Abstract: The analog driver for a display device which is controlled by current, such as an LED, includes a strobed analog input which charges a storage capacitor. The voltage across the storage capacitor is fed to the positive input of a comparator. The negative input of the comparator receives the voltage from a feedback resistor which is in series with the drive voltage, the drive FET (with a gate connected to the output of the comparator) and the light emitting device. Additionally, a reset FET is provided in parallel with the storage capacitor. Displays can be manufactured by a series of panels, each of the panels including an array of these drivers and light emitting devices, along with appropriate control circuitry.

Abstract: The analog driver for a display device which is controlled by current, such as an LED, includes a strobed analog input which charges a storage capacitor. The voltage across the storage capacitor is fed to the positive input of a comparator. The negative input of the comparator receives the voltage from a feedback resistor which is in series with the drive voltage, the drive FET (with a gate connected to the output of the comparator) and the light emitting device. Additionally, a reset FET is provided in parallel with the storage capacitor. Displays can be manufactured by a series of panels, each of the panels including an array of these drivers and light emitting devices, along with appropriate control circuitry.

Abstract: The device is a display apparatus which includes an array of tiles. Each tile includes an array of phosphor pixels sealed between an upper sheet of glass and a metallic anode film. Row control gates form an electrode for each row of pixels. Column electrodes are directed to apertures in the row control gates which are positioned under the electrodes. By maintaining the metallic anode film at a high positive potential, and the electrodes at a positive potential, the pixels can be selectively displayed by selectively holding the column electrodes to a zero potential thereby causing electrons to be projected from the column electrode to the metallic anode film.

Abstract: The apparatus is an interface to convert an input analog video signal (real-time) into an output to drive a matrix of light-emitting-diodes. Alternately, a digital video signal can be received, bypassing the analog-to-digital converters. The apparatus is readily configurable to various sizes of matrix sizes and uses a logic board to arrange the data so that low speed components may be used. Two frame buffers alternately receive data in random access order in accordance with the physical and data format of the LED display, and output data by direct memory access methods.

Abstract: An electronic display unit according to this invention is formed of a plurality of display elements arranged in a two dimensional array. The display elements are selectively activated to generate a message. All the preselected display elements are activated and deactivated simultaneously. The message may be moved vertically or laterally across the array. A memory element is provided for activating each display element. Preferably the information from each memory element is simultaneously shifted laterally to an adjacent memory element while the display elements are disabled.A buffer is provided as an interface between each display element and the corresponding memory element. The intensity of each display element may be controlled by varying the power supply level to the buffer.

Abstract: An automatic teletypewriter is provided. The teletypewriter includes a keyboard having alpha and numeric characters and includes means to utilize the numeric character keys for dialing into the telex network. The teletypewriter also automatically keeps count of the characters generated on each line and generates a carriage return-line feed signal at the end of each line if not directed to do so.