Zoom projection optical system and projection apparatus

Abstract

The utility model discloses a zoom projection optical system and projection equipment, and relates to the technical field of optics, and the zoom projection optical system is provided with an object side and an image side which are oppositely arranged along the direction of an optical axis. The zoom projection optical system comprises a plurality of lens groups, a galvanometer, an equivalent prism and a display chip which are sequentially arranged from the object side to the image side, the plurality of lens groups comprise a first lens group with negative focal power, a second lens group with positive focal power, a third lens group with positive focal power, a fourth lens group with positive focal power and a fifth lens group with positive focal power; wherein the first lens group moves along the direction of the optical axis to realize focusing, and at least one of the second lens group, the third lens group and the fourth lens group can move along the direction of the optical axis to enable the zoom lens to zoom, so that the zoom projection optical system has the effects of small size, low projection ratio initial value and few zoom groups.

Description

Technical Field

[0001] The utility model relates to the technical field of optics, in particular to a zoom projection optical system and projection equipment. Background Art

[0002] With the development of technology, projectors are widely used in education, home use and other fields. Among them, zoom projection lenses can change the size of the picture without changing the projection distance, and their flexibility is highly favored by consumers.

[0003] As the core component of the projector, the lens determines the range of the picture size. The zoom projection lenses on the market are generally large in size, which will cause the overall projector to be relatively large. In order to meet the larger magnification, the lens generally adopts more group linkage, which is difficult to manufacture. At the same time, the starting data of the existing large-magnification lens projection ratio is generally greater than 1.2, which is difficult to adapt to the space requirements of different scenes. Utility Model Content

[0004] The main purpose of the utility model is to provide a zoom projection optical system and a projection device, aiming to provide a zoom projection optical system with a small volume, a low projection ratio starting value and a small number of zoom groups.

[0005] To achieve the above object, the utility model proposes a zoom projection optical system, wherein the zoom projection optical system has an object side and an image side which are arranged opposite to each other along the optical axis direction, and the zoom projection optical system comprises a plurality of lens groups, a galvanometer, an equivalent prism and a display chip which are sequentially arranged from the object side to the image side.

[0006] Wherein, the plurality of lens groups include:

[0007] A first lens group having negative optical power;

[0008] A second lens group having positive optical power;

[0009] A third lens group having positive optical power;

[0010] a fourth lens group having positive refractive power;

[0011] a fifth lens group having positive refractive power;

[0012] The first lens group moves along the optical axis to achieve focusing, and at least one of the second lens group, the third lens group, and the fourth lens group can move along the optical axis to enable the zoom lens to zoom.

[0013] In one embodiment, the focal length of the wide-angle end of the projection optical system is F W , the focal length F of the first lens group 100 is negative, the focal length F of the second lens group200 is positive; the focal length F of the third lens group 300 is positive; the focal length F of the fourth lens group 400 is positive; the focal length F of the fifth lens group 500 is positive; the focal length satisfies: 0.9<|F 100 / F W |<1.5,4<|F 200 / F W |<6,3<|F 300 / F W |<4,8<|F 400 / F W |<10,4<|F 500 / F W |<6;

[0014] The total optical length of the projection optical system, that is, the distance from one surface of the first lens to the surface of the display chip, is TTL, satisfying TTL≤116mm and TTL / FW≤12.3.

[0015] In one embodiment, the first lens group includes a first lens, a second lens, and a third lens arranged in sequence from the object side to the image side along the optical axis; the first lens has a negative optical power, the second lens has a negative optical power, and the third lens has a negative optical power.

[0016] In one embodiment, the second lens group includes a fourth lens having a positive optical power; the third lens group includes a fifth lens having a positive optical power; the fourth lens group includes an aperture, a sixth lens, a seventh lens, an eighth lens, a ninth lens, a tenth lens, an eleventh lens and a twelfth lens arranged in sequence from the object side to the image side along the optical axis, the sixth lens having a positive optical power, the seventh lens having a negative optical power, the eighth lens having a positive optical power, the ninth lens having a negative optical power, the tenth lens having a positive optical power, the eleventh lens having a positive optical power, and the twelfth lens having a positive optical power.

[0017] In one embodiment, the fifth lens group includes a thirteenth lens, and the thirteenth lens has positive optical power.

