FLIR imager with hybrid optical/electronic processor
US4672439A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 4, 1985 |
| Grant date | Jun 9, 1987 |
| Priority date | — |
| Expiry date | Sep 4, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N23/23
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A FLIR imager is modified to include a hybrid optical/electronic processor for automatic local area dynamic range normalization. FLIR imagers have an objective lens for focusing IR energy emanating from a scene on a detector array. The detector array generates electrical signals representative of the scene. LEDs generate a visible picture of the thermal image of the scene for a video processor for formatting the signals for a particular type display (TV). The hybrid optical/electronic processor is inserted between the LEDs and the video processor; it includes a beamsplitter for directing the image to a pair of CCD cameras. The image at one camera is set in sharp focus to preserve all of the spatial frequency content (allpass) through the image reconstruction optics. While the image at the second camera is slightly defocused for averaging image information over small local regions the size of the defocused point spread function (spatial lowpass filtered). The electrical signal outputs of the CCD cameras are connected to a differential amplifier for subtracting the lowpass image from the allpass image to produce the highpass image and amplification to bring the resulting signal level…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.