PURPOSE: To make a configuration of a board other than a shield case and a photodetector for horizontally incident light and the same as the configuration for vertically incident light by installing a reflecting board for reflecting incident light to take it into the inside of the shield case.

CONSTITUTION: Incident light is reflected by a reflecting board 8 and is taken into the inside a shield case 2. Accordingly, inside the shield case 2, a photodetector 6 can be installed so as to be able to receive the vertical incident light with the light reception surface up. Accordingly, a configuration of a board 4 and the photodetector 6, etc., other then the shield case and its production process can be made the same for horizontal incident light and vertical incident light.