Zoom attachment module, optical assembly and projector cooperating with an LCD projection lens

Abstract

The application relates to a zoom additional module matched with an LCD projection lens. The zoom additional module is designed to be movably assembled and disassembled with the LCD projection lens, can be flexibly added or disassembled according to requirements, and after disassembly, the original LCD projection lens can still work independently. Through the design, the original LCD projection lens does not need to be transformed or replaced, and zooming is realized only by adding additional components of a front fixed group and a zoom group, thereby reducing the dependence on complex structure and high value lenses. Through the design, the distance between the front fixed group and the imaging field lens is constant, so that stable optical reference is provided when the components move, and the problem of image quality decline in the zooming process is avoided.

Description

Technical Field

[0001] This application relates to the field of projection lenses, and more particularly to zoom add-on modules, optical components and projectors used with LCD projection lenses. Background Technology

[0002] In the projection equipment field, LCD projector optical engines are seeing their market share steadily increase due to their high cost-effectiveness and continuously improving optical performance. Meanwhile, as DLP, LCoS, and other types of projectors increasingly incorporate zoom capabilities, the market has also created a clear demand for zoom functionality in LCD projectors, hoping they can achieve flexible adjustment of screen size while maintaining cost advantages.

[0003] In existing technologies, to meet the zoom requirements of LCD projection, some devices directly borrow the zoom structure from DLP and LCoS projection, employing an integrated zoom lens design that includes a front fixed group, a zoom group, a compensation group, and a rear fixed group. However, due to the large size of LCD projection image sources, the lens aperture needs to be increased accordingly to adapt to this type of image source, and the number of lenses also needs to be increased to ensure optical performance. This directly leads to a significant increase in lens manufacturing costs, making the cost of this type of solution far higher than the acceptable cost-performance range in the market.

[0004] Therefore, there is a need for a detachable zoom add-on module, optical components, and projector that can be used with an LCD projection lens to achieve zoom functionality. Utility Model Content

[0005] The purpose of this application is to provide a detachable zoom add-on module, optical components, and projector that can be used in conjunction with an LCD projection lens to achieve zoom functionality.

[0006] According to one aspect of this application, a zoom attachment module for use with an LCD projection lens is provided. The zoom attachment module is movably mounted on the LCD projection lens. An imaging frosted lens and an LCD screen are sequentially arranged on the side of the LCD projection lens facing away from the zoom attachment module. The zoom attachment module includes: The front fixing assembly is located on the side of the LCD projection lens that is away from the imaging Fresnel lens. A zoom module is located between the front fixed module and the LCD projection lens, wherein... The distance between the front fixed group and the imaging focal length lens remains constant. The direction perpendicular to the imaging focal length lens is denoted as the optical axis direction. The zoom group and the LCD projection lens are movable along the optical axis direction between the front fixed group and the imaging focal length lens.

[0007] In at least one embodiment of this application, the front fixation group consists of one or more lenses, and the zoom group consists of one or more lenses.

[0008] In at least one embodiment of this application, when zoom is not required, the zoom attachment module is removed, and the image source on the LCD screen is projected onto an external screen after passing through the imaging lens and the LCD projection lens in sequence.

[0009] In at least one embodiment of this application, when zooming is required, the zoom attachment module is mounted on the LCD projection lens, and the image source on the LCD screen is projected onto an external screen after passing through the imaging lens, the LCD projection lens, and the zoom attachment module in sequence.

[0010] In at least one embodiment of this application, when the zoom attachment module is installed on the LCD projection lens, the size of the image projected on the external screen becomes larger, and the LCD projection lens moves along the optical axis to adjust the focus.

[0011] In at least one embodiment of this application, when the zoom attachment is mounted on the LCD projection lens and it is necessary to further magnify the image size projected on the external screen, the LCD projection lens moves closer to the LCD screen along the optical axis, and the zoom group moves in the same direction as the LCD projection lens.

[0012] In at least one embodiment of this application, the distance by which the LCD projection lens moves closer to the LCD screen along the optical axis is denoted as R, and the distance by which the zoom group moves in the same direction as the LCD projection lens is denoted as L, satisfying the following relationship: R≠L.

