LDI optical system
The LDI optical system, designed with a telecentric optical path, solves the problem of limited material selectivity, achieves efficient laser energy utilization and stable direct writing magnification, expands the application range and improves imaging accuracy.
Patent Information
- Application Number
- CN202423279043.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-30
- Publication Date
- 2026-01-13
- Estimated Expiration
- 2034-12-30
AI Technical Summary
Existing LDI technology, due to the use of short-wavelength high-power laser bands, has limited material options when designing optical systems, leading to increased design difficulty.
The LDI optical system, which adopts a telecentric optical path design, includes a first lens group and a second lens group. Both lens groups are positive optical power. The first lens group forms the telecentric optical path, and the second lens group forms the telecentric optical path, supporting a wide spectral band of 365~450nm.
It improves the efficiency of laser energy utilization and the stability of direct writing magnification, expands the application range, and achieves imaging distortion of less than 0.02% and high lens exposure accuracy.
Smart Images
Figure CN223796820U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of laser direct writing imaging technology, specifically to an LDI optical system. Background Technology
[0002] LDI technology uses a laser as the light source, directly exposing patterns onto a photosensitive material using a laser beam. The image is then projected onto a PCB using a digital micromirror device (DMD). The DMD acts as a crucial optical element for imaging, processing the laser light to precisely project the image onto the PCB through an optical system. This results in high image resolution and simpler manufacturing processes. However, LDI technology also has limitations in practical applications: some applications require short-wavelength, high-power lasers, necessitating the use of specific i-line glass materials, limiting material choices and increasing design complexity in the optical system. Summary of the Invention
[0003] The purpose of this invention is to overcome the above-mentioned shortcomings and provide an LDI optical system.
[0004] To achieve the above objectives, the specific solution of this utility model is as follows: An LDI optical system includes a first lens group G1 and a second lens group G2 arranged sequentially from the DMD side to the exposure side; an aperture is provided between the first lens group G1 and the second lens group G2; the optical power of the first lens group G1 and the second lens group G2 are both positive optical powers; the first lens group G1 forms a telecentric optical path; the second lens group G2 forms a telecentric optical path; the focal length of the first lens group G1 is F1; the focal length of the second lens group G2 is F2; wherein, 0.34 <F1 / F2<0.42。
[0005] Further, the first lens group G1 includes a first lens G11, a second lens G12, a third lens G13, a fourth lens G14, a fifth lens G15, and a sixth lens G16 arranged sequentially; the first lens G11 is a plano-convex lens; the second lens G12 is a concave-convex lens; the third lens G13 is a symmetrical biconcave lens; the fourth lens G14 is a symmetrical biconvex lens; the fifth lens G15 is a plano-convex lens; and the sixth lens G16 is a plano-concave lens.
[0006] Further, the object-side radius of curvature of the first lens is R1, and the image-side radius of curvature of the first lens is R2; the object-side radius of curvature of the second lens is R3, and the image-side radius of curvature of the second lens is R4; the object-side radius of curvature of the third lens is R5, and the image-side radius of curvature of the third lens is R6; the object-side radius of curvature of the fourth lens is R7, and the image-side radius of curvature of the fourth lens is R8; the object-side radius of curvature of the fifth lens is R9, and the image-side radius of curvature of the fifth lens is R10; the object-side radius of curvature of the sixth lens is R11, and the image-side radius of curvature of the sixth lens is R12; satisfying the following relationship:
[0007] R1≤-2000mm or R1≥2000mm; -60.45mm≤R2≤-73.90mm;
[0008] 46.53mm≤R3≤56.88mm; 203.04mm≤R4≤248.19mm;
[0009] -38.92mm≤R5≤-47.57m; 38.91mm≤R6≤47.57mm;
[0010] 39.32mm≤R7≤48.07mm; -39.327mm≤R8≤-48.07 mm;
[0011] 18.73mm≤R9≤22.90mm; R10≤-2000mm or R10≥2000mm;
[0012] R11≤-2000mm or R11≥2000mm; 16.82mm≤R12≤20.56mm.
