CN218122345U

CN218122345U - Miniature projection lens

Info

Publication number: CN218122345U
Application number: CN202221354583.4U
Authority: CN
Inventors: 薛政云; 许熠宸; 罗杰; 林文斌; 胡青平
Original assignee: Fujian Forecam Tiantong Optics Co Ltd
Current assignee: Fujian Forecam Tiantong Optics Co Ltd
Priority date: 2022-06-01
Filing date: 2022-06-01
Publication date: 2022-12-23
Anticipated expiration: 2032-06-01

Abstract

The utility model relates to a micro projection lens, which comprises a first lens, a second lens, a third lens, a diaphragm and a fourth lens which are arranged along the incident light path of light from left to right in sequence; the first lens is a positive meniscus lens, the second lens is a positive meniscus lens, the third lens is a double-concave negative lens, and the fourth lens is a double-convex positive lens; all lenses are made of glass material. The structure is simple and reasonable, the assembly is easy, the tolerance sensitivity is low, and the method is more suitable for large-scale high-yield production; the F number is smaller, the clear aperture is larger, and higher system light throughput and image surface brightness are ensured; the optical structure stability is ensured by adopting the full-glass structure design; the large-angle oblique projection of more than or equal to 45 degrees can be realized by matching with the film adjustment, and the image quality of different positions of a projection picture is ensured.

Description

Miniature projection lens

Technical Field

The utility model relates to a miniature projection lens.

Background

In recent years, optical means for decoration, promotion and marketing have become a trend, wherein related products such as advertisement projection lamps, welcome lamps and the like have even become the standard in the industry. However, most similar products on the market still use the traditional imaging method, and the imaging picture is often severely deformed when the projection is tilted, and the imaging quality at different positions is far away.

SUMMERY OF THE UTILITY MODEL

In view of the deficiencies of the prior art, the technical problem to be solved of the present invention is to provide a micro projection lens.

In order to solve the technical problem, the technical scheme of the utility model is that: a micro projection lens comprises a first lens, a second lens, a third lens, a diaphragm and a fourth lens which are sequentially arranged from left to right along a light incident light path; the first lens is a positive meniscus lens, the second lens is a positive meniscus lens, the third lens is a double-concave negative lens, and the fourth lens is a double-convex positive lens; all lenses are made of glass material.

Preferably, the focal length of the optical system is set to f, and the focal lengths of the first lens, the second lens, the third lens and the fourth lens are set to f ₁ 、f ₂ 、f ₃ 、f ₄ Wherein f is ₁ 、f ₂ 、f ₃ 、f ₄ And f satisfy the following ratio: 0.5<f ₁ /f<2.5，0.8<f ₂ /f<1.8，-1.5<f ₃ /f<-0.1，0.1<f ₄ /f<1.5。

Preferably, the first lens satisfies the relation: n is a radical of _d ≥1.5，V _d Not less than 50.0; the second lens satisfies the relation: n is a radical of _d ≥1.5，V _d Less than or equal to 50.0; the third lens satisfies the relation: n is a radical of _d ≥1.5，V _d Less than or equal to 50.0; the fourth lens satisfies the relation: n is a radical of _d ≥1.5，V _d Less than or equal to 50.0; wherein N is _d Is refractive index, V _d Abbe constant.

Preferably, the total optical length TTL of the optical system and the focal length f of the optical system satisfy: TTL/f is less than or equal to 3.1.

Preferably, the F-number of the optical system is less than or equal to 2.0.

Compared with the prior art, the utility model discloses following beneficial effect has: the structure is simple and reasonable, the assembly is easy, the tolerance sensitivity is low, and the method is more suitable for large-scale high-yield production; the F number is smaller, the clear aperture is larger, and higher system light throughput and image surface brightness are ensured; the optical structure stability is ensured by adopting the full-glass structure design; the large-angle oblique projection of more than or equal to 45 degrees can be realized by matching with the film adjustment, and the image quality of different positions of a projection picture is ensured.

The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.

Drawings

Fig. 1 is a diagram of an optical system according to an embodiment of the present invention;

fig. 2 is a schematic diagram of an oblique projection according to an embodiment of the present invention;

fig. 3 is a full operating band axial chromatic aberration diagram of an embodiment of the present invention;

FIG. 4 is a full operating band vertical axis color difference diagram of an embodiment of the present invention;

FIG. 5 is a full operating band field curvature distortion diagram of an embodiment of the present invention;

fig. 6 is a schematic diagram illustrating the deformation of a film sheet according to an embodiment of the present invention;

fig. 7 is a schematic diagram of a projection effect according to an embodiment of the present invention;

in the figure: l1-a first lens; l2-a second lens; l3-a third lens; STO-stop; l4-fourth lens; IMA-imaging plane.

