Optical device for an optical network unit and manufacturing method

Abstract

An optical device for use in optical communication optical network units, having an aptitude for efficient production, manufacturing cost reduction and size reduction, comprising: a first CGH element 21 for converting a multiplexed light from the first input terminal 11 into a parallel light beam; a wavelength splitting filter 23 for deflecting a light having passed through the CGH elements according to wavelengths; a second CGH element 22 for directing a first wavelength component separated by the wavelength splitting filter to the first output terminal 12; an optical path splitting means 22 for guiding a second wavelength component separated by the wavelength splitting filter to a desired optical path; a third CGH element 24 for directing a beam of a second wavelength component having passed through one optical path 27 to a second output terminal 18; and a fourth CGH element 26 guiding a beam of the second wavelength component from the second input terminal 17 to the optical path splitting means 24 so as to transmit the beam of the second wavelength component to travel through the other optical path 28 to the first input terminal 11.