Why is the projector screen wide and narrow?

The position of the projector should be at right angles to the projection screen as far as possible to ensure the projection effect. If they are not vertical, the picture will be trapezoidal. In this case, the user needs to use the "Trapezoidal Correction Function" to correct the trapezium to ensure that the picture is a standard rectangle.

Two methods:

1. Optical keystone correction and digital keystone correction. Optical keystone correction refers to adjusting the keystone by adjusting the physical position of the lens.

2. Digital keystone correction is realized by software.

Extended data

The light sources used by projectors include traditional high-intensity gas discharge light sources (such as ultra-high pressure mercury lamps, short-arc xenon lamps and metal halogen lamps) and new light sources represented by LED light sources and laser light sources. After the traditional light source projector is used for a period of time, it usually turns dark and yellow with the attenuation of light emitted by the light source. In the use of high-quality occasions, even if the light bulb is still glowing, it should be replaced.

Therefore, light attenuation has become an insurmountable obstacle for projectors using traditional light sources. With the development of semiconductor lighting technology and laser technology, LED light sources and laser light sources have developed rapidly not only in the lighting field, but also in the display field.

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