[0018] In one embodiment, the intervals between the plurality of lens groups satisfy the following relationship: 4.57 <L 12 <5.7, 16.18 <L 23 <16.18, 14.72 <L 34 <14.72, 0.1 <L 45 <8.21;

[0019] The distance between the first lens group and the second lens group is L 12 , the interval between the second lens group and the third lens group is L 23 , the interval between the third lens group and the fourth lens group is L 34 , the interval between the fourth lens group and the fifth lens group is L 45 .

[0020] In one embodiment, the lens power satisfies the following relationship:

[0021] In the first lens group: 0.02<|φ1|<0.04, 0.01<|φ2|<0.03, 0.03<|φ3|<0.04, in the second lens group: 0.02<|φ4|<0.03, in the third lens group: 0.02<|φ5|<0.04, in the fourth lens group: 0.01<|φ 67 |<0.02, 0.03<|φ8|<0.05, 0.03<|φ 91011 |<0.05, 0.015<|φ 12 |<0.03, in the fifth lens group: 0.02<|φ 13 |<0.03;

[0022] The focal power of the first lens is φ1, the focal power of the second lens is φ2, the focal power of the third lens is φ3, the focal power of the fourth lens is φ4, the focal power of the fifth lens is φ5, and the sum of the focal powers of the sixth lens and the seventh lens is φ 67 The focal power of the eighth lens is φ8, and the sum of the focal powers of the ninth lens, the tenth lens and the eleventh lens is φ 91011 ; The focal length of the twelfth lens is φ 12 , the optical focal length of the thirteenth lens is φ13.

[0023] In one implementation, the sixth lens and the seventh lens in the fourth lens group are configured as a doublet lens, and the ninth lens, the tenth lens, and the eleventh lens are configured as a triplet lens.

[0024] In one embodiment, the first lens is a plastic aspheric lens, the tenth lens is a glass aspheric lens, and the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, the eighth lens, the ninth lens, the eleventh lens, the twelfth lens, and the thirteenth lens are glass spherical lenses.

[0025] The utility model also provides a projection device, including a zoom projection optical system, wherein the zoom projection optical system has an object side and an image side that are arranged opposite to each other along an optical axis direction, and the zoom projection optical system includes a plurality of lens groups, a galvanometer, an equivalent prism and a display chip that are sequentially arranged from the object side to the image side.

[0026] Wherein, the plurality of lens groups include:

[0027] A first lens group having negative optical power;

[0028] A second lens group having positive optical power;

[0029] A third lens group having positive optical power;

[0030] a fourth lens group having positive refractive power;

[0031] a fifth lens group having positive refractive power;

[0032] The first lens group moves along the optical axis to achieve focusing, and at least one of the second lens group, the third lens group, and the fourth lens group can move along the optical axis to enable the zoom lens to zoom.

[0033] In the technical solution of the utility model, when the projection distance changes, the second lens group, the third lens group, the fourth lens group and the fifth lens group remain stationary, and the first lens group moves along the optical axis direction to achieve focusing and make the image clear; when the projection screen size / projection ratio needs to be changed, at least one of the second lens group, the third lens group and the fourth lens group moves along the optical axis toward the image side direction, so that the zoom projection optical system changes continuously from the wide-angle end to the telephoto end to achieve zooming; through the reasonable arrangement of the structure and position of the first lens assembly with negative optical power, the second lens group with positive optical power, the third lens group with positive optical power, the fourth lens group with positive optical power and the fifth lens group with positive optical power, the zoom projection optical system has the effects of small volume, low projection ratio starting value and few zoom groups. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0035] Figure 1A schematic structural diagram of a wide-angle end embodiment of a zoom projection optical system provided by the utility model;

[0036] Figure 2 for Figure 1 A schematic structural diagram of another embodiment of a medium zoom projection optical system at the long focal length;

[0037] Figure 3 for Figure 1 Schematic diagram of the magnification chromatic aberration curve of the medium zoom projection optical system at the wide-angle end;

[0038] Figure 4 for Figure 1 Schematic diagram of field curvature / distortion curve of a medium zoom projection optical system at the wide-angle end;

[0039] Figure 5 for Figure 1 Schematic diagram of the MTF curve of the medium zoom projection optical system at the wide angle end;

[0040] Figure 6 for Figure 2 Schematic diagram of the magnification chromatic aberration curve of the medium zoom projection optical system at the telephoto end;

[0041] Figure 7 for Figure 2 Schematic diagram of field curvature / distortion curve of a medium zoom projection optical system at the telephoto end;

[0042] Figure 8 for Figure 2 Schematic diagram of the MTF curve of the medium zoom projection optical system at the telephoto end.

