Wide-angle imaging lens

文档序号:1413725 发布日期:2020-03-10 浏览:2次 中文

阅读说明:本技术 广角成像镜头 (Wide-angle imaging lens ) 是由 谢典良 于 2018-09-14 设计创作,主要内容包括:本发明公开了一种广角成像镜头,从物侧至像侧沿一光轴依序包括一第一透镜、一第二透镜、一光圈、一第三透镜、一第四透镜及一第五透镜。第一透镜至第五透镜的屈光度依序为负、正、正、负、正。第一透镜的物侧面的光轴附近区域为凹面,第一透镜的像侧面为凹面。第二透镜的物侧面为凸面。第三透镜的物侧面为凸面。第三透镜的像侧面为凸面。第四透镜的物侧面为凹面。第四透镜的像侧面具有一位于光轴附近区域的凹面部。第五透镜的像侧面为凸面。(The invention discloses a wide-angle imaging lens which sequentially comprises a first lens, a second lens, an aperture, a third lens, a fourth lens and a fifth lens from an object side to an image side along an optical axis. Diopters of the first lens to the fifth lens are negative, positive, negative and positive in sequence. The area near the optical axis of the object side surface of the first lens is a concave surface, and the image side surface of the first lens is a concave surface. The object side surface of the second lens is a convex surface. The object side surface of the third lens is a convex surface. The image side surface of the third lens is convex. The object side surface of the fourth lens is a concave surface. The image side surface of the fourth lens is provided with a concave surface part which is positioned in the area near the optical axis. The image side surface of the fifth lens is convex.)

1. A wide-angle imaging lens is characterized by comprising a first lens, a second lens, an aperture, a third lens, a fourth lens and a fifth lens in sequence from an object side to an image side along an optical axis, wherein the first lens to the fifth lens respectively comprise an object side surface facing the object side and allowing imaging light rays to pass through and an image side surface facing the image side and allowing the imaging light rays to pass through, and the lenses with diopter only comprise the five lenses;

the first lens is provided with negative diopter, the area near the optical axis of the object side surface of the first lens is a concave surface, and the image side surface of the first lens is a concave surface;

the second lens has positive diopter, and the object side surface of the second lens is a convex surface;

the third lens element has a positive refractive power, the object-side surface of the third lens element is a convex surface, and the image-side surface of the third lens element is a convex surface;

the fourth lens has negative diopter, the object side surface of the fourth lens is a concave surface, and the image side surface of the fourth lens is provided with a concave surface part positioned in an area near an optical axis; and

the fifth lens element has a positive refractive power, and the image-side surface of the fifth lens element is convex.

2. The wide-angle imaging lens of claim 1, wherein the wide-angle imaging lens conforms to: -0.8 ≦ EFL/R1<0, where EFL is the effective focal length of the wide-angle imaging lens and R1 is the radius of curvature of the object-side surface of the first lens.

3. The wide-angle imaging lens of claim 1, wherein the wide-angle imaging lens conforms to: 0.8 ≦ EFL/f1 ≦ 1.2, where EFL is an effective focal length of the wide-angle imaging lens, f1 is a focal length of the first lens, and | EFL/f1| is an absolute value of EFL/f 1.

4. The wide-angle imaging lens of claim 1, wherein the wide-angle imaging lens conforms to: -3.0 ≦ (R3+ R4)/(R3-R4) ≦ 0.9, where R3 is the radius of curvature of the object-side surface of the second lens and R4 is the radius of curvature of the image-side surface of the second lens.

5. The wide-angle imaging lens of claim 1, wherein a range of an angle of view of the wide-angle imaging lens falls within a range of 130 degrees to 150 degrees.

6. The wide-angle imaging lens according to claim 1, wherein, of the first lens, the second lens, the third lens, the fourth lens and the fifth lens having refractive power, the refractive index of the second lens is equal to or greater than the refractive index of the other lenses having refractive power, and the abbe number of the second lens is equal to or less than the abbe number of the other lenses having refractive power.

7. The wide-angle imaging lens of claim 1,

the object side surface of the first lens is a concave surface and is provided with a concave surface part positioned in the area near the circumference,

the image side surface of the second lens is convex,

the image side surface of the fourth lens is provided with a concave surface part positioned in an area near an optical axis and a convex surface part positioned in an area near the circumference,

the object side surface of the fifth lens is provided with a convex surface part positioned in an area near an optical axis and a concave surface part positioned in an area near the circumference.

