OPTICAL SYSTEM, LENS MODULE, AND ELECTRONIC DEVICE

TECHNICAL FIELD

The present disclosure relates to the field of optical imaging technology, and particularly to an optical system, a lens module, and an electronic device.

BACKGROUND

Currently, with the rapid development of technology, consumers have increasingly higher requirements for imaging quality of mobile electronic products. In order to meet requirements of higher-order imaging system and realize a wide-angle shooting, various types of portable electronic device capable of shooting adopt a seven-element lens. However, the existing seven-element lens cannot meet requirements of both large field angle and miniaturization.

SUMMARY

An optical system, a lens module, and an electronic device are provide to solve the above technical problems.

An optical system is provided according to implementations of the present disclosure. The optical system includes a first lens having a positive refractive power, a second lens having a refractive power, a third lens having a refractive power, a fourth lens having a refractive power, a fifth lens having a refractive power, a sixth lens having a positive refractive power, a seventh lens having a negative refractive power which are sequentially arranged from an object side to an image side along an optical axis of the optical system. The first lens has an object-side surface which is convex near the optical axis. The seventh lens has an image-side surface which is concave near the optical axis. The optical system satisfies the following expression: 4≤(Y72*TL)/(ET7*f)≤10. Y72 represents a maximum optical effective radius of the image-side surface of the seventh lens. TL represents a distance along the optical axis from the object-side surface of the first lens to an imaging plane of the optical system. ET7 represents a distance along the optical axis from an object-side surface of the seventh lens at a maximum optical effective radius to the image-side surface of the seventh lens at the maximum optical effective radius. f represents a focal length of the optical system. In the disclosure, a surface shape and the refractive power of each lens of the first to seventh lenses are rationally set, such that the seven-element optical system can meet the requirements of high pixels and good imaging quality.

When the optical system satisfies the above expressions, a balance between large field angle and thickness of the optical system can be realized, ensuring the yield of the seventh lens as well as reducing the size of the optical system.

In an implementation, the optical system satisfies the following expression: 2≤TL/EPD≤3. EPD represents an entrance pupil diameter of the optical system. When the optical system satisfies the above expression, the total length of the optical system can be reduced and the amount of incident light can be increased.

In an implementation, the optical system satisfies the following expression: 0≤MVd/f≤20. MVd represents an average of Abbe numbers of the first to seventh lenses. When the optical system satisfies the above expression, chromatic aberration can be balanced, a match between different Abbe numbers and different refractive indexes is realized, and large field angle and good optical imaging performance can be achieved through combining different materials.

In an implementation, the optical system satisfies the following expression: 0≤ET1/(CT1*f)≤1 mm⁻¹. ET1 represents a distance along the optical axis from the object-side surface of the first lens at a maximum optical effective radius to an image-side surface of the first lens at a maximum optical effective radius. CT1 represents a thickness of the first lens along the optical axis. When the optical system satisfies the above expression, it is beneficial to molding the first lens.

In an implementation, the optical system satisfies the following expression 0≤ET7/(CT7*f)≤1 mm⁻¹. CT7 represents a thickness of the seventh lens along the optical axis. When the optical system satisfies the above expression, it is beneficial to molding the seventh lens.

In an implementation, the optical system satisfies the following expression: 0≤EPD/f≤1. EPD represents an entrance pupil diameter of the optical system. When the optical system satisfies the above expression, a balance between the amount of incident light and a rearward movement of the imaging plane can be achieved, and a large aperture and a large field angle can be realized.

In an implementation, the optical system satisfies the following expression: 0≤(MIN6*MAX7)/(MAX6*MIN7)≤1. MIN6 represents a minimum thickness of the sixth lens along the optical axis within a maximum optical effective radius. MAX6 represents a maximum thickness of the sixth lens along the optical axis within the maximum optical effective radius. MIN7 represents a minimum thickness of the seventh lens along the optical axis within a maximum optical effective radius. MAX7 represents a maximum thickness of the seventh lens along the optical axis within the maximum optical effective radius. When the optical system satisfies the above expression, a yield of injection molding can be improved, and a balance between a large field angle and astigmatism can be realized.

In an implementation, the optical system satisfies the following expression: 0≤(CT5+CT7)/CT6≤2. CT5 represents a thickness of the fifth lens along the optical axis. CT6 represents a thickness of the sixth lens along the optical axis. CT7 represents a thickness of the seventh lens along the optical axis. When the optical system satisfies the above expression, it is beneficial to enlarging the field angle and balancing aberrations.

In an implementation, the optical system satisfies the following expression: 1≤TL/ImgH≤2. ImgH represents half of an image height corresponding to a maximum field angle of the optical system. When the optical system satisfies the above expression, it is beneficial to realizing the miniaturization of the optical system.

In an implementation, a lens module is provided according to implementations of the present disclosure. The lens module includes a lens barrel, an electronic photosensitive element, and the above optical system. The optical system is mounted in the lens barrel, and the electronic photosensitive element is arranged at the image side of the optical system. The electronic photosensitive element is arranged at the image side of the optical system and used to convert light passing through the first to seventh lenses and incident on the electronic photosensitive element into an electrical signal of an image. In the present disclosure, the first to seventh lenses of the optical system are installed in the lens module, a surface shape and refractive power of each lens of the first to seventh lenses are reasonably set, such that the optical system of the seven-element lens meet both large field angle and miniaturization.

In an implementation, an electronic device is provided according to implementations of the present disclosure. The electronic device includes a housing and the above-mentioned lens module. The lens module is received in the housing. In the present disclosure, the lens module is installed in the electronic device, such that the electronic device can meet both large field angle and miniaturization.

As described above, the optical system with the seven-element lens of the disclosure has a compact space arrangement, thereby realizing a wide-angle imaging and allowing the optical system to be light and thin and have a short overall length. Moreover, the refractive power is reasonably distributed, such that an aberration of the overall optical system is balanced, sensitivity of the optical system is lowered, and mass production and processing can be carried out to meet the current market demand.

BRIEF DESCRIPTION OF THE DRAWINGS

To describe the technical solutions in the implementations of the present disclosure or the related art more clearly, the following briefly introduces the accompanying drawings required for describing the implementations or the related art. Apparently, the accompanying drawings in the following description illustrate some implementations of the present disclosure. Those of ordinary skill in the art may also obtain other drawings based on these accompanying drawings without creative efforts.

FIG. 1a is a schematic structural view of an optical system according an implementation.

FIG. 1b illustrates a longitudinal spherical aberration curve, an astigmatic field curve, and a distortion curve of the optical system of FIG. 1a.

FIG. 2a is a schematic structural view of an optical system according to an implementation.

FIG. 2b illustrates a longitudinal spherical aberration curve, an astigmatic field curve, and a distortion curve of the optical system of FIG. 2a.

FIG. 3a is a schematic structural view of an optical system according an implementation.

FIG. 3b illustrates a longitudinal spherical aberration curve, an astigmatic field curve, and a distortion curve of the optical system of FIG. 3a.

FIG. 4a is a schematic structural view of an optical system according to an implementation.

FIG. 4b illustrates a longitudinal spherical aberration curve, an astigmatic field curve, and a distortion curve of the optical system of FIG. 4a.

FIG. 5a is a schematic structural view of an optical system according to an implementation.

FIG. 5b illustrates a longitudinal spherical aberration curve, an astigmatic field curve, and a distortion curve of the optical system of FIG. 5a.

FIG. 6a is a schematic structural view of an optical system according an implementation.

FIG. 6b illustrates a longitudinal spherical aberration curve, an astigmatic field curve, and a distortion curve of the optical system of FIG. 6a.

FIG. 7a is a schematic structural view of an optical system according to an implementation.

FIG. 7b illustrates a longitudinal spherical aberration curve, an astigmatic field curve, and a distortion curve of the optical system of FIG. 7a.

DETAILED DESCRIPTION OF ILLUSTRATED IMPLEMENTATIONS

Technical solutions in the implementations of the present disclosure will be described clearly and completely hereinafter with reference to the accompanying drawings in the implementations of the present disclosure. Apparently, the described implementations are merely some rather than all implementations of the present disclosure. All other implementations obtained by those of ordinary skill in the art based on the implementations of the present disclosure without creative efforts shall fall within the protection scope of the present disclosure.

A lens module is provided according to an implementation of the present disclosure. The lens module includes a lens barrel, an electronic photosensitive element, and an optical system provided in implementations of the disclosure. First to seventh lenses of the optical system are installed in the lens barrel. The electronic photosensitive element is arranged at an image side of the optical system and used to convert light passing through the first to seventh lenses and incident on the electronic photosensitive element into an electrical signal of an image. The electronic photosensitive element may be a complementary metal oxide semiconductor (CMOS) or a charge-coupled device (CCD). The lens module can be an independent lens of a digital camera or an imaging module integrated on an electronic device such as a smart phone. In the present disclosure, the first to seventh lenses of the optical system are installed in the lens module, a surface shape and refractive power of each lens of the first to seventh lenses are reasonably set, such that the optical system of the seven-element lens meet both large field angle and miniaturization.

