| 摘要 |
PURPOSE:To make possible range measurement of high accuracy by making use of the self feedback photo effect of semiconductor laser. CONSTITUTION:An optical system 2 condensing the laser light from a semiconductor layser 1, directing the same to the surface to be measured 3 and feeding the laser light reflected by the measuring surface 3 back to the laser 1, a means of modulating the laser 1 with variable frequencies and a means 5 of detecting the laser light output intensity of the laser 1 are provided. From the modulation frequency value of the laser 1 at which the laser light output intensity becomes maximum, the distance up to the measuring surface 3 is measured. |
