CN112305709B

CN112305709B - Optical lens

Info

Publication number: CN112305709B
Application number: CN201910693782.4A
Authority: CN
Inventors: 江衍辰
Original assignee: Ability Enterprise Co Ltd
Current assignee: Ability Enterprise Co Ltd
Priority date: 2019-07-30
Filing date: 2019-07-30
Publication date: 2024-01-23
Anticipated expiration: 2039-07-30
Also published as: CN112305709A

Abstract

An optical lens assembly comprising, in order from an object side to an image side: a first lens with negative diopter, a second lens with positive diopter, a third lens with positive diopter, a fourth lens with positive diopter and a fifth lens with negative diopter.

Description

Optical lens

Technical Field

The present invention relates to an optical lens, and more particularly to an optical lens with small size and good imaging quality.

Background

In recent years, as the application of imaging devices has become wider, the demand for miniaturized optical lenses has also increased. Furthermore, the imaging quality requirements for optical lenses in the market are increasing. Miniaturization, high image quality, and reduced cost have been the goal of product developers to increase the competitive advantage in the market.

Therefore, it is needed to propose a new optical lens, which can achieve the purposes of miniaturization and improving the imaging quality of the optical lens while reducing the manufacturing cost.

Disclosure of Invention

The invention relates to an optical lens. On the premise of reducing the manufacturing cost, the miniaturization of the optical lens and the improvement of the imaging quality of the optical lens are realized.

The invention provides an optical lens. The optical lens sequentially comprises from an object side to an image side: a first lens with negative diopter, a second lens with positive diopter, a third lens with positive diopter, a fourth lens with positive diopter and a fifth lens with negative diopter.

The invention further provides an optical lens. The optical lens sequentially comprises from an object side to an image side: a first lens with negative diopter, a second lens with positive diopter, a third lens with positive diopter, a fourth lens and a fifth lens with negative diopter. The fourth lens has an object-side surface recessed toward the image side.

The invention further provides an optical lens. The optical lens sequentially comprises from an object side to an image side: a first lens with negative diopter, a second lens with positive diopter, a third lens with positive diopter, a fourth lens with positive diopter and a fifth lens with diopter. The fourth lens and the fifth lens have a distance therebetween.

The invention will now be described in more detail with reference to the drawings and specific examples, which are not intended to limit the invention thereto.

Drawings

Fig. 1 is an optical lens according to an embodiment of the invention.

Fig. 2 is an optical lens according to another embodiment of the invention.

Fig. 3 is an optical lens according to another embodiment of the invention.

Fig. 4A is a diagram illustrating an embodiment of lens parameters of the optical lens of fig. 1 according to the present invention.

FIG. 4B is an aspherical mathematical formula coefficient of an aspherical lens of an embodiment of the optical lens of FIG. 1 according to the present invention.

Fig. 5A is a diagram illustrating an embodiment of lens parameters of the optical lens of fig. 2 according to the present invention.

FIG. 5B is an aspherical mathematical formula coefficient of an aspherical lens of an embodiment of the optical lens of FIG. 2 according to the present invention.

Fig. 6A is a diagram illustrating an embodiment of lens parameters of the optical lens of fig. 3 according to the present invention.

FIG. 6B is an aspherical mathematical formula coefficient of an aspherical lens of an embodiment of the optical lens of FIG. 3 according to the present invention.

FIG. 7 is a diagram illustrating the performance of the optical lens of FIGS. 4A, 5A and 6A according to the present invention.

Wherein, the reference numerals:

OL1: optical lens

L1: first lens L2: second lens

L3: third lens L4: fourth lens

L5: fifth lens OA: optical axis

S1, S3, S5, S7, S9, S11: object side surface

S2, S4, S6, S8, S10, S12: image side surface

I: imaging planes H, TTL: distance of

IF: inflection point St: aperture diaphragm

Cp: protective sheet

Detailed Description

The structural and operational principles of the present invention are described in detail below with reference to the accompanying drawings:

embodiments of the present invention will be described in detail below, with reference to the accompanying drawings as examples. In addition to the detailed description, the invention may be widely practiced in other embodiments, and easy alternatives, modifications, and equivalents of any described embodiments are included within the scope of the present disclosure and subject to the following claims. In the description of the present invention, numerous specific details are provided to provide a thorough understanding of the present invention; however, the invention may be practiced without some or all of these specific details. Furthermore, well-known steps or elements have not been described in detail in order to not unnecessarily obscure the present invention. The same or similar elements in the drawings will be denoted by the same or similar symbols. It is particularly noted that the drawings are for illustrative purposes only and do not represent actual dimensions or numbers of elements unless specifically indicated.

