CN209803443U - Two-piece type projection lens - Google Patents

Abstract

The utility model provides a two formula projection lens, this projection lens include first lens, second lens and diaphragm, and first lens and second lens set up respectively in the both sides of diaphragm, the convex surface of first lens and the convex surface syntropy of second lens, and the convex surface of first lens and the convex surface of second lens are apart from the distance of diaphragm than do: 11:9.66. The utility model provides a projection lens is provided with first lens and second lens, and first lens and second lens set up the both sides at the diaphragm respectively to the convex surface of first lens and the convex surface syntropy of second lens define the ratio of the convex surface of first lens and the convex surface of second lens apart from the distance of diaphragm simultaneously as: 11:9.66, the 3.5 inch combined projection lens has clearer lens image quality and small chromatic aberration in the use process by arranging special lenses and the distance between the lenses and the diaphragm.

Description

Two-piece type projection lens

Technical Field

The utility model relates to a projection field particularly, relates to a two formula projection lens.

background

In principle, lenses of digital cameras and projectors are all optical lenses, all use the principle of light refraction, all use light-transmitting mirrors, and the essence of the lenses is the same, which is a similar point in the sense that the two lenses are the most basic optical devices. However, since the application properties and the effects to be obtained are different between the projector and the camera, they each show differences in specific detailed design and function:

The first difference is the device with or without the coil. For digital cameras, since the light sensing range of the light sensing device (CCD or CMOS) is very narrow, for these devices, it requires a device that controls the amount of incident light when the external light exceeds the light sensing range of the light sensing device,

The liquid crystal panel projector has the advantages of small volume, light weight, simple manufacturing process, high brightness and contrast and moderate resolution, and is the projector with the highest share and the most wide application in the current market. The assay environment was as follows: the distance between the projector and the screen is 2.4 meters; the screen was 60 inches; measuring the brightness of 9 points of a projection picture in a pure dark environment by using a light measuring pen; the average of the brightness of the 9 points was found to be ANSI lumens. At present, the nominal brightness of projectors of some domestic manufacturers is peak lumen, and the actual brightness is not high in the nominal value, which is a problem needing attention when selecting the projector. This is the diaphragm, which is made up of a set of very thin curved metal blades, which are mounted in the middle of the lens. The user can make the blades open and close uniformly by adjusting the aperture value, and adjust the blades into different apertures to control the light entering the lens so as to adapt to different shooting requirements. It should be noted that any camera may have an aperture. However, most projectors do not have an aperture, which is a device for controlling the amount of light flux. However, due to the development of projector technology in recent years, the aperture is also applied to the lens of the projector, typically the recently released PT-AE700 projector, which uses a "dynamic iris" technology, i.e. an aperture that can expand and contract with the brightness of the projected image, and the purpose of the aperture is to contract the aperture to reduce the projected light by times when the image appears dark in a large area, thus improving the contrast of the image. With advances in technology, it is believed that similar aperture techniques will add significant color to the projector.

The second difference is that the zoom ratio is very different: the projector is generally a fixed focus lens, and even a zoom lens projector, the zoom ratio is generally not more than 2, while the zoom ratio of a general consumer digital camera is generally more than 3, and only a very small number of digital cameras adopt a fixed focus lens or a lens with the zoom ratio less than 3.

The third difference is the difference of the lens calibers: the lens aperture of the digital camera is generally very small, while the lens aperture of the projector is very large. On the one hand, because the projector chips (LCD, DLP) are typically large, typically 1.3, 0.9, 0.7 inches, the required lens aperture is large to achieve the same aperture. While the chips (CCD, CMOS) on digital cameras are typically small, typically 1/4 inches, and the required lens aperture is small (f-number can be simply understood as the ratio of the focal length of the lens to the diameter of the optical lens) to obtain the same aperture. To obtain the smallest f-number (i.e., the largest aperture), the lens aperture is enlarged as much as possible. This results in a large aperture for the projector lens relative to the aperture of the digital camera. On the other hand, the reason is that the light flux required by the chip (CCD, CMOS) inside the digital camera is small (if not enough, manual light supplement is also available), the light flux required by the projector when meeting the requirement of people to watch is large, and no remedy is implemented when the brightness of the projector is insufficient! Therefore, the projector needs to use the maximum aperture (minimum aperture value), the maximum lens aperture, the maximum lamp power and other measures to ensure the realization of the minimum brightness value during the design, and during the design of the projector, the maximum value is not taken for the three parameters, but an optimal balance point is searched between the price and the performance.

