The main performance indicators and parameters of LCD
1. Resolution: The resolution of the LCD is different from that of the CRT monitor, and generally cannot be adjusted arbitrarily. It is set and specified by the manufacturer. Resolution refers to how many pixels are in each row and how many pixels are in each column on the screen. It is generally expressed by a matrix determinant, where each pixel can be accessed individually by the computer. Now the resolution of LCD is generally SVGA display mode of 800 dots × 600 lines and XGA display mode of 1024 dots × 768 lines.
2. Refresh rate: The LCD refresh rate refers to the display frame rate, that is, the time for each pixel to refresh at this frequency, which is related to the screen scanning speed and the ability to avoid screen flicker. In other words, the refresh rate is too low, and the screen image may flicker or flicker.
3. Response time: The smaller the response time, the better. It reflects the speed at which each pixel of the liquid crystal display reacts to the input signal, that is, the speed at which pixels change from dark to bright or from bright to dark. The smaller the response time, the user will not feel the tail drag when watching the motion picture. Generally, the reaction rate will be divided into two parts: Rising and Falling; and the sum of the two shall prevail.
4. Viewing angle Generally speaking, the viewing angle of LCD is symmetrical, but it is not necessarily up and down. Moreover, the vertical angle is often smaller than the horizontal angle. Of course, the bigger the perspective, the better. However, everyone must understand the definition of perspective. When we say that the angle of view is 80 degrees to the left and right, it means that the screen image can still be clearly seen when standing at a position starting at 80 degrees from the normal of the screen, but each person's vision is different; therefore, we are subject to the contrast. The greater the contrast measured at the maximum viewing angle, the better.
5. Contrast
Contrast refers to the ratio between the brightest white area of ​​an image and the next darkest black area. In CRT monitors, the influence of contrast on its signal energy does not attract people's attention. In the LCD, contrast is one of the main parameters to measure its quality.
In a liquid crystal display, the higher the contrast, the richer the color gradation that the display can present. In the current general LCD display, the contrast ratio can reach 250: 1, and very few high-end products can reach 400: 1.
6. Brightness
Also in CRT displays, brightness is not a very important parameter to measure its performance. In the LCD display, it has become one of the main parameters to measure the quality of the LCD display together with the contrast.
On LCD monitors, the higher the brightness, the brighter and clearer the picture. The unit of brightness is cd / m2
It means the brightness of candlelight per square meter. At present, the brightness of the liquid crystal display can generally reach 200cd / m2, and good can reach 250cd / m2. The influence of brightness and contrast on the LCD display is interrelated, and the selection should be considered as balanced as possible.
7. Signal response time
The length of the signal response time determines whether the picture can be smooth. Example: Whether there is serious "ghosting" or "smearing" when playing 3D games or watching DVDs. The signal reaction time is usually the average signal reaction time and the rising signal reaction time. Example: 50ms / 25ms, of which 50ms is the average signal response time and 25ms is the rising signal response time. The average signal reaction time includes the rising signal reaction time and the falling signal reaction time, which is the overall signal reaction time. The rising signal reaction time is only part of the reaction time, which refers to the signal rising edge time. Therefore, the average signal response time should be used as a reference value.
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