| 摘要 |
PROBLEM TO BE SOLVED: To provide a sensitivity variable type light-integrating element with a low distortion in a wide band such that can surely detect its light signal, regardless of the intensity of the incident light. SOLUTION: A distribution reflecting mirror 3 having wavelength selectivity is provided to the previous step of a waveguide type light-receiving element 2, and a current is injected to the area of the reflecting mirror, which realizes an element structure that can control the transmittance of incident light by the reflecting mirror. In particular, the distribution reflecting mirror is formed of a semiconductor layer, which is formed on a diffraction grid with a cycle ofλ/2 neff, or of a multiplayered film reflecting mirror with a cycle ofλ/2 neff in which a semiconductor plate provided with a waveguide layer is arranged with a low-refractive index layer inbetween, and further a phase shift region ofλ/4 neff is provided in a part of the area of distribution reflecting mirror. |
