CN102590992B - High-resolution large-fov (field of view) zoom projection lens - Google Patents

Abstract

The invention relates to a zoom projection lens with high resolution and large field of view. The lens group of the optical system includes a front compensation lens group, a zoom lens group, a rear compensation lens group and a rear compensation lens group arranged in sequence along the optical axis from the screen to the image plane DMD chip. Fixed lens group; the zoom lens group is a positive focal length component; both the front compensation lens group and the rear compensation lens group are negative focal length components; the rear fixed lens group is a positive focal length component; the front compensation lens group contains three lenses ; The variable power lens group contains two lenses; the rear compensation lens group contains two lenses; the rear fixed lens group contains six lenses; the rear fixed lens group has a diaphragm. The invention has the advantages of reasonable focal power distribution of each lens group, compact structure, large field of view, high resolution, and good imaging quality, and is used for high resolution of large screens based on 2k-4k digital micromirror array (DMD) chips High-efficiency projection lens has remarkable effect; lens materials are easy to process and suitable for mass production.

Description

High resolution large field of view zoom projection lens

technical field

The invention relates to a high-resolution large-field-of-view zoom projection lens, which is a large-field-of-view zoom projection lens suitable for use on a DLP projector with a high-resolution DMD chip, and is particularly suitable for use on a 4K high-resolution DMD chip. Large field of view zoom projection lens used on DLP projectors.

Background technique

In recent years, digital film is a technological revolution in the field of film technology. It is a brand-new model different from film films, and it presents the highest-quality images to the audience. With its strong advantages in production, distribution, and projection, it has developed rapidly in the industry. Therefore, there is a strong demand in the market for digital cinema projector systems and their supporting projection lenses.

The existing digital cinema projector mainly adopts two kinds of technical approaches: DLP (Digital Light Processing, digital light processing) technology and LCOS (Liquid Crystal On Silicon, liquid crystal on silicon) technology. The digital cinema widely used in digital cinema at present Most of the movie projection systems use DLP technology based on three DMD black chips. DLP technology is based on a digital micromirror device (DMD, Digital Micro-mirror Device) chip, and its basic principle is to directly project light onto millions of tiny mirrors , the micromirror corresponds to the pixel one by one, the deflection angle of the micromirror is controlled at high speed by using the digital image signal, and whether the reflected light of the micromirror can be projected to the optical display system acts as an optical switch, and a grayscale image is formed according to the proportion of the switch state , the red, green, and blue light generated by the three DMDs are synthesized to produce brightly colored images, which have excellent characteristics such as high brightness and high contrast. At present, 2k (2048×1080) DMD chips are widely used in theaters. And 4k (4096×2160) DMD chips are being gradually promoted in high-end theaters.

The projection lens is an important part of a digital cinema projector. The main function of the projection lens is to project the synthetic image of the three primary colors emitted by the digital chip onto the wide screen. The requirements of the digital cinema projection system for the projection lens are to be able to adapt to high-resolution projection and require good image quality; to be able to meet the requirements of special screens such as giant screens, and to require a large field of view; to be able to adapt to different size requirements of different theaters and screens , the lens can be zoomed; high light energy utilization efficiency requires high lens transmittance; it is required that the edges of each field of view can be seen clearly in the projection screen, and it is required that each field of view of the lens has better imaging quality and better Illumination uniformity; the image plane in the entire projection screen is required to be undistorted, and the image distortion that can be perceived by the vision does not occur, and the system is required to have small distortion; there is a prism group between the projection lens and the DMD chip, and the lens is required to have a long post-work distance. Therefore, the special requirements of the projection lens make it different from the development of ordinary optical systems.

In addition, in the existing disclosed projection lens technology, it is difficult to have a high image quality at 72lp/mm, and it cannot be better applied to the digital movie projection system based on the 4k DMD chip; spherical, but the image quality is still not good enough to guarantee a good projection effect in the digital cinema projection system based on 4k DMD chips; The disadvantages of system materials being limited by material supply and demand and high material prices are eliminated. High-resolution projection lenses require high image quality, uniform illumination, a certain zoom ratio, and long rear working distances, which bring difficulties to the design of projection lenses.

Contents of the invention

The purpose of the present invention is to provide a zoom projection lens with high resolution and large field of view, which has high imaging quality, can be matched with 2k ~ 4k DMD digital micromirror devices, has a large field of view, and can meet the needs of high-end giant screen theaters , especially can be used in a large-field high-resolution giant-screen digital cinema projection system based on a 4k DMD chip.

