| 摘要 |
PURPOSE:To constitute an optical tuner by a simple structure, and to manufacture new optical parts being suitable for an optical wavelength multiplex transmission of a broadcasting type, by providing a rotary mechanism on a plane linear diffraction grating, and also, providing one piece of photodetector. CONSTITUTION:Five different signals from an input optical fiber 3 are superposed on a light beam consisting of five different wavelengths, and its light beam is made incident on a plane linear diffraction grating 1 through a lens 2. As a result, the light beam consisting of five different wavelengths is subjected to a wavelength dispersion and reflected at a different angle at every wavelength, and also, condensed by the lens 2, only one wavelength in the light beam whose wavelengths are different from each other forms a focus on the end face of a photodetector 4, and the light of other wavelength is not made incident on the photodetector 4. Accordingly, at the time of photodetecting the light beam of other wavelength, the plane linear diffraction grating is brought to a rotational operation by using a rotary mechanism 5, and the light beam of a necessary wavelength is made incident on the photodetector 4. In such a way, an optical tuber can be constituted by a simple structure. |