[0043] Description of Figure Numbers:

[0044] 100. Zoom projection optical system; 1. first lens group; 11. first lens; 12. second lens; 13. third lens; 2. second lens group; 21. fourth lens; 3. third lens group; 31. fifth lens; 4. fourth lens group; 41. sixth lens; 42. seventh lens; 43. eighth lens; 44. ninth lens; 45. tenth lens; 46. eleventh lens; 47. twelfth lens; 48. aperture; 5. fifth lens group; 51. thirteenth lens; 6. galvanometer; 7. equivalent prism; 8. display chip.

[0045] The realization of the purpose, functional features and advantages of the utility model will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0046] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0047] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back...), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0048] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the utility model, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of the features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the utility model.

[0049] As the core component of the projector, the lens determines the range of the picture size. The zoom projection lenses on the market are generally large in size, which will cause the overall projector to be relatively large. In order to meet the larger magnification, the lens generally adopts more group linkage, which is difficult to manufacture. At the same time, the starting data of the existing large-magnification lens projection ratio is generally greater than 1.2, which is difficult to adapt to the space requirements of different scenes.

[0050] In order to solve the above problems, the utility model provides a zoom projection optical system.

[0051] First of all, it can be understood that the focal length is equal to the difference between the convergence of the image-side light beam and the convergence of the object-side light beam, and it characterizes the ability of the optical system to deflect light. The larger the absolute value of the focal length, the stronger the ability to bend light, and the smaller the absolute value of the focal length, the weaker the ability to bend light. When the focal length is a positive number, the refraction of light is convergent; when the focal length is a negative number, the refraction of light is divergent. The focal length can be used to characterize a certain refractive surface of a lens (i.e., a surface of a lens), can be used to characterize a certain lens, and can also be used to characterize a system formed by multiple lenses (i.e., a lens group).

[0052] See also Figure 1 In one embodiment of the utility model, the zoom projection optical system includes an object side and an image side which are arranged opposite to each other along the optical axis direction, and the zoom projection optical system includes a first lens group 1 with negative optical power, a second lens group 2 with positive optical power, a third lens group 3 with positive optical power, a fourth lens group 4 with positive optical power, a fifth lens group 5 with positive optical power, a galvanometer 6, an equivalent prism 7 and a display chip 8 which are arranged in sequence from the object side to the image side, wherein the plurality of lens groups include a first lens group 1 with negative optical power, a second lens group 2 with positive optical power, a third lens group 3 with positive optical power, a fourth lens group 4 with positive optical power, and a fifth lens group 5 with positive optical power; the first lens group 1 moves along the optical axis direction to achieve focusing, and at least one of the second lens group 2, the third lens group 3, and the fourth lens group 4 can move along the optical axis direction to enable the zoom lens to zoom.

[0053] In the technical solution of the utility model, when the projection distance changes, the second lens group 2, the third lens group 3, the fourth lens group 4, and the fifth lens group 5 remain stationary, and the first lens group 1 moves along the optical axis direction to achieve focusing and make the image clear; when the projection screen size / projection ratio needs to be changed, at least one of the second lens group 2, the third lens group 3, and the fourth lens group 4 moves along the optical axis toward the image side direction, so that the zoom projection optical system continuously changes from the wide-angle end to the telephoto end to achieve zooming; through the reasonable arrangement of the structure and position of the first lens group 1 with negative optical focal power, the second lens group 2 with positive optical focal power, the third lens group 3 with positive optical focal power, the fourth lens group 4 with positive optical focal power, and the fifth lens group 5 with positive optical focal power, the zoom projection optical system has the effects of small volume, low projection ratio starting value, and few zoom groups.

