35mm line scanning lens and optical system
The 35mm line scan lens with eleven spherical lenses and cemented groups addresses the limitations of conventional lenses by ensuring high resolution and consistent imaging quality across large surfaces and temperature variations.
Patent Information
- Application Number
- CN202323663055.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2023-12-29
- Publication Date
- 2024-12-31
- Estimated Expiration
- 2033-12-29
AI Technical Summary
Conventional line scan lenses are expensive, have limited imaging field of view, poor edge resolution, and suffer from thermal defocus in varying temperatures, leading to image blurring.
A 35mm line scan lens design comprising eleven spherical lenses with specific refractive indices and configurations, including cemented lens groups, to correct aberrations and maintain image quality across large target surfaces and varying temperatures.
The lens design achieves high resolution and consistent imaging quality across the entire target surface, with reduced manufacturing costs and clear imaging in extreme temperatures (-40℃ to 80℃).
Smart Images
Figure CN222280935U_ABST
Abstract
Description
Technical Field
[0001] The present disclosure relates to the technical field of optical lenses, and in particular to a 35mm line scan lens and an optical system. Background Art
[0002] 1. Conventional line scanning lenses, when imaging on a large target surface, mostly use aspherical glass lenses to correct the off-axis aberration of the system, and the overall price is relatively expensive.
[0003] 2. For line scan lenses with similar focal lengths, the closest object distance for imaging is mostly around 200mm due to the limited imaging field of view.
[0004] 3. For line scan lenses with similar focal lengths, when the target surface becomes larger, the resolution between the center and the edge is usually quite different, and the image quality at the edge is poor.
[0005] 4. Conventional lenses will produce thermal defocus in high and low temperature environments, causing the image to become blurred. Utility Model Content
[0006] The purpose of the utility model is to solve the above-mentioned problem and provide a 35mm line scanning lens and an optical system.
[0007] The technical solution of the present disclosure is achieved as follows:
[0008] In a first aspect, the present disclosure provides a 35 mm line scan lens, comprising: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, an aperture, a sixth lens, a seventh lens, an eighth lens, a ninth lens, a tenth lens and an eleventh lens arranged in sequence from an object side to an image side along an optical axis,
[0009] The object side is convex, the image side is concave, and the refractive index is: 1.8;
[0010] The second lens has a negative refractive power, a flat object side surface, a concave image side surface, and a refractive index of 1.5;
[0011] The third lens has positive refractive power, the object side surface is convex, the image side surface is convex, and the refractive index is: 2;
[0012] The fourth lens has positive refractive power, the object side surface is convex, the image side surface is concave, and the refractive index is 1.6;
[0013] The fifth lens has positive refractive power, the object side surface is concave, the image side surface is convex, and the refractive index is 1.9;
[0014] The sixth lens has a negative refractive power, a concave object side surface, a concave image side surface, and a refractive index of 1.6;
[0015] The seventh lens has positive refractive power, the object side surface is convex, the image side surface is convex, and the refractive index is 1.6;
[0016] The eighth lens has positive refractive power, the object side surface is concave, the image side surface is convex, and the refractive index is 1.6;
[0017] The ninth lens has a negative refractive power, a concave object side surface, a convex image side surface, and a refractive index of 2;
[0018] The tenth lens has positive refractive power, the object side surface is convex, the image side surface is convex, and the refractive index is: 2;
[0019] The eleventh lens has negative refractive power, the object side surface is concave, the image side surface is concave, and the refractive index is 1.5.
[0020] The advantages or beneficial effects of the above technical solution include at least:
[0021] 1. While taking into account the large target surface, a reasonable lens combination is adopted to meet the imaging quality requirements and reduce manufacturing costs.
[0022] 2. Meet the needs of wide working distance imaging, the minimum working distance that can take into account imaging is 130mm.
[0023] 3. Achieve high resolution across the entire target surface, and the imaging quality is relatively consistent from the center to the edge.
[0024] 4. The optical athermal design is adopted to output high-definition images in high and low temperature environments (-40℃ to 80℃).
[0025] In a second aspect, the present disclosure further provides an optical system, comprising the 35mm line scan lens described in any one of the above items.