An electronic device is provided according to implementations of the present disclosure. The electronic device includes a housing and the lens module provided in implementations of the disclosure. The lens module and the electronic photosensitive element are received in the housing. The electronic device can be a smart phone, a personal digital assistant (PDA), a tablet computer, a smart watch, a drone, an e-book reader, a driving recorder, a wearable device, etc. In the present disclosure, the lens module is installed in the electronic device, such that the electronic device can meet both large field angle and miniaturization.

An optical system is provided according to implementations of the present disclosure. The optical system includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens which are sequentially arranged from an object side to an image side along an optical axis of the optical system. There is an air gap between adjacent ones of the first to seventh lenses.

In implementations of the disclosure, structure and shape of each of the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens are described in detail as follows.

The first lens has a positive refractive power and an object-side surface which is convex near the optical axis. The second lens has a refractive power. The third lens has a refractive power. The fourth lens has a refractive power. The fifth lens has a refractive power. The sixth lens has a positive refractive power. The seventh lens has a negative refractive power and an image-side surface which is concave near the optical axis. The optical system satisfies the following expression: 4≤(Y72*TL)/(ET7*f)≤10. Y72 represents a maximum optical effective radius of the image-side surface of the seventh lens. TL represents a distance along the optical axis from the object-side surface of the first lens to an imaging plane of the optical system. ET7 represents a distance along the optical axis from an object-side surface of the seventh lens at a maximum optical effective radius to the image-side surface of the seventh lens at the maximum optical effective radius. f represents a focal length of the optical system. In the disclosure, a surface shape and the refractive power of each lens of the first to seventh lenses are rationally set, such that the seven-element optical system can meet the requirements of high pixels and good imaging quality. When the optical system satisfies the above expressions, a balance between large field angle and thickness of the optical system can be realized, ensuring the yield of the seventh lens as well as reducing the size of the optical system.

In an implementation, the optical system satisfies the following expression: 2≤TL/EPD≤3. EPD represents an entrance pupil diameter of the optical system. As an example, the optical system satisfies the expression: 2.143≤TL/EPD≤1.294. When the optical system satisfies the above expressions, the total length of the optical system can be reduced and the amount of incident light can be increased.

In an implementation, the optical system satisfies the following expression: 9≤(|AL1S1|+|AL2S1|)/f≤20. AL1S1 represents a maximum value of an acute angle between a tangent plane within a maximum optical effective radius of the object-side surface of the first lens and a plane perpendicular to the optical axis. It is noted that, the tangent plane refers to a plane tangential to the object-side surface of the first lens at a point within the maximum optical effective radius of the object-side surface of the first lens. AL1S2 represents a maximum value of an acute angle between a tangent plane within a maximum optical effective radius of the object-side surface of the second lens and the plane perpendicular to the optical axis. As an example, the optical system satisfies the expression: 9.754≤(|AL1S1|+|AL2S1|)/f≤18.909. When the optical system satisfies the above expressions, production sensitivity of first lens can be reduced and a larger field angle can be achieved. It is noted that, the tangent plane refers to a plane tangential to the object-side surface of the second lens at a point within the maximum optical effective radius of the object-side surface of the second lens.

In an implementation, the optical system satisfies the following expression: 0≤MVd/f≤20. MVd represents an average of Abbe numbers of the first to seventh lenses. As an example, the optical system satisfies the expression: 12.114≤MVd/f≤16.05. When the optical system satisfies the above expressions, chromatic aberration can be balanced, a match between different Abbe numbers and different refractive indexes is realized, and large field angle and good optical imaging performance can be achieved through combining different materials.

In an implementation, the optical system satisfies the following expression: 0≤ET1/(CT1*f)≤1 mm⁻¹. ET1 represents a distance along the optical axis from the object-side surface of the first lens at a maximum optical effective radius to an image-side surface of the first lens at a maximum optical effective radius. CT1 represents a thickness of the first lens along the optical axis. As an example, the optical system satisfies the expression: 0.132 mm⁻¹≤ET1/(CT1*f)≤0.211 mm⁻¹. When the optical system satisfies the above expressions, it is beneficial to molding the first lens.

In an implementation, the optical system satisfies the following expression 0≤ET7/(CT7*f)≤1 mm⁻¹. CT7 represents a thickness of the seventh lens along the optical axis. As an example, the optical system satisfies the expression 0.324≤ET7/(CT7*f)≤0.528 mm⁻¹. When the optical system satisfies the above expression, it is beneficial to molding the seventh lens.

In an implementation, the optical system satisfies the following expression: 0≤EPD/f≤1. EPD represents an entrance pupil diameter of the optical system. As an example, the optical system satisfies the expression: 0.495≤EPD/f≤0.633. When the optical system satisfies the above expressions, a balance between the amount of incident light and a rearward movement of the imaging plane can be achieved, and a large aperture and a large field angle can be realized.

In an implementation, the optical system satisfies the following expression: 0≤(MIN6*MAX7)/(MAX6*MIN7)≤1. MIN6 represents a minimum thickness of the sixth lens along the optical axis within a maximum optical effective radius of an object-side surface of the sixth lens as well as a maximum optical effective radius of an image-side surface of the sixth lens. MAX6 represents a maximum thickness of the sixth lens along the optical axis within the maximum optical effective radius of the object-side surface of the sixth lens as well as the maximum optical effective radius of the image-side surface of the sixth lens. MIN7 represents a minimum thickness of the seventh lens along the optical axis within a maximum optical effective radius of the object-side surface of the seventh lens as well as a maximum optical effective radius of the image-side surface of the seventh lens. MAX7 represents a maximum thickness of the seventh lens along the optical axis within the maximum optical effective radius of the object-side surface of the seventh lens as well as the maximum optical effective radius of the image-side surface of the seventh lens. As an example, the optical system satisfies the expression: 0.15≤(MIN6*MAX7)/(MAX6*MIN7)≤0.364. When the optical system satisfies the above expressions, a yield of injection molding can be improved, and a balance between a large field angle and astigmatism can be realized.

In an implementation, the optical system satisfies the following expression: 0≤(CT5+CT7)/CT6≤2. CT5 represents a thickness of the fifth lens along the optical axis. CT6 represents a thickness of the sixth lens along the optical axis. CT7 represents a thickness of the seventh lens along the optical axis. As an example, the optical system satisfies the expression: 0.903≤(CT5+CT7)/CT6≤1.812. When the optical system satisfies the above expressions, it is beneficial to enlarging the field angle and balancing aberrations.

In an implementation, the optical system satisfies the following expression: 1≤TL/ImgH≤2. ImgH represents half of an image height corresponding to a maximum field angle of the optical system. As an example, the optical system satisfies the expression: 1.324≤TL/ImgH≤1.734. When the optical system satisfies the above expressions, it is beneficial to realizing the miniaturization of the optical system.

Referring to FIG. 1a and FIG. 1b, the optical system in this implementation includes the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6, and the seventh lens L7 which are sequentially arranged from the object side to the image side along the optical axis of the optical system.

The first lens L1 has a positive refractive power. The object-side surface S1 of the first lens L1 is convex near the optical axis and is convex at a circumference. The image-side surface S2 of the first lens L1 is concave near the optical axis and is concave at a circumference.

The second lens L2 has a negative refractive power. The object-side surface S3 of the second lens L2 is convex near the optical axis and is convex at a circumference. The image-side surface S4 of the second lens L2 is concave near the optical axis and is concave at a circumference.

The third lens L3 has a negative refractive power. The object-side surface S5 of the third lens L3 is convex near the optical axis and is concave at a circumference. The image-side surface S6 of the third lens L3 is concave near the optical axis and is convex at a circumference.

The fourth lens L4 has a positive refractive power. The object-side surface S7 of the fourth lens L4 is convex near the optical axis and is convex at a circumference. The image-side surface S8 of the fourth lens L4 is convex near the optical axis and is convex at a circumference.

The fifth lens L5 has a negative refractive power. The object-side surface S9 of the fifth lens L5 is convex near the optical axis and is concave at a circumference. The image-side surface S10 of the fifth lens L5 is concave near the optical axis and is convex at a circumference.

The sixth lens L6 has a positive refractive power. The object-side surface S11 of the sixth lens L6 is convex near the optical axis and is concave at a circumference. The image-side surface S12 of the sixth lens L6 is convex near the optical axis and is convex at a circumference.

The seventh lens L7 has a negative refractive power. The object-side surface S13 of the seventh lens L7 is concave near the optical axis and is convex at a circumference. The image-side surface S14 of the seventh lens L7 is concave near the optical axis and is convex at a circumference.

In an implementation, each lens of the first to seventh lenses (L1 to L8) is made of plastic.