[0054] Specifically, in one embodiment of the present invention, the focal length of the wide-angle end of the projection optical system is F W , the focal length F of the first lens group 1 100 is negative, the focal length F of the second lens group 2 200is positive; the focal length F of the third lens group 3 300 is positive; the focal length F of the fourth lens group 4 400 is positive; the focal length F of the fifth lens group 5 500 is positive; the focal length satisfies: 0.9<|F 100 / F W |<1.5,4<|F 200 / F W |<6,3<|F 300 / F W |<4,8<|F 400 / F W |<10,4<|F 500 / F W |<6; In addition, the total optical length of the projection optical system, that is, the distance from one side of the first lens 11 to the surface of the display chip 8 is TTL, satisfying TTL≤116mm, TTL / FW≤12.3, wherein the total optical length can be understood as the size of the entire optical projection system, and the focal length refers to the distance from the rear surface of the lens to the image plane in the optical system, and the focal length determines the magnification and viewing angle of the image; by conditionally restricting the focal length of the wide-angle end of the projection optical system and the focal length ratio of each lens group, an anti-telephoto structure is formed, and a smaller total length and a larger projection ratio range are obtained, so that the projection optical system can achieve a small volume and a larger adjustable range of the projection screen size to meet the space requirements of different scenes.

[0055] Furthermore, in an embodiment of the utility model, the first lens group 1 includes a first lens 11, a second lens 12, and a third lens 13 arranged in sequence from the object side to the image side along the optical axis; the first lens 11 has a negative optical power, the second lens 12 has a negative optical power, and the third lens 13 has a negative optical power. By limiting the positive and negative optical powers of the first lens 11, the second lens 12, and the third lens 13 in the first lens group 1, the height of the light entering the rear group is reduced, and the aberration of the off-axis system is reduced.

[0056] Further, in an embodiment of the present invention, the second lens group 2 includes a fourth lens 21, and the fourth lens 21 has a positive focal power; the third lens group 3 includes a fifth lens 31, and the fifth lens 31 has a positive focal power; the fourth lens group 4 includes an aperture 48, a sixth lens 41, a seventh lens 42, an eighth lens 43, a ninth lens 44, a tenth lens 45, an eleventh lens 46 and a twelfth lens 47, which are arranged in sequence from the object side to the image side along the optical axis direction, the sixth lens 41 has a positive focal power, the seventh lens 42 has a negative focal power, the eighth lens 43 has a positive focal power, the ninth lens 44 has a negative focal power, the tenth lens 45 has a positive focal power, the eleventh lens 46 has a positive focal power, and the twelfth lens 47 has a positive focal power. By arranging the fourth lens 21 and the fifth lens 31 is positive, increasing the entrance pupil entering the rear group, so that the system can achieve a larger aperture, providing more adjustable space for the aperture 48; the aperture 48 can perform corresponding aperture scaling measures as the ambient light intensity changes, and the aperture 48 is used to limit the light beam to further improve the imaging quality of the zoom lens; in addition, due to the particularity of multi-group zoom, compared with the traditional structure, at the telephoto end, when the aperture 48 is the same size, the aperture 48 will move with the fourth lens group 4, and the optical path from the first lens group 1 to the position of the aperture 48 is reduced, and the aperture of the front lens group is greatly reduced. Through sophisticated optical path design and structural arrangement, the goal of high-magnification zoom is achieved in a small volume; further, by limiting the positive and negative focal lengths of the lenses, the residual spherical aberration of the system is corrected, and at the same time, the light height of the off-axis field of view can be increased, so that the system has a larger target surface.

[0057] Furthermore, in one embodiment of the utility model, the fifth lens group 5 includes a thirteenth lens 51, and the thirteenth lens 51 has a positive optical power, which further corrects the system distortion and converges the aberration of a large field of view to realize a telecentric optical system, so that the system finally obtains a large target surface and obtains a higher imaging quality.

[0058] Further, in an embodiment of the present invention, it is necessary to understand that when the optical projection system is at the wide-angle end, the focal length is the shortest, and the spacing between the lens groups is the smallest. When the optical projection system is at the telephoto end, the focal length is the longest, and the spacing between the lens groups is also the largest. At the wide-angle end and the telephoto end, the optical projection system has different focal lengths and optical powers, and also has different lengths or shapes. When the optical projection system zooms from the wide-angle end to the telephoto end, in order to further improve the imaging effect, the second lens group 2, the third lens group 3, and the fourth lens group 4 are linked, and the intervals between the multiple lens groups satisfy the following relationship: 4.57 <L 12 <5.7, 16.18 <L 23 <16.18, 14.72 <L34 <14.72, 0.1 <L 45 <8.21; wherein the interval between the first lens group 1 and the second lens group 2 is L 12 , the interval between the second lens group 2 and the third lens group 3 is L 23 , the interval between the third lens group 3 and the fourth lens group 4 is L 34 , the interval between the fourth lens group 4 and the fifth lens group 5 is L 45 By limiting the intervals between the multiple lens groups, the focal plane position is guaranteed to remain unchanged during the zooming process, thereby achieving true zooming, that is, the imaging quality does not change substantially from the wide-angle end to the telephoto end during the zooming process.

