OPTICAL COUPLING UNIT

PURPOSE:To stabilize the operations of a light projecting/receiving block of a portable terminal equipment and, simultaneously to prevent the consumption of a built-in battery by respectively providing a receiving and feeding terminals on the portable terminal equipment and a master device, thereby obtaining the light source projecting/receiving block of the portable terminal equipment from the master device. CONSTITUTION:A positive terminal 16 and a negative terminal 17 to a receiving terminal respectively are provided on a portable terminal equipment A and on the other hand, the power terminal of a collector/distributor B side is connected to a power VCC and a power supply terminal 19 is connected to VGND. Then, a stabilized power VCC is supplied from the collector/distributor B to the portable terminal equipment A. Thus the terminals 16 and 17 for feeding electric power to optical coupling units 11, 14, 20, and 22 are provided on the portable terminal equipment A and the stabilized electric power is fed to the terminal from the master equipment B, such as collector/distributor, etc. Thus, the occurrence of data transmission errors can be reduced by stabilizing the operations and simultaneously the consumption of the built-in battery of the terminal equipment A is prevented.