PHOTODETECTING DEVICE HAVING MAGNETIC SHIELDING TUBE AND SAFETY WINDOW

摘要

A photo-detecting device having a magnetic shielding tube and a safety window is provided to prevent pollution of a photo-detector from secretion fluid of a life body by using the safety window. A photo-detecting device having a magnetic shielding tube and a safety window includes a photo-multiplier tube(11) as a photo-detector. A variable shutter(12) and a movable lens(13) are sequentially positioned on the entire surface of an incident window(19) of the photo-multiplier tube(11). The entire surface of the movable lens(13) has the safety window. A hood(18) is attached to a part contact with a target. The movable lens(13) and the variable shutter(12) make only bio-photons incident on the photo-multiplier tube(11) through appropriate manipulation. The safety window performs a filter function in such a manner that only a wavelength band of a bio-photon is incident on the photo-multiplier tube(11).