CN212515191U - Short-distance identification lens - Google Patents
Short-distance identification lens Download PDFInfo
- Publication number
- CN212515191U CN212515191U CN202022293637.8U CN202022293637U CN212515191U CN 212515191 U CN212515191 U CN 212515191U CN 202022293637 U CN202022293637 U CN 202022293637U CN 212515191 U CN212515191 U CN 212515191U
- Authority
- CN
- China
- Prior art keywords
- lens
- optical axis
- image
- focal length
- distance
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Lenses (AREA)
Abstract
The invention discloses a short-distance identification lens, which is sequentially provided with a diaphragm (STO), a first lens (E1), a second lens (E2), a third lens (E3), a fourth lens (E4) and chip protective glass (E5) from an object plane to an image plane; the first lens element (E1) is a positive lens element, has a convex object-side surface and a convex image-side surface, and is aspheric; the second lens (E2) is a negative lens, the object side surface is a convex surface, the image side surface is a concave surface, and the second lens is an aspheric surface; the third lens (E3) is a positive lens, the object side surface is a concave surface, the image side surface is a convex surface, and the third lens is an aspheric surface; the fourth lens (E4) is a negative lens, the object side surface is a convex surface, the image side surface is a convex surface, and the fourth lens is an aspheric surface; the four lenses are made of plastic materials, so that the structure is simple, the tolerance sensitivity is low, and mass production is facilitated; the positive lens and the negative lens are combined with each other to facilitate correction of astigmatism and distortion, and at the same time, to facilitate reduction of the total length of the optical system.
Description
[ technical field ] A method for producing a semiconductor device
The invention relates to a short-distance identification lens.
[ background of the invention ]
With social development and technological progress, more and more high-end technological products are in the middle of life of people. The invention relates to an identification lens which has low tolerance sensitivity and is suitable for mass production, can meet the use requirement of short-distance identification, and has optical lenses made of plastic materials, thereby saving the cost and being suitable for efficient mass production.
[ summary of the invention ]
The invention provides a short-distance identification lens aiming at the requirements of the existing market and the space for improving the investigation, and aims to solve the technical problem that the optical caliber of the existing identification lens is not small enough, the imaging quality cannot be guaranteed, and the existing identification lens has small distortion.
In order to achieve the above object, the present invention provides a short-distance recognition lens, comprising a Stop (STO), a first lens (E1), a second lens (E2), a third lens (E3), a fourth lens (E4), and a chip protection glass (E5) arranged in this order from an object plane to an image plane;
the first lens (E1) is a positive lens made of plastic, and the focal length of the first lens (E1) is 0.5< f1/f < 1.1; the object side surface is a convex surface and is an aspheric surface, and the image side surface is a convex surface and is an aspheric surface;
the second lens (E2) is a negative lens and is made of plastic, and the focal length meets the requirement that the focal length is-1.85 < f2/f < -1.52; the object side surface is a convex surface and is an aspheric surface, and the image side surface is a concave surface and is an aspheric surface;
the third lens (E3) is a positive lens made of plastic, and the focal length of the third lens (E3) is 0.52< f3/f < 1.2; the object side surface is a concave surface and is an aspheric surface, and the image side surface is a convex surface and is an aspheric surface;
the fourth lens (E4) is a negative lens made of plastic, and the focal length meets the requirement that the focal length is-0.8 < f4/f < 0; the object side surface is a convex surface and is an aspheric surface, and the image side surface is a convex surface and is an aspheric surface;
the close-range identification lens satisfies the following relational expression: 1.28< TTL/f < 1.5;
wherein f1 is the effective focal length of the first lens element, f2 is the effective focal length of the second lens element, f3 is the effective focal length of the third lens element, f4 is the effective focal length of the fourth lens element, and TTL is the on-axis distance from the object-side surface of the first lens element to the image plane; f is the effective focal length of the close-range identification lens.
Preferably, the short-distance identification lens satisfies the following relation: 0.02< T12/f < 0.03; 0.03< T34/f < 0.04;
where T12 is an air space on the optical axis of the first lens and the second lens, and T34 is an air space on the optical axis of the third lens and the fourth lens.
