CN116794811A

CN116794811A - Compatible multisize LCD display screen camera lens

Info

Publication number: CN116794811A
Application number: CN202310050047.8A
Authority: CN
Inventors: 黄孝成; 宋春发
Original assignee: Sichuan Puju Photoelectric Technology Co ltd
Current assignee: Sichuan Puju Photoelectric Technology Co ltd
Priority date: 2023-02-01
Filing date: 2023-02-01
Publication date: 2023-09-22

Abstract

The invention discloses a multi-piece large-size LCD projection lens, which comprises a Fresnel lens, a first lens, a second lens, a double-cemented lens, a diaphragm, a third lens and a fourth lens which are sequentially arranged from an LCD end to a screen end; the fourth lens is a positive meniscus lens, the third lens is an 8-order aspheric lens, the second lens is a biconvex lens, and the first lens is an 8-order aspheric negative lens; the invention increases the brightness of the LCD projector by increasing the size of the light source window, increasing the clear aperture of the lens, reducing the relative aperture of the lens, plating an antireflection film on the surface of the lens, and the like; the resolution of the LCD is improved by increasing the number of projection lens optics, adding aspherical optics, using a cemented lens, etc.

Description

Compatible multisize LCD display screen camera lens

Technical Field

The invention relates to the field of LCD projection lenses, in particular to a lens compatible with a multi-size LCD display screen.

Background

The projection display technology is a display mode in which an image generated by a display device is projected onto a screen through an optical system to generate an image. The high-performance projection display technology is mainly characterized by large screen, high output brightness, high image resolution and the like. Early projection systems were bulky, heavy, costly, and limited in application. In recent years, with the development of display devices, light sources, and various optical systems, the volume and weight of projection apparatuses have been greatly reduced, the cost has been continuously reduced, and the application fields have been rapidly expanding. Currently in the projector industry, DLP projectors have high resolution and laser projectors have high brightness. These two projectors belong to the high-end model. But these two models are expensive and rarely purchased by the average household. The LCD projector has low price and high popularity and is popular with ordinary families. LCD projectors are currently no more than DLP and laser projectors in terms of resolution and brightness. In order to improve the resolution and brightness of the LCD projector, the invention provides a solution of a 6-piece type 5.2-inch LCD projection lens.

Disclosure of Invention

In order to solve the technical problems, the technical scheme provided by the invention is as follows:

a lens compatible with a multi-size LCD display screen comprises a Fresnel lens, a first lens, a second lens, a double-cemented lens, a diaphragm, a third lens and a fourth lens which are sequentially arranged from an LCD end to a screen end; the fourth lens is a positive meniscus lens, the third lens is an 8-order aspheric lens, the second lens is a biconvex lens, and the first lens is an 8-order aspheric negative lens.

Preferably, the thickness of the fourth mirror is less than 16mm and the focal length is greater than 130mm.

Preferably, the thickness of the center of the third lens is less than 9mm, and the focal length is less than-320 mm; the third lens and the double-cemented lens are arranged at intervals, the optical interval is larger than 22mm, and the diameter of the diaphragm is 46.3mm.

Preferably, the biconvex lens is a biconcave lens and a biconvex lens, the biconvex lens is arranged on one side of the biconcave lens close to the LCD, the thickness of the biconvex lens is smaller than 21mm, and the focal length is smaller than-1000 mm.

Preferably, the second lens has a thickness of greater than 8mm and a focal length of greater than 130mm.

Preferably, the first lens thickness is greater than 3.5mm and the focal length is less than 450mm.

Preferably, the LCD is a 4.3 inch, 4.5 inch, 5 inch, or 5.2 inch LCD;

when the LCD is a 4.3 inch LCD, the projection ratio is 1.29;

when the LCD is a 4.5 inch LCD, the projection ratio is 1.27;

when the LCD is a 5-inch LCD, the projection ratio is 1.13;

when the LCD is a 5.2 inch LCD, the throw ratio is 1.09.

