Method and apparatus for independently calibrating light source and photosensor arrays
US5757425A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 19, 1995 |
| Grant date | May 26, 1998 |
| Priority date | — |
| Expiry date | Dec 19, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N25/673
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method of calibrating an image sensor having an array of pixel sensor sites, and an area light source having a corresponding array of pixel emission sites, comprising the steps of: PA1 a. measuring the output of the light source in a first region with a radiometer to generate an absolute measured light value; PA1 b. identifying a first region of the image sensor corresponding to the first region of the light source; PA1 c. successively positioning, reading out, and stepping the image sensor with respect to the light source to create a first file of pixel values representing one pixel in the first region of the sensor that has read every pixel in the first region of the source, and a second file of pixel values representing one pixel in the source that has been read by every pixel in the first region of the sensor; PA1 d. calibrating each pixel in the first region of the light source using the absolute measured light value and the pixel values in the first file; PA1 e. calibrating each pixel in the first region of the sensor using the calibrated value of one pixel in the first region of the light source and the pixel values in the second file; and PA1 f. repositioning the sensor w…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.