CN113985581B - Optical system, camera module, electronic equipment and vehicle system - Google Patents

Abstract

The invention relates to an optical system, a camera module, electronic equipment and a vehicle-mounted system. The optical system comprises in turn from the object side to the image side along the optical axis: a first lens with negative refractive power, the object side is convex, and the image side is concave; a second lens with negative refractive power, and the object side and the image At least one of the sides is an aspheric surface; a third lens with positive refractive power, and its object side and image side are convex; a diaphragm; a fourth lens with positive refractive power, its object side and image side are convex; The fifth lens with negative refractive power has a concave surface on the object side and the convex surface on the image side; the sixth lens with positive refractive power has convex surfaces on both the object side and the image side; and the optical system satisfies the conditional formula: 60.00deg/mm<FOV/AT2<105.00 deg/mm. The above design is beneficial to the wide-angle development of the optical system.

Description

Optical systems, camera modules, electronic equipment and vehicle systems

Technical Field

The present invention relates to the field of photographic imaging technology, and in particular to an optical system, a camera module, an electronic device and a vehicle-mounted system.

Background Art

In recent years, as the country's requirements for road traffic safety and automobile safety continue to increase, the application of ADAS (Advanced Driver Assistant System), DMS (Driver Monitor System) and CMS (Crush Monitor System) in vehicle driving has been gradually promoted. Vision-based ADAS, DMS, CMS and other systems have begun to become functional options for new cars launched by automobile manufacturers, used to monitor and identify the status inside and outside the cockpit, so as to comprehensively judge the changes in the driver's driving environment, and then issue safety warnings to remind the driver of changes in driving status and achieve safe driving goals.

Among them, the application of ADAS, DMS, CMS and other systems cannot be separated from visual technology, and the use of optical systems to photograph and image the inside and outside of the cockpit is the basis of visual technology. The images captured by the optical system are also an important basis for ADAS, DMS, CMS and other systems to make control decisions. Therefore, how to improve the photographic imaging performance of the optical system has become one of the key issues in current research. However, the field of view of the optical system currently used in the vehicle-mounted system is small, resulting in a small shooting range of the optical system, which makes the captured images insufficient for the environment inside and outside the cockpit, and cannot accurately grasp the situation inside and outside the cockpit.

Summary of the invention

Based on this, it is necessary to provide an optical system, a camera module, an electronic device and a vehicle-mounted system to address the problem of small shooting range.

An optical system, comprising, in order from the object side to the image side along the optical axis:

A first lens having negative refractive power, wherein the object side surface of the first lens is convex at the near optical axis, and the image side surface of the first lens is concave at the near optical axis;

a second lens having negative refractive power, wherein the object side surface of the second lens is convex at the near optical axis, and the image side surface of the second lens is concave at the near optical axis;

a third lens having positive refractive power, wherein the object side surface of the third lens is convex at a position close to the optical axis;

a fourth lens element having positive refractive power, wherein both the object-side surface and the image-side surface of the fourth lens element are convex surfaces at a position close to the optical axis;

a fifth lens element having negative refractive power, wherein the object side surface of the fifth lens element is concave at the near optical axis, and the image side surface of the fifth lens element is convex at the near optical axis;

a sixth lens having positive refractive power, wherein both the object side surface and the image side surface of the sixth lens are convex surfaces near the optical axis; and an aperture stop is arranged between the third lens and the fourth lens;

In the above optical system, setting the object side surface of the first lens with negative refractive power as a convex surface is conducive to increasing the angle at which light is incident on the first lens, thereby improving the field of view of the optical system and effectively increasing the shooting range of the optical system, thereby achieving the design requirement of wide-angle shooting; setting the second lens with negative refractive power is conducive to correcting the spherical aberration of the optical system to improve the imaging quality; setting the third lens with positive refractive power is conducive to making the light passing through the first lens and the second lens in sequence converge smoothly to the third lens, so that the third lens can fully receive the light incident on its object side surface; in addition, setting the object side surface of the third lens as a convex surface can make the light transmitted outward from the third lens fully incident on the aperture stop, which is conducive to ensuring the optical system The optical system has the optical characteristic of a large image surface; the fourth lens with positive refractive power and the fifth lens with negative refractive power are arranged in combination, which can effectively reduce the chromatic aberration of the optical system, which is beneficial to improving the imaging quality; the object side surface and the image side surface of the sixth lens with positive refractive power are set as convex surfaces, so that the light passing through the sixth lens is better incident on the imaging surface, effectively ensuring that the optical system has sufficient relative illumination, so that the optical system can obtain a bright and clear image; and, the aperture is arranged between the third lens and the fourth lens, so that the position of the aperture is arranged close to the middle position of the optical system (that is, a central aperture is realized), so that the structure of the optical system has a certain symmetry, which can better control the optical distortion of the optical system, which is beneficial to improving the imaging quality.

