Scheimpflug lens and electronic device

Abstract

A Scheimpflug lens and an electronic device. The Scheimpflug lens comprises a plurality of optical lenses arranged coaxially in sequence from an object side to an image side. By enabling the outer diameter of the optical lens closest to the object side to be smaller than the outer diameter of the optical lens closest to the image side, a lens optical path structure having a small front part and a large rear part is formed, so that the light receiving capacity of the lens is effectively increased, providing the possibility for high-speed measurement; and by setting an incident surface of the optical lens closest to the object side and an emergent surface of the optical lens closest to the image side as concave surfaces, imaging of a large field of view and of a large target surface is satisfied under the limitation of ensuring the overall appearance size of the lens. In addition, by reasonably setting performance parameters of the optical lenses, the aperture number of the Scheimpflug lens is optimized to F1.2 to F2.0, so that the light receiving capability is improved, and the FOV is 200 mm to 550 mm.

Description

Sham lens and electronic equipment

[0001] This disclosure claims priority to the Chinese patent application filed with the China Patent Office on June 30, 2023, with application number 202310807182.2 and invention name “Sham Lens and Electronic Device,” the entire contents of which are incorporated herein by reference. Technical Field

[0002] The present disclosure relates to the field of optical technology, and in particular to a Sham lens and electronic equipment. Background Art

[0003] A Sham lens is a lens that uses Sham's law to form an image. According to Sham's law, when the extended lines of the target plane, the main surface of the lens, and the detector plane intersect in a line, a clear image of the entire tilted target field of view can be formed.

[0004] In some practical applications, the captured area is large, requiring a Sham lens with a wide field of view and compatible with a camera chip with a large image sensor. However, when a Sham lens is directly applied to a camera, the optical axis of the Sham lens is no longer perpendicular to the camera chip surface. This causes the cover glass on the chip surface to deviate from the lens' optical axis, resulting in reduced image clarity. Ensuring clear imaging within a large field of view has become a key research area for Sham lenses. Technical Solutions

[0005] The present disclosure provides a Sham lens and electronic equipment to adapt to a large-surface camera, which has a large-field imaging capability and high light-receiving capability.

[0006] In order to solve the above technical problems, the present disclosure adopts the following technical solutions:

[0007] A first aspect of the present disclosure provides a Sham lens, comprising a plurality of lenses coaxially arranged in sequence from the object side to the image side, wherein the outer diameter of the lens closest to the object side is smaller than the outer diameter of the lens closest to the image side; the incident surface of the lens closest to the object side is concave; and the exit surface of the lens closest to the image side is concave.

[0008] Compared with the prior art, the Sham lens provided by the first aspect of the present disclosure has the following advantages:

[0009] The Sham lens disclosed herein comprises a plurality of lenses arranged coaxially from the object side to the image side. By making the outer diameter of the lens closest to the object side smaller than that of the lens closest to the image side, a lens optical path architecture is formed with a smaller front and a larger rear. This effectively increases the lens's light-receiving capacity, facilitating its application in high-speed measurement. By setting both the incident surface of the lens closest to the object side and the exit surface of the lens closest to the image side as concave, the lens achieves imaging of a wide field of view and a large target surface while maintaining the overall dimensions of the lens. Furthermore, by rationally configuring the performance parameters of each lens, the Sham lens's aperture is optimized to F1.2 to F2.0, improving light-receiving capacity and achieving a field of view (FOV) of 200 mm to 550 mm.

[0010] As an improvement of the above-mentioned Sham lens disclosed in the present invention, the outer diameter D1 of the lens closest to the object side and the outer diameter D9 of the lens closest to the image side satisfy 0.3<D1 / D9<0.8.

[0011] As an improvement to the above-mentioned Sham lens disclosed herein, the Sham lens includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, and a ninth lens coaxially arranged in sequence from the object side to the image side; wherein the first lens is the lens closest to the object side; and the ninth lens is the lens closest to the image side.

[0012] As an improvement of the above-mentioned Sham lens disclosed in the present invention, the first lens is a biconcave lens, the second lens is a biconvex lens, the third lens is a convex-concave lens, the fourth lens is a convex-concave lens, the fifth lens is a biconcave lens, the sixth lens is a biconvex lens, the seventh lens is a plano-convex lens, the eighth lens is a concave-convex lens, and the ninth lens is a convex-concave lens.

[0013] As an improvement of the above-mentioned Sham lens disclosed in the present invention, the Sham lens further includes an aperture stop arranged between the fourth lens and the fifth lens, and the fifth lens and the sixth lens are cemented lenses.

[0014] As an improvement of the above-mentioned Sham lens disclosed in the present invention, the outer diameter D4 of the fourth lens and the diameter Dfno of the aperture stop satisfy 1.1<D4 / Dfno<1.7, and the aperture stop diameter Dfno and the outer diameter D5 of the fifth lens satisfy 0.4<Dfno / D5<0.7.

[0015] As an improvement to the above-mentioned Sham lens disclosed in the present invention, the air spacing d1 between the first lens and the second lens along the axial direction is 5 mm to 7 mm; the air spacing d2 between the second lens and the third lens along the axial direction is 0 mm to 2 mm; the air spacing d3 between the third lens and the fourth lens along the axial direction is 0 mm to 2 mm; the air spacing d4 between the fourth lens and the aperture stop along the axial direction is 1 mm to 3 mm; the air spacing d5 between the aperture stop and the fifth lens along the axial direction is 9 mm to 11 mm; the air spacing d6 between the sixth lens and the seventh lens along the axial direction is 0 mm to 2 mm; the air spacing d7 between the seventh lens and the eighth lens along the axial direction is 0 mm to 2 mm; and the air spacing d8 between the eighth lens and the ninth lens along the axial direction is 0 mm to 2 mm.

[0016] As an improvement of the above-mentioned Sham lens disclosed in the present invention, the curvature radius R11 of the incident surface of the first lens is -40mm to -30mm, and the curvature radius R12 of the exit surface is 30mm to 40mm; the curvature radius R21 of the incident surface of the second lens is 80mm to 90mm, and the curvature radius R22 of the exit surface is -40mm to -30mm; the curvature radius R31 of the incident surface of the third lens is 10mm to 20mm, and the curvature radius R32 of the exit surface is 55mm to 65mm; the curvature radius R41 of the incident surface of the fourth lens is 10mm to 20mm, and the curvature radius R42 of the exit surface is 5mm to 15mm; the curvature radius R51 of the incident surface of the fifth lens is 10mm to 20mm, and the curvature radius R52 of the exit surface is 5mm to 15mm. The angle of curvature of the incident surface of the sixth lens is -15mm~-5mm, and the radius of curvature R52 of the exit surface is 40mm~50mm; the radius of curvature R61 of the incident surface of the sixth lens is 40mm~50mm, and the radius of curvature R62 of the exit surface is -25mm~-15mm; the radius of curvature R71 of the incident surface of the seventh lens is infinite, and the radius of curvature R72 of the exit surface is -45mm~-35mm; the radius of curvature R81 of the incident surface of the eighth lens is -415mm~-405mm, and the radius of curvature R82 of the exit surface is -50mm~-40mm; the radius of curvature R91 of the incident surface of the ninth lens is 20mm~30mm, and the radius of curvature R92 of the exit surface is 70mm~80mm.

[0017] As an improvement to the above-mentioned Sham lens disclosed in the present invention, the center thickness CT1 of the first lens is 1 mm to 4 mm; the center thickness CT2 of the second lens is 2 mm to 5 mm; the center thickness CT3 of the third lens is 2 mm to 5 mm; the center thickness CT4 of the fourth lens is 1 mm to 4 mm; the center thickness CT5 of the fifth lens is 1 mm to 4 mm; the center thickness CT6 of the sixth lens is 6 mm to 9 mm; the center thickness CT7 of the seventh lens is 4 mm to 7 mm; the center thickness CT8 of the eighth lens is 4 mm to 7 mm; and the center thickness CT9 of the ninth lens is 4 mm to 7 mm.

[0018] As an improvement to the above-mentioned Sham lens disclosed in the present invention, the focal length f1 of the first lens is -30mm to -20mm; the focal length f2 of the second lens is 30mm to 40mm; the focal length f3 of the third lens is 25mm to 35mm; the focal length f4 of the fourth lens is -60mm to -50mm; the focal length f5 of the fifth lens is -20mm to -10mm; the focal length f6 of the sixth lens is 20mm to 30mm; the focal length f7 of the seventh lens is 50mm to 60mm; the focal length f8 of the eighth lens is 60mm to 70mm; and the focal length f9 of the ninth lens is 40mm to 50mm.

