Linkage zoom structure, ultra-short-focus projection lens and projection equipment

Abstract

The utility model discloses a linkage zoom structure, ultra-short focus projection lens and projection equipment, relates to the projection equipment technical field, the linkage zoom structure comprises a fixed cylinder, a first lens cone, a second lens cone and a first zoom ring, the fixed cylinder extends along the optical axis direction, the second lens cone extends along the first zoom ring, and the second zoom ring extends along the second lens cone. The first lens barrel is movably nested outside the fixed barrel along the direction of an optical axis, the second lens barrel is movably nested inside the fixed barrel along the direction of the optical axis, the first lens barrel and the second lens barrel are arranged at an interval along the direction of the optical axis, the first zoom ring is located between the first lens barrel and the second lens barrel, and the second zoom ring is located between the first lens barrel and the second lens barrel. And the first zoom ring is arranged on the fixed barrel and can be rotatably arranged on the fixed barrel, and the first zoom ring is in transmission connection with the first lens barrel and the second lens barrel so as to drive the first lens barrel and the second lens barrel to move synchronously when the first zoom ring rotates. According to the scheme, linkage zooming of the first lens cone and the second lens cone can be achieved by rotating the first zooming ring, the structure is simple, and operation is convenient.

Description

Technical Field

[0001] The utility model relates to the technical field of projection equipment, and in particular to a linkage zoom structure, an ultra-short-throw projection lens and a projection equipment. Background Art

[0002] Ultra-short-throw projectors can project large-size images within a shorter projection distance. When projecting images of the same size, the installation distance is shorter than that of long-throw projectors. This avoids users blocking the projection light and direct exposure of the projection light to the human eye, making interactive projection more feasible.

[0003] Due to the structural limitations of existing ultra-short focus lenses, the first lens group and the second lens group need two sets of focusing mechanisms to adjust the movement of the lens groups when zooming, and the two are independent and unrelated. If electric adjustment is required, two sets of drive systems and control systems need to be installed separately, which not only has a relatively high product cost, but also has a relatively large lens volume, which is not conducive to the miniaturization and precision of the projector. Utility Model Content

[0004] The main purpose of the utility model is to provide a linkage zoom structure, an ultra-short-throw projection lens and a projection device, aiming to solve the problem that the existing ultra-short-throw projection lens has a complex focusing mechanism, resulting in a large lens size and high cost.

[0005] In order to achieve the above-mentioned purpose, the utility model proposes a linkage zoom structure, comprising:

[0006] A fixed tube is extended along the optical axis direction;

[0007] A first lens barrel is movably embedded in the outside of the fixed barrel along the optical axis direction;

[0008] A second lens barrel is movably nested in the fixed barrel along the optical axis direction and is spaced apart from the first lens barrel in the optical axis direction;

[0009] The first zoom ring is located between the first lens barrel and the second lens barrel and can be rotatably mounted on the fixed barrel. The first zoom ring is transmission-connected to the first lens barrel and the second lens barrel so as to drive the first lens barrel and the second lens barrel to move synchronously when the first zoom ring rotates.

[0010] In one embodiment, the first zoom ring is provided with two first guide grooves spaced apart from each other, and the extending direction of the first guide grooves intersects with the optical axis;

[0011] The outer surfaces of the first lens barrel and the second lens barrel are both protrudingly provided with first guide pillars, and the two first guide pillars extend into the two first guide grooves respectively and abut against the groove walls of the two first guide grooves in the width direction, so that when the first zoom ring rotates, the two first guide grooves guide the two first guide pillars to move synchronously.

[0012] In one embodiment, the extension directions of the two first guide grooves are arranged at an angle.

[0013] In one embodiment, the fixing tube is provided with an avoidance groove corresponding to each of the first guide pillars, and the avoidance groove is used for allowing the corresponding first guide pillar to movably pass through.