8. The wide-angle imaging lens of claim 1,

the object side surface of the first lens is provided with a convex surface part positioned in the area near the circumference,

the image side surface of the second lens is convex,

the image side surface of the fourth lens is provided with a concave surface part positioned in an area near an optical axis and a convex surface part positioned in an area near the circumference,

the object side surface of the fifth lens is provided with a convex surface part positioned in an area near an optical axis and a concave surface part positioned in an area near the circumference.

9. The wide-angle imaging lens of claim 1,

the object side surface of the first lens is a concave surface and is provided with a concave surface part positioned in the area near the circumference,

the image side surface of the second lens is convex,

the image side surface of the fourth lens is a concave surface and is provided with a concave surface part positioned in the area near the circumference,

the object side surface of the fifth lens is a convex surface.

10. The wide-angle imaging lens of claim 1,

the object side surface of the first lens is a concave surface and is provided with a concave surface part positioned in the area near the circumference,

the image side surface of the second lens is a concave surface,

the image side surface of the fourth lens is provided with a concave surface part positioned in an area near an optical axis and a convex surface part positioned in an area near the circumference,

the object side surface of the fifth lens is a concave surface.

Technical Field

The present invention relates to an optical imaging lens, and more particularly to a wide-angle imaging lens.

Background

In recent years, the popularity of mobile phones and digital cameras has led to the development of camera modules, and wide-angle imaging lenses for capturing and recording images are required to be designed to be light, thin, small and compact. However, the wide-angle imaging lens in the present stage generally has a long lens Length (TTL), which is not favorable for thinning the lens. In view of the above problems, it is an endeavor of those skilled in the art to design an imaging lens having a good imaging quality, a short lens length, and a wide angle of view.

Disclosure of Invention

The invention provides a wide-angle imaging lens which has a wide visual angle, a short lens length and good optical quality.

In an embodiment of the present invention, a wide-angle imaging lens includes, in order from an object side to an image side along an optical axis, a first lens element, a second lens element, an aperture stop, a third lens element, a fourth lens element and a fifth lens element. The first lens element to the fifth lens element each include an object-side surface facing the object side and passing the imaging light and an image-side surface facing the image side and passing the imaging light, and the lens elements having refractive power are only the five lens elements. The first lens has a negative refractive power. The area near the optical axis of the object side surface of the first lens is a concave surface, and the image side surface of the first lens is a concave surface. The second lens has a positive refractive power. The object side surface of the second lens is a convex surface. The third lens has a positive refractive power. The object side surface of the third lens is a convex surface. The image side surface of the third lens is convex. The fourth lens has a negative refractive power. The object side surface of the fourth lens is a concave surface. The image side surface of the fourth lens is provided with a concave surface part which is positioned in the area near the optical axis. The fifth lens element has a positive refractive power, and an image-side surface of the fifth lens element is convex.

In an embodiment of the present invention, the wide-angle imaging lens includes: -0.8 ≦ EFL/R1<0, where EFL is the effective focal length of the wide-angle imaging lens and R1 is the radius of curvature of the object side of the first lens.

In an embodiment of the present invention, the wide-angle imaging lens includes: 0.8 ≦ EFL/f1 ≦ 1.2, where EFL is an effective focal length of the wide-angle imaging lens, f1 is a focal length of the first lens, and | EFL/f1| is an absolute value of EFL/f 1.

In an embodiment of the present invention, the wide-angle imaging lens includes: -3.0 ≦ (R3+ R4)/(R3-R4) ≦ 0.9, where R3 is the radius of curvature of the object-side surface of the second lens, and R4 is the radius of curvature of the image-side surface of the second lens.

In an embodiment of the invention, a range of the field angle of the wide-angle imaging lens is in a range of 130 degrees to 150 degrees.

In an embodiment of the invention, in the first lens, the second lens, the third lens, the fourth lens and the fifth lens having diopter, the refractive index of the second lens is greater than or equal to the refractive index of the other lenses having diopter, and the abbe number of the second lens is less than or equal to the abbe number of the other lenses having diopter.

In an embodiment of the invention, the object-side surface of the first lens element is concave and has a concave portion located in a region near the circumference. The image side surface of the second lens is convex. The image side surface of the fourth lens is provided with a concave surface part positioned in an area nearby an optical axis and a convex surface part positioned in an area nearby the circumference. The object side surface of the fifth lens is provided with a convex surface part positioned in an area near an optical axis and a concave surface part positioned in an area near the circumference.