For a lens, the most critical parameter, except for the difference in quality, is the size of the f value of the aperture, where f is the light transmittance of the lens. The larger the aperture f (the smaller the f value), the larger the light transmittance of the lens. The aperture of the projector lens is expressed in numerical values, generally from 1.6 to 4.0, and the maximum aperture of each lens is indicated in numerical values in front of the lens. It should be noted here that the value of f of the lens can reach 1.0 in an ideal state, and the value of f can never reach 1.0 due to the constraints of manufacturing process, price factors and the like.

for the projector, the lens is the last link in the optical path of the projector, the quality of the lens is good, the aperture value can be the minimum, the minimum aperture value and the brightness are in direct relation, the size of the aperture is in inverse proportion to the f value, and the smaller the f value is, the larger the aperture is. The brightness of the projected image is high, and for a fixed-focus lens, the aperture value is a constant value, and for a zoom lens, by definition of f value (the f value can be simply understood as the ratio of the focal length of the lens to the diameter of the optical lens), it can be seen that the value is in a range due to the change of the focal length. Such as f 2.8-f 3.4. The aperture value of a projector is a very important parameter, and for example, in the same projector, lenses with different f-numbers are used, and the difference of the brightness is very large! For example, the luminance of the f2.8 projector is twice that of the f4 projector, four times that of the f5.6 projector, and eight times that of the f8 projector … …. Any two lenses will transmit exactly the same amount of light as long as their f-values are the same. For example, if two different lenses are f/2.8, then the same amount of light will pass through the lenses to the screen. The f value of the projector is large, which is closely related to the focal length of the lens! It is possible that the f-number of a projector lens with a small aperture is smaller (the amount of light transmitted is larger) than that of a projector lens with a large aperture.

The focal length F is also expressed in numerical values, generally from 50 to 210, and is divided into short, standard and long, and ultra-short and ultra-long. The smaller the numerical value, the shorter the focal length, the larger the numerical value, the longer the focal length, the forward projection requirement of the projector on the focal length of the lens is generally 50-140, the rear projection is generally about 35, the focal length determines the distance between the projector and the film screen when the predetermined size is filled, the shorter the focal length, the closer the distance between the projector and the film screen, and the longer the distance is vice versa. If a large picture is projected at a short distance, a projector with a short focal length lens needs to be selected, and conversely, a projector with a long focal length lens needs to be selected. The typical projector is a standard lens.

The liquid crystal panel projector has the advantages of small volume, light weight, simple manufacturing process, high brightness and contrast and moderate resolution, and is the projector with the highest share and the most wide application in the current market. The assay environment was as follows: the distance between the projector and the screen is 2.4 meters; the screen was 60 inches; measuring the brightness of 9 points of a projection picture in a pure dark environment by using a light measuring pen; the average of the brightness of the 9 points was found to be ANSI lumens. At present, the nominal brightness of projectors of some domestic manufacturers is peak lumen, and the actual brightness is not high in the nominal value, which is a problem needing attention when selecting the projector. (of course, the conditions permit, but also the method of obtaining large-size projected images using refraction of the optical path on a standard lens projector may be considered.) for wide application sites, in the case of an abundance of capital, a telephoto lens is preferred because of the advantages of such an installation, firstly, the influence of the fan noise of the projector on the viewer is well suppressed, and secondly, the influence of the telephoto projector is minimal among the factors of the viewer's influence on the projector (smoker's soot, diner's food scraps, hot drink steam)! The projector also creates a comfortable working environment, and the projector is convenient to operate for a long service life. In the prior art, the focal length of the Fresnel mirror needs to be determined through experiments, but the effect is not ideal, so that the image quality of the lens is not clear, and the chromatic aberration is large.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a two formula projection lens, it can be through the setting of different lenses, make the camera lens image quality more clear, and the colour difference of projection is littleer.

The embodiment of the utility model is realized like this:

The utility model provides a two formula projection lens, this projection lens include first lens, second lens and diaphragm, and first lens and second lens set up respectively in the both sides of diaphragm, and the convex surface of first lens and the convex surface syntropy of second lens, the convex surface of first lens and the convex surface of second lens are apart from the distance ratio of diaphragm and are: 11:9.66.

In a preferred embodiment of the present invention, the projection lens further includes a plane penetration assembly and an image plane, and the plane penetration assembly and the image plane are disposed on one side of the concave surface of the second lens.

