TWI683129B - Lens assembly - Google Patents

Abstract

A lens assembly includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens and a seventh lens, all of which are arranged in sequence from an object side to an image side along an optical axis. The first lens is a meniscus lens with negative refractive power and includes a convex surface facing the object side. The second lens is with negative refractive power and includes a concave surface facing the object side. The third lens is with positive refractive power and includes a convex surface facing the image side. The fourth lens is with positive refractive power. The fifth lens is with positive refractive power. The sixth lens is with negative refractive power. The seventh lens is with refractive power. The second lens and the third lens are cemented. The fifth lens and the sixth lens are cemented.

Description

Imaging lens (14)

The invention relates to an imaging lens.

The current development trend of imaging lenses, in addition to the continuous development of miniaturization, with different application requirements, also need to have the ability to have a large aperture, the conventional imaging lens can no longer meet the needs of today, and needs another new architecture Can meet the needs of miniaturization and large aperture at the same time.

In view of this, the main purpose of the present invention is to provide an imaging lens which has a short total lens length and a small aperture value, but still has good optical performance.

The imaging lens of the present invention includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens in sequence from an object side to an image side along an optical axis And a seventh lens. The first lens is a crescent lens with negative refractive power and includes a convex surface, the convex surface facing the object side. The second lens has negative refractive power and includes a concave surface that faces the object side. The third lens has positive refractive power and includes a convex surface that faces the image side. The fourth lens has positive refractive power. The fifth lens has positive refractive power. The sixth lens has negative refractive power. The seventh lens has refractive power.

The second lens and the third lens are cemented, the fifth lens and the sixth lens are cemented, the fifth lens includes a convex surface, the convex surface faces the image side, and the sixth lens package A concave surface is included, and the concave surface faces the object side.

1/Nd₁f₁+1/Nd₂f₂+1/Nd₃f₃+1/Nd₄f₄+1/Nd₅f₅+1/Nd₆f₆+1/Nd₇f₇

0.7；其中，Nd₁為第一透鏡之折射率，f₁為第一透鏡之有效焦距，Nd₂為第二透鏡之折射率，f₂為第二透鏡之有效焦距，Nd₃為第三透鏡之折射率，f₃為第三透鏡之有效焦距，Nd₄為第四透鏡之折射率，f₄為第四透鏡之有效焦距，Nd₅為第五透鏡之折射率，f₅為第五透鏡之有效焦距，Nd₆為第六透鏡之折射率，f₆為第六透鏡之有效焦距，Nd₇為第七透鏡之折射率，f₇為第七透鏡之有效焦距。 The imaging lens meets the following conditions: -0.7

1/Nd ₁ f ₁ +1/Nd ₂ f ₂ +1/Nd ₃ f ₃ +1/Nd ₄ f ₄ +1/Nd ₅ f ₅ +1/Nd ₆ f ₆ +1/Nd ₇ f ₇

0.7; where, Nd ₁ is the refractive index of the first lens, f ₁ is the effective focal length of the first lens, Nd ₂ is the refractive index of the second lens, f ₂ is the effective focal length of the second lens, and Nd ₃ is the third lens Refractive index, f ₃ is the effective focal length of the third lens, Nd ₄ is the refractive index of the fourth lens, f ₄ is the effective focal length of the fourth lens, Nd ₅ is the refractive index of the fifth lens, and f ₅ is the fifth lens For the effective focal length, Nd ₆ is the refractive index of the sixth lens, f ₆ is the effective focal length of the sixth lens, Nd ₇ is the refractive index of the seventh lens, and f ₇ is the effective focal length of the seventh lens.

TTL/θ_m

0.45；其中，TTL為第一透鏡之物側面至一成像面於光軸上之一間距，此間距之單位為mm，θ_m為成像鏡頭之一最大半視角，此最大半視角之單位為度。 The imaging lens meets the following conditions: 0.2

TTL/θ _m

0.45; where, TTL is the distance between the object side of the first lens and an imaging surface on the optical axis, the unit of this distance is mm, θ _m is one of the maximum half angle of view of the imaging lens, and the unit of this maximum half angle of view is degree .

ER₁₁/f₁

-0.4；其中，ER₁₁為第一透鏡之物側面之有效半徑，f₁為第一透鏡之有效焦距。 The imaging lens meets the following conditions: -0.8

ER ₁₁ /f ₁

-0.4; where ER ₁₁ is the effective radius of the object side of the first lens, and f ₁ is the effective focal length of the first lens.

Vd₂-Vd₃

50；其中，Vd₂為第二透鏡之阿貝係數，Vd₃為第三透鏡之阿貝係數。 The imaging lens meets the following conditions: 30

Vd ₂ -Vd ₃

50; where, Vd ₂ is the Abbe coefficient of the second lens, and Vd ₃ is the Abbe coefficient of the third lens.

Vd₅-Vd₆

40；其中，Vd₅為第五透鏡之阿貝係數，Vd₆為第六透鏡之阿貝係數。 The imaging lens meets the following conditions: 25

Vd ₅ -Vd ₆

40; where, Vd ₅ is the Abbe coefficient of the fifth lens, and Vd ₆ is the Abbe coefficient of the sixth lens.

The seventh lens is an aspheric lens with positive refractive power, and includes a convex surface, the convex surface facing the image side.

The imaging lens of the present invention may further include an aperture disposed between the third lens and the fourth lens.

The fourth lens includes a convex surface, and the convex surface faces the image side.

In order to make the above objects, features, and advantages of the present invention more comprehensible, preferred embodiments are described in detail below in conjunction with the accompanying drawings.

1, 2, 3‧‧‧ imaging lens

L11, L21, L31 ‧‧‧ first lens

L12, L22, L32 ‧‧‧ second lens

L13, L23, L33 ‧‧‧ third lens

L14, L24, L34 ‧‧‧ fourth lens

L15, L25, L35 ‧‧‧ fifth lens

L16, L26, L36 ‧‧‧ sixth lens

L17, L27, L37 ‧‧‧ seventh lens

ST1, ST2, ST3 ‧‧‧ aperture

OF1, OF2, OF3 ‧‧‧ filter

IMA1, IMA2, IMA3 ‧‧‧ imaging surface

OA1, OA2, OA3 ‧‧‧ optical axis

S11, S12, S13, S14, S15, S16, S17

S18, S19, S110, S111, S112, S113

S114, S115

S21, S22, S23, S24, S25, S26, S27

S28, S29, S210, S211, S212, S213

S214, S215

S31, S32, S33, S34, S35, S36, S37

S38, S39, S310, S311, S312, S313

S314, S315

FIG. 1 is a schematic diagram of a lens configuration according to the first embodiment of the imaging lens of the present invention.

Figure 2A is a longitudinal aberration diagram of the imaging lens of Figure 1.

Figure 2B is a field curvature diagram of the imaging lens of Figure 1.

Figure 2C is a distortion diagram of the imaging lens of Figure 1.

FIG. 3 is a schematic diagram of a lens configuration according to a second embodiment of the imaging lens of the present invention.

Figure 4A is a longitudinal aberration diagram of the imaging lens of Figure 3.

Figure 4B is a field curvature diagram of the imaging lens of Figure 3.

Figure 4C is a distortion diagram of the imaging lens of Figure 3.

FIG. 5 is a schematic diagram of a lens configuration of a third embodiment of the imaging lens according to the present invention.

Figure 6A is a longitudinal aberration diagram of the imaging lens of Figure 5.

Figure 6B is a graph of the field curvature of the imaging lens of Figure 5.

Figure 6C is a distortion diagram of the imaging lens of Figure 5.

Please refer to FIG. 1, which is a schematic diagram of a lens configuration according to the first embodiment of the imaging lens of the present invention. The imaging lens 1 includes a first lens L11, a second lens L12, a third lens L13, an aperture ST1, a fourth lens L14, a first lens in order from an object side to an image side along an optical axis OA1 Five lenses L15, one sixth lens L16, one seventh lens L17 and one Filter OF1. When imaging, the light from the object side is finally imaged on an imaging surface IMA1.

The first lens L11 is a crescent lens with negative refractive power, its object side S11 is convex, the image side S12 is concave, and both the object side S11 and the image side S12 are spherical surfaces.

The second lens L12 is a crescent-shaped lens with negative refractive power. The object side surface S13 is a concave surface, the image side surface S14 is a convex surface, and both the object side surface S13 and the image side surface S14 are spherical surfaces.

The third lens L13 is a crescent lens with positive refractive power, its object side S14 is concave, the image side S15 is convex, and both the object side S14 and the image side S15 are spherical surfaces.

The second lens L12 and the third lens L13 are cemented.

The fourth lens L14 is a biconvex lens with positive refractive power, its object side S17 is convex, the image side S18 is convex, and both the object side S17 and the image side S18 are spherical surfaces.

The fifth lens L15 is a biconvex lens with positive refractive power, its object side S19 is convex, the image side S110 is convex, and both the object side S19 and the image side S110 are spherical surfaces.

The sixth lens L16 is a biconcave lens with negative refractive power, its object side S110 is concave, the image side S111 is concave, and both the object side S110 and the image side S111 are spherical surfaces.

The fifth lens L15 and the sixth lens L16 are cemented.

The seventh lens L17 is a biconvex lens with positive refractive power, its object side S112 is convex, the image side S113 is convex, and both the object side S112 and the image side S113 are aspherical surfaces.

The object side S114 and the image side S115 of the filter OF1 are both flat.

In addition, the imaging lens 1 in the first embodiment satisfies any one of the following five conditions:

Where Nd1 ₁ is the refractive index of the first lens L11, f1 ₁ is the effective focal length of the first lens L11, Nd1 ₂ is the refractive index of the second lens L12, f1 ₂ is the effective focal length of the second lens L12, and Nd1 ₃ is the The refractive index of the three lenses L13, f1 ₃ is the effective focal length of the third lens L13, Nd1 ₄ is the refractive index of the fourth lens L14, f1 ₄ is the effective focal length of the fourth lens L14, Nd1 ₅ is the refractive index of the fifth lens L15 , F1 ₅ is the effective focal length of the fifth lens L15, Nd1 ₆ is the refractive index of the sixth lens L16, f1 ₆ is the effective focal length of the sixth lens L16, Nd1 ₇ is the refractive index of the seventh lens L17, and f1 ₇ is the seventh The effective focal length of the lens L17, TTL1 is the distance between the object side S11 of the first lens L11 and the imaging plane IMA1 on the optical axis OA1, the unit of this distance is mm, θ1 _m is the maximum half angle of view of the imaging lens 1, the maximum half angle of view The unit is degree, ER1 ₁₁ is the effective radius of the object side S11 of the first lens L11, Vd1 ₂ is the Abbe coefficient of the second lens L12, Vd1 ₃ is the Abbe coefficient of the third lens L13, and Vd1 ₅ is the fifth lens the Abbe L15, Vd1 ₆ is the Abbe number of the sixth lens L16.

With the above lens, aperture and the design satisfying the conditions (1) to (5), the imaging lens 1 can effectively shorten the total lens length, reduce the aperture value, and effectively correct aberrations.

Table 1 is a table of related parameters of each lens of the imaging lens 1 in FIG. 1. The data in Table 1 shows that the effective focal length of the imaging lens 1 of the first embodiment is equal to 3.78 mm, the aperture value is equal to 1.63, and the total lens length is equal to 18.93 mm.

The aspherical surface concave degree z of each lens in Table 1 is obtained by the following formula: z=ch ² /{1+[1-(k+1)c ² h ² ] ^1/2 }+Ah ⁴ +Bh ⁶ + Ch ⁸ +Dh ¹⁰

Among them: c: curvature; h: vertical distance from any point on the lens surface to the optical axis; k: conic coefficient; A~D: aspherical coefficient.

Table 2 is the related parameter table of the aspherical surface of each lens in Table 1, where k is the conic constant and A~D are the aspherical coefficients.

In the imaging lens 1 of the first embodiment, the refractive index Nd1 ₁ =1.52 of the first lens L11, the effective focal length f1 ₁ =-6.29 mm of the first lens L11, the refractive index Nd1 ₂ =1.51 of the second lens L12, the second The effective focal length of the lens L12 f1 ₂ =-9.148mm, the refractive index of the third lens L13 Nd1 ₃ = 1.88, the effective focal length of the third lens L13 f1 ₃ =9.425mm, the refractive index of the fourth lens L14 Nd1 ₄ =1.52, the first The effective focal length f4 _{4 of the} four lens L14 = 8.382 mm, the refractive index Nd1 ₅ = 1.76 of the fifth lens L15, the effective focal length f1 ₅ = 7.223 mm of the fifth lens L15, the refractive index Nd1 ₆ = 1.91 of the sixth lens L16, the first The effective focal length of the six lens L16 f1 ₆ =-5.995 mm, the refractive index of the seventh lens L17 Nd1 ₇ =1.65, the effective focal length of the seventh lens L17 f1 ₇ =9.447 mm, the object side S11 of the first lens L11 to the imaging plane IMA1 The distance between the optical axis OA1 and TTL1=18.93mm, the maximum half angle of view θ1 _m =50.1 degrees, the effective radius ER1 ₁₁ of the object side S11 of the first lens L11 ₁₁ =4.185mm, and the Abbe coefficient Vd1 _{2 of the} second lens L12=63 , The Abbe coefficient Vd1 _{3 of the} third lens L13 = 30, the Abbe coefficient Vd1 _{5 of the} fifth lens L15 = 51, and the Abbe coefficient Vd1 _{6 of the} sixth lens L16 = 20. From the above data, 1/Nd1 ₁ f1 can be obtained ₁ +1/Nd1 ₂ f1 ₂ +1/Nd1 ₃ f1 ₃ +1/Nd1 ₄ f1 ₄ +1/Nd1 ₅ f1 ₅ +1/Nd1 ₆ f1 ₆ +1/Nd1 ₇ f1 ₇ =0.0135, TTL1/θ1 _m =0.38, ER1 ₁₁ /f1 ₁ =-0.67, Vd1 ₂ -Vd13=33, Vd1 ₅ -Vd1 ₆ =31, all can meet the requirements of the above conditions (1) to (5).

In addition, the optical performance of the imaging lens 1 of the first embodiment can also meet the requirements, which can be seen from FIGS. 2A to 2C. Shown in FIG. 2A is a longitudinal aberration (Longitudinal Aberration) diagram of the imaging lens 1 of the first embodiment. Shown in FIG. 2B is a field curvature diagram of the imaging lens 1 of the first embodiment. Shown in FIG. 2C is a distortion diagram of the imaging lens 1 of the first embodiment.

It can be seen from FIG. 2A that the imaging lens 1 of the first embodiment has a longitudinal aberration value between -0.05 mm and 0.05 mm for light rays with wavelengths of 0.470 μm, 0.510 μm, 0.555 μm, 0.610 μm, and 0.650 μm. between.

As can be seen from FIG. 2B, the imaging lens 1 of the first embodiment has a wavelength of 0.470 μm, 0.510 μm, 0.555 μm, 0.610 μm, and 0.650 μm in the meridional (Tangential) direction and sagittal (Sagittal) direction. The curvature of field is between -0.04mm and 0.04mm.

It can be seen from Figure 2C (the five lines in the figure almost overlap, so that there seems to be only one line), the imaging lens 1 of the first embodiment has a pair of wavelengths of 0.470 μm, 0.510 μm, 0.555 μm, 0.610 μm, 0.650 The distortion caused by the light of μm is between -33% and 0%.

It is obvious that the longitudinal aberration, field curvature, and distortion of the imaging lens 1 of the first embodiment can be effectively corrected, thereby obtaining better optical performance.

Please refer to FIG. 3, which is a schematic diagram of a lens configuration according to a second embodiment of the imaging lens of the present invention. The imaging lens 2 includes a first lens L21, a second lens L22, a third lens L23, an aperture ST2, a fourth lens L24, a first lens in order from an object side to an image side along an optical axis OA2 Five lenses L25, a sixth lens L26, a seventh lens L27 and a filter OF2. When imaging, the light from the object side is finally imaged on an imaging surface IMA2.

The first lens L21 is a crescent lens with negative refractive power, its object side S21 is convex, the image side S22 is concave, and both the object side S21 and the image side S22 are spherical surfaces.

The second lens L22 is a crescent-shaped lens with negative refractive power, its object side S23 is concave, the image side S24 is convex, and both the object side S23 and the image side S24 are spherical surfaces.

The third lens L23 is a crescent lens with positive refractive power. The object side S24 is concave, the image side S25 is convex, and the object side S24 and the image side S25 are both spherical surfaces.

The second lens L22 and the third lens L23 are cemented.

The fourth lens L24 is a biconvex lens with positive refractive power, its object side S27 is convex, the image side S28 is convex, and both the object side S27 and the image side S28 are spherical surfaces.

The fifth lens L25 is a biconvex lens with positive refractive power, its object side S29 is convex, the image side S210 is convex, and both the object side S29 and the image side S210 are spherical surfaces.

The sixth lens L26 is a biconcave lens with negative refractive power, its object side S210 is concave, the image side S211 is concave, and both the object side S210 and the image side S211 are spherical surfaces.

The fifth lens L25 and the sixth lens L26 are cemented.

The seventh lens L27 is a biconvex lens with positive refractive power, and its object side S212 is The convex surface, the image side surface S213 is a convex surface, and the object side surface S212 and the image side surface S213 are both aspherical surfaces.

The object side S214 and the image side S215 of the filter OF2 are both flat.

In addition, the imaging lens 2 in the second embodiment satisfies any one of the following five conditions:

Where Nd2 ₁ is the refractive index of the first lens L21, f2 ₁ is the effective focal length of the first lens L21, Nd2 ₂ is the refractive index of the second lens L22, f2 ₂ is the effective focal length of the second lens L22, and Nd2 ₃ is the The refractive index of the three lenses L23, f2 ₃ is the effective focal length of the third lens L23, Nd2 ₄ is the refractive index of the fourth lens L24, f2 ₄ is the effective focal length of the fourth lens L24, Nd2 ₅ is the refractive index of the fifth lens L25 , F2 ₅ is the effective focal length of the fifth lens L25, Nd2 ₆ is the refractive index of the sixth lens L26, f2 ₆ is the effective focal length of the sixth lens L26, Nd2 ₇ is the refractive index of the seventh lens L27, and f2 ₇ is the seventh The effective focal length of the lens L27, TTL2 is the distance between the object side S21 of the first lens L21 and the imaging plane IMA2 on the optical axis OA2, the unit of this distance is mm, θ2 _m is the maximum half angle of view of the imaging lens 2, the maximum half angle of view The unit is degree, ER2 ₁₁ is the effective radius of the object side S21 of the first lens L21, Vd2 ₂ is the Abbe coefficient of the second lens L22, Vd2 ₃ is the Abbe coefficient of the third lens L23, Vd2 ₅ is the fifth lens the Abbe L25, Vd2 ₆ is the Abbe number of the sixth lens L26.

With the above lens, aperture and the design satisfying the conditions (6) to (10), the imaging lens 2 can effectively shorten the total lens length, reduce the aperture value, and effectively correct aberrations.

Table 3 is a table of related parameters of each lens of the imaging lens 2 in FIG. 3. The data in Table 3 shows that the effective focal length of the imaging lens 2 of the second embodiment is 3.78 mm, the aperture value is 1.62, and the total lens length is 18.97 mm.

The aspherical surface depression degree z of each lens in Table 3 is obtained by the following formula: z=ch ² /{1+[1-(k+1)c ² h ² ] ^1/2 }+Ah ⁴ +Bh ⁶ + Ch ⁸ +Dh ¹⁰

Among them: c: curvature; h: vertical distance from any point on the lens surface to the optical axis; k: conic coefficient; A~D: aspherical coefficient.

Table 4 is the related parameter table of the aspherical surface of each lens in Table 3, where k is the conic constant and A~D are the aspherical coefficients.

In the imaging lens 2 of the second embodiment, the refractive index Nd2 ₁ =1.52 of the first lens L21, the effective focal length f2 ₁ =-6.31 mm of the first lens L21, the refractive index Nd2 ₂ =1.51 of the second lens L22, the second The effective focal length of the lens L22 f2 ₂ =-9.492mm, the refractive index of the third lens L23 Nd2 ₃ = 1.89, the effective focal length of the third lens L23 f2 ₃ =9.716mm, the refractive index of the fourth lens L24 Nd2 ₄ = 1.49, The effective focal length of the four lens L24 f2 ₄ =8.918 mm, the refractive index of the fifth lens L25 Nd2 ₅ =1.78, the effective focal length of the fifth lens L25 f2 ₅ =8.106 mm, the refractive index of the sixth lens L26 Nd2 ₆ =1.93, The effective focal length of the six lens L26 f2 ₆ =-6.841 mm, the refractive index of the seventh lens L27 Nd2 ₇ =1.68, the effective focal length of the seventh lens L27 f2 ₇ =8.946 mm, the object side S21 of the first lens L21 to the imaging plane IMA2 The distance between the optical axis OA2 and TTL2=18.97mm, the maximum half angle of view θ2 _m =50.1 degrees, the effective radius ER2 ₁₁ of the object side S21 of the first lens L21 ₁₁ =4.186mm, and the Abbe coefficient Vd2 _{2 of the} second lens L22=64.2 , The Abbe coefficient Vd2 _{3 of the} third lens L23 = 30, the Abbe coefficient Vd2 _{5 of the} fifth lens L25 = 50, and the Abbe coefficient Vd2 _{6 of the} sixth lens L26 = 18, 1/Nd2 ₁ f2 can be obtained from the above data ₁ +1/Nd2 ₂ f2 ₂ +1/Nd2 ₃ f2 ₃ +1/Nd2 ₄ f2 ₄ +1/Nd2 ₅ f2 ₅ +1/Nd2 ₆ f2 ₆ +1/Nd2 ₇ f2 ₇ =0.0159, TTL2/θ2 _m =0.38, ER2 ₁₁ /f2 ₁ =-0.66, Vd2 ₂ -Vd2 ₃ =34.2, Vd2 _5- Vd2 ₆ =32, all can meet the requirements of the above conditions (6) to (10).

In addition, the optical performance of the imaging lens 2 of the second embodiment can also meet the requirements, which can be seen from FIGS. 4A to 4C. FIG. 4A is a longitudinal aberration (Longitudinal Aberration) diagram of the imaging lens 2 of the second embodiment. Shown in FIG. 4B is a field curvature diagram of the imaging lens 2 of the second embodiment. Shown in FIG. 4C is a distortion diagram of the imaging lens 2 of the second embodiment.

As can be seen from FIG. 4A, the imaging lens 2 of the second embodiment has a longitudinal aberration value between -0.05 mm and 0.05 mm for light rays with wavelengths of 0.470 μm, 0.510 μm, 0.555 μm, 0.610 μm, and 0.650 μm. between.

As can be seen from FIG. 4B, the imaging lens 2 of the second embodiment has a wavelength of For 0.470μm, 0.510μm, 0.555μm, 0.610μm, 0.650μm light, the field curvature in the meridional (Tangential) direction and sagittal (Sagittal) direction is between -0.04mm and 0.04mm.

It can be seen from Figure 4C (the five lines in the figure almost coincide so that there is only one line), the imaging lens 2 of the second embodiment has a pair of wavelengths of 0.470 μm, 0.510 μm, 0.555 μm, 0.610 μm, 0.650 The distortion caused by the light of μm is between -33% and 0%.

It is obvious that the longitudinal aberration, field curvature, and distortion of the imaging lens 2 of the second embodiment can be effectively corrected, thereby obtaining better optical performance.

Please refer to FIG. 5, which is a schematic diagram of a lens configuration according to a third embodiment of the imaging lens of the present invention. The imaging lens 3 includes a first lens L31, a second lens L32, a third lens L33, an aperture ST3, a fourth lens L34, a first lens in order from an object side to an image side along an optical axis OA3 Five lenses L35, a sixth lens L36, a seventh lens L37 and a filter OF3. When imaging, the light from the object side is finally imaged on an imaging surface IMA3.

The first lens L31 is a crescent lens with negative refractive power, its object side S31 is convex, the image side S32 is concave, and both the object side S31 and the image side S32 are spherical surfaces.

The second lens L32 is a crescent lens with negative refractive power, its object side S33 is concave, the image side S34 is convex, and both the object side S33 and the image side S34 are spherical surfaces.

The third lens L33 is a crescent lens with positive refractive power, its object side S34 is concave, the image side S35 is convex, and both the object side S34 and the image side S35 are spherical surfaces.

The second lens L32 and the third lens L33 are cemented.

The fourth lens L34 is a biconvex lens with positive refractive power, its object side S37 is convex, the image side S38 is convex, and both the object side S37 and the image side S38 are spherical surfaces.

The fifth lens L35 is a biconvex lens with positive refractive power, and its object side S39 is The convex surface, the image side surface S310 is a convex surface, and the object side surface S39 and the image side surface S310 are spherical surfaces.

The sixth lens L36 is a biconcave lens with negative refractive power. The object side surface S310 is a concave surface, the image side surface S311 is a concave surface, and both the object side surface S310 and the image side surface S311 are spherical surfaces.

The fifth lens L35 and the sixth lens L36 are cemented.

The seventh lens L37 is a biconvex lens with positive refractive power, its object side S312 is convex, the image side S313 is convex, and both the object side S312 and the image side S313 are aspherical surfaces.

The object side S314 and the image side S315 of the filter OF3 are both flat.

In addition, the imaging lens 3 in the third embodiment satisfies any one of the following five conditions:

Where Nd3 ₁ is the refractive index of the first lens L31, f3 ₁ is the effective focal length of the first lens L31, Nd3 ₂ is the refractive index of the second lens L32, f3 ₂ is the effective focal length of the second lens L32, and Nd3 ₃ is the first The refractive index of the three lens L33, f3 ₃ is the effective focal length of the third lens L33, Nd3 ₄ is the refractive index of the fourth lens L34, f3 ₄ is the effective focal length of the fourth lens L34, Nd3 ₅ is the refractive index of the fifth lens L35 , F3 ₅ is the effective focal length of the fifth lens L35, Nd3 ₆ is the refractive index of the sixth lens L36, f3 ₆ is the effective focal length of the sixth lens L36, Nd3 ₇ is the refractive index of the seventh lens L37, and f3 ₇ is the seventh The effective focal length of the lens L37, TTL3 is the distance between the object side S31 of the first lens L31 and the imaging plane IMA3 on the optical axis OA3, the unit of this distance is mm, θ3 _m is the maximum half angle of view of the imaging lens 3, the maximum half angle of view The unit is degree, ER3 ₁₁ is the effective radius of the object side S31 of the first lens L31, Vd3 ₂ is the Abbe coefficient of the second lens L32, Vd3 ₃ is the Abbe coefficient of the third lens L33, and Vd3 ₅ is the fifth lens the Abbe L35, Vd3 ₆ is the Abbe number of the sixth lens L36.

With the above lens, aperture and the design satisfying condition (11) to condition (15), the imaging lens 3 can effectively shorten the total lens length, reduce the aperture value, and effectively correct aberrations.

Table 5 is a table of related parameters of each lens of the imaging lens 3 in FIG. 5. The data in Table 5 shows that the effective focal length of the imaging lens 3 of the third embodiment is 3.78 mm, the aperture value is 1.62, and the total lens length is 18.96 mm.

The aspherical surface depression degree z of each lens in Table 5 is obtained by the following formula: z=ch ² /{1+[1-(k+1)c ² h ² ] ^1/2 }+Ah ⁴ +Bh ⁶ + Ch ⁸ +Dh ¹⁰

Among them: c: curvature; h: vertical distance from any point on the lens surface to the optical axis; k: conic coefficient; A~D: aspherical coefficient.

Table 6 is a table of related parameters of the aspherical surfaces of the lenses in Table 5, where k is the conic constant and A~D are the aspherical coefficients.

In the imaging lens 3 of the third embodiment, the refractive index Nd3 ₁ =1.5 of the first lens L31, the effective focal length f3 ₁ =-6.38 mm of the first lens L31, the refractive index Nd3 ₂ =1.52 of the second lens L32, the second The effective focal length of lens L32 f3 ₂ =-9.193mm, the refractive index of third lens L33 Nd3 ₃ =1.9, the effective focal length of third lens L33 f3 ₃ =9.558mm, the refractive index of fourth lens L34 Nd3 ₄ =1.5, The effective focal length of the four lens L34 f3 ₄ = 8.745 mm, the refractive index of the fifth lens L35 Nd3 ₅ = 1.78, the effective focal length of the fifth lens L35 f3 ₅ = 7.826 mm, the refractive index of the sixth lens L36 Nd3 ₆ = 1.95, The effective focal length of the six lens L36 f3 ₆ =-6.441 mm, the refractive index of the seventh lens L37 Nd3 ₇ =1.68, the effective focal length of the seventh lens L37 f3 ₇ =8.877 mm, the object side S31 of the first lens L31 to the imaging plane IMA3 The distance between the optical axis OA3 is TTL3=18.96mm, the maximum half angle of view θ3 _m =50.1 degrees, the effective radius ER3 ₁₁ of the object side S31 of the first lens L31 ₁₁ =4.187mm, and the Abbe coefficient Vd3 _{2 of the} second lens L32 ₂ =64 , Abbe coefficient Vd3 ₃ =32 of the third lens L33, Abbe coefficient Vd3 ₅ =50 of the fifth lens L35, Abbe coefficient Vd3 ₆ =19 of the sixth lens L36, 1/Nd3 ₁ f3 can be obtained from the above data ₁ +1/Nd3 ₂ f3 ₂ +1/Nd3 ₃ f3 ₃ +1/Nd3 ₄ f3 ₄ +1/Nd3 ₅ f3 ₅ +1/Nd3 ₆ f3 ₆ +1/Nd3 ₇ f3 ₇ =0.0146, TTL3/θ3 _m =0.38, ER3 ₁₁ /f3 ₁ =-0.66, Vd3 ₂ -Vd3 ₃ =32, Vd3 ₅ -Vd3 ₆ =31, all can meet the requirements of the above conditions (11) to (15).

In addition, the optical performance of the imaging lens 3 of the third embodiment can also achieve This can be seen from Figures 6A to 6C. FIG. 6A shows a longitudinal aberration (Longitudinal Aberration) diagram of the imaging lens 3 of the third embodiment. FIG. 6B shows a field curvature diagram of the imaging lens 3 of the third embodiment. Shown in FIG. 6C is a distortion diagram of the imaging lens 3 of the third embodiment.

As can be seen from FIG. 6A, the imaging lens 3 of the third embodiment has a longitudinal aberration value between -0.05mm and 0.05mm for light with wavelengths of 0.470μm, 0.510μm, 0.555μm, 0.610μm, 0.650μm between.

As can be seen from FIG. 6B, the imaging lens 3 of the third embodiment has a wavelength of 0.470 μm, 0.510 μm, 0.555 μm, 0.610 μm, and 0.650 μm in the meridional (Tangential) direction and sagittal (Sagittal) direction. The curvature of field is between -0.04mm and 0.04mm.

It can be seen from Figure 6C (the five lines in the figure almost overlap so that there is only one line), the imaging lens 3 of the third embodiment has a pair of wavelengths of 0.470 μm, 0.510 μm, 0.555 μm, 0.610 μm, 0.650 The distortion caused by the light of μm is between -33% and 0%.

It is obvious that the longitudinal aberration, field curvature, and distortion of the imaging lens 3 of the third embodiment can be effectively corrected, thereby obtaining better optical performance.

1‧‧‧Imaging lens

L11‧‧‧First lens

L12‧‧‧Second lens

L13‧‧‧third lens

L14‧‧‧Fourth lens

L15‧‧‧fifth lens

L16‧‧‧Sixth lens

L17‧‧‧Seventh lens

ST1‧‧‧Aperture

OF1‧‧‧filter

OA1‧‧‧Optical axis

IMA1‧‧‧Imaging surface

S11, S12, S13, S14, S15

S16, S17, S18, S19, S110

S111, S112, S113, S114, S115

Claims (10)

An imaging lens, along an optical axis, from an object side to an image side in sequence includes: a first lens, the first lens is a crescent-shaped lens with negative refractive power and includes a convex surface, the convex surface facing the object side; A second lens with negative refractive power and including a concave surface facing the object side; a third lens with positive refractive power and including a convex surface facing the image side; a first Four lenses, the fourth lens has positive refractive power; a fifth lens, the fifth lens has positive refractive power; a sixth lens, the sixth lens has negative refractive power and is a biconcave lens; and a seventh lens, the seventh The lens has refractive power. An imaging lens, along an optical axis, from an object side to an image side in sequence includes: a first lens, the first lens is a crescent-shaped lens with negative refractive power and includes a convex surface, the convex surface facing the object side; A second lens with negative refractive power and including a concave surface facing the object side; a third lens with positive refractive power and including a convex surface facing the image side; a first Four lenses, the fourth lens has positive refractive power; a fifth lens, the fifth lens has positive refractive power; a sixth lens, the sixth lens has negative refractive power; and A seventh lens, the seventh lens has refractive power; wherein the second lens and the third lens are cemented. An imaging lens, along an optical axis, from an object side to an image side in sequence includes: a first lens, the first lens is a crescent-shaped lens with negative refractive power and includes a convex surface, the convex surface facing the object side; A second lens with negative refractive power and including a concave surface facing the object side; a third lens with positive refractive power and including a convex surface facing the image side; a first Four lenses, the fourth lens has a positive refractive power; a fifth lens, the fifth lens has a positive refractive power; a sixth lens, the sixth lens has a negative refractive power; and a seventh lens, the seventh lens has a refractive power; The imaging lens meets the following conditions: -0.7

1/Nd ₁ f ₁ +1/Nd ₂ f ₂ +1/Nd ₃ f ₃ +1/Nd ₄ f ₄ +1/Nd ₅ f ₅ +1/Nd ₆ f ₆ +1/Nd ₇ f ₇

0.7 where Nd _{1 is} the refractive index of the first lens, f _{1 is} the effective focal length of the first lens, Nd _{2 is} the refractive index of the second lens, f _{2 is} the effective focal length of the second lens, and Nd ₃ is The refractive index of the third lens, f _{3 is} the effective focal length of the third lens, Nd _{4 is} the refractive index of the fourth lens, f _{4 is} the effective focal length of the fourth lens, Nd _{5 is} the refraction of the fifth lens Ratio, f _{5 is} the effective focal length of the fifth lens, Nd _{6 is} the refractive index of the sixth lens, f _{6 is} the effective focal length of the sixth lens, Nd _{7 is} the refractive index of the seventh lens, and f _{7 is} the The effective focal length of the seventh lens. An imaging lens, along an optical axis, from an object side to an image side in sequence includes: a first lens, the first lens is a crescent-shaped lens with negative refractive power and includes a convex surface, the convex surface facing the object side; A second lens with negative refractive power and including a concave surface facing the object side; a third lens with positive refractive power and including a convex surface facing the image side; a first Four lenses, the fourth lens has a positive refractive power; a fifth lens, the fifth lens has a positive refractive power; a sixth lens, the sixth lens has a negative refractive power; and a seventh lens, the seventh lens has a refractive power; The imaging lens meets the following conditions: -0.8

ER ₁₁ /f ₁

-0.4 where ER ₁₁ is the effective radius of the object side of the first lens, and f _{1 is} the effective focal length of the first lens. An imaging lens, along an optical axis, from an object side to an image side in sequence includes: a first lens, the first lens is a crescent-shaped lens with negative refractive power and includes a convex surface, the convex surface facing the object side; A second lens with negative refractive power and including a concave surface facing the object side; a third lens with positive refractive power and including a convex surface facing the image side; a first Four lenses, the fourth lens has positive refractive power; a fifth lens, the fifth lens has positive refractive power; a sixth lens, the sixth lens has negative refractive power; and a seventh lens, the seventh lens has refractive power; The imaging lens meets the following conditions: 30

Vd ₂ -Vd ₃

50, where Vd _{2 is} the Abbe coefficient of the second lens, and Vd _{3 is} the Abbe coefficient of the third lens. An imaging lens, along an optical axis, from an object side to an image side in sequence includes: a first lens, the first lens is a crescent-shaped lens with negative refractive power and includes a convex surface, the convex surface facing the object side; A second lens with negative refractive power and including a concave surface facing the object side; a third lens with positive refractive power and including a convex surface facing the image side; a first Four lenses, the fourth lens has a positive refractive power; a fifth lens, the fifth lens has a positive refractive power; a sixth lens, the sixth lens has a negative refractive power; and a seventh lens, the seventh lens has a refractive power; The seventh lens is an aspheric lens. An imaging lens, along an optical axis, from an object side to an image side in sequence includes: a first lens, the first lens is a crescent-shaped lens with negative refractive power and includes a convex surface, the convex surface facing the object side; A second lens having negative refractive power and including a concave surface facing the object side; a third lens having positive refractive power and including a convex surface facing the image side; an aperture A fourth lens with positive refractive power; a fifth lens with positive refractive power; a sixth lens with negative refractive power; and a seventh lens with the seventh lens With refractive power. The imaging lens as described in any of items 1 to 7 of the patent application scope, wherein the imaging lens satisfies the following conditions: 0.2

TTL/θ _m

0.45 where TTL is the distance between the object side of the first lens and an imaging surface on the optical axis, the unit of the distance is mm, and θ _{m is} the maximum half angle of view of the imaging lens, and the unit of the maximum half angle of view For degrees. The imaging lens as described in any one of items 1 to 7 of the patent application scope, wherein the imaging lens satisfies the following conditions: 25

Vd ₅ -Vd ₆

40, where Vd _{5 is} the Abbe coefficient of the fifth lens, and Vd _{6 is} the Abbe coefficient of the sixth lens. The imaging lens as described in any one of claims 1 to 7, wherein the fourth lens includes a convex surface facing the image side, the fifth lens and the sixth lens are cemented, and the fifth lens It includes a convex surface facing the image side, and the sixth lens includes a concave surface With the surface facing the object side, the seventh lens has positive refractive power and includes a convex surface facing the image side.

Images