Projection system

Abstract

The invention relates to the technical field of projection, in particular to a projection system, and part of components in a lens or tilting of the lens is adjustable. According to the projection system provided by the invention, the lens can be tilted and adjusted during side projection so as to improve a projection picture during side projection, so that the projection picture achieves a relatively good analysis effect, and clear imaging at a large-range side projection angle can be realized.

Description

Technical Field

[0001] The present invention relates to the field of projection technology, and in particular to a projection system. Background Art

[0002] The projection system mainly includes components such as light source, light valve and lens. The light valve used in LCD projection system is LCD panel, while the light valve used in DLP projection system is DMD chip. Usually, the size of LCD panel is much larger than that of DMD chip, which leads to huge difference in NA angle between LCD projection system and DLP projection system at the projection screen end when the projection screen size is the same. The existing projection system can only support a small side projection angle, and the resolution is easily reduced during side projection, which limits the application of projection system. Summary of the invention

[0003] The technical problem to be solved and the technical task proposed by the present invention are to improve the existing technology and provide a projection system to solve the problem that the side projection angle supported by the projection system in the current technology is too small and the resolution is easily reduced during side projection.

[0004] In order to solve the above technical problems, the technical solution of the present invention is:

[0005] A projection system includes a lens and a light valve, wherein some components in the lens or the entire lens are tiltable relative to an optical axis to form an adjustable component, and / or the light valve is tiltable relative to the optical axis. In the projection system described in the present invention, only some components in the lens are tiltable and adjustable, and when side projection is performed, some components in the lens can be tilted and adjusted to improve the projection picture during side projection, so that the projection picture can achieve a better resolution effect. Some components are lighter and smaller in size than the entire lens, and the force required to drive some components to tilt is smaller, that is, the driving mechanism that drives some components to tilt is smaller in size and load, which can reduce the design difficulty, does not affect the appearance of the lens, heat dissipation and other designs, and the activity space required for some components to tilt is smaller, which is conducive to improving the structural compactness of the entire projection system, reducing the gap, and improving the dustproof effect.

[0006] Furthermore, the adjustable component is a lens or lens group with the smallest absolute value of magnification in the lens. The smaller the absolute value of magnification is, the smaller the angle that the adjustable component needs to rotate and adjust during side projection is, which can reduce the activity space required for tilt adjustment, which is conducive to improving the compactness of the structure and reducing the difficulty of designing the driving mechanism.

[0007] The lens is movable and adjustable in a plane perpendicular to the optical axis, and optimization compensation is performed through axis shift adjustment to better improve the projection picture effect;

[0008] The tilt adjustment direction of the adjustable component is consistent with the tilt direction of the projection screen relative to the optical axis when the magnification of the adjustable component is positive, and is opposite to the tilt direction of the projection screen relative to the optical axis when the magnification of the adjustable component is negative, ensuring that the tilt adjustment of the adjustable component can accurately match the tilt state of the projection screen relative to the projector, and ensuring that a clear image can be obtained after the tilt adjustment.

[0009] Furthermore, the adjustable component includes a lens group or a single lens, has low driving power consumption, requires a small space, is easy to design, and avoids affecting the overall design of the projection system.

[0010] Furthermore, the rotation point of the adjustable component during tilt adjustment is on the optical axis, ensuring that the tilt adjustment of the adjustable component and the shift adjustment of the lens can be independent of each other without interfering with each other, thereby ensuring the accuracy of the adjustment and better ensuring the quality of the adjusted picture.

[0011] Further, the lens is a six-lens structure, including a front lens group, an aperture and a rear lens group arranged from the magnification side to the reduction side, the front lens group includes lens 1 and lens 2 arranged from the magnification side to the reduction side, and the rear lens group includes lens 3, lens 4, lens 5 and lens 6 arranged from the magnification side to the reduction side;

[0012] Alternatively, the lens is an eight-lens structure, including a front lens group, an aperture and a rear lens group arranged from the magnification side to the reduction side, the front lens group includes lens one, lens two and lens three arranged from the magnification side to the reduction side, and the rear lens group includes lens four, lens five, lens six, lens seven and lens eight arranged from the magnification side to the reduction side.

[0013] The lens adopts a two-group six-lens structure or a two-group eight-lens structure, with large aberration correction ability, low distortion, large relative aperture, large back intercept, and image telecentricity. It can better perform side projection and can achieve clear imaging within a large side projection angle range while ensuring that the picture has good brightness.

[0014] Furthermore, the refractive power of the rear lens group is positive, replacing the Fresnel lens, reducing the aperture of the lens and correcting the aberration. The first lens is a negative lens, which can reduce the projection ratio. When the projection distance is short, the projection image is large, and the imaging circle diameter is 0≤φ≤75.4mm.

[0015] Furthermore, in the lens of the six-lens structure, the diopter of the lenses one to six is ​​negative, positive, negative, positive, positive, positive, respectively;

[0016] In the lens with an eight-lens architecture, the refractive powers of lenses one to eight are negative, positive, positive, positive, negative, positive, positive, positive, and positive in sequence; or, the refractive powers of lenses one to eight are negative, positive, negative, negative, negative, positive, positive, and positive in sequence.

[0017] Furthermore, in the lens of the six-lens structure, the lens one, lens two, lens five and lens six are plastic aspherical lenses, and the remaining lenses are glass lenses;

[0018] In the lens with eight lens structures, lens 1 and lens 2 are plastic aspherical lenses, and the remaining lenses are glass lenses; or lens 1 and lens 3 are plastic aspherical lenses, and the remaining lenses are glass lenses. Aspherical lenses are used to correct aberrations and improve the sensitivity of components, and the processing specifications of lenses can be appropriately relaxed.

[0019] Furthermore, in the lens of the six-lens structure, the lens three and the lens four are connected to form a double cemented lens, the refractive index of the lens three is greater than the refractive index of the lens four, and the Abbe number of the lens three is less than the Abbe number of the lens four;

[0020] In the lens with eight-lens structure, lens five and lens six are connected to form a double-cemented lens, and the refractive index of lens five is greater than the refractive index of lens six.

[0021] The double-cemented lens uses a combination of high and low refractive index to effectively correct system chromatic aberration.

[0022] Further, the lens includes a lens, a lens holding member and a base member, the lens is held on the lens holding member, the lens holding member is rotatably connected to the base member through a rotating bearing part, the rotation axis of the rotating bearing part is a first direction perpendicular to the optical axis direction of the projection lens assembly, and a tilt adjustment mechanism for driving the lens holding member to tilt relative to the base member is also provided between the lens holding member and the base member, and the tilt adjustment mechanism is provided in an orientation perpendicular to the first direction. The structure is simple and compact, and the required adjustment space is small, which is conducive to reducing the volume and implementation cost of the projector, and the resolution of the projection picture is improved by the deflection of the lens when side projection is performed, which can achieve clear imaging at a wide range of side projection angles and enhance the viewing experience.