[0013] Further, the distance between the object plane of the DMD and the object-side surface of the first lens ranges from 82.27 mm to 100.57 mm; the distance between the image-side surface of the first lens and the object-side surface of the second lens ranges from 0.62 mm to 0.76 mm; the distance between the image-side surface of the second lens and the object-side surface of the third lens ranges from 28.43 mm to 34.75 mm; the distance between the image-side surface of the third lens and the object-side surface of the fourth lens ranges from 9.92 mm to 12.14 mm; the distance between the image-side surface of the fourth lens and the object-side surface of the fifth lens ranges from 2.35 mm to 2.89 mm; the distance between the image-side surface of the fifth lens and the object-side surface of the sixth lens ranges from 0.36 mm to 0.46 mm; and the distance between the image-side surface of the sixth lens and the aperture ranges from 2.64 mm to 3.24 mm.
[0014] Further, the thickness of the first lens G11 ranges from 5.70mm to 6.98mm; the thickness of the second lens G12 ranges from 7.33mm to 8.97mm; the thickness of the third lens G13 ranges from 1.28mm to 1.58mm; the thickness of the fourth lens G14 ranges from 8.53mm to 10.43mm; the thickness of the fifth lens G15 ranges from 4.56mm to 5.58mm; and the thickness of the sixth lens G16 ranges from 0.9mm to 1.1mm.
[0015] The first lens G11 has a refractive index range of 1.467 to 1.527 and an Abbe number range of 78.345 to 84.875; the second lens G12 has a refractive index range of 1.588 to 1.653 and an Abbe number range of 34.972 to 37.888; the third lens G13 has a refractive index range of 1.549 to 1.613 and an Abbe number range of 39.254 to 42.526. The fourth lens G14 has a refractive index range of 1.467 to 1.527 and an Abbe number range of 78.345 to 84.875; the fifth lens G15 has a refractive index range of 1.467 to 1.527 and an Abbe number range of 78.345 to 84.875; and the sixth lens G16 has a refractive index range of 1.549 to 1.613 and an Abbe number range of 39.254 to 42.526.
[0016] Furthermore, the second lens group G2 includes a seventh lens G21, an eighth lens G22, and a ninth lens G23 arranged sequentially; the seventh lens G21 is a convex-concave lens; the eighth lens G22 is a symmetrical biconvex lens; and the ninth lens G23 is a convex-concave lens.
[0017] Further, the object-side radius of curvature of the seventh lens is R13, and the image-side radius of curvature of the seventh lens is R14; the object-side radius of curvature of the eighth lens is R15, and the image-side radius of curvature of the eighth lens is R16; the object-side radius of curvature of the ninth lens is R17, and the image-side radius of curvature of the ninth lens is R18; satisfying the following relationship:
[0018] -15.18mm≤R13≤-18.57mm, -21.96mm≤R14≤-26.85mm;
[0019] 264.57mm≤R15≤323.37mm, -264.57mm≤R16≤-323.37mm;
[0020] 112.15mm≤R17≤137.09mm, 136.44mm≤R18≤166.76mm.
[0021] Furthermore, the distance between the aperture stop and the object-side surface of the seventh lens is 12.28 mm to 15.02 mm; the distance between the image-side surface of the seventh lens and the object-side surface of the eighth lens is 137.88 mm to 168.54 mm; the distance between the image-side surface of the eighth lens and the object-side surface of the ninth lens is 81.14 mm to 99.18 mm; and the distance between the image-side surface of the ninth lens and the exposure side is 81 mm to 99 mm.
[0022] Furthermore, the thickness of the seventh lens G21 ranges from 10.59mm to 12.95mm; the thickness of the eighth lens G22 ranges from 6.38mm to 7.80mm; and the thickness of the ninth lens G23 ranges from 5.76mm to 7.04mm.
[0023] The refractive index of the seventh lens G21 ranges from 1.587 to 1.653, and its Abbe number ranges from 34.972 to 37.888; the refractive index of the eighth lens G22 ranges from 1.549 to 1.613, and its Abbe number ranges from 39.254 to 42.526; the refractive index of the ninth lens G23 ranges from 1.587 to 1.653, and its Abbe number ranges from 34.972 to 37.888.
