contrast ratio


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contrast ratio

[′kän‚trast ‚rā·shō]
(electronics)
The ratio of the maximum to the minimum luminance values in a television picture.

contrast ratio

The ratio of the reflectance of a dry paint film over a black substrate having 5 percent reflectance or less, to the reflectance of the same paint equivalently applied over a substrate having an 80 percent reflectance.

contrast ratio

The ratio of the brightest white to the darkest black on a TV or computer monitor. The larger the number, the greater the extremes; for example, car headlights can appear brilliant next to the pitch black of the night sky. Contrast ratio is an important criterion in screen quality.

White Divided by Black
The ratio is derived by the brightest luminance divided by the darkest luminance in candelas per square meter (cd/m2). For example, if white is 98 cd/m2 and black is 0.02, the ratio is 4900:1. In the 2013-2014 time frame, and using the same testing method, LED TVs have been measured with contrast ratios from 700:1 to 7500:1.

Following are two of many measurement methods; however, contrast ratios are known to be "invented" because vendors can apply a technique in different ways to come up with higher numbers. One bogus approach is to adjust the TV white level to settings the viewer would never really use.

ANSI Contrast and Full On/Off
ANSI Contrast uses a checkerboard of alternating black and white squares, and the average white output is divided by the average black output. The test may be done by calibrating the white to 100 cd/m2 and then measuring the black.

Full On/Off measures an all-white screen with an all-black screen and always produces a higher ratio than the ANSI Contrast. See LED TV, Dolby HDR and dynamic contrast.
References in periodicals archive ?
The 77", 65" and 55" models all feature an Infinite Contrast ratio, 4K ULTRA HD (resolution of 3840 x 2160 pixels), TruA[degrees]4K Engine Pro, webOS, 4K 3D+ ULTRA HD and a HEVC Decoder.
The new reflective liquid crystal chip provides contrast ratios of 100,000:1 or higher(1) and has the ability to reproduce bright, natural-looking images and deliver rich gradations.
The C2 Fine technology that enabled high contrast ratios in transmissive HTPS panels has been optimized for the reflective HTPS panels, and Epson's unique planarization technology is used to make the reflective layer almost perfectly flat so as to control the scattering of light.
7-inch full HD D-ILA devices and wire grid optical engine to enable it to further improve contrast to twice the ratio of the best conventional projectors and attain a native contrast ratio of 30,000:1 for super-smooth images exhibiting deep, true black level without a trace of gray.
But the highest contrast ratio so far in an LCD monitor is that of Sharp's existing model at 1,500 to 1, it said.
Featuring sophisticated design, a fully integrated ATSC tuner for high definition reception and built-in SD and CableCARD slot, the VIERA line features contrast ratios from 3000:1 to 4000:1 for brilliant, razor-sharp pictures.
The displays feature a 25ms response rate, and 300:1 contrast ratio.
DLP-based products are known for their native contrast ratio levels which ultimately sets minimum product contrast ratio level for all scene content.
Tokyo, Japan, Aug 25, 2006 - (JCN) - Mitsubishi Electric Corporation introduced the LVP-HC3100 home theater projector with a state-of-the-art DMD chip and cutting-edge engine enabling the contrast ratio of 4500:1 on August 22 in Japan.
1-Inch (31cm Diagonal) TFT LCD - Supports super video graphics array (SVGA) resolution - Achieves high visibility High brightness of 400cd/m2 and high contrast ratio of 600:1 Wide viewing angle of 160 degrees horizontally and 140 degrees vertically (contrast ratio greater than 10:1) Fast response time of 25ms.
Weighing just 3 pounds, the U4-237 features 2000 Lumens and a 2000:1 contrast ratio and a CompactFlash card wireless LAN module that can connect to multiple PCs.
The CMP5000WXU features XGA resolution and a sharp 900:1 contrast ratio for exceptional image quality.