| 摘要 |
PURPOSE:To enable measurements free from error and set small the distance of each component from the device by moving a base material relative to a measuring means in the laser intensity modulation distance measuring system, acquiring the sensing data about the height of the component, and comparing the sensing data. CONSTITUTION:A laser beam reflected by a galvano-mirror 4 is passed through an Ftheta lens 5 to converge beams into parallel flux and cast onto a printed circuit board 6 on which a component 15 as measuring object is to be or has been mounted. On the other hand, that flux of laser beam split in two directions by a beam splitter 3 which is directed down inward is led to a high speed photo-diode 9. and the output therefrom is fed to a phase meter 10. The flux of laser beams which is reflected by the mirror 4, led to the circuit coard 6, and reflected by the component 15 is passed again via splitter 3 and left incident on a diode 8 via a lens 7. The output therefrom is fed to the phase meter 10, and the height of the component 15 is determined by measuring the output difference from the diode 9, i.e., the phase difference. |