Detailed Description

The present invention will be further explained with reference to the drawings and the embodiments.

It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the disclosure herein. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an", and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

As shown in fig. 1 to 7, the present embodiment provides a micro projection lens, which includes a first lens, a second lens, a third lens, a diaphragm, and a fourth lens sequentially arranged along a light incident path from left to right; the first lens is a meniscus positive lens, the second lens is a meniscus positive lens, the third lens is a biconcave negative lens, and the fourth lens is a biconvex positive lens; all lenses are made of glass material.

In an embodiment of the present invention, the focal length of the optical system is set to be f, and the focal lengths of the first lens, the second lens, the third lens and the fourth lens are respectively f ₁ 、f ₂ 、f ₃ 、f ₄ Wherein f is ₁ 、f ₂ 、f ₃ 、f ₄ And f satisfy the following ratio: 0.5<f ₁ /f<2.5，0.8<f ₂ /f<1.8，-1.5<f ₃ /f<-0.1，0.1<f ₄ /f<1.5。

In an embodiment of the present invention, the first lens satisfies the following relation: n is a radical of hydrogen _d ≥1.5，V _d Not less than 50.0; the second lens satisfies the relation: n is a radical of hydrogen _d ≥1.5，V _d Less than or equal to 50.0; the third lens satisfies the relation: n is a radical of hydrogen _d ≥1.5，V _d Less than or equal to 50.0; the fourth lens satisfies the relation: n is a radical of hydrogen _d ≥1.5，V _d Less than or equal to 50.0; wherein N is _d Is a refractive index, V _d Abbe constant.

In an embodiment of the present invention, the total optical length TTL of the optical system and the focal length f of the optical system satisfy: TTL/f is less than or equal to 3.1.

In the embodiment of the present invention, the F number of the optical system is less than or equal to 2.0.

In the embodiment of the present invention, the technical indexes of the optical system of this embodiment are as follows:

(1) Focal length: EFFL is more than or equal to 20.0 and less than or equal to 25.0mm; (2) the aperture F is less than or equal to 2.0; and (3) the projection distance is more than or equal to 145mm and less than or equal to 155mm.

In order to realize the above design parameters, the specific design adopted by the optical system of this embodiment is as follows:

the optical system of the embodiment realizes the design of large aperture, small size and low temperature floating, and can realize the correction of large-angle inclined projection trapezoidal distortion after the film is subjected to customized deformation.

While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention. However, any simple modification, equivalent change and modification made to the above embodiments according to the technical substance of the present invention still belong to the protection scope of the technical solution of the present invention.

Claims

1. A miniature projection lens which characterized in that: the device comprises a first lens, a second lens, a third lens, a diaphragm and a fourth lens which are sequentially arranged from left to right along a light incident light path; the first lens is a positive meniscus lens, the second lens is a positive meniscus lens, the third lens is a double-concave negative lens, and the fourth lens is a double-convex positive lens; all lenses are made of glass material.

2. The micro projection lens of claim 1, wherein: setting the focal length of the optical system as f, and the focal lengths of the first lens, the second lens, the third lens and the fourth lens as f ₁ 、f ₂ 、f ₃ 、f ₄ Wherein f is ₁ 、f ₂ 、f ₃ 、f ₄ And f satisfy the following ratio: 0.5<f ₁ /f<2.5，0.8<f ₂ /f<1.8，-1.5<f ₃ /f<-0.1，0.1<f ₄ /f<1.5。

3. The micro projection lens of claim 1, wherein: the first lens satisfies the relation: n is a radical of _d ≥1.5，V _d Not less than 50.0; the second lens satisfies the relation: n is a radical of _d ≥1.5，V _d Less than or equal to 50.0; the third lens satisfies the relation: n is a radical of hydrogen _d ≥1.5，V _d Less than or equal to 50.0; the fourth lens satisfies the relation: n is a radical of hydrogen _d ≥1.5，V _d Less than or equal to 50.0; wherein N is _d Is refractive index, V _d Abbe constant.

4. The miniature projection lens of claim 1, further comprising: the total optical length TTL of the optical system and the focal length f of the optical system meet the following conditions: TTL/f is less than or equal to 3.1.

5. The miniature projection lens of claim 1, further comprising: the F number of the optical system is less than or equal to 2.0.