Traditional Culture Encyclopedia - Traditional stories - Why do you use a rough screen instead of a mirror to show movies?

Why do you use a rough screen instead of a mirror to show movies?

Because the rough curtain will diffuse reflection, you can see the movie clearly around the cinema, and the mirror will reflect light, which will affect people's sight, so it is not suitable.

Related introduction:

The curtain dedicated to projection is called projection screen, which is one of the most commonly used products in projector peripherals. If the projection screen is properly matched with the projector, high-quality projection effect can be obtained. Generally speaking, projection screens can be divided into reflective and transmissive types.

When light is incident on the surface of a transparent or translucent material, part of it is reflected, part of it is absorbed and part of it can be transmitted. Transmission is the emergent phenomenon of incident light after refraction through an object. The transmitted objects are transparent body or translucent bodies, such as glass and color filters.

Extended data

The screen has several influences on the movie appreciation experience. The most important one is the quality of the movie picture: brightness, color reproduction and contrast, which can distract attention through potential defects in the screen. The screen will also affect the acoustic performance of the speaker system behind the screen, especially the high frequency loss. The ideal brightness level of the screen is determined by referring to the SMPTE standard recognized all over the world.

The screen is the main factor of the brightness of the light reflected back to the audience. White plastic curtains scatter light and reflect most of the light to the ceiling and side walls, so they are lost. The screen called "gain" returns more light directly to the audience.

The gain level of the screen is related to the amount of reflected light, and its measurement is carried out according to the reference standard. The reflectivity of commercial white plastic curtains varies, but it is usually 0.8- 1.0 according to the reference standard.

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