When capturing a dark scene with a high bright object, the monitoring camera will be saturated in some regions and the
details will be lost in and near these saturated regions because of the glare vision. This work aims at developing a
real-time night monitoring system. The system can decrease the influence of the glare vision and gain more details from
the ordinary camera when exposing a high-contrast scene like a car with its headlight on during night. The system is
made up of spatial light modulator (The liquid crystal on silicon: LCoS), image sensor (CCD), imaging lens and DSP.
LCoS, a reflective liquid crystal, can modular the intensity of reflective light at every pixel as a digital device. Through
modulation function of LCoS, CCD is exposed with sub-region. With the control of DSP, the light intensity is decreased
to minimum in the glare regions, and the light intensity is negative feedback modulated based on PID theory in other
regions. So that more details of the object will be imaging on CCD and the glare protection of monitoring system is
achieved. In experiments, the feedback is controlled by the embedded system based on TI DM642. Experiments shows:
this feedback modulation method not only reduces the glare vision to improve image quality, but also enhances the
dynamic range of image. The high-quality and high dynamic range image is real-time captured at 30hz. The modulation
depth of LCoS determines how strong the glare can be removed.