[0023] Further, the rotating bearing part includes a roller and a pin, the pin is connected to the lens holding member, the roller is connected to the assembly hole opened on the base member, and the pin is rotatably matched with the roller;

[0024] The outer wall of the roller is provided with a conical surface, and the assembly hole is provided with a conical portion that matches the conical surface. The conical surface and the conical portion cooperate to achieve automatic centering, thereby improving installation accuracy and ensuring more precise and stable deflection adjustment; or the roller cooperates with the assembly hole thread to adjust the lens retaining component along a first direction, that is, it can drive the lens to move in a direction perpendicular to the optical axis, thereby realizing eccentricity adjustment and flexibly meeting needs.

[0025] Further, the tilt adjustment mechanism includes a guide portion, a guide groove and a control member, the base member is provided with a guide groove whose length direction is along the optical axis direction, the guide portion is connected to the lens holding member, the guide portion moves along the guide groove to tilt the lens holding member, the control member is slidably connected to the base member in a direction perpendicular to the optical axis, the control member is provided with a driving groove inclined relative to the optical axis direction, the guide portion is slidably matched with the driving groove, and the control member slides relative to the base member to drive the guide portion to move along the guide groove through the driving groove;

[0026] Alternatively, the tilt adjustment mechanism includes a rotating part rotatably connected to the base component, the rotation axis of the rotating part is perpendicular to the optical axis and perpendicular to the first direction, the rotating part is provided with an eccentric portion eccentric to the rotation axis of the rotating part, the lens holding component is provided with a limiting groove cooperating with the eccentric portion, and the rotating part is rotated to drive the lens holding component to rotate around the first direction.

[0027] Furthermore, the light valve is arranged on a tilting mechanism, which includes a supporting body, a bearing member and a driving assembly. The bearing member is used to place the light valve, the bearing member is rotatably connected to the supporting body, and the driving assembly drives the bearing member to deflect relative to the supporting body. A pre-tightening mechanism is arranged between the supporting body and the bearing member.

[0028] Compared with the prior art, the present invention has the following advantages:

[0029] The projection system of the present invention can tilt and adjust some components in the lens during side projection to improve the projection picture during side projection, so that the projection picture can achieve a better resolution effect, and can achieve clear imaging at a wide range of side projection angles. It is suitable for LCD projection systems and can effectively increase the side projection angles that can be supported.

[0030] The structure is compact, and the power consumption and space required to drive some components in the lens to tilt are small, and it does not affect the design of the lens and projection system. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 is a structural schematic diagram of a projection system of the present invention;

[0032] Figure 2 is the MTF state diagram when the adjustable component is not tilted;

[0033] Figure 3 It is a schematic structural diagram of tilt adjustment of the lens 6 in the projection system of the present invention;

[0034] Figure 4 This is the MTF state diagram after the lens 6 is tilted and adjusted;

[0035] Figure 5It is a structural schematic diagram of the lens six in the projection system of the present invention performing tilt adjustment and the lens performing axis shift adjustment;

[0036] Figure 6 This is the MTF state diagram after the lens 6 is tilted and the lens is shifted;

[0037] Figure 7 is a schematic diagram of another lens structure of the present invention;

[0038] Figure 8 It is a schematic diagram of another lens structure of the present invention;

[0039] Fig. 9 is a schematic structural diagram of another projection system of the present invention;

[0040] Fig.10 is a schematic structural diagram of another projection system of the present invention;

[0041] Fig.11 is a schematic diagram of a cross-sectional structure of a lens along a first direction of the present invention;

[0042] Fig.12 is a schematic diagram of a cross-sectional structure of a lens perpendicular to a first direction of the present invention;

[0043] Fig.13 for Fig.11 A schematic diagram of the exploded structure of the projection lens assembly shown;

[0044] Fig.14 A structural schematic diagram of a rotating bearing part;

[0045] Fig.15 is another structural schematic diagram of a rotating bearing part;

[0046] Fig.16 It is another structural schematic diagram of the rotating bearing part;

[0047] Fig.17 is a schematic diagram of a cross-sectional structure of another lens along a first direction of the present invention;

[0048] Fig.18 is a schematic diagram of a cross-sectional structure of another lens of the present invention that is perpendicular to a first direction;

[0049] Fig.19 is a side cross-sectional schematic diagram of another tilt adjustment mechanism of a lens of the present invention;

[0050] Fig. 20 for Fig.19 A perspective schematic diagram of the tilt adjustment mechanism shown;

[0051] Fig.21is a schematic structural diagram of another projection system of the present invention;

[0052] Fig. 22 A schematic diagram of the structure in which the light valve is arranged on the tilting mechanism;

[0053] Fig.23 for Fig. 22 Schematic diagram of the structure on the other side.

[0054] In the figure:

[0055] Lens 1, adjustable component 10, lens 1 11, lens 2 12, lens 3 13, lens 4 14, lens 5 15, lens 6 16, lens 7 17, lens 8 18, aperture 19, light valve 2, projection screen 3; lens 101, lens holding member 102, base member 103, rotating bearing portion 104, roller 1041, pin 1042, guide portion 1051, guide groove 1052, control member 1053, driving groove 1054, limiting roller 1055, sliding groove 1056, lever 1061, motor 1062, gear portion 1063, rotating member 1071, eccentric portion 1072, limiting groove 1073; supporting body 41, bearing member 42, worm portion 43, worm wheel portion 44, motor 45, detection sensor 46, trigger portion 47. DETAILED DESCRIPTION

[0056] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0057] A projection system disclosed in an embodiment of the present invention performs correction optimization during side projection, solves the problem of resolution degradation caused by large side projection angles, achieves clear imaging in a wide range of side projection angles, and improves imaging quality.

[0058] like Figure 1As shown, a projection system mainly includes a lens 1 and a light valve 2, wherein some components in the lens 1 or the entire lens 1 can be tilted relative to the optical axis to form an adjustable component 10, and / or the light valve 2 can be tilted relative to the optical axis. Specifically, this embodiment is described by taking the light valve 2 as an LCD panel as an example, the illumination light beam emitted by the light source of the projection system is incident on the LCD panel, and is modulated by the LCD panel to become an image light beam to be emitted to the lens 1, and finally the lens 1 projects the image light beam onto the projection screen 3 to obtain a projection picture. When the projection screen 3 is tilted relative to the projector, that is, the optical axis of the image light beam emitted from the lens 1 is not perpendicular to the projection screen 3, the projection picture will be trapezoidal, and the resolution will decrease. This embodiment optimizes and improves by tilting and adjusting the adjustable component 10 in the lens 1. In the case of side projection, before the adjustable components are driven, the image plane of the light valve, the plane of the screen and the lens do not intersect in the same straight line, which may easily lead to defocus and reduced resolution, especially when the side projection angle is large, the defocus and reduced resolution are more serious. By tilting the entire lens 1 and / or tilting the light valve 2 so that the image plane of the light valve, the plane of the lens and the screen intersect in the same straight line, or by tilting and adjusting some components in the lens 1 so that the image plane of the light valve, the plane of the lens and the screen are close to intersecting in the same straight line (the intersection state of the three is within the preset error range), the defocus problem can be solved, high-resolution imaging can be obtained, and the quality of the projection picture can be effectively improved.