In addition, the optical system further includes an aperture stop (STO), an infrared cut-off filter L8, and the imaging plane S17. The aperture stop STO is arranged at a side of the first lens L1 away from the second lens L2 to control the amount of light entering the lens. In other implementations, the aperture stop STO can also be arranged between two adjacent lenses, or on another lens. The infrared cut-off filter L8 is arranged at an image side of the seventh lens L7 and has an object-side surface S15 and an image-side surface S16. The infrared cut-off filter L8 is used to filter out infrared light so that the light entering the imaging plane S17 is visible light, and the wavelength of visible light is 380 nm-780 nm. The infrared cut-off filter L8 is made of glass and can be coated thereon. The imaging plane S17 is a plane where light reflected by the subject travels through the optical system to form an image.

Table 1a illustrates characteristics of the optical system in this implementation. Each of Y radius, thickness, and focal length is in units of millimeter (mm).

TABLE 1a

Optical system illustrated in FIG. 1a

f = 3.58 mm, FNO = 1.98, FOV = 90.29°

Surface
Surface

Refractive
Abbe
Focal

Number
Name
Shape
Y Radius
Thickness
Material
Index
Number
length

Object

Spherical
Infinity
Infinity

number

STO

Spherical
Infinity
−0.223

S1
First lens
Aspherical
1.942
0.519
Plastic
1.54
56.1
5.68

S2

Aspherical
4.735
0.100

S3
Second lens
Aspherical
3.588
0.230
Plastic
1.67
19.2
−24.57

S4

Aspherical
2.871
0.210

S5
Third lens
Aspherical
4.778
0.259
Plastic
1.64
23.5
−62.76

S6

Aspherical
4.179
0.069

S7
Fourth lens
Aspherical
11.541
0.613
Plastic
1.54
56.1
15.11

S8

Aspherical
−28.056
0.100

S9
Fifth lens
Aspherical
5.974
0.290
Plastic
1.67
19.2
−15.70

S10

Aspherical
3.739
0.157

S11
Sixth lens
Aspherical
3.331
0.720
Plastic
1.54
56.1
1.92

S12

Aspherical
−1.402
0.292

S13
Seventh lens
Aspherical
−3.848
0.360
Plastic
1.53
55.8
−1.82

S14

Aspherical
1.35
0.564

S15
Infrared cut-
Spherical
Infinity
0.210
Glass
1.52
64.2

S16
off filter
Spherical
Infinity
0.269

S17

Spherical
Infinity
0.000

Note:

The reference wavelength is 587.5618 nm

f represents the focal length of the optical system. FNO represents the F-number of the optical system. FOV is a field angle of the optical system.

In this implementation, the object-side surface and the image-side surface of each of the first to seventh lenses (L1, L2, L3, L4, L5, L6, L7) are aspherical. A surface shape of each aspherical lens can be defined but not limited to the following aspherical formula:

$x = \frac{{ch}^{2}}{1 + \sqrt{1 - (k + 1) c^{2} h^{2}}} + \sum {Aih}^{i}$

x represents a distance (sag) along the optical axis from a vertex of the aspherical surface to a position on the aspherical surface at a height h. c represents the paraxial curvature of the aspherical surface, and is the inverse of the Y radius (that is, c=1/R, where R represents the Y radius in the Table 1a). k represents the conic coefficient. Ai represents the i-th order correction coefficient of the aspherical surface. Table 1b shows higher-order coefficients A4, A6, A8, A10, A12, A14, A16, A18, and A20 of each of aspherical lens surfaces S1 to S14 of the optical system illustrated in FIG. 1a.

TABLE 1b

Optical system of FIG. 1a

Aspherical coefficients

Surface

Number
S1
S2
S3
S4
S5
S6
S7

K
6.31E−02
−8.28E+00
−2.72E+01
−2.06E+00
−6.55E+01
−3.01E+01
6.53E+01

A4
−8.15E−04
−4.11E−02
−4.23E−02
−6.40E−02
−2.26E−03
−8.77E−02
−1.64E−01

A6
4.58E−02
−1.58E−02
5.66E−02
1.12E−01
2.32E−01
5.74E−01
5.22E−01

A8
−3.22E−01
3.17E−01
−4.23E−01
−5.48E−01
−2.09E+00
−2.06E+00
−1.02E+00

A10
1.42E+00
−1.30E+00
1.84E+00
2.22E+00
7.72E+00
4.43E+00
1.05E+00

A12
−3.73E+00
3.34E+00
−4.48E+00
−5.50E+00
−1.75E+01
−6.38E+00
−2.24E−01

A14
5.89E+00
−5.52E+00
6.36E+00
8.31E+00
2.48E+01
6.16E+00
−6.87E−01

A16
−5.45E+00
5.37E+00
−5.50E+00
−7.69E+00
−2.15E+01
−3.86E+00
7.61E−01

A18
2.70E+00
−2.77E+00
2.69E+00
4.00E+00
1.04E+01
1.41E+00
−3.23E−01

A20
−5.41E−01
5.85E−01
−5.59E−01
−8.82E−01
−2.11E+00
−2.26E−01
5.04E−02

Surface

Number
S8
S9
S10
S11
S12
S13
S14

K
−9.90E+01
−5.07E+01
−2.23E+01
−3.12E+01
−6.89E+00
−1.08E+01
−6.72E+00

A4
−9.47E−02
1.94E−02
−3.15E−02
−4.14E−02
−7.10E−02
−5.40E−02
−4.94E−02

A6
−2.47E−01
−3.53E−01
−9.87E−02
5.40E−02
1.67E−01
−2.15E−02
6.83E−03

A8
1.18E+00
1.08E+00
2.99E−01
−7.55E−02
−1.71E−01
3.08E−02
4.51E−03

A10
−2.66E+00
−1.79E+00
−3.99E−01
5.70E−02
1.08E−01
−1.20E−02
−2.91E−03

A12
3.45E+00
1.76E+00
2.94E−01
−3.51E−02
−4.48E−02
2.57E−03
7.81E−04

A14
−2.76E+00
−1.08E+00
−1.29E−01
1.72E−02
1.24E−02
−3.38E−04
−1.18E−04

A16
1.37E+00
4.12E−01
3.39E−02
−5.72E−03
−2.17E−03
2.75E−05
1.04E−05

A18
−3.79E−01
−8.95E−02
−4.87E−03
1.11E−03
2.16E−04
−1.28E−06
−4.92E−07

A20
4.52E−02
8.43E−03
2.96E−04
−9.06E−05
−9.27E−06
2.60E−08
9.68E−09

FIG. 1b illustrates a longitudinal spherical aberration curve, an astigmatic field curve, and a distortion curve of the optical system of FIG. 1a. The longitudinal spherical aberration curve represents a focus deviation of each of light rays with different wavelengths after passing through each lens of the optical system. The astigmatic field curve represents tangential image surface curvature and sagittal image surface curvature. The distortion curve represents magnitudes of distortions corresponding to different field angles. According to the longitudinal spherical aberration curves illustrated in FIG. 1b, the longitudinal spherical aberration of the optical system for light rays with wavelengths of 470.0000 nm, 510.0000 nm, 587.5618 nm, 610.0000 nm, and 650.0000 nm is ranged from −0.025 mm to 0.01 mm. According to the astigmatic field curves illustrated in FIG. 1b, the astigmatism of the optical system for a light ray with the wavelength of 587.5618 nm in the tangential and sagittal directions is ranged from −0.03 mm to 0.03 mm. According to the distortion curves illustrated in FIG. 1b, the distortion of the optical system for the light ray with the wavelength of 587.5618 nm is ranged from 0.0% and 2.0%. As illustrated in FIG. 1b, it is clear that the optical system of FIG. 1a can achieve good imaging quality.

Referring to FIG. 2a and FIG. 2b, the optical system in this implementation includes the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6, and the seventh lens L7 which are sequentially arranged from the object side to the image side along the optical axis of the optical system.

The second lens L2 has a negative refractive power. The object-side surface S3 of the second lens L2 is convex near the optical axis and is concave at a circumference. The image-side surface S4 of the second lens L2 is concave near the optical axis and is convex at a circumference.

The third lens L3 has a positive refractive power. The object-side surface S5 of the third lens L3 is convex near the optical axis and is concave at a circumference. The image-side surface S6 of the third lens L3 is concave near the optical axis and is convex at a circumference.

The fourth lens L4 has a negative refractive power. The object-side surface S7 of the fourth lens L4 is concave near the optical axis and is concave at a circumference. The image-side surface S8 of the fourth lens L4 is concave near the optical axis and is convex at a circumference.

The fifth lens L5 has a positive refractive power. The object-side surface S9 of the fifth lens L5 is convex near the optical axis and is concave at a circumference. The image-side surface S10 of the fifth lens L5 is concave near the optical axis and is convex at a circumference.

The other structures of the optical system of FIG. 2a are identical with the optical system of FIG. 1a, reference can be made to the optical system of FIG. 1a.

Table 2a illustrates characteristics of the optical system in this implementation. Each of Y radius, thickness, and focal length is in units of millimeter (mm).