[0024] Furthermore, a protective glass is provided between the DMD and the first lens group G1.
[0025] The beneficial effects of this invention are: both the DMD side and the exposure side adopt a telecentric optical path design to ensure the utilization rate of laser energy and the stability of the direct writing magnification. The system supports a wide spectral band of 365~450nm, making it more widely applicable. Attached Figure Description
[0026] The utility model will be further described with reference to the accompanying drawings, but the embodiments in the drawings do not constitute any limitation on the present utility model. For those skilled in the art, other drawings can be obtained based on the following drawings without creative effort.
[0027] Figure 1 This is the optical path diagram for this embodiment;
[0028] Figure 2 This is the optical path diagram of the first lens group G1 in this embodiment;
[0029] Figure 3 This is the optical path diagram of the second lens group G2 in this embodiment;
[0030] Figure 4 This is a diagram of spherical aberration data from the imaging optics simulation of this embodiment;
[0031] Figure 5 This is a diagram of the imaging optical simulation distortion data in this embodiment;
[0032] Figure 6 This is the modulation transfer function (MTF) diagram for the entire field of view in this embodiment.
[0033] Among them: 1. Protective glass; 2. Optical aperture. Detailed Implementation
[0034] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the invention. It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only.
[0035] like Figure 1-6 As shown, an LDI optical system of this embodiment includes a first lens group G1 and a second lens group G2 arranged sequentially from the DMD side to the exposure side; an aperture stop 1 is provided between the first lens group G1 and the second lens group G2; the optical power of the first lens group G1 and the second lens group G2 are both positive optical powers; the first lens group G1 forms a telecentric optical path; the second lens group G2 forms a telecentric optical path; the focal length of the first lens group G1 is F1; the focal length of the second lens group G2 is F2; wherein, 0.34 <F1 / F2<0.42。
[0036] In this embodiment, the first lens group G1 includes a first lens G11, a second lens G12, a third lens G13, a fourth lens G14, a fifth lens G15, and a sixth lens G16 arranged sequentially; the first lens G11 is a plano-convex lens; the second lens G12 is a concave-convex lens; the third lens G13 is a symmetrical biconcave lens; the fourth lens G14 is a symmetrical biconvex lens; the fifth lens G15 is a plano-convex lens; and the sixth lens G16 is a plano-concave lens.
[0037] In this embodiment, the radius of curvature of the object-side surface of the first lens is R1, and the radius of curvature of the image-side surface of the first lens is R2; the radius of curvature of the object-side surface of the second lens is R3, and the radius of curvature of the image-side surface of the second lens is R4; the radius of curvature of the object-side surface of the third lens is R5, and the radius of curvature of the image-side surface of the third lens is R6; the radius of curvature of the object-side surface of the fourth lens is R7, and the radius of curvature of the image-side surface of the fourth lens is R8; the radius of curvature of the object-side surface of the fifth lens is R9, and the radius of curvature of the image-side surface of the fifth lens is R10; the radius of curvature of the object-side surface of the sixth lens is R11, and the radius of curvature of the image-side surface of the sixth lens is R12; satisfying the following relationship:
[0038] R1≤-2000mm or R1≥2000mm; -60.45mm≤R2≤-73.90mm;
[0039] 46.53mm≤R3≤56.88mm; 203.04mm≤R4≤248.19mm;
[0040] -38.92mm≤R5≤-47.57m; 38.91mm≤R6≤47.57mm;
[0041] 39.32mm≤R7≤48.07mm; -39.327mm≤R8≤-48.07 mm;
[0042] 18.73mm≤R9≤22.90mm; R10≤-2000mm or R10≥2000mm;
[0043] R11≤-2000mm or R11≥2000mm; 16.82mm≤R12≤20.56mm.
[0044] Specifically, the object-side surface of the first lens, the image-side surface of the fifth lens, and the object-side surface of the sixth lens can all be set as planes.
