Light receiving device

Abstract

A light receiving device including an optical waveguide medium (optical fiber) for emitting signal light from an outgoing end, and a light receiving element for receiving the signal light by a light receiving surface and converting the signal light into an electric signal. The outgoing end has a surface cut with a blade saw perpendicular to a traveling direction of the signal light, and an index-matching material exhibiting a refractive index larger than 1 but less than a refractive index of the light receiving element, fills between the outgoing end and the light receiving surface. The surface roughness Rz of the end surface of the optical fiber is preferably over 0.04 μm. The formation under this condition may involve the use of the blade saw having an abrasive grain specified by a grain number smaller than #2000. The light receiving element is disposed so that the light receiving surface is oblique to the traveling direction of the signal light. The light receiving device, particularly, a surface packaging type light receiving device is constructed to have a desired low reflection characteristic while attaining the downsizing and a high productivity.

Dependencies are inferred from the claim text.