Apparatus for and method of measuring boundary surface
US4767211A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 20, 1987 |
| Grant date | Aug 30, 1988 |
| Priority date | — |
| Expiry date | Aug 20, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B11/24
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus for and a method of measuring a boundary surface of a sample are disclosed in which a ratio of the light quantity of a part of reflected light from a sample which travels in the vicinity of the optical axis of the reflected light, to the light quantity of another part of the reflected light which is directed to a position deviating from the optical axis by a predetermined distance is used to accurately measure a boundary surface of a sample. Since the accuracy of measurement is increased by using the above ratio, light capable of passing through the sample can be used as incident light. Thus, a deep hole in the surface of the sample and a void such as an air bubble in a living being sample, which cannot be measured by the prior art, can be measured very accurately.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.