[0013] In at least one embodiment of this application, the front fixation group is located between the external screen and the zoom group, and the distance between the front fixation group and the imaging lens remains constant to correct field curvature and distortion. The zoom group is movably disposed between the front fixed group and the LCD projection lens along the optical axis, so as to change the focal length of the optical path by moving along the optical axis. The LCD projection lens is movably disposed between the zoom group and the imaging lens along the optical axis. The LCD projection lens has positive optical power and is used for focusing imaging and correcting aberrations. The imaging Fresnel lens is located on the side of the LCD screen near the LCD projection lens, and the imaging Fresnel lens is used to provide compensation for telecentricity and final focus.

[0014] According to one aspect of this application, an optical component is provided, including any of the zoom attachment modules described above that work in conjunction with an LCD projection lens.

[0015] According to one aspect of this application, a projector is provided, including the aforementioned optical components.

[0016] This application has the following beneficial effects: (1) The zoom add-on module and the LCD projection lens are movable and can be detached and assembled. They can be flexibly added or removed as needed. After disassembly, the original LCD projection lens can still work independently. (2) No modification or replacement of the original LCD projection lens is required. Zooming is achieved by adding additional components to the front fixed group and zoom group, reducing the reliance on complex and high-value lenses. (3) The distance between the front fixed group and the imaging lens is constant in order to provide a stable optical reference when the components move, and to avoid the problem of image quality degradation during zooming. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the structure of a zoom auxiliary module for use with an LCD projection lens according to an embodiment of this application; Figure 2 This is a schematic diagram of the structure of the LCD projection lens when the zoom attachment module is disassembled in one embodiment of this application; Explanation of icon numbers: 100. A zoom auxiliary module for use with an LCD projection lens; 10. LCD screen; 20. Imaging lens; 30. LCD projection lens; 40. Zoom auxiliary module; 41. Zoom group; 42. Front fixing group; F. Optical axis direction. Detailed Implementation

[0019] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings. Preferred embodiments of this application are shown in the drawings. However, this application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of this application.

[0020] It should be noted that when a component is said to be "fixed to" another component, it can be directly attached to the other component or there may be an intervening component. When a component is said to be "connected to" another component, it can be directly connected to the other component or there may be an intervening component. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the specification of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0022] Please refer to Figure 1 - Figure 2 One embodiment of this application provides a zoom attachment module 40 that works in conjunction with an LCD projection lens 30. The zoom attachment module 40 is movably mounted on the LCD projection lens 30. On the side of the LCD projection lens 30 away from the zoom attachment module 40, an imaging lens 20 and an LCD screen 10 are arranged in sequence. The zoom attachment module 40 includes a front fixed group 42 and a zoom group 41.

[0023] The front fixing group 42 is located on the side of the LCD projection lens 30 opposite to the imaging fractal lens 20, and the zoom group 41 is located between the front fixing group 42 and the LCD projection lens 30. The distance between the front fixing group 42 and the imaging fractal lens 20 remains constant. The direction perpendicular to the imaging fractal lens 20 is denoted as the optical axis direction F. The zoom group 41 and the projection lens are movable along the optical axis direction F between the front fixing group 42 and the imaging fractal lens 20.

[0024] Specifically, from the perspective of the optical path sequence, from the LCD screen to the direction of light emission, the light passes through the complete optical path of LCD screen → imaging lens 20, LCD projection lens 30, zoom group 41, and front fixed group 42 in sequence, ensuring that the light passes through each component in sequence after starting from the image source of LCD screen 10.

[0025] Furthermore, the front fixed group 42 is located on the side of the LCD projection lens 30 away from the imaging lens 20. It performs final aberration correction on the light passing through the LCD projection lens 30 and the zoom group 41, solving image distortion problems such as field curvature and distortion that may occur due to component movement during zooming, ensuring that the sharpness of the edge and center of the image is consistent; and it can also prevent light from introducing aberrations again in subsequent propagation, thus improving image quality.

[0026] The distance between the front fixed group 42 and the imaging lens 20 remains constant, ensuring that the aberration correction effect of the front fixed group 42 is not affected by the movement of the zoom group 41 and the LCD projection lens 30, thus forming a stable reference optical path.