Fig. 1 is an optical lens OL1 according to an embodiment of the present invention, fig. 2 is an optical lens OL2 according to another embodiment of the present invention, and fig. 3 is an optical lens OL3 according to yet another embodiment of the present invention. Only the structures related to the embodiments of the present invention are shown and the remaining structures are omitted in order to reveal the features of the embodiments. The optical lenses OL1, OL2, OL3 can be applied to a device having an image projection or image capturing function, including but not limited to a portable computer system, a portable communication system, a video camera, a motion camera lens, a vehicle camera lens, a monitoring system, a digital camera, a digital video camera or a projector.

Referring to fig. 1, 2 and 3, the optical lenses OL1, OL2 and OL3 may include a first lens L1, a second lens L2, a third lens L3, a fourth lens L4 and a fifth lens L5 in order from an object side (object side) to an image side (image-forming side). The first lens L1, the second lens L2, the third lens L3, the fourth lens L4 and the fifth lens L5 can be arranged along an optical axis OA.

In some embodiments, the first lens L1 may have a negative diopter; the second lens L2 may have a positive refractive power; the third lens L3 may have a positive refractive power; the fourth lens L4 may have diopter, for example, positive diopter; the fifth lens L5 may have diopter, for example, negative diopter.

In some embodiments, the distance from the object side surface S1 of the first lens L1 to the imaging plane I is TTL, the focal length (focal length) of the optical lenses OL1, OL2, OL3 is EFL, and at least one of the following conditions can be satisfied by the optical lenses OL1, OL2, OL 3: 1.5.ltoreq.TTL/EFL, 2.ltoreq.TTL/EFL, 2.5.ltoreq.TTL/EFL, 3.ltoreq.TTL/EFL, 3.5.ltoreq.TTL/EFL, and 4.ltoreq.TTL/EFL.

In some embodiments, the focal length of the second lens L2 is F2, the focal length of the third lens L3 is F3, the focal length of the fourth lens L4 is F4, and the optical lenses OL1, OL2, OL3 may satisfy at least one of the following conditions: f3 F2, F4, F3, F2, F3, F4 and F2.

In some embodiments, the combined focal length of the third lens L3, the fourth lens L4 and the fifth lens L5 is F345, and the optical lenses OL1, OL2, OL3 may satisfy at least one of the following conditions: 0.2 < F2/F345 < 0.25 < F2/F345 < 0.3 < F2/F345 < 0.35 < F2/F345 < 0.6, < F2/F345 < 0.7, and < F2/F345 < 0.8).

In some embodiments, a distance is provided between the fourth lens L4 and the fifth lens L5.

In some embodiments, a radius of curvature of the object-side surface S1 of the first lens L1 is R1, a radius of curvature of the image-side surface S2 of the first lens L1 is R2, and the optical lenses OL1, OL2, OL3 may satisfy at least one of the following conditions: 0.01-0.015-0.2R 2/R1, 0.15-0R 2/R1 and 0.2-0R 2/R1.

In some embodiments, a radius of curvature of the object-side surface S3 of the second lens L2 is R3, a radius of curvature of the image-side surface S4 of the second lens L2 is R4, and the optical lenses OL1, OL2, OL3 may satisfy at least one of the following conditions: 0< |R3/R4|, 0.005|R3/R4|, 0.01|R3/R4|, |R3/R4| < 0.025|, and|R3/R4| < 0.03.

In some embodiments, the first lens L1, the second lens L2, the third lens L3, the fourth lens L4 and the fifth lens L5 can be a spherical lens, a free-form surface lens or an aspheric lens, respectively.