[0045] In this embodiment, the distance between the object plane of the DMD and the object-side surface of the first lens ranges from 82.27 mm to 100.57 mm; the distance between the image-side surface of the first lens and the object-side surface of the second lens ranges from 0.62 mm to 0.76 mm; the distance between the image-side surface of the second lens and the object-side surface of the third lens ranges from 28.43 mm to 34.75 mm; the distance between the image-side surface of the third lens and the object-side surface of the fourth lens ranges from 9.92 mm to 12.14 mm; the distance between the image-side surface of the fourth lens and the object-side surface of the fifth lens ranges from 2.35 mm to 2.89 mm; the distance between the image-side surface of the fifth lens and the object-side surface of the sixth lens ranges from 0.36 mm to 0.46 mm; and the distance between the image-side surface of the sixth lens and the aperture stop 2 ranges from 2.64 mm to 3.24 mm.
[0046] In this embodiment, the thickness of the first lens G11 ranges from 5.70mm to 6.98mm; the thickness of the second lens G12 ranges from 7.33mm to 8.97mm; the thickness of the third lens G13 ranges from 1.28mm to 1.58mm; the thickness of the fourth lens G14 ranges from 8.53mm to 10.43mm; the thickness of the fifth lens G15 ranges from 4.56mm to 5.58mm; and the thickness of the sixth lens G16 ranges from 0.9mm to 1.1mm.
[0047] The first lens G11 has a refractive index range of 1.467 to 1.527 and an Abbe number range of 78.345 to 84.875; the second lens G12 has a refractive index range of 1.588 to 1.653 and an Abbe number range of 34.972 to 37.888; the third lens G13 has a refractive index range of 1.549 to 1.613 and an Abbe number range of 39.254 to 42.526. The fourth lens G14 has a refractive index range of 1.467 to 1.527 and an Abbe number range of 78.345 to 84.875; the fifth lens G15 has a refractive index range of 1.467 to 1.527 and an Abbe number range of 78.345 to 84.875; and the sixth lens G16 has a refractive index range of 1.549 to 1.613 and an Abbe number range of 39.254 to 42.526.
[0048] In this embodiment, the second lens group G2 includes a seventh lens G21, an eighth lens G22, and a ninth lens G23 arranged sequentially; the seventh lens G21 is a convex-concave lens; the eighth lens G22 is a symmetrical biconvex lens; and the ninth lens G23 is a convex-concave lens.
[0049] In this embodiment, the radius of curvature of the object-side surface of the seventh lens is R13, and the radius of curvature of the image-side surface of the seventh lens is R14; the radius of curvature of the object-side surface of the eighth lens is R15, and the radius of curvature of the image-side surface of the eighth lens is R16; the radius of curvature of the object-side surface of the ninth lens is R17, and the radius of curvature of the image-side surface of the ninth lens is R18; satisfying the following relationship:
[0050] -15.18mm≤R13≤-18.57mm, -21.96mm≤R14≤-26.85mm;
[0051] 264.57mm≤R15≤323.37mm, -264.57mm≤R16≤-323.37mm;
[0052] 112.15mm≤R17≤137.09mm, 136.44mm≤R18≤166.76mm.
[0053] In this embodiment, the distance between the aperture stop 2 and the object side of the seventh lens is 12.28mm to 15.02mm; the distance between the image side of the seventh lens and the object side of the eighth lens is 137.88mm to 168.54mm; the distance between the image side of the eighth lens and the object side of the ninth lens is 81.14mm to 99.18mm; and the distance between the image side of the ninth lens and the exposure side is 81mm to 99mm.
[0054] In this embodiment, the thickness of the seventh lens G21 ranges from 10.59mm to 12.95mm; the thickness of the eighth lens G22 ranges from 6.38mm to 7.80mm; and the thickness of the ninth lens G23 ranges from 5.76mm to 7.04mm.