In an embodiment of the invention, the object-side surface of the first lens element has a convex surface portion located in a circumferential vicinity. The image side surface of the second lens is convex. The image side surface of the fourth lens is provided with a concave surface part positioned in an area nearby an optical axis and a convex surface part positioned in an area nearby the circumference. The object side surface of the fifth lens is provided with a convex surface part positioned in an area near an optical axis and a concave surface part positioned in an area near the circumference.

In an embodiment of the invention, the object-side surface of the first lens element is concave and has a concave portion located in a region near the circumference. The image side surface of the second lens is convex. The image side surface of the fourth lens is concave and is provided with a concave surface part positioned in the area near the circumference. The object side surface of the fifth lens is a convex surface.

In an embodiment of the invention, the object-side surface of the first lens element is concave and has a concave portion located in a region near the circumference. The image side surface of the second lens is a concave surface. The image side surface of the fourth lens is provided with a concave surface part positioned in an area nearby an optical axis and a convex surface part positioned in an area nearby the circumference. The object side surface of the fifth lens is a concave surface.

Based on the above, the wide-angle imaging lens of the embodiment of the invention has the following beneficial effects: by the concave-convex shape design and arrangement of the object side surface or the image side surface of the lens and the diopter combination of the lens, the wide-angle imaging lens can achieve the effect of wide visual angle, shorter lens length and good imaging quality.

In order to make the aforementioned and other features and advantages of the invention more comprehensible, embodiments accompanied with figures are described in detail below.

Drawings

Fig. 1 is a schematic diagram of a wide-angle imaging lens according to a first embodiment of the present invention.

Fig. 2A to 2D are longitudinal spherical aberration diagrams and various aberration diagrams of the first embodiment.

Fig. 3 is a schematic diagram of a wide-angle imaging lens according to a second embodiment of the present invention.

Fig. 4A to 4D are longitudinal spherical aberration diagrams and various aberration diagrams of the second embodiment.

Fig. 5 is a schematic diagram of a wide-angle imaging lens according to a third embodiment of the present invention.

Fig. 6A to 6D are longitudinal spherical aberration diagrams and various aberration diagrams of the third embodiment.

Fig. 7 is a schematic diagram of a wide-angle imaging lens according to a fourth embodiment of the present invention.

Fig. 8A to 8D are longitudinal spherical aberration diagrams and various aberration diagrams of the fourth embodiment.

Wherein, the reference numbers:

0: aperture

1: first lens

2: second lens

3: third lens

4: fourth lens

5: fifth lens element

9: optical filter

11. 21, 31, 41, 51, 91: side of the object

12. 22, 32, 42, 52, 92: image side

112. 114, 122, 124, 222, 224, 412, 414, 422, 424, 512, 514: concave part

113. 211, 213, 221, 223, 311, 313, 321, 323, 423, 511, 513, 521, 523: convex surface part

10: wide-angle imaging lens

100: image plane

Ef1、Ef2: outer edge of optically effective portion

Ei: outer edge of optically inactive portion

I: optical axis

RP1, RP 2: reference plane

Pn: optical null

θ: included angle

Detailed Description

In the present specification, "a lens has a positive refractive power (or a negative refractive power)" means that the refractive power on the optical axis of the lens calculated by the gaussian optical theory is positive (or negative). In the imaging lens group, each lens is radially symmetrical with each other by taking the optical axis as a symmetry axis. Each lens has an object side surface and an image side surface opposite to the object side surface. The object-side surface and the image-side surface define surfaces of the lens through which imaging light rays pass, wherein the imaging light rays include a chief ray (Chief ray) and a marginal ray (marginalray). The object side surface (or image side surface) has an optical axis vicinity region and a circumference vicinity region connected to and surrounding the optical axis vicinity region. The region near the optical axis is a region on the optical axis through which the imaging light passes. The peripheral vicinity is a region through which the marginal ray passes.

