Patent ID: 7330616

Claim:
A micromirror element comprising: a mirror body that is arranged on a substrate via a support, the mirror body having a frame and a movable mirror swayably supported by the frame, and the mirror body being formed so as to allow part of incident light to pass through the movable mirror; and a light detecting unit that is arranged on the substrate and detects the light having passed through the movable mirror, wherein the mirror body and the light detecting unit are provided separately from each other; wherein the movable mirror has a light transmitting hole, and part of the incident light passes through the movable mirror via the light transmitting hole, wherein the light transmitting hole has a structure that can keep an effective incident area constant for an inlet of the light transmitting hole used for light incident to the light transmitting hole even when a relative position of the movable mirror to the light incident to the movable mirror varies; and wherein the light transmitting hole has a tapered form in cross section of which area becomes larger from the inlet of the light transmitting hole toward an outlet of the light transmitting hole.