[0027] The zoom group 41 is located between the front fixed group 42 and the LCD projection lens 30. By moving along the optical axis, it changes the relative distance with the LCD projection lens 30 and the front fixed group 42, thereby adjusting the equivalent focal length of the entire optical path and achieving image scaling. In combination with the front fixed group 42, aberrations are corrected in real time during zooming, avoiding image quality degradation caused by moving the zoom group 41 alone.

[0028] Furthermore, the front fixed group 42 corrects field curvature and distortion at a constant position, the zoom group 41 adjusts the focal length by moving, the LCD projection lens 30 adjusts the focus by moving, the LCD projection lens 30 retains the original positive optical power to undertake the main optical power and aberration correction, and the imaging Fresnel lens 20 maintains the telecentricity and focus compensation function. The multi-component collaboration ensures stable image quality during zooming and overcomes the image quality degradation problem that may be caused by simple zoom design.

[0029] In one specific embodiment, the front fixation group 42 consists of one or more lenses, and the zoom group 41 consists of one or more lenses.

[0030] Specifically, the number of lenses can be flexibly selected as one or more, avoiding the high costs associated with large-diameter lenses and multiple structures. At the same time, the original LCD projection lens 30 still provides the main optical power, reducing the dependence on the module's optical performance and further lowering the module's design and manufacturing costs.

[0031] Furthermore, when the need for correction of image distortion and field curvature is low, the front fixation group 42 can use a single lens with a specific curvature, material, or coating to achieve basic correction through a single optical refraction. This design simplifies the structure to the maximum extent, reduces material and processing costs, and at the same time reduces lens reflection loss in the optical path and improves light transmittance.

[0032] When high image quality is required, the front fixed group 42 can use a combination of multiple lenses (such as two lenses with different refractive indices cemented together, or multiple lenses arranged at specific intervals). Multiple lenses can work synergistically through complementary optical properties to significantly improve aberration correction accuracy and avoid the problem of incomplete correction caused by the optical limitations of a single lens.

[0033] Furthermore, when the zoom range is small and the tolerance for image sharpness fluctuations is high, a single lens of the zoom group 41 can be moved to change its relative distance to the LCD projection lens 30 and the front fixed group 42, thereby achieving focus adjustment. This reduces the weight of the moving components and lowers the load and control difficulty of the drive mechanism.

[0034] When a wider zoom range is required or image quality stability is required during zooming, the multi-lens combination of zoom group 41 can expand the focal length adjustment range by moving in tandem.

[0035] In one specific embodiment, when zoom is not required, the zoom attachment module 40 is removed, and the image source on the LCD screen 10 is projected onto an external screen after passing through the imaging lens 20 and the LCD projection lens 30 in sequence.

[0036] Specifically, when the zoom attachment module 40 is removed, the conventional imaging path from the optical path to the LCD projector is: LCD screen (image source), imaging Fresnel lens 20, LCD projection lens 30, and external screen. This ensures that the device can still operate stably in its original state and output a basic projected image that meets expectations when zoom is not required.

[0037] In one specific embodiment, when zooming is required, the zoom attachment module 40 is mounted on the LCD projection lens 30, and the image source on the LCD screen 10 is projected onto an external screen after passing through the imaging lens 20, the LCD projection lens 30, and the zoom attachment module 40 in sequence.

[0038] Specifically, when the zoom add-on module 40 is installed, the optical path flow sequence is as follows: LCD screen 10 (image source), imaging Fresnel lens 20, LCD projection lens 30, zoom group 41, front fixing group 42 to the external screen. The zoom add-on module 40 only needs to be installed on the existing LCD projection lens 30, without replacing the LCD screen 10, imaging Fresnel lens 20, or LCD projection lens 30, making it compatible with existing devices, such as LCD projectors already purchased for home or office use.

[0039] In one specific embodiment, when the zoom attachment module 40 is installed on the LCD projection lens 30, the size of the image projected on the external screen becomes larger, and the LCD projection lens 30 moves along the optical axis direction F to adjust the focus.