TABLE 2a

Optical system of FIG. 2a

f = 3.55 mm, FNO = 2.02, FOV = 90.60°

Surface
Surface

Refractive
Abbe
Focal

Number
Name
Shape
Y Radius
Thickness
Material
Index
Number
length

Object

Spherical
Infinity
Infinity

number

STO

Spherical
Infinity
−0.180

S1
First lens
Aspherical
1.932
0.632
Plastic
1.54
56.1
5.22

S2

Aspherical
5.347
0.227

S3
Second lens
Aspherical
4.96
0.276
Plastic
1.67
19.2
−24.06

S4

Aspherical
3.71
0.091

S5
Third lens
Aspherical
10.916
0.322
Plastic
1.67
19.2
58.25

S6

Aspherical
14.962
0.041

S7
Fourth lens
Aspherical
−30.874
0.577
Plastic
1.53
55.8
−32.65

S8

Aspherical
40.479
0.100

S9
Fifth lens
Aspherical
1.747
0.290
Plastic
1.67
19.2
44.56

S10

Aspherical
1.732
0.100

S11
Sixth lens
Aspherical
3.5
0.491
Plastic
1.64
23.5
2.44

S12

Aspherical
−2.66
0.328

S13
Seventh lens
Aspherical
−12.421
0.360
Plastic
1.53
55.8
−2.26

S14

Aspherical
1.35
0.542

S15
Infrared cut-
Spherical
Infinity
0.210
Glass
1.52
64.2

S16
off filter
Spherical
Infinity
0.230

S17

Spherical
Infinity
0.000

Note:

The reference wavelength is 587.5618 nm

Each parameter in Table 2a represents the same meaning as that in the optical system of FIG. 1a.

Table 2b shows higher-order coefficients that can be used for each aspherical lens surface of the optical system of FIG. 2a, where a shape of each aspherical lens surface can be defined by the formula given in the optical system of FIG. 1a.

TABLE 2b

Optical system of FIG. 2a

Aspherical coefficients

Surface

Number
S1
S2
S3
S4
S5
S6
S7

K
−6.67E−01
−9.07E+01
−9.90E+01
−1.25E+01
5.78E+01
9.90E+01
−9.90E+01

A4
5.17E−03
1.58E−02
−6.50E−02
3.47E−03
1.15E−01
−1.06E−03
−1.45E−01

A6
−1.22E−02
−2.50E−01
−1.26E−01
−3.74E−01
−5.41E−01
7.76E−01
1.68E+00

A8
4.34E−02
9.11E−01
−5.40E−01
1.23E+00
1.26E+00
−4.59E+00
−7.05E+00

A10
−8.16E−02
−3.16E+00
3.14E+00
−2.99E+00
−1.29E+00
1.21E+01
1.54E+01

A12
−9.22E−02
7.30E+00
−8.42E+00
4.93E+00
−1.07E+00
−1.88E+01
−2.00E+01

A14
5.21E−01
−1.09E+01
1.35E+01
−5.28E+00
4.45E+00
1.83E+01
1.63E+01

A16
−7.43E−01
1.00E+01
−1.30E+01
3.48E+00
−5.06E+00
−1.10E+01
−8.17E+00

A18
4.20E−01
−5.18E+00
6.99E+00
−1.34E+00
2.62E+00
3.76E+00
2.33E+00

A20
−6.81E−02
1.17E+00
−1.61E+00
2.38E−01
−5.23E−01
−5.59E−01
−2.90E−01

Surface

Number
S8
S9
S10
S11
S12
S13
S14

K
−9.90E+01
−2.36E+01
−1.90E+01
−6.89E+00
−1.35E+01
−2.35E+01
−4.94E+00

A4
−1.05E+00
−5.69E−01
−5.55E−03
9.54E−02
1.90E−01
−3.67E−02
−9.79E−02

A6
3.86E+00
1.97E+00
4.03E−02
−8.58E−02
−4.12E−03
−1.26E−03
5.27E−02

A8
−9.91E+00
−4.40E+00
−3.19E−01
−9.36E−02
−1.16E−01
−3.21E−03
−2.39E−02

A10
1.64E+01
5.80E+00
4.16E−01
2.32E−01
7.07E−02
5.73E−03
7.53E−03

A12
−1.79E+01
−4.77E+00
−2.56E−01
−2.47E−01
−1.72E−02
−2.32E−03
−1.52E−03

A14
1.28E+01
2.50E+00
7.96E−02
1.44E−01
1.08E−03
4.55E−04
1.92E−04

A16
−5.76E+00
−8.21E−01
−9.34E−03
−4.69E−02
3.15E−04
−4.85E−05
−1.44E−05

A18
1.47E+00
1.53E−01
−6.75E−04
7.93E−03
−6.58E−05
2.72E−06
5.82E−07

A20
−1.60E−01
−1.20E−02
1.83E−04
−5.48E−04
3.79E−06
−6.30E−08
−9.76E−09

FIG. 2b illustrates a longitudinal spherical aberration curve, an astigmatic field curve, and a distortion curve of the optical system of FIG. 2a. According to the longitudinal spherical aberration curves illustrated in FIG. 2b, the longitudinal spherical aberration of the optical system for light rays with wavelengths of 470.0000 nm, 510.0000 nm, 587.5618 nm, 610.0000 nm, and 650.0000 nm is ranged from −0.075 mm to 0.03 mm. According to the astigmatic field curves illustrated in FIG. 2b, the astigmatism of the optical system for a light ray with the wavelength of 587.5618 nm in the tangential and sagittal directions is ranged from −0.01 mm to 0.04 mm. According to the distortion curves illustrated in FIG. 2b, the distortion of the optical system for the light ray with the wavelength of 587.5618 nm is ranged from 0.0% and 2.0%. As illustrated in FIG. 2b, the optical system of FIG. 2a can achieve good imaging quality.

Referring to FIG. 3a and FIG. 3b, the optical system in this implementation includes the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6, and the seventh lens L7 which are sequentially arranged from the object side to the image side along the optical axis of the optical system.

The fourth lens L4 has a positive refractive power. The object-side surface S7 of the fourth lens L4 is convex near the optical axis and is concave at a circumference. The image-side surface S8 of the fourth lens L4 is convex near the optical axis and is convex at a circumference.

The fifth lens L5 has a negative refractive power. The object-side surface S9 of the fifth lens L5 is concave near the optical axis and is concave at a circumference. The image-side surface S10 of the fifth lens L5 is concave near the optical axis and is convex at a circumference.

The seventh lens L7 has a negative refractive power. The object-side surface S13 of the seventh lens L7 is concave near the optical axis and is concave at a circumference. The image-side surface S14 of the seventh lens L7 is concave near the optical axis and is convex at a circumference.

The other structures of the optical system of FIG. 3a are identical with the optical system of FIG. 1a, reference can be made to the optical system of FIG. 1a.

Table 3a illustrates characteristics of the optical system in this implementation. Each of Y radius, thickness, and focal length is in units of millimeter (mm).

TABLE 3a

Optical system of FIG. 3a

f = 3.67 mm, FNO = 1.58, FOV = 80.40°

Surface
Surface

Refractive
Abbe
Focal

Number
Name
Shape
Y Radius
Thickness
Material
Index
Number
length

Object

Spherical
Infinity
Infinity

number

STO

Spherical
Infinity
−0.413

S1
First lens
Aspherical
1.877
0.723
Plastic
1.54
56.1
5.37

S2

Aspherical
4.54
0.110

S3
Second lens
Aspherical
3.287
0.260
Plastic
1.67
19.2
−33.07

S4

Aspherical
2.772
0.249

S5
Third lens
Aspherical
6.833
0.295
Plastic
1.67
19.2
−43.30

S6

Aspherical
5.436
0.034

S7
Fourth lens
Aspherical
9.236
0.594
Plastic
1.54
56.1
10.25

S8

Aspherical
−13.76
0.100

S9
Fifth lens
Aspherical
−128.372
0.280
Plastic
1.67
19.2
−6.72

S10

Aspherical
4.684
0.110

S11
Sixth lens
Aspherical
1.87
0.633
Plastic
1.54
56.1
2.11

S12

Aspherical
−2.626
0.290

S13
Seventh lens
Aspherical
−4.61
0.396
Plastic
1.53
55.8
−2.18

S14

Aspherical
1.608
0.483

S15
Infrared cut-
Spherical
Infinity
0.210
Glass
1.52
64.2

S16
off filter
Spherical
Infinity
0.214

S17

Spherical
Infinity
0.000

Note:

The reference wavelength is 587.5618 nm

Each parameter in Table 3a represents the same meaning as that in the optical system of FIG. 1a.

Table 3b shows higher-order coefficients that can be used for each aspherical lens surface of the optical system of FIG. 3a, where a shape of each aspherical lens surface can be defined by the formula given in the optical system of FIG. 1a.

TABLE 3b

Optical system of FIG. 3a

Aspherical coefficients

Surface

Number
S1
S2
S3
S4
S5
S6
S7

K
2.68E−02
−2.99E+01
−7.96E+01
−5.89E+00
−7.82E+01
−2.06E+01
2.45E+01

A4
−3.32E−03
−4.41E−02
9.40E−02
−7.30E−02
2.19E−02
7.69E−03
−4.87E−02

A6
3.50E−02
−9.26E−02
−7.49E−01
2.07E−02
−2.25E−01
−1.69E−01
−1.08E−01

A8
−1.51E−01
8.03E−01
2.36E+00
−1.01E−01
8.53E−01
6.79E−01
5.79E−01

A10
4.24E−01
−2.57E+00
−5.07E+00
7.31E−01
−2.80E+00
−1.67E+00
−1.15E+00

A12
−7.19E−01
4.90E+00
7.72E+00
−1.94E+00
5.51E+00
2.27E+00
1.03E+00

A14
7.52E−01
−5.81E+00
−8.19E+00
2.74E+00
−6.52E+00
−1.87E+00
−2.91E−01

A16
−4.70E−01
4.22E+00
5.69E+00
−2.25E+00
4.45E+00
9.12E−01
−1.84E−01

A18
1.62E−01
−1.72E+00
−2.31E+00
1.01E+00
−1.58E+00
−2.35E−01
1.55E−01

A20
−2.36E−02
3.00E−01
4.12E−01
−1.91E−01
2.24E−01
2.31E−02
−3.27E−02

Surface

Number
S8
S9
S10
S11
S12
S13
S14

K
−7.98E+01
9.90E+01
−9.90E+01
−1.36E+01
−9.39E+00
−5.77E+00
−7.90E+00

A4
5.74E−02
9.50E−02
−1.86E−01
−8.17E−02
7.71E−02
−1.98E−01
−1.08E−01

A6
−6.38E−01
−5.62E−01
2.55E−01
1.30E−01
−6.97E−02
1.28E−01
7.23E−02

A8
1.28E+00
1.19E+00
−3.60E−01
−1.43E−01
8.36E−02
−5.79E−02
−3.54E−02

A10
−1.79E+00
−1.89E+00
3.65E−01
5.86E−02
−6.47E−02
2.93E−02
1.22E−02

A12
1.76E+00
2.10E+00
−2.64E−01
2.04E−02
2.17E−02
−1.18E−02
−2.96E−03

A14
−1.12E+00
−1.48E+00
1.40E−01
−4.27E−02
−1.73E−03
2.99E−03
4.87E−04

A16
4.51E−01
6.37E−01
−5.08E−02
2.25E−02
−6.91E−04
−4.51E−04
−5.21E−05

A18
−1.10E−01
−1.53E−01
1.07E−02
−5.08E−03
1.73E−04
3.72E−05
3.25E−06

A20
1.29E−02
1.58E−02
−9.51E−04
4.24E−04
−1.17E−05
−1.30E−06
−8.90E−08

FIG. 3b illustrates a longitudinal spherical aberration curve, an astigmatic field curve, and a distortion curve of the optical system of FIG. 3a. According to the longitudinal spherical aberration curves illustrated in FIG. 3b, the longitudinal spherical aberration of the optical system for light rays with wavelengths of 470.0000 nm, 510.0000 nm, 587.5618 nm, 610.0000 nm, and 650.0000 nm is ranged from −0.02 mm to 0.02 mm. According to the astigmatic field curves illustrated in FIG. 3b, the astigmatism of the optical system for a light ray with the wavelength of 587.5618 nm in the tangential and sagittal directions is ranged from −0.02 mm to 0.02 mm. According to the distortion curves illustrated in FIG. 3b, the distortion of the optical system for the light ray with the wavelength of 587.5618 nm is ranged from 0.0% and 2.0%. As illustrated in FIG. 3b, the optical system of FIG. 3a can achieve good imaging quality.

Referring to FIG. 4a and FIG. 4b, the optical system in this implementation includes the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6, and the seventh lens L7 which are sequentially arranged from the object side to the image side along the optical axis of the optical system.

The second lens L2 has a positive refractive power. The object-side surface S3 of the second lens L2 is convex near the optical axis and is convex at a circumference. The image-side surface S4 of the second lens L2 is concave near the optical axis and is concave at a circumference.

The third lens L3 has a negative refractive power. The object-side surface S5 of the third lens L3 is concave near the optical axis and is concave at a circumference. The image-side surface S6 of the third lens L3 is convex near the optical axis and is convex at a circumference.

The sixth lens L6 has a positive refractive power. The object-side surface S11 of the sixth lens L6 is concave near the optical axis and is concave at a circumference. The image-side surface S12 of the sixth lens L6 is convex near the optical axis and is convex at a circumference.

The other structures of the optical system of the optical system of FIG. 4a are identical with the optical system of FIG. 1a, reference can be made to the optical system of FIG. 1a.

Table 4a illustrates characteristics of the optical system in this implementation. Each of Y radius, thickness, and focal length is in units of millimeter (mm).

TABLE 4a

Optical system of FIG. 4a

f = 3.82 mm, FNO = 1.65, FOV = 84.40°

Surface
Surface

Refractive
Abbe
Focal

Number
Name
Shape
Y Radius
Thickness
Material
Index
Number
length

Object

Spherical
Infinity
Infinity

number

STO

Spherical
Infinity
−0.382

S1
First lens
Aspherical
2.051
0.641
Plastic
1.54
56.1
6.73

S2

Aspherical
4.145
0.095

S3
Second lens
Aspherical
3.59
0.280
Plastic
1.67
19.2
30.67

S4

Aspherical
4.212
0.293

S5
Third lens
Aspherical
−10.595
0.300
Plastic
1.65
21.5
−25.51

S6

Aspherical
−29.587
0.050

S7
Fourth lens
Aspherical
21.631
0.598
Plastic
1.54
56.1
15.18

S8

Aspherical
−13.227
0.124

S9
Fifth lens
Aspherical
2.755
0.330
Plastic
1.67
19.2
19.18

S10

Aspherical
3.337
0.280

S11
Sixth lens
Aspherical
−37.864
0.632
Plastic
1.54
56.1
2.68

S12

Aspherical
−1.41
0.298

S13
Seventh lens
Aspherical
−3.564
0.360
Plastic
1.53
55.8
−1.82

S14

Aspherical
1.387
0.495

S15
Infrared cut-
Spherical
Infinity
0.210
Glass
1.52
64.2

S16
off filter
Spherical
Infinity
0.206

S17

Spherical
Infinity
0.000

Note:

The reference wavelength is 587.5618 nm

Each parameter in Table 4a represents the same meaning as that in the optical system of FIG. 1a.

Table 4b shows higher-order coefficients that can be used for each aspherical lens surface of the optical system of FIG. 4a, where a shape of each aspherical lens surface can be defined by the formula given in the optical system of FIG. 1a.

TABLE 4b

Optical system of FIG. 4a

Aspherical coefficients

Surface

Number
S1
S2
S3
S4
S5
S6
S7

K
2.59E−01
−8.92E+00
−4.05E+01
−6.83E+00
−5.22E+01
2.03E+01
9.90E+01

A4
2.04E−03
−5.03E−02
−2.29E−02
−6.87E−02
−5.45E−02
−1.08E−01
−1.41E−01

A6
1.13E−03
−7.40E−02
−1.54E−01
1.13E−02
1.67E−01
5.07E−01
6.54E−01

A8
−7.25E−02
6.16E−01
1.81E−01
−3.18E−01
−1.00E+00
−1.19E+00
−1.48E+00

A10
4.08E−01
−1.84E+00
4.90E−01
1.50E+00
3.10E+00
1.41E+00
1.99E+00

A12
−9.70E−01
3.24E+00
−2.40E+00
−3.51E+00
−6.17E+00
−6.23E−01
−1.68E+00

A14
1.26E+00
−3.52E+00
4.46E+00
4.74E+00
7.96E+00
−4.71E−01
8.55E−01

A16
−9.24E−01
2.36E+00
−4.38E+00
−3.67E+00
−6.40E+00
7.68E−01
−2.40E−01

A18
3.60E−01
−9.32E−01
2.22E+00
1.48E+00
2.90E+00
−3.86E−01
2.84E−02

A20
−5.78E−02
1.75E−01
−4.53E−01
−2.19E−01
−5.58E−01
7.10E−02
−1.19E−04

Surface

Number
S8
S9
S10
S11
S12
S13
S14

K
3.55E+01
−2.36E+01
−1.35E+01
−9.90E+01
−7.19E+00
−6.84E+00
−9.16E+00

A4
−1.57E−01
7.12E−02
1.36E−01
1.15E−01
−2.88E−03
−1.20E−01
−7.49E−02

A6
2.27E−01
−2.64E−01
−3.20E−01
−9.95E−02
5.37E−02
5.90E−02
3.71E−02

A8
−4.23E−01
3.56E−01
3.39E−01
4.37E−02
−2.29E−02
−2.79E−02
−1.45E−02

A10
7.47E−01
−3.03E−01
−2.21E−01
−2.27E−02
−1.19E−02
1.54E−02
4.06E−03

A12
−1.03E+00
1.62E−01
8.68E−02
1.09E−02
1.23E−02
−5.40E−03
−7.96E−04

A14
9.27E−01
−5.91E−02
−1.93E−02
−4.53E−03
−4.11E−03
1.09E−03
1.04E−04

A16
−5.05E−01
1.51E−02
1.85E−03
1.39E−03
6.90E−04
−1.27E−04
−8.50E−06

A18
1.51E−01
−2.42E−03
5.26E−05
−2.31E−04
−5.87E−05
7.98E−06
3.97E−07

A20
−1.89E−02
1.61E−04
−1.69E−05
1.50E−05
2.01E−06
−2.10E−07
−8.17E−09

FIG. 4b illustrates a longitudinal spherical aberration curve, an astigmatic field curve, and a distortion curve of the optical system of FIG. 4a. According to the longitudinal spherical aberration curves illustrated in FIG. 4b, the longitudinal spherical aberration of the optical system for light rays with wavelengths of 470.0000 nm, 510.0000 nm, 587.5618 nm, 610.0000 nm, and 650.0000 nm is ranged from −0.06 mm to 0.02 mm. According to the astigmatic field curves illustrated in FIG. 4b, the astigmatism of the optical system for a light ray with the wavelength of 587.5618 nm in the tangential and sagittal directions is ranged from −0.02 mm to 0.02 mm. According to the distortion curves illustrated in FIG. 4b, the distortion of the optical system for the light ray with the wavelength of 587.5618 nm is ranged from 0.0% and 2.0%. As illustrated in FIG. 4b, the optical system of FIG. 4a can achieve good imaging quality.

Referring to FIG. 5a and FIG. 5b, the optical system in this implementation includes the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6, and the seventh lens L7 which are sequentially arranged from the object side to the image side along the optical axis of the optical system.

The first lens L1 has a positive refractive power. The object-side surface S1 of the first lens L1 is convex near the optical axis and is convex at a circumference. The image-side surface S2 of the first lens L1 is convex near the optical axis and is convex at a circumference.

The second lens L2 has a negative refractive power. The object-side surface S3 of the second lens L2 is concave near the optical axis and is concave at a circumference. The image-side surface S4 of the second lens L2 is concave near the optical axis and is convex at a circumference.

The third lens L3 has a positive refractive power. The object-side surface S5 of the third lens L3 is convex near the optical axis and is convex at a circumference. The image-side surface S6 of the third lens L3 is concave near the optical axis and is concave at a circumference.

The fifth lens L5 has a positive refractive power. The object-side surface S9 of the fifth lens L5 is convex near the optical axis and is convex at a circumference. The image-side surface S10 of the fifth lens L5 is concave near the optical axis and is concave at a circumference.

The sixth lens L6 has a positive refractive power. The object-side surface S11 of the sixth lens L6 is convex near the optical axis and is concave at a circumference. The image-side surface S12 of the sixth lens L6 is concave near the optical axis and is convex at a circumference.

The seventh lens L7 has a negative refractive power. The object-side surface S13 of the seventh lens L7 is convex near the optical axis and is convex at a circumference. The image-side surface S14 of the seventh lens L7 is concave near the optical axis and is convex at a circumference.

The other structures of the optical system of FIG. 5a are identical with the optical system of FIG. 1a, reference can be made to the optical system of FIG. 1a.

Table 5a illustrates characteristics of the optical system in this implementation. Each of Y radius, thickness, and focal length is in units of millimeter (mm).

TABLE 5a

Optical system of FIG. 5a

f = 4.08 mm, FNO = 1.95, FOV = 80.80°

Surface
Surface

Refractive
Abbe
Focal

Number
Name
Shape
Y Radius
Thickness
Material
Index
Number
length

Object

Spherical
Infinity
Infinity

number

STO

Spherical
Infinity
−0.152

S1
First lens
Aspherical
3.146
0.793
Plastic
1.54
56.1
5.15

S2

Aspherical
−23.33
0.119

S3
Second lens
Aspherical
−56.237
0.310
Plastic
1.67
19.2
−6.76

S4

Aspherical
4.949
0.124

S5
Third lens
Aspherical
2.819
0.438
Plastic
1.67
19.2
20.57

S6

Aspherical
3.321
0.291

S7
Fourth lens
Aspherical
101.398
0.750
Plastic
1.54
56.1
24.34

S8

Aspherical
−15.197
0.249

S9
Fifth lens
Aspherical
8.011
0.410
Plastic
1.67
19.2
18.92

S10

Aspherical
21.24
0.100

S11
Sixth lens
Aspherical
2.596
0.538
Plastic
1.54
56.1
5.12

S12

Aspherical
35.33
0.132

S13
Seventh lens
Aspherical
2.59
0.565
Plastic
1.53
55.8
−4.62

S14

Aspherical
1.168
0.713

S15
Infrared cut-
Spherical
Infinity
0.210
Glass
1.52
64.2

S16
off filter
Spherical
Infinity
0.379

S17

Spherical
Infinity
0.000

Note:

The reference wavelength is 587.5618 nm

Each parameter in Table 5a represents the same meaning as that in the optical system of FIG. 1a.

Table 5b shows higher-order coefficients that can be used for each aspherical lens surface of the optical system of FIG. 5a, where a shape of each aspherical lens surface can be defined by the formula given in the optical system of FIG. 1a.

TABLE 5b

Optical system of FIG. 5a

Aspherical coefficients

Surface

Number
S1
S2
S3
S4
S5
S6
S7

K
−1.83E+00
9.90E+01
−9.90E+01
−4.63E+00
−4.15E+01
−2.36E+01
9.90E+01

A4
−5.61E−04
−1.72E−02
−4.38E−03
−7.55E−02
7.36E−02
6.98E−03
−7.21E−02

A6
−1.20E−02
1.19E−02
1.17E−01
1.89E−01
−2.78E−01
2.05E−02
1.38E−01

A8
1.59E−02
−3.58E−02
−4.49E−01
−3.53E−01
4.74E−01
−1.56E−01
−1.85E−01

A10
1.00E−02
−1.64E−01
8.83E−01
4.08E−01
−6.42E−01
2.71E−01
1.49E−01

A12
−9.06E−02
6.57E−01
−1.14E+00
−2.86E−01
6.23E−01
−2.74E−01
−6.19E−02

A14
1.45E−01
−1.06E+00
9.24E−01
8.13E−02
−4.17E−01
1.72E−01
−3.05E−03

A16
−1.09E−01
8.84E−01
−4.66E−01
2.50E−02
1.83E−01
−6.46E−02
1.40E−02

A18
3.84E−02
−3.72E−01
1.41E−01
−2.18E−02
−4.54E−02
1.35E−02
−4.89E−03

A20
−4.73E−03
6.21E−02
−2.08E−02
3.79E−03
4.75E−03
−1.19E−03
5.43E−04

Surface

Number
S8
S9
S10
S11
S12
S13
S14

K
7.34E+01
4.10E+00
8.99E+01
−9.73E+00
−6.20E+01
−1.65E+01
−3.38E+00

A4
−2.19E−01
−6.75E−02
1.83E−02
5.47E−03
−8.51E−02
−1.41E−01
−5.49E−02

A6
2.99E−01
2.25E−01
1.14E−01
−2.52E−02
1.17E−01
1.17E−01
1.95E−02

A8
−3.89E−01
−3.27E−01
−1.96E−01
1.89E−02
−6.79E−02
−6.17E−02
−5.11E−03

A10
3.51E−01
2.52E−01
1.46E−01
−1.01E−02
2.25E−02
2.05E−02
7.71E−04

A12
−2.15E−01
−1.18E−01
−6.31E−02
3.40E−03
−4.68E−03
−4.28E−03
−3.83E−05

A14
9.15E−02
3.44E−02
1.68E−02
−6.63E−04
6.30E−04
5.68E−04
−6.63E−06

A16
−2.66E−02
−5.96E−03
−2.68E−03
4.80E−05
−5.29E−05
−4.65E−05
1.27E−06

A18
4.85E−03
5.48E−04
2.34E−04
4.12E−06
2.51E−06
2.15E−06
−8.33E−08

A20
−4.09E−04
−1.96E−05
−8.55E−06
−6.09E−07
−5.19E−08
−4.28E−08
2.01E−09

FIG. 5b illustrates a longitudinal spherical aberration curve, an astigmatic field curve, and a distortion curve of the optical system of FIG. 5a. According to the longitudinal spherical aberration curves illustrated in FIG. 5b, the longitudinal spherical aberration of the optical system for light rays with wavelengths of 470.0000 nm, 510.0000 nm, 587.5618 nm, 610.0000 nm, and 650.0000 nm is ranged from −0.025 mm to 0.02 mm. According to the astigmatic field curves illustrated in FIG. 5b, the astigmatism of the optical system for a light ray with the wavelength of 587.5618 nm in the tangential and sagittal directions is ranged from −0.01 mm to 0.03 mm. According to the distortion curves illustrated in FIG. 5b, the distortion of the optical system for the light ray with the wavelength of 587.5618 nm is ranged from 0.0% and 2.0%. As illustrated in FIG. 5b, the optical system of FIG. 5a can achieve good imaging quality.

Referring to FIG. 6a and FIG. 6b, the optical system in this implementation includes the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6, and the seventh lens L7 which are sequentially arranged from the object side to the image side along the optical axis of the optical system.

The third lens L3 has a negative refractive power. The object-side surface S5 of the third lens L3 is convex near the optical axis and is convex at a circumference. The image-side surface S6 of the third lens L3 is concave near the optical axis and is concave at a circumference.

The fourth lens L4 has a positive refractive power. The object-side surface S7 of the fourth lens L4 is convex near the optical axis and is convex at a circumference. The image-side surface S8 of the fourth lens L4 is concave near the optical axis and is concave at a circumference.

The fifth lens L5 has a negative refractive power. The object-side surface S9 of the fifth lens L5 is convex near he optical axis and is concave at a circumference. The image-side surface S10 of the fifth lens L5 is concave near the optical axis and is convex at a circumference.

The sixth lens L6 has a positive refractive power. The object-side surface S11 of the sixth lens L6 is convex near the optical axis and is convex at a circumference. The image-side surface 12 of the sixth lens L6 is convex near the optical axis and is concave at a circumference.

The seventh lens L7 has a negative refractive power. The object-side surface 13 of the seventh lens L7 is concave near the optical axis and is convex at a circumference. The image-side surface 14 of the seventh lens L7 is concave near the optical axis and is convex at a circumference.

The other structures of the optical system of FIG. 6a are identical with the optical system of FIG. 1a, reference can be made to the optical system of FIG. 1a.

Table 6a illustrates characteristics of the optical system in this implementation. Each of Y radius thickness and focal length is in units of millimeter (mm).

TABLE 6a

Optical system of FIG. 6a

f = 4.08 mm, FNO = 1.95, FOV = 80.80°

Surface
Surface

Refractive
Abbe
Focal

Number
Name
Shape
Y Radius
Thickness
Material
Index
Number
length

Object

Spherical
Infinity
Infinity

number

STO

Spherical
Infinity
−0.197

S1
First lens
Aspherical
1.607
0.532
Plastic
1.54
56.1
3.97

S2

Aspherical
5.53
0.100

S3
Second lens
Aspherical
3.126
0.230
Plastic
1.67
19.2
−11.10

S4

Aspherical
2.137
0.161

S5
Third lens
Aspherical
4.332
0.261
Plastic
1.64
23.5
−157.59

S6

Aspherical
4.055
0.047

S7
Fourth lens
Aspherical
7.771
0.400
Plastic
1.54
56.1
45.96

S8

Aspherical
11.069
0.100

S9
Fifth lens
Aspherical
4.93
0.290
Plastic
1.67
19.2
−10.31

S10

Aspherical
2.811
0.068

S11
Sixth lens
Aspherical
2.447
0.670
Plastic
1.54
56.1
1.37

S12

Aspherical
−0.968
0.134

S13
Seventh lens
Aspherical
−4.955
0.330
Plastic
1.53
55.8
−1.36

S14

Aspherical
0.87
0.473

S15
Infrared cut-
Spherical
Infinity
0.210
Glass
1.52
64.2

S16
off filter
Spherical
Infinity
0.244

S17

Spherical
Infinity
0.000

Note:

The reference wavelength is 587.5618 nm

Each parameter in Table 6a represents the same meaning as that in the optical system of FIG. 1a.

Table 6b shows higher-order coefficients that can be used for each aspherical lens surface of the optical system of FIG. 6a, where a shape of each aspherical lens surface can be defined by the formula given in the optical system of FIG. 1a.

TABLE 6b

Optical system of FIG. 6a

Aspherical coefficients

Surface

Number
S1
S2
S3
S4
S5
S6
S7

K
2.00E−02
−1.40E+01
−2.76E+01
−2.86E+00
−5.38E+01
−2.60E+01
5.19E+01

A4
−1.88E−03
−7.09E−02
−9.71E−02
−1.17E−01
−1.21E−02
−1.85E−01
−3.50E−01

A6
7.72E−02
−7.28E−02
2.33E−01
2.71E−01
5.62E−01
1.87E+00
2.13E+00

A8
−6.68E−01
1.93E+00
−2.17E+00
−1.54E+00
−7.61E+00
−9.97E+00
−7.82E+00

A10
3.77E+00
−1.25E+01
1.49E+01
8.16E+00
4.34E+01
3.14E+01
1.75E+01

A12
−1.28E+01
4.77E+01
−6.11E+01
−2.87E+01
−1.51E+02
−6.48E+01
−2.25E+01

A14

2.61E+0I
−1.14E+02
1.48E+02
6.11E+01
3.29E+02
8.86E+01
1.33E+01

A16
−3.13E+01
1.66E+02
−2.15E+02
−7.98E+01
−4.38E+02
−7.91E+01
1.14E+00

A18
2.00E+01
−1.32E+02
1.71E+02
5.82E+01
3.22E+02
4.22E+01
−5.10E+00

A20
−5.14E+00
4.41E+01
−5.81E+01
−1.76E+01
−9.93E+01
−1.01E+01
1.67E+00

Surface

Number
S8
S9
S10
S11
S12
S13
S14

K
9.15E+01
−6.06E+01
−3.50E+01
−2.82E+01
−6.39E+00
−7.81E+00
−6.36E+00

A4
−2.48E−01
1.69E−02
−1.39E−02
−8.09E−02
−8.45E−02
−1.32E−01
−1.21E−01

A6
8.77E−02
−5.51E−01
−4.65E−01
−8.60E−02
2.83E−01
2.16E−02
6.23E−02

A8
8.22E−01
1.98E+00
1.88E+00
7.15E−01
−4.38E−01
3.30E−02
−1.70E−02

A10
−3.93E+00
−4.39E+00
−4.06E+00
−1.66E+00
5.12E−01
−1.03E−02
−1.17E−03

A12
8.12E+00
5.16E+00
5.05E+00
1.94E+00
−4.27E−01
−2.80E−03
2.49E−03

A14
−9.10E+00
−2.66E+00
−3.75E+00
−1.31E+00
2.30E−01
2.13E−03
−8.35E−04

A16
5.88E+00
−2.35E−01
1.64E+00
5.17E−01
−7.35E−02
−4.84E−04
1.38E−04

A18
−2.08E+00
8.05E−01
−3.88E−01
−1.11E−01
1.27E−02
5.10E−05
−1.15E−05

A20
3.10E−01
−2.32E−01
3.85E−02
9.89E−03
−9.14E−04
−2.13E−06
3.85E−07

FIG. 6b illustrates a longitudinal spherical aberration curve, an astigmatic field curve, and a distortion curve of the optical system of FIG. 6a. According to the longitudinal spherical aberration curves illustrated in FIG. 6b, the longitudinal spherical aberration of the optical system for light rays with wavelengths of 470.0000 nm, 510.0000 nm, 587.5618 nm, 610.0000 nm, and 650.0000 nm is ranged from −0.01 mm to 0.01 mm. According to the astigmatic field curves illustrated in FIG. 6b, the astigmatism of the optical system for a light ray with the wavelength of 587.5618 nm in the tangential and sagittal directions is ranged from −0.06 mm to 0.01 mm. According to the distortion curves illustrated in FIG. 6b, the distortion of the optical system for the light ray with the wavelength of 587.5618 nm is ranged from 0.0% and 2.0%. As illustrated in FIG. 6b, the optical system of FIG. 6a can achieve good imaging quality.

Referring to FIG. 7a and FIG. 7b, the optical system in this implementation includes the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6, and the seventh lens L7 which are sequentially arranged from the object side to the image side along the optical axis of the optical system.

The first lens L1 has a positive refractive power. The object-side surface S1 of the first lens L1 is convex near the optical axis and is convex at a circumference. The image-side surface S2 of the first lens L1 is convex near the optical axis and is convex at a circumference.

The second lens L2 has a negative refractive power. The object-side surface S3 of the second lens L2 is concave near the optical axis and is concave at a circumference. The image-side surface S4 of the second lens L2 is convex near the optical axis and is convex at a circumference.

The fourth lens L4 has a positive refractive power. The object-side surface S7 of the fourth lens L4 is concave near the optical axis and is convex at a circumference. The image-side surface S8 of the fourth lens L4 is convex near the optical axis and is convex at a circumference.

The fifth lens L5 has a positive refractive power. The object-side surface S9 of the fifth lens L5 is convex near the optical axis and is concave at a circumference. The image-side surface S10 of the fifth lens L5 is convex near the optical axis and is convex at a circumference.

The other structures of the optical system of FIG. 7a are identical with the optical system of FIG. 1a, reference can be made to the optical system of FIG. 1a.

Table 7a illustrates characteristics of the optical system in this implementation. Each of Y radius, thickness, and focal length is in units of millimeter (mm).

TABLE 7a

Optical system of FIG. 7a

f = 3.95 mm, FNO = 1.90, FOV = 82.80°

Surface
Surface

Refractive
Abbe
Focal

Number
Name
Shape
Y Radius
Thickness
Material
Index
Number
length

Object

Spherical
Infinity
Infinity

number

STO

Spherical
Infinity
−0.116

S1
First lens
Aspherical
3.521
0.781
Plastic
1.54
56.1
5.16

S2

Aspherical
−12.807
0.100

S3
Second lens
Aspherical
−5.799
0.310
Plastic
1.67
19.2
−11.77

S4

Aspherical
−22.234
0.131

S5
Third lens
Aspherical
2.698
0.420
Plastic
1.67
19.2
34.44

S6

Aspherical
2.864
0.411

S7
Fourth lens
Aspherical
−19.988
0.750
Plastic
1.54
56.1
109.02

S8

Aspherical
−15.148
0.100

S9
Fifth lens
Aspherical
27.844
0.410
Plastic
1.67
19.2
21.46

S10

Aspherical
−29.674
0.100

S11
Sixth lens
Aspherical
2.947
0.600
Plastic
1.54
56.1
3.90

S12

Aspherical
−7.027
0.150

S13
Seventh lens
Aspherical
2.124
0.420
Plastic
1.53
55.8
−3.38

S14

Aspherical
0.909
0.706

S15
Infrared cut-
Spherical
Infinity
0.210
Glass
1.52
64.2

S16
off filter
Spherical
Infinity
0.372

S17

Spherical
Infinity
0.000

Note:

The reference wavelength is 587.5618 nm

Each parameter in Table 7a represents the same meaning as that in the optical system of FIG. 1a.

Table 7b shows higher-order coefficients that can be used for each aspherical lens surface of the optical system of FIG. 7a, where a shape of each aspherical lens surface can be defined by the formula given in the optical system of FIG. 1a.

TABLE 7b

Optical system of FIG. 7a

Aspherical coefficients

Surface

Number
S1
S2
S3
S4
S5
S6
S7

K
−4.04E+00
9.87E+01
−3.98E+01
9.90E+01
−3.73E+01
−1.42E+01
−9.90E+01

A4
−5.38E−03
−3.18E−02
−1.25E−02
−7.18E−02
6.65E−02
6.97E−03
−8.60E−02

A6
−5.25E−03
4.47E−03
6.90E−02
1.65E−01
−2.79E−01
7.50E−03
1.36E−01

A8
−3.03E−02
−1.82E−02
−3.11E−01
−3.67E−01
4.43E−01
−1.19E−01
−1.08E−01

A10
1.18E−01
−9.44E−02
7.09E−01
5.85E−01
−5.45E−01
2.12E−01
1.93E−02

A12
−2.53E−01
4.31E−01
−9.52E−01
−6.11E−01
4.85E−01
−2.12E−01
5.53E−02

A14
3.06E−01
−7.12E−01
7.81E−01
4.08E−01
−2.85E−01
1.32E−01
−6.29E−02

A16
−2.10E−01
5.76E−01
−4.06E−01
−1.73E−01
1.03E−01
−5.07E−02
2.99E−02

A18
7.37E−02
−2.30E−01
1.28E−01
4.36E−02
−2.06E−02
1.10E−02
−6.69E−03

A20
−9.77E−03
3.65E−02
−1.87E−02
−4.98E−03
1.71E−03
−1.04E−03
5.73E−04

Surface

Number
S8
S9
S10
S11
S12
S13
S14

K
7.05E+01
9.90E+01
5.27E+01
−6.30E+00
−8.89E+01
−1.21E+01
−3.13E+00

A4
−4.24E−01
−1.65E−01
8.39E−02
−2.93E−02
−5.60E−02
−1.83E−01
−1.10E−01

A6
7.71E−01
5.52E−01
1.16E−01
9.01E−02
1.27E−01
1.42E−01
6.54E−02

A8
−9.56E−01
−8.10E−01
−2.85E−01
−1.04E−01
−7.97E−02
−7.31E−02
−2.69E−02

A10
7.51E−01
6.63E−01
2.40E−01
6.37E−02
2.40E−02
2.45E−02
7.31E−03

A12
−3.66E−01
−3.34E−01
−1.11E−01
−2.60E−02
−3.81E−03
−5.22E−03
−1.30E−03

A14
1.07E−01
1.06E−01
3.07E−02
7.18E−03
2.76E−04
7.03E−04
1.48E−04

A16
−1.77E−02
−2.06E−02
−5.05E−03
−1.27E−03
4.28E−08
−5.81E−05
−1.04E−05

A18
1.41E−03
2.30E−03
4.56E−04
1.29E−04
−1.09E−06
2.70E−06
4.08E−07

A20
−3.67E−05
−1.15E−04
−1.72E−05
−5.67E−06
3.95E−08
−5.41E−08
−6.88E−09

FIG. 7b illustrates a longitudinal spherical aberration curve, an astigmatic field curve, and a distortion curve of the optical system of FIG. 7a. According to the longitudinal spherical aberration curves illustrated in FIG. 7b, the longitudinal spherical aberration of the optical system for light rays with wavelengths of 470.0000 nm, 510.0000 nm, 587.5618 nm, 610.0000 nm, and 650.0000 nm is ranged from −0.04 mm to 0.02 mm. According to the astigmatic field curves illustrated in FIG. 7b, the astigmatism of the optical system for a light ray with the wavelength of 587.5618 nm in the tangential and sagittal directions is ranged from −0.01 mm to 0.03 mm. According to the distortion curves illustrated in FIG. 7b, the distortion of the optical system for the light ray with the wavelength of 587.5618 nm is ranged from 0.0% and 2.0%. As illustrated in FIG. 7b, the optical system of FIG. 7a can achieve good imaging quality.

Table 8 shows values of (Y72*TL)/(ET7*f), TL/EPD, (|AL1S1|+|AL2S1|)/f, MVd/f, ET1/(CT1*f), ET7/(CT7*f), EPD/f, (MIN6*MAX7)/(MAX6*MIN7), (CT5+CT7)/CT6, TL/ImgH of the optical system according to the first to seventh implementations.

TABLE 8

(|AL1S1| +

ET1/

(Y72*TL)/(ET7*f)
TL/EPD
|AL2S1|)/f
MVd/f
(CT1*f)

First
7.437
2.746
9.754
13.991
0.188

implementation

Second
9.036
2.742
18.909
12.606
0.184

implementation

Third
4.984
2.143
18.205
13.462
0.132

implementation

Fourth
7.328
2.244
13.359
13.037
0.143

implementation

Fifth
6.711
2.924
12.886
12.114
0.153

implementation

Sixth
6.741
2.725
15.671
16.05
0.211

implementation

Seventh
6.753
2.876
10.886
12.532
0.152

implementation

(MIN6*MAX7)/
(CT5 +
TL/

ET7/(CT7*f)
EPD/f
(MAX6* MIN7)
CT7)/CT6
ImgH

First
0.470
0.505
0.204
0.903
1.36

implementation

Second
0.374
0.495
0.207
1.323
1.324

implementation

Third
0.528
0.633
0.261
1.068
1.581

implementation

Fourth
0.416
0.606
0.223
1.092
1.475

implementation

Fifth
0.324
0.513
0.364
1.812
1.734

implementation

Sixth
0.495
0.5
0.15
0.925
1.491

implementation

Seventh
0.457
0.526
0.254
1.384
1.692

implementation

As illustrated in Table 8, each implementation of the disclosure satisfies the following expressions. 4≤(Y72*TL)/(ET7*f)≤10, 2≤TL/EPD≤3, 9≤(|AL1S1|+|AL2S1|)/f≤20, 10≤MVd/f≤20, 0≤ET1/(CT1*f)≤1 mm⁻¹, 0≤ET7/(CT7*f)≤1 mm⁻¹, 0≤EPD/f≤1, 0≤(MIN6*MAX7)/(MAX6*MIN7)≤1, 0≤(CT5+CT7)/CT6≤2, 1≤TL/ImgH≤2.

Various technical features of the above implementations can be combined arbitrarily. For the sake of convenience, not all possible combinations of the various technical features in the above implementations are described. However, as long as there is no contradiction in the combinations of these technical features, it should be considered to fall within the scope of the present disclosure.

While the present disclosure has been described specifically and in detail above with reference to several implementations, the scope of the present disclosure is not limited thereto. As will occur to those skilled in the art, the present disclosure is susceptible to various modifications and changes without departing from the spirit and principle of the present disclosure. Therefore, the scope of the present disclosure should be determined by the scope of the claims.

	Number	Date	Country
Parent	PCT/CN2020/123364	Oct 2020	US
Child	17354462		US

OPTICAL SYSTEM, LENS MODULE, AND ELECTRONIC DEVICE

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Abstract

Description

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CROSS-REFERENCE TO RELATED APPLICATIONS

Continuation in Parts (1)