Projection lens

Abstract

The embodiment of the invention relates to the technical field of optics, and discloses a projection lens. The display module comprises a display chip, an equivalent plate lens, a first refraction lens group, a diaphragm and a second refraction lens group which are arranged in sequence, the first refraction lens group comprises a first refraction lens and a dual-bonded lens, wherein the dual-bonded lens comprises a second lens and a third lens, the total length of the projection lens is smaller than 32mm, the field angle is 65 degrees, the depth of field at the projection distance of 400 mm can reach + / -170 mm, the projection lens can stably output a clear image during close-range projection, and the use feeling of a user is good.

Description

technical field [0001] Embodiments of the present invention relate to the field of optical technologies, and in particular to a projection lens. Background technique [0002] Nowadays, with the rise of housing prices, home buyers usually can only choose smaller houses. It is inevitable that the width of the living room, bedroom and other rooms will also shrink. It is usually necessary to place or install an ordinary projector in the living room. Very inconvenient, and can not achieve better projection effect, therefore, the projector that can realize short-distance projection is more and more favored by consumers, only needs to place projector in front of the projection screen, can realize short-distance projection. [0003] In the process of implementing the embodiments of the present invention, the inventors have found that there are at least the following problems in the above related technologies: general projection lenses have a certain depth of field, but the projectio...

AI Technical Summary

Problems solved by technology

[0002] Nowadays, with the rise of housing prices, home buyers usually can only choose smaller houses. It is inevitable that the width of the living room, bedroom and other rooms will also shrink. It is usually necessary to place or install an ordinary projector in the living room. It is very inconvenient and cannot achieve a good projection effect. Therefore, projectors that can realize short-distance projection are more and more favored by consumers. You only need to place the projector in front of the projection screen to realize short-distance projection.

[0003] In the process of implementing the embodiments of the present invention, the inventors have found that there are at least the following problems in the above related technologies: general projection lenses have a certain depth of field, but the projection distance has a certain range. After the projection distance is shortened, the imaging quality of the lens is usually very low. It is easy to get worse, and the depth of field will become smaller and smaller. When using it at a close distance, it is usually impossible to move the projector slightly to produce a clear image, and the user experience is not good.

Images