A technique for the transmission of digital information over short distances using infra-red radiation

The paper describes a means of transmitting digital information over limited distances, using a gallium arsenide diode as an infra-red source. At the transmitter parallel binary characters are converted to serial form, and used to pulse-modulate the diode. Different widths of pulses represent logical one, and logical zero. Mirrors are employed to confine the energy into a nearly parallel beam, for transmission to the receiver, where the serial pulse train is restored to parallel form. The data may be sent out at speeds up to 100 characters/second.