Abstract: A display system with a pointer that is not restricted by wires or sensors. The display uses a spatial light modulator (14) for projecting an image on the screen (20). During a time period when all of the cells of the modulator (14) are in the same state, a cursor projected onto the screen by the pointer is reimaged from the screen to a detector (26), which translates the cursor image into signals for a central processing unit (38). The central processing unit (38) then directs the system as to what tasks are being dictated by the cursor.

Abstract: A protective circuit for a sequentially selecting circuit which selects a series of circuit element electrodes one by one with signals which are generated by a shift register. The invention includes a counter for generating a count output corresponding to the total number of selections made. An input pulse of the shift register is formed according to the output from the counter and the timing pulse and the counter is reset according to the timing pulse and a clock pulse of the selection. With such arrangement when the timing pulse is not generated, the counter will not operate and an effective input pulse to the shift register will not be generated and therefore the shift register will not sequentially read erroneous inputs and a plurality of shift stage outputs will not be generated at the same time. In this manner, the selected circuits, elements, electrodes and drive circuit of power supply will be prevented from being damaged.

Abstract: A liquid crystal display apparatus in which an image to be displayed is written in the liquid crystal cell by irradiating it with a laser beam and in which the image thus written is enlarged and projected on a screen by optical projection means and wherein the invention the amount of energy supplied to a spot in the liquid crystal cell in which an image is to be produced is increased when writing is not and will not be done in immediately preceding and succeeding spots so that the image writing in the liquid crystal cell can be completed within a shorter time.

Abstract: A plasma display panel having cathodes, anodes and trigger electrodes wherein the trigger electrodes correspond to a plurality of discharge electrodes which are sequentially scanned and wherein an insulating layer separates the trigger electrodes and the discharge electrodes and where a constant trigger voltage is supplied until the plurality of discharge electrodes corresponding to the trigger electrode have been activated. In the invention, the trigger voltage is quickly changed and is then returned to an intermediate level within the varied potential difference and the frequency of a trigger voltage pulse is reduced to one by the number of block discharged electrodes so that the power consumption of the trigger electrodes is greatly reduced and since the trigger voltage is returned to an intermediate level erroneous discharges will not be generated between inactive trigger electrodes and the other discharge electrodes to which data voltage pulses are supplied thus producing a high definition display.

Abstract: A method and apparatus for displaying a video picture on a matrix array of light emitting elements form of m rows and n columns of such elements. The video signal, which is comprised of periodic vertical intervals, each containing successive line intervals of video information, is sampled at a rate of n samples during each line interval. The resultant, n sampled picture elements for each sampled line interval in each vertical interval are stored. During a vertical interval, a given light emitting element, such as the i-th element in the j-th row, corresponding to a sampled picture element in a respective line interval, is energized for a duration greater than a line interval and less than a vertical interval as a function of the brightness of the sampled picture element when that sampled picture element is between and black and peak white levels. In a practical embodiment, a storage circuit stores the n sampled picture elements in each line in an m.times.n matrix array of storage elements.

Abstract: A video display system employing a flat display panel of X-Y matrix type, signal sampling means, "write in" and "read out" memory circuits serially connected between the signal sampling means and the display panel, and a novel signal control means connected to the "write in" and "read out" memory circuits wherein the number of lines or leads for distributing signals from the "read out" memory circuits to the display panel and the number of memory devices used in the "read out" memory circuits are reduced substantially.

Abstract: A signal transmitting system including an A-D converter for converting an analog input signal to a digital signal and a D-A converter for re-converting the digital signal to an analog output signal is provided with improved fidelity without increasing the number of digital levels and digital bits in the A-D and D-A converters.