Patent ID: 6934478
Filing Date: 2005-08-23
Classification: G02B,H04B

Abstract:
1. A bidirectional optical communication device for carrying out transmission and reception of an optical signal with use of one optical fiber having a curved end face as a transmission medium, comprising: a light emitting element for generating transmission light; a collection member for collecting transmission light emitted from the light emitting element and coupling the transmission light to the optical fiber; and a light receiving element for receiving reception light emitted from the optical fiber, wherein is satisfied when angles of inclination θ fa and θ fb between an optical axis of the optical fiber and the transmission light after entering the optical fiber with a numerical aperture NA at an outermost periphery are expressed as follows: where θ L denotes an angle between an optical axis of transmission light prior to entering the optical fiber and an optical axis of the optical fiber, θ T denotes an angle between a perpendicular line of the optical fiber end face in a position where the transmission light is coupled to the optical fiber and an optical axis of the optical fiber, NA denotes a numerical aperture of the transmission light collected by the collection member prior to entering the optical fiber, n f denotes a refractive index of a core of the optical fiber, and n o denotes a refractive index of space through which the transmission light passes prior to entering the optical fiber.