Luminance correction system used in a vision system

A projection system with luminance control device, comprising:

• a video signal decoder, used to receive a video signal, and decode the video signal into three components of red, green, and blue (RGB);
• a photodetector, used to detect an environment luminance, and accordingly export a reference signal;
• and
• a correction circuit, used to receive the reference signal of the photodetector, and receive the three components of RGB, wherein the correction circuit also store a vision response curve at dark condition and a vision response curve at bright condition, so that a correcting vision response curve is determined according to the reference signal, and the correction circuit individually and relatively corrects luminance of the three components of RGB and exports the three components of RGB.

A method for adjusting an image luminance, comprising:

• providing a video signal, having three components of red, green, and blue (RGB);
• detecting an environment luminance, thereby to provide a reference signal;
• providing a vision response curve at dark condition and a vision response curve at bright condition;
• determining a correcting vision response curve, according to the reference signal, the vision response curve at dark condition, and the vision response curve at bright condition;
• and
• individually correcting the three components of RGB, using properties of the correcting vision response curve.