Photo electric feedback compensation controlled apparatus
US5514864A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 25, 1994 |
| Grant date | May 7, 1996 |
| Priority date | — |
| Expiry date | Mar 25, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J1/32
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus for photo-electric automatic feedback compensation control is used with a charged coupled device (CCD) scanner to efficiently bring the CCD scanner into optimal operating range by controlling the output intensity of a light source based upon output readings from the CCD. A voltage controlled power supply drives a light source to emit light through an optical system to irradiate a CCD scanner. The voltage induced in the CCD scanner is output and manipulated to produce a digital control signal. When the photo-electric conversion rate of the CCD is too high, the light emitting intensity of the light source is reduced based upon the output of the CCD. When the photo-electric conversion rate of the CCD is too low, the output intensity of the light source is increased based upon the output signal of the CCD scanner. Thus, the signal-to-noise (S/N) ratio can be increased without necessity of manual adjustment, and the different problems generated by differences in apparatus characteristics or different environments and timing can be easily overcome.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.