[0059] In addition, in an embodiment of the present invention, the lens power satisfies the following relationship:

[0060] In the first lens group 1: 0.02<|φ1|<0.04, 0.01<|φ2|<0.03, 0.03<|φ3|<0.04, in the second lens group 2: 0.02<|φ4|<0.03, in the third lens group 3: 0.02<|φ5|<0.04, in the fourth lens group 4: 0.01<|φ 67 |<0.02, 0.03<|φ8|<0.05, 0.03<|φ 91011 |<0.05, 0.015<|φ 12 |<0.03, in the fifth lens group 5: 0.02<|φ 13 |<0.03;

[0061] The focal power of the first lens 11 is φ1, the focal power of the second lens 12 is φ2, the focal power of the third lens 13 is φ3, the focal power of the fourth lens 21 is φ4, the focal power of the fifth lens 31 is φ5, and the sum of the focal powers of the sixth lens 41 and the seventh lens 42 is φ 67 The focal length of the eighth lens 43 is φ8, and the sum of the focal lengths of the ninth lens 44, the tenth lens 45 and the eleventh lens 46 is φ 91011 The focal length of the twelfth lens 47 is φ 12 , the focal length of the thirteenth lens 51 is φ 13 ; According to this optical focal length distribution, the lens resolution is increased.

[0062] Furthermore, in an embodiment of the utility model, the sixth lens 41 and the seventh lens 42 in the fourth lens group 4 are configured as doublet lenses to correct axial chromatic aberration, and the ninth lens 44, the tenth lens 45 and the eleventh lens 46 are configured as triplet lenses to correct the magnification chromatic aberration of the system, so that the system obtains smaller chromatic aberration while increasing the light height of the off-axis field of view, so that the system has a larger target surface.

[0063] Further, in an embodiment of the present utility model, the first lens 11 is a plastic aspheric lens, the tenth lens 45 is a glass aspheric lens, the second lens 12, the third lens 13, the fourth lens 21, the fifth lens 31, the sixth lens 41, the seventh lens 42, the eighth lens 43, the ninth lens 44, the eleventh lens 46, the twelfth lens 47, and the thirteenth lens 51 are glass spherical lenses;

[0064] It can be understood that the characteristics of aspherical lenses are: the curvature changes continuously from the center of the lens to the periphery of the lens. Unlike spherical lenses with constant curvature from the center of the lens to the periphery of the lens, aspherical lenses have better curvature radius characteristics and have the advantages of improving distortion aberration and improving astigmatism aberration. After using aspherical lenses, the aberrations that occur during imaging can be eliminated as much as possible, thereby improving the imaging quality of the lens.

[0065] Specifically, in one embodiment of the present invention, the surface shape of the aspheric lens in the projection optical system should satisfy the following equation:

[0066]

[0067] Among them, c is the curvature corresponding to the radius; y is the radial coordinate (its unit is the same as the lens length unit); k is the conic quadratic curve coefficient, and A, B, C, D, E, F, G... represent the fourth-order, sixth-order, eighth-order, tenth-order, twelfth-order, fourteenth-order, sixteenth-order... aspheric coefficients respectively.

[0068] More specifically, in an embodiment of the present invention, the even-order coefficients of each aspherical surface are shown in Table 1 below.

