OPTICAL PICKUP

• Main Authors: WAKABAYASHI SATOSHI, MIYAKE YOSHIO, KASAHARA KUMIO, TATSUMI KENJI, HASHIMOTO TSUTOMU
• Format: Patent
• Language: English
• Published: 09.05.1987
• Subjects: INFORMATION STORAGE; INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORDCARRIER AND TRANSDUCER; OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICS; PHYSICS

PURPOSE:To allow a light source hardly receive the effect of a returned guide light and to improve the utilizing efficiency of the output light of the light source by providing separately a light collection coupler irradiating an output guide light of the light source onto a disc and a light collection coupler leading the reflecting light from the disc to the guide path. CONSTITUTION:The output guide light of the light source 1 is made directly incident to the 1st light collection coupler 4a and the light is irradiated from a direction vertical to the face of the light guide 2 in the progressing direction of the guide light with a little tilt. In providing the disc 5 in parallel with the light guide path 2, the reflecting light from the disc 5 is not returned to the 1st light collection coupler 4a, but made incident in the 2nd light collection coupler 4b, where the light is converted again into the guide light. The returned guide light is split and collected by a rating light collection beam splitter 3 and made incident on 2-split photodetectors 6, 7 and the progressing direction of the returned guide light is the same as that of the light source 1. Thus, the light is not returned to the light source 1 and instable output of the light source 1 by the effect of the returned guide light is not caused.