[0059] In one embodiment, the tilt adjustment is for some components in the lens 1 rather than the entire lens 1. When the tilt adjustment is performed for some components in the lens 1, the plane of the entire lens 1 will be deflected, so that the image plane of the light valve, the plane of the lens and the screen intersect in the same straight line, thereby obtaining a clear image. Relatively speaking, some components are lighter and smaller in size than the entire lens 1, and the force and activity space required to drive the partial components to perform tilting activities are smaller, so that the driving mechanism required to drive the partial components to perform tilting has lower power consumption and smaller volume, which is conducive to improving the compactness of the projection system, reducing the overall space occupied by the projection system, and does not affect the appearance, heat dissipation and other designs of the lens 1. The lens 1 as a whole does not need to be deflected relative to the body of the projection system, which is conducive to the design of dustproof structure and dustproof effect.

[0060] The adjustable component 10 can be a single lens or a lens group. Figure 1As shown, the lens 1 is a six-lens structure, and the lens 1 includes a front lens group, an aperture 19, and a rear lens group arranged from the magnification side to the reduction side. The front lens group includes a lens 1 11 and a lens 2 12 arranged from the magnification side to the reduction side, and the rear lens group includes a lens 3 13, a lens 4 14, a lens 5 15, and a lens 6 16 arranged from the magnification side to the reduction side. The lens 1 11 and the lens 2 12 are aspherical lenses, the lens 3 13 and the lens 4 14 are connected to form a double-cemented lens, and the lens 5 15 and the lens 6 16 are aspherical lenses. The adjustable component 10 can be a single lens from the lens 1 11 to the lens 6 16, or a front lens group or a rear lens group, which can be flexibly selected according to needs.

[0061] More specifically, the overall refractive power of the rear lens group is positive, lens one is a negative lens, and the imaging circle diameter is 0≤φ≤75.4mm. The imaging circle refers to the imaging of the entire lens. Conventional lenses for LCD panels usually use Fresnel lenses as field lenses to correct light deflection, but this results in poor projection image quality. Lens group two is used to replace the traditional Fresnel lens to improve image quality, and can reduce the lens aperture and correct aberrations. Furthermore, the refractive powers of lens one 11 to lens six 16 are negative, positive, negative, positive, positive, and positive, respectively. Among them, lens one 11 with a negative refractive power can reduce the projection ratio and achieve a large projection image when the projection distance is short.

[0062] The lens 1 11 and the lens 2 12 are plastic aspheric lenses, which can correct high-order aberrations on the axis and compress the lens aperture. The lens 1 11 is a meniscus lens convex to the reduction side, and the surface of the lens 1 11 on the magnification side and the surface on the reduction side are both even-order aspheric surfaces. The lens 2 12 is a meniscus lens convex to the magnification side, and the surface of the lens 2 12 on the magnification side and the surface on the reduction side are both even-order aspheric surfaces. By reasonably optimizing the aspheric coefficients on both sides of the lens 1 11 and the lens 2 12, the system astigmatism and coma are effectively corrected;

[0063] Furthermore, the lens 5 15 and the lens 6 16, which are plastic aspheric lenses, can compress the lens aperture, correct the off-axis aberration and distortion, and adopt the structure of multiple aspheric lenses, which can simplify the number of lenses of the lens and improve the optical performance parameters. The entire lens 1 includes four plastic lenses, and only the lens 3 13 and the lens 4 14 are glass lenses. On the basis of ensuring the correction of aberrations, the sensitivity of the lens can be improved, the processing specifications of the lens can be appropriately relaxed, and the cost can be reduced. In addition, the lens 3 13 and the lens 4 14 are connected to form a double-cemented lens, the refractive index of the lens 3 13 is greater than the refractive index of the lens 4 14, and the Abbe number of the lens 3 13 is less than the Abbe number of the lens 4 14. Specifically, the lens 3 13 is a double concave lens, and the lens 4 14 is a double convex lens. The two are connected to form a double-cemented structure with negative and positive refractive powers and high and low refractive indices, which can better correct the chromatic aberration of the picture and ensure that the entire optical system has a small chromatic aberration.

[0064] The focal length of the lens 1 of the above-mentioned architecture is 60mm≤EFL≤80mm, the ratio of the lens back focal length to the effective focal length is BFL / EFL≥1.0, the aperture number is 1.7≤FNO≤3.0, the total length of the lens is TTL≤200mm, the system field of view angle is ≧56.1°, the ratio of the lens projection distance to the screen width is: 1.1≤TR≤1.3, and the ratio of the total length of the lens to the effective focal length is TTL / EFL≥2.86. Among them, the total length of the lens TTL can be defined as the distance from the vertex of the magnified side surface of the lens 11 to the image plane where the light valve is located. The above-mentioned lens can effectively improve the chromatic aberration of the system and suppress the occurrence of system distortion. The number of optical lenses used is small, the structure is simplified, the field of view angle is large, the aperture diameter is large, the distortion is low, the cost is low, and the high performance MTF value can be ensured at high temperature.

[0065] When tilted projection occurs (side projection tilted left and right and pitch projection tilted up and down), the tilt angle that the adjustable component 10 needs to adjust is related to the tilt angle of the projection screen 3 relative to the projector and the magnification of the adjustable component 10. The size difference between the projection screen 3 and the light valve 2 is large, and the smaller the absolute value of the magnification of the adjustable component 10 is, the smaller the tilt angle that needs to be tilted is. For the projection system, it is preferred to select the lens or lens group with the smallest absolute value of the magnification in the lens 1 as the adjustable component 10, so that when side projection is performed, the angle that the adjustable component 10 needs to rotate is the smallest, which can reduce the activity space required for tilt adjustment, improve the compactness of the structure, and reduce the difficulty of designing the activity mechanism that drives the adjustable component 10 to tilt.

[0066] For a single lens or a single lens group, the magnification is

[0067]

[0068] Among them, n is the refractive index on the object side, n' is the refractive index on the image side, for a lens or a lens group, both sides of it are air, then n and n' are the same, l' is the image distance, l is the object distance, for a lens or a lens group, the object distance is the distance from the image of the projection screen 3 obtained through all the lenses on the magnification side of the lens to the lens, and the image distance is the distance from the image of the light valve 2 obtained through all the lenses on the reduction side of the lens to the lens. Specifically, taking lens six 16 as an example, the distance from the image of the projection screen 3 after passing through lenses one 11 to five 15 to lens six 16 is the object distance, and the distance from the light valve 2 to lens six 16 is the image distance.

[0069] When the magnification of the adjustable component 10 is positive, the tilt adjustment direction of the adjustable component 10 is consistent with the tilt direction of the projection screen 3 relative to the optical axis. Figure 3 As shown, the tilt direction of the projection screen 3 relative to the optical axis is clockwise, and the tilt adjustment direction of the lens 6 16 relative to the optical axis is also clockwise. When the adjustable component 10 is not tilted for compensation, the MTF is as follows: Figure 2 As shown, after tilting and adjusting the lens 616 to perform compensation, the MTF is as follows: Figure 4 As shown, it can be seen that the MTF performance can be effectively improved. If the magnification of the adjustable component 10 is negative, the tilt adjustment direction of the adjustable component 10 is opposite to the tilt direction of the projection screen 3 relative to the optical axis. For the case where some components in the lens 1 are adjustable relative to the optical axis to form the adjustable component 10, the magnification of the adjustable component 10 may be positive or negative, so there is a situation where the tilt adjustment direction of the adjustable component 10 is consistent with or opposite to the tilt direction of the projection screen 3 relative to the optical axis. When the entire lens 1 is tilted relative to the optical axis to form the adjustable component 10, the tilt adjustment direction of the entire lens 1 is opposite to the tilt direction of the projection screen 3 relative to the optical axis.

