To provide an optical sensor system capable of measuring and detecting information on various parts in a device at one location by combining a liquid crystal shutter and an optical fiber array for an optical sensor, improving maintainability by uniting a detector and suppressing the effects of electromagnetic wave by using light for measurement.

In the optical sensor system detecting infrared light, an optical fiber array (7) transmitting infrared light which is wired to a plurality of measuring objects, a shutter (6) which consists of the liquid crystal cell (4) arranged with electrodes (5) and is selectively transmitting infrared light introduced by way of the optical fiber array (7) and the optical fiber sensor (1) for sensing the infrared light having transmitted through the shutter (6) are provided. With this constitution, a plurality of infrared light signals are individually selected and measured. Also, a lens (2) for transmitting and condensing infrared light and a filter (8) for transmitting only infrared light are provided.