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CN-122018111-A - Focusing ultraviolet micro-lens

CN122018111ACN 122018111 ACN122018111 ACN 122018111ACN-122018111-A

Abstract

The application discloses a focusing ultraviolet micro-lens which comprises a lens base, a focusing ring, a fixed lens group, a movable lens group and an imaging sensor, wherein the fixed lens group and the movable lens group are sequentially arranged in the lens base from an object side to an image side along an optical axis, the focusing ring is connected with the movable lens group and used for adjusting the movable lens group to move along the optical axis so as to realize focal length adjustment, the fixed lens group comprises a first lens and a second lens which are sequentially arranged from the object side to the image side, the movable lens group comprises a third lens, a fourth lens and a fifth lens which are sequentially arranged from the object side to the image side, and ultraviolet antireflection films are plated on the surfaces of the first lens to the fifth lens. According to the application, through a five-piece lens structure combining a fixed lens group and a movable lens group, the focal length is continuously adjustable, and the fused quartz and calcium fluoride materials are matched with the ultraviolet antireflection film, so that the ultraviolet band imaging quality and focusing stability are improved, and the lens is suitable for scenes such as semiconductor defect detection, micro part imaging and biological microstructure observation.

Inventors

  • LI BINGXUAN
  • ZHANG GE

Assignees

  • 闽都创新实验室

Dates

Publication Date
20260512
Application Date
20260325

Claims (10)

  1. 1. The focusing ultraviolet micro-lens is characterized by comprising a lens seat (11), a focusing ring (12), a fixed lens group (13), a movable lens group (14) and an imaging sensor (15), wherein the fixed lens group (13) and the movable lens group (14) are sequentially arranged in the lens seat (11) from an object side to an image side along an optical axis, and the focusing ring (12) is connected with the movable lens group (14) and is used for adjusting the movable lens group (14) to move along the optical axis so as to realize focal length adjustment; The fixed lens group (13) comprises a first lens (131) and a second lens (132) which are arranged from the object side to the image side in sequence; The movable lens group (14) comprises a third lens (141), a fourth lens (142) and a fifth lens (143) which are arranged from the object side to the image side in sequence; the surfaces of the first lens (131) to the fifth lens (143) are plated with ultraviolet antireflection films.
  2. 2. The adjustable-focus ultraviolet macro lens according to claim 1, wherein the first lens (131) is a biconcave spherical lens with negative optical power, and is made of fused quartz material; The second lens (132) is a biconvex spherical lens with positive focal power and is made of calcium fluoride material.
  3. 3. The adjustable-focus ultraviolet macro lens according to claim 1, wherein the third lens (141) is a meniscus lens of positive power, and is made of fused quartz material; The fourth lens (142) is a biconcave spherical lens with negative focal power and is made of calcium fluoride material; the fifth lens (143) is a biconvex spherical lens with positive focal power and adopts fused quartz material.
  4. 4. The adjustable-focus ultraviolet macro lens according to claim 1, wherein the wavelength range of the ultraviolet antireflection film is 300nm-400nm, and the transmittance in the wavelength range is not less than 85%.
  5. 5. The adjustable-focus ultraviolet micro-lens according to claim 1, wherein the focusing ring (12) and the lens seat (11) are connected by screw threads, the focusing precision is 0.01mm, the moving range of the moving lens group (14) is 5-10mm, and the focal length is adjustable between 20-35 mm; preferably, the focusing ring (12) and the lens seat (11) are connected by adopting fine threads, and the moving range of the moving lens group (14) is 8mm.
  6. 6. The adjustable-focus ultraviolet macro lens according to claim 1, wherein the numerical aperture of the adjustable-focus ultraviolet macro lens (10) is 0.4-0.5, distortion is less than or equal to 0.1%, and resolution is more than or equal to 100 line pairs/mm.
  7. 7. The adjustable-focus ultraviolet macro lens according to claim 1, further comprising an aperture stop (16), the aperture stop (16) being disposed between the fixed lens group (13) and the moving lens group (14); Preferably, the aperture of the aperture stop (16) is 3mm for adjusting the amount of light entering.
  8. 8. The adjustable focus ultraviolet macro lens according to any of claims 1 to 7, wherein the adjustable focus ultraviolet macro lens (10) is suitable for semiconductor micro defect detection, micro-part ultraviolet imaging or biological microstructure observation scenes.
  9. 9. A tunable ultraviolet macro lens according to claim 2 or 3, characterised in that the refractive index nd=1.46 of the first lens (131) and the dispersion coefficient vd=67.8; The refractive index nd=1.43 of the second lens (132), and the dispersion coefficient vd=95.
  10. 10. A focusing ultraviolet macro lens according to claim 3, characterized in that the third lens (141) has a focal length of 35mm and a central thickness of 3.2mm; The focal length of the fourth lens (142) is-42 mm, and the center thickness is 2.5mm; the focal length of the fifth lens (143) is 30mm, and the center thickness is 3.0mm.