After the scheme is adopted, the invention has the following advantages: the invention (1) increases the size of the light source window, uses the LCD of 5.2 inch large size specification; (2) enlarging the clear aperture of the lens; (3) The relative aperture of the lens is reduced, and the optical material is reduced to absorb light by adopting a glass and resin mixed lens; (4) The surface of the lens is plated with an antireflection film, so that the transmittance of the surface of the lens reaches more than 99%, and the reflection of light rays on the surface of the lens is reduced; through the mode, the brightness of the LCD projector is improved;

on the other hand, the invention (5) increases the number of the projection lens lenses, and increases the number of the lenses from 3 lenses to 6 lenses; (6) Adding an aspheric lens, and adding 8 optimization variables of image quality; (7) Taking the curvature of the Fresnel lens as a variable to perform aberration correction; (8) adopting a cemented lens to reduce chromatic aberration; (9) The circular diaphragm is changed into a rectangular diaphragm, so that the influence of stray light on image quality is reduced, and the contrast of an image is increased; (10) The refractive index of the glass material in the lens is larger than 1.6, and the resin material is optical PMMA; (10) the lens of the invention adopts 6 lenses of 5 groups; through the mode, the resolution of the LCD is improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are needed in the embodiments will be briefly described below, it being understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and that other related drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic diagram of a lens compatible with a multi-size LCD display screen according to the present invention.

Fig. 2 is a schematic view of a lens optical path of a lens compatible with a multi-size LCD display screen according to the present invention.

Fig. 3 is a schematic MTF diagram of a lens compatible with a multi-size LCD display screen according to the present invention.

Fig. 4 is a dot-column diagram of a lens compatible with a multi-size LCD display screen according to the present invention.

Fig. 5 is a distortion and field curvature diagram of a lens compatible with a multi-size LCD display screen according to the present invention.

Fig. 6 is a color difference diagram of a lens compatible with a multi-size LCD display screen according to the present invention.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments of the present invention. The components of the embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the invention, as presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further definition or explanation thereof is necessary in the following figures.

In the description of the embodiments of the present invention, it should be noted that, if the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate an azimuth or a positional relationship based on that shown in the drawings, or an azimuth or a positional relationship in which the product of the present invention is conventionally put when used, it is merely for convenience of describing the present invention and simplifying the description, and it does not indicate or imply that the apparatus or element to be referred to must have a specific azimuth, be configured and operated in a specific azimuth, and thus should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used merely to distinguish between descriptions and should not be construed as indicating or implying relative importance.

Furthermore, the terms "horizontal," "vertical," "overhang" and the like, if any, do not denote a requirement that the component be absolutely horizontal or overhang, but rather may be slightly inclined. As "horizontal" merely means that its direction is more horizontal than "vertical", and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.

In the description of the embodiments of the present invention, "plurality" means at least 2.

In the description of the embodiments of the present invention, it should also be noted that, unless explicitly specified and limited otherwise, the terms "disposed," "mounted," "connected," and "connected" should be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.

Examples

Referring to fig. 1-6, the present embodiment discloses a lens compatible with a multi-size LCD display screen, comprising a fresnel lens 2, a first lens 3, a second lens 4, a double-cemented lens 5, a diaphragm 6, a third lens 7 and a fourth lens 8, which are sequentially arranged from an LCD end 1 to a screen end 9; the fourth lens 8 is a positive meniscus lens, the third lens 7 is an 8-order aspherical lens, the second lens 4 is a biconvex lens, and the first lens 3 is an 8-order aspherical negative lens.

The thickness of the fourth mirror is smaller than 16mm, and the focal length is larger than 130mm; the thickness of the center of the third lens 7 is less than 9mm, and the focal length is less than-320 mm; the third lens 7 and the double-cemented lens 5 are arranged at intervals, the optical interval is larger than 22mm, and the diameter of the diaphragm 6 is 46.3mm; the double-glued lens 5 is a biconcave lens and a biconvex lens, the biconvex lens is arranged on one side of the biconcave lens close to the LCD, the thickness of the double-glued lens 5 is less than 21mm, and the focal length is less than-1000 mm; the thickness of the second lens 4 is more than 8mm, and the focal length is more than 130mm; the thickness of the first lens 3 is more than 3.5mm, and the focal length is less than 450mm; in the embodiment, the number of the projection lens is increased, 6 lenses are used, meanwhile, an aspheric lens is added, 8 image quality optimization variables are increased, the curvature of the Fresnel lens 2 is used as a variable to perform aberration correction, a cemented lens is adopted to reduce chromatic aberration, the circular diaphragm 6 is changed into a rectangular diaphragm 6, the influence of stray light on the image quality is reduced, the contrast of an image is increased, and the resolution of an LCD projector can be improved; in addition, increase the clear aperture of the lens, reduce the relative aperture of the lens, can improve the luminance of LCD projector, adopt glass, resin to mix the lens, reduce the absorption of the light of the optical material.