[0069] Table 1

[0070] Face number k A B C D E F G 1 -17.5484 4.30898E-05 -1.46948E-07 3.70149E-10 -2.87188E-13 -6.74220E-16 1.42763E-18 -4.89878E-22 2 -0.34206 -1.96207E-05 1.16060E-07 -2.12005E-09 6.20680E-12 2.66034E-14 -2.30339E-16 3.23048E-19

[0071] The above parameters can be used to accurately set the shape and size of the aspheric surfaces of the front and back sides of the lens to correct distortion so that the system can obtain a projection ratio value less than or equal to 0.9. It can be understood that the projection ratio refers to the ratio between the projection distance of the projector and the width of the projection screen. The smaller the projection ratio, the wider the projection screen is at the same projection distance. Conversely, the larger the ratio, the smaller the width of the projection screen. Because the projection ratio data is smaller when projecting the same size of the screen, the projection distance is closer, so a lens with a smaller projection ratio is easier to meet the space requirements of different scenes; at the same time, the use of plastic lenses greatly reduces costs.

[0072] Furthermore, since glass lenses are expensive and difficult to manufacture, in this embodiment, the first lens 11 is made of K26R plastic, which has high transparency and excellent heat resistance. Its light transmittance is close to that of glass, and it maintains stable performance in high temperature environments, so that the projector does not defocus in a high-brightness working environment, greatly reducing costs while maintaining excellent optical performance.

[0073] Specifically, the tenth lens 45 is a glass aspheric surface, that is, the bonding surface between the tenth lens 45 and the ninth lens 44, and between the tenth lens 45 and the eleventh lens 46 is a glass aspheric surface, which is used to correct the pupil aberration caused by the large aperture, thereby improving the imaging quality of the system, and at the same time greatly reducing the number of spherical lenses set and reducing the system volume.

[0074] In addition, in an embodiment of the utility model, the second lens 12, the third lens 13, the fourth lens 21, the fifth lens 31, the sixth lens 41, the seventh lens 42, the eighth lens 43, the ninth lens 44, the eleventh lens 46, the twelfth lens 47, and the thirteenth lens 51 are glass spherical lenses. In order to improve the imaging quality of the lens at various magnifications, the utility model combines high-refractive-index glass with ultra-low-dispersion glass materials to reduce various optical aberrations while effectively suppressing the chromatic aberration of the system. At the same time, because the glass lens is not easily affected by thermal expansion and contraction and has a focus shift phenomenon, the glass lens can well resist the problem of thermal deformation of the lens and maintain the high precision of the lens for a long time. In addition, the aberration that occurs during imaging can be eliminated as much as possible, thereby improving the imaging quality of the lens and reducing the influence of temperature on the optical performance of the lens.

[0075] Specifically, in an embodiment of the present invention, the parameters of the zoom lens are shown in Table 2 below.

[0076] Table 2

[0077]

[0078]

[0079] The utility model also proposes a projection device, which includes a zoom projection optical system. The specific structure of the zoom projection optical system refers to the above-mentioned embodiment. Since the projection device adopts all the technical solutions of all the above-mentioned embodiments, it at least has all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be described one by one here.

[0080] The above description is only an exemplary embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A zoom projection optical system, characterized in that: The zoom projection optical system has an object side and an image side which are arranged opposite to each other along the optical axis direction, and the zoom projection optical system includes a plurality of lens groups, a galvanometer mirror, an equivalent prism and a display chip which are sequentially arranged from the object side to the image side. Wherein, the plurality of lens groups include: A first lens group having negative optical power; A second lens group having positive optical power; A third lens group having positive optical power; a fourth lens group having positive refractive power; a fifth lens group having positive refractive power; The first lens group moves along the optical axis to achieve focusing, and at least one of the second lens group, the third lens group and the fourth lens group can move along the optical axis to enable the zoom projection optical system to zoom.

2. The zoom projection optical system according to claim 1, characterized in that: The focal length of the wide-angle end of the projection optical system is F W , the focal length F of the first lens group 100 is negative, the focal length F of the second lens group 200 is positive; the focal length F of the third lens group 300 is positive; the focal length F of the fourth lens group 400 is positive; the focal length F of the fifth lens group 500 is positive; the focal length satisfies: 0.9<|F 100 / F W |<1.5,4<| F 200 / F W |<6,3<|F 300 / F W |<4,8<|F 400 / F W |<10,4<|F 500 / F W |<6; The total optical length of the projection optical system, that is, the distance from one surface of the first lens to the surface of the display chip, is TTL, satisfying TTL≤116mm and TTL / FW≤12.

3.

