| 摘要 |
PROBLEM TO BE SOLVED: To provide a gas concentration measurement device capable of removing the dirt in an optical system without changing the optical characteristics of a window member and a lens.SOLUTION: The gas concentration measurement device includes: a light source part 1 having a laser emitting a laser beam and a light source lens 3; a condensing lens 5 arranged in the light reception side; a light receiving element 6 for receiving the laser beam through the light source lens, a measurement target gas 10, and the condensing lens; a signal processing circuit for measuring the concentration of the measurement target gas on the basis of the output from the light receiving element; a window member 4 provided on the measurement target gas side of at least one of the light source lens and the condensing lens, and having a photocatalyst film 4b formed on the surface in contact with the measurement target gas; an ultraviolet light source 14 arranged at a position not in contact with the measurement target gas, and generating ultraviolet light for activating the photocatalyst film; and an optical member 15 for guiding the ultraviolet light from the ultraviolet light source to the window member. |
