Wide-angle projection optical system

Abstract

The invention relates to a wide-angle projection optical system between an object side and an image side. The wide-angle projection optical system comprises a first optical system and a second optical system. The first optical system comprises a first lens unit and a second lens unit. The second optical system comprises a Mangin mirror. The first lens unit with positive effective optical power comprises an aperture diaphragm, provides the optical feature matching projection light rays of the object side and collects the light rays onto the aperture diaphragm. The second lens unit behind the first lens unit has the positive effective optical power. Relative to the first lens unit, the aperture diaphragm and the second lens unit, the Mangin mirror is closer to the image side. The first lens unit and the second lens unit form distortion real images at the front of the Mangin mirror which is provided with a penetration face and a reflection face, in this way, the light rays are subjected to the secondary refraction and the primary reflection, so that an image distortionless after zooming is generated on a screen and thinned, with aberration thereof reduced.

Description

technical field [0001] The invention relates to a projection optical system, in particular to a wide-angle or ultra-short-focus projection optical system. Background technique [0002] The wide-angle projection lens has a larger field of view or a shorter Effective Focal Length (EFL), so compared with a projection display device with a conventional projection lens, a projection display device with a wide-angle projection lens can be used at a shorter distance A video screen of a specific size is projected inside. [0003] At present, the integrated system of projection display equipment and interactive whiteboard has gradually become a useful tool in indoor places such as classrooms, lecture halls or meeting rooms to provide interactive functions such as education, display or entertainment. Figure 1A A schematic diagram showing the architecture of an integrated system of a traditional projection display device and an interactive whiteboard. like Figure 1A As shown, when t...

AI Technical Summary

Problems solved by technology

[0007] The main purpose of the present invention is to provide a short-focus wide-angle projection optical system to solve the risks of existing optical systems to the safety of users, as well as the problems of image aberration and image distortion.

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