3. The zoom projection optical system according to claim 1, wherein: The first lens group includes a first lens, a second lens, and a third lens arranged in sequence from the object side to the image side along the optical axis; the first lens has a negative optical power, the second lens has a negative optical power, and the third lens has a negative optical power.

4. The zoom projection optical system according to claim 1, wherein: The second lens group includes a fourth lens, and the fourth lens has a positive optical power; the third lens group includes a fifth lens, and the fifth lens has a positive optical power; the fourth lens group includes an aperture, a sixth lens, a seventh lens, an eighth lens, a ninth lens, a tenth lens, an eleventh lens and a twelfth lens arranged in sequence from the object side to the image side along the optical axis direction, the sixth lens has a positive optical power, the seventh lens has a negative optical power, the eighth lens has a positive optical power, the ninth lens has a negative optical power, the tenth lens has a positive optical power, the eleventh lens has a positive optical power, and the twelfth lens has a positive optical power.

5. The zoom projection optical system according to claim 1, wherein: The fifth lens group includes a thirteenth lens, and the thirteenth lens has positive optical power.

6. The zoom projection optical system according to claim 1, wherein: The intervals between the multiple lens groups satisfy the following relationship: 4.57 <L 12 <5.7, 16.18 <L 23 <16.18, 14.72 <L 34 <14.72, 0.1 <L 45 <8.21; The distance between the first lens group and the second lens group is L 12 , the interval between the second lens group and the third lens group is L 23 , the interval between the third lens group and the fourth lens group is L 34 , the interval between the fourth lens group and the fifth lens group is L 45 .

7. The zoom projection optical system according to claim 1, wherein: The first lens group includes a first lens, a second lens, and a third lens arranged in sequence from the object side to the image side along the optical axis; the second lens group includes a fourth lens; the third lens group includes a fifth lens; the fourth lens group includes a stop, a sixth lens, a seventh lens, an eighth lens, a ninth lens, a tenth lens, an eleventh lens, and a twelfth lens arranged in sequence from the object side to the image side along the optical axis; the fifth lens group includes a thirteenth lens; The lens power satisfies the following relationship: In the first lens group: 0.02<|φ1|<0.04, 0.01<|φ2|<0.03, 0.03<|φ3|<0.04, in the second lens group: 0.02<|φ4|<0.03, in the third lens group: 0.02<|φ5|<0.04, in the fourth lens group: 0.01<|φ 67 |<0.02, 0.03<|φ8|<0.05, 0.03<|φ 91011 |<0.05, 0.015<|φ 12 |<0.03, in the fifth lens group: 0.02<|φ 13 |<0.03; The focal power of the first lens is φ1, the focal power of the second lens is φ2, the focal power of the third lens is φ3, the focal power of the fourth lens is φ4, the focal power of the fifth lens is φ5, and the sum of the focal powers of the sixth lens and the seventh lens is φ 67 The focal power of the eighth lens is φ8, and the sum of the focal powers of the ninth lens, the tenth lens and the eleventh lens is φ 91011 ; The focal length of the twelfth lens is φ 12 , the focal length of the thirteenth lens is φ 13 .

8. The zoom projection optical system according to claim 1, wherein: The fourth lens group includes a stop, a sixth lens, a seventh lens, an eighth lens, a ninth lens, a tenth lens, an eleventh lens and a twelfth lens, which are arranged in sequence from the object side to the image side along the optical axis; The sixth lens and the seventh lens in the fourth lens group are configured as a doublet lens, and the ninth lens, the tenth lens and the eleventh lens are configured as a triplet lens.

9. The zoom projection optical system according to claim 1, wherein: The first lens group includes a first lens, a second lens, and a third lens arranged in sequence from the object side to the image side along the optical axis; the second lens group includes a fourth lens; the third lens group includes a fifth lens; the fourth lens group includes a stop, a sixth lens, a seventh lens, an eighth lens, a ninth lens, a tenth lens, an eleventh lens, and a twelfth lens arranged in sequence from the object side to the image side along the optical axis; the fifth lens group includes a thirteenth lens; The first lens is a plastic aspheric lens, the tenth lens is a glass aspheric lens, and the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, the eighth lens, the ninth lens, the eleventh lens, the twelfth lens, and the thirteenth lens are glass spherical lenses.

10. A projection device, characterized in that: Comprising the zoom projection optical system as described in any one of claims 1 to 9.

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