Technical scheme of the present invention is:

A high-resolution large field of view zoom projection lens, including an optical system lens group, the optical system lens group includes a front compensation lens group and a zoom lens arranged in sequence along the optical axis from the front screen to the rear image plane DMD chip group, rear compensation lens group and rear fixed lens group; the variable power lens group is a positive focal length component, used to realize variable power; the front compensation lens group and the rear compensation lens group are negative focal length components, used for moving The image quality compensation after zooming keeps the image plane stable during the zooming process; the rear fixed lens group is a positive focal length component, which is used to improve the overall image quality of the system; the front compensation lens group contains three lenses, which are in order from front to back : No. 1 lens is a positive lens, No. 2 lens is a negative lens, and No. 3 lens is a negative lens; the variable power lens group contains two lenses, and the order from front to back is: No. 4 lens is a negative lens, and No. The No. 5 lens of the lens; the rear compensation lens group contains two lenses, which are in order from front to back: No. 6 lens is a negative lens, and No. 7 lens is a positive lens; the rear fixed lens group contains six lenses. Yes: lens No. 8 as negative lens, lens No. 9 as positive lens, lens No. 10 as positive lens, lens No. 11 as negative lens, lens No. 12 as positive lens, and lens No. 13 as positive lens; There is a diaphragm in the rear fixed lens group.

Further technical solutions are:

The aperture of the high-resolution large-field-of-view zoom projection lens is located between the No. 9 lens and the No. 10 lens of the rear fixed lens group.

The high-resolution large-field-of-view zoom projection lens has a high-order aspheric lens before and after the diaphragm, which are used to reduce or eliminate various high-order aspheric lenses produced by the lenses before and after the diaphragm. Aberrations, improve the transfer function of the system, and maintain the imaging quality of the system.

In the high-resolution large-field zoom projection lens, the high-order aspherical surface of the high-order aspheric lens is set on the lens made of F6 and QK3 glass materials that are conducive to aspheric surface processing.

The high-resolution large field of view zoom projection lens, the high-order aspheric lens before the diaphragm is the No. 8 lens in the rear fixed lens group; the high-order aspheric lens behind the diaphragm is the No. 8 lens in the rear fixed lens group No. 12 lens.

In the high-resolution large field of view zoom projection lens, the No. 1 lens material of the front compensation lens group is K9, the No. 2 lens material is QK3, and the No. 3 lens material is CAF2; the No. 4 lens material of the zoom lens group is ZF12 , the material of No. 5 lens is LAF8; the material of No. 6 lens of the rear compensation lens group is K9, the material of No. 7 lens is ZF6; the material of No. 8 lens of the rear fixed lens group is F6, the material of No. 9 lens is ZF6, and the material of No. 10 lens It is CAF2, the lens material of No. 11 is F5, the material of lens No. 12 is QK3, and the material of lens No. 13 is CAF2.

In the high-resolution large-field-of-view zoom projection lens, the diameter of the No. 1 lens of the front compensation lens group is 130-150 mm, and the distance between the No. 2 lens and the No. 3 lens is 15-30 mm.

In the high-resolution large-field-of-view zoom projection lens, the focal length f of the lens group of the optical system is 28-35 millimeters, and the lens projection ratio TR is 1-1.25:1.

The high-resolution large-field-of-view zoom projection lens has a system focal length f of 30-35 mm and a lens projection ratio TR of 1-1.17:1.

The high-resolution large-field-of-view zoom projection lens has a system focal length f of 28 mm and a lens throw ratio TR of 1:1.

The high-resolution large-field-of-view zoom projection lens has a system focal length f of 35 mm and a lens throw ratio TR of 1.25:1.

Outstanding features and remarkable beneficial effects of the present invention are:

1. The present invention has the characteristics of high transfer function, good image quality, convenient focusing, and large field of view, and is suitable for large-screen digital movies based on 2k-4k DMD chips with large target size, large field of view, and high resolution in the projection system.

2. The lens group of the optical system of the present invention has 13 lenses, and all materials come from a wide range of sources, which is convenient for material supply and mass production, and the material cost and processing and manufacturing cost of the system are low.