[0070] Furthermore, the projection screen 3 has various conditions when tilted relative to the optical axis, which may be tilted up and down or tilted left and right, that is, there are various conditions for side projection. In order to flexibly adapt to various side projection conditions, the adjustable component 10 in the lens 1 also needs to be able to tilt up and down and left and right relative to the optical axis relative to the lens 1 as a whole. Specifically, a bracket component that can rotate along the circumference of the optical axis relative to the main barrel is provided on the main barrel of the lens 1, and the adjustable component 10 is rotatably connected to the bracket component. The rotation axis of the adjustable component 10 relative to the bracket component is perpendicular to the optical axis and passes through the optical axis, that is, the rotation point position of the adjustable component 10 when the tilt is adjusted is on the optical axis, so that the adjustable component 10 can be tilted in any direction relative to the optical axis through the tilting activity of the adjustable component 10 relative to the bracket component and the rotation activity of the bracket component relative to the main barrel. The tilting of the optical axis can be flexibly adapted to the tilt of the projection screen 3 relative to the optical axis.

[0071] Furthermore, the entire lens 1 is shifted to perform compensation optimization during side projection, that is, the entire lens 1 is movable and adjustable in a plane perpendicular to the optical axis to have a shift function, so as to further optimize and compensate by means of shift adjustment. Furthermore, when the adjustable component 10 in the lens 1 is tilted, or when the adjustable component 10 in the lens 1 is tilted and the adjustable component 10 is shifted, the entire lens 1 is also fine-focused along the optical axis, so that the image beam can be more accurately imaged on the projection screen, thereby better improving the projection imaging quality.

[0072] When the above-mentioned projection system is used for side projection, the tilt angle of the projection screen 3 relative to the optical axis is first detected. A camera may be provided on the projector to capture the image projected on the projection screen 3 by the camera, and the tilt angle of the projection screen 3 relative to the optical axis is obtained by image recognition calculation, or a multi-point TOF sensor is used to detect the projection screen 3 to obtain the tilt angle of the projection screen 3 relative to the optical axis.

[0073] Then, the control parameters of the adjustable component 10 in the lens 1 are obtained by obtaining the inclination angle of the projection screen 3 relative to the optical axis. Specifically, according to the detected inclination angle detection value of the projection screen relative to the optical axis, the control parameters matching the inclination angle detection value are retrieved in the adjustment parameter database, and then the adjustable component in the lens is tilted and adjusted according to the control parameters, wherein the adjustment parameter database stores the inclination angle of the projection screen relative to the optical axis and the control parameters matching therewith. More specifically, the control parameters in the adjustment parameter database are first calculated to obtain a theoretical adjustment amount matching the inclination angle of the projection screen relative to the optical axis, and the theoretical adjustment amount can be obtained by the angular magnification of the adjustable component, and the angular magnification is the inverse of the magnification β of the adjustable component 10. Then, the projector is calibrated to revise the theoretical adjustment amount to obtain the control parameters.

[0074] This method makes the control of adjustable components more efficient, improves response speed, and enhances user experience. In addition, the control parameters revised from the theoretical adjustment amount are obtained by calibrating the actual projector. Compared with the theoretical adjustment amount, the revised control parameters are more precise because the phase difference balance factor is taken into account to ensure the best projection picture.

[0075] It is also possible to first tilt the adjustable component to near the target value, then scan and acquire the projected screen image, acquire the clarity of the screen image, and tilt and adjust the adjustable component until the clarity of the screen image meets the preset requirements.

[0076] Furthermore, when the magnification of the adjustable component 10 is positive, that is, for the adjustable component 10, its object and phase are on the same side of the adjustable component 10, so that the tilt adjustment direction of the adjustable component 10 is consistent with the tilt direction of the projection screen 3 relative to the optical axis; and when the magnification of the adjustable component 10 in the lens 1 is negative, the tilt adjustment direction of the adjustable component 10 is opposite to the tilt direction of the projection screen 3 relative to the optical axis.

[0077] In some scenarios, when the adjustable component 10 in the lens 1 is tilted and adjusted relative to the optical axis, the lens 1 as a whole is also shifted and adjusted to further optimize and compensate, such as Figure 5 As shown, while the lens 6 16 is tilted relative to the optical axis, the entire lens 1 is also shifted to compensate. The MTF after compensation is as follows: Figure 6 As shown, it can better improve the MTF performance and improve the projection image quality.

[0078] In addition to the aforementioned lens structure, the lens 1 can also be Figure 7 As shown, the lens 1 also adopts a structure of two lens groups and six lenses. The front lens group includes a lens 1 11 with positive refractive power and a lens 2 12 with positive refractive power arranged from the magnification side to the reduction side, and the rear lens group includes a lens 3 13 with negative refractive power, a lens 4 14 with positive refractive power, a lens 5 15 with positive refractive power and a lens 6 16 with positive refractive power arranged from the magnification side to the reduction side.

[0079] Specifically, the lens 1 11 is a positive meniscus lens convex to the reduction side, the lens 2 12 is a positive meniscus lens convex to the magnification side, and the lens 1 11 and the lens 2 12 are both plastic aspheric lenses. The lens 3 13 and the lens 4 14 are independent single lenses, specifically, the lens 3 13 is a negative glass lens with both sides convex to the reduction side, the lens 4 14 is a positive meniscus glass lens convex to the reduction side, the lens 5 15 is a double convex lens, the lens 6 16 is a positive meniscus lens convex to the magnification side, and the lens 5 15 and the lens 6 16 are plastic aspheric lenses.

[0080] You can also use Figure 8 The lens 1 shown is also a structure of two lens groups and six lenses. The front lens group includes a lens 1 11 with a negative refractive power and a lens 2 12 with a positive refractive power arranged from the magnification side to the reduction side, and the rear lens group includes a lens 3 13 with a negative refractive power, a lens 4 14 with a positive refractive power, a lens 5 15 with a positive refractive power, and a lens 6 16 with a positive refractive power arranged from the magnification side to the reduction side.

[0081] Specifically, the refractive power of the lens 11 is negative, and the surface of the lens 11 on the magnification side is a curved surface with the middle part concave toward the reduction side and the edge curved toward the reduction side. It can also be expressed as follows: the cross section of the surface of the lens 11 on the magnification side is wavy, and the surface of the lens 11 on the magnification side has an inflection point change from the middle to the edge convex toward the magnification side, and the surface of the lens 11 on the reduction side is a curved surface convex toward the magnification side. The lens 2 12 is a positive meniscus lens convex toward the magnification side, and both the lens 1 11 and the lens 2 12 are plastic aspherical lenses.

[0082] The lens three 13 is a double concave glass lens, the lens four 14 is a double convex glass lens, the lens three 13 and the lens four 14 are connected to form a double cemented lens, the lens three 13 is made of a material with a high refractive index and a low Abbe number, and the lens four 14 is made of a material with a low refractive index and a high Abbe number, which can effectively ameliorate chromatic aberration. The lens five 15 is a double convex lens, the lens six 16 is a meniscus lens with a positive refractive power convex to the magnification side, and the lens five 15 and the lens six 16 are plastic aspherical lenses.

