A basic study is performed to measure surface-coated naphthalene thickness using laser. A Naphthalene layer is made on a thin shiny aluminum slice using vapor plating. First, a diode laser is set up vertically above the naphthalene-coated surface and light of the laser is emitted on the surface. The reflected light is detected using a photo diode at an angle of 45 degrees. Second, the laser is set up above an angle of 45 degrees of the naphthalene surface and the reflected light is detected at an angle of 45 degrees on the opposite side of the laser. Furthermore, the experiment using a non-reflected aluminum slice is conducted in the same way.
As a result, it is shown that there is the linear correlation between the naphthalene thickness and the output voltage of the photo diode. The optical method to measure surface-coated naphthalene thickness is laid the groundwork for by this study.