Universal short focus projection optical system

An optical system and short-focus projection technology, applied in the optical field, can solve problems such as low matching, high cost, and complex structure, and achieve the effects of reducing production costs, ensuring quality, and reducing costs

CN107065406AInactive Publication Date: 2017-08-18北京和光科技有限公司
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Patent Information

Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Publication Date
2017-08-18
Estimated Expiration
Not applicable · inactive patent

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Abstract

The invention discloses a universal short focus projection optical system. The system includes optical lenses, a diaphragm and an optical prism. The system is provided with a first lens unit having negative focal power, a second lens unit having positive focal power, a third lens unit having negative focal power, the diaphragm, a fourth lens unit having positive focal power and the optical prism arranged successively. The first lens unit includes an aspheric surface resin element. The fourth lens unit contains low dispersion glass material. The focal length of the universal short focus projection optical system is f and the focal length of the first lens unit is f1, wherein -0.15<f / f1<-0.6. The rear focal length of the universal short focus projection optical system is BFL, wherein 13<BFL<17. The maximal diameter of the universal short focus projection optical system is D, wherein D<60mm. According to the invention, universal design of the projection system in a DLP projector or a LCD projector is achieved. At the same time, the production cost is reduced further.
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Description

technical field

[0001] The invention relates to the field of optical technology, in particular to a general-purpose short-focus projection system. Background technique

[0002] Projectors are widely used in education, business, engineering, household and other places. In the field of engineering, the complex and limited installation environment often requires the projector to be equipped with a short-focus lens to achieve a greater picture effect within a short distance. Most of the imported short-focus optional lenses are expensive and have a long cycle, which cannot meet the needs of domestic projects. Domestic lenses have gradually become the first choice for multimedia projects in cultural venues. High-quality imaging has always been the disadvantage of domestic lenses. Domestic substitute lenses are often considered costly and cannot be designed to the extreme, sacrificing some imaging quality. For the two types of DLP and LCD commonly used in engineering, due to the ...

Examples

Embodiment Construction

[0015] In order to solve the shortcomings of the existing domestic lenses and different types of projectors, such as low compatibility, large aperture, too long overall length, and low consistency, the present invention provides a general-purpose short-focus projection optical system. The present invention will be described in further detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

[0016] Such as figure 1 As shown, the embodiment of the present invention relates to a general-purpose short-focus projection optical system (hereinafter referred to as the optical system), including: a first lens group G1 with negative refractive power, a second lens group G2 with positive refractive power, a negative light The third lens group G3 of focal power, the stop S1, the fourth lens group G4 of positive refra...