Photo detector

摘要

A photo semiconductor element is covered by a cap with an incident window permitting incident light to penetrate through a translucent member. The photo semiconductor element detects a quantity of incident light penetrating through the translucent member of the incident window. The translucent member of the incident window is made of a material capable of suppressing the transmitting light quantity of incident light components having wavelengths less than 700 nm and larger than 900 nm. A photoelectric current output of the photo semiconductor element is controlled by the incident light penetrating through the translucent member of the incident window. The photo semiconductor element operates in multiple ways as a thermosensing sensor and a photosensing sensor.