[0019] As an improvement of the above-mentioned Sham lens disclosed in the present invention, the refractive index N1 of the first lens is 1.6-1.7, and the Abbe number V1 is 30-35; the refractive index N2 of the second lens is 1.7-1.8, and the Abbe number V2 is 45-50; the refractive index N3 of the third lens is 1.7-1.8, and the Abbe number V3 is 35-40; the refractive index N4 of the fourth lens is 1.8-1.9, and the Abbe number V4 is 45-50; the refractive index N2 of the fifth lens is 1.7-1.8, and the Abbe number V3 is 45-50; The refractive index N5 of the sixth lens is 1.8-1.9, and the Abbe number V5 is 25-30; the refractive index N6 of the sixth lens is 1.6-1.7, and the Abbe number V6 is 55-60; the refractive index N7 of the seventh lens is 1.7-1.8, and the Abbe number V7 is 50-55; the refractive index N8 of the eighth lens is 1.7-1.8, and the Abbe number V8 is 50-55; the refractive index N9 of the ninth lens is 1.8-1.9, and the Abbe number V9 is 45-50.

[0020] As an improvement to the above-mentioned Sham lens disclosed in the present invention, the outer diameter D1 of the first lens is 20 mm to 24 mm, the outer diameter D2 of the second lens is 20 mm to 24 mm; the outer diameter D3 of the third lens is 18 mm to 22 mm; the outer diameter D4 of the fourth lens is 14 mm to 18 mm; the outer diameter D5 of the fifth lens is 20 mm to 24 mm; the outer diameter D6 of the sixth lens is 23 mm to 27 mm; the outer diameter D7 of the seventh lens is 30 mm to 34 mm; the outer diameter D8 of the eighth lens is 33 mm to 37 mm; and the outer diameter D9 of the ninth lens is 33 mm to 37 mm.

[0021] As an improvement to the above-mentioned Sham lens disclosed herein, the focal length f of the Sham lens is 17 mm to 50 mm; the aperture number of the Sham lens is F1.2 to F2.0; the field of view FOV of the Sham lens is 200 mm to 550 mm; the working distance WD of the Sham lens is 230 mm to 580 mm; the working wavelength band WL of the Sham lens is 390 nm to 480 nm; and the MTF@60 lp / mm of each field of view of the Sham lens is greater than 0.48.

[0022] As an improvement of the above-mentioned Sham lens disclosed in the present invention, the field of view FOV of the Sham lens and the working distance WD of the Sham lens satisfy 0.3<FOV / WD<2.5.

[0023] As an improvement of the above-mentioned Sham lens disclosed in the present invention, the aperture number of the Sham lens is F1.7 to F1.9.

[0024] As an improvement to the above-mentioned Sham lens disclosed in the present invention, the focal length f10 of the first lens group and the focal length f of the Sham lens satisfy 0.3<f10 / f<2.4; the focal length f20 of the second lens group and the focal length f of the Sham lens satisfy 0.2<|f20 / f|<2.1; the focal length f30 of the third lens group and the focal length f of the Sham lens satisfy 0.1<f30 / f<1.8.

[0025] As an improvement to the above-mentioned Sham lens disclosed herein, the first lens, the second lens, the third lens, and the fourth lens form a first lens group, and the focal length f10 of the first lens group is 20 mm to 40 mm; the fifth lens and the sixth lens form a second lens group, and the focal length f20 of the second lens group is -35 mm to -15 mm; the seventh lens, the eighth lens, and the ninth lens form a third lens group, and the focal length f30 of the third lens group is 10 mm to 30 mm; the axial distance d12 between the first lens group and the second lens group is 9 mm to 15 m; and the axial distance d23 between the second lens group and the third lens group is 0 mm to 3 mm.

[0026] A second aspect of the present disclosure provides an electronic device, comprising an image sensor and the Sham lens described in the first aspect, wherein the Sham lens is used to image a target on the image sensor; a target surface diagonal size IMG of the image sensor is 16 mm to 25 mm.

[0027] As an improvement to the electronic device disclosed herein, the target surface diagonal size IMG of the image sensor is 20 mm to 25 mm.

[0028] As an improvement to the electronic device disclosed above, the target surface diagonal size IMG of the image sensor and the field of view FOV of the Sham lens satisfy 0.02<IMG / FOV<0.15.

[0029] As an improvement to the above-mentioned electronic device disclosed in the present invention, the electronic device is a camera.

[0030] The electronic device provided in the second aspect of the present disclosure includes the Sham lens described in the first aspect, so the electronic device provided in the second aspect of the present disclosure also has the same advantages as the Sham lens described in the first aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The above and / or additional aspects and advantages of the present disclosure will become apparent and readily understood from the description of the embodiments with reference to the following drawings, in which:

[0032] Figure 1 is a diagram showing the principle of Sham's law;

[0033] FIG2 is a schematic structural diagram of a Sham lens provided in an embodiment of the present disclosure;

[0034] FIG3 is an optical path diagram of a Sham lens provided in an embodiment of the present disclosure;

[0035] FIG4 is an MTF curve diagram of a Sham lens provided by an embodiment of the present disclosure;

[0036] FIG5 is an MTF curve diagram of the Sham lens provided in Example 1 of the present disclosure;

[0037] FIG6 is an MTF curve diagram of the Sham lens provided in Example 2 of the present disclosure;

[0038] FIG7 is an MTF curve diagram of the Sham lens provided in Example 3 of the present disclosure. Modes for Carrying Out the Invention

[0039] A Sham lens utilizes Sham's law to generate images. According to Sham's law, as shown in Figure 1, when the extended lines of the target plane, the lens's main surface, and the detector plane intersect, the entire tilted target field of view can be clearly imaged. The angle of the optical path must satisfy the following relationship: α is the angle between the target plane and the lens's optical axis, β is the angle between the detector plane and the lens's optical axis, f' is the focal length of the lens, l is the object distance at point D on the optical axis, l' is the image distance at point D on the optical axis, and l' / l is the lens's magnification.

[0040]

[0041] In some practical applications, the measurement area is large, requiring a Sham lens with a wide field of view and adaptability to camera chips with large target surfaces. However, when a Sham lens is directly applied to a camera, the lens optical axis is no longer perpendicular to the camera chip surface. When the cover glass on the chip surface is parallel to the chip surface, the cover glass is no longer perpendicular to the lens optical axis and becomes off-axis, causing spherical aberration, coma, and astigmatism in the imaging system, resulting in insufficient clarity at the edges of the image. Achieving clear, full-frame imaging with a wide field of view makes it possible for Sham lenses to be used in rapid detection applications and has become a key research area for Sham lenses.

[0042] In view of this, the embodiments of the present disclosure provide a Sham lens having the characteristics of a large field of view, a large target surface, and strong light-receiving capability. The MTF of the lens at all locations across the full frame meets the camera's Nylon requirements, and the full frame provides clear imaging, making it possible to use the Sham lens in measurement applications with high speed requirements and a large field of view.

[0043] The following describes in detail embodiments of the present disclosure, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present disclosure, and should not be construed as limiting the present disclosure.

[0044] FIG2 is a schematic diagram of the structure of a Sham lens provided in an embodiment of the present disclosure.

[0045] 2 , the Sham lens of the disclosed embodiment includes a plurality of lenses coaxially arranged in sequence from the object side to the image side, with the outer diameter of the lens closest to the object side being smaller than the outer diameter of the lens closest to the image side. In this way, the Sham lens forms an optical path structure with a smaller front and a larger back, effectively increasing the light receiving capacity of the lens and providing the possibility for application in high-speed measurement.

[0046] In some embodiments, the outer diameter D1 of the lens closest to the object side and the outer diameter D9 of the lens closest to the image side satisfy 0.3<D1 / D9<0.8.

[0047] Furthermore, in the Sham lens of the embodiment of the present disclosure, the incident surface of the lens closest to the object side is a concave surface; the exit surface of the lens closest to the image side is a concave surface, so that imaging of a large field of view and a large target surface can be achieved while ensuring the limitations of the overall external dimensions of the lens.

[0048] The Sham lens of the disclosed embodiment forms an optical path architecture with a small front and a large rear, so that the front aperture of the lens is smaller, which is conducive to ensuring the small size and volume of the lens; by setting the incident surface of the lens closest to the object side as a concave surface, it can absorb light within a wide range and a large angle, thereby improving the field of view of the lens; by setting the exit surface of the lens closest to the image side as a concave surface, the light is scattered and imaged on the image sensor with a large target surface at the rear. The image sensor with a large target surface can provide larger pixels, thereby providing the possibility of applying the Sham lens to precision recognition.

[0049] The Sham lens of the disclosed embodiment includes a first lens group 1, a second lens group 2, and a third lens group 3, which are coaxially arranged from the object side to the image side. Each of the first lens group 1, the second lens group 2, and the third lens group 3 is composed of at least one lens, which may include a doublet of a separated lens or a cemented lens. These lenses may all be spherical lenses, all aspherical lenses, or a combination of spherical and aspherical lenses.

