Abstract
High dynamic range of the CMOS image sensor is important, especially applied to the security surveillance. While real
scenes produce a wide range of brightness variations, vision systems use low dynamic range image detectors that
typically provide poor quality images, which greatly limit what vision can acquire today. Due to the various environment
of surveillance, dynamic range of image sensor is more important than other conditions. This paper demonstrates a new
method for significantly improving the dynamic range. Compared to the other methods to enhance dynamic range like
multiple sampling or multiple exposure and so on, the approach which this paper puts forward ensures image quality, at
the same time, greatly improves the dynamic range of dark light conditions, and also easy to operate and accomplish.
The sensor is implemented in 0.18-μm CMOS technology and achieves 5mm×5mm chip size with 6μm×6μm pixels. The
results of the chip test are proposed in the paper. A scene with measured dynamic range exceeding 86dB but power is
only about 70mW, which is especially suitable for security surveillance application.