[0014] The utility model also provides an ultra-short-throw projection lens, comprising:

[0015] case;

[0016] A linkage zoom structure, the linkage zoom structure comprising:

[0017] A fixed tube is extended along the optical axis direction;

[0018] A first lens barrel is movably embedded in the outside of the fixed barrel along the optical axis direction;

[0019] A second lens barrel is movably nested in the fixed barrel along the optical axis direction and is spaced apart from the first lens barrel in the optical axis direction;

[0020] a first zoom ring, located between the first lens barrel and the second lens barrel, and rotatably mounted on the fixed barrel, the first zoom ring being transmission-connected with the first lens barrel and the second lens barrel so as to drive the first lens barrel and the second lens barrel to move synchronously when the first zoom ring rotates;

[0021] The fixed barrel of the linkage zoom structure is fixedly arranged in the housing, and the first barrel of the linkage zoom structure comprises a first barrel body with a cut-circle cross section;

[0022] A first lens group is disposed in the first barrel, wherein the lenses in the first lens group are arranged in a circular shape; and

[0023] A second lens group is disposed in the second lens barrel and is used to cooperate with the first lens group for zooming;

[0024] The reflecting lens is arranged in the housing and is located at a side of the first lens barrel away from the second lens barrel.

[0025] In one embodiment, the first lens barrel further includes a second barrel body with a ring-shaped cross section, and the second barrel body is disposed on a side of the first barrel body close to the second lens barrel to be movably fitted on the fixed barrel.

[0026] In one embodiment, the ultra short throw projection lens further includes:

[0027] A third lens barrel is movably disposed inside the fixed barrel along the optical axis direction, and the third lens barrel is located on a side of the second lens barrel away from the first lens barrel;

[0028] The third lens group is disposed in the third lens barrel to cooperate with the first lens group and the second lens group to change the focal length of the ultra-short-throw projection lens during the movement of the third lens barrel.

[0029] In one embodiment, the ultra-short-throw projection lens further comprises a second zoom ring rotatably mounted in the fixed tube, the second zoom ring is provided with a second guide groove, and an extending direction of the second guide groove intersects with the optical axis;

[0030] A second guide post is protruded from the outer surface of the third lens barrel. The second guide post extends into the second guide groove and abuts against the groove wall of the second guide groove in the width direction, so that when the second zoom ring rotates, the second guide groove guides the second guide post to move.

[0031] In one embodiment, the ultra short-throw projection lens further includes a first motor and a second motor spaced apart inside the housing, a driving shaft of the first motor is connected to the first zoom ring, and a driving shaft of the second motor is connected to the second zoom ring.

[0032] The utility model further provides a projection device, comprising the above-mentioned ultra-short-throw projection lens, wherein the ultra-short-throw projection lens comprises:

[0033] case;

[0034] A linkage zoom structure, the linkage zoom structure comprising:

[0035] A fixed tube is extended along the optical axis direction;

[0036] A first lens barrel is movably embedded in the outside of the fixed barrel along the optical axis direction;

[0037] A second lens barrel is movably nested in the fixed barrel along the optical axis direction and is spaced apart from the first lens barrel in the optical axis direction;

[0038] a first zoom ring, located between the first lens barrel and the second lens barrel, and rotatably mounted on the fixed barrel, the first zoom ring being transmission-connected with the first lens barrel and the second lens barrel so as to drive the first lens barrel and the second lens barrel to move synchronously when the first zoom ring rotates;

[0039] The fixed barrel of the linkage zoom structure is fixedly arranged in the housing, and the first barrel of the linkage zoom structure comprises a first barrel body with a cut-circle cross section;

[0040] A first lens group is disposed in the first barrel, wherein the lenses in the first lens group are arranged in a circular shape; and

[0041] A second lens group is disposed in the second lens barrel and is used to cooperate with the first lens group for zooming;

[0042] The reflecting lens is arranged in the housing and is located at a side of the first lens barrel away from the second lens barrel.