[0050] The Sham lens of the disclosed embodiments can be made of colorless optical glass or optical plastic. Optical plastic offers low cost in mass production, easy processing of aspheric surfaces, and lightweight. Optical glass possesses stable mechanical and thermal properties, and by combining different refractive indices and Abbe numbers, it can eliminate chromatic aberration and improve image quality. Industrial robots are used in diverse environments, and the lenses of Sham lenses must maintain high ambient temperature stability.

[0051] Among them, the outer diameter of the lens closest to the object side in the first lens group 1 is smaller than the outer diameter of the lens closest to the image side in the third lens group 3; the incident surface of the lens closest to the object side in the first lens group 1 is concave, and the exit surface of the lens closest to the image side in the third lens group 3 is concave.

[0052] Table 1 Parameters of Sham lens

[0053]

[0054] Table 1 above introduces the overall performance parameters of the Sham lens. The performance parameters broken down into three lens groups are shown in Table 2. The axial spacing in Table 2 refers to the spacing along the optical axis.

[0055] Table 2 Parameters of each lens group of the Sham lens

[0056]

[0057] The axial spacing between two lens groups refers to the axial spacing along the optical axis between the two closest lenses in two adjacent lens groups. The axial spacing d12 between the first lens group 1 and the second lens group 2 is 10mm to 13mm. This means that the spacing along the optical axis between the center of the exit surface of the lens closest to the second lens group 2 in the first lens group 1 and the center of the incident surface of the lens closest to the first lens group 1 in the second lens group 2 is 9mm to 15mm. In conjunction with the following description of each lens, the axial spacing d12 between the first lens group 1 and the second lens group 2 refers to the spacing along the optical axis between the center of the exit surface of the fourth lens G4 and the center of the incident surface of the fifth lens G5.

[0058] The axial spacing d23 between the second lens group 2 and the third lens group 3 is 0 mm to 3 mm. This means that the distance along the optical axis between the center of the exit surface of the lens element in the second lens group 2 closest to the third lens group 3 and the center of the entrance surface of the lens element in the third lens group 3 closest to the second lens group 2 is 0 mm to 3 mm. In conjunction with the following description of the individual lenses, the axial spacing d23 between the second lens group 2 and the third lens group 3 refers to the distance along the optical axis between the center of the exit surface of the sixth lens element G6 and the center of the entrance surface of the seventh lens element G7.

[0059] In some possible implementations, the focal length f10 of the first lens group and the focal length f of the Sham lens satisfy 0.3<f10 / f<2.4; the focal length f20 of the second lens group and the focal length f of the Sham lens satisfy 0.2<|f20 / f|<2.1; the focal length f30 of the third lens group and the focal length f of the Sham lens satisfy 0.1<f30 / f<1.8.

[0060] The above describes the overall performance of the Sham lens according to the embodiment of the present disclosure. The following further introduces the performance parameters of each lens through examples.

[0061] In some implementations, referring to Figure 2 , a Sham lens includes a first lens G1, a second lens G2, a third lens G3, a fourth lens G4, a fifth lens G5, a sixth lens G6, a seventh lens G7, an eighth lens G8, and a ninth lens G9, arranged coaxially from the object side to the image side. First lens G1 is the lens closest to the object side, and ninth lens G9 is the lens closest to the image side. As such, the outer diameter D1 of first lens G1 is smaller than the outer diameter D2 of ninth lens G9, and the entrance surface of first lens G1 and the exit surface of ninth lens G9 are both concave.

[0062] It should be noted here that light passes through the Sham lens from the object side to the image side, and the side of each lens facing the object side is the incident surface, and the side of each lens facing the image side is the exit surface.

[0063] In some embodiments, the first lens G1 is a biconcave lens, the second lens G2 is a biconvex lens, the third lens G3 is a convex-concave lens, the fourth lens G4 is a convex-concave lens, the fifth lens G5 is a biconcave lens, the sixth lens G6 is a biconvex lens, the seventh lens G7 is a plano-convex lens, the eighth lens G8 is a concave-convex lens, and the ninth lens G9 is a convex-concave lens.

[0064] Continuing with Figure 2, the Sham lens of the disclosed embodiment also includes an aperture stop 10 disposed between the fourth lens element G4 and the fifth lens element G5. The fifth lens element G5 and the sixth lens element G6 are cemented lenses. The exit surface of the fourth lens element G4 before the aperture stop 10 is concave, and the entrance surface of the fifth lens element G5 is concave. Both of these concave surfaces cause light to diverge, resulting in large refraction angles. This can easily cause astigmatism and field curvature, particularly in the peripheral areas, which can affect image quality. The disclosed embodiment utilizes a cemented lens after the aperture stop 10 to optimize the large refraction angles caused by the two concave surfaces and the large aperture stop 10. The convex surface of the sixth lens element G6 converges light, thereby reducing astigmatism and field curvature caused by the tilted arrangement of the chip cover glass in the Sham lens optical path, thereby improving image clarity.

[0065] The relationship between the outer diameter D4 of the fourth lens G4 and the diameter Dfno of the aperture stop 10 satisfies 1.1<D4 / Dfno<1.7, and the relationship between the diameter Dfno of the aperture stop 10 and the outer diameter D5 of the fifth lens G5 satisfies 0.4<Dfno / D5<0.7.

[0066] The Sham lens of the disclosed embodiment operates in the low-wavelength band (WL) of 390nm to 480nm, requiring specialized treatment of chromatic aberration. By using a cemented lens to offset chromatic aberration caused by the lens's inherent properties, the lens can be more effectively used in the short-wavelength band. Example 1

[0067] The axial air spacing d1 between the first lens G1 and the second lens G2 is 5 mm to 7 mm; the axial air spacing d2 between the second lens G2 and the third lens G3 is 0 mm to 2 mm; the axial air spacing d3 between the third lens G3 and the fourth lens G4 is 0 mm to 2 mm; the axial spacing d4 between the fourth lens G4 and the aperture stop 10 is 1 mm to 3 mm; the axial spacing d5 between the aperture stop 10 and the fifth lens G5 is 9 mm to 11 mm; the axial air spacing d6 between the sixth lens G6 and the seventh lens G7 is 0 mm to 2 mm; the axial air spacing d7 between the seventh lens G7 and the eighth lens G8 is 0 mm to 2 mm; and the axial air spacing d8 between the eighth lens G8 and the ninth lens G9 is 0 mm to 2 mm. In the disclosed embodiments, the axial direction refers to the direction along the optical axis.

[0068] The curvature radius R11 of the incident surface of the first lens G1 is -40mm to -30mm, and the curvature radius R12 of the exit surface is 30mm to 40mm; the curvature radius R21 of the incident surface of the second lens G2 is 80mm to 90mm, and the curvature radius R22 of the exit surface is -40mm to -30mm; the curvature radius R31 of the incident surface of the third lens G3 is 10mm to 20mm, and the curvature radius R32 of the exit surface is 55mm to 65mm; the curvature radius R41 of the incident surface of the fourth lens G4 is 10mm to 20mm, and the curvature radius R42 of the exit surface is 5mm to 15mm; the curvature radius R51 of the incident surface of the fifth lens G5 is -15mm to -5mm, and the curvature radius R The radius of curvature R52 of the incident surface of the sixth lens G6 is 40mm-50mm; the radius of curvature R61 of the incident surface of the sixth lens G6 is 40mm-50mm, and the radius of curvature R62 of the exit surface is -25mm--15mm; the radius of curvature R71 of the incident surface of the seventh lens G7 is infinite, that is, the incident surface of the seventh lens G7 is a plane; the radius of curvature R72 of the exit surface of the seventh lens G7 is -45mm--35mm; the radius of curvature R81 of the incident surface of the eighth lens G8 is -415mm--405mm, and the radius of curvature R82 of the exit surface is -50mm--40mm; the radius of curvature R91 of the incident surface of the ninth lens G9 is 20mm-30mm, and the radius of curvature R92 of the exit surface is 70mm-80mm.

[0069] The center thickness CT1 of the first lens G1 is 1 mm to 4 mm; the center thickness CT2 of the second lens G2 is 2 mm to 5 mm; the center thickness CT3 of the third lens G3 is 2 mm to 5 mm; the center thickness CT4 of the fourth lens G4 is 1 mm to 4 mm; the center thickness CT5 of the fifth lens G5 is 1 mm to 4 mm; the center thickness CT6 of the sixth lens G6 is 6 mm to 9 mm; the center thickness CT7 of the seventh lens G7 is 4 mm to 7 mm; the center thickness CT8 of the eighth lens G8 is 4 mm to 7 mm; and the center thickness CT9 of the ninth lens G9 is 4 mm to 7 mm. In the disclosed embodiments, the center thickness refers to the thickness of the center of the lens along the optical axis.

