| 摘要 |
<p>PROBLEM TO BE SOLVED: To reduce the cost of an oil film detector by eliminating the need of using an expensive polarization beam splitter when oil film is detected. SOLUTION: This oil film detector is provided with a polarizing film 16 which reflects two light beams from LEDs 1 and 2 at the same position on the surface 6 of water and only transmits the P-polarized light component of reflected light which is parallel to the surface 6, another polarizing film 17 which only transmits the S-polarized light component of reflected light which is perpendicular to the surface 6, and photodiodes 13 and 14 which work as measuring means to measure the reflected light rays from the surface 6 transmitted through the films 16 and 17. The detector is constituted to detect the presence/absence of an oil film on the surface 6 by means of a signal processing means 15 by utilizing the light quantity ratio between the reflected light rays. Consequently, the detector does not require any expensive polarization beam splitter.</p> |