The LCD is 4.3 inch, 4.5 inch, 5 inch or 5.2 inch LCD; when the LCD is 4.3 inch LCD, its projection ratio is 1.29; when the LCD is a 4.5 inch LCD, the projection ratio is 1.27; when the LCD is a 5 inch LCD, the projection ratio is 1.13; when the LCD is a 5.2 inch LCD, the projection ratio is 1.09; in practice, the size of the light source window can be increased by using a 5.2 inch large-sized LCD.

The surfaces of the Fresnel lens 2, the first lens 3, the second lens 4, the double-cemented lens 5, the third lens 7 and the fourth lens 8 are plated with an antireflection film which enables the transmittance of the lens surface to reach more than 99%, and the reflection of the light on the lens surface can be reduced.

The focal length range of the LCD projection lens is 120-130 mm; the relative aperture of the LCD projection lens is smaller than f/2.0; the angle of view of the LCD projection lens is greater than 58 degrees, and its MTF is >4.6LP/mm within 0.93 field of view when the LCD is a 5.2 inch LCD.

The focal length of the Fresnel lens 2 is equal to 0.9-1.1 times of the focal length value of the lens; when the projection distance is 1.4 meters, the optical distance between the lens and the Fresnel lens is 80.5, and the optical distance between the Fresnel lens and the LCD is 13.

The invention and its embodiments have been described above with no limitation, and the actual construction is not limited to the embodiments of the invention as shown in the drawings. In summary, if one of ordinary skill in the art is informed by this disclosure, a structural manner and an embodiment similar to the technical solution should not be creatively devised without departing from the gist of the present invention.

Claims

1. The lens compatible with the multi-size LCD display screen is characterized by comprising a Fresnel lens, a first lens, a second lens, a double-cemented lens, a diaphragm, a third lens and a fourth lens which are sequentially arranged from an LCD end to a screen end; the fourth lens is a positive meniscus lens, the third lens is an 8-order aspheric lens, the second lens is a biconvex lens, and the first lens is an 8-order aspheric negative lens.

2. The multi-size compatible LCD screen lens of claim 1 wherein the fourth mirror is less than 16mm thick and has a focal length greater than 130mm.

3. The lens of claim 1, wherein the third lens has a center thickness of less than 9mm and a focal length of less than-320 mm; the third lens and the double-cemented lens are arranged at intervals, the optical interval is larger than 22mm, and the diameter of the diaphragm is 46.3mm.

4. The lens of claim 1, wherein the biconvex lens is a biconcave lens and a biconvex lens, the biconvex lens is arranged on one side of the biconcave lens close to the LCD, the thickness of the biconvex lens is less than 21mm, and the focal length is less than-1000 mm.

5. The multi-size compatible LCD screen lens of claim 1 wherein the second lens has a thickness greater than 8mm and a focal length greater than 130mm.

6. The multi-size compatible LCD screen lens of claim 1 wherein the first lens thickness is greater than 3.5mm and the focal length is less than 450mm.

7. The multi-size compatible LCD display screen lens of claim 1 wherein the LCD is a 4.3 inch, 4.5 inch, 5 inch or 5.2 inch LCD;

when the LCD is a 4.3 inch LCD, the projection ratio is 1.29;

when the LCD is a 4.5 inch LCD, the projection ratio is 1.27;

when the LCD is a 5-inch LCD, the projection ratio is 1.13;

when the LCD is a 5.2 inch LCD, the throw ratio is 1.09.

8. The lens of claim 1, wherein the fresnel lens, the first lens, the second lens, the double-cemented lens, the third lens and the fourth lens are each coated with an antireflection film to achieve a transmittance of 99% or more.

9. The multi-size compatible LCD screen lens of claim 1 wherein the LCD projection lens has a focal length in the range of 120-130 mm; the relative aperture of the LCD projection lens is smaller than f/2.0; the angle of view of the LCD projection lens is greater than 58 degrees, and when the LCD is a 5.2 inch LCD, the MTF is >4.6LP/mm within the 0.93 field of view.

10. The lens of claim 1, wherein the fresnel lens has a focal length equal to 0.9-1.1 times the focal length of the lens; when the projection distance is 1.4 meters, the optical distance between the lens and the Fresnel lens is 80.5, and the optical distance between the Fresnel lens and the LCD is 13.