[0070] The focal length f1 of the first lens G1 is -30 mm to -20 mm; the focal length f2 of the second lens G2 is 30 mm to 40 mm; the focal length f3 of the third lens G3 is 25 mm to 35 mm; the focal length f4 of the fourth lens G4 is -60 mm to -50 mm; the focal length f5 of the fifth lens G5 is -20 mm to -10 mm; the focal length f6 of the sixth lens G6 is 20 mm to 30 mm; the focal length f7 of the seventh lens G7 is 50 mm to 60 mm; the focal length f8 of the eighth lens G8 is 60 mm to 70 mm; and the focal length f9 of the ninth lens G9 is 40 mm to 50 mm.

[0071] The refractive index N1 of the first lens G1 is 1.6-1.7, and the Abbe number V1 is 30-35; the refractive index N2 of the second lens G2 is 1.7-1.8, and the Abbe number V2 is 45-50; the refractive index N3 of the third lens G3 is 1.7-1.8, and the Abbe number V3 is 35-40; the refractive index N4 of the fourth lens G4 is 1.8-1.9, and the Abbe number V4 is 45-50; the refractive index N5 of the fifth lens G5 is 1.8 The refractive index N6 of the sixth lens element G6 is 1.6-1.7, and the Abbe number V6 is 55-60; the refractive index N7 of the seventh lens element G7 is 1.7-1.8, and the Abbe number V7 is 50-55; the refractive index N8 of the eighth lens element G8 is 1.7-1.8, and the Abbe number V8 is 50-55; the refractive index N9 of the ninth lens element G9 is 1.8-1.9, and the Abbe number V9 is 45-50. The disclosed embodiments define the material properties of each lens by limiting the refractive index and Abbe number of each lens.

[0072] The outer diameter D1 of the first lens G1 is 20 mm to 24 mm, the outer diameter D2 of the second lens G2 is 20 mm to 24 mm; the outer diameter D3 of the third lens G3 is 18 mm to 22 mm; the outer diameter D4 of the fourth lens G4 is 14 mm to 18 mm; the outer diameter D5 of the fifth lens G5 is 20 mm to 24 mm; the outer diameter D6 of the sixth lens G6 is 23 mm to 27 mm; the outer diameter D7 of the seventh lens G7 is 30 mm to 34 mm; the outer diameter D8 of the eighth lens G8 is 33 mm to 37 mm; and the outer diameter D9 of the ninth lens G9 is 33 mm to 37 mm.

[0073] The parameters of each lens in this embodiment can be calculated using optical design software or through a ray tracing algorithm, but the present disclosure does not limit the design tools and design process.

[0074] By individually limiting the radius of curvature, center thickness, air spacing, focal length, refractive index, and Abbe number of the nine lenses, the disclosed embodiment achieves a focal length f of 17mm to 50mm. The aperture of the Sham lens ranges from F1.2 to F2.0. Compared to the conventional F4 aperture, the Sham lens of the disclosed embodiment has a smaller aperture and a larger diaphragm, allowing for more light and improving measurement speed when used in cameras. The Sham lens has a field of view (FOV) of 200mm to 550mm, a working distance (WD) of 230mm to 580mm, and an operating wavelength (WL) of 390nm to 480nm.

[0075] In some embodiments, the aperture number of the Sham lens is F1.7 to F1.9.

[0076] In some embodiments, the field of view FOV of the Sham lens and the working distance WD of the Sham lens satisfy 0.3<FOV / WD<2.5.

[0077] The Sham lens provided in the present disclosure is compatible with an image sensor having a target surface diagonal size IMG of 16 mm to 25 mm. In some embodiments, the compatible image sensor has a target surface diagonal size IMG of 20 mm to 25 mm. The camera's Nyquist frequency is 60 lp / mm.

[0078] FIG3 is an optical path diagram of a Sham lens provided in an embodiment of the present disclosure; FIG4 is an MTF curve diagram of a Sham lens provided in an embodiment of the present disclosure.

[0079] With reference to Figure 3 , the field of view (FOV) of the Sham lens 100 disclosed herein ranges from 200mm to 550mm, making it compatible with an image sensor 200 having a target surface diagonal dimension (IMG) of 16mm to 25mm. The working distance (WD) of the Sham lens ranges from 230mm to 580mm. As can be seen from Figure 3 , while maintaining the required optical path size and volume of the lens, it can achieve full-frame, clear imaging for a field of view equivalent to the working distance.

[0080] In some embodiments, the target surface diagonal size IMG of the image sensor and the field of view FOV of the Sham lens satisfy 0.02<IMG / FOV<0.15.

[0081] In Figure 4, the horizontal axis represents spatial frequency in line pairs per millimeter (lp / mm), and the vertical axis represents contrast, ranging from 0 to 1. The solid and dashed lines represent the meridional and sagittal components of the MTF at different fields of view. The solid line represents the contrast component in the meridional direction, which is perpendicular to the optical axis; the dashed line represents the contrast component in the sagittal direction, which is along the optical axis. The larger the vertical axis value of the two curves and the closer the two curves are, the higher the image clarity. As shown in Figure 4, the design MTF values ​​for each field of view are greater than 0.48 at a spatial frequency of 60 lp / mm, meeting the camera's Nyquist frequency requirement. Furthermore, compared to the conventional MTF @ 60 lp / mm with a contrast ratio of 0.3, the Sham lens of the present disclosure has a higher contrast at 60 lp / mm, resulting in clearer images.

[0082] Therefore, the Sham lens of the disclosed embodiment has high light-receiving capability, can clearly image targets with a large field of view, and can effectively utilize a large-target-area camera to improve resolution. Example 2

[0083] In some embodiments, the working distance of the Sham lens is 260 mm to 355 mm, the aperture of the Sham lens is F1.7 to F1.9, the diagonal target surface size IMG of the image sensor is 15 mm to 21 mm, the focal length f is 17 mm to 23 mm, the operating wavelength is 390 nm to 480 nm, the angle between the target plane and the lens optical axis is 19°, and the system paraxial magnification is -0.061X.

[0084] The focal length f10 of the first lens group 1 is 23.5 mm to 31.9 mm; the focal length f20 of the second lens group 2 is -30.1 mm to -22.2 mm; and the focal length f30 of the third lens group 3 is 13.7 mm to 18.6 mm.

[0085] The radius of curvature R11 of the incident surface of the first lens G1 is -38.2mm to -28.2mm, and the radius of curvature R12 of the exit surface is 29.3mm to 39.7mm; the radius of curvature R21 of the incident surface of the second lens G2 is 63.5mm to 86.0mm, and the radius of curvature R22 of the exit surface is -39.3mm to -29.0mm; the radius of curvature R31 of the incident surface of the third lens G3 is 12.9mm to 17.6mm, and the radius of curvature R32 of the exit surface is 47.1mm to 63.8mm; the radius of curvature R41 of the incident surface of the fourth lens G4 is 11.7mm to 15.9mm, and the radius of curvature R42 of the exit surface is 8.1mm to 11.1mm; the radius of curvature R51 of the incident surface of the fifth lens G5 is -10.2mm to - The radius of curvature R52 of the exit surface is 35.1mm~47.6mm; the radius of curvature R61 of the incident surface of the sixth lens G6 is 35.1mm~47.6mm, and the radius of curvature R62 of the exit surface is -20.0mm~-14.7mm; the radius of curvature R71 of the incident surface of the seventh lens G7 is infinite, and the radius of curvature R72 of the exit surface is -43.6mm~-32.2mm; the radius of curvature R81 of the incident surface of the eighth lens G8 is -428.7mm~-316.7mm, and the radius of curvature R82 of the exit surface is -44mm~-32.5mm; the radius of curvature R91 of the incident surface of the ninth lens G9 is 19.6mm~26.6mm, and the radius of curvature R92 of the exit surface is 58.0mm~78.6mm.

[0086] The center thickness GT1 of the first lens G1 is 1.5 mm to 2.2 mm; the center thickness GT2 of the second lens G2 is 3.1 mm to 4.3 mm; the center thickness GT3 of the third lens G3 is 3.2 mm to 4.5 mm; the center thickness GT4 of the fourth lens G4 is 2.1 mm to 2.9 mm; the center thickness GT5 of the fifth lens G5 is 1.6 mm to 2.3 mm; the center thickness GT6 of the sixth lens G6 is 6.4 mm to 8.7 mm; the center thickness GT7 of the seventh lens G7 is 4.0 mm to 5.5 mm; the center thickness GT8 of the eighth lens G8 is 4.1 mm to 5.7 mm; and the center thickness GT9 of the ninth lens G9 is 5.2 mm to 7.1 mm.