[0026] The advantages or beneficial effects of the above technical solution include at least:
[0027] Including any of the 35mm line scan lenses described above; the beneficial effects of this optical system have been clearly explained in the above-mentioned 35mm line scan lenses and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS
[0028] The accompanying drawings illustrate exemplary embodiments of the present disclosure of embodiments of the utility model and, together with the description, are used to explain the principles of the present disclosure. These drawings are included to provide a further understanding of the present disclosure, and the accompanying drawings are included in and constitute a part of this specification.
[0029] Figure 1 The MTF diagram of the first embodiment of the utility model is shown;
[0030] Figure 2The distortion curve of the first embodiment of the utility model is shown;
[0031] Figure 3 The relative illumination of the first embodiment of the utility model is shown;
[0032] Figure 4 The lens arrangement diagram of the first embodiment of the utility model is shown (from left to right, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the aperture, the sixth lens, the seventh lens, the eighth lens, the ninth lens, the tenth lens, the eleventh lens, the protective sheet and the image plane);
[0033] Figure 5 The MTF diagram of the second embodiment of the utility model is shown;
[0034] Figure 6 The distortion curve of the second embodiment of the utility model is shown;
[0035] Figure 7 The relative illumination of the second embodiment of the utility model is shown;
[0036] Figure 8 The lens arrangement diagram of the second embodiment of the present utility model is shown (from left to right, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the aperture, the sixth lens, the seventh lens, the eighth lens, the ninth lens, the tenth lens, the eleventh lens, the protective sheet and the image plane) DETAILED DESCRIPTION
[0037] Embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although certain embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be construed as being limited to the embodiments set forth herein, which are instead provided for a more thorough and complete understanding of the present disclosure. It should be understood that the drawings and embodiments of the present disclosure are only for exemplary purposes and are not intended to limit the scope of protection of the present disclosure.
[0038] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in the present disclosure may be combined with each other. The present disclosure will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.
[0039] It should be understood that the term "including" and its variations used in this document are open inclusions, that is, "including but not limited to". The term "based on" means "based at least in part on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one other embodiment"; the term "some embodiments" means "at least some embodiments". Relevant definitions of other terms will be given in the description below. It should be noted that the concepts of "first", "second", etc. mentioned in this disclosure are only used to distinguish different devices, modules or units, and are not used to limit the order or interdependence of the functions performed by these devices, modules or units.
[0040] It should be noted that the modifications of "one" and "plurality" mentioned in the present disclosure are illustrative rather than restrictive, and those skilled in the art should understand that unless otherwise clearly indicated in the context, it should be understood as "one or more".
[0041] The names of the messages or information exchanged between multiple devices in the embodiments of the present disclosure are only used for illustrative purposes and are not used to limit the scope of these messages or information.
[0042] A 35mm line scan lens, specifically, the lens adopts a line scan lens with a focal length of 35mm, and the lens includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, an aperture, a sixth lens, a seventh lens, an eighth lens, a ninth lens, a tenth lens and an eleventh lens arranged in sequence from the object side to the image side along the optical axis.
[0043] The first lens has a negative refractive power, a convex object side surface, a concave image side surface, and a refractive index of 1.8;
[0044] The second lens has a negative refractive power, a flat object side surface, a concave image side surface, and a refractive index of 1.5;
[0045] The third lens has positive refractive power, the object side surface is convex, the image side surface is convex, and the refractive index is: 2;
[0046] The fourth lens has positive refractive power, the object side surface is convex, the image side surface is concave, and the refractive index is 1.6;
[0047] The fifth lens has positive refractive power, the object side surface is concave, the image side surface is convex, and the refractive index is 1.9;
[0048] The sixth lens has a negative refractive power, a concave object side surface, a concave image side surface, and a refractive index of 1.6;
[0049] The seventh lens has positive refractive power, the object side surface is convex, the image side surface is convex, and the refractive index is 1.6;
[0050] The eighth lens has positive refractive power, the object side surface is concave, the image side surface is convex, and the refractive index is 1.6;
[0051] The ninth lens has a negative refractive power, a concave object side surface, a convex image side surface, and a refractive index of 2;
[0052] The tenth lens has positive refractive power, the object side surface is convex, the image side surface is convex, and the refractive index is: 2;
[0053] The eleventh lens has a negative refractive power, a concave object side surface, a concave image side surface, and a refractive index of 1.5; the focal length f11 of the eleventh lens satisfies the following relationship: f11<0;
[0054] This patented lens uses a total of eleven spherical lenses. By reasonably allocating the optical focal length of each lens, a linear scanning lens with a focal length of 35mm is realized. The maximum target surface size can reach 45mm, which is larger than similar products. The lens has an overall size of φ65*74mm, and the maximum lens outer diameter is less than 44mm. Furthermore, an adjustable aperture can be placed inside the structure, and the achievable aperture range is F2.8-F22.