Specifically, each free-form surface lens has at least one free-form surface, that is, the object-side surface and/or the image-side surface of the free-form surface lens are free-form surfaces; and each aspherical lens has at least one aspherical surface, i.e., the object-side surface and/or the image-side surface of the aspherical lens are aspherical surfaces. And each aspheric surface can satisfy the following mathematical formula:

wherein Z is a coordinate value in the direction of the optical axis OA, the light transmission direction is a positive direction, A2, A4, A6, A8, a10, and a12 are aspheric coefficients, K is a quadric constant, c=1/R, R is a radius of curvature, Y is a coordinate value in the direction orthogonal to the optical axis OA, and the direction away from the optical axis OA is a positive direction. In addition, the values of the parameters or coefficients of each aspheric surface formula can be set to determine the focal length of each location point of the aspheric surface.

In some embodiments, at least one of the first to fifth lenses L1 to L5 may be a spherical lens or an aspherical lens. In one embodiment, the first lens L1 and the second lens L2 are spherical lenses, and the third lens L3, the fourth lens L4 and the fifth lens L5 are aspheric lenses. For example, the first lens element L1 and the second lens element L2 can be spherical lenses with spherical surfaces on the object-side surfaces S1 and S3 and the image-side surfaces S2 and S4, and the third lens element L3, the fourth lens element L4 and the fifth lens element L5 can be aspheric lenses with aspheric surfaces on the object-side surfaces S5, S7, S9 and the image-side surfaces S6, S8 and S10.

Furthermore, in some embodiments, the fifth lens L5 of the optical lenses OL1, OL2, OL3 is an aspheric lens, and the image side surface S10 thereof is an aspheric surface, and the image side surface S10 of the fifth lens L5 has an inflection point IF. Wherein, the distance from the inflection point IF to the optical axis OA is h, including but not limited to the shortest distance or the vertical distance from the inflection point IF to the optical axis OA; the distance from the outer edge of the image side surface S10 of the fifth lens L5 to the optical axis OA is H, including but not limited to the shortest distance or the perpendicular distance from the radius, the outer diameter, and the optical axis OA of the fifth lens L5, and the optical lenses OL1, OL2, and OL3 may satisfy at least one of the following conditions: H/H is more than or equal to 0.3 and less than or equal to 0.4 and less than or equal to 0.62, H/H is more than or equal to 0.5 and less than or equal to H, H/H, H/H is more than or equal to 0.7, H/H is more than or equal to 0.75, and H/H is more than or equal to 0.8.

In some embodiments, the first lens L1, the second lens L2, the third lens L3, the fourth lens L4 and the fifth lens L5 can be a glass lens made of glass material or a plastic lens made of plastic material, respectively. The plastic lens material may include, but is not limited to, polycarbonate (polycarbonate), cyclic olefin copolymer (e.g., APEL), and polyester resin (e.g., OKP or OKP HT), etc., or may be a mixed and/or compounded material including at least one of the foregoing three materials.

For example, in some embodiments, at least one of the first lens L1 and the second lens L2 may be a glass lens; in other embodiments, at least one of the third lens L3, the fourth lens L4 and the fifth lens L5 may be a plastic lens. In one embodiment, the first lens L1 and the second lens L2 are all glass lenses, and the third lens L3, the fourth lens L4 and the fifth lens L5 are all plastic lenses, but are not limited to the present invention.

Referring to fig. 1, 2 and 3, in some embodiments, the object-side surface S1 of the first lens L1 may be a concave surface approaching a plane and concave toward the image side, which has a negative refractive index, or may be a convex surface approaching a plane and convex toward the object side, which has a positive refractive index; the image side surface S2 of the first lens L1 may be a concave surface concave toward the object side, which has a positive refractive index. The first lens L1 may employ a lens having negative diopter, including but not limited to any one of a biconcave lens or a convex-concave lens having negative diopter, a glass lens or a plastic lens, and a spherical lens or an aspherical lens, or a combination thereof.

The object-side surface S3 of the second lens L2 may be a convex surface protruding toward the object side, which has a positive refractive index; the image side surface S4 may be a concave surface approaching the plane and concave toward the object side, which has a positive refractive index, or may be a convex surface approaching the plane and convex toward the image side, which has a negative refractive index. The second lens L2 may employ a lens having a positive refractive power, including, but not limited to, any one lens or a combination of a convex-concave lens or a biconvex lens having a positive refractive power, a glass lens or a plastic lens, and a spherical lens or an aspherical lens.

