Projecting apparatus

Abstract

A projecting apparatus comprises: a projecting lens, wherein the projecting lens comprises a first lens group with an imaging optical axis and a first effective refractive index and a second lens group with a second effective refractive index; and an image generating device with a light valve, wherein the second lens group is installed between the first lens group and light valve, the light valve transmits a projection light generated by the image generating device to the projecting lens, the projecting light generates an intermediate image through the second lens group, the intermediate image is focused on a projecting screen to generate an image through the first lens group, the centers of the image and the light valve are positioned at the same side of the imaging optical axis, and the center of the intermediate image is positioned at the other side of the imaging optical axis. The invention has the characteristic of ultra wide angle and the advantages of simple assembly, low manufacturing cost, etc.

Description

technical field [0001] The present invention relates to a projection device, and more particularly to a projection device with wide-angle characteristics. Background technique [0002] For larger projection spaces such as large conference rooms or lecture venues, it is usually necessary to match a larger projection screen. However, the size of the projection screen of the projection device is limited by the structural design of the projection lens. Therefore, wide-angle projection lenses have been applied in projection devices. However, traditionally, wide-angle projection lenses are mostly manufactured using the principle of one-time imaging. This technology usually results in too large front group lenses or the need to match other lenses such as reflective mirrors or lenses with special mirror surfaces, resulting in high production costs. And it is not easy to be accepted by the market. Contents of the invention [0003] The invention relates to a projection device, w...

AI Technical Summary

Problems solved by technology

However, traditionally, wide-angle projection lenses are mostly manufactured using the principle of one-time imaging. This technology usually results in too large front group lenses or the need to match other lenses such as reflective mirrors or lenses with special mirror surfaces, resulting in high production costs. and less acceptable to the market

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