[0055] Further, the seventh lens and the eighth lens are combined into a cemented lens; the ninth lens and the tenth lens are combined into a cemented lens, and both groups of the cemented lenses satisfy the relationship: |Vd 正 -Vd 负 |>35; where Vd 正 is the Abbe number of the positive lens, Vd 负 is the Abbe number of the negative lens. This lens combination can effectively correct chromatic aberration, especially it is very helpful to optimize the position chromatic aberration under different working distances.
[0056] Furthermore, the tenth lens and the eleventh lens are combined into an achromatic cemented lens, the refractive index of the tenth lens is defined as n10, the Abbe number is defined as Vd10, the refractive index of the eleventh lens is defined as n11, the Abbe number is defined as Vd11, and the following relationship is satisfied: 0.4<|n10-n11|<0.6, 20<|Vd10-Vd11|<25. This group of cemented lenses is placed in front of the image plane, mainly used to correct off-axis aberrations, thereby improving image quality.
[0057] Furthermore, the optical system of the lens satisfies the following relationship: 1<|y / f|<1.3; wherein y is the image height of the optical system, and f is the focal length of the optical system
[0058] Furthermore, the optical system of the lens satisfies the following relationship: dn7 / Dt<0, dn8 / Dt<0; dn7 / Dt is the refractive index temperature coefficient of the seventh lens, and dn8 / Dt is the refractive index temperature coefficient of the eighth lens; this is conducive to the optical athermal design of the system, ensuring clear imaging in an environment of high temperature of 80 degrees Celsius and low temperature of minus 40 degrees Celsius.
[0059] In the first embodiment, the parameters of the first to eleventh lenses are shown in Table 1:
[0060] Table 1:
[0061]
[0062] Among them, the focal length parameters of the first to eleventh lenses are shown in Table 2:
[0063] Table 2:
[0064] LENS focal length (1-2)P1 -52 (3-4)P2 -55.3 (5-6)P3 54.53 (7-8)P4 93.9 (9-10)P5 64.4 (12-13)P6 -32.5 (13-14)P7 29.2 (15-16)P8 35.4 (16-17)P9 -41.1 (18-19)P10 53.2 (19-20)P11 -52.3 (21-22)P12 Infinity
[0065] In the second embodiment, the parameters of the first to eleventh lenses are shown in Table 3:
[0066] Table 3:
[0067]
[0068] Among them, the focal length parameters of the first to eleventh lenses are shown in Table 4:
[0069] Table 4:
[0070] LENS focal length (1-2)P1 -55.9 (3-4)P2 -55.6 (5-6)P3 54.7 (7-8)P4 105.9 (9-10)P5 66.8 (12-13)P6 -32.5 (13-14)P7 28.9 (15-16)P8 37.1 (16-17)P9 -45.3 (18-19)P10 53.6 (19-20)P11 -52.2 (21-22)P12 Infinity
[0071] The comparison of optical system parameters of the first embodiment and the second embodiment is shown in Table 5:
[0072] Table 5:
[0073] Example 1 Example 2 f 35 35 WD 330 250 BFL 29.6 30 BFL / f 0.8457143 0.85714 y 45 45 y / f 1.2857143 1.28571 TTL 121.6 124 BFL / TTL 0.2434211 0.24194
[0074] Among them, f is the focal length of the optical system; WD is the object distance; BFL is the optical back focus of the optical system; y is the image height (the total image height of the image on the sensor); TTL optical total length (the distance from the first surface of the first lens to the image plane) is in mm. The difference between WD and WD is that the optimal working distance is different.