3. Through the setting of high-order aspheric surface, the spherical aberration and high-order aberration are eliminated, the transfer function of the system is improved, and the system still has good imaging quality at 72lp/mm, and can be used at high resolution of 2k-4k DMD chips get excellent results. The high-order aspheric surface is set on the F6 and QK3 materials processed by the aspheric surface, and can be milled and polished by CNC machine tools to obtain a better part surface.

4. Reduce the chromatic aberration of the front compensation lens group through the combination of positive and negative lenses with different dispersion coefficients, which is conducive to the optimization of the image quality of the entire system; through the combination of ordinary glass materials and low dispersion CaF2 materials in the front compensation lens group and rear fixed lens group Eliminate chromatic aberration to eliminate system chromatic aberration and improve system image quality.

5. By using the commonly used low-dispersion CAF2 material to replace the low-dispersion fluorine crown glass, which is difficult to purchase and is not easy to process, it can not only meet the achromatic function of the system, but also facilitate the processing and mass production of the system lens.

Description of drawings

Fig. 1 Structural schematic diagram of zoom projection lens of the present invention

Fig. 2a is an optical schematic diagram of the short-focus part of the zoom projection lens of the present invention;

Fig. 2b is an optical schematic diagram of the focal part of the zoom projection lens of the present invention;

Fig. 2c is an optical schematic diagram of the telephoto part of the zoom projection lens of the present invention;

Fig. 3a is the distortion curve diagram when the zoom projection lens of the present invention is in the short focus position;

Fig. 3b is a distortion curve diagram when the zoom projection lens of the present invention is in the middle focus position;

Fig. 3c is a distortion curve diagram when the zoom projection lens of the present invention is in the telephoto position;

Fig. 4a is the transfer function diagram when the zoom projection lens of the present invention is in the short focus position;

Fig. 4b is the transfer function diagram when the zoom projection lens of the present invention is in the middle focus position;

Fig. 4c is the transfer function diagram when the zoom projection lens of the present invention is at the telephoto position.

The names of the markers in the figure are as follows:

L1—front compensation lens group; 1—1 lens; 2—2 lens; 3—3 lens;

L2—variable lens group; 4—4 lens; 5—5 lens;

L3—post-compensation lens group No. 6-6 lens; No. 7-7 lens;

L4—rear fixed lens group No. 8-8 lens; No. 9-9 lens; No. 10-10 lens; No. 11-11 lens; No. 12-12 lens; No. 13-13 lens;

14—Aperture.

Detailed ways

The present invention is further described as follows in conjunction with accompanying drawing and embodiment:

Embodiment 1: As shown in the figure, it is a basic embodiment of a high-resolution and large-field-of-view zoom projection lens of the present invention. The high-resolution large field of view has a resolution of 2k-4k, which is especially suitable for 4k and can also be used in 2k. The field of view ranges from 65.5° to 54.4°. The high-resolution large field of view zoom projection lens includes an optical system lens group, which includes a front compensation lens group L1, a variable magnification lens group arranged in sequence from the front screen to the rear image plane DMD chip along the optical axis Lens group L2, rear compensation lens group L3 and rear fixed lens group L4; the variable power lens group L2 is a positive focal length component for realizing variable power; both the front compensation lens group L1 and the rear compensation lens group L3 are negative focal lengths The component is used to move the image quality compensation after zooming and keep the image plane stable during the zooming process; the rear fixed lens group L4 is a positive focal length component used to improve the overall image quality of the system; the front compensation lens group L1 contains Three lenses, from front to back are: positive lens No. 1 lens, negative lens No. 2 lens, negative lens No. 3 lens; variable power lens group L2 contains two lenses, from front to back: The No. 4 lens is a negative lens, and the No. 5 lens is a positive lens; the rear compensation lens group L3 contains two lenses, which are in order from front to back: No. Lens group L4 contains six lenses, from front to back: lens No. 8 as negative lens, lens No. 9 as positive lens, lens No. 10 as positive lens, lens No. 11 as negative lens, lens No. 10 as positive lens No. 12 lens and No. 13 lens which is a positive lens; there is a diaphragm 14 in the rear fixed lens group L4. The aperture 14 is located between the No. 9 lens and the No. 10 lens of the rear fixed lens group L4. The front of the diaphragm 14 and the rear of the diaphragm 14 each have a high-order aspheric lens, which is used to reduce or eliminate various high-order aberrations produced by the lenses in front of the diaphragm 14 and behind the diaphragm 14, and improve the transmission of the system. Function, keep the system still has good imaging quality at 72lp/mm, and get a good use effect in 4k high-resolution DMD chips. The high-order aspherical surface of the high-order aspheric lens is set on the lens made of F6 and QK3 glass materials that are conducive to aspheric surface processing. The high-order aspheric lens before the diaphragm 14 is the No. 8 lens in the rear fixed lens group L4; the high-order aspheric lens behind the diaphragm 14 is the No. 12 lens in the rear fixed lens group L4. The No. 1 lens material of the aforementioned pre-compensation lens group L1 is K9, the No. 2 lens material is QK3, and the No. 3 lens material is CAF2. The combination of positive and negative lenses of different materials can correct the chromatic aberration of the pre-compensation lens group L1 and other various Aberration, optimize the image quality of the overall system; zoom lens group L2, its No. 4 lens material is ZF12, No. 5 lens material is LAF8, use high dispersion ZF12 as negative lens, use low dispersion LAF8 as positive lens, effectively reduce The chromatic aberration of the small zoom lens group; the material of the No. 6 lens of the rear compensation lens group L3 is K9, and the material of the No. 7 lens is ZF6; the material of the No. 8 lens of the rear fixed lens group L4 is F6, and the material of the No. 9 lens is ZF6. The lens material is CAF2, the lens material of No. 11 is F5, the material of lens No. 12 is QK3, and the material of lens No. 13 is CAF2. The zoom projection lens with high resolution and large field of view in this embodiment also has a cam drive mechanism with only one cam, and the front compensation lens group L1, the variable power lens group L2 and the rear compensation lens group L3 are three moving lens groups that are driven by the cam. Mechanism connection, the cam drive mechanism is a conventional mechanical compensating cam mechanism. For projection screens with different distances, the cam can drive the three moving lens groups to move as a whole to achieve zooming. The three moving lens groups maintain the long and short focus of each zoom position. The parfocality of each position, through the high-precision processing of the lens and the high-precision adjustment of the system, the actual system can ensure the parfocality of each zoom position. If there is a partial unclear situation in actual use, it will be controlled by the servo on the DMD. The mechanism moves the projection lens as a whole to achieve the purpose of fine-tuning the focus. The caliber of its No. 1 lens of described front compensation lens group L1 is 130～150 millimeters, and the interval distance between No. 2 lens and No. 3 lens is 15～30 millimeters, the enlargement of the caliber of No. 1 lens and No. 2 lens and No. 3 lens The increase in the distance between the No. 3 lenses makes the light in each field of view smooth, which is beneficial to reduce the tolerance sensitivity of the system and improve the final imaging quality of the system. The optical system lens group has a system focal length f of 28-35 mm, and a lens projection ratio TR of 1-1.25:1.

All glass used in the lens group of the optical system of the present invention is selected and easily obtained, and the system chromatic aberration is eliminated by combining and matching the chromatic aberration of different glasses. In particular, the large Abbe number and low dispersion of the CAF2 material are used to replace the hard-to-purchase and difficult-to-process fluorine crown glass to combine with other materials, which is beneficial to the supply and processing of optical lens materials in the mass production of the system .

To obtain high resolution, the zoom projection lens has high requirements on the transfer function MTF. The transfer function required by the zoom projection lens has a certain relationship with the pixel size of the DMD. For example: the number of pixels of DMD is x×y, the size of the target surface is c×d (unit: mm), then the size of a single pixel a is 1000c/x (unit: μm microns), then its requirement is 1000/(a ×2) (unit: lp/mm, line pair/mm), the transfer function has certain numerical requirements, and the general requirement is greater than 50%, that is: MTF>0.51000/2a (unit: lp/mm, line pair/mm). The number of pixels of the DMD is 4096×2160, the size of the target surface is 28×14.76 (mm), and the single pixel size a is 6.836 microns, so its requirement is 1000/(6.836×2), that is, 73.14lp/mm (take 72lp /mm, line pair/mm), the transfer function is greater than 50%, that is: MTF>0.572lp/mm. It can be seen from Figures 4a, 4b, and 4c that the values of the on-axis and off-axis transfer functions in this example are 72lp/mm, all reaching above 0.6, so the zoom projection lens has good imaging quality and can be better The application of 4k-based DMD high-resolution digital cinema projection equipment.

