What is the brightness measurement principle of LCD screen?
The luminance meter mainly uses a pair of light holes at a certain distance to receive the luminous flux with a fixed three-dimensional angle and a fixed projection area. as long as the surface area of the object is large enough, this value will not change with the distance of the object. In order to aim at the tested object, the imaging system is often used.
After passing through the objective lens, the measured light source is imaged on the porous (front optical aperture) mirror, some of which are received by the human eye through the mirror and eyepiece to aim and monitor the coincidence of the clear imaging surface and the porous mirror; the other part of the light reaches the V (λ) receiver through the small hole and backlight hole in the mirror. Luminance values are displayed with pointers or numeric headers.