[0075] The present application also provides an optical system, comprising the 35mm line scan lens described in any one of the above items; the beneficial effects of this optical system have been clearly explained in the above-mentioned 35mm line scan lens and will not be repeated here.
[0076] In the description of the present disclosure, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present disclosure.
[0077] Those skilled in the art should understand that the above embodiments are only for the purpose of clearly illustrating the present disclosure, and are not intended to limit the scope of the present disclosure. For those skilled in the art, other changes or modifications may be made based on the above disclosure, and these changes or modifications are still within the scope of the present disclosure.
Claims
1. A 35mm line scan lens, characterized in that: include: A first lens, a second lens, a third lens, a fourth lens, a fifth lens, an aperture stop, a sixth lens, a seventh lens, an eighth lens, a ninth lens, a tenth lens and an eleventh lens arranged in order from the object side to the image side along the optical axis; The first lens has a negative refractive power, a convex object side surface, a concave image side surface, and a refractive index of 1.8; The second lens has a negative refractive power, a flat object side surface, a concave image side surface, and a refractive index of 1.5; The third lens has positive refractive power, the object side surface is convex, the image side surface is convex, and the refractive index is: 2; The fourth lens has positive refractive power, the object side surface is convex, the image side surface is concave, and the refractive index is 1.6; The fifth lens has positive refractive power, the object side surface is concave, the image side surface is convex, and the refractive index is 1.9; The sixth lens has a negative refractive power, a concave object side surface, a concave image side surface, and a refractive index of 1.6; The seventh lens has positive refractive power, the object side surface is convex, the image side surface is convex, and the refractive index is 1.6; The eighth lens has positive refractive power, the object side surface is concave, the image side surface is convex, and the refractive index is 1.6; The ninth lens has a negative refractive power, a concave object side surface, a convex image side surface, and a refractive index of 2; The tenth lens has positive refractive power, the object side surface is convex, the image side surface is convex, and the refractive index is: 2; The eleventh lens has negative refractive power, the object side surface is concave, the image side surface is concave, and the refractive index is 1.
5.
2. The 35 mm line scan lens according to claim 1, characterized in that: The seventh lens and the eighth lens are combined into a cemented lens; the ninth lens and the tenth lens are combined into a cemented lens; And the two groups of glued lenses both satisfy the relationship: |Vd 正 -Vd 负 |>35; Among them, Vd 正 is the Abbe number of the positive lens, Vd 负 is the Abbe number of the negative lens.
3. The 35 mm line scan lens according to claim 2, characterized in that: The tenth lens and the eleventh lens are combined to form an achromatic cemented lens. And the optical system satisfies the following relationship: 0.4<|n10-n11|<0.6, 20<|Vd10-Vd11|<25; n10 is the refractive index of the tenth lens, Vd10 is the Abbe number, n11 is the refractive index of the eleventh lens, and Vd11 is the Abbe number.
4. The 35 mm line scan lens according to claim 3, characterized in that: The optical system of the lens satisfies the following relationship: f11<0; wherein f11 is the focal length of the eleventh lens.
5. The 35 mm line scan lens according to claim 1, characterized in that: The optical system of the lens satisfies the following relationship: 1<|y / f|<1.3; wherein y is the image height of the optical system, and f is the focal length of the optical system.
6. The 35 mm line scan lens according to claim 1, characterized in that: The optical system of the lens satisfies the following relationship: dn7 / Dt<0, dn8 / Dt<0; dn7 / Dt is the refractive index temperature coefficient of the seventh lens, and dn8 / Dt is the refractive index temperature coefficient of the eighth lens.
7. The 35 mm line scan lens according to claim 1, characterized in that: The outer dimensions of the lens are φ65*74mm, and the maximum outer diameter of the lens is less than 44mm.
8. An optical system, characterized in that: Comprising the 35mm line scan lens as described in any one of claims 1-7.