The picture quality of reversing camera monitors depends the standrard of the sensor. Most CMOS reversing cameras use a reasonable and inexpensive sensor.
CCD reversing cameras almost all tend to use much better quality sensors. They produce significantly better images with first-rate colour definition – which is seen much better in the dark. This means it produces a quality night-time black and white image.
The better the sensor the better the image. Sharp and Sony sensors for reversing cameras are known for producing a good quality images – with Sony having a slight edge.