[0083] like Fig. 9 As shown, the lens can also adopt a two-group, eight-lens architecture, specifically, including a front lens group, an aperture 19 and a rear lens group arranged from the magnification side to the reduction side, the front lens group includes lens one 11, lens two 12 and lens three 13 arranged from the magnification side to the reduction side, and the rear lens group includes lens four 14, lens five 15, lens six 16, lens seven 17 and lens eight 18 arranged from the magnification side to the reduction side.

[0084] The refractive power of lens 1 11 is negative, and the refractive power of lens 2 12 is positive, and lens 1 11 is a negative meniscus lens convex to the magnification side, and lens 2 12 is a positive meniscus lens convex to the magnification side, and the lens 1 11 and the lens 2 12 are plastic aspherical lenses, and the remaining lenses are glass lenses. The number of plastic lenses is small, which can improve the thermal defocus performance of the entire lens assembly 2. The aspherical mirror can improve the field of view of the lens system, and well correct the off-axis aberration, system distortion, astigmatism and sine difference. By reasonably optimizing the aspherical coefficient, the system astigmatism and coma are effectively corrected. Lens 1 11 and lens 2 12 use positive and negative focal lengths to achieve mutual compensation and offset when the temperature changes, reducing the impact of the temperature rise on the performance of the lens. Further, the two aspherical mirrors satisfy the relationship -1.3≤f_asp1 / f_asp2≤0.7, where f_asp1 is the focal length of lens 1 11, and f_asp2 is the focal length of lens 2 12, ensuring the optical MTF performance at different temperatures. The refractive power of lens three 13 is positive, and it is a meniscus lens convex toward the magnification side.

[0085] The refractive power of lens four 14 is positive, and it is a meniscus lens convex to the reduction side, which has a better effect on the field curvature and astigmatism of the system. The refractive power of lens five 15 is negative, and lens five 15 is specifically a biconcave lens. The refractive power of lens six 16 is positive, and it is specifically a biconvex positive lens. In addition, the lens five 15 and the lens six 16 are connected to form a double-cemented lens. The refractive index of the lens five 15 is greater than the refractive index of the lens six 16. The double-cemented lens is combined with high and low refractive indices to effectively correct chromatic aberration. The double-cemented lens adopts a negative-positive bonding structure with a refractive power, wherein the Dn / Dt of the material used for the positive lens six 16 is a negative number, and the Dn / Dt is the trend of the refractive index changing with temperature, which can perform thermal compensation on the optical system. Further, the refractive power of lens seven 17 is positive, and it is specifically a meniscus positive lens convex to the reduction side. The refractive power of lens eight 18 is positive, and it is specifically a biconvex positive lens.

[0086] In the above-mentioned lens 1, the refractive power of the rear lens group is positive, which replaces the Fresnel lens, reduces the aperture of the lens and corrects the aberration. The lens 11 is a negative lens, which can reduce the projection ratio. When the projection distance is short, the projection picture is large, and the imaging circle diameter is 0≤φ≤75.4mm. More specifically, the focal length of the front lens group is 50mm≤f1≤200mm, the focal length of the rear lens group is 50mm≤f2≤100mm, the aperture 19 is set near the focal position of the rear lens group, the focal length of the lens is 60mm≤EFL≤80mm, the ratio of the rear focal length of the lens to the effective focal length is 0.5≤BFL / EFL≤2.5, the aperture number is 2.0≤FNO≤3.0, the total length of the lens is TTL≤200mm, the system field of view angle is ≥56.1°, the ratio of the lens projection distance to the picture width is 1.1≤TR≤1.3, and the ratio of the total length of the lens to the effective focal length is 2.85≤TTL / EFL≤5.0. Lens 1 can effectively improve the chromatic aberration of the system and suppress the occurrence of system distortion. While meeting the design of 75.4mm image target surface, the number of optical lenses used is relatively small. Lens 1 has large aberration correction ability, low distortion, large relative aperture, large back intercept, image telecentricity and high imaging quality, better supports large-angle side projection, and optimizes and improves the projection image quality.

[0087] like Fig.10 Another lens 1 shown still adopts a two-group, eight-lens structure, including a front lens group, an aperture 19 and a rear lens group arranged from the magnification side to the reduction side. The front lens group includes lens one 11, lens two 12 and lens three 13 arranged from the magnification side to the reduction side, and the rear lens group two includes lens four 14, lens five 15, lens six 16, lens seven 17 and lens eight 18 arranged from the magnification side to the reduction side. The difference from the previous lens is that the refractive powers of lenses one 11 to eight 18 are negative, positive, negative, negative, negative, positive, positive, positive, respectively.

[0088] Specifically, lens one 11 is a negative meniscus lens convex to the magnifying side, lens two 12 is a positive meniscus lens convex to the magnifying side, lens three 13 is a negative meniscus lens convex to the magnifying side, lens one 11 and lens three 13 are plastic aspherical lenses, and the remaining lenses are glass lenses. The number of plastic lenses is small, which can improve the thermal defocus performance of the entire lens assembly 2. The surfaces on both sides of lens one 11 are even-order aspherical surfaces, and the surfaces on both sides of lens three 13 are even-order aspherical surfaces.

[0089] Lens four 14 is a meniscus negative lens convex to the reduction side, which is beneficial to the improvement of the field curvature and astigmatism correction of the system. Lens five 15 is a double concave negative lens, and lens six 16 is a double convex positive lens. The lens five 15 and the lens six 16 are connected to form a double cemented lens, which is combined into a double cemented lens with high and low refractive indices to effectively correct chromatic aberration. Lens seven 17 is a meniscus positive lens convex to the reduction side, and lens eight 18 is a double convex positive lens.

[0090] Some components in the lens 1 can be tilted and adjusted relative to the optical axis to form an adjustable component. The specific structure is as follows Figures 11 to 13 As shown, the lens 1 includes a lens 101, a lens holding component 102 and a base component 103. The lens 101 is held on the lens holding component 102. The lens holding component 102 is rotatably connected to the base component 103 via a rotating bearing portion 104. The rotation axis of the rotating bearing portion 104 is a first direction perpendicular to the optical axis direction of the projection lens assembly. A tilt adjustment mechanism for driving the lens holding component 102 to tilt relative to the base component 103 is also provided between the lens holding component 102 and the base component 103. The tilt adjustment mechanism is provided in a direction perpendicular to the first direction.

[0091] In the present embodiment, the lens 101 mounted on the lens holding component 102 is only a single lens, and the lens 101 is a part of the lens structure of the entire optical lens. The base component 103 is the lens barrel of the entire optical lens, and the remaining lenses in the optical lens are mounted and connected to the base component 103, so that a part of the lenses in the optical lens are fixed and non-adjustable relative to the optical axis, while the lens 101 mounted on the lens holding component 102 is adjustable relative to the optical axis, so that the projected light can be deflected by tilting the lens 101 held on the lens holding component 102 relative to the optical axis, thereby realizing the movement of the projection picture in a side projection manner. Compared with moving the projection picture in an axis-shift manner, the angle of deflection required for the lens 101 in side projection is smaller, so that the required adjustment space is smaller, which is beneficial to reducing the size and implementation cost of the projector. Of course, the lens 101 installed on the lens holding component 102 can also be a plurality of lenses, specifically a lens group in an optical lens, which can also be tilted and adjusted relative to the optical axis to achieve side projection. When side projection is performed, the resolution of the projected image can be improved, and clear imaging can be achieved in a wide range of side projection angles, thereby enhancing the viewing experience.