The relational expression between its lens projection ratio of the optical system lens group of the present invention and the target surface width size of projection distance, screen width, lens focal length, DMD is as follows:

                     

                     

In the formula:

PD——Projection distance

TR - Lens throw ratio Throw ratio

SW——screen width Screen width

f - system focal length

c - the width of the target surface of the DMD

In the case of keeping the projection distance PD value unchanged, the smaller the TR value, the larger the screen size; the larger the TR value, the smaller the screen size. In the case of constant target width c, the smaller the system focal length f is, the smaller the TR value is, and the larger the screen size is when the projection distance PD is constant. The f of the lens group of the optical system is 28~35 mm. When c is 28 mm, the projection ratio TR is 1~1.25:1, that is, when the projection distance PD is 25 meters, a screen width of 25 meters to 20 meters can be obtained , can meet the use requirements of giant screen theaters.

Fig. 2 a is the schematic diagram of the optical part of the short focus embodiment of the zoom projection lens of the present invention, in the figure, the distance between No. 3 lens and No. 4 lens is 120-110 millimeters, the distance between No. 5 lens and No. 6 lens is 0.3-10 millimeters The distance between the No. 7 lens and the No. 8 lens is 35-15 millimeters; Fig. 2 b is a schematic diagram of the optical part of an embodiment of the zoom projection lens of the present invention. In the figure, the distance between the No. 3 lens and the No. 4 lens is 110-105 millimeters, The distance between No. 5 lens and No. 6 lens is 10-35 millimeters, and the distance between No. 7 lens and No. 8 lens is 15-7 millimeters; Fig. 2 c is the schematic diagram of the optical part of the zoom projection lens telephoto embodiment of the present invention, No. 3 The distance between the lens and the No. 4 lens is 105-90 mm, the distance between the No. 5 lens and the No. 6 lens is 35-60 mm, and the distance between the No. 7 lens and the No. 8 lens is 7-0.5 mm.

In conjunction with the accompanying drawings, the short-focus, medium-focus, and telephoto technical effects of the high-resolution large-field zoom projection lens of the present invention are respectively explained as follows:

From the distortion curve of the zoom projection lens of the present invention when it is in the short focus position in Fig. 3a, it can be seen that the lens distortion is less than 1%, ASTZGMATIC astigmatism, FIELD CURVES field curvature, DISTORTION distortion;

From the distortion curve of the zoom projection lens of the present invention when it is in the middle focus position in Fig. 3b, it can be seen that the lens distortion is less than 1%, ASTZGMATIC astigmatism, FIELD CURVES field curvature, DISTORTION distortion;

From the distortion curve of the zoom projection lens of the present invention at the telephoto position in Fig. 3c, it can be seen that the lens distortion is less than 1%, ASTZGMATIC astigmatism, FIELD CURVES field curvature, DISTORTION distortion;

From the transfer function diagram of the zoom projection lens of the present invention when it is in the short focal position from Fig. 4a, it can be seen that the transfer function value of the lens at 72 lp/mm is greater than 0.6, MTF: transfer function, SPATIAL FREQUENCY: spatial frequency, CYCLES/MM: line pair/mm mm;

From the transfer function diagram of the zoom projection lens of the present invention when it is in the middle focus position in Fig. 4b, it can be seen that the transfer function value of the lens at 72 lp/mm is greater than 0.6, MTF: transfer function, SPATIAL FREQUENCY: spatial frequency, CYCLES/MM: line pair/mm mm;

From the transfer function diagram of the zoom projection lens of the present invention at the telephoto position in Fig. 4c, it can be seen that the transfer function value of the lens at 72 lp/mm is greater than 0.6, MTF: transfer function, SPATIAL FREQUENCY: spatial frequency, CYCLES/MM: line pair/mm mm.

Embodiment 2 : Different from the above embodiment 1, the focal length f of the system is 30-35 mm, and the lens projection ratio TR is 1-1.17:1.

Embodiment 3 : on the basis of above-mentioned embodiment 1, the selected system focal length f is 28 millimeters, and lens throw ratio TR is 1: 1, calculates according to formula, and the target face width dimension c of DMD is 28 millimeters, also promptly is suitable for 2k The zoom projection lens used on the DLP projector with a high-resolution DMD chip, according to the formula, it can be known that the projection distance of this embodiment is PD: 25 meters, and the screen width SW: 25 meters.

