DISPERSIVE WHITE-LIGHT COMBINED WITH A FREQUENCY-MODULATED CONTINUOUS-WAVE INTERFEROMETER FOR HIGH-RESOLUTION ABSOLUTE MEASUREMENTS OF DISTANCE

A nonincremental interferometer for the absolute measurement of distan ces is presented. The measuring technique is based on both dispersive white-light (DWL) interferometry and frequency-modulated continuous-wa ve (FMCW) interferometry. The proposed configuration integrates both t echniques in the same interferometer by use of a single laser diode. T his solution enables the results from the coarse measurements from the FMCW interferometer to be combined with the fine readouts from the DW L interferometer. Preliminary experimental results confirm the capabil ity of the system to combine the advantages of the two techniques. (C) 1997 Optical Society of America.