Contactless thickness measuring apparatus and measuring method f

Details Contactless thickness measuring apparatus and measuring method f Contactless thickness measuring apparatus and measuring method f

1995-05-12

1997-04-08

Pham, Hoa Q.

Optics: measuring and testing

By configuration comparison

With photosensitive film or plate

356357, G01B 1106, G01B 902

Patent

active

056193297

ABSTRACT:
A contactless thickness measuring apparatus for measuring the thickness of an object includes a light source emitting a variable-frequency light beam, an oscillating center wavelength of which is changeable; an optical device for illuminating the object with the light beam to measure the thickness of the object; a light intensity detecting device for detecting the intensity of light deflected from the object and of light penetrating through the object; a signal processing device for changing the oscillating center wavelength while monitoring the light intensity and containing an amount of phase change from a waveform of a change in light intensity; and an analyzing device for determining an absolute thickness of the object from a relationship between absolute thickness and a phase change amount. In this way, it is possible to measure the absolute thickness of the object without contact using an apparatus having a simple structure by monitoring the object's thickness during its manufacturing process. Furthermore, the apparatus is relatively insensitive to external influences.

REFERENCES:
patent: 3869211 (1975-03-01), Watanabe et al.
patent: 3892490 (1975-07-01), Uetsuki et al.
patent: 4293224 (1981-01-01), Gaston et al.
patent: 4312732 (1982-01-01), Degenkolb et al.
patent: 4618262 (1986-10-01), Maydan et al.
patent: 5101111 (1992-03-01), Kondo
Micro electro mechanical systems, Oison, Japan, Jan. 25-28, 1994, IEEE Catalog No. 94CH3404-1 Kazuyuki Minami et al, pp. 217-222.

Affiliated with

Also associated with

Rating

Contactless thickness measuring apparatus and measuring method f does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Contactless thickness measuring apparatus and measuring method f, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Contactless thickness measuring apparatus and measuring method f will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2400799