"a region of a surface (an object-side surface or an image-side surface) of the lens near the optical axis (or a region near the circumference thereof) is a convex surface or a concave surface" may be determined on the image side or the object side by an intersection point of a ray (or a ray extension line) passing through the region in parallel with the optical axis (a ray focus determination method). For example, when the light passes through the region, the light is focused toward the image side, and the focal point of the optical axis is located at the image side, the region is a convex surface portion. On the contrary, if the light passes through the certain region, the light diverges, and the extension line and the focal point of the optical axis are on the object side. The determination of the surface shape of the surface in the region near the optical axis can be made according to the determination manner of a person skilled in the art, that is, the determination of the unevenness is made by the positive or negative of the R value (referring to the curvature radius of the paraxial region). Regarding the object side, when the R value is positive, it is determined that the object side is convex in the area near the optical axis, that is, the object side has a convex portion in the area near the optical axis; when the value of R is negative, it is determined that the object side surface has a concave surface in the region near the optical axis, that is, the object side surface has a concave surface portion in the region near the optical axis. Regarding the image side surface, when the R value is positive, it is determined that the image side surface is concave in the region near the optical axis, that is, the image side surface has a concave portion in the region near the optical axis; when the R value is negative, it is determined that the image side surface is convex in the region near the optical axis, that is, the image side surface has a convex portion in the region near the optical axis.

A surface (object side or image side) of the lens may have more than one convex portion, more than one concave portion, or a combination of both. When the surface has a convex surface portion and a concave surface portion, the surface has an inflection point. The inflection point is the transition point between the convex surface portion and the concave surface portion. That is, the surface is concave by convex, or convex by concave at points of reverse curvature. On the other hand, when the surface has only a convex surface portion or only a concave surface portion, the surface does not have an inflection point.

Referring to fig. 1, a wide-angle imaging lens 10 according to the first embodiment of the present invention includes, in order along an optical axis I, a first lens element 1, a second lens element 2, an aperture stop 0, a third lens element 3, a fourth lens element 4, a fifth lens element 5 and a filter 9. The object side is a side facing an object to be photographed, and the Image side is a side facing an Image Plane (Image Plane) 100. After entering the wide-angle imaging lens 10, light emitted from an object to be photographed sequentially passes through the first lens 1, the second lens 2, the aperture 0, the third lens 3, the fourth lens 4, the fifth lens 5, and the optical filter 9, and then forms an image on the imaging surface 100. The filter 9 is, for example, an infrared cut filter (ir filter) for preventing infrared rays in a partial band of light from being transmitted to the image plane 100 to affect the image quality, but the invention is not limited thereto.

The first lens element 1, the second lens element 2, the third lens element 3, the fourth lens element 4, the fifth lens element 5, and the filter 9 each include an object- side surface 11, 21, 31, 41, 51, 91 facing the object side and through which the imaging light passes, and an image- side surface 12, 22, 32, 42, 52, 92 facing the image side and through which the imaging light passes.

The first lens 1 has a negative refractive power. The object side surface 11 of the first lens element 1 is concave, and has a concave portion 112 located in the vicinity of the optical axis and a concave portion 114 located in the vicinity of the circumference. The image-side surface 12 of the first lens element 1 is concave, and has a concave portion 122 located in the vicinity of the optical axis and a concave portion 124 located in the vicinity of the circumference.

The second lens 2 has a positive refractive power. The object-side surface 21 of the second lens element 2 is convex, and has a convex surface 211 located in the vicinity of the optical axis and a convex surface 213 located in the vicinity of the circumference. The image-side surface 22 of the second lens element 2 is convex, and has a convex portion 221 located in the vicinity of the optical axis and a convex portion 223 located in the vicinity of the circumference.

The diaphragm 0 is disposed between the second lens 2 and the third lens 3.

The third lens 3 has a positive refractive power. The object-side surface 31 of the third lens element 3 is convex, and has a convex portion 311 located in the vicinity of the optical axis and a convex portion 313 located in the vicinity of the circumference. The image-side surface 32 of the third lens element 3 is convex, and has a convex portion 321 located in the vicinity of the optical axis and a convex portion 323 located in the vicinity of the circumference.

The fourth lens 4 has a negative refractive power. The object side surface 41 of the fourth lens element 4 is concave, and has a concave portion 412 located in the vicinity of the optical axis and a concave portion 414 located in the vicinity of the circumference. The image-side surface 42 of the fourth lens element 4 has a concave portion 422 located in the vicinity of the optical axis and a convex portion 423 located in the vicinity of the circumference.

