| 摘要 |
PURPOSE:To obtain a doppler speedometer having a safety mechanism which prevents the ejection of laser beam outside a case body when not used. CONSTITUTION:As for a doppler speedometer, the luminous flux supplied from a light source means 1 is radiated to a transfer body with a prescribed incident angle, and the speed information of the transfer body 7 is detected on the basis of the deviation of the frequency of the scattered light supplied from the transfer body 7. A movable luminous flux shielding member 14 is installed at an arbitrary position in an optical path from the light source means 1 to the transfer article 7, and the outside ejection of the luminous flux from the light source means 1 is controlled. |
