| 摘要 |
PURPOSE:To make it possible to measure at a high speed the characteristics of a multi-layer film over a wide wave band range by providing a spectroscope for receiving the light having passed through the multi-layer film, an optical detector for detecting the spectroscopic output, and an indicator for indicating the detected output in accordance with the wavelength. CONSTITUTION:The light from a light source 21 is converted by lenses 22 and 23 into a parallel beam, which is introduced from an aperture 25 into a sample 27 arranged in a vacuum bath 24 and evaporated with a dielectric thin film. The light having passed through the sample 27 is converged through an aperture 26 by a lens 28 and introduced into a spectroscope 29. The spectroscopic output of the spectroscope 29 is focused upon the photosensitive surface 32 of an optical detector 33, the output of which is fed to a synchroscope 33 the detected output corresponding to the transmissivity of the sample 17 for each wavelength is displayed. If it is assumed that the light emitting characteristics of the light source 21 are flat within a desired wavelength range, the spectroscopic output of the spectroscope 29 indicates the transmissivity of the sample for each wavelength. Thus, any film thickness can be accurately measured from the relationship between the film thickness and the transmissivity. At the same time, the characteristics over a desired wavelength range can be measured at a high speed. |
