viewing angle
The viewing angle of a LCD display is symmetrical on both sides, but not necessarily symmetrical on the top and bottom. For example, when the incident light from the backlight passes through a polarizing plate, liquid crystal, and orientation film, the output light has specific directional characteristics, which means that most of the light emitted from the screen has a vertical direction. If we look at a completely white image from a very oblique angle, we may see black or color distortion. Generally speaking, the up and down angles should be less than or equal to the left and right angles. If the viewing angle is 80 degrees left and right, it means that the screen image can be clearly seen at the position starting from the normal of the screen at 80 degrees. However, due to the different ranges of human vision, if one does not stand within the optimal viewing angle, there will be errors in the colors and brightness they see.
visible area
The size indicated on the LCD display is consistent with the actual usable screen range. For example, a 15.1-inch LCD display is approximately equivalent to the viewing range of a 17 inch CRT screen.
