| 摘要 |
PURPOSE:To make it possible to test the thickness of a film simply, by providing a lighting means, which includes a white light source and lights a body under test, and providing a light receiving means, which receives the reflected light or transmitted light from or through the body under test, which is lit by said lighting means and converts the light into electricity. CONSTITUTION:A white light source 12, a light sending fiber 13, and a lens 14 constitute a lighting means. The lens 14, a light receiving fiber 15, and a light receiving element 16 constitute a light receiving means. Namely, the lens 14 belongs to both light receiving and lighting means. The light, which is inputted to the light receiving element 16 is divided. When the light having specified wavelength lambda'1-lambda'2 is inputted into the light receiving element 16, the light receiving element 16 is driven, and the amount of the inputted light is converted into electricity. Therefore, the output of the light receiving element 16 corresponds to the spectral reflectance of a transmitting thin film 11 in the region of the wavelengths lambda'1-lambda'2. Thus, complicated computing circuits and the like are not required, and the film thickness can be simply tested. |
