| 摘要 |
PURPOSE:To reduce the size of the instrument by irradiating the surface of a body to be measured with coherent light from a laser and measuring surface roughness from a speckle pattern formed with the diffuse reflected light of the coherent light. CONSTITUTION:The surface of the body 7 to be measured is irradiated with the coherent light from the laser diode 1 through an optical fiber 6 and part of the reflected light forming the speckle pattern is made incident on a photodetecting element 11 through an optical fiber 8. Then, S/H12 receives sampling pulses at specific intervals of time to sample the output analog signal of the photodetecting element 11, and input respective sampled values to an A/D converter 13. Then, CPU14 stores RAM18 with a light intensity distribution including the speckle pattern and inputs a data table which indicates the correspondence between intensity distribution data on the speckle pattern and surface roughness previously. The surface roughness data is calculated on the basis of the data table, displayed on a display device 19, and recorded on a plotter 20. |
