| 摘要 |
PURPOSE:To measure the laser output during processing even if the reflectivity from a work changes by partly reflecting the output from laser light and the reflected light of the laser light from the work by a beam splitter and measuring the same by using two pieces of detectors. CONSTITUTION:The laser light oscillated from a laser device 1 is reflected by the beam splitter 2 having the reflectivity r0. The energy of r0I0 enters the 1st detector 3 if the original laser output is designated as I0 and the laser light transmitted through the beam splitter 2 is (1-r0)I0. The laser light transmitted therethrough is reflected by the work 4 having the reflectivity R and the energy of R(1-r0)I0 is reflected and is reflected by the beam splitter 2. The energy of r0R(1-r0)I0 enters the 2nd detector for monitoring the reflected light from the work. The measured value I4 of the 2nd detector 5 is computed by an arithmetic unit 6 from the measured value I3 of the 1st detector 3, by which the value of R(1-r0) is obtd. Since the value of r0 is known by the reflectivity of the beam splitter 2, the reflectivity R of the work 4 can be determined. |