[0055] The refractive index of the seventh lens G21 ranges from 1.587 to 1.653, and its Abbe number ranges from 34.972 to 37.888; the refractive index of the eighth lens G22 ranges from 1.549 to 1.613, and its Abbe number ranges from 39.254 to 42.526; the refractive index of the ninth lens G23 ranges from 1.587 to 1.653, and its Abbe number ranges from 34.972 to 37.888.
[0056] In this embodiment, a protective glass 1 is also provided between the DMD and the first lens group G1.
[0057] Specifically, the side of the system closer to the DMD device is the DMD side, and the side closer to the photosensitive material is the exposure side. The laser beam originating from the DMD device passes sequentially through the first lens group G1, the aperture 2, and the second lens group G2 to reach the exposure side. Both the first lens group G1 and the second lens group G2 have positive refractive index optical power. The first lens group G1 forms a telecentric optical path, and the second lens group G2 forms a telecentric optical path, which is a double telecentric optical path. Figure 4-6 The data shows that this invention has a distortion of less than 0.02% in the 365~450nm wide spectral band, which is of excellent quality. In practical applications, the imaging magnification of this invention can be stably maintained at 2.5X, and the lens has high exposure accuracy.
[0058] In addition, the protective glass 1 can be positioned anywhere between the DMD device and the first lens G11.
[0059] The above description is only a preferred embodiment of the present utility model. Therefore, any equivalent changes or modifications made to the structure, features and principles described in the claims of the present utility model patent application are included within the protection scope of the present utility model patent application.
Claims
1. An LDI optical system, characterized in that: It includes a first lens group G1 and a second lens group G2 arranged sequentially from the DMD side to the exposure side; an aperture (2) is provided between the first lens group G1 and the second lens group G2; the optical power of the first lens group G1 and the optical power of the second lens group G2 are both positive optical power. The first lens group G1 forms a telecentric optical path; The second lens group G2 forms a telecentric optical path; The focal length of the first lens group G1 is F1; The focal length of the second lens group G2 is F2; where 0.34 <F1 / F2<0.42。 2. The LDI optical system according to claim 1, characterized in that: The first lens group G1 includes a first lens G11, a second lens G12, a third lens G13, a fourth lens G14, a fifth lens G15, and a sixth lens G16 arranged sequentially. The first lens G11 is a plano-convex lens; the second lens G12 is a concave-convex lens; the third lens G13 is a symmetrical biconcave lens; the fourth lens G14 is a symmetrical biconvex lens; the fifth lens G15 is a plano-convex lens; and the sixth lens G16 is a plano-concave lens.
3. An LDI optical system according to claim 2, characterized in that: The object-side radius of curvature of the first lens is R1, and the image-side radius of curvature of the first lens is R2; the object-side radius of curvature of the second lens is R3, and the image-side radius of curvature of the second lens is R4; the object-side radius of curvature of the third lens is R5, and the image-side radius of curvature of the third lens is R6; the object-side radius of curvature of the fourth lens is R7, and the image-side radius of curvature of the fourth lens is R8; the object-side radius of curvature of the fifth lens is R9, and the image-side radius of curvature of the fifth lens is R10; the object-side radius of curvature of the sixth lens is R11, and the image-side radius of curvature of the sixth lens is R12; satisfying the following relationship: R1≤-2000mm or R1≥2000mm; -60.45mm≤R2≤-73.90mm; 46.53mm≤R3≤56.88mm; 203.04mm≤R4≤248.19mm; -38.92mm≤R5≤-47.57m; 38.91mm≤R6≤47.57mm; 39.32mm≤R7≤48.07mm; -39.327mm≤R8≤-48.07 mm; 18.73mm≤R9≤22.90mm; R10≤-2000mm or R10≥2000mm; R11≤-2000mm or R11≥2000mm; 16.82mm≤R12≤20.56mm.