The object-side surface S5 of the third lens L3 may be a concave surface concave toward the image side, which has a negative refractive index; the image side surface S6 may be a convex surface protruding toward the image side, which has a negative refractive index. The third lens L3 may employ a lens having a positive refractive power, including, but not limited to, a meniscus lens having a positive refractive power, a glass lens, or a plastic lens, and any one lens of a spherical lens or an aspherical lens, or a combination thereof.

The object-side surface S7 of the fourth lens L4 may be a concave surface concave toward the image side, which has a negative refractive index; the image side surface S8 may be a convex surface protruding toward the image side, which has a negative refractive index. The fourth lens L4 may employ a lens having diopter including, but not limited to, a meniscus lens having positive diopter, a glass lens or a plastic lens, and any one of a spherical lens or an aspherical lens or a combination thereof.

The object-side surface S9 of the fifth lens L5 may be a convex surface protruding toward the object side, which has a positive refractive index; the image side surface S10 may be convex toward the image side away from the optical axis OA and may be concave toward the object side near the optical axis OA, which has a positive refractive index at the optical axis OA. The fifth lens L5 may employ a lens having diopter including, but not limited to, a convex-concave lens having negative diopter, a glass lens or a plastic lens, and any one of a spherical lens or an aspherical lens or a combination thereof.

In some embodiments, the optical lenses OL1, OL2, OL3 may further include an aperture St; in other embodiments, an image capturing unit (not shown) may be disposed on the imaging plane I, which may perform photoelectric conversion on the light beams passing through the optical lenses OL1, OL2, OL3. The aperture stop St may be disposed in any gap between any two of the first lens L1 to the fifth lens L5. In one embodiment, the aperture stop St is disposed between the second lens L2 and the third lens L3, but not limited thereto.

Furthermore, the optical lenses OL1, OL2, OL3 may further include a protection sheet Cp. In some embodiments, the protective sheet Cp may be disposed between the fifth lens L5 and the imaging plane I, and a filter film (not shown) may be further formed on the protective sheet Cp.

Some embodiments of the optical lenses OL1, OL2, OL3 may further include a filter (not shown) disposed between the fifth lens L5 and the protective sheet Cp; in another embodiment, the functions of protecting the image capturing unit and filtering the infrared beam can be integrated with the protecting sheet Cp at the same time.

Fig. 4A shows an embodiment of the lens parameters of the optical lens OL1 of fig. 1 according to the present invention, which includes the radius of curvature, thickness, refractive index, abbe number (abbe number) and the like of each lens. Wherein the surface codes of the lenses are sequentially arranged from the object side to the image side, for example: "St" represents the aperture St, "S1" represents the object side surface S1 of the first lens L1, "S2" represents the image side surface S2 … of the first lens L1, and "S11" and "S12" represent the object side surface S11 and the image side surface S12 of the protection sheet Cp, respectively, and so on. In addition, the "thickness" represents the distance between the surface and a surface adjacent to the image side, for example, the "thickness" of the object-side surface S1 is the distance between the object-side surface S1 of the first lens L1 and the image-side surface S2 of the first lens L1; the "thickness" of the image side surface S2 is the distance between the image side surface S2 of the first lens element L1 and the object side surface S3 of the second lens element L2.

Fig. 4B shows the aspheric mathematical coefficients of the aspheric lens of the optical lens OL1 of fig. 1 according to an embodiment of the present invention. If the object side surfaces S5, S7, S9 and the image side surfaces S6, S8, S10 of the third lens element L3, the fourth lens element L4 and the fifth lens element L5 of the optical lens OL1 are aspheric surfaces, the coefficients of the aspheric mathematical formulas can be as shown in fig. 4B.

Fig. 5A shows an embodiment of the lens parameters of the optical lens OL2 of fig. 2, which is generally defined and intended to be the same as that of fig. 4A.

Fig. 5B shows the aspheric mathematical coefficients of the aspheric lens of the optical lens OL2 of fig. 2 according to an embodiment of the present invention. If the object side surfaces S5, S7, S9 and the image side surfaces S6, S8, S10 of the third lens element L3, the fourth lens element L4 and the fifth lens element L5 of the optical lens OL2 are aspheric surfaces, the coefficients of the aspheric mathematical formulas can be as shown in fig. 5B.

Fig. 6A shows an embodiment of the lens parameters of the optical lens OL3 of fig. 3, which is generally defined and intended to be the same as that of fig. 5A.

Fig. 6B shows the aspheric mathematical coefficients of the aspheric lens of the optical lens OL3 of fig. 3 according to an embodiment of the present invention. If the object side surfaces S5, S7, S9 and the image side surfaces S6, S8, S10 of the third lens element L3, the fourth lens element L4 and the fifth lens element L5 of the optical lens OL3 are aspheric surfaces, the coefficients of the aspheric mathematical formulas can be as shown in fig. 6B.

Fig. 7 shows specific parameter representations of the optical lenses OL1, OL2, OL3 of fig. 4A, 5A, and 6A, including the focal length EFL, aperture value Fno, distance TTL from the object side surface S1 of the first lens L1 to the imaging plane I, the focal length F1 to F5 of the first lens L1 to the fifth lens L5, the combined focal length F345 of the third lens L3, the fourth lens L4, and the fifth lens L5, the distance H from the inflection point IF of the fifth lens L5 to the optical axis OA, the distance H from the outer edge of the image side surface S10 of the fifth lens L5 to the optical axis OA, the radii of curvature R1 to R4 of the object side surfaces S1, S3 and the image side surfaces S2, S4, and the values of the relation among the above parameters.

As can be seen from the above embodiments, the optical lenses OL1, OL2, OL3 can be miniaturized and have excellent imaging quality while reducing the manufacturing cost.

Of course, the present invention is capable of other various embodiments and its several details are capable of modification and variation in light of the present invention, as will be apparent to those skilled in the art, without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. An optical lens is characterized by comprising five lenses with diopters, and the lenses are sequentially arranged from an object side to an image side:

a first lens having negative diopter;

a second lens element with positive refractive power, wherein a radius of curvature of an object-side surface of the second lens element is R3, and a radius of curvature of an image-side surface of the second lens element is R4;

a third lens having positive diopter;

a fourth lens having positive diopter; and

the distance from the outer edge of the image side surface of the fifth lens to an optical axis of the optical lens is H, the image side surface of the fifth lens is provided with an inflection point, the distance from the inflection point to the optical axis is H, and the optical lens meets the conditions that H/H is more than or equal to 0.3 and less than or equal to 0.8 and R3/R4 is more than or equal to 0.03.

2. An optical lens is characterized by comprising five lenses with diopters, and the lenses are sequentially arranged from an object side to an image side:

a first lens having negative diopter;

a third lens having positive diopter;

a fourth lens element with positive refractive power, wherein the object-side surface of the fourth lens element is concave toward the image side; and

3. The optical lens as claimed in claim 1 or 2, wherein a distance from an object-side surface of the first lens element to an imaging plane is TTL, a focal length of the optical lens element is EFL, and the optical lens element satisfies at least one of the following conditions: 1.5.ltoreq.TTL/EFL, TTL/EFL.ltoreq.4.

4. The optical lens of claim 1 or 2, wherein the second lens has a focal length F2, the third lens has a focal length F3, the fourth lens has a focal length F4, and the optical lens satisfies at least one of the following conditions: f3 F2, F4, F3, F2, F3, F4 and F2.

5. The optical lens as claimed in claim 1 or 2, wherein the focal length of the second lens is F2, the combined focal length of the third lens, the fourth lens and the fifth lens is F345, and the optical lens satisfies at least one of the following conditions: the ratio of the total amount of the components to the total amount of the components is more than or equal to 0.2 and less than or equal to |F2/F345| and the total amount of the components is more than or equal to 0.8.

6. An optical lens as claimed in claim 1 or 2, wherein the optical lens satisfies at least one of the following conditions: the first lens has an image side surface concave toward the object side, and the second lens has an object side surface convex toward the object side.

7. The optical lens as claimed in claim 1 or 2, wherein a radius of curvature of an object-side surface of the first lens is R1, a radius of curvature of an image-side surface of the first lens is R2, and the optical lens satisfies 0.01+|r2/r1+|+.0.2.