| 摘要 |
PURPOSE:To measure the displacement of a material to be measured without contact, by deflecting a collimated light beam at a constant speed, receiving the reflected light obtained by scanning the material to be measured in a specified direction by a space filter, and obtaining the signal having a frequency corresponding to the displacement. CONSTITUTION:Light (a) emitted from a light source 1 is made to be a light beam (b) having an appropriate thickness by a collimating lens 2, reflected by a plane mirror 3, and inputted into a rotary multiple-surface mirror 4. Light beams (c), which are reflected by the multiple-surface mirror 4 are made to be the light beams, whose directions are vibrated at a constant speed, and inputted to the surface of a material to be measured 5 obliquely. By the above described vibration, the surface of the material 5 is scanned right and left in parallel with the paper surface by the light. The light beams (d), which are sequentially reflected by the surface of the material 5, are inputted to a space filter 6 and further converted into a electric signals by a light detector 7. A plurality of waveguides 6a are arranged in parallel on the surface of the tip of the filter 5 with an interval being provided. FM detection of the output signal of the detector 7 is performed. Thus the amplitude and the frequency of the vibration of the material to be measured can be observed. |
