| 摘要 |
<p>A glass plate thickness measuring instrument wherein a beam of radiation is impinged on the glass to provide a pair of beams reflected from the front and back surfaces of the glass plate respectively. The two beams are made to fall on a radiation responsive device in the form of a charge coupled device, which provides pulsed image outputs of the beams in the form of staircase waveforms of a truncated Gaussian distribution. Electronic circuit means, including microprocessor means, are employed to calculate the centre of gravity of an area under both waveforms above a threshold value, and the distance between the respective centres of gravity calculated to provide a measure of the thickness of the material.</p> |