[0087] The air gap d1 between the first lens G1 and the second lens G2 along the optical axis is 4.5 mm to 6.2 mm; the air gap d2 between the second lens G2 and the third lens G3 along the optical axis is 0.07 mm to 0.11 mm; the air gap d3 between the third lens G3 and the fourth lens G4 along the optical axis is 0.07 mm to 0.11 mm; the air gap d4 between the fourth lens G4 and the aperture stop 10 along the optical axis is 1.4 mm to 2.1 mm; and the air gap d5 between the aperture stop 10 and the fifth lens G5 along the optical axis is 7.5 mm. The fifth lens G5 and the sixth lens G6 are cemented lenses; the air distance d6 between the sixth lens G6 and the seventh lens G7 along the optical axis is 0.07 mm to 0.11 mm; the air distance d7 between the seventh lens G7 and the eighth lens G8 along the optical axis is 0.07 mm to 0.11 mm; the air distance d8 between the eighth lens G8 and the ninth lens G9 along the optical axis is 0.07 mm to 0.11 mm; and the air distance BFL between the ninth lens G9 and the image plane along the optical axis is 9.4 mm to 12.9 mm.

[0088] The focal length f1 of the first lens G1 is -26.3 mm to -19.5 mm; the focal length f2 of the second lens G2 is 25.3 mm to 34.3 mm; the focal length f3 of the third lens G3 is 21.6 mm to 29.4 mm; the focal length f4 of the fourth lens G4 is -59.7 mm to -44.1 mm; the focal length f5 of the fifth lens G5 is -11.3 mm to -8.3 mm; the focal length f6 of the sixth lens G6 is 22.1 mm to 30.0 mm; the focal length f7 of the seventh lens G7 is 43.2 mm to 55.6 mm; the focal length f8 of the eighth lens G8 is 48.3 mm to 65.5 mm; and the focal length f9 of the ninth lens G9 is 33.0 mm to 44.7 mm.

[0089] The refractive index N1 of the first lens G1 is 1.65-1.7, and the Abbe number V1 is 31.0-31.5; the refractive index N2 of the second lens G2 is 1.75-1.8, and the Abbe number V2 is 49.5-50; the refractive index N3 of the third lens G3 is 1.73-1.78, and the Abbe number V3 is 37.3-37.8; the refractive index N4 of the fourth lens G4 is 1.8-1.85, and the Abbe number V4 is 46.3-46.8; the refractive index N5 of the fifth lens G5 is 1.78-1 .83, and its Abbe number V5 is 25.3-25.8; the refractive index N6 of the sixth lens element G6 is 1.67-1.72, and its Abbe number V6 is 55.3-55.8; the refractive index N7 of the seventh lens element G7 is 1.70-1.75, and its Abbe number V7 is 50-50.5; the refractive index N8 of the eighth lens element G8 is 1.7-1.75, and its Abbe number V8 is 50-50.5; the refractive index N9 of the ninth lens element G9 is 1.8-1.85, and its Abbe number V9 is 46.3-46.8.

[0090] Example 1

[0091] In this example, the Sham lens has a working distance of 278mm, an aperture of F1.8, an image sensor target surface diagonal dimension IMG of 16mm, a focal length f of 18mm, and an operating wavelength range of 390nm to 480nm. The angle between the target plane and the lens optical axis is 19°, and the system's paraxial magnification is -0.061X.

[0092] The focal length f10 of the first lens group 1 is 24.92 mm, the focal length f20 of the second lens group 2 is -23.53 mm, and the focal length f30 of the third lens group 3 is 14.53 mm.

[0093] The curvature radius of each lens is as follows: the curvature radius R11 of the incident surface of the first lens G1 is -29.95mm, and the curvature radius R12 of the exit surface is 31.01mm; the curvature radius R21 of the incident surface of the second lens G2 is 67.25mm, and the curvature radius R22 of the exit surface is -30.76mm; the curvature radius 31 of the incident surface of the third lens G3 is 13.71mm, and the curvature radius R32 of the exit surface is 49.89mm; the curvature radius R41 of the incident surface of the fourth lens G4 is 12.44mm, and the curvature radius R42 of the exit surface is 8.67mm; the curvature radius R51 of the incident surface of the fifth lens G5 is 10. The radius of curvature R52 of the incident surface of the sixth lens G6 is -7.91mm, and the radius of curvature R61 of the exit surface is 37.18mm; the radius of curvature R61 of the incident surface of the sixth lens G6 is 37.18mm, and the radius of curvature R62 of the exit surface is -15.65mm; the radius of curvature R71 of the incident surface of the seventh lens G7 is infinite, and the radius of curvature R72 of the exit surface is -34.11mm; the radius of curvature R81 of the incident surface of the eighth lens G8 is -335.41mm, and the radius of curvature R82 of the exit surface is -34.43mm; the radius of curvature R91 of the incident surface of the ninth lens G9 is 20.79mm, and the radius of curvature R92 of the exit surface is 61.46mm.

[0094] The center thickness GT1 of the first lens G1 is 1.67 mm; the center thickness GT2 of the second lens G2 is 3.30 mm; the center thickness GT3 of the third lens G3 is 3.45 mm; the center thickness GT4 of the fourth lens G4 is 2.26 mm; the center thickness GT5 of the fifth lens G5 is 1.75 mm; the center thickness GT6 of the sixth lens G6 is 6.78 mm; the center thickness GT7 of the seventh lens G7 is 4.28 mm; the center thickness GT8 of the eighth lens G8 is 4.44 mm; and the center thickness GT9 of the ninth lens G9 is 5.52 mm.

[0095] The air distance d1 along the optical axis between the first lens G1 and the second lens G2 is 4.81 mm; the air distance d2 along the optical axis between the second lens G2 and the third lens G3 is 0.08 mm; the air distance d3 along the optical axis between the third lens G3 and the fourth lens G4 is 0.08 mm; the air distance d4 along the optical axis between the fourth lens G4 and the aperture stop 10 is 1.57 mm; the air distance d5 along the optical axis between the aperture stop 10 and the fifth lens G5 is 8.05 mm; the fifth lens G5 and the sixth lens G6 are a cemented lens; the air distance d6 along the optical axis between the sixth lens G6 and the seventh lens G7 is 0.08 mm; the air distance d7 along the optical axis between the seventh lens G7 and the eighth lens G8 is 0.08 mm; the air distance d8 along the optical axis between the eighth lens G8 and the ninth lens G9 is 0.08 mm; and the air distance BFL along the optical axis between the ninth lens G9 and the image plane is 10.05 mm.

[0096] The focal length f1 of the first lens G1 is -20.65 mm; the focal length f2 of the second lens G2 is 26.82 mm; the focal length f3 of the third lens G3 is 22.97 mm; the focal length f4 of the fourth lens G4 is -46.72 mm; the focal length f5 of the fifth lens G5 is -8.80 mm; the focal length f6 of the sixth lens G6 is 23.45 mm; the focal length f7 of the seventh lens G7 is 45.81 mm; the focal length f8 of the eighth lens G8 is 51.22 mm; and the focal length f9 of the ninth lens G9 is 34.94 mm.

[0097] The refractive index N1 of the first lens element G1 is 1.69, and the Abbe number V1 is 31.2; the refractive index N2 of the second lens element G2 is 1.77, and the Abbe number V2 is 49.6; the refractive index N3 of the third lens element G3 is 1.75, and the Abbe number V3 is 37.5; the refractive index N4 of the fourth lens element G4 is 1.82, and the Abbe number V4 is 46.6; the refractive index N5 of the fifth lens element G5 is 1.81, and the Abbe number V5 is 25.5; the refractive index N6 of the sixth lens element G6 is 1.70, and the Abbe number V6 is 55.5; the refractive index N7 of the seventh lens element G7 is 1.72, and the Abbe number V7 is 50.3; the refractive index N8 of the eighth lens element G8 is 1.72, and the Abbe number V8 is 50.3; and the refractive index N9 of the ninth lens element G9 is 1.82, and the Abbe number V9 is 46.6.

[0098] As shown in Figure 5, the MTF design values ​​for each field of view have a contrast ratio greater than 0.48 at a spatial frequency of 60 lp / mm, which meets the Nyquist frequency requirement of the camera, resulting in higher contrast and clearer imaging.

[0099] Example 2

[0100] In this example, the Sham lens has a working distance of 309mm, an aperture of F1.8, an image sensor target surface diagonal dimension IMG of 18mm, a focal length f of 20mm, and an operating wavelength range of 390nm to 480nm. The angle between the target plane and the lens optical axis is 19°, and the system's paraxial magnification is -0.061X.

[0101] The focal length f10 of the first lens group 1 is 27.69 mm, the focal length f20 of the second lens group 2 is -26.18 mm, and the focal length f30 of the third lens group 3 is 16.15 mm.