The fifth lens 5 has a positive refractive power. The object-side surface 51 of the fifth lens element 5 has a convex surface portion 511 located in the vicinity of the optical axis and a concave surface portion 514 located in the vicinity of the circumference. The image-side surface 52 of the fifth lens element 5 is convex, and has a convex portion 521 located in the vicinity of the optical axis and a convex portion 523 located in the vicinity of the circumference.

In the wide-angle imaging lens 10 of the present embodiment, only the above five lenses having refractive powers are present. In addition, in the embodiment, the first lens element 1 to the fifth lens element 5 may be made of plastic material to satisfy the requirement of light weight, but not limited thereto. In another example, the first lens element 1 to the fifth lens element 5 may be made of glass. In another example, at least one of the first lens 1 to the fifth lens 5 may be made of a glass material, and the remaining lenses may be made of a plastic material.

Other detailed optical data for the first embodiment are shown in table one. In table I, a distance (mm) between the object-side surface 11 of the first lens element 1 and the image-side surface 12 of the first lens element 1 is 0.200mm, which means that the distance between the object-side surface 11 of the first lens element 1 and the image-side surface 12 of the first lens element 1 on the optical axis I (i.e. the thickness of the first lens element 1 on the optical axis I) is 0.200 mm. A distance (mm) of 0.193 from the image-side surface 12 of the first lens 1 represents that the distance from the image-side surface 12 of the first lens 1 to the object-side surface 21 of the second lens 2 on the optical axis I is 0.193 mm. The other fields of the pitch (mm) can be analogized and will not be repeated below.

Figure BDA0001800362410000061

Watch 1

In the present embodiment, the object- side surfaces 11, 21, 31, 41, 51 and the image- side surfaces 12, 22, 32, 42, 52 of the first lens element 1, the second lens element 2, the third lens element 3, the fourth lens element 4 and the fifth lens element 5 are all aspheric surfaces, and these aspheric surfaces are defined by the following formula (1):

in the formula (1), Y is a distance between a point on the aspherical surface curve and the optical axis I. Z is the depth of the aspheric surface. R is the radius of curvature of the lens surface near the optical axis I. K is the cone constant (conc constant). A. theiAre the i-th order aspheric coefficients.

The aspheric coefficients of the object-side surface 11 of the first lens 1 to the image-side surface 52 of the fifth lens 5 in formula (1) are shown in table two. In the second table, the column number 11 indicates that it is the aspheric coefficient of the object-side surface 11 of the first lens element 1, and so on.

Figure BDA0001800362410000072

Figure BDA0001800362410000081

Watch two

The relationship between the important parameters in the wide-angle imaging lens 10 of the first embodiment is shown in table three.

Effective Focal Length (EFL) 0.40 mm (mm)
Half field angle (HFOV) 71.0 degree
Lens full length (TTL) 2.328 mm (mm)
Aperture value (f-number) 5.00
EFL/R1 -0.08
|EFL/f1| 0.88
(R3+R4)/(R3-R4) -0.82

Watch III

The wide-angle imaging lens 10 of the first embodiment has an Effective Focal Length (EFL) of 0.40 mm. The Half field Angle (HFOV) is 71.0 degrees. Total Track Length (TTL) is a distance on the optical axis I from the object side surface 11 of the first lens element 1 to the image forming surface 100, and is 2.328 mm. The aperture value (f-number) was 5.00. EFL/R1 is-0.08, where R1 is the radius of curvature of the object side 11 of the first lens 1. I EFL/f1 is 0.88, where f1 is the focal length of the first lens 1. (R3+ R4)/(R3-R4) is-0.82, where R3 is the radius of curvature of the object-side surface 21 of the second lens 2 and R4 is the radius of curvature of the image-side surface 22 of the second lens 2.

Referring to fig. 2A to 2D, the diagram of fig. 2A illustrates the Longitudinal Spherical Aberration (Longitudinal Spherical Aberration) of the first embodiment at the imaging plane 100 when the wavelengths 656 nm, 587 nm and 486 nm. Fig. 2B and fig. 2C are diagrams illustrating Field Curvature (Field Curvature) aberration in Sagittal (Sagittal) direction and Field Curvature aberration in Tangential (Tangential) direction of the first embodiment at a wavelength of 587 nm on the imaging plane 100, respectively. The diagram of fig. 2D illustrates the Distortion Aberration (Aberration) on the imaging plane 100 when the wavelength is 587 nm in the first embodiment.

