JPH05249337

PURPOSE:To provide the coupling device which decreases the laborious operations to enhance coupling efficiency in coupling of optical parts using a polarizer and executes the coupling without adjustment. CONSTITUTION:The polarizer 20 is formed on the plane in the central part of a silicon substrate 1. A guide groove 3 for a laser and guide groove 4 for an optical fiber which are aligned in optical axes are constituted on the same substrate 1 by holding the polarizer 20 therebetween. A guide 5 for the laser installed with a semiconductor laser and the optical fiber 6 are disposed in the respective guide grooves 3, 4. As a result, the positions of the guide 5 for the laser and the optical fiber 6 are fixed by the respective guide grooves 3, 4 and since the polarizer 20 is integrally formed on the substrate 1, there is no need for aligning the optical axes and adjusting the incident angle of light on the polarizer with high accuracy. The coupling losses are thus suppressed and the coupling with high efficiency at an increased extinction ratio is executed. Since the mechanical strength is high and the mis-registration after fixing is hardly generated, the deterioration in the coupling efficiency is prevented and the high reliability is obtd.