the electron beam (5) of said index elements. An error signal is constructed based on a difference of said index signals for correcting the shape and/or the position of the electron beam (5) on the screen. The index signal of one of the photodetectors is indicative of the amount of irradiation of both the first and the second index elements (11, 12), which improves the detection efficiency of said detector and the signal/noise ratio of its index signal. This results in a better error signal and thus in a better image quality.

Abstract: An spot position indication signal (A) is generated by an address generator (4). A deflection current (Ih,Iv) for deflecting an electron beam spot in one direction in a raster scanned cathode ray tube (2) has a shape for obtaining an approximate linear scan in the one direction. The address generator (4) supplies an spot position indication signal (A) which is related to the spot position if: the spot position indication signal (A) is a linear function in time: A(t)=A0+dA.t, and two predetermined (desired) addresses (A1,A2) occur at two selected levels (I1,I2) of the deflection current to which belong two positions on the picture tube screen.

Abstract: A high frequency arc lamp power supply (518) and display system (500). The power supply (518) drives an arc lamp (504) at a frequency high enough to several times higher than the display system's LSB frequency. By pulsing the lamp many times during each LSB period, the variations in light output during the pulses are all integrated in each bit period and do not degrade the quality of the image display. This eliminates the need for the controller (514) to synchronize the arc lamp power supply (518) with the spatial light modulator (502) when using pulse width modulation.

Abstract: This invention relates to a circuit for solving a vertical interlace phenomenon generated by the instability of servo control when a mode of VCR operation is fast or still, comprising a vertical pulse delay 101 for delaying a vertical pulse inputted from a vertical and horizontal oscillator 100 for the time of a certain horizontal lines, a vertical driving part which transforms the vertical pulse delayed from the vertical pulse delay 101 into a vertical a tooth wave pulse, and amends the transformed vertical a tooth wave pulse according to the vertical position signal inputted to be made relayed as a feedback, a vertical deflection amplifying part for amplifying the amended a tooth wave pulse inputted from the vertical driving part 102, a vertical position detecting part 105 for detecting a vertical position of a picture from the signal inputted from the vertical deflection amplifying part 103 through a vertical deflection coil 104, a Micom 106 for controlling an operation of the vertical pulse delay 101 and

Abstract: It is known to provide a large screen area using a picture tube having a plurality of guns. The object is to provide a transition of continuous brightness, so that the partial picture transitions are no longer perceptible.This is achieved in that a picture tube without a shadow mask, but with optical sensors, index regions and optical walls is employed, so that a precise detection of the beam is possible and the partial picture transitions are no longer perceptible.Especially for television receivers and monitors.

Abstract: A single gun color cathode ray tube (CRT) having a screen consisting of alternating red, blue and green vertical phosphor strips in groups of three, with strips of conductive or photovoltaic material overlaying each phosphor strip, or placed between adjacent strips. The same color conductive strips are connected in parallel in three arrays, and connected to three individual trigger buses. The conductive lines are connected to a positive bias voltage such that when the electron beam within the CRT strikes a conductive strip, a pulse is generated and fed to the corresponding trigger bus. As the single electron beam scans the screen, trigger pulses are generated in the conductive strips and are fed to a trigger pulse amplifier and then to a multiplexer and used as control signals.

Abstract: The invention concerns the measurement of the radiant density of electron beams from shadow mask tubes. According to a known process, the beam is displaced on the screen and pictures are taken of the light spot areas, as they are detected by the effect of apertures when the beam has been displaced. The pictures are then evaluated with respect to their luminance distribution. This process requires an extraordinary number of adjustments.