[0102] The curvature radius of each lens is as follows: the curvature radius R11 of the incident surface of the first lens G1 is -33.28mm, and the curvature radius R12 of the exit surface is 34.46mm; the curvature radius R21 of the incident surface of the second lens G2 is 74.73mm, and the curvature radius R22 of the exit surface is -34.18mm; the curvature radius R31 of the incident surface of the third lens G3 is 15.23mm, and the curvature radius R32 of the exit surface is 55.44mm; the curvature radius R41 of the incident surface of the fourth lens G4 is 13.82mm, and the curvature radius R42 of the exit surface is 9.64mm; the curvature radius R5 of the incident surface of the fifth lens G5 is 13.82mm. The radius of curvature of the incident surface of the sixth lens element G6 is R61, which is 41.32 mm, and the radius of curvature of the exit surface is R62, which is -17.39 mm. The radius of curvature of the incident surface of the seventh lens element G7 is infinite, and the radius of curvature of the exit surface is R72, which is -37.90 mm. The radius of curvature of the incident surface of the eighth lens element G8 is R81, which is -372.70 mm, and the radius of curvature of the exit surface is R82, which is -38.26 mm. The radius of curvature of the incident surface of the ninth lens element G9 is R91, which is 23.10 mm, and the radius of curvature of the exit surface is R92, which is 68.29 mm.

[0103] The center thickness GT1 of the first lens G1 is 1.85 mm; the center thickness GT2 of the second lens G2 is 3.67 mm; the center thickness GT3 of the third lens G3 is 3.83 mm; the center thickness GT4 of the fourth lens G4 is 2.51 mm; the center thickness GT5 of the fifth lens G5 is 1.94 mm; the center thickness GT6 of the sixth lens G6 is 7.53 mm; the center thickness GT7 of the seventh lens G7 is 4.76 mm; the center thickness GT8 of the eighth lens G8 is 4.94 mm; and the center thickness GT9 of the ninth lens G9 is 6.14 mm.

[0104] The air distance d1 along the optical axis between the first lens G1 and the second lens G2 is 5.34 mm; the air distance d2 along the optical axis between the second lens G2 and the third lens G3 is 0.09 mm; the air distance d3 along the optical axis between the third lens G3 and the fourth lens G4 is 0.09 mm; the air distance d4 along the optical axis between the fourth lens G4 and the aperture stop 10 is 1.75 mm; the air distance d5 along the optical axis between the aperture stop 10 and the fifth lens G5 is 8.94 mm; the fifth lens G5 and the sixth lens G6 are a cemented lens; the air distance d6 along the optical axis between the sixth lens G6 and the seventh lens G7 is 0.09 mm; the air distance d7 along the optical axis between the seventh lens G7 and the eighth lens G8 is 0.09 mm; the air distance d8 along the optical axis between the eighth lens G8 and the ninth lens G9 is 0.09 mm; and the air distance BFL along the optical axis between the ninth lens G9 and the image plane is 11.16 mm.

[0105] The focal length f1 of the first lens G1 is -22.95 mm; the focal length f2 of the second lens G2 is 29.80 mm; the focal length f3 of the third lens G3 is 25.53 mm; the focal length f4 of the fourth lens G4 is -51.90 mm; the focal length f5 of the fifth lens G5 is -9.78 mm; the focal length f6 of the sixth lens G6 is 26.05 mm; the focal length f7 of the seventh lens G7 is 50.90 mm; the focal length f8 of the eighth lens G8 is 56.92 mm; and the focal length f9 of the ninth lens G9 is 38.83 mm.

[0106] The refractive index N1 of the first lens element G1 is 1.69, and the Abbe number V1 is 31.2; the refractive index N2 of the second lens element G2 is 1.77, and the Abbe number V2 is 49.6; the refractive index N3 of the third lens element G3 is 1.75, and the Abbe number V3 is 37.5; the refractive index N4 of the fourth lens element G4 is 1.82, and the Abbe number V4 is 46.6; the refractive index N5 of the fifth lens element G5 is 1.81, and the Abbe number V5 is 25.5; the refractive index N6 of the sixth lens element G6 is 1.70, and the Abbe number V6 is 55.5; the refractive index N7 of the seventh lens element G7 is 1.72, and the Abbe number V7 is 50.3; the refractive index N8 of the eighth lens element G8 is 1.72, and the Abbe number V8 is 50.3; and the refractive index N9 of the ninth lens element G9 is 1.82, and the Abbe number V9 is 46.6.

[0107] As shown in Figure 6, the MTF design values ​​for each field of view have a contrast ratio greater than 0.48 at a spatial frequency of 60 lp / mm, which meets the camera's Nyquist frequency requirement, resulting in higher contrast and clearer imaging. Example 3

[0108] In some embodiments, the working distance of the Sham lens is 336 mm to 343 mm, the aperture of the Sham lens is F1.7 to F1.9, the diagonal target surface size IMG of the image sensor is 19.2 mm to 19.6 mm, the focal length f is 21.7 mm to 22.3 mm, the operating wavelength is 390 nm to 480 nm, the angle between the target plane and the lens optical axis is 19°, and the system paraxial magnification is -0.061X.

[0109] The focal length f10 of the first lens group 1 is 30.1 mm to 30.5 mm, the focal length f20 of the second lens group 2 is -28.9 mm to -28.5 mm, and the focal length f30 of the third lens group 3 is 17.6 mm to 17.8 mm.

[0110] The curvature radius R11 of the incident surface of the first lens G1 is -37.0mm~-36.2mm, and the curvature radius R12 of the exit surface is 37.5mm~38.3mm; the curvature radius R21 of the incident surface of the second lens G2 is 81.4mm~83.0mm, and the curvature radius R22 of the exit surface is -38.0mm~-37.2mm; the curvature radius R31 of the incident surface of the third lens G3 is 16.6mm~17.0mm, and the curvature radius R32 of the exit surface is 60.4mm~61.6mm; the curvature radius R41 of the incident surface of the fourth lens G4 is 15.0mm~15.4mm, and the curvature radius R42 of the exit surface is 10.5mm~10.7mm; the curvature radius R51 of the incident surface of the fifth lens G5 is -9.8mm~-9. .5mm, and the radius of curvature R52 of the exit surface is 45.0mm~45.9mm; the radius of curvature R61 of the incident surface of the sixth lens G6 is 45.0mm~45.9mm, and the radius of curvature R62 of the exit surface is -19.4mm~-18.9mm; the radius of curvature R71 of the incident surface of the seventh lens G7 is infinite, and the radius of curvature R72 of the exit surface is -42.1mm~-41.3mm; the radius of curvature R81 of the incident surface of the eighth lens G8 is -413.7mm~-406.2mm, and the radius of curvature R82 of the exit surface is -42.5mm~-41.7mm; the radius of curvature R91 of the incident surface of the ninth lens G9 is 25.1mm~25.7mm, and the radius of curvature R92 of the exit surface is 74.4mm~75.9mm.

[0111] The center thickness GT1 of the first lens G1 is 2.0 mm to 2.1 mm; the center thickness GT2 of the second lens G2 is 3.9 mm to 4.1 mm; the center thickness GT3 of the third lens G3 is 4.1 mm to 4.3 mm; the center thickness GT4 of the fourth lens G4 is 2.7 mm to 2.8 mm; the center thickness GT5 of the fifth lens G5 is 2.1 mm to 2.2 mm; the center thickness GT6 of the sixth lens G6 is 8.2 mm to 8.4 mm; the center thickness GT7 of the seventh lens G7 is 5.1 mm to 5.3 mm; the center thickness GT8 of the eighth lens G8 is 5.3 mm to 5.5 mm; and the center thickness GT9 of the ninth lens G9 is 6.6 mm to 6.9 mm.

[0112] The air distance d1 between the first lens G1 and the second lens G2 along the optical axis is 5.8 mm to 6.0 mm; the air distance d2 between the second lens G2 and the third lens G3 along the optical axis is 0.09 mm to 0.11 mm; the air distance d3 between the third lens G3 and the fourth lens G4 along the optical axis is 0.09 mm to 0.11 mm; the air distance d4 between the fourth lens G4 and the aperture stop 10 along the optical axis is 1.9 mm to 2.0 mm; the air distance d5 between the aperture stop 10 and the fifth lens G5 along the optical axis is 9.7 mm. m~10.0mm; the fifth lens G5 and the sixth lens G6 are a cemented lens; the air distance d6 between the sixth lens G6 and the seventh lens G7 along the optical axis is 0.09mm~0.11mm; the air distance d7 between the seventh lens G7 and the eighth lens G8 along the optical axis is 0.09mm~0.11mm; the air distance d8 between the eighth lens G8 and the ninth lens G9 along the optical axis is 0.09mm~0.11mm; the air distance BFL between the ninth lens G9 and the image plane along the optical axis is 12.1mm~12.4mm.