[0092] More specifically, the lens holding member 102 is an annular support member, the center of which is a through hole for light to pass through, and the lens 101 is placed on the lens holding member 102 and fixed on the lens holding member 102 by a pressure ring, which has a simple structure and is easy to assemble and disassemble for maintenance. In this embodiment, the base member 103 is the lens barrel of the entire optical lens, so that the base member 103 is a cylindrical member as a whole, and the annular lens holding member 102 is inserted into the inside of the base member 103. The two sides of the lens holding member 102 in the diameter direction are respectively connected to the base member 103 by a rotating bearing part 104, and the rotation stability is good. The rotation axis of the rotating bearing part 104 passes through the optical axis, which ensures that the lens 101 will only tilt relative to the optical axis when the tilt adjustment is performed, avoiding the eccentricity of the lens 101 relative to the optical axis (that is, the lens 101 has a lateral displacement relative to the optical axis in a direction perpendicular to the optical axis), improving the accuracy of the tilt adjustment, and avoiding the occurrence of eccentricity and affecting the projection adjustment effect.

[0093] Further, such as Figures 14 to 16 As shown, the rotating bearing part 104 includes a roller 1041 and a pin 1042. The pin 1042 is specifically a screw connected to the side of the outer periphery of the lens holding member 102. The roller 1041 is connected to the assembly hole opened on the wall surface of the base member 103. The pin 1042 is rotatably connected with the roller 1041. The roller 1041 is cylindrical. The pin 1042 passes through the through hole of the roller 1041 and is screwed to the lens holding member 102. The structure is simple and the assembly is convenient. Fig.14As shown, the outer circumference of the roller 1041 is a cylindrical surface, and the assembly hole on the base member 103 is a matching cylindrical hole, which has a simple structure and is easy to assemble. Fig.15 As shown, the outer peripheral wall of the roller 1041 is provided with a conical surface, and correspondingly, the assembly hole is provided with a conical portion that matches the conical surface, so that when the roller 1041 is installed in the assembly hole, the conical surface and the conical portion cooperate to perform automatic centering, thereby improving the installation accuracy and stability, and ensuring that the rotation axis formed by the rotating bearing part 104 is accurately perpendicular to the optical axis and passes through the optical axis. Fig.16 As shown, the outer wall surface of the roller 1041 is provided with a thread, and the roller 1041 is threadedly connected with the assembly hole, and the through hole of the roller 1041 is provided with a step portion to limit the pin 1042 along the axial direction, and the roller 1041 is screwed to drive the pin 1042 to move along the first direction, that is, the lens holding component 102 can be adjusted along the first direction, and the rotating bearing portion 104 is used as a rotating connection portion for supporting the lens holding component 102, so that the lens holding component 102 has a rotational freedom to rotate along the first direction relative to the base component 103, and the rotating bearing portion 104 can also be used to move the lens holding component 102 along the first direction, so as to facilitate the precise assembly of the lens, ensure that the lens 101 on the lens holding component 102 can be coaxial with the optical axis, avoid the condition of eccentricity, and ensure the accuracy of tilt adjustment during side projection.

[0094] like Fig.12 As shown, the tilt adjustment mechanism includes a guide portion 1051 and a guide groove 1052. The guide groove 1052 with its length direction along the optical axis is provided on the wall surface of the base member 103. Since the tilt adjustment mechanism is provided in an orientation perpendicular to the first direction, that is, the distribution orientation of the guide groove 1052 and the rotating bearing portion 104 in the circumferential direction of the base member 103 differs by 90°, the guide portion 1051 is connected and provided on the lens holding member 102, and correspondingly, the distribution orientation of the guide portion 1051 and the rotating bearing portion 104 in the circumferential direction of the lens holding member 102 differs by 90°. The guide portion 1051 moves along the guide groove 1052, thereby driving the lens holding member 102 to rotate relative to the base member 103 along the rotation axis of the rotating bearing portion 104, that is, driving the lens 101 provided on the lens holding member 102 to tilt relative to the optical axis. In this embodiment, only one set of tilt adjustment mechanisms is provided, that is, only one guide groove 1052 is provided on the base member 103 , and the single-sided driving guide portion 1051 of the lens holding member 102 moves along the guide groove 1052 to drive the lens holding member 102 to deflect.

[0095] Furthermore, in order to improve the convenience and stability of driving the lens holding member 102 to deflect, the tilt adjustment mechanism is further provided with a control member 1053, which is a cylindrical member, and is sleeved on the periphery of the base member 103. The control member 1053 is rotatably connected to the base member 103 along the circumference of the base member 103, that is, the control member 1053 can slide relative to the base member 103 in a direction perpendicular to the optical axis. The control member 1053 is provided with a driving groove 1054, and the driving groove 1054 is inclined relative to the optical axis direction. The guide portion 1051 is slidably matched with the driving groove 1054, so that when the control member 1053 slides along the circumference of the base member 103 relative to the base member 103, the driving groove 1054 drives the guide portion 1051 to move along the guide groove 1052, that is, when the control member 1053 rotates relative to the base member 103, it drives the lens holding member 102 to tilt.

[0096] In order to ensure that the control member 1053 rotates accurately and stably along the circumferential direction of the base member 103, three limiting rollers 1055 are arranged on the outer wall of the base member 103 at intervals along the circumference of the base member 103, and the control member 1053 is provided with a sliding groove 1056 whose length direction is along the circumference of the base member 103. Correspondingly, the sliding groove 1056 is distributed with three intervals along the circumference to slide with one limiting roller 1055 respectively, and the two side edges of the sliding groove 1056 are in contact with the limiting roller 1055 to achieve limitation in the axial direction of the base member 103, thereby ensuring that the control member 1053 rotates accurately and stably along the circumferential direction of the base member 103, and further ensuring that the control member 1053 can accurately and stably drive the guide part 1051 to move along the guide groove 1052 to achieve the tilt adjustment of the lens holding member 102. The angle at which the lens 101 on the lens holding component 102 can be tilted relative to the optical axis is determined by the stroke length of the guide groove 1052, and the tilting angle of the lens 101 is related to the offset angle of the center of the projection image during side projection.