4. An LDI optical system according to claim 2, characterized in that: The distance between the object plane of the DMD and the object side surface of the first lens ranges from 82.27 mm to 100.57 mm. The distance between the image-side surface of the first lens and the object-side surface of the second lens ranges from 0.62mm to 0.76mm. The distance between the image-side surface of the second lens and the object-side surface of the third lens ranges from 28.43 mm to 34.75 mm. The distance between the image side of the third lens and the object side of the fourth lens is 9.92mm to 12.14mm. The distance between the image side of the fourth lens and the object side of the fifth lens is 2.35mm to 2.89mm. The distance between the image side of the fifth lens and the object side of the sixth lens is 0.36mm to 0.46mm. The distance between the image side of the sixth lens and the aperture stop (2) is 2.64mm to 3.24mm.
5. An LDI optical system according to claim 2, characterized in that: The thickness of the first lens G11 ranges from 5.70 mm to 6.98 mm; The thickness of the second lens G12 ranges from 7.33 mm to 8.97 mm; The thickness of the third lens G13 ranges from 1.28 mm to 1.58 mm; The thickness of the fourth lens G14 ranges from 8.53 mm to 10.43 mm; The thickness of the fifth lens G15 ranges from 4.56 mm to 5.58 mm; The thickness of the sixth lens G16 ranges from 0.9 mm to 1.1 mm; The refractive index of the first lens G11 ranges from 1.467 to 1.527, and its Abbe number ranges from 78.345 to 84.
875. The refractive index of the second lens G12 ranges from 1.588 to 1.653, and its Abbe number ranges from 34.972 to 37.
888. The refractive index of the third lens G13 ranges from 1.549 to 1.613, and its Abbe number ranges from 39.254 to 42.
526. The refractive index of the fourth lens G14 ranges from 1.467 to 1.527, and its Abbe number ranges from 78.345 to 84.
875. The refractive index of the fifth lens G15 ranges from 1.467 to 1.527, and its Abbe number ranges from 78.345 to 84.
875. The refractive index of the sixth lens G16 ranges from 1.549 to 1.613, and its Abbe number ranges from 39.254 to 42.
526.
6. An LDI optical system according to claim 1, characterized in that: The second lens group G2 includes a seventh lens G21, an eighth lens G22, and a ninth lens G23 arranged sequentially; The seventh lens G21 is a convex-concave lens; the eighth lens G22 is a symmetrical biconvex lens; and the ninth lens G23 is a convex-concave lens.
7. An LDI optical system according to claim 6, characterized in that: The object-side radius of curvature of the seventh lens is R13, and the image-side radius of curvature of the seventh lens is R14; the object-side radius of curvature of the eighth lens is R15, and the image-side radius of curvature of the eighth lens is R16; the object-side radius of curvature of the ninth lens is R17, and the image-side radius of curvature of the ninth lens is R18; satisfying the following relationship: -15.18mm≤R13≤-18.57mm, -21.96mm≤R14≤-26.85mm; 264.57mm≤R15≤323.37mm, -264.57mm≤R16≤-323.37mm; 112.15mm≤R17≤137.09mm, 136.44mm≤R18≤166.76mm.
8. An LDI optical system according to claim 6, characterized in that: The distance between the aperture stop (2) and the object side of the seventh lens is 12.28 mm to 15.02 mm. The distance between the image side of the seventh lens and the object side of the eighth lens is 137.88mm to 168.54mm. The distance between the image side of the eighth lens and the object side of the ninth lens is 81.14mm to 99.18mm. The distance between the image side and the exposure side of the ninth lens is 81mm to 99mm.
9. An LDI optical system according to claim 6, characterized in that: The thickness of the seventh lens G21 ranges from 10.59 mm to 12.95 mm; The thickness of the eighth lens G22 ranges from 6.38 mm to 7.80 mm; The thickness of the ninth lens G23 ranges from 5.76 mm to 7.04 mm. The refractive index of the seventh lens G21 ranges from 1.587 to 1.653, and its Abbe number ranges from 34.972 to 37.
888. The refractive index of the eighth lens G22 ranges from 1.549 to 1.613, and its Abbe number ranges from 39.254 to 42.
526. The refractive index of the ninth lens G23 ranges from 1.587 to 1.653, and its Abbe number ranges from 34.972 to 37.
888.
10. An LDI optical system according to claim 1, characterized in that: A protective glass (1) is also provided between the DMD and the first lens group G1.