Patent ID: 8320765
Filing Date: 2012-11-27
Classification: G01C,G02B

Abstract:
1. An optical signal transfer device which transfers a signal between a base unit and a rotary unit rotatable around a rotary axis and supported on the base unit, the device comprising: a transmitter system provided in one of the base unit and the rotary unit to transmit a signal; and a receiver system provided in the other of the base unit and the rotary unit to receive the signal from the transmitter system, wherein the receiver system comprising n light receiving portions and a light reception controller, and n is a natural number, wherein the light receiving portions are rotated around the rotary axis relative to the transmitter system by a relative rotation of the base unit and the rotary unit to form a single ring-like light receiving area, wherein the light reception controller processes an electric signal output from each of the light receiving portions, wherein the transmitter system comprises a plurality of light emitting portions, an emission controller which drives the light emitting portions in accordance with a transmit signal, and an optical guide having a plurality of light incident portions facing the light emitting portions, respectively, and the optical guide guides light from the light emitting portions to be emitted to the light receiving area, wherein the transmitter system includes an opposing area in a ring-like form disposed around the rotary axis, and the opposing area opposes the light receiving area and is equally divided into n areas in a circumferential direction, wherein the optical guide guides the light to at least one of the n divided areas as a light emitting area, and wherein the receiver system and the transmitter system are configured such that at least one of the n light receiving portions faces one of the light emitting areas irrespective of a rotary position of each of the light receiving portions relative to the transmitter system.