Optics: measuring and testing – By dispersed light spectroscopy – Utilizing a spectrometer
Patent
1980-12-12
1983-12-27
Sikes, William L.
Optics: measuring and testing
By dispersed light spectroscopy
Utilizing a spectrometer
356359, G01B 1102
Patent
active
044227647
ABSTRACT:
Interferometer apparatus for measuring the microtopography of surfaces in two dimensions (surface roughness) uses monochromatic light from a laser. A beam splitter divides the light and directs a beam to the surface being measured and another beam to a reflector. The phase of the reflected beam is varied linearly by means which applies a saw tooth wave to an electromechanical transducer on which the reflector is mounted. The beam is focused onto a spot on the surface by a lens which is translated along the surface in two dimensions. The beams from the reflector and the surface are recombined by the beam splitter and the interference fringe detected thus producing an alternating current signal. The waveform is tracked during the rising portion of the waveform and sampled and held during the retrace portion of the saw tooth. Finally, the resulting waveform is filtered to provide an alternating current (AC) output, the phase change of which is a measure of the topography of the surface to a high degree of accuracy, for example, less than one Angstrom (A) vertical resolution and one micron (um) horizontal resolution. The apparatus provides a low cost profile measurement device which is highly accurate.
REFERENCES:
patent: 1879263 (1932-09-01), Huffschmidt
patent: 3796495 (1974-03-01), Laub
patent: 3809481 (1974-05-01), Schindler
Keller et al., "Michelson Interferometer for Detection of Fast Displacements . . . ", Applied Optics, vol. 14, No. 7, pp. 1616-1620 7/75.
Zakharov et al., "A Homodyne Interferometer with Indication of Reversal", Instruments and Experimental Tech., vol. 18, No. 4, pp. 1220-1223 8/75.
Hartman et al., "Development of Nomarski Microscopy . . . ", Proc SPIE, vol. 192, pp. 223-230, 1979.
Koren Matthew W.
Lukacher Martin
Sikes William L.
The University of Rochester
LandOfFree
Interferometer apparatus for microtopography does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Interferometer apparatus for microtopography, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Interferometer apparatus for microtopography will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-945335