Patent attributes
The present invention relates to a diffractive grating member and to an optical communication module. The optical communication module includes a semiconductor laser; a coupling optical system for coupling a light flux with a wavelength of λ1 emitted by the semiconductor laser to an optical fiber; and two light-receiving elements for receiving at least two light fluxes each having wavelengths λ2 and λ3 emitted from an end surface of the optical fiber. The coupling optical system has a diffractive structure, and the coupling optical system changes paths of light fluxes each having wavelengths λ1, λ2 and λ3 into relatively different directions such that the light flux with the wavelength λ1 emitted by the semiconductor laser enters into the optical fiber and each of the at least two light fluxes each having the wavelengths λ2 and λ3 enters into each of the two light-receiving elements.
