Long-focus short-focus adaptive diaphragm adjustment zoom lens and use method

Abstract

This invention discloses a telephoto / short focal length adaptive aperture zoom lens and its usage method, relating to the field of zoom lenses. It includes an external mechanism comprising a sleeve. The sleeve's inner cavity is provided with four outer frames, the outer surfaces of which are slidably connected to the inner surface of the external mechanism. The inner cavities of the four outer frames are respectively provided with a front fixed group, a first zoom group, a second zoom group, and a third zoom group. By assembling the front fixed group, the first zoom group, the second zoom group, and the third zoom group onto four independent outer frames and integrating them into the fixed sleeve via a sliding mechanism within the inner cavity, and cooperating with a precision drive mechanism composed of a voice coil motor and a transmission rod, an internal zoom structure with a constant optical length is achieved. This completely eliminates the volume change and center of gravity shift problems that occur when zooming with traditional telescopic lenses, significantly improving the aerodynamic stability and spatial adaptability of UAV platforms.

Description

Technical Field

[0001] This invention relates to zoom lens technology, specifically to a telephoto / short-focus adaptive aperture adjustment zoom lens and its usage method. Background Technology

[0002] With the widespread application of drones in aerial photography, inspection, surveying and mapping, higher requirements have been placed on the miniaturization, lightweighting and high zoom performance of airborne optical imaging systems. As a core component, zoom lenses usually achieve continuous changes in focal length by adjusting the interval between multiple lens groups, thereby expanding the field of view from the telephoto end to the short focal length end while maintaining image plane stability, thus meeting the dual needs of long-distance observation and wide-area coverage.

[0003] However, existing zoom lenses have obvious limitations: some adopt a telescopic structure, which causes the lens barrel to extend outward during zooming, resulting in dynamic changes in volume and a shift in the center of gravity, making it difficult to adapt to UAV platforms with limited space and strict requirements for aerodynamic stability; others adopt an internal zoom design, but due to limitations in optical structure or drive mechanism, the zoom range is small, and it cannot take into account both ultra-telephoto telephoto and ultra-wide-angle monitoring, which restricts the adaptability of UAVs in complex mission scenarios.

[0004] To address these issues, the applicant proposes a telephoto / short-focus adaptive aperture adjustment zoom lens and its usage method. Summary of the Invention

[0005] The purpose of this invention is to provide a telephoto and short-focal-length adaptive aperture adjustment zoom lens and its usage method, in order to solve the problems of existing zoom lenses, one type of which adopts an external lens barrel structure, resulting in a significant change in overall length during zooming, which easily disrupts the aerodynamic balance of the UAV; and another type, although it is an internal zoom form, is difficult to achieve a wide focal length coverage due to limitations in optical layout or drive method, and thus cannot simultaneously meet the needs of long-distance observation and large field of view monitoring.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a telephoto / short-focal-length adaptive aperture zoom lens, comprising an external mechanism, the external mechanism including a sleeve, the inner cavity of the sleeve being provided with four outer frames, the outer surfaces of the outer frames being slidably connected to the inner surfaces of the external mechanism, the inner cavities of the four outer frames being respectively provided with a front fixed group, a zoom group one, a zoom group two, and a zoom group three, the front fixed group including a first lens, a second lens, and a third lens, the zoom group one including a fourth lens, a fifth lens, and a sixth lens, the zoom group two including a seventh lens, an eighth lens, and a ninth lens, the zoom group three including a tenth lens, an eleventh lens, and a twelfth lens, a variable aperture assembly being provided on one side of the seventh lens, and the variable aperture assembly being mounted on one end of the corresponding outer frame.

[0007] Furthermore, the first lens, the second lens, and the third lens are respectively mounted on the inner surface of the corresponding outer frame via lens mounts.

[0008] Furthermore, the fourth lens, the fifth lens, and the sixth lens are respectively mounted on the inner surface of the corresponding outer frame via lens mounts.

[0009] Furthermore, the seventh lens, the eighth lens, and the ninth lens are respectively mounted on the inner surface of the corresponding outer frame via lens mounts.

