Patent ID: 7615192

Claim:
An ozone gas measurement apparatus comprising: a light-emitting unit; a light-detecting unit; a sensing element; and a signal processing unit, wherein said light-emitting unit emits light having a predetermined wavelength, said sensing element is interposed between said light-detecting unit and said light-receiving unit, and comprises a porous material, and a dye which is deposited in a pore of the porous material, wherein the porous material is transparent, and wherein a thin water film is formed in the pore, and changes in a light absorption characteristic of a visible region upon reaction with ozone gas, said light-detecting unit comprises a light-receiving surface arranged to face said light-emitting unit, receives, via said sensing element, light emitted by said light-emitting unit, and outputs a signal corresponding to a light quantity received by the light-receiving surface, and said signal processing unit calculates an ozone gas amount on the basis of the signal output from said light-detecting unit and a light absorption characteristic, obtained in advance, of said sensing element which contains the dye before reaction with the ozone gas.