Referring to fig. 2A again, the curves formed by each wavelength are very close and close to the middle, which shows that the off-axis light beams with different heights of each wavelength are all concentrated near the imaging point, and the deviation of the off-axis light beams with different heights is controlled within the range of ± 0.01 mm as can be seen from the deviation of the curve of each wavelength, so that the spherical aberration of the same wavelength is obviously improved in the first embodiment.

In the two field curvature aberration diagrams of fig. 2B and fig. 2C, the variation of the focal length of 587 nm wavelength over the entire field of view is within ± 0.01 mm, which illustrates that the first embodiment can effectively eliminate the aberration. The distortion aberration diagram of fig. 2D shows that the distortion aberration of the first embodiment is maintained within a range of ± 50%, which indicates that the distortion aberration of the first embodiment meets the requirement of the optical system for image quality, and thus the first embodiment can provide good image quality under the condition that the total lens length is shortened to about 2.328 mm compared with the conventional optical lens.

Fig. 3 is a schematic diagram of a wide-angle imaging lens according to a second embodiment of the present invention. Fig. 4A to 4D are longitudinal spherical aberration diagrams and various aberration diagrams of the second embodiment. Referring to fig. 3, a second embodiment of the wide-angle imaging lens 10 of the present invention is substantially similar to the first embodiment, and the difference between the two embodiments is as follows: the optical data, aspherical coefficients and parameters between these lenses 1, 2, 3, 4 and 5 are more or less different. In addition, the object side surface 11 of the first lens element 1 has a concave portion 112 located in the vicinity of the optical axis and a convex portion 113 located in the vicinity of the circumference. Note here that, in order to clearly show the drawing, reference numerals of the optical axis vicinity region and the circumference vicinity region, which are similar to the irregularities of the first embodiment, are omitted in fig. 3.

Other detailed optical data for the second embodiment are shown in table four below. The aspheric coefficients of the terms in equation (1) for the object-side surface 11 of the first lens 1 to the image-side surface 52 of the fifth lens 5 of the second embodiment are shown in table five:

Figure BDA0001800362410000091

watch four

Figure BDA0001800362410000102

Figure BDA0001800362410000111

Watch five

The relationship between the important parameters in the wide-angle imaging lens 10 of the second embodiment is shown in table six.

Effective Focal Length (EFL) 0.38 mm (mm)
Half field angle (HFOV) 70.0 degree
Lens full length (TTL) 2.650 mm (mm)
Aperture value (f-number) 4.50
EFL/R1 -0.71
|EFL/f1| 0.81
(R3+R4)/(R3-R4) 0.76

Watch six

In the diagram of FIG. 4A, the deviation of the imaging points of the off-axis light rays with different heights is controlled within + -0.025 mm. In the two graphs of field curvature aberration of fig. 4B and 4C, the variation of focal length of three representative wavelengths in the entire field of view is within ± 0.025 mm. The distortion aberration diagram of FIG. 4D shows that the distortion aberration of the second embodiment is maintained within a range of + -40%. Accordingly, the wide-angle imaging lens 10 of the second embodiment has good optical imaging quality under the condition that the total lens length is shortened to about 2.650 mm.

Fig. 5 is a schematic diagram of a wide-angle imaging lens according to a third embodiment of the present invention. Fig. 6A to 6D are longitudinal spherical aberration diagrams and various aberration diagrams of the third embodiment. Referring to fig. 5, a third embodiment of the wide-angle imaging lens 10 of the present invention is substantially similar to the first embodiment, and the difference between the two embodiments is as follows: the optical data, aspherical coefficients and parameters between these lenses 1, 2, 3, 4 and 5 are more or less different. The image-side surface 42 of the fourth lens element 4 is concave, and has a concave portion 422 located in the vicinity of the optical axis and a concave portion 424 located in the vicinity of the circumference. The object-side surface 51 of the fifth lens element 5 is convex, and has a convex portion 511 located in the vicinity of the optical axis and a convex portion 513 located in the vicinity of the circumference. Note here that, in order to clearly show the drawing, reference numerals of the optical axis vicinity region and the circumference vicinity region, which are similar to the irregularities of the first embodiment, are omitted in fig. 5.

Other detailed optical data of the third embodiment are shown in table seven below. Each aspheric coefficient of the object side surface 11 of the first lens 1 to the image side surface 52 of the fifth lens 5 in the formula (1) of the third embodiment is as shown in table eight.

