Film thickness inspection method and apparatus
US5773173A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 17, 1996 |
| Grant date | Jun 30, 1998 |
| Priority date | — |
| Expiry date | Jun 17, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N17/02
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A color filter thickness uniformity is evaluated quantitatively and accurately at high sensitivity by using a wavelength deviating by a predetermined wavelength from a central wavelength. The whole output of a screen is unified into one color tone by a monochromatic mask set between a white light source and a color filter to mask picture elements other than those with a specific color tone. The light emitted from the screen is filtered by a filter having a wavelength .lambda..sub.1 deviating by a predetermined wavelength .DELTA..lambda. from the central wavelength .lambda..sub.0 of the one color tone as the central wavelength, and the intensity of the filtered light is detected for each position on the screen to evaluate the intensity of the light detected for each position on the screen by a method such as image processing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.