[0097] In this embodiment, the lens 101 closest to the reduction side is placed on the lens holding member 102 to form a tiltable and adjustable component. Assuming that the projector supports a projection screen center offset of ±30°, the angle at which the lens 101 needs to be tilted relative to the optical axis is converted to ±1.8°, and then the travel of the guide portion 1051 along the guide groove 1052 is calculated to be 1.82 mm, so that the overall travel length of the guide groove 1052 is at least 3.64 mm. In order to meet the requirements of the optical side projection screen, the travel length is set to 4.0 mm, and the circumferential angle range covered by the driving groove 1054 on the control member 1053 is set to 60°, that is, the control Component 1053 rotates 60° relative to the base component 103 to drive the lens 101 to rotate from -1.8° to +1.8° relative to the optical axis, and the slope of the driving groove 1054 can be calculated to be 0.0175. The slope of the driving groove 1054 specifically refers to the slope of the cross section of the driving groove 1054 relative to the vertical optical axis when the cylindrical control component 1053 is unfolded into a plane. The driving groove 1054 satisfies the relationship k=180*sinθ / (α*π), wherein k is the slope of the driving groove 1054, θ is the preset maximum tilt angle of the lens holding component 102, and α is the angle range covered by the driving groove 1054 in the rotation circumferential direction.

[0098] Furthermore, in this embodiment, if Fig.12 and Fig.13 As shown, the control member 1053 is driven by a driving mechanism. Specifically, the driving mechanism is a lever 1061 connected to the control member 1053. The lever 1061 is threadedly connected to the control member 1053, and is convenient and simple to assemble and disassemble. By manually pushing the lever 1061 to rotate the control member 1053 relative to the base member 103, the lens 101 can be driven to tilt and adjust relative to the optical axis. The structure is simple and easy to operate.

[0099] Since the lens holding member 102 is a movable part relative to the base member 103, there is a risk of dust ingress, and a dustproof member may be provided between the lens holding member 102 and the base member 103. The dustproof member may be foam or Mylar sheet.

[0100] like Fig.17 and Fig.18As shown, the difference from the previous embodiment is that the lens 101 and the lens holding member 102 are combined to form the entire lens, so that the lens holding member 102 is the lens barrel of the entire optical lens, and the base member 103 is a flange member for carrying and connecting the entire optical lens. In this embodiment, the entire optical lens is tilted and adjusted to perform side projection to move the projection picture. When performing side projection, the entire optical lens is tilted and adjusted to make the extended planes of the image plane of the light valve, the screen and the plane of the optical lens intersect in a straight line, thereby obtaining a clear projection picture.

[0101] Furthermore, the driving mechanism adopted in this embodiment includes a motor 1062, which is fixedly arranged on the base component 103. The control component 1053 is provided with a gear portion 1063, and a gear that is transmission-connected to the gear portion 1063 is provided on the output shaft of the motor 1062, so that when the motor 1062 is working, it drives the control component 1053 to rotate relative to the base component 103, thereby driving the entire optical lens to tilt relative to the optical axis.

[0102] In this embodiment, assuming that the projector supports a projection screen center offset of ±40°, the angle at which the optical lens needs to be tilted relative to the optical axis is converted to ±1.65°, and then the travel of the guide portion 1051 along the guide groove 1052 is calculated to be 1.72 mm, so that the overall travel length of the guide groove 1052 is at least 3.43 mm. To meet the requirements of the optical side projection screen, the travel length is set to 3.5 mm, and the circumferential angle range covered by the drive groove 1054 on the control member 1053 is set to 60°, that is, the control member 1053 rotates 60° relative to the base member 103 to drive the optical lens to rotate from -1.65° to +1.65° relative to the optical axis, and then the slope of the drive groove 1054 can be calculated to be 0.0174.

[0103] Since the entire optical lens needs to be tilted, there is a risk of dust entering between the end side of the optical lens and the projector body. A dustproof rubber sleeve can be installed on the end side of the optical lens, which can elastically deform with the movement of the optical lens to ensure good sealing and dustproof effect.

[0104] like Fig.19 and Fig. 20As shown, different from the tilt adjustment mechanism used in the previous two embodiments, the tilt adjustment mechanism of this embodiment includes a rotating member 1071 rotatably connected to the base member 103, the rotation axis of the rotating member 1071 is perpendicular to the optical axis and perpendicular to the first direction, the rotating member 1071 is specifically arranged in an orientation perpendicular to the first direction, that is, the distribution orientation of the rotating member 1071 and the rotating bearing portion 104 in the circumferential direction of the base member 103 differs by 90°, the rotating member 1071 is provided with an eccentric portion 1072 eccentric to the rotation axis of the rotating member 1071, and the lens holding member 102 is provided with a eccentric portion 1072 cooperating with the eccentric portion 1072 The rotating member 1071 is rotated to drive the lens holding member 102 to rotate around the first direction. Specifically, the limiting groove 1073 is a groove along the circumference of the lens holding member 102. The two side edges of the limiting groove 1073 along the optical axis direction are in contact with the eccentric part 1072 for limiting. Therefore, the rotating member 1071 can adjust the position of the eccentric part 1072 in the optical axis direction during rotation, and then drive the side of the lens holding member 102 to move in the optical axis direction through the eccentric part 1072, and finally drive the lens holding member 102 to tilt around the rotating bearing part 104. The tilt adjustment mechanism described in this embodiment has a simple structure, can omit the control member 1053 sleeved on the outer circumference of the base member 103, and has a more compact structure.

[0105] In addition, Fig.21 As shown, the entire lens 1 may remain stationary while the light valve 2 is tilted and adjusted, which can also achieve the goal of the image plane of the light valve, the plane of the lens and the screen intersecting in the same straight line, thereby obtaining a clear projection picture, thereby solving the problem of reduced resolution when the side projection angle is large, and effectively improving the quality of the projection picture. The rotation axis of the light valve 2 during tilt adjustment is perpendicular to and passes through the optical axis. Specifically, the position of the rotation axis is the center of the intersection of the light valve 2 and the optical axis.

[0106] like Fig. 22 As shown, the light valve 2 is an LCD panel, and the light valve 2 is arranged on a tilting mechanism, which includes a supporting body 41, a bearing member 42 and a driving assembly 43. The bearing member 42 is used to place the light valve 2, and the bearing member 42 is rotatably connected to the supporting body 41. The driving assembly 43 drives the bearing member 42 to deflect relative to the supporting body 41.

[0107] A pre-tightening mechanism is provided between the support body 41 and the bearing member 42 to eliminate the matching gap. The pre-tightening mechanism generates a pre-tightening force between the support body 41 and the bearing member 42, so that the bearing member 42 is kept in a tightly matched state relative to the support body 41, avoiding floating, vibration and other conditions of the light valve 2 on the bearing member 42 due to the existence of the matching gap, ensuring that the rotation of the bearing member 42 relative to the support body 41 is stable and accurate, which is conducive to ensuring that the light valve 2 can form a stable and clear picture after the rotation adjustment. The pre-tightening mechanism includes one or a combination of an elastic member 44, a magnetic component and a damping component. In this embodiment, the pre-tightening mechanism is composed of an elastic member 44, that is, the elastic member 44 is provided between the support body 41 and the bearing member 42, and the elastic member 44 always generates a biasing force in one direction between the support body 41 and the bearing member 42 to achieve a tightly matched state.

