What is Contrast Ratio (CR)?
Contrast ratio (CR) is the ratio of luminance between the brightest “white” and the darkest “black” that can be produced on a display. CR is another influence of perceived picture quality. If a picture has high CR, you will consider it to be sharper and crisper than a picture with lower CR. For example, a typical newspaper picture has a CR of about 5 to 7, whereas a high quality magazine picture has a CR that is greater than 15. Therefore, the magazine picture will look better even if the resolution is the same as that of the newspaper picture. A typical AMLCD exhibits a CR of approximately 300 to 700 when measured in a dark room. The CR on the same unit measured under ambient illumination is drastically lowered due to surface reflection (glare). For example, a standard 200 nit LCD measured in a dark room has a 300 CR, but will have less than a 2.0 CR under intense direct sunlight. This is due to the fact that surface glare increases the luminance by over 200 nits both on the “white” a