Preferably, the short-distance identification lens is provided with a diaphragm positioned between the object side surface of the first lens and the object and satisfying the following conditions
The following relations:
0<TDS/f1<0.4；
wherein TDS is aperture diaphragm aperture, and f1 is first lens focal length.
Preferably, the short-distance identification lens satisfies the following relation: 0.09< OAD <0.42 when DI <0.8 × MDI; TTL < 3.6; 75 ° < FOV <85 °; the OAD is the air distance between the third lens and the fourth lens on a straight line parallel to the optical axis but not the optical axis, the DI is the diameter of the third lens close to the aspheric surface of the image side surface and perpendicular to the direction of the optical axis, the MDI is the maximum effective diameter, the TTL is the distance between the object side surface of the first lens and the image surface on the optical axis, and the FOV is the maximum field angle of the short-distance identification lens.
Preferably, the short-distance identification lens satisfies the following relation: 0< T3-T1< 0.2; 0< T4-T2< 0.06; wherein, T1 is the distance on the optical axis from the object-side surface of the first lens element to the image-side surface of the first lens element, T2 is the distance on the optical axis from the object-side surface of the second lens element to the image-side surface of the second lens element, T3 is the distance on the optical axis from the object-side surface of the third lens element to the image-side surface of the third lens element, and T4 is the distance on the optical axis from the object-side surface of the fourth lens element to the image-side surface of the fourth lens element.
Preferably, the short-distance identification lens satisfies the following relation: 0< T3-SA6< 0.07; wherein T3 is the distance on the optical axis from the object-side surface of the third lens to the image-side surface of the third lens. SA6 is the distance from the center of the third lens image side aspheric surface to the maximum effective diameter in the direction parallel to the optical axis.
Preferably, the short-distance identification lens satisfies the following relation: 0.23< T1/∑ T < 0.3; 0.01< T2/∑ T < 0.25; 0.30< T3/∑ T < 0.45; 0.1< T4/∑ T < 0.23; Σ T is the sum of the optical axis thicknesses of the first lens, the second lens, the third lens, and the fourth lens on the optical axis, respectively, and T1, T2, T3, and T4 are the optical axis thicknesses of the first lens, the second lens, the third lens, and the fourth lens on the optical axis, respectively.
In general, compared with the prior art, the above technical solution contemplated by the present invention can achieve the following beneficial effects:
1. the short-distance identification lens is simple in structure, the lenses are made of plastic materials, tolerance sensitivity is low, and mass production is facilitated; the second lens has the largest focal length, so that high-order aberration can be corrected, and the aspheric surface shape of the second lens increases the light angle and the field angle; the first lens, the second lens, the third lens and the fourth lens are combined with each other to correct astigmatism and distortion, and simultaneously, the total length of the lens is reduced.
2. The short-distance identification lens is characterized in that the diaphragm is positioned between the object side surface of the first lens and a shot object and satisfies the following relational expression: 0< TDS/f1< 0.4; the total length of the lens is reduced, and the imaging quality is improved.
3. The close-range identification lens satisfies the relation: 0.09< OAD <0.42 when DI <0.8 × MDI; TTL < 3.6; 75 ° < FOV <85 °; 0< T3-SA6< 0.07; the air space between the third lens and the fourth lens is small, and the curvature of the image side surface of the third lens is large, so that astigmatism and distortion between the third lens and the fourth lens can be compensated with each other, aberration can be corrected, and imaging quality can be improved.
4. The close-range identification lens satisfies the relation: 0< T3-T1< 0.2; the center thicknesses of the front and rear groups of lenses are close to each other when the distance between the front and rear groups of lenses is 0< T4-T2<0.06, so that the spherical aberration of an imaging system is reduced.
5. The close-range identification lens satisfies the relation: 0.23< T1/∑ T < 0.3; 0.01< T2/∑ T < 0.25; 0.30< T3/∑ T < 0.45; 0.1< T4/∑ T < 0.23; the central thickness of the lens is controlled and the relational expression is satisfied, which is beneficial to correcting aberration, and the length of the lens is reduced to the maximum extent by combining the molding process of the plastic lens, thereby realizing the miniaturization of the short-distance identification lens.