[0043] The technical solution of the utility model is to arrange a first zoom ring between the first lens barrel and the second lens barrel which are nested, and the first zoom ring is respectively connected to the first lens barrel and the second lens barrel in transmission, so that when the first zoom ring rotates, the first lens barrel and the second lens barrel are driven to move synchronously. In this way, the linkage zoom of the first lens barrel and the second lens barrel can be achieved by rotating the first zoom ring. The structure is simple and easy to operate. The first lens barrel and the second lens barrel are nested to facilitate the assembly of the two lens barrels. In addition, the structure can still achieve a good linkage adjustment effect when facing a special-shaped lens barrel, and has strong applicability to meet the zoom requirements of the entire projection lens. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] 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.

[0045] Figure 1 A schematic structural diagram of an embodiment of an ultra-short-throw projection lens provided by the utility model;

[0046] Figure 2 for Figure 1 Structural diagram of the central linkage zoom structure;

[0047] Figure 3 for Figure 1 A structural diagram of the central linkage zoom structure from another perspective;

[0048] Figure 4 for Figure 1 Schematic diagram of the structure of the third lens group, the third lens barrel and the second zoom ring.

[0049] Description of Figure Numbers:

[0050] 1000, ultra-short-throw projection lens; 1, housing; 2, linked zoom structure; 21, fixed barrel; 22, first lens barrel; 221, first guide post; 222, first barrel body; 223, second barrel body; 23, second lens barrel; 24, first zoom ring; 241, first guide groove; 3, first lens group; 4, second lens group; 5, reflecting lens; 6, third lens barrel; 61, second guide post; 7, third lens group; 8, second zoom ring; 81, second guide groove.

[0051] 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

[0052] 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.

[0053] 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.

[0054] 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.

[0055] Ultra-short-throw projectors can project large-size images within a shorter projection distance. When projecting images of the same size, the installation distance is shorter than that of long-throw projectors. This avoids users blocking the projection light and direct exposure of the projection light to the human eye, making interactive projection more feasible.

[0056] Due to the structural limitations of existing ultra-short focus lenses, the first lens group and the second lens group need two sets of focusing mechanisms to adjust the movement of the lens groups when zooming, and the two are independent and unrelated. If electric adjustment is required, two sets of drive systems and control systems need to be installed separately, which not only has a relatively high product cost, but also has a relatively large lens volume, which is not conducive to the miniaturization and precision of the projector.

[0057] The main purpose of the utility model is to provide a linkage zoom structure, an ultra-short-throw projection lens and a projection device, aiming to solve the problem that the existing ultra-short-throw projection lens has a complex focusing mechanism, resulting in a large lens size and high cost.

[0058] See also Figures 1 to 3 To achieve the above-mentioned purpose, the utility model proposes a linkage zoom structure 2, comprising a fixed barrel 21, a first lens barrel 22, a second lens barrel 23 and a first zoom ring 24, wherein the fixed barrel 21 is extended along the optical axis direction, the first lens barrel 22 is movably nested in the outside of the fixed barrel 21 along the optical axis direction, the second lens barrel 23 is movably nested in the inside of the fixed barrel 21 along the optical axis direction, and is spaced apart from the first lens barrel 22 in the optical axis direction, the first zoom ring 24 is located between the first lens barrel 22 and the second lens barrel 23, and can be rotatably mounted on the fixed barrel 21, the first zoom ring 24 is transmission-connected with the first lens barrel 22 and the second lens barrel 23, so that when the first zoom ring 24 rotates, the first lens barrel 22 and the second lens barrel 23 are driven to move synchronously.

[0059] The technical solution of the utility model is to arrange a first zoom ring 24 between the first lens barrel 22 and the second lens barrel 23 which are nested, and the first zoom ring 24 is respectively connected to the first lens barrel 22 and the second lens barrel 23 in transmission, so that when the first zoom ring 24 rotates, the first lens barrel 22 and the second lens barrel 23 are driven to move synchronously. In this way, the linkage zoom of the first lens barrel 22 and the second lens barrel 23 can be achieved by rotating the first zoom ring 24, the structure is simple, and the operation is convenient. By nesting the first lens barrel 22 and the second lens barrel 23, it is convenient to assemble the two lens barrels, and the structure can still achieve a good linkage adjustment effect when facing a special-shaped lens barrel, and the applicability is strong to meet the zoom requirements of the entire projection lens.

