What is monitor contrast?

Somehow imperceptibly the time came when monitors based on CRTs completely disappeared from the shelves of computer equipment stores, giving way to their liquid crystal counterparts. The unfamiliar with this technology people are often confused in terms, as there are several names of the same thing at once. In order to avoid misunderstanding, let's clear this question right away: LCD, LCD - all this is the same liquid crystal technology, not different. LCD means Liquid Crystal Display. Indirectly, the term "TFT" can be attributed here, meaning the use of thin-film transistors for matrix control. Since they are not used in CRTs, it is obvious that the mention of TFT points to the LCD.

Having replaced the old CRT monitors with modern LCDs, many owners have faced an amazing phenomenon - during the first time after the transition the eyes begin to hurt, and some even redden the face. Hence the following question - "how to adjust the monitor for the eyes." The Web provides many recommendations, but most of them are incomplete, because the very reason for what is happening is cleverly overlooked. Indeed, if the contrast of the monitor and the brightness in LCD and CRT technologies are similar concepts, then where is the discomfort in the eyes when working with the LCD? After all, this should not be. The real reason for eye fatigue is that LCD monitors flicker. The principle of operation of the fluorescent backlight is based on gas discharges in the tube, and even modern LED-backlights also have a flicker (read about PWM LED control). In addition, the color of the glow, both the lamp and the diodes - is unnatural, it has a defective spectrum. "By eye" is invisible, but the visual receptors can not be fooled.

In general, the contrast of the monitor is a numerical value representing the ratio of the brightness differences of the lightest white point to the darkest black point. In the passport data of monitors is indicated in the form of "xxx: y". In fact, this is another way of recording. For example, the contrast of the monitor with a maximum brightness of 300 cd / m2 and a minimum of 0.5 cd / m2 is (300-0.5) /0.5 = 599: 1. It is generally accepted that the higher the contrast value, the clearer the picture. This is partly true, but only to a certain extent, since an infinite increase leads to image distortions (bright details on a white background are no longer distinguishable). If the contrast of the monitor is not set up properly, this is one of the reasons for the sensation of sand in the eyes when changing CRTs on LCD.

Note that all methods of setting parameters proposed in the Network are subjective. Each user must perform an adjustment based on personal preferences only. In the Windows 7 operating system, there is a built-in brightness adjustment of the monitor, which allows you to optimally set the brightness, as well as contrast and gamma.

On the desktop, click the right mouse button, follow the "Screen Resolution", then "Make text and other elements more or less" and "Color Calibration". Clicking "Next", follow the advice of the wizard (here there is detailed help). At the end, you will be asked to configure the display of fonts using Clear Type technology: in the samples, we indicate the most clear and "fatty" lines of letters.

Additionally, you can configure the monitor itself. To do this, we set the contrast by 20-40%, and we achieve brightness with a high-quality image. In some cases, the brightness can be zero, which is quite acceptable. The color temperature (deviation in the yellow or blue spectrum) should be set based on personal preferences. More natural is the yellow shade, corresponding to the color temperature of sunlight (6300 K). Different mechanisms for improving the image and dynamic contrast do not allow you to properly adjust the monitor, so you need to compare the improved and natural modes of operation and choose the best for yourself.