[0040] Specifically, after the zoom add-on module 40 is installed, the equivalent focal length of the entire optical system is increased. According to the principle of projection imaging, with the projection distance remaining unchanged, the increase in equivalent focal length directly results in a larger image size projected onto the external screen.

[0041] After the zoom attachment module 40 is added, the equivalent focal length of the original optical path changes, and the initial focal length of the original LCD projection lens 30 shifts from the focal point of the new optical path, which may cause the image to be blurry. At this time, the LCD projection lens 30 moves along the optical axis direction F, that is, along the direction closer to or farther from the LCD screen, which can adjust its relative distance with the image source of the LCD screen and the zoom group 41, and rematch the focal length of the new optical path to restore the image to clarity.

[0042] In one specific embodiment, when the zoom attachment module 40 is installed on the LCD projection lens 30 and it is necessary to further enlarge the size of the image projected on the external screen, the LCD projection lens 30 moves closer to the LCD screen 10 along the optical axis direction F, and the zoom group 41 moves in the same direction as the LCD projection lens 30.

[0043] Specifically, with the projection distance remaining constant, the core of increasing the image size is to increase the equivalent focal length of the optical system. When the zoom module 40 is installed, if it is necessary to further enlarge the image size, the focal length needs to be adjusted by moving the zoom group 41, and the focus needs to be adjusted in conjunction with the movement of the LCD projection lens 30.

[0044] Furthermore, the LCD projection lens 30 bears the main optical focal length. As it moves toward the image source of the LCD screen 10, the distance between the lens and the image source decreases. According to the lens imaging formula, the decrease in object distance leads to an increase in image distance, which in turn causes the focal point of the light to shift away from the lens. The movement of the zoom group 41 can jointly extend the equivalent focal length, providing the basic optical conditions for further magnification of the image.

[0045] Furthermore, the zoom group 41 is located between the lens and the front fixed group 42, and when it moves toward the LCD screen 10 together with the LCD projection lens 30, the relative distance between it and the lens can be adjusted. By changing the interval between the zoom group 41 and the lens in the optical path, the increase in the equivalent focal length can be controlled.

[0046] In one specific embodiment, the distance by which the LCD projection lens 30 moves closer to the LCD screen 10 along the optical axis direction F is denoted as R, and the distance by which the zoom group 41 moves in the same direction as the LCD projection lens 30 is denoted as L, satisfying the relationship: R≠L.

[0047] Specifically, when the LCD projection lens 30 and the zoom group 41 move in the same direction toward the LCD screen, if the two move the same distance, i.e., R=L, then their relative positions do not change, and the increase in the equivalent focal length will be limited, making it impossible to meet the need to further enlarge the screen size.

[0048] Furthermore, by utilizing the movement difference between the zoom group 41 and the LCD projection lens 30, the aberration characteristics of the lens and the zoom group 41 are made complementary. The spherical aberration generated by the lens movement is canceled out by the negative spherical aberration generated by the movement of the zoom group 41. Combined with the correction effect of the front fixed group 42, it is ensured that there is no significant distortion, blurring, or brightness reduction in the image during zooming, and that the magnified image remains clear. Therefore, there is no need to design an additional compensation group; aberrations can be canceled out simply by the same-direction movement difference between the lens and the zoom group 41, reducing the number of lenses and mechanical structures, thereby reducing costs.

[0049] In one specific embodiment, the front fixation group 42 is located between the external screen and the zoom group 41, and the distance between the front fixation group 42 and the imaging Fresnel lens 20 remains constant to correct field curvature and distortion. The zoom group 41 is movably disposed between the front fixed group 42 and the LCD projection lens 30 along the optical axis direction F, so as to change the focal length of the optical path by moving along the optical axis direction F. The LCD projection lens 30 is movably disposed between the zoom group 41 and the imaging lens 20 along the optical axis direction F. The LCD projection lens 30 has positive optical power and is used for focusing imaging and correcting aberrations. The imaging Fresnel lens 20 is disposed on the side of the LCD screen 10 near the LCD projection lens 30, and the imaging Fresnel lens 20 is used to provide compensation for telecentricity and final focus.