[0060] It should be noted that the present solution does not limit the specific position of the first zoom ring 24. It can be rotatably installed on the outer wall of the fixed tube 21 to facilitate subsequent assembly, or it can be rotatably installed on the inner wall of the fixed tube 21 to reduce the radial size of the structure. The present solution preferably adopts the first embodiment.

[0061] It can be understood that the first lens barrel 22 and the second lens barrel 23 only have an axial movement stroke and are completely matched in the radial direction. The first zoom ring 24 is limited in both the axial and radial directions and cannot move, and can only rotate around the optical axis.

[0062] In an embodiment provided by the present utility model, please refer to Figures 2 to 3 The first zoom ring 24 is provided with two first guide grooves 241 spaced apart from each other, and the extending direction of the first guide grooves 241 intersects with the optical axis; the outer surfaces of the first lens barrel 22 and the second lens barrel 23 are both convexly provided with first guide posts 221, and the two first guide posts 221 extend into the two first guide grooves 241 respectively, and abut against the groove walls of the two first guide grooves 241 in the width direction, so that when the first zoom ring 24 rotates, the two first guide grooves 241 guide the two first guide posts 221 to move synchronously. In this way, the rotation of the first zoom ring 24 drives the two first guide grooves 241 to rotate synchronously, and since the first guide posts 221 extending into the first guide grooves 241 are limited by the first lens barrel 22 or the second lens barrel 23 to have only a stroke in the direction of the optical axis, the first guide grooves 241 can guide the first guide posts 221 to move, and the overall structure is simple and the transmission stability is high.

[0063] It should be noted that the two first guide grooves 241 have the same circumferential dimensions corresponding to the first zoom ring 24. In this way, it can be ensured that when the first zoom ring 24 is rotated, the two first guide columns 221 can synchronously move from one end of the corresponding first guide groove 241 to the other end of the first guide groove 241, thereby ensuring the linkage of the zoom.

[0064] It should also be noted that the present scheme does not limit the relative position relationship of the two first guide grooves 241, which can be spaced apart in the optical axis direction or in the circumferential direction, and it is only necessary to ensure that the corresponding first guide column 221 can extend into the first guide groove 241; the present scheme also does not limit the inclination angle of the two first guide grooves 241. In one embodiment, the extension directions of the two first guide grooves 241 are set at an angle, so that during the zooming process, the distance between the first lens group 3 and the second lens group 4 can be adjusted. In another embodiment, the extension directions of the two first guide grooves 241 are the same, so that the distance between the first lens group 3 and the second lens group 4 can be kept constant to cooperate with the zooming of other lens groups. The present scheme preferably adopts the first embodiment.

[0065] Further, in order to ensure that the first guide column 221 can cooperate with the first guide groove 241, the fixed tube 21 is provided with a avoidance groove corresponding to each of the first guide columns 221, and the avoidance groove is used for the corresponding first guide column 221 to be movably penetrated. In this way, the avoidance groove can further limit the movement of the first lens barrel 22 or the second lens barrel 23 in the optical axis direction, thereby improving the stability of the overall structure. It is understandable that when the first zoom ring 24 is arranged on the outer wall of the fixed tube 21, the avoidance groove is arranged corresponding to the first guide column 221 on the first lens barrel 22, and when the first zoom ring 24 is arranged on the inner wall of the fixed tube 21, the avoidance groove is arranged corresponding to the first guide column 221 on the second lens barrel 23.

[0066] Please refer to Figure 1 The utility model also proposes an ultra-short-focus projection lens 1000, comprising a housing 1, a linkage zoom structure 2, a first lens group 3, a second lens group 4 and a reflective lens 5. The fixed tube 21 of the linkage zoom structure 2 is fixedly arranged in the housing 1. The first lens barrel 22 of the linkage zoom structure 2 comprises a first barrel body 222 whose cross section is a cut circle. The first lens group 3 is arranged in the first barrel body 222. The lenses in the first lens group 3 are arranged in a cut circle. The second lens group 4 is arranged in the second lens barrel 23 to cooperate with the first lens group 3 for zooming. The reflective lens 5 is arranged in the housing 1 and is located on the side of the first lens barrel 22 away from the second lens barrel 23.