In a preferred embodiment of the present invention, the first lens includes a first convex surface and a first concave surface, and a ratio of a distance between the first convex surface and the first concave surface from the diaphragm is: 11:6.

In a preferred embodiment of the present invention, the second lens includes a second convex surface and a second concave surface, and a ratio of a distance between the second convex surface and the second concave surface from the diaphragm is: 9.5:17.35.

In a preferred embodiment of the present invention, a ratio of a distance between the first convex surface and the second convex surface to a distance between the first concave surface and the second concave surface is: 20.49:23.83.

In a preferred embodiment of the present invention, the ratio of the thicknesses of the first lens and the second lens is: 8.87:12.12.

In a preferred embodiment of the present invention, the ratio of the thicknesses of the first lens, the second lens and the planar through-hole assembly is: 8.87:12.12:10.6.

In a preferred embodiment of the present invention, the ratio of the distance between the second concave surface and the plane penetrating element to the distance between the image plane is: 103.36:115.16.

In a preferred embodiment of the present invention, the ratio of the edge thicknesses of the first lens and the second lens is: 4.23:6.31.

In a preferred embodiment of the present invention, the ratio of the center thicknesses of the first lens and the second lens is: 5:7.83.

The embodiment of the utility model provides a beneficial effect is: the utility model provides a projection lens is provided with first lens and second lens, and first lens and second lens set up the both sides at the diaphragm respectively to the convex surface of first lens and the convex surface syntropy of second lens, the convex surface of first lens and the convex surface of second lens are apart from the ratio of the distance in diaphragm and are: 11:9.66, the image quality of the 3.5-inch combined projection lens is clearer and the chromatic aberration is small in the use process.

Drawings

in order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention, and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

Fig. 1 is a schematic structural diagram of a two-piece projection lens according to an embodiment of the present invention;

Fig. 2 is a schematic structural view of a first lens according to an embodiment of the present invention;

Fig. 3 is a schematic structural view of a second lens according to an embodiment of the present invention.

Icon: 100-a first lens; 200-a second lens; 300-diaphragm; 400-plane penetration assembly; 500-image plane; 110-a first convex surface; 120-a first concave surface; 210-a second convex surface; 220-second concave surface.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, 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 obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention, as 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 present invention, presented in the accompanying drawings, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate the position or positional relationship based on the position or positional relationship shown in the drawings, or the position or positional relationship which is usually placed when the product of the present invention is used, and are only for convenience of description and simplification of the description, but do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used solely to distinguish one from another and are not to be construed as indicating or implying relative importance.

Furthermore, the terms "horizontal", "vertical", "overhang" and the like do not imply that the components are required to be absolutely horizontal or overhang, but may be slightly inclined. For example, "horizontal" merely means that the 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 present invention, it should also be noted that, unless otherwise explicitly specified or limited, the terms "disposed," "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

First embodiment

Referring to fig. 1, the present embodiment provides a two-piece projection lens, which includes a first lens 100, a second lens 200 and a diaphragm 300, wherein the first lens 100 and the second lens 200 are respectively disposed on two sides of the diaphragm 300, a convex surface of the first lens 100 and a convex surface of the second lens 200 are in the same direction, and a ratio of a distance between the convex surface of the first lens 100 and the convex surface of the second lens 200 and the diaphragm 300 is: 11:9.66.

The optical system parameters in this embodiment are as follows: focal length: 120 mm; throw ratio 1: 1.83; the posterior intercept (distance of the concave surface of the second lens 200 from the planar penetrating component) 103.36 mm; the distance from the rear surface of the planar penetration assembly to the display screen is: 10.6 mm; relative aperture F3.74; the effective aperture of the lens is 36.6 mm; the total lens length is 132.86 mm; when the throw distance was 1.2 meters, the screen was 31.1 inches. When the projection distance is 2 meters, the screen is 53.9 inches; when the projection distance is 0.8 m, the distance from the center of the last surface of the lens to the surface of the display screen is 122.7. When the projection distance is 2 meters, the distance from the center of the last surface of the lens to the surface of the display screen is 109.8; the parameters of the transfer function are as follows: the total field of view is 2.63lp/mm 0.5; the field of view is within 3.277lp/mm 0.5; distortion: full field of view < 0.02%; dot-column diagram: the diameter of the dispersion circle is less than 0.19; color difference: green: less than 0.16; red: less than 0.24; blue color: less than 0.32.

