| 摘要 |
PURPOSE:To make it possible to measure not only a moving direction but also a moving speed even if the moving direction is constant, by utilizing the mutual relation between a speckle pattern obtained by irradiating an object with laser beam and the moving speed of the object. CONSTITUTION:Coherent beam from a laser diode 10 is allowed to irradiate the surface of an object 16 to be measured during movement through a collimation lens 15. The diffused reflected beam generated from the surface of the object 16 to be measured forms a speckle pattern and a part thereof is received by photodiodes 17a, 17b, 17c...17n. The beam intensity distribution of the speckle pattern is converted to electric signals by the photodiodes 17a, 17b, 17c...17n to be inputted to a signal processing part 18. This signal processing part 18 calculates a speed from the mutual relation present between the above mentioned beam intensity distribution and the speed of the object to be measured. |
