| 摘要 |
<p>A reflective surface (1b) which is inclined with respect to the rotation axis (1c) of the rotary shaft (1a) of a rotary body (1) which is an object to be measured is formed on the tip of the rotary shaft (1a). A light beam is applied to the reflective surface (1b) by a light beam emitting unit (2) in a direction along the rotation axis (1c). After the rotation of the rotary unit (1) is started, light reflected by the reflective surface (1b) is detected by a plurality of photodetectors of reflected light detectors (3) which are installed on the same circle whose center is the rotation axis (1c). The time from a reference time till the time when reflected light is detected by each photodetector is measured by a rotation angle time information measuring unit (4) as time information on the rotation angle of the rotary unit (1). By calculating the rotation angle time information with an arithmetic unit (6), accurate information such as the angular velocity, angular acceleration, torque and energy can be obtained over the rotation angle of the rotary unit (1).</p> |
