| 摘要 |
<p>A squat position detector includes a means of emitting a beam of light, a means of detecting the beam of light, a means of indicating when the light beam has been obstructed and a means of positioning the light emission and light detection devices. The light emission and light detection devices are mounted separately in free-standing tubular constructions 1,7,10 that allow the height of the light beam to be adjusted by the user. The length of the beam may be adjusted by moving the two halves of the device towards or away from each other. Breaking of the beam ideally produces an audible signal detectable by the user.</p> |
