| 摘要 |
PROBLEM TO BE SOLVED: To provide a light sensor that can accurately measure ultraviolet light by a constitution wherein the light sensor is provided with a mechanism for generating an inert gas by using an atmospheric air and a space between an ultraviolet light sensor and an ultraviolet light source is filled with the generated inert gas to cause the space to be in an inert gas atmospheric condition. SOLUTION: The ultraviolet light sensor 23 disposed in a casing 20 detects ultraviolet light. The casing has an inner space K and an opening 21 for allowing the inner space to communicate with the outside is formed at a tip of the casing. The ultraviolet sensor is disposed at a position facing the opening of the inner space. The casing has an ambient air suction hole 24 for sucking the ambient air and an ejection outlet 25 for ejecting a gas toward the inner space. A gas flow path 26 is interposed between the gas suction hole and the ejection outlet, and is provided with a pump 27 for sucking the gas through the ambient air suction hole and ejecting the gas through the ejection outlet and an inert gas generation means 29 for generating an inert gas while removing oxygen from the gas flowing in the gas flow path. COPYRIGHT: (C)2010,JPO&INPIT |