[ description of the drawings ]
Fig. 1 is a schematic structural diagram of the short-range identification lens;
fig. 2 is a diagram of axial chromatic aberration (mm) of the short-range recognition lens;
FIG. 3 is an astigmatism diagram (mm) of the close-range identification lens;
fig. 4 is a distortion map (%) of the short-range recognition lens.
[ detailed description ] embodiments
In order to make the objects, technical solutions and advantages of the present invention more clearly understood, the present invention will be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
As shown in fig. 1, the short-distance recognition lens provided by the present invention includes a Stop (STO), a first lens (E1), a second lens (E2), a third lens (E3), a fourth lens (E4), and a chip protection glass (E5) sequentially arranged from an object plane to an image plane;
the first lens (E1) is a positive lens made of plastic, and the focal length of the first lens (E1) is 0.5< f1/f < 1.1; the object side surface is a convex surface and is an aspheric surface, and the image side surface is a convex surface and is an aspheric surface;
the second lens (E2) is a negative lens and is made of plastic, and the focal length meets the requirement that the focal length is-1.85 < f2/f < -1.52; the object side surface is a convex surface and is an aspheric surface, and the image side surface is a concave surface and is an aspheric surface;
the third lens (E3) is a positive lens made of plastic, and the focal length of the third lens (E3) is 0.52< f3/f < 1.2; the object side surface is a concave surface and is an aspheric surface, and the image side surface is a convex surface and is an aspheric surface;
the fourth lens (E4) is a negative lens made of plastic, and the focal length meets the requirement that the focal length is-0.8 < f4/f < 0; the object side surface is a convex surface and is an aspheric surface, and the image side surface is a convex surface and is an aspheric surface;
the close-range identification lens satisfies the relation: 1.28< TTL/f < 1.5;
wherein f1 is the effective focal length of the first lens element, f2 is the effective focal length of the second lens element, f3 is the effective focal length of the third lens element, f4 is the effective focal length of the fourth lens element, and TTL is the on-axis distance from the object-side surface of the first lens element to the image plane; f is the effective focal length of the close-range identification lens.
The second lens has a larger focal length and is beneficial to correcting high-order aberration. The first and second lenses, the third and fourth lenses, the negative and positive lenses are combined with each other to facilitate correction of astigmatism and distortion. By adjusting the power of each lens. The total length is reduced, and a larger angle of view is ensured on the basis of the total length.
Preferably, the close-range recognition lens satisfies the following relationship:
0.02<T12/f<0.03；
0.03<T34/f<0.04；
where T12 is an air space on the optical axis of the first lens and the second lens, and T34 is an air space on the optical axis of the third lens and the fourth lens.
The lens space of the close-range identification lens is small, and the total length of the system is reduced while the imaging quality is ensured.
Preferably, the stop is located between the object-side surface of the first lens and the object, and the close-range recognition lens satisfies the following relation:
0<TDS/f1<0.4；
wherein TDS is aperture diaphragm aperture, and f1 is first lens focal length.
The close-range identification lens has a smaller aperture coefficient, and is beneficial to improving the image quality and the overall brightness.
Preferably, the close-range recognition lens satisfies the following relationship:
0.09< OAD <0.42 when DI <0.8 × MDI;
TTL<3.6；
75°<FOV<85°；
the OAD is the air distance between the third lens and the fourth lens on a straight line parallel to the optical axis but not the optical axis, the DI is the diameter of the third lens close to the aspheric surface of the image side surface and perpendicular to the direction of the optical axis, the MDI is the maximum effective diameter, the TTL is the distance between the object side surface of the first lens and the image surface on the optical axis, and the FOV is the maximum field angle of the short-distance identification lens.
The third lens has larger curvature of the object side, which is beneficial to mutual compensation of astigmatism, distortion and the like between the third lens and the fourth lens, and improves the imaging quality. In addition, the short-distance recognition lens has a large angle of view, and the lens has a wider imaging range.
Preferably, the close-range recognition lens satisfies the following relationship:
0<T3-T1<0.11；
0<T4-T2<0.06；
wherein, T1 is the distance on the optical axis from the object-side surface of the first lens element to the image-side surface of the first lens element, T2 is the distance on the optical axis from the object-side surface of the second lens element to the image-side surface of the second lens element, T3 is the distance on the optical axis from the object-side surface of the third lens element to the image-side surface of the third lens element, and T4 is the distance on the optical axis from the object-side surface of the fourth lens element to the image-side surface of the fourth lens element.
