Electromagnetic wave detector using quantum wells and subtractive detectors
US6534758B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 10, 2001 |
| Grant date | Mar 18, 2003 |
| Priority date | — |
| Expiry date | Sep 18, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10F39/1847
Abstract
The basic idea is as follows: operational simulations of subtractive focal planes, based on the French patent No. 2 756 666, have shown that the optimal subtraction rate should not be total in order to preserve the dynamic range of the system. In this case, the low-frequency fluctuations of the temperature of the focal plane of the bias voltages will be amplified and will give rise to a fluctuation of the mean gray level of the signal at output of the multiplexer. This variation can be corrected simply by:the making of several columns of subtractive pixels without diffraction grating, for which the integrated signal is directly the residual level of the thermal current;the integration of a comparator circuit at input of the electronic card to subtract the signal generated in the reference pixels from the signals integrated into the active pixels.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.