Description

Focusing ultraviolet micro-lens Technical Field The application relates to a focusing ultraviolet micro-lens, and belongs to the technical field of optical lenses. Background In the field of microscopic detection, an ultraviolet micro-lens is a key optical component in application scenes such as semiconductor defect detection, micro part imaging, biological microstructure observation and the like. At present, the technical scheme adopted in the field is that an ultraviolet band optical lens mainly concentrates the working wavelength in the range of 300nm-400nm, and light ray convergence and imaging are realized through a plurality of lens combinations. The existing ultraviolet micro-lens generally adopts optical materials with higher ultraviolet transmittance such as fused quartz, calcium fluoride and the like to manufacture a lens, and an antireflection film is plated on the surface of the lens so as to improve the transmittance of ultraviolet bands. In terms of structural design, the existing lens is in a form of a fixed lens group, a lens is fixedly mounted in a lens seat along the optical axis direction, part of products are provided with a focusing mechanism to realize a focal length adjusting function, the focusing mode comprises a threaded connection mode, a gear transmission mode or an electric driving mode and the like, and an imaging sensor is arranged on the image side of the lens and used for receiving optical signals. However, the existing ultraviolet micro-lens is mainly designed in fixed focus, the focal length cannot be flexibly adjusted to meet the detection requirements of microscopic targets with different distances and sizes, the ultraviolet lens with a focusing function adopts a complex focusing mechanism, so that the whole size is huge, the focusing precision is insufficient, the use requirements of high-precision microscopic detection are difficult to meet, meanwhile, the existing adjustable focusing lens is poor in imaging quality in an ultraviolet band, large in distortion, poor in stability of a lens group in a focusing process, and easy to cause an image shift phenomenon, and detection precision and imaging consistency are influenced. Disclosure of Invention The invention relates to a focusing ultraviolet micro-lens, which aims to solve the technical problems that the existing ultraviolet micro-lens is mostly of fixed focus design, the focus cannot be flexibly adjusted to meet the detection requirements of microscopic targets with different distances and sizes, the focusing precision of the ultraviolet lens with a focusing function is insufficient, the use requirement of high-precision microscopic detection is difficult to meet, meanwhile, the existing focusing lens is poor in imaging quality in an ultraviolet band, large in distortion, and poor in stability of a lens group in the focusing process, an image shift phenomenon is easy to occur, and the detection precision and the imaging consistency are influenced. In order to achieve the above object, the present application provides the following technical solutions: The application provides a focusing ultraviolet micro-lens, which comprises a lens base, a focusing ring, a fixed lens group, a movable lens group and an imaging sensor, wherein the fixed lens group and the movable lens group are sequentially arranged in the lens base from an object side to an image side along an optical axis, and the focusing ring is connected with the movable lens group and is used for adjusting the movable lens group to move along the optical axis so as to realize focal length adjustment; The fixed lens group comprises a first lens and a second lens which are sequentially arranged from an object side to an image side; the movable lens group comprises a third lens, a fourth lens and a fifth lens which are sequentially arranged from an object side to an image side; the surfaces of the first lens and the fifth lens are plated with ultraviolet antireflection films. Optionally, the first lens is a biconcave spherical lens with negative focal power, and adopts fused quartz material; the second lens is a biconvex spherical lens with positive focal power and is made of calcium fluoride material. Optionally, the third lens is a meniscus lens with positive focal power, and adopts fused quartz material; the fourth lens is a biconcave spherical lens with negative focal power and is made of calcium fluoride material; The fifth lens is a biconvex spherical lens with positive focal power and adopts fused quartz materials. Optionally, the wavelength range of the ultraviolet antireflection film is 300nm-400nm, and the transmittance in the wavelength range is more than or equal to 85%. Optionally, the focusing ring is in threaded connection with the lens seat, the focusing precision is 0.01mm, the moving range of the movable lens group is 5-10mm, and the focal length is adjustable between 20-35 mm; preferably, the focusing ring is connected with the lens seat by adop