In a preferred embodiment of the present invention, the projection lens further includes a plane penetration assembly 400 and an image plane 500, and the plane penetration assembly 400 and the image plane 500 are disposed on the concave side of the second lens 200. In the present embodiment, the planar transmissive component 400 employs a fresnel mirror, and the image plane 500 is a display screen.

In a preferred embodiment of the present invention, the first lens 100 includes a first convex surface 110 and a first concave surface 120, and a ratio of a distance between the first convex surface 110 and the first concave surface 120 and the light stop 300 is: 11:6.

in a preferred embodiment of the present invention, the second lens 200 includes a second convex surface 210 and a second concave surface 220, and a ratio of a distance between the second convex surface 210 and the second concave surface 220 and the light stop 300 is: 9.5:17.35.

in a preferred embodiment of the present invention, a ratio of a distance between the first convex surface 110 and the second convex surface 210 to a distance between the first concave surface 120 and the second concave surface 220 is: 20.49:23.83.

In a preferred embodiment of the present invention, the ratio of the thicknesses of the first lens 100 and the second lens 200 is: 8.87:12.12.

In a preferred embodiment of the present invention, the ratio of the thicknesses of the first lens 100, the second lens 200 and the planar through-assembly 400 is: 8.87:12.12:10.6.

In a preferred embodiment of the present invention, the ratio of the distance between the second concave surface 220 and the plane penetrating component 400 and the image plane 500 is: 103.36:115.16.

In a preferred embodiment of the present invention, the ratio of the edge thicknesses of the first lens 100 and the second lens 200 is: 4.23:6.31.

In a preferred embodiment of the present invention, the ratio of the center thicknesses of the first lens 100 and the second lens 200 is: 5:7.83.

To sum up, the utility model provides a projection lens is provided with first lens and second lens, and first lens and second lens set up the both sides at the diaphragm respectively to the convex surface of first lens is syntropy with the convex surface of second lens, and the ratio of the convex surface of first lens and the convex surface of second lens apart from the distance of diaphragm is defined as simultaneously: 11:9.66, the 3.5 inch combined projection lens has clearer lens image quality and small chromatic aberration in the use process by arranging special lenses and the distance between the lenses and the diaphragm.

This description describes examples of embodiments of the invention, and is not intended to illustrate and describe all possible forms of the invention. It should be understood that the embodiments described in this specification can be implemented in many alternative forms. The figures are not necessarily to scale; some features may be exaggerated or minimized to show details of particular components. Specific structural and functional details disclosed are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present invention. It will be appreciated by persons skilled in the art that a plurality of features illustrated and described with reference to any one of the figures may be combined with features illustrated in one or more other figures to form embodiments which are not explicitly illustrated or described. The described combination of features provides a representative embodiment for a typical application. However, various combinations and modifications of the features consistent with the teachings of the present invention may be used as desired for particular applications or implementations.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (5)

1. The utility model provides a two formula projection lens, its characterized in that, projection lens includes first lens, second lens and diaphragm, first lens with the second lens sets up respectively the both sides of diaphragm, the convex surface of first lens with the convex surface syntropy of second lens, the convex surface of first lens with the convex surface distance of second lens the ratio of the distance of diaphragm is: 11: 9.66; the projection lens further comprises a plane penetration assembly and an image plane, wherein the plane penetration assembly and the image plane are arranged on the concave surface side of the second lens; the first lens comprises a first convex surface and a first concave surface, and the distance ratio of the first convex surface to the first concave surface to the diaphragm is as follows: 11: 6; the second lens comprises a second convex surface and a second concave surface, and the ratio of the distance from the second convex surface to the second concave surface to the diaphragm is as follows: 9.5: 17.35; the ratio of the distance between the first convex surface and the second convex surface to the distance between the first concave surface and the second concave surface is: 23.83, 20.49: 23.83; the ratio of the thicknesses of the first lens and the second lens is: 8.87:12.12.

2. The two-piece projection lens of claim 1 wherein the ratio of the thicknesses of the first lens, the second lens, and the planar penetration assembly is: 8.87:12.12:10.6.

3. The two-piece projection lens of claim 1, wherein the second concave surface is spaced apart from the plane-passing element and the image plane by a ratio of: 103.36:115.16.

4. The two-piece projection lens of claim 1, wherein the ratio of the edge thicknesses of the first lens and the second lens is: 4.23:6.31.

5. The two-piece projection lens of claim 1, wherein the ratio of the center thicknesses of the first and second lenses is: 5:7.83.