[0113] The focal length f1 of the first lens G1 is -25.3 mm to -25.0 mm; the focal length f2 of the second lens G2 is 32.4 mm to 32.8 mm; the focal length f3 of the third lens G3 is 27.8 mm to 28.1 mm; the focal length f4 of the fourth lens G4 is -57.2 mm to -56.5 mm; the focal length f5 of the fifth lens G5 is -10.8 mm to -10.6 mm; the focal length f6 of the sixth lens G6 is 28.3 mm to 28.7 mm; the focal length f7 of the seventh lens G7 is 55.4 mm to 56.0 mm; the focal length f8 of the eighth lens G8 is 62.0 mm to 62.7 mm; and the focal length f9 of the ninth lens G9 is 42.3 mm to 42.8 mm.

[0114] The refractive index N1 of the first lens G1 is 1.65-1.7, and the Abbe number V1 is 31.0-31.5; the refractive index N2 of the second lens G2 is 1.75-1.8, and the Abbe number V2 is 49.5-50; the refractive index N3 of the third lens G3 is 1.73-1.78, and the Abbe number V3 is 37.3-37.8; the refractive index N4 of the fourth lens G4 is 1.8-1.85, and the Abbe number V4 is 46.3-46.8; the refractive index N5 of the fifth lens G5 is 1.78-1 .83, and its Abbe number V5 is 25.3-25.8; the refractive index N6 of the sixth lens element G6 is 1.67-1.72, and its Abbe number V6 is 55.3-55.8; the refractive index N7 of the seventh lens element G7 is 1.70-1.75, and its Abbe number V7 is 50-50.5; the refractive index N8 of the eighth lens element G8 is 1.7-1.75, and its Abbe number V8 is 50-50.5; the refractive index N9 of the ninth lens element G9 is 1.8-1.85, and its Abbe number V9 is 46.3-46.8.

[0115] Example 4

[0116] In this example, the working distance of the Sham lens is 339.5mm, the aperture number is F1.8, the diagonal target surface size IMG of the image sensor is 19.5mm, the focal length f is 22mm, and the operating wavelength is 390nm to 480nm. The angle between the target plane and the lens optical axis is 19°, and the system paraxial magnification is -0.061X.

[0117] The focal length f10 of the first lens group 1 is 30.46 mm, the focal length f20 of the second lens group 2 is -28.80 mm, and the focal length f30 of the third lens group 3 is 17.76 mm.

[0118] The curvature radius R11 of the incident surface of the first lens G1 is -36.61mm, and the curvature radius R12 of the exit surface is 37.90mm; the curvature radius R21 of the incident surface of the second lens G2 is 82.21mm, and the curvature radius R22 of the exit surface is -37.60mm; the curvature radius R31 of the incident surface of the third lens G3 is 16.75mm, and the curvature radius R32 of the exit surface is 60.99mm; the curvature radius R41 of the incident surface of the fourth lens G4 is 15.20mm, and the curvature radius R42 of the exit surface is 10.60mm; the curvature radius R51 of the incident surface of the fifth lens G5 is -9.6 The radius of curvature of the incident surface of the sixth lens element G6 is R61, which is 45.45 mm, and the radius of curvature of the exit surface is R62, which is -19.13 mm. The radius of curvature of the incident surface of the seventh lens element G7 is infinite, and the radius of curvature of the exit surface is R72, which is -41.69 mm. The radius of curvature of the incident surface of the eighth lens element G8 is R81, which is -409.97 mm, and the radius of curvature of the exit surface is R82, which is -42.09 mm. The radius of curvature of the incident surface of the ninth lens element G9 is R91, which is 25.41 mm, and the radius of curvature of the exit surface is R92, which is 75.12 mm.

[0119] The center thickness GT1 of the first lens G1 is 2.04 mm; the center thickness GT2 of the second lens G2 is 4.03 mm; the center thickness GT3 of the third lens G3 is 4.21 mm; the center thickness GT4 of the fourth lens G4 is 2.77 mm; the center thickness GT5 of the fifth lens G5 is 2.14 mm; the center thickness GT6 of the sixth lens G6 is 8.29 mm; the center thickness GT7 of the seventh lens G7 is 5.23 mm; the center thickness GT8 of the eighth lens G8 is 5.43 mm; and the center thickness GT9 of the ninth lens G9 is 6.75 mm.

[0120] The air distance d1 between the first lens G1 and the second lens G2 along the optical axis is 5.88 mm; the air distance d2 between the second lens G2 and the third lens G3 along the optical axis is 0.10 mm; the air distance d3 between the third lens G3 and the fourth lens G4 along the optical axis is 0.10 mm; the air distance d4 between the fourth lens G4 and the aperture stop 10 along the optical axis is 1.92 mm; the air distance d5 between the aperture stop 10 and the fifth lens G5 along the optical axis is 9.83 mm; the fifth lens G5 and the sixth lens G6 are a cemented lens; the air distance d6 between the sixth lens G6 and the seventh lens G7 along the optical axis is 0.10 mm; the air distance d7 between the seventh lens G7 and the eighth lens G8 along the optical axis is 0.10 mm; the air distance d8 between the eighth lens G8 and the ninth lens G9 along the optical axis is 0.10 mm; and the air distance BFL between the ninth lens G9 and the image plane along the optical axis is 12.28 mm.

[0121] The focal length f1 of the first lens G1 is -25.24 mm; the focal length f2 of the second lens G2 is 32.78 mm; the focal length f3 of the third lens G3 is 28.08 mm; the focal length f4 of the fourth lens G4 is -57.10 mm; the focal length f5 of the fifth lens G5 is -10.76 mm; the focal length f6 of the sixth lens G6 is 28.65 mm; the focal length f7 of the seventh lens G7 is 55.99 mm; the focal length f8 of the eighth lens G8 is 62.61 mm; and the focal length f9 of the ninth lens G9 is 42.71 mm.

[0122] The refractive index N1 of the first lens element G1 is 1.69, and the Abbe number V1 is 31.2; the refractive index N2 of the second lens element G2 is 1.77, and the Abbe number V2 is 49.6; the refractive index N3 of the third lens element G3 is 1.75, and the Abbe number V3 is 37.5; the refractive index N4 of the fourth lens element G4 is 1.82, and the Abbe number V4 is 46.6; the refractive index N5 of the fifth lens element G5 is 1.81, and the Abbe number V5 is 25.5; the refractive index N6 of the sixth lens element G6 is 1.70, and the Abbe number V6 is 55.5; the refractive index N7 of the seventh lens element G7 is 1.72, and the Abbe number V7 is 50.3; the refractive index N8 of the eighth lens element G8 is 1.72, and the Abbe number V8 is 50.3; and the refractive index N9 of the ninth lens element G9 is 1.82, and the Abbe number V9 is 46.6.

[0123] As shown in Figure 7, the MTF design values ​​for each field of view have a contrast ratio greater than 0.4 at a spatial frequency of 60 lp / mm, which meets the Nyquist frequency requirement of the camera, resulting in higher contrast and clearer imaging.

[0124] An embodiment of the present disclosure further provides an electronic device, which includes an image sensor and the above-mentioned Sham lens, wherein the Sham lens is used to image a target on the image sensor.

[0125] In some embodiments, the electronic device of the present disclosure is a camera, which can be a monocular camera, a binocular camera, or a 3D camera.

[0126] Line laser profilometry technology uses a laser light source to emit a line laser and illuminate the target surface. A 3D camera then uses the reflected laser light to determine the target surface's profile. This technology offers advantages such as high accuracy, speed, and stability. Detection speed, a key performance characteristic of line laser profilometry products, is primarily influenced by the camera chip speed and the lens's ability to receive light.

[0127] When the Sham lens line laser profile measurement technology is used in the present disclosure, the aperture number of the Sham lens is optimized to F1.2~F2.0. The lens has a strong light-receiving ability, and more light energy reaches the chip, and the time required to achieve the same exposure is shorter, which is conducive to improving the detection speed; moreover, the Sham lens of the embodiment of the present disclosure has a large field of view and clear full-frame imaging, and the target surface size of the chip of the adapted camera is large, which is conducive to improving the amount of light entering per unit time, thereby improving the chip's photosensitivity and further improving the detection speed.

[0128] The structure, function and effect of the Sham lens provided in this embodiment are the same as those in the above embodiment. Please refer to the above embodiment for details and will not be described again here.

[0129] In the above description, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" and the like mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present disclosure. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples and features of different embodiments or examples described in this specification without mutual contradiction.

[0130] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present disclosure, rather than to limit them. Although the present disclosure has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present disclosure.

Claims

1. A Sham lens, characterized in that: The Sham lens comprises a plurality of lenses coaxially arranged in sequence from the object side to the image side, wherein the outer diameter of the lens closest to the object side is smaller than the outer diameter of the lens closest to the image side; The incident surface of the lens closest to the object side is concave; the exit surface of the lens closest to the image side is concave.

