Rear projection screen and projection system

Abstract

The invention discloses a rear projection screen. The rear projection screen comprises a Fresnel lens layer, a cylindrical lens layer and a micro-lens layer which are sequentially arranged in the light-out direction of a projection lens. The micro-lens layer comprises a micro-lens set composed of first micro-lenses. The first micro-lenses are positive lenses, the focal distances are larger than those of cylindrical lenses of the cylindrical lens layer, and therefore all divergent primary light beams converge again through the long focal distances; due to the fact that convergence is achieved through the relatively long focal distances, the re-divergence degree generated after all the primary light beams converge is reduced compared with the divergence degree of light beams directly emitted from the cylindrical lens layer, the overlap ratio of all the primary light beams is increased, and the color cast problem generated when images are viewed at different visual angles of a projection screen is solved. The invention further discloses a projection system with the projection screen.

Description

technical field [0001] The invention relates to the field of display technology, in particular to a rear projection screen and a projection system. Background technique [0002] In the field of rear projection display, especially in the field of rear projection display, projection screens with Fresnel microlens structures are usually used, such as figure 1 As shown, along the light emitting direction of the projection lens, passing through the Fresnel lens structure layer 11 and the lenticular lens structure layer 12 in sequence, the focal length of the projector and the focal length of the rear projection screen are matched during use, and the picture can be displayed on the rear projection screen. The specific light path diagram is as figure 2 As shown, the Fresnel lens structure layer 11 converges and collimates the light incident on the screen, and the convex lens part in the lenticular lens structure layer 12 receives the collimated light and converges it. Theoretical...

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Problems solved by technology

[0003] However, in practical applications, according to the test results of the white field behind the rear projection screen, the technicians found that the color shift at the center of the screen, that is, the horizontal viewing angle is 0, and as the horizontal viewing angle increases, the resulting The color shift will also increase accordingly, and, as the vertical viewing angle increases, the resulting color shift will also increase, that is, as the viewing angle increases, different degrees of color shift will occur. The direct visual performance of the color shift is The white point is no longer the preset color temperature value, but it is displayed with a certain primary color color, so that when the human eye watches the display screen at different angles of view or different positions, there will be inconsistencies in the image color, especially for large-screen splicing displays. In scenes where white scenes are used more often, such as PPT presentations in large conference rooms, color casts from different viewing angles or different positions will greatly reduce the user experience

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