HDRC

HDRC ( English High Dynamic Range CMOS ) is a new technology in the field of CMOS image sensors . HDRC sensors are particularly powerful when used under extreme light conditions (overexposure and underexposure) as well as with strong backlight. In contrast to conventional CMOS sensors and CCD sensors , the output voltage of HDRC sensors is not a linear function of the light intensity, but a logarithmic function of the intensity. This behavior is similar to the sensitivity of the human eye ( Weber-Fechner law ).

In HDRC cameras, the light-sensitive element (a photodiode ) is combined with a CMOS field effect transistor for each image point ( pixel ) in order to obtain a signal proportional to the light intensity. Since the characteristic curve of the logarithmization fluctuates from pixel to pixel (offset voltage), a correction image of a uniformly bright area must be subtracted from the actual image. This process is similar to the white image correction in conventional image sensors, but due to the logarithmic relationship, the HDCR sensor subtracts instead of dividing.

HDRC sensors are, for example, very suitable for black and white surveillance cameras and for applications in road traffic (insensitive to glare from headlights).

Trademark

HDRC is registered as a European Community Trademark No. 000679118 Class 9 with the "Office for Harmonization in the Internal Market (trademarks, designs and models)". The brand owner is the Institute for Microelectronics in Stuttgart.

literature

Bernd Hoefflinger (Ed.): High-Dynamic-Range (HDR) Vision (= Springer Series in Advanced Microelectronics 26). Springer, Berlin 2007, ISBN 978-3-540-44432-9

Web links

Lecture on HDRC cameras at the University of Stuttgart (PDF file; 2.95 MB)