Correlated modulation imaging (CMI)
US6630669B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 28, 2000 |
| Grant date | Oct 7, 2003 |
| Priority date | — |
| Expiry date | Mar 28, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C27/026
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
In the present invention of Correlated Modulation Imaging (CMI), the weak optical image signal (and therefore the signal current) is modulated, and the signal integration direction is correlated to the modulation. Therefore, the dark and/or background current, which are not modulated, are cancelled, while the signal current is integrated. As a result, the total integration time of the signal of each pixel is increased, and its signal to noise ratio and dynamic range are improved. Besides, the CMI noise spectrum peaks at the modulation frequency, and therefore, the detector's 1/f and other low frequency noises can be suppressed. In the present invention, the method and theory of CMI, as well as the means and steps for the realization of CMI, are explicitly developed. Two versions of CMOS devices (CMI unit pre-amplifier version 1 and 3), with their circuitry design and testing data are presented as the critical component for correlated modulation imaging. A prototype chip of the CMI circuitries has been fabricated by the MOSIS 0.5-micron foundry. SPICE circuitry simulation has demonstrated the functioning of CMI unit pre-amplifier version 1 and 3 as designed. Experimental work has de…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.