[0050] This application provides an optical component, including a zoom attachment module 40 that works with an LCD projection lens 30 as described in any of the above applications.

[0051] This application provides a projector including the aforementioned optical components.

[0052] Therefore, the zoom attachment module 40 provided above, which works in conjunction with the LCD projection lens 30, is designed to be movably attached and detached from the LCD projection lens 30. It can be flexibly added or removed as needed. After removal, the original LCD projection lens 30 can still work independently. The design eliminates the need to modify or replace the original LCD projection lens 30. Zooming is achieved simply by adding additional components to the front fixed group 42 and the zoom group 41, reducing reliance on complex, high-value lenses. The design ensures a constant distance between the front fixed group 42 and the imaging fret lens 20, providing a stable optical reference when components move and preventing image quality degradation during zooming.

[0053] The embodiments described above are merely illustrative of several implementations of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the scope of protection of this application. Therefore, the scope of protection of this patent application should be determined by the appended claims.

Claims

1. A zoom attachment module for use with an LCD projection lens, characterized in that, The zoom attachment module is detachably mounted on the LCD projection lens. An imaging frosted lens and an LCD screen are sequentially arranged on the side of the LCD projection lens opposite to the zoom attachment module. The zoom attachment module includes: The front fixing assembly is located on the side of the LCD projection lens that is away from the imaging Fresnel lens. A zoom module is located between the front fixed module and the LCD projection lens, wherein... The distance between the front fixed group and the imaging focal length lens remains constant. The direction perpendicular to the imaging focal length lens is denoted as the optical axis direction. The zoom group and the LCD projection lens are movable along the optical axis direction between the front fixed group and the imaging focal length lens.

2. The zoom auxiliary module for use with an LCD projection lens according to claim 1, characterized in that, The front fixation group consists of one or more lenses, and the zoom group consists of one or more lenses.

3. The zoom auxiliary module for use with an LCD projection lens according to claim 1, characterized in that, When zoom is not required, the zoom attachment module is removed, and the image source on the LCD screen is projected onto an external screen after passing through the imaging lens and the LCD projection lens in sequence.

4. The zoom auxiliary module for use with an LCD projection lens according to claim 1, characterized in that, When zooming is required, the zoom attachment module is installed on the LCD projection lens, and the image source on the LCD screen is projected onto the external screen after passing through the imaging lens, the LCD projection lens and the zoom attachment module in sequence.

5. The zoom auxiliary module for use with an LCD projection lens according to claim 1, characterized in that, When the zoom attachment module is installed on the LCD projection lens, the size of the image projected onto the external screen becomes larger, and the LCD projection lens moves along the optical axis to adjust the focus.

6. The zoom auxiliary module for use with an LCD projection lens according to claim 5, characterized in that, When the zoom module is installed on the LCD projection lens and it is necessary to further enlarge the size of the image projected on the external screen, the LCD projection lens moves closer to the LCD screen along the optical axis, and the zoom module moves in the same direction as the LCD projection lens.

7. The zoom auxiliary module for use with an LCD projection lens according to claim 6, characterized in that, The distance the LCD projection lens moves closer to the LCD screen along the optical axis is denoted as R, and the distance the zoom group moves in the same direction as the LCD projection lens is denoted as L, satisfying the following relationship: R≠L.

8. The zoom auxiliary module for use with an LCD projection lens according to claim 1, characterized in that, The front fixation group is located between the external screen and the zoom group, and the distance between the front fixation group and the imaging lens remains constant to correct field curvature and distortion. The zoom group is movably disposed between the front fixed group and the LCD projection lens along the optical axis, so as to change the focal length of the optical path by moving along the optical axis. The LCD projection lens is movably disposed between the zoom group and the imaging lens along the optical axis. The LCD projection lens has positive optical power and is used for focusing imaging and correcting aberrations. The imaging Fresnel lens is located on the side of the LCD screen near the LCD projection lens, and the imaging Fresnel lens is used to provide compensation for telecentricity and final focus.

9. An optical component, characterized in that, Includes the zoom attachment module that works with an LCD projection lens as described in any one of claims 1-8.

10. A projector, characterized in that, Includes the optical components as described in claim 9.

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