[0067] It is worth mentioning that, due to the characteristics of the ultra-short-throw projection lens that needs to reflect light to achieve short-distance large-screen projection, in order not to block the light from the light outlet, the lens of the first lens group 3 is usually subjected to a "D" cut process, and the lens is made into a semicircle or a cut circle, wherein the cut circle refers to a part of a circle divided by a cut line. Correspondingly, the first lens barrel 22 is also made into the same shape, so as to free up the space above the lens barrel to avoid the reflected light, which results in that the first lens barrel 22 cannot be made into a circle, and cannot share a circular focusing ring with the second lens barrel 23 whose cross section is in the shape of a circular ring. The technical solution provided by the utility model, by applying the above-mentioned linkage zoom structure 2 in the ultra-short-throw projection lens, the first lens barrel 22 and the second lens barrel 23 in the linkage zoom structure 2 are nested, and the first zoom ring 24 is arranged between the first lens barrel 22 and the lens barrel, which can well solve the problem of the zoom ring being assembled with two lens barrels of different shapes respectively, simplify the structure of the lens, and reduce the manufacturing cost of the lens in disguise.

[0068] Specifically, please refer to Figure 2The first lens barrel 22 further includes a second barrel 223 having a ring-shaped cross section. The second barrel 223 is disposed on a side of the first barrel 222 close to the second lens barrel 23, and is used to be movably matched with the fixed barrel 21. In this way, through the arrangement of the second barrel 223, the nested structure of the first lens barrel 22 and the second lens barrel 23 is realized, the overall structure is simple, and it is easy to assemble. At the same time, the coaxiality of the first lens group 3 in the first lens barrel 22 and the fixed barrel 21 is ensured, and the assembly performance is good.

[0069] For further information, please refer to Figure 1 and Figure 4 The ultra-short-focus projection lens 1000 also includes a third lens barrel 6 and a third lens group 7. The third lens barrel 6 is movably arranged inside the fixed barrel 21 along the optical axis direction. The third lens barrel 6 is located on the side of the second lens barrel 23 away from the first lens barrel 22. The third lens group 7 is arranged in the third lens barrel 6 to cooperate with the first lens group 3 and the second lens group 4 to change the focal length of the ultra-short-focus projection lens during the movement of the third lens barrel 6.

[0070] Furthermore, the ultra-short-throw projection lens 1000 further includes a second zoom ring 8 rotatably mounted in the fixed barrel 21, the second zoom ring 8 is provided with a second guide groove 81, and the extension direction of the second guide groove 81 intersects with the optical axis; the outer surface of the third lens barrel 6 is provided with a second guide post 61, the second guide post 61 extends into the second guide groove 81, and abuts against the groove wall of the second guide groove 81 in the width direction, so that when the second zoom ring 8 rotates, the second guide groove 81 guides the second guide post 61 to move. By providing the second zoom ring 8, the focusing function of the third lens group 7 is realized, the structure is simple, and the operation is convenient.

[0071] In order to realize the rotation of the first zoom ring 24 and the second zoom ring 8, in one embodiment, the ultra-short-throw projection lens 1000 further includes a first motor and a second motor arranged at intervals inside the housing 1, the driving shaft of the first motor is connected to the first zoom ring 24, and the driving shaft of the second motor is connected to the second zoom ring 8. It can be understood that the first motor and the second motor are respectively connected to the first zoom ring 24 and the second zoom ring 8 through an adapter to realize the rotation control of the zoom ring. In a preferred embodiment, the first motor and the second motor are configured as stepper motors. Since the focusing process in this solution only requires the focus ring to rotate a small angle and needs to rotate back and forth, the precise control of the rotation angle can be realized by configuring a stepper motor.

[0072] The present utility model further proposes a projection device, which includes the ultra-short-throw projection lens 1000 mentioned above. Since the projection device includes the ultra-short-throw projection lens 1000, the specific structure of the ultra-short-throw projection lens 1000 refers to the above-mentioned embodiment. Since the ultra-short-throw projection lens 1000 of 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.

[0073] 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 linkage zoom structure, characterized in that: include: A fixed tube is extended along the optical axis direction; A first lens barrel is movably embedded in the outside of the fixed barrel along the optical axis direction; A second lens barrel is movably nested in the fixed barrel along the optical axis direction and is spaced apart from the first lens barrel in the optical axis direction; The first zoom ring is located between the first lens barrel and the second lens barrel and can be rotatably mounted on the fixed barrel. The first zoom ring is transmission-connected to the first lens barrel and the second lens barrel so as to drive the first lens barrel and the second lens barrel to move synchronously when the first zoom ring rotates.

2. The linkage zoom structure according to claim 1, characterized in that: The first zoom ring is provided with two first guide grooves spaced apart from each other, and the extending direction of the first guide grooves intersects with the optical axis; The outer surfaces of the first lens barrel and the second lens barrel are both protrudingly provided with first guide pillars, and the two first guide pillars extend into the two first guide grooves respectively and abut against the groove walls of the two first guide grooves in the width direction, so that when the first zoom ring rotates, the two first guide grooves guide the two first guide pillars to move synchronously.

3. The linkage zoom structure according to claim 2, characterized in that: The extension directions of the two first guide grooves are arranged at an angle.

4. The linkage zoom structure according to claim 2, characterized in that: The fixing tube is provided with an avoidance groove corresponding to each of the first guide pillars, and the avoidance groove is used for allowing the corresponding first guide pillar to movably pass through.

5. An ultra-short-throw projection lens, characterized in that: include: case; The linkage zoom structure according to any one of claims 1 to 4, wherein the fixed barrel of the linkage zoom structure is fixedly arranged in the housing, and the first barrel of the linkage zoom structure comprises a first barrel body with a cut-circle cross section; A first lens group is disposed in the first barrel, wherein the lenses in the first lens group are arranged in a circular shape; and A second lens group is disposed in the second lens barrel and is used to cooperate with the first lens group for zooming; The reflecting lens is arranged in the housing and is located at a side of the first lens barrel away from the second lens barrel.

6. The ultra-short-throw projection lens according to claim 5, wherein: The first lens barrel further comprises a second barrel body with a ring-shaped cross section, and the second barrel body is arranged on a side of the first barrel body close to the second lens barrel, and is used for movably fitting on the fixed barrel.

7. The ultra-short-throw projection lens according to claim 5, wherein: The ultra short throw projection lens further comprises: A third lens barrel is movably disposed inside the fixed barrel along the optical axis direction, and the third lens barrel is located on a side of the second lens barrel away from the first lens barrel; The third lens group is disposed in the third lens barrel to cooperate with the first lens group and the second lens group to change the focal length of the ultra-short-throw projection lens during the movement of the third lens barrel.

8. The ultra-short-throw projection lens according to claim 7, wherein: The ultra-short-throw projection lens further comprises a second zoom ring rotatably mounted in the fixed tube, the second zoom ring is provided with a second guide groove, and the extension direction of the second guide groove intersects with the optical axis; A second guide post is protruding from the outer surface of the third lens barrel. The second guide post extends into the second guide groove and abuts against the groove wall of the second guide groove in the width direction, so that when the second zoom ring rotates, the second guide groove guides the second guide post to move.

9. The ultra-short-throw projection lens according to claim 8, wherein: The ultra-short-throw projection lens further includes a first motor and a second motor which are spaced apart inside the housing, wherein a driving shaft of the first motor is connected to the first zoom ring, and a driving shaft of the second motor is connected to the second zoom ring.

10. A projection device, characterized in that: It comprises the ultra short-throw projection lens as claimed in any one of claims 5 to 9.

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