[0010] Furthermore, the tenth lens, eleventh lens, and twelfth lens are respectively mounted on the inner surface of the corresponding outer frame via lens mounts.

[0011] Furthermore, the inner surface of the sleeve is provided with several limiting grooves, and several sliders are fixedly connected to the outer surfaces of several outer frames respectively, with one end of the slider slidably connected to the inner cavity of the corresponding limiting groove.

[0012] Furthermore, the inner surface of the sleeve has two mounting slots, and the outer surface of the sleeve is fixedly connected to two mounting boxes, the inner cavity of the mounting box communicating with the inner cavity of the corresponding mounting slot.

[0013] Furthermore, two voice coil motors are fixedly connected to one inner wall of the mounting box, and a transmission rod is fixedly connected to the output end of the voice coil motor. The end of the transmission rod away from the voice coil motor is fixedly connected to the outer surface of the corresponding outer frame.

[0014] A method for using a telephoto / short-focus adaptive aperture zoom lens includes the following steps:

[0015] S1. Input drive electrical signals to the four voice coil motors in the two mounting boxes respectively, and input aperture control signals to the variable aperture assembly;

[0016] S2. Four voice coil motors drive the corresponding outer frame to move along the axial direction of the sleeve through their respective transmission rods;

[0017] S3. The outer frame with the second zoom group moves synchronously, causing the variable aperture assembly fixed at one end of it to shift.

[0018] S4. The variable aperture assembly changes the opening angle of its internal blades according to the aperture control signal, so that the light-transmitting aperture is adjusted to the aperture value pre-associated with the axial position of the outer frame.

[0019] Compared with the prior art, the beneficial effects of the present invention are:

[0020] This design assembles the front fixed group, zoom group 1, zoom group 2, and zoom group 3 into four independent outer frames, which are then integrated into a fixed sleeve via an internal sliding mechanism. Combined with a precision drive mechanism consisting of a voice coil motor and a transmission rod, this achieves an internal zoom structure with a constant total optical length. This completely eliminates the volume changes and center of gravity shift issues associated with traditional telescopic lenses during zooming, significantly improving the aerodynamic stability and spatial adaptability of the UAV platform. Through the four-element optical architecture and the coordinated air gaps between the lens groups, 1x to 7x continuous zoom is achieved within a limited total optical length, with a focal length to total optical length ratio covering 0.209 to 1.465, catering to both ultra-wide-angle monitoring and ultra-telephoto observation needs. Simultaneously, the variable aperture assembly is fixed to the end of the outer frame corresponding to zoom group 2, moving synchronously with it and dynamically adjusting the aperture based on the axial position of the outer frame, ensuring precise F-number matching across the entire focal length range and effectively overcoming the defects of light imbalance and image quality degradation. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0022] Figure 1 This is a schematic diagram of the overall structure provided for an embodiment of the present invention;

[0023] Figure 2 This is a schematic diagram of the mounting box structure provided in an embodiment of the present invention;

[0024] Figure 3 This is a schematic diagram of the mounting slot structure provided in an embodiment of the present invention;

[0025] Figure 4 This is a schematic diagram of the outer frame structure provided in an embodiment of the present invention;

[0026] Figure 5 This is a schematic diagram of the voice coil motor structure provided in an embodiment of the present invention;

[0027] Figure 6 This is a schematic diagram of the third lens structure provided in an embodiment of the present invention.

[0028] Explanation of reference numerals in the attached figures:

[0029] 1. External mechanism; 101. Sleeve; 102. Limiting slide groove; 103. Mounting through groove; 104. Mounting box; 105. Voice coil motor; 106. Transmission rod; 107. Slider; 2. Outer frame; 3. Front fixed group; 301. First lens; 302. Second lens; 303. Third lens; 4. Zoom group 1; 401. Fourth lens; 402. Fifth lens; 403. Sixth lens; 5. Zoom group 2; 501. Seventh lens; 502. Eighth lens; 503. Ninth lens; 6. Zoom group 3; 601. Tenth lens; 602. Eleventh lens; 603. Twelfth lens. Detailed Implementation

[0030] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0031] As attached Figure 1 To be continued Figure 6 As shown:

[0032] Example 1:

[0033] This invention provides a telephoto / short-focus adaptive aperture zoom lens, comprising an external mechanism 1, which includes a sleeve 101. The inner cavity of the sleeve 101 is provided with four outer frames 2, the outer surfaces of which are slidably connected to the inner surfaces of the external mechanism 1. The inner cavities of the four outer frames 2 are respectively provided with a front fixed group 3, a zoom group 1 4, a zoom group 2 5, and a zoom group 3 6. The front fixed group 3 includes a first lens 301, a second lens 302, and a third lens 303. The zoom group 1 4 includes a fourth lens 401, a fifth lens 402, and a sixth lens 403. The zoom group 2 5 includes a seventh lens 501, an eighth lens 502, and a ninth lens 503. The zoom group 3 6 includes a tenth lens 601, an eleventh lens 602, and a twelfth lens 603. A variable aperture assembly is provided on one side of the seventh lens 501, and the variable aperture assembly is installed at one end of the corresponding outer frame 2.

[0034] Furthermore, the first lens 301, the second lens 302 and the third lens 303 are respectively mounted on the inner surface of the corresponding outer frame 2 via lens mounts.

[0035] Furthermore, the fourth lens 401, the fifth lens 402, and the sixth lens 403 are respectively mounted on the inner surface of the corresponding outer frame 2 via lens mounts.

[0036] Furthermore, the seventh lens 501, the eighth lens 502, and the ninth lens 503 are respectively mounted on the inner surface of the corresponding outer frame 2 via lens mounts.

[0037] Furthermore, the tenth lens 601, the eleventh lens 602 and the twelfth lens 603 are respectively mounted on the inner surface of the corresponding outer frame 2 via lens mounts.

[0038] Furthermore, the inner surface of the sleeve 101 is provided with a number of limiting grooves 102, and the outer surfaces of the several outer frames 2 are respectively fixedly connected with a number of sliders 107, one end of the slider 107 being slidably connected to the inner cavity of the corresponding limiting groove 102.

[0039] Furthermore, two mounting slots 103 are formed on the inner surface of the sleeve 101, and two mounting boxes 104 are fixedly connected to the outer surface of the sleeve 101. The inner cavity of the mounting box 104 communicates with the inner cavity of the corresponding mounting slot 103.

[0040] Furthermore, two voice coil motors 105 are fixedly connected to the inner wall of one side of the mounting box 104, and a transmission rod 106 is fixedly connected to the output end of the voice coil motor 105. The end of the transmission rod 106 away from the voice coil motor 105 is fixedly connected to the outer surface of the corresponding outer frame 2.

[0041] Working principle: The operator first fixes the sleeve 101 of the external mechanism 1 to the UAV payload platform. The four outer frames 2 respectively support the front fixed group 3, zoom group 1 4, zoom group 2 5, and zoom group 3 6 and slide them into the inner cavity of the sleeve 101. The front fixed group 3 is fixed to the inner surface of the corresponding outer frame 2 by the first lens 301, the second lens 302, and the third lens 303 through the lens mount. The zoom group 1 4 is fixed to the inner surface of the corresponding outer frame 2 by the fourth lens 401, the fifth lens 402, and the sixth lens 403 through the lens mount. The zoom group 2 5 is fixed to the inner surface of the corresponding outer frame 2 by the seventh lens 501, the eighth lens 502, and the ninth lens 503 through the lens mount. The zoom group 3 6 consists of the tenth lens 601, the eleventh lens 602, and the twelfth lens 603. 3. The lens is fixed to the inner surface of the corresponding outer frame 2 by the lens mount. The variable aperture assembly is installed at one end of the outer frame 2 corresponding to the zoom group 5 and is located on the object side of the seventh lens 501. When zooming is required, the control system inputs drive electrical signals to the four voice coil motors 105 in the two mounting boxes 104 respectively, and inputs aperture control signals to the variable aperture assembly. The four voice coil motors 105 push the corresponding outer frame 2 to move axially along the sleeve 101 through their respective transmission rods 106. During the movement, the outer frame 2 with the zoom group 5 is driven to move synchronously to the variable aperture assembly fixed at one end. The variable aperture assembly changes the opening and closing angle of its internal blades according to the aperture control signal, so that the light transmission aperture is adjusted to the aperture value pre-associated with the axial position of the outer frame 2.

[0042] This solution achieves an internal zoom structure with a constant optical length by assembling the front fixed group 3, zoom group 1 4, zoom group 2 5, and zoom group 3 6 onto four independent outer frames 2 and slidingly connecting them to the inner cavity of the fixed sleeve 101. Combined with a precision drive mechanism consisting of a voice coil motor 105 and a transmission rod 106, this completely avoids the dynamic volume changes and center of gravity shifts that occur during zooming in traditional telescopic lenses, significantly improving the aerodynamic stability and spatial adaptability of the UAV platform. Through a four-element optical architecture combined with a specific zoom interval curve, it successfully achieves a zoom structure within a limited optical range. It achieves high-magnification continuous zoom of 1 to 7x with a focal length to optical length ratio of 0.209 to 1.465, effectively meeting the dual requirements of ultra-telephoto telescope observation and ultra-wide-angle monitoring. In addition, by fixing the variable aperture assembly to one end of the outer frame 2 corresponding to the zoom group 5 and moving it synchronously, and dynamically adjusting it according to the preset matching aperture value based on the axial position of the outer frame 2, it ensures accurate matching of F number and optimal imaging quality at different focal lengths, overcoming the defects of light imbalance and image quality degradation caused by fixed aperture or non-coordinated adjustment.

[0043] Example 2:

[0044] The lens images onto a 1-inch image sensor, achieving 1x to 7x continuous zoom, with a constant total optical length TTL and a focal length to total optical length ratio ranging from 0.209 to 1.465.

[0045] The front fixed assembly 3 consists of a first lens 301, a second lens 302, and a third lens 303. The first lens 301 is a spherical lens with positive power, an object-side radius of curvature of 24.40124 mm, a thickness of 2.584222 mm, and is made of optical glass with a refractive index of 1.62041 and an Abbe number of 60.3236. The second lens 302 is a spherical lens with negative power, an object-side radius of curvature of 82.26784 mm, and a center thickness of 0.05 mm. The third lens 303 is a spherical lens with positive power, an object-side radius of curvature of 18.80973 mm, a thickness of 2.858518 mm, and is made of optical glass with a refractive index of 1.50193 and an Abbe number of 68.8604.

[0046] The zoom group 4 consists of a fourth lens 401, a fifth lens 402, and a sixth lens 403. The fourth lens 401 is a negative power Qcon aspherical lens with an object-side radius of curvature of -785.158 mm and a thickness of 0.5 mm, made of optical glass with a refractive index of 1.75444 and an Abbe number of 28.3066. The fifth lens 402 is a positive power Qcon aspherical lens with an object-side radius of curvature of 26.01871 mm and a center thickness of 1.00586 mm. The sixth lens 403 is a positive power Qcon aspherical lens with an object-side radius of curvature of 38.41955 mm and a thickness of 0.3 mm, made of optical glass with a refractive index of 1.62041 and an Abbe number of 60.3236.

[0047] The zoom group 5 consists of a seventh lens 501, an eighth lens 502, and a ninth lens 503. The seventh lens 501 is a positive power Qcon aspherical lens with an object-side radius of curvature of 5.485922 mm and a thickness of 2.209701 mm, made of optical glass with a refractive index of 1.75520 and an Abbe number of 27.5795. The eighth lens 502 is a negative power Qcon aspherical lens with an object-side radius of curvature of 4.652222 mm and a center thickness of 2.319183 mm. The ninth lens 503 is a positive power Qcon aspherical lens with an object-side radius of curvature of -111.408 mm and a thickness of 0.4 mm, made of optical glass with a refractive index of 1.62041 and an Abbe number of 60.3236.

[0048] The zoom group 6 consists of the tenth lens 601, the eleventh lens 602, and the twelfth lens 603. The tenth lens 601 is a positive power Qcon aspherical lens with an object-side radius of curvature of 13.50055 mm and a thickness of 0.538844 mm. It is made of optical glass with a refractive index of 1.48749 and an Abbe number of 70.4058. The eleventh lens 602 is a negative power Qcon aspherical lens with an object-side radius of curvature of 5.101937 mm and a thickness of 2.512155 mm. It is also made of optical glass with a refractive index of 1.48749 and an Abbe number of 70.4058. The twelfth lens 603 is a positive power Qcon aspherical lens with an object-side radius of curvature of 4.46101 mm and a thickness of 0.908651 mm. It is also made of optical glass with a refractive index of 1.48749 and an Abbe number of 70.4058.

[0049] During zooming, the air gaps between the front fixed group 3 and zoom group 1 4, zoom group 1 4 and zoom group 2 5, zoom group 2 5 and zoom group 3 6, and zoom group 3 6 and the image plane are used as zoom intervals, which are adjusted in conjunction with a specific zoom curve. Specifically, at the short focal length end, the corresponding plane numbers s6, s12, s19, and s25 of the above key intervals are 0.997mm, 11.322mm, 0.050mm, and 3.200mm, respectively; at the medium focal length end, they are adjusted to 10.618mm, 2.160mm, 0.389mm, and 2.392mm, respectively; and at the telephoto end, they are further adjusted to 12.944mm, 0.291mm, 0.634mm, and 1.703mm.

[0050] The variable aperture assembly is precisely positioned on the object side of the seventh lens 501 and mounted at one end of the outer frame 2 corresponding to the zoom group 2, moving as a whole with the zoom group 2. Simultaneously, this variable aperture assembly dynamically adjusts its aperture size according to the zoom position to match the F-number requirements at different focal lengths, ensuring optimal image quality across the entire zoom range. The entire optical system is optimized for a wide spectral range from 430nm to 1000nm, effectively adapting to photographic needs in various complex lighting environments, from sunrise and sunset to nighttime infrared.

[0051] Table 1: Optical parameters of each lens element in a zoom lens:

[0052] First lens 301 Front fixed group 3 spherical 24.40124 2.584222 1.62041 / 60.3236 Second lens 302 Front fixed group 3 spherical 82.26784 0.05 - Third lens 303 Front fixed group 3 spherical 18.80973 2.858518 1.50193 / 68.8604 Fourth lens 401 Zoom Group 4 Qcon aspherical surface -785.158 0.5 1.75444 / 28.3066 Fifth lens 402 Zoom Group 4 Qcon aspherical surface 26.01871 1.00586 - Sixth lens 403 Zoom Group 4 Qcon aspherical surface 38.41955 0.3 1.62041 / 60.3236 Seventh Lens 501 Zoom Group 2 5 Qcon aspherical surface 5.485922 2.209701 1.75520 / 27.5795 Eighth lens 502 Zoom Group 2 5 Qcon aspherical surface 4.652222 2.319183 - Ninth Lens 503 Zoom Group 2 5 Qcon aspherical surface -111.408 0.4 1.62041 / 60.3236 Tenth Lens 601 Zoom 3 groups 6 Qcon aspherical surface 13.50055 0.538844 1.48749 / 70.4058 Eleventh Lens 602 Zoom 3 groups 6 Qcon aspherical surface -229.305 0.05 - The twelfth lens 603 Zoom 3 groups 6 Qcon aspherical surface 4.46101 0.908651 1.48749 / 70.4058

[0053] Table 2: Zoom interval values ​​at different focal lengths

[0054] Between the front fixed group 3 and the zoom group 4 s6 0.997 10.618 12.944 Between zoom group 4 and zoom group 5 s12 11.322 2.16 0.291 Between zoom group 5 of zoom 2 and zoom group 6 of zoom 3 s19 0.05 0.389 0.634 Between zoom group 3 and image plane s25 3.2 2.392 1.703

[0055] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A telephoto / short-focus adaptive aperture zoom lens, comprising an external mechanism (1), characterized in that, The external mechanism (1) includes a sleeve (101), and the inner cavity of the sleeve (101) is provided with four outer frames (2). The outer surface of the outer frame (2) is slidably connected to the inner surface of the external mechanism (1). The inner cavities of the four outer frames (2) are respectively provided with a front fixed group (3), a zoom group 1 (4), a zoom group 2 (5), and a zoom group 3 (6). The front fixed group (3) includes a first lens (301), a second lens (302), and a third lens (303). The zoom group 1... Group (4) includes a fourth lens (401), a fifth lens (402) and a sixth lens (403). The zoom group 2 (5) includes a seventh lens (501), an eighth lens (502) and a ninth lens (503). The zoom group 3 (6) includes a tenth lens (601), an eleventh lens (602) and a twelfth lens (603). A variable aperture assembly is provided on one side of the seventh lens (501), and the variable aperture assembly is installed at one end of the corresponding outer frame (2).

2. The telephoto / short focal length adaptive aperture adjustment zoom lens according to claim 1, characterized in that, The first lens (301), the second lens (302) and the third lens (303) are respectively mounted on the inner surface of the corresponding outer frame (2) via lens mounts.

3. The telephoto / short focal length adaptive aperture adjustment zoom lens according to claim 1, characterized in that, The fourth lens (401), the fifth lens (402) and the sixth lens (403) are respectively mounted on the inner surface of the corresponding outer frame (2) via lens mounts.

4. The telephoto / short focal length adaptive aperture adjustment zoom lens according to claim 1, characterized in that, The seventh lens (501), the eighth lens (502) and the ninth lens (503) are respectively mounted on the inner surface of the corresponding outer frame (2) via lens mounts.

5. A telephoto / short-focus adaptive aperture adjustment zoom lens according to claim 1, characterized in that, The tenth lens (601), eleventh lens (602) and twelfth lens (603) are respectively mounted on the inner surface of the corresponding outer frame (2) via lens mounts.

6. A telephoto / short-focus adaptive aperture adjustment zoom lens according to claim 1, characterized in that, The inner surface of the sleeve (101) is provided with several limiting grooves (102), and several sliders (107) are fixedly connected to the outer surfaces of several outer frames (2). One end of the slider (107) is slidably connected to the inner cavity of the corresponding limiting groove (102).

7. A telephoto / short-focus adaptive aperture adjustment zoom lens according to claim 1, characterized in that, The inner surface of the sleeve (101) has two mounting slots (103), and the outer surface of the sleeve (101) is fixedly connected to two mounting boxes (104). The inner cavity of the mounting box (104) is connected to the inner cavity of the corresponding mounting slot (103).

8. A telephoto / short-focus adaptive aperture adjustment zoom lens according to claim 7, characterized in that, Two voice coil motors (105) are fixedly connected to one side of the inner wall of the mounting box (104), and a transmission rod (106) is fixedly connected to the output end of the voice coil motor (105). The end of the transmission rod (106) away from the voice coil motor (105) is fixedly connected to the outer surface of the corresponding outer frame (2).

9. A method of using a telephoto / short-focus adaptive aperture zoom lens according to any one of claims 1 to 8, characterized in that, Includes the following steps: S1. Input drive electrical signals to the four voice coil motors (105) in the two mounting boxes (104) respectively, and input aperture control signals to the variable aperture assembly; S2. Four voice coil motors (105) push the corresponding outer frame (2) to move along the axial direction of the sleeve (101) through their respective transmission rods (106); S3. The outer frame (2) with zoom group 2 (5) installed drives the variable aperture assembly fixed at one end of it to move synchronously during the movement. S4. The variable aperture assembly changes the opening angle of its internal blades according to the aperture control signal, so that the light-transmitting aperture is adjusted to the aperture value pre-associated with the axial position of the outer frame (2).

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