Figure BDA0001800362410000121

Watch seven

Figure BDA0001800362410000122

Figure BDA0001800362410000131

Table eight

The relationship between the important parameters in the wide-angle imaging lens 10 of the third embodiment is shown in table nine.

Effective Focal Length (EFL) 0.47 mm (mm)
Half field angle (HFOV) 70.0 degree
Lens full length (TTL) 2.483 mm (mm)
Aperture value (f-number) 4.40
EFL/R1 -0.67
|EFL/f1| 0.99
(R3+R4)/(R3-R4) 0.90

Watch nine

In the diagram of fig. 6A, the deviation of the imaging points of the off-axis light rays with different heights is controlled within ± 0.01 mm. In the two graphs of field curvature aberration of fig. 6B and 6C, the variation of focal length of the three representative wavelengths over the entire field of view falls within ± 0.01 mm. The distortion aberration diagram of FIG. 6D shows that the distortion aberration of the third embodiment is maintained within a range of + -50%. Accordingly, the wide-angle imaging lens 10 of the third embodiment has good optical imaging quality under the condition that the total lens length is shortened to about 2.483 mm.

Fig. 7 is a schematic diagram of a wide-angle imaging lens according to a fourth embodiment of the present invention. Fig. 8A to 8D are longitudinal spherical aberration diagrams and various aberration diagrams of the fourth embodiment. Referring to fig. 7, a fourth embodiment of the wide-angle imaging lens assembly 10 of the present invention is substantially similar to the first embodiment, and the difference between the two embodiments is as follows: the optical data, aspherical coefficients and parameters between these lenses 1, 2, 3, 4 and 5 are more or less different. The image-side surface 22 of the second lens element 2 is concave, and has a concave portion 222 located in the vicinity of the optical axis and a concave portion 224 located in the vicinity of the circumference. The object side surface 51 of the fifth lens element 5 is concave, and has a concave portion 512 located in the vicinity of the optical axis and a concave portion 514 located in the vicinity of the circumference. Note here that, in order to clearly show the drawing, reference numerals of the optical axis vicinity region and the circumference vicinity region, which are similar to the irregularities of the first embodiment, are omitted in fig. 7.

Other detailed optical data of the fourth embodiment are shown in the following table ten. The aspheric coefficients of the terms in equation (1) for the object-side surface 11 of the first lens 1 to the image-side surface 52 of the fifth lens 5 of the fourth embodiment are shown in table eleven.

Figure BDA0001800362410000141

Watch ten

Surface of K A4 A6 A8
11 -9.9000E+01 4.3004E-01 -2.0093E+00 1.1862E+00
12 -1.1672E+00 -2.5559E+00 9.7652E+01 8.9671E+01
21 -3.2680E+01 4.6320E+00 -1.5628E+01 -2.0898E+02
22 4.0674E+01 3.2007E-01 -1.6251E+02 3.5683E+04
31 3.2996E+00 -5.0175E+00 8.1882E+01 -7.7727E+03
32 -9.7119E+00 -2.1234E+01 8.4775E+02 -2.2295E+04
41 -1.6901E+01 -1.2895E+01 5.1420E+02 -1.9108E+04
42 -9.9000E+01 -2.8205E+00 -9.9542E+01 4.4210E+03
51 8.5999E+01 1.3451E+01 -6.3835E+02 1.4257E+04
52 7.7560E-01 1.5730E+01 -1.8597E+02 1.2508E+03
Noodle A10 A12 A14 A16
11 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00
12 -8.3965E+03 0.0000E+00 0.0000E+00 0.0000E+00
21 5.7819E+03 -5.3084E+04 0.0000E+00 0.0000E+00
22 -2.5561E+06 7.0932E+07 0.0000E+00 0.0000E+00
31 2.8162E+05 0.0000E+00 0.0000E+00 0.0000E+00
32 3.6267E+05 0.0000E+00 0.0000E+00 0.0000E+00
41 3.3218E+05 -1.5510E+06 0.0000E+00 0.0000E+00
42 -6.1367E+04 2.6939E+05 0.0000E+00 0.0000E+00
51 -1.6621E+05 1.0103E+06 -2.8394E+06 0.0000E+00
52 -8.3141E+01 -3.7712E+04 1.2816E+05 0.0000E+00

Watch eleven

The relationship between the important parameters in the wide-angle imaging lens 10 of the fourth embodiment is shown in table twelve.