[0108] The driving component 43 includes a transmission mechanism of a gear and a rack, a worm gear transmission mechanism, and a pull rod transmission mechanism. In the present embodiment, the driving component 43 adopts a worm gear transmission mechanism, specifically, it includes a worm part 43 and a worm wheel part 44. The worm wheel part 44 is arranged on the bearing member 42, and specifically, the worm wheel part 44 can be integrally formed on the bearing member 42. The worm part 43 is meshed with the worm wheel part 44 for transmission. The worm part 43 is driven to rotate by a motor 45. The motor 45 is connected to the supporting body 41. Both ends of the worm part 43 are rotatably connected to the supporting body 41 to ensure the rotation stability of the worm part 43. A transmission gear is arranged on the worm part 43 to mesh with the transmission gear on the output shaft of the motor 45 for transmission. There is a fitting gap between the worm portion 43 and the worm wheel portion 44. Under the action of the elastic member 44, the load-bearing member 42 is biased in one direction relative to the supporting body 41, so that the worm portion 43 and the worm wheel portion 44 fit closely and eliminate the fitting gap, thereby effectively preventing the load-bearing member 42 from shaking relative to the supporting body 41.

[0109] Furthermore, the support body 41 is also provided with a detection sensor 46 for the tilting activity of the bearing member 42 to control the action of the driving assembly 43. Specifically, the bearing member 42 is provided with a trigger part 47 that cooperates with the detection sensor 46. The detection sensor 46 accurately detects the position movement of the trigger part 47 to determine the position of the bearing member 42 relative to the support body 41, thereby accurately controlling the driving assembly 43 to work so as to accurately rotate the light valve 2 on the bearing member 42 to a position, ensuring that the light valve 2 after tilt adjustment can reach the same straight line where the image plane of the light valve, the plane of the lens and the screen intersect, thereby ensuring that a clear projection picture can be obtained, solving the problem of reduced resolution when the side projection angle is large, and effectively improving the quality of the projection picture.

[0110] The above are only preferred embodiments of the present invention. It should be noted that the above preferred embodiments should not be regarded as limiting the present invention, and the protection scope of the present invention should be based on the scope defined by the claims. For ordinary technicians in this technical field, several improvements and modifications can be made without departing from the spirit and scope of the present invention, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A projection system, characterized in that: It comprises a lens and a light valve, wherein a part of the components in the lens or the whole lens is tilt-adjustable relative to the optical axis to form an adjustable component, and / or the light valve is tilt-adjustable relative to the optical axis.

2. The projection system according to claim 1, characterized in that: The adjustable component is a lens or lens group with the smallest absolute value of magnification in the lens; The lens is movable and adjustable in a plane perpendicular to the optical axis; The tilt adjustment direction of the adjustable component is consistent with the tilt direction of the projection screen relative to the optical axis when the magnification of the adjustable component is positive, and is opposite to the tilt direction of the projection screen relative to the optical axis when the magnification of the adjustable component is negative.

3. The projection system according to claim 1 or 2, characterized in that: The adjustable component includes a lens group or a single lens.

4. The projection system according to claim 1 or 2, characterized in that: The position of the rotation point of the adjustable component and / or the light valve during tilt adjustment is located on the optical axis.

5. The projection system according to claim 1 or 2, characterized in that: The lens is a six-lens structure, including a front lens group, an aperture and a rear lens group arranged from the magnification side to the reduction side, the front lens group includes lens 1 and lens 2 arranged from the magnification side to the reduction side, and the rear lens group includes lens 3, lens 4, lens 5 and lens 6 arranged from the magnification side to the reduction side; Alternatively, the lens is an eight-lens structure, including a front lens group, an aperture and a rear lens group arranged from the magnification side to the reduction side, the front lens group includes lens one, lens two and lens three arranged from the magnification side to the reduction side, and the rear lens group includes lens four, lens five, lens six, lens seven and lens eight arranged from the magnification side to the reduction side.

6. The projection system according to claim 5, characterized in that: The refractive power of the rear lens group is positive, the first lens is a negative lens, and the image circle diameter is 0≤φ≤75.4mm.

7. The projection system according to claim 5, characterized in that: In the lens with six-lens structure, the diopter of the lenses one to six is ​​negative, positive, negative, positive, positive, positive, respectively; In the lens with an eight-lens architecture, the refractive powers of lenses one to eight are negative, positive, positive, positive, negative, positive, positive, positive, and positive in sequence; or, the refractive powers of lenses one to eight are negative, positive, negative, negative, negative, positive, positive, and positive in sequence.

8. The projection system according to claim 5, characterized in that: In the lens with six-lens structure, the lens 1, lens 2, lens 5 and lens 6 are plastic aspherical lenses, and the remaining lenses are glass lenses; In the lens with eight-lens structure, lens one and lens two are plastic aspherical lenses, and the remaining lenses are glass lenses; or lens one and lens three are plastic aspherical lenses, and the remaining lenses are glass lenses.

9. The projection system according to claim 5, characterized in that: In the lens of the six-lens structure, the lens three and the lens four are connected to form a double cemented lens, the refractive index of the lens three is greater than the refractive index of the lens four, and the Abbe number of the lens three is less than the Abbe number of the lens four; In the lens with eight-lens structure, lens five and lens six are connected to form a double-cemented lens, and the refractive index of lens five is greater than the refractive index of lens six.

10. The projection system according to claim 1 or 2, characterized in that: The lens comprises a lens (101), a lens holding component (102) and a base component (103); the lens (101) is held on the lens holding component (102); the lens holding component (102) is rotatably connected to the base component (103) via a rotating bearing portion (104); the rotating axis of the rotating bearing portion (104) is a first direction perpendicular to the optical axis direction of the projection lens assembly; a tilt adjustment mechanism for driving the lens holding component (102) to tilt relative to the base component (103) is also provided between the lens holding component (102) and the base component (103); the tilt adjustment mechanism is provided in a direction perpendicular to the first direction.

11. The projection system according to claim 10, characterized in that: The rotating bearing part (104) comprises a roller (1041) and a pin (1042), wherein the pin (1042) is connected to the lens holding component (102), the roller (1041) is connected to an assembly hole provided on the base component (103), and the pin (1042) is connected to the roller (1041) in a rotationally matched manner; The outer wall of the roller (1041) is provided with a tapered surface, and the assembly hole is provided with a tapered portion that matches the tapered surface; or the roller (1041) is threadedly matched with the assembly hole to adjust the lens holding member (102) along the first direction.

12. The projection system according to claim 10, characterized in that: The tilt adjustment mechanism comprises a guide portion (1051), a guide groove (1052) and a control member (1053); the base member (103) is provided with a guide groove (1052) whose length direction is along the optical axis direction; the guide portion (1051) is connected to the lens holding member (102); the guide portion (101) moves along the guide groove (1052) to tilt the lens holding member (102); the control member (1053) is slidably connected to the base member (103) in a direction perpendicular to the optical axis; the control member (1053) is provided with a driving groove (1054) inclined relative to the optical axis direction; the guide portion (1051) is slidably matched with the driving groove (1054); the control member (1053) slides relative to the base member (103) to drive the guide portion (1051) to move along the guide groove (1052) through the driving groove (1054).

13. The projection system according to claim 1 or 2, characterized in that: The light valve is arranged on a tilting mechanism, and the tilting mechanism comprises a supporting body (41), a bearing member (42) and a driving assembly (43); the bearing member (42) is used to place the light valve; the bearing member (42) is rotatably connected to the supporting body (41); the driving assembly (43) drives the bearing member (42) to deflect relative to the supporting body (41); and a pre-tightening mechanism is arranged between the supporting body (41) and the bearing member (42).

Images