Abstract

For an optical head in compact disc (CD) system, an optical device called "laser coupler" (LC) has been developed and used in commercially sold players. This device integrates a laser diode, photo detectors and a micro-prism into one small chip.[1] Using integrated devices of this kind, we can make small, light and stable optical heads with less material and production costs. MiniDisc (MD) systems have become popular as a novel audio system. In this system, a 64mm-diameter disc in a cartridge can record and play back 74 min. of compressed audio data or store 140 MB of user data, using magneto-optical (MO) technology. To improve the portability of this MD systems, smaller, lighter and more stable optical heads are necessary. For this reason, several kinds of integrated optical devices, such as laminated prism [2], holographic optical element (HOE) [3,4], have been reported. In this paper we present a new integrated optical device which we call MiniDisc laser coupler (MD-LC). The simple construction of this device allows an easy mass-production.

© 1998 Optical Society of America