The center thicknesses of the front and the rear groups of lenses are close, which is beneficial to reducing the spherical aberration of the lens.
Preferably, the close-range recognition lens satisfies the following relationship:
0<T3-SA6<0.07；
wherein T3 is the distance on the optical axis from the object-side surface of the third lens to the image-side surface of the third lens. SA6 is the distance from the center of the third lens image side aspheric surface to the maximum effective diameter in the direction parallel to the optical axis.
The difference value of the two is small, so that distortion and astigmatism can be mainly generated on the image side surface of the third lens, the structure of the fourth lens is optimally controlled to perform mutual compensation, and the imaging quality of the marginal field of view is favorably improved.
Preferably, the close-range recognition lens satisfies the following relationship:
0.23<T1/∑T<0.3；
0.01<T2/∑T<0.25；
0.30<T3/∑T<0.45；
0.1<T4/∑T<0.23；
Σ T is the sum of the optical axis thicknesses of the first lens, the second lens, the third lens, and the fourth lens on the optical axis, respectively, and T1, T2, T3, and T4 are the optical axis thicknesses of the first lens, the second lens, the third lens, and the fourth lens on the optical axis, respectively. The thickness of each lens is controlled within the range, so that aberration correction and mutual compensation are facilitated, tolerance sensitivity can be reduced, and difficulty in the molding process can be reduced. Meanwhile, the total length of the lens is reduced, and the ultrathin and miniaturization of the lens are realized.
The following table is a table of lens data for the examples
Table 1 shows the structural parameters of the short-distance identification lens
TABLE 1
Table 2 shows the range of the ratio of the aspherical rise to the radius R of each of the first lens E1 and the second lens E2
TABLE 2
Table 3 shows the range of the ratio of the aspherical rise to the radius R of each of the third lens E3 and the fourth lens E4
TABLE 3
Claims (7)
1. Closely discernment camera lens, its characterized in that: a diaphragm (STO), a first lens (E1), a second lens (E2), a third lens (E3), a fourth lens (E4) and chip protective glass (E5) are arranged in sequence from an object plane to an image plane;
the first lens (E1) is a positive lens made of plastic, and the focal length of the first lens (E1) is 0.5< f1/f < 1.1; the object side surface is a convex surface and is an aspheric surface, and the image side surface is a convex surface and is an aspheric surface;
the second lens (E2) is a negative lens and is made of plastic, and the focal length meets the requirement that the focal length is-1.85 < f2/f < -1.52; the object side surface is a convex surface and is an aspheric surface, and the image side surface is a concave surface and is an aspheric surface;
the third lens (E3) is a positive lens made of plastic, and the focal length of the third lens (E3) is 0.52< f3/f < 1.2; the object side surface is a concave surface and is an aspheric surface, and the image side surface is a convex surface and is an aspheric surface;
the fourth lens (E4) is a negative lens made of plastic, and the focal length meets the requirement that the focal length is-0.8 < f4/f < 0; the object side surface is a convex surface and is an aspheric surface, and the image side surface is a convex surface and is an aspheric surface;
the close-range identification lens satisfies the following relational expression: 1.28< TTL/f < 1.5;
wherein f1 is the effective focal length of the first lens element, f2 is the effective focal length of the second lens element, f3 is the effective focal length of the third lens element, f4 is the effective focal length of the fourth lens element, and TTL is the on-axis distance from the object-side surface of the first lens element to the image plane; f is the effective focal length of the close-range identification lens.
2. The close-up recognition lens according to claim 1, wherein the following relation is satisfied:
0.02<T12/f<0.03；
0.03<T34/f<0.04；
where T12 is an air space on the optical axis of the first lens and the second lens, and T34 is an air space on the optical axis of the third lens and the fourth lens.
3. The close-range recognition lens of claim 1, wherein the stop is located between the object-side surface of the first lens and the subject, and satisfies the following relationship:
0<TDS/f1<0.4；
wherein TDS is aperture diaphragm aperture, and f1 is first lens focal length.
