TWI796350B - Optical lens - Google Patents

Abstract

An optical lens, from an object side to an image side includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens in order. The first lens to the fifth lens has a positive, a negative, a positive, a negative, and a positive refractive power in order. A sixth object-side surface of the sixth lens has a curvature radius R11, a sixth image-side surface of the sixth lens has an effective diameter r, and a substantially vertical distance between an inflection point on the sixth image-side surface and an optic axis is h. The optical lens satisfies at least one of the following conditions: 0.5

|R2/R1|, |R2/R1|

2, 2

|R11/R12|, |R11/R12|

5, 0.615

|h/r|, or|h/r|

Description

optical lens

The invention relates to an optical lens, and in particular to an optical lens with low distortion and large aperture.

With the rise of photography activities, the public's demand for camera devices has increased; and according to the nature of photography activities, camera devices must also have different characteristics. For example, when taking pictures in environments with different brightness, the light collection capability of the camera device needs to be adjusted accordingly; or when taking pictures in different media, the camera device needs to deal with the distortion caused by the different refractive indices of the media.

Generally speaking, if a new optical lens can be proposed, which has the characteristics of low distortion, large aperture, large field of view, small size and low cost, it will be able to meet most of the camera needs, and this is what people in the field are eager to achieve. one of the goals.

|h/r|及/或|h/r|

0.9。 In view of this, the present invention discloses an optical lens, which sequentially includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens from the object side to the image side. The first lens has positive diopter. The second lens has negative diopter. The third lens has positive diopter. The fourth lens has negative diopter. The fifth lens has positive diopter. The sixth lens has a diopter and includes a sixth image-side surface. The radius of the sixth image-side surface is r, the substantial vertical distance between the inflection point on the sixth image-side surface and the optical axis is h, and 0.615

|h/r| and/or |h/r|

0.9.

|R2/R1|、|R2/R1|

2、2

|R11/R12|及|R11/R12|

5。 The present invention further discloses an optical lens, which sequentially includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens from the object side to the image side. The first lens has a positive diopter and includes a first object-side surface and a first image-side surface. The curvature radius of the first object-side surface is R1, and the curvature radius of the first image-side surface is R2. The second lens has negative diopter. The third lens has positive diopter. The fourth lens has negative diopter. The fifth lens has positive diopter. The sixth lens has a diopter and includes a sixth object-side surface and a sixth image-side surface. The curvature radius of the sixth object side surface is R11, the curvature radius of the sixth image side surface is R12, and the optical lens satisfies at least one of the following conditions: 0.5

|R2/R1|, |R2/R1|

2, 2

|R11/R12| and |R11/R12|

5.

The present invention also discloses an optical lens, which sequentially includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens from the object side to the image side. The first lens has positive diopter and includes a first object-side surface and a first image-side surface. The second lens has negative diopter. The third lens has positive diopter. The fourth lens has negative diopter. The fifth lens has positive diopter. The sixth lens has a diopter and includes a sixth object-side surface and a sixth image-side surface. The optical lens satisfies at least one of the following conditions: the first object-side surface is convex, the first image-side surface is convex, the sixth object-side surface is convex, and the sixth image-side surface is concave.

In summary, the optical lens proposed by the present invention has the characteristics of low distortion, large aperture, large field of view, small size and low cost.

100‧‧‧optical lens

A‧‧‧optical axis

h‧‧‧height

IMA‧‧‧imaging surface

L1‧‧‧first lens

L2‧‧‧second lens

L3‧‧‧Third lens

L4‧‧‧Fourth lens

L5‧‧‧fifth lens

L6‧‧‧Sixth lens

f1‧‧‧first optical film

f2‧‧‧Second Optical Sheet

P‧‧‧point

r‧‧‧radius

S1‧‧‧first object side surface

S2‧‧‧First image side surface

S3‧‧‧Second object side surface

S4‧‧‧Second image side surface

S5‧‧‧Third object side surface

S6‧‧‧The third image side surface

S7‧‧‧Fourth object side surface

S8‧‧‧Fourth image side surface

S9‧‧‧fifth object side surface

S10‧‧‧fifth image side surface

S11‧‧‧Sixth object side surface

S12‧‧‧Sixth image side surface

S13, S14, S15, S16, S17‧‧‧surface

STO‧‧‧aperture

TTL‧‧‧lens total length

Fig. 1 shows a cross-sectional view of an optical lens according to an embodiment of the present invention.

FIG. 2 shows an embodiment of each lens parameter of the optical lens in FIG. 1 .

FIG. 3 lists the aspheric mathematical formula coefficients of the aspheric lens in one embodiment of the optical lens in FIG. 1 .

FIG. 4 shows an enlarged view of the sixth lens in FIG. 1 .

Several embodiments of the present invention will be disclosed in the following figures. For the sake of clarity, many practical details will be described together in the following description. It should be understood, however, that these practical details should not be used to limit the invention. That is, in some embodiments of the present invention, these practical details are unnecessary. In addition, for the sake of simplifying the drawings, some well-known structures and components will be shown in a simple and schematic manner in the drawings. And, unless otherwise indicated, the same reference numerals in different drawings can be considered as corresponding components. The illustrations in these drawings are for clearly expressing the connection relationship between the various components in these embodiments, and do not show the actual size of the various components.

Please refer to FIG. 1 , which shows a cross-sectional view of an optical lens 100 according to an embodiment of the present invention. Specifically, FIG. 1 only shows the main optical lens structure of the optical lens 100 of the present invention, and other structures, such as lens barrels and other components, can be designed by those skilled in the art, and are omitted here. The optical lens 100 has the characteristics of low distortion, large aperture, large viewing angle, small size and low cost, and can be applied to various devices with image projection or image capture functions, such as: handheld communication systems, aerial cameras, miniature cameras , sports camera lens, car camera lens, surveillance system, digital camera, digital video camera or projector, etc.

In Figure 1, define the left side of the figure as the object side, and the IMA direction of the imaging surface on the right side of the figure as the image side. The optical lens 100 includes at least six lenses in order from the object side to the image side: the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5 and the sixth lens L6, and the above Six lenses can be arranged along an optical axis A.

In this embodiment, the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, and the sixth lens L6 may have diopters, respectively. In one embodiment, among the six lenses of the optical lens 100, any three may have positive diopters, and the other three may have negative diopters; in another embodiment, each lens is arranged alternately with positive diopters and negative diopters; yet another implementation For example, the first lens L1, the third lens L3 and the fifth lens L5 may have positive diopters, the second lens L2 and the fourth lens L4 may have negative diopters, and the sixth lens L6 may have positive or negative diopters. In addition, in a specific embodiment, the sixth lens L6 has positive diopter.

TTL/F。其中，鏡頭總長可以是第一透鏡L1之第一物側表面S1與成像面之間的距離。 Furthermore, in one embodiment, the focal length of the optical lens 100 is F, and the total length of the lens is TTL, then 1.5

TTL/F. Wherein, the total length of the lens may be the distance between the first object-side surface S1 of the first lens L1 and the imaging plane.

F/Y及/或F/Y

1.5。 In one embodiment, the optical lens 100 can converge the incident light beam from the object side onto the imaging plane IMA on the image side, and if the image height of an object on the imaging plane IMA is Y, then 1

F/Y and/or F/Y

1.5.

(FNO*TTL)/(FOV*Y)及/或 (FNO*TTL)/(FOV*Y)

0.05。 In addition, in one embodiment, the field of view of the optical lens 100 is FOV, and the optical lens 100 further includes an aperture STO. The aperture value of aperture STO is FNO, then 0

(FNO*TTL)/(FOV*Y) and/or (FNO*TTL)/(FOV*Y)

0.05.

|R2/R1|及/或|R2/R1|

2。 In one embodiment, the first lens L1 includes a first object-side surface S1 and a first image-side surface S2, the radius of curvature of the first object-side surface S1 is R1, the radius of curvature of the first image-side surface S2 is R2, and 0.5

|R2/R1| and/or |R2/R1|

2.

N2、N2

N3、N4

N3、N4

N5、N6

N5、V1

V2、V3

V2、V3

V4、V5

V4及V5

V6之至少一條件。 Furthermore, in one embodiment, the first lens L1 has a refractive index N1 and an Abbe number V1, the second lens L2 has a refractive index N2 and an Abbe number V2, the third lens L3 has a refractive index N3 and an Abbe number V3, The fourth lens L4 has a refractive index N4 and an Abbe number V4, the fifth lens L5 has a refractive index N5 and an Abbe number V5, the sixth lens L6 has a refractive index N6 and an Abbe number V6, and the optical lens 100 satisfies N1

N2, N2

N3, N4

N3, N4

N5, N6

N5, V1

V2, V3

V2, V3

V4, V5

V4 and V5

At least one condition of V6.

0.05、N2-N3

0.05、N4-N3

0.05、N4-N5

0.05、N6-N5

0.05、V1-V2

5、V3-V2

5、V3-V4

5、V5-V4

5及V5-V6

5之至少一條件。 In another embodiment, the optical lens 100 satisfies N1-N2

0.05, N2-N3

0.05, N4-N3

0.05, N4-N5

0.05, N6-N5

0.05, V1-V2

5. V3-V2

5. V3-V4

5. V5-V4

5 and V5-V6

5. At least one condition.

|P5|

|P3|

|P2|

|P1|

|P4|。即，除了第四透鏡L4以外，越靠近像側的透鏡具有越高的屈光度絕對值。 In one embodiment, the first lens L1 has a diopter of P1, the second lens L2 has a diopter of P2, the third lens L3 has a diopter of P3, the fourth lens L4 has a diopter of P4, the fifth lens L5 has a diopter of P5 and the sixth lens L6 has diopter P6, and |P6|

|P5|

|P3|

|P2|

|P1|

|P4|. That is, except for the fourth lens L4, lenses closer to the image side have higher absolute values of diopter power.

In addition, in one embodiment, the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5 and the sixth lens L6 can respectively adopt a glass lens or lens made of glass material. A plastic lens made of plastic material. Among them, the material of the plastic lens may include, but not limited to, polycarbonate (polycarbonate), cycloolefin copolymer (such as APEL), and polyester resin (such as OKP4 or OKP4HT), etc., or may include the aforementioned three Mixed and/or compounded materials of at least one. Specifically, in one embodiment, the first lens L1 is a glass lens; in another embodiment, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, and the sixth lens L6 are plastic lenses or glass lens.

In addition, in one embodiment, the second lens L2, the fourth lens L4, and the sixth lens L6 can be made of the same material, or made of materials with the same refractive index and Abbe number; in another embodiment, The third lens L3 and the fifth lens L5 can be made of the same material, or can be made of materials with the same refractive index and Abbe number. In yet another embodiment, the second lens L2, the fourth lens L4, and the sixth lens L6 have the same refractive index and/or Abbe number, and/or the third lens L3 and the fifth lens L5 have the same refractive index and/or Abbe number.

Furthermore, in one embodiment, the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5 and the sixth lens L6 can be respectively a spherical lens, a free-form surface lens or a aspheric lens. In a specific embodiment, at least one of the first lens L1 , the second lens L2 , the fourth lens L4 , the seventh lens L7 and the eighth lens L8 is an aspherical lens. Specifically, in one embodiment, the first lens L1 , the second lens L2 , the third lens L3 , the fourth lens L4 , the fifth lens L5 and the sixth lens L6 are all aspherical lenses.

Specifically, each free-form lens has at least one free-form surface, meaning that the object-side surface and/or image-side surface of the free-form lens is a free-form surface; and each aspheric lens has at least one aspheric surface, meaning That is, the object-side surface and/or the image-side surface of the aspheric lens is an aspheric surface. And each aspheric surface can satisfy the following mathematical formula:

Among them, Z is the coordinate value in the direction of the optical axis OA, with the light transmission direction as the positive direction, A4, A6, A8, A10, A12, A14 and A16 are the aspheric coefficients, K is the quadric surface constant, C=1/ R, R is the radius of curvature, Y is the coordinate value perpendicular to the direction of the optical axis OA, and the direction away from the optical axis OA is the positive direction. In addition, the values of various parameters or coefficients of each aspheric surface mathematical formula can be set separately to determine the focal length of each position point on the aspheric surface.

FIG. 2 shows an embodiment of each lens parameter of the optical lens 100 in FIG. 1 , which includes the radius of curvature, thickness, refractive index, and Abbe number (dispersion coefficient) of each lens. The surface codes of the lenses are arranged sequentially from the object side to the image side, for example: "St" represents the aperture St, "S1" represents the first object-side surface S1 of the first lens L1, and "S2" represents the surface of the first lens L1 The first image-side surface S2 . . . and so on, “ S13 ” and “ S14 ” represent the surface S13 facing the object side and the surface S14 facing the image side of the first optical sheet f1 respectively. In addition, "thickness" represents the distance between the surface and a surface adjacent to the image side. For example, the "thickness" of the first object-side surface S1 is the first object-side surface S1 and the first image-side surface S2 of the first lens L1. The distance between; the "thickness" of the first image-side surface S2 is the distance between the first image-side surface S2 and the object-side surface S3 of the second lens L2.

FIG. 3 lists the aspherical coefficients of the aspheric lens in one embodiment of the optical lens 100 in FIG. 1 . If the surfaces S1-S12 of the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, and the sixth lens L6 of the optical lens 100 are respectively aspheric surfaces, then the respective aspheric surfaces The various coefficients of the spherical mathematical formula can be shown in Figure 3.

Referring to FIGS. 1 to 3 , the first object-side surface S1 of the first lens L1 may have a positive refractive power, and the first image-side surface S2 may have a negative refractive power. The first object-side surface S1 may be a convex surface protruding toward the object side, and the first image-side surface S2 may be a convex surface protruding toward the image side. Further, the first lens L1 may be a lens with positive diopter, including but not limited to any one or combination of biconvex lens with positive diopter, glass or plastic lens, and spherical or aspheric lens.

The second object-side surface S3 , the fourth object-side surface S7 , the second image-side surface S4 , and the fourth image-side surface S8 of the second lens L2 and the fourth lens L4 may all have positive refractive powers. The second object-side surface S3 and the fourth object-side surface S7 may respectively be convex surfaces protruding toward the object side, and the second image-side surface S4 and the fourth image-side surface S8 may respectively be concave surfaces concave toward the object side. Further, the second lens L2 and the fourth lens L4 can respectively adopt negative diopter lenses, including but not limited to any one or combination of negative diopter convex-concave lenses, glass or plastic lenses, and spherical or aspheric lenses.

The third object-side surface S5 , the fifth object-side surface S9 , the third image-side surface S6 , and the fifth image-side surface S10 of the third lens L3 and the fifth lens L5 may all have negative refractive powers. The third object-side surface S5 and the fifth object-side surface S9 may respectively be concave surfaces concave toward the image side, and the third image-side surface S6 and the fifth image-side surface S10 may respectively be convex surfaces protruding toward the image side. Further, the third lens L3 and the fifth lens L5 can respectively adopt lenses with positive diopters, including but not limited to any one or combination of positive diopter meniscus lenses, glass or plastic lenses, and spherical or aspheric lenses.

The sixth object-side surface S11 and the sixth image-side surface S12 of the sixth lens L6 may both have positive refractive powers at the optical axis OA, and the sixth object-side surface S11 may be a concave surface that is concave toward the image side as a whole or a concave surface toward the image side. The object side is convex, and the sixth image-side surface S12 can be a concave surface that is concave toward the object side as a whole. Further, the sixth lens L6 can be a lens with negative diopter, including but not limited to any one or combination of convex-concave or biconcave lens with negative diopter, glass or plastic lens, and spherical or aspheric lens.

|R11/R12|及/或|R11/R12|

5。 FIG. 4 shows an enlarged view of the sixth lens L6 in FIG. 1 . As shown in Fig. 2 to Fig. 4, the curvature radius of the sixth object side surface S11 of the sixth lens L6 is R11, the curvature radius of the sixth image side surface S12 is R12, and 2

|R11/R12| and/or |R11/R12|

5.

5的條件。 In another embodiment, the optical lens 100 can also satisfy |(R11-R12)/(R11+R12)|

5 conditions.

In addition to the above features, the sixth image-side surface S12 of the sixth lens L6 further protrudes toward the image side at a position away from the optical axis A. As shown in FIG. The radius of curvature of the sixth image-side surface S12 changes from a positive refractive power to a negative refractive power from the center to a direction away from the optical axis, and thus an inflection point P is formed on the sixth side surface S12. Thus, the inflection point P is the closest point on the sixth image-side surface S12 to the imaging plane IMA. In other words, the sixth image-side surface S12 is concave toward the object side at the position intersecting the optical axis A, and protrudes toward the image side at the position of the inflection point P.

The setting of the position of the inflection point P on the sixth lens L6 can further reduce the distortion value (distorsion) of the optical lens 100, and improve the resolution of the optical lens 100, that is, increase the modulation transfer function (modulation transfer function, MTF) presented optical properties.

|h/r| 及/或|h/r|

0.9。 In one embodiment, the radius of the sixth image-side surface S12 of the sixth lens L6 is r, the substantially perpendicular distance between the inflection point P and the optical axis A is h, and 0.615

|h/r| and/or |h/r|

0.9.

Further, in a specific embodiment, there is more than one inflection point P on the sixth image-side surface S12, and the inflection point P closest to the imaging plane satisfies the aforementioned conditions.

Thus, the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5 and the sixth lens L6 combine to form the optical lens 100, so that the optical lens 100 has low distortion value and high resolution characteristics.

In one embodiment, the optical lens 100 may further include an aperture St, a first optical sheet f1 and/or a second optical sheet f2, and an image capture unit (not shown) may be arranged on the imaging surface IMA, which can The incident light beam passing through the optical lens 100 undergoes photoelectric conversion. The aperture STO can control the amount of incident light and the relative angle between the incident light and the optical axis A after passing through the aperture STO, which can effectively shorten the size of the lens. The aperture SOT can be set on the object side of the first lens L1, but this is not a limitation The aperture SOT can also be set between any two lenses or between the sixth lens L6 and the imaging surface IMA; the first optical sheet f1 is an infrared filter (IR filter), and the second optical sheet f2 is a transparent protective glass. In other embodiments, the first optical sheet f1 and the second optical sheet f2 can also be integrated into an optical element to achieve substantially the same effect.

In summary, the optical lens proposed by the present invention has the characteristics of low distortion, large aperture, large field of view, small size and low cost, and the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5 and the sixth lens L6 can be independent of each other, and the optical lens 100 as a whole has the advantage of simple manufacturing process.

While the present invention has been described by way of example and the foregoing embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. On the contrary, the invention encompasses various modifications and similar arrangements (eg, as will be apparent to those skilled in the art). Accordingly, the appended claims should be accorded the broadest interpretation to cover all such modifications and similar arrangements.

100‧‧‧optical lens

A‧‧‧optical axis

IMA‧‧‧imaging surface

L1‧‧‧first lens

L2‧‧‧second lens

L3‧‧‧Third lens

L4‧‧‧Fourth lens

L5‧‧‧fifth lens

L6‧‧‧Sixth lens

f1‧‧‧first optical film

f2‧‧‧Second Optical Sheet

S1‧‧‧first object side surface

S2‧‧‧First image side surface

S3‧‧‧Second object side surface

S4‧‧‧Second image side surface

S5‧‧‧Third object side surface

S6‧‧‧The third image side surface

S7‧‧‧Fourth object side surface

S8‧‧‧Fourth image side surface

S9‧‧‧fifth object side surface

S10‧‧‧fifth image side surface

S11‧‧‧Sixth object side surface

S12‧‧‧Sixth image side surface

S13, S14, S15, S16, S17‧‧‧surface

STO‧‧‧aperture

TTL‧‧‧lens total length

Claims (10)

An optical lens has an optical axis, and includes in sequence from the object side to the image side: a first lens with positive diopter; a second lens with negative diopter; a third lens with positive diopter; a fourth lens , has a negative diopter; a fifth lens has a positive diopter; and a sixth lens has a diopter and includes a sixth image-side surface, the radius of the sixth image-side surface is r, and the sixth image-side surface has a The substantially perpendicular distance between an inflection point and the optical axis is h, and 0.615

|h/r| and/or |h/r|

0.9. An optical lens, comprising sequentially from the object side to the image side: a first lens having a positive diopter, and comprising a first object-side surface and a first image-side surface, the radius of curvature of the first object-side surface is R1 , the radius of curvature of the first image-side surface is R2; a second lens with negative diopter; a third lens with positive diopter; a fourth lens with negative diopter; a fifth lens with positive diopter; and A sixth lens having a diopter and comprising a sixth object-side surface and a sixth image-side surface, the curvature radius of the sixth object-side surface is R11, the curvature radius of the sixth image-side surface is R12, and the Optical lens meets at least one of the following conditions: 0.5

|R2/R1|, |R2/R1|

2, 2

|R11/R12| and |R11/R12|

5. The optical lens as described in claim 2, wherein the optical lens also satisfies |(R1-R2)/(R1+R2)|

5 and/or |(R11-R12)/(R11+R12)|

5. An optical lens, comprising sequentially from the object side to the image side: a first lens with positive diopter, and including a first object-side surface and a first image-side surface; a second lens with negative diopter; a first lens Three lenses with positive diopter; a fourth lens with negative diopter; a fifth lens with positive diopter; and a sixth lens with diopter and comprising a sixth object side surface and a sixth image side surface, And the optical lens satisfies at least one of the following conditions: the first object-side surface is convex, the first image-side surface is convex, the sixth object-side surface is convex, and the sixth image-side surface is concave. The optical lens of any one of items 1, 2, and 4 of the claim, wherein the first lens is a glass lens, and/or the second lens, the third lens, the fourth lens, the fifth lens, and The sixth lenses are respectively plastic lenses or glass lenses. The optical lens according to any one of items 1, 2, and 4 of the claim, wherein the optical lens satisfies at least one of the following conditions: the second lens is a convex-convex lens, the third lens is a concave-convex lens, the first lens is a concave-convex lens, The fourth lens is a concave-convex lens, the fifth lens is a concave-convex lens, and the sixth lens is a concave-convex lens. The optical lens of any one of items 1, 2, and 4 of the claim, wherein the focal length of the optical lens is F, the total length of the lens is TTL, and 1.5

TTL/F. The optical lens of any one of items 1, 2, and 4 of the claim further includes an aperture, the aperture has an aperture value of FNO, the focal length of the optical lens is F, the image height is Y, and the field of view is FOV, then 0

(FNO*TTL)/(FOV*Y) and/or (FNO*TTL)/(FOV*Y)

0.05. Such as the optical lens of any one of items 1, 2, and 4 of the claim, wherein the image height of the imaging surface of the optical lens is Y, and the focal length of the optical lens is F, then 1

F/Y and/or F/Y

1.5. As the optical lens of any one of claim items 1, 2, and 4, wherein the first lens has a refractive index N1 and an Abbe number V1, the second lens has a refractive index N2 and an Abbe number V2, and the third lens has a refractive index N1 and an Abbe number V2. The lens has a refractive index N3 and an Abbe number V3, the fourth lens has a refractive index N4 and an Abbe number V4, the fifth lens has a refractive index N5 and an Abbe number V5, and the sixth lens has a refractive index N6 and an Abbe number V5. Number V6, and the optical lens meets at least one of the following conditions: N1

N2, N2

N3, N4

N3, N4

N5, N6

N5, V1

V2, V3

V2, V3

V4, V5

V4 and V5

V6.

Images