Contrast is the difference in the visual perception which in general is supposed to be between lighter and darker objects. The Contrast ratio in Plasma TV can be defined as the ratio of the degree of the part that is brightest to the degree of the darkest spot that can be produced by the television. This ratio is expressed as the number of shades of grey in between those spots. A higher contrast rate is a requisite of almost every appliance but it also needs to be capable of providing it. 5,000:1 which is considered a good ratio of contrast but when it is used on screens larger than 42 inches, the image may get blurred. Hence it becomes important to determine the perfect contrast ratio depending on the system requirements so that an optimum viewing experience is guaranteed every time. However this ratio between the brightest and darkest spots determines only the contrast ratio that is static by nature.

Different manufacturers have different methods of contrast ratio ratings and hence it is not advisable to compare the ratings of each other. But the most popular method that has been used to measure the contrast ratio is the CRT or the Cathode Ray Tube method. This method uses an ideal room which absorbs all the light and any light that comes would be from the Television. Hence the contrast ratio of the image would be that of the Television. The other methods to determine the contrast ratio are ‘full on full’ method, ANSI Contrast method and by using DLP Projectors.

There can be no relation to the claimed contrast ration by the company and the actual display the user receives. This is due to a number of incorrect and illegal ways resorted to by the manufacturers in measuring the contrast ratio. Sometimes they do not use the entire screen but use a small portion of it to get the bright light or even the usage of the screen without the protective panel so that the brightest spot can be manipulated. The darkest spots are also manipulated by turning off the display while taking the measurement. Hence the contrast ratio must be ensured from the above said methods acceptable methods.

Contrast ratio in Plasma TV is one of the most important deciding factors one needs to consider before buying it. As per marketing practice it is only the contrast ratio that has a dynamic capability is displayed and in many cases this is not directly comparable to the static contrast ratio. Plasma TV with a particular contrast ratio would show a better quality picture than an LCD with the same contrast ratio. The best way to determine the contrast ratios in these scenarios is to measure these capabilities of a TV in a totally dark room because in ordinary circumstances the reflected light from other surfaces will contribute to the light from the TV and makes it hard to measure the exact contrast ratio.