4. The close-up recognition lens according to claim 1, wherein the following relation is satisfied:
0.09< OAD <0.42 when DI <0.8 × MDI;
TTL<3.6；
75°<FOV<85°；
the OAD is the air distance between the third lens and the fourth lens on a straight line parallel to the optical axis but not the optical axis, the DI is the diameter of the third lens close to the aspheric surface of the image side surface and perpendicular to the direction of the optical axis, the MDI is the maximum effective diameter, the TTL is the distance between the object side surface of the first lens and the image surface on the optical axis, and the FOV is the maximum field angle of the short-distance identification lens.
5. The close-up recognition lens according to claim 1, wherein the following relation is satisfied:
0<T3-T1<0.2；
0<T4-T2<0.06；
wherein, T1 is the distance on the optical axis from the object-side surface of the first lens element to the image-side surface of the first lens element, T2 is the distance on the optical axis from the object-side surface of the second lens element to the image-side surface of the second lens element, T3 is the distance on the optical axis from the object-side surface of the third lens element to the image-side surface of the third lens element, and T4 is the distance on the optical axis from the object-side surface of the fourth lens element to the image-side surface of the fourth lens element.
6. The close-up recognition lens according to claim 1, wherein the following relation is satisfied:
0<T3-SA6<0.07；
wherein, T3 is the distance on the optical axis from the object side surface to the image side surface of the third lens, and SA6 is the distance parallel to the optical axis from the center of the aspheric surface of the image side surface of the third lens to the maximum effective diameter.
7. The close-up recognition lens according to claim 1, wherein the following relation is satisfied:
0.23<T1/∑T<0.3；
0.01<T2/∑T<0.25；
0.30<T3/∑T<0.45；
0.1<T4/∑T<0.23；
Σ T is the sum of the optical axis thicknesses of the first lens, the second lens, the third lens, and the fourth lens on the optical axis, respectively, and T1, T2, T3, and T4 are the optical axis thicknesses of the first lens, the second lens, the third lens, and the fourth lens on the optical axis, respectively.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022293637.8U CN212515191U (en) | 2020-10-16 | 2020-10-16 | Short-distance identification lens |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022293637.8U CN212515191U (en) | 2020-10-16 | 2020-10-16 | Short-distance identification lens |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN212515191U true CN212515191U (en) | 2021-02-09 |
Family
ID=74390147
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202022293637.8U Active CN212515191U (en) | 2020-10-16 | 2020-10-16 | Short-distance identification lens |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN212515191U (en) |
-
2020
- 2020-10-16 CN CN202022293637.8U patent/CN212515191U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106501921B (en) | Unmanned aerial vehicle camera lens | |
| CN108693632A (en) | A kind of miniature wide-angle imaging lens optical system | |
| CN111722369A (en) | Ultra-wide angle lens | |
| CN208818918U (en) | A kind of novel wide-angle imaging lens optical system | |
| CN108614344B (en) | Vehicle-mounted wide-angle lens | |
| CN209746255U (en) | Small-head type high-pixel glass-plastic hybrid lens | |
| WO2023109491A1 (en) | Vehicle-mounted lens | |
| CN212515191U (en) | Short-distance identification lens | |
| CN114047597B (en) | Fixed focus optical lens and imaging method thereof | |
| CN109425963B (en) | Optical lens | |
| CN216285930U (en) | Fixed focus lens | |
| CN108761738A (en) | A kind of high pixel ultrathin type mobile lens optical system | |
| CN212623307U (en) | Two-lens small-diameter large-field-angle lens | |
| CN213544944U (en) | Optical imaging lens | |
| CN212229309U (en) | Optical imaging lens used for matching with liquid lens | |
| CN112083558A (en) | Short-distance identification lens | |
| CN111352213B (en) | Periscope type lens with high-pixel prism | |
| CN209946507U (en) | Full-color night-vision inner focusing lens | |
| CN208569165U (en) | A kind of mobile lens optical system | |
| CN112130296A (en) | Small-size closely discernment camera lens | |
| CN219512464U (en) | Industrial bar code recognition lens | |
| CN112230392A (en) | Wide-angle high-resolution lens | |
| CN207937677U (en) | A kind of mobile phone imaging lens | |
| CN112415727A (en) | Be used for commercial car driving big light ring high definition camera lens night | |
| CN112014948A (en) | Long-focus imaging optical system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |