Optical device for use in detecting the wavelength and intensity of light

摘要

An optical device capable of detecting the intensity and wavelength of light from a light source (LD) with a high level of precision, and an optical module (101) incorporating the optical device (1). The optical device (1) has a planar lightwave circuit (10) having a Y-branched core (16), a silicon substrate (20), a filter block (30), an optical fiber (40), and a first and a second photodiode (PD1, PD2). The end portion (16a) on the input side of the core (16) is connected to the optical fiber (40). One end portion (16b) on the output side of the core (16) is connected to the filter block (30), and the other (16c) on the same side is to the second photodiode (PD2). The light is divided at a predetermined ratio at the Y-branching portion (16h). One of the branched light is sent through the filter block (30) to be input to the first photodiode (PD1), and the other branched light is directly input to the second photodiode (PD2).