Embodiment 4 : on the basis of above-mentioned embodiment 1, the selected system focal length f is 35 millimeters, and lens projection ratio TR is 1.25: 1, calculates according to formula, and the target face width dimension c of DMD is 28 millimeters, also promptly is suitable for 4k The zoom projection lens used on the DLP projector with a high-resolution DMD chip, according to the formula, it can be known that the projection distance of this embodiment is PD: 25 meters, and the screen width SW: 20 meters.

The protection scope of the claims of the present invention is not limited to the above-mentioned embodiments.

Claims (8)

1. a kind of high-resolution large field of view zoom projection lens, comprise optical system lens group, it is characterized in that, described optical system lens group comprises the front of image plane DMD chip arranged sequentially along optical axis from front screen to rear image plane DMD chip Compensation lens group (L1), zoom lens group (L2), rear compensation lens group (L3) and rear fixed lens group (L4); the zoom lens group (L2) is a positive focal length component, used to realize zoom magnification; the front compensation lens group (L1) and the rear compensation lens group (L3) are both negative focal length components, which are used to compensate the image quality after zooming, and keep the image plane stable during the zooming process; the rear fixed lens group ( L4) is a positive focal length component, which is used to improve the overall image quality of the system; the front compensation lens group (L1) contains three lenses, from front to back: the No. 1 lens is a positive lens, and the No. 2 lens is a negative lens , No. 3 lens is a negative lens; zoom lens group (L2) contains two lenses, from front to back: No. 4 lens is a negative lens, No. 5 lens is a positive lens; rear compensation lens group (L3) Contains two lenses, from front to back: No. 6 lens, which is a negative lens, and No. 7 lens, which is a positive lens; the rear fixed lens group (L4) contains six lenses, from front to back: No. 8, which is a negative lens Lens #9, Lens #9 as positive lens, Lens #10 as positive lens, Lens #11 as negative lens, Lens #12 as positive lens, and Lens #13 as positive lens; rear fixed lens group (L4) There is a diaphragm (14) in the middle; the diameter of the No. 1 lens of the front compensation lens group (L1) is 130-150 mm, and the distance between the No. 2 lens and the No. 3 lens is 15-30 mm; The focal length f of the system is 28-35 mm, and the lens throw ratio TR is 1-1.25:1. 2. The high-resolution large field of view zoom projection lens according to claim 1, characterized in that the diaphragm (14) is located between the No. 9 lens and the No. 10 lens of the rear fixed lens group (L4). 3. The high-resolution large-field-of-view zoom projection lens according to claim 1 or 2, characterized in that there is a high-order aspheric lens in front of the diaphragm (14) and behind the diaphragm (14), which are used to reduce Or eliminate various high-order aberrations produced by the lens before the diaphragm (14) and after the diaphragm (14), improve the transfer function of the system, and maintain the imaging quality of the system. 4. The high-resolution large field of view zoom projection lens according to claim 3, characterized in that the high-order aspheric lens in front of the diaphragm (14) is the No. 8 lens in the rear fixed lens group (L4); The high-order aspheric lens behind the stop (14) is the No. 12 lens in the rear fixed lens group (L4). 5. The high-resolution large-field-of-view zoom projection lens according to claim 1, characterized in that the No. 1 lens material of the front compensation lens group (L1) is K9, the No. 2 lens material is QK3, and the No. 3 lens material is CAF2; zoom lens group (L2) whose No. 4 lens material is ZF12, No. 5 lens material is LAF8; rear compensation lens group (L3) whose No. 6 lens material is K9, and No. 7 lens material is ZF6; rear fixed lens group (L4) The No. 8 lens material is F6, the No. 9 lens material is ZF6, the No. 10 lens material is CAF2, the No. 11 lens material is F5, the No. 12 lens material is QK3, and the No. 13 lens material is CAF2. 6 . The high-resolution large-field-of-view zoom projection lens according to claim 1 , wherein the focal length f of the system is 30-35 millimeters, and the lens throw ratio TR is 1-1.17:1. 7. The high-resolution large-field-of-view zoom projection lens according to claim 1, wherein the focal length f of the system is 28 millimeters, and the lens throw ratio TR is 1:1. 8. The high-resolution large-field-of-view zoom projection lens according to claim 1, wherein the focal length f of the system is 35 millimeters, and the lens throw ratio TR is 1.25:1.

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