Straight-line optical path x-ray scanner which automatically adjusts scanning aperture size
US5218463A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 26, 1990 |
| Grant date | Jun 8, 1993 |
| Priority date | — |
| Expiry date | Nov 26, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N2201/0412
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A simple, low cost x-ray scanner providing enhanced resolution is formed by providing a straight-line optical path from an illuminating source, through the x-ray image to be scanned and thence to an imaging lens which forms an image on a CCD array. The x-ray film is fed by means of gravity to a pair of rollers, immediately above which are formed first and second apertures on either side of the roller. The film is eliminated through the apertures which provide a field stop for the optical system. A shutter immediately adjacent one of the apertures is coupled to a width-adjustment mechanism actuated by a feed guide for the film to thereby adjust the width of the aperture to the width of the film. The output of the CCD is modified to expand the output at low levels and compress it at high levels via a logarithmic mapping to adapt the high resolution CCD output to a lower resolution video display processor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.