Production of images using an array of light emitting diodes
US5051762A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 12, 1990 |
| Grant date | Sep 24, 1991 |
| Priority date | — |
| Expiry date | Oct 12, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/4015
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Apparatus and imaging method in which an LED exposure apparatus having an array of light emitting diodes stationed in a light exposing relationship to a photosensitive material to be imaged is calibrated to take into account the wavelength difference between light emitting diode emissions and the spectral sensitivity of the photosensitive medium. The exposure apparatus is calibrated by making separate energy measurements of each light emitting diode with a detector through a colored filter. The spectral response of the detector and filter combination matches that of the photosensitive material in the wavelength region of the emission of the light emitting diode. The energy measurement are used to modulate each exposure level of the array of light emitting diodes. The calibration method is used during exposure of the photosensitive material by the array of light emitting diodes, particularly for grey scale imaging. The detector and filter are used to modulate exposure in response to the energy measurements.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.