Figure BDA0001800362410000151

Figure BDA0001800362410000161

Watch twelve

In fig. 8A, the deviation of the imaging point of the off-axis light rays with different heights is controlled within ± 0.025 mm. In the two graphs of field curvature aberration of fig. 8B and 8C, the variation of focal length of the three representative wavelengths over the entire field of view falls within ± 0.04 mm. The distortion aberration diagram of FIG. 8D shows that the distortion aberration of the fourth embodiment is maintained within + -45%. Accordingly, the wide-angle imaging lens 10 of the fourth embodiment has good optical imaging quality under the condition that the total lens length is shortened to about 2.650 mm.

The wide-angle imaging lens 10 according to the embodiment of the present invention can achieve the following effects:

the first lens 1 is used for collecting light, and the diopter of the first lens 1 is designed to be negative so as to collect light with large angle.

The refractive index of the second lens 2 is equal to or greater than the refractive index of the other lenses with diopter (i.e. the first lens 1, the third lens 3, the fourth lens 4 and the fifth lens 5), and the abbe number of the second lens 2 is equal to or less than the refractive index of the other lenses with diopter.

The third lens 3 focuses and images the received imaging light beam, and can effectively correct spherical aberration, chromatic aberration and image field curvature by matching with the fourth lens 4 with negative diopter and the fifth lens 5 with positive diopter.

In addition, in view of the unpredictability of the optical system design, under the framework of the present invention, at least one of the following conditional expressions is satisfied to preferably improve the imaging quality of the system and to improve the drawbacks of the prior art.

In the above-described embodiment, the wide-angle imaging lens 10 satisfies the following conditions: EFL/R1 of-0.8. ltoreq.<0. Since the first lens element 1 needs a larger negative refractive power than other lens elements (i.e. the second lens element 2, the third lens element 3, the fourth lens element 4 and the fifth lens element 5) with refractive power, the first lens element 1 can reduce the outer edge E of the optically effective portion of the object-side surface 11 within this rangef1To the outer edge E of the optically ineffective portioniAnd the ratio of the thickness of (a) to the thickness of its center, and the magnitude of the angle theta can be effectively reduced. The center thickness of the first lens 1 refers to a distance from the object-side surface 11 to the image-side surface 12 of the first lens 1 on the optical axis I. The reference plane RP1 is the outer edge E of the optically effective portion passing through the image side 12f2And is tangential to the image-side surface 12, and the reference plane RP2 is the optically inactive portion P near the image-side surface 12nThe extension surface of (2). The angle θ refers to the angle of the reference plane RP1 from the reference plane RP 2.

In the above-described embodiment, the wide-angle imaging lens 10 satisfies the following conditions: the absolute value of EFL/f1 is EFL/f1, and the absolute value of EFL/f1 is more than or equal to 0.8 and less than or equal to 1.2. If the EFL/f1 is lower than the lower limit of 0.8, the problem of insufficient light-receiving capability for large-angle light is derived, and if the EFL/f1 is higher than the upper limit of 1.2, the effect of the refractive power of the first lens element 1 on the whole wide-angle imaging lens 10 becomes larger, resulting in the problem of tolerance sensitivity. If the | EFL/f1| is within the above range, the wide-angle imaging lens 10 can avoid the above problem.

In the above-described embodiment, the wide-angle imaging lens 10 satisfies the following conditions: -3.0-0 (R3+ R4)/(R3-R4) -0.8. In this range, the manufacturing tolerances of the second lens 2 are less sensitive.

In the above-described embodiment, the range of the Angle of View (Angle of View) of the wide-Angle imaging lens 10 falls within the range of 130 degrees to 150 degrees, which has an advantage of a wide Angle of View.

Based on the above, the wide-angle imaging lens of the embodiment of the invention has the following beneficial effects: by the concave-convex shape design and arrangement of the object side surface or the image side surface of the lens and the diopter combination of the lens, the wide-angle imaging lens can achieve the effect of wide visual angle, shorter lens length and good imaging quality.

Although the present invention has been described with reference to the above embodiments, it should be understood that various changes and modifications can be made therein by those skilled in the art without departing from the spirit and scope of the invention.

27页详细技术资料下载
上一篇:一种医用注射器针头装配设备
下一篇:光学成像镜头

网友询问留言

已有0条留言

还没有人留言评论。精彩留言会获得点赞!

精彩留言,会给你点赞!