And the optical system satisfies the conditional formula:

60.00deg/mm＜FOV/AT2＜105.00deg/mm; wherein FOV is the maximum field of view of the optical system, and AT2 is the distance between the image side surface of the second lens and the object side surface of the third lens on the optical axis.

When the above conditional formula is met, by controlling the distance between the image side of the second lens and the object side of the third lens on the optical axis, a sufficiently large field of view can be provided for the optical system, so that the shooting range is wider, the framing area of the shooting picture is effectively increased, and it is conducive to the development of the optical system in the direction of wide-angle. When FOV/AT2≤60.00deg/mm, it is easy to make the maximum field of view of the optical system too small, which cannot meet the shooting range required by the optical system, reduces the framing area, and cannot meet the needs of wide-angle shooting; when FOV/AT2≥105.00deg/mm, the distance between the image side of the second lens and the object side of the third lens on the optical axis is too small, resulting in the optical system being too sensitive, increasing the difficulty of assembling the optical system, and being unfavorable to the productization of the optical system.

In one of the embodiments, the fourth lens is glued to the fifth lens; through this arrangement, the positive refractive power of the fourth lens and the negative refractive power of the fifth lens can better cooperate with each other, further helping the optical system to eliminate chromatic aberration, thereby improving the imaging resolution of the optical system and better improving the imaging quality.

In one embodiment, the optical system satisfies the condition:

1.50＜f456/f＜2.50;

Among them, f is the effective focal length of the optical system, f456 is the combined focal length of the fourth lens, the fifth lens and the sixth lens, and here, the fourth lens, the fifth lens and the sixth lens together constitute a rear lens group, which is located behind the aperture.

When the above conditional formula is met, by controlling the ratio between the combined focal length of the rear lens group and the effective focal length of the optical system, it is beneficial to control the light emitted from the aperture to be smoothly transmitted from the rear lens group to the imaging surface, and the incident angle of the light incident on the imaging surface can be reasonably controlled, so as to better increase the image height of the image taken by the optical system, effectively ensure that the optical system has a suitable image plane size, and help the imaging surface of the optical system to better match the image sensor to improve the imaging quality; at the same time, it is beneficial to reasonably distribute the refractive power of each lens in the rear lens group, correct the aberration of the optical system, improve the resolution of the optical system for the image, and ensure the imaging quality.

In one embodiment, the optical system satisfies the condition:

7.00＜SDs1/Sags1＜13.00;

Among them, SDs1 is half of the maximum effective aperture of the object side of the first lens, and Sags1 is the sagittal height of the object side of the first lens at the maximum effective aperture (that is, the distance from the intersection of the object side of the first lens and the optical axis to the maximum effective aperture of its object side in the direction of the optical axis).

When the above conditional expression is met, by controlling the ratio of half of the maximum effective aperture of the object side surface of the first lens to the sagittal height of the object side surface thereof, the curvature of the first lens can be reasonably controlled, so that the light is incident on the first lens at a large angle at the object side surface of the first lens, thereby better providing the optical system with a larger field of view to achieve wide-angle, and at the same time reducing the risk of ghost images when the optical system is shooting, so that the imaging quality of the optical system is higher, and in addition, it is also conducive to reducing the difficulty of molding the first lens, so that the optical system can be better commercialized.

In one embodiment, the optical system satisfies the condition:

1.20＜CT4/AT3＜2.00;

Wherein, CT4 is the thickness of the fourth lens on the optical axis, and AT3 is the distance between the image side surface of the third lens and the object side surface of the fourth lens on the optical axis.

When the above conditional expression is satisfied, by controlling the ratio between the thickness of the fourth lens on the optical axis and the distance between the image side surface of the third lens and the object side surface of the fourth lens on the optical axis, the thickness of the fourth lens on the optical axis and the curvature of the object side surface of the fourth lens can be reasonably configured to be controlled within a reasonable range, which is conducive to reducing the manufacturing difficulty of the fourth lens, thereby reducing the production cost.

In one embodiment, the optical system satisfies the condition:

2.00＜|Rs12/Sags12|＜5.00;

Wherein, Rs12 is the curvature radius of the image side surface of the sixth lens at the optical axis, and Sags12 is the sag height of the image side surface of the sixth lens at the maximum effective aperture.

When the above conditional expression is satisfied, the refractive power of the sixth lens can be controlled within a reasonable range by controlling the ratio between the radius of curvature of the image side surface of the sixth lens at the optical axis and the sag height of the image side surface, which is beneficial for the light passing through the sixth lens to be better incident on the imaging surface. In addition, the curvature degree of the image side surface of the sixth lens can be made appropriate, which is beneficial for processing and production; when |Rs12/Sags12|≤2.00, the sag height value is too large or the image side surface is too curved, which increases the difficulty of lens manufacturing; |Rs12/Sags12|≥5.00, the radius of curvature of the image side surface of the sixth lens at the optical axis is too large, causing the effective focal length of the sixth lens to decrease, which is not beneficial for the sixth lens to provide a higher refractive power.

In one embodiment, the optical system satisfies the condition:

13.00＜|DIS/FNO|＜19.00;

Wherein, DIS is the maximum distortion value of the optical system, and FNO is the aperture number of the optical system.

Since the aperture number = effective focal length of the optical system / aperture of the diaphragm, that is, the aperture number is inversely proportional to the aperture of the diaphragm, and the aperture of the diaphragm affects the size of the field of view of the optical system, when the above conditional formula is met, by controlling the maximum distortion value and aperture number of the optical system within a reasonable range, while ensuring that the optical distortion is well controlled, it is possible to ensure that the aperture has a sufficiently large aperture, thereby effectively ensuring the field of view of the optical system. In addition, a sufficiently large aperture is conducive to the optical system obtaining sufficient light input, so that it can also have good imaging quality in a weak light environment. When |DIS/FNO|≤13.00, the aperture number is likely to be too large, which is not conducive to increasing the aperture of the diaphragm, making it difficult to obtain a larger field of view; when |DIS/FNO|≥19.00, the maximum distortion value of the optical system is too large, which is not conducive to reasonably controlling the distortion of the optical system, and it is easy to cause the image obtained by the optical system to be distorted at the edge, reducing the imaging quality.

In one embodiment, the optical system satisfies the condition:

70.00deg＜(FOV×f)/ImgH＜90.00deg;

Wherein, f is the effective focal length of the optical system, and ImgH is half of the image height corresponding to the maximum field of view of the optical system.

When the above conditional formula is met, while realizing the optical system with a large field of view, it is also beneficial to ensure the image height of the optical system, ensure the image size of the image on the imaging surface, so that the optical system has a suitable image size, and improve the brightness of the imaging surface of the optical system. When (FOV×f)/ImgH≥90.00deg, the image height of the optical system is small, resulting in the image size being too small, and the imaging surface of the optical system is difficult to match and set with the image sensor, which greatly reduces the relative illumination of the imaging surface, and the brightness of the imaging surface is dim. The image captured is prone to vignetting, which reduces the imaging quality; when (FOV×f)/ImgH≤70.00deg, the field of view of the optical system is small, resulting in a narrow field of view range captured by the optical system, which is not conducive to achieving wide angle.

In one embodiment, the optical system satisfies the condition:

2.00＜|f2/CT2|＜3.50;

Wherein, f2 is the effective focal length of the second lens, and CT2 is the thickness of the second lens on the optical axis.

When the above conditional expression is met, by reasonably configuring the effective focal length of the second lens and the thickness of the second lens on the optical axis, the aberration, spherical aberration, coma and other phenomena of the system can be effectively corrected, thereby improving the imaging quality. When |f2/CT2|≤2.00, the effective focal length of the second lens group is too small, resulting in an excessively strong refractive power of the second lens, which is prone to produce larger aberrations; when |f2/CT2|≥3.50, the effective focal length of the second lens group is too large, which is not conducive to the reasonable distribution of the refractive power of the second lens. Due to insufficient refractive power, high-order spherical aberration, coma and other phenomena are easily produced at the second lens, thereby affecting the imaging quality of the optical system.

A camera module comprises an image sensor and any one of the above optical systems, wherein the image sensor is arranged on the image side of the optical system. By adopting the above optical system, the camera module has a large field of view, the shooting range is expanded, and the imaging effect is