2. The Sham lens according to claim 1, characterized in that: The outer diameter D1 of the lens closest to the object side and the outer diameter D9 of the lens closest to the image side satisfy 0.3<D1 / D9<0.

8.

3. The Sham lens according to claim 2, characterized in that: The Sham lens includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens and a ninth lens which are coaxially arranged in sequence from the object side to the image side; wherein the first lens is the lens closest to the object side; and the ninth lens is the lens closest to the image side.

4. The Sham lens according to claim 3, characterized in that: The first lens is a biconcave lens, the second lens is a biconvex lens, the third lens is a convex-concave lens, the fourth lens is a convex-concave lens, the fifth lens is a biconcave lens, the sixth lens is a biconvex lens, the seventh lens is a plano-convex lens, the eighth lens is a concave-convex lens, and the ninth lens is a convex-concave lens.

5. The Sham lens according to claim 4, characterized in that: The Sham lens further includes an aperture stop 10 disposed between the fourth lens and the fifth lens, and the fifth lens and the sixth lens are cemented lenses.

6. The Sham lens according to claim 5, characterized in that: The relationship between the outer diameter D4 of the fourth lens and the diameter Dfno of the aperture stop 10 satisfies 1.1<D4 / Dfno<1.7, and the relationship between the diameter Dfno of the aperture stop 10 and the outer diameter D5 of the fifth lens satisfies 0.4<Dfno / D5<0.

7.

7. The Sham lens according to claim 5, characterized in that: The air spacing d1 between the first lens and the second lens along the axial direction is 5mm-7mm; the air spacing d2 between the second lens and the third lens along the axial direction is 0mm-2mm; the air spacing d3 between the third lens and the fourth lens along the axial direction is 0mm-2mm; the spacing d4 between the fourth lens and the aperture stop 10 along the axial direction is 1mm-3mm; the spacing d5 between the aperture stop 10 and the fifth lens along the axial direction is 9mm-11mm; the air spacing d6 between the sixth lens and the seventh lens along the axial direction is 0mm-2mm; the air spacing d7 between the seventh lens and the eighth lens along the axial direction is 0mm-2mm; the air spacing d8 between the eighth lens and the ninth lens along the axial direction is 0mm-2mm.

8. The Sham lens according to any one of claims 3 to 7, characterized in that: The curvature radius R11 of the incident surface of the first lens is -40mm to -30mm, and the curvature radius R12 of the exit surface is 30mm to 40mm; the curvature radius R21 of the incident surface of the second lens is 80mm to 90mm, and the curvature radius R22 of the exit surface is -40mm to -30mm; the curvature radius R31 of the incident surface of the third lens is 10mm to 20mm, and the curvature radius R32 of the exit surface is 55mm to 65mm; the curvature radius R41 of the incident surface of the fourth lens is 10mm to 20mm, and the curvature radius R42 of the exit surface is 5mm to 15mm; the curvature radius R51 of the incident surface of the fifth lens is -15mm to -5 mm, and the radius of curvature R52 of the exit surface is 40mm~50mm; the radius of curvature R61 of the incident surface of the sixth lens is 40mm~50mm, and the radius of curvature R62 of the exit surface is -25mm~-15mm; the radius of curvature R71 of the incident surface of the seventh lens is infinite, and the radius of curvature R72 of the exit surface is -45mm~-35mm; the radius of curvature R81 of the incident surface of the eighth lens is -415mm~-405mm, and the radius of curvature R82 of the exit surface is -50mm~-40mm; the radius of curvature R91 of the incident surface of the ninth lens is 20mm~30mm, and the radius of curvature R92 of the exit surface is 70mm~80mm.

9. The Sham lens according to any one of claims 3 to 7, characterized in that: The center thickness CT1 of the first lens is 1mm to 4mm; the center thickness CT2 of the second lens is 2mm to 5mm; the center thickness CT3 of the third lens is 2mm to 5mm; the center thickness CT4 of the fourth lens is 1mm to 4mm; the center thickness CT5 of the fifth lens is 1mm to 4mm; the center thickness CT6 of the sixth lens is 6mm to 9mm; the center thickness CT7 of the seventh lens is 4mm to 7mm; the center thickness CT8 of the eighth lens is 4mm to 7mm; and the center thickness CT9 of the ninth lens is 4mm to 7mm.

10. The Sham lens according to any one of claims 3 to 7, characterized in that: The focal length f1 of the first lens is -30mm to -20mm; the focal length f2 of the second lens is 30mm to 40mm; the focal length f3 of the third lens is 25mm to 35mm; the focal length f4 of the fourth lens is -60mm to -50mm; the focal length f5 of the fifth lens is -20mm to -10mm; the focal length f6 of the sixth lens is 20mm to 30mm; the focal length f7 of the seventh lens is 50mm to 60mm; the focal length f8 of the eighth lens is 60mm to 70mm; and the focal length f9 of the ninth lens is 40mm to 50mm.

11. The Sham lens according to any one of claims 3 to 7, characterized in that: The refractive index N1 of the first lens is 1.6-1.7, and the Abbe number V1 is 30-35; the refractive index N2 of the second lens is 1.7-1.8, and the Abbe number V2 is 45-50; the refractive index N3 of the third lens is 1.7-1.8, and the Abbe number V3 is 35-40; the refractive index N4 of the fourth lens is 1.8-1.9, and the Abbe number V4 is 45-50; the refractive index N5 of the fifth lens is 1.8 The refractive index N6 of the sixth lens is 1.6-1.7, and the Abbe number V6 is 55-60; the refractive index N7 of the seventh lens is 1.7-1.8, and the Abbe number V7 is 50-55; the refractive index N8 of the eighth lens is 1.7-1.8, and the Abbe number V8 is 50-55; the refractive index N9 of the ninth lens is 1.8-1.9, and the Abbe number V9 is 45-50.

12. The Sham lens according to any one of claims 3 to 7, characterized in that: The outer diameter D1 of the first lens is 20mm-24mm, the outer diameter D2 of the second lens is 20mm-24mm; the outer diameter D3 of the third lens is 18mm-22mm; the outer diameter D4 of the fourth lens is 14mm-18mm; the outer diameter D5 of the fifth lens is 20mm-24mm; the outer diameter D6 of the sixth lens is 23mm-27mm; the outer diameter D7 of the seventh lens is 30mm-34mm; the outer diameter D8 of the eighth lens is 33mm-37mm; and the outer diameter D9 of the ninth lens is 33mm-37mm.

13. The Sham lens according to any one of claims 1 to 7, characterized in that: The focal length f of the Sham lens is 17mm to 50mm; the aperture number of the Sham lens is F1.2 to F2.0; the field of view FOV of the Sham lens is 200mm to 550mm; the working distance WD of the Sham lens is 230mm to 580mm; the working band WL of the Sham lens is 390nm to 480nm; and the MTF@60lp / mm of each field of view of the Sham lens is greater than 0.

48.

14. The Sham lens according to any one of claims 1 to 7, characterized in that: The field of view FOV of the Sham lens and the working distance WD of the Sham lens satisfy 0.3<FOV / WD<2.

5.

15. The Sham lens according to any one of claims 1 to 7, characterized in that: The aperture number of the Sham lens is F1.7 to F1.

9.

16. The Sham lens according to any one of claims 3 to 7, characterized in that: The focal length f10 of the first lens group and the focal length f of the Sham lens satisfy 0.3<f10 / f<2.4; The focal length f20 of the second lens group and the focal length f of the Sham lens satisfy 0.2<|f20 / f|<2.1; The focal length f30 of the third lens group and the focal length f of the Sham lens satisfy 0.1<f30 / f<1.

8.

17. The Sham lens according to any one of claims 3 to 7, characterized in that: The first lens, the second lens, the third lens and the fourth lens form a first lens group, and the focal length f10 of the first lens group is 20 mm to 40 mm; The fifth lens and the sixth lens form a second lens group, and the focal length f20 of the second lens group is -35mm to -15mm; The seventh lens, the eighth lens and the ninth lens form a third lens group, and the focal length f30 of the third lens group is 10 mm to 30 mm; An axial distance d12 between the first lens group and the second lens group is 9 mm to 15 mm; an axial distance d23 between the second lens group and the third lens group is 0 mm to 3 mm.

18. An electronic device, characterized in that: It comprises an image sensor and the Sham lens according to any one of claims 1 to 17, wherein the Sham lens is used to image a target on the image sensor; the target surface diagonal size IMG of the image sensor is 16 mm to 25 mm.

19. The electronic device according to claim 18, characterized in that: The target surface diagonal size IMG of the image sensor is 20 mm to 25 mm.

20. The electronic device according to claim 18, characterized in that The target surface diagonal size IMG of the image sensor and the field of view FOV of the Sham lens satisfy 0.02<IMG / FOV<0.

15.

21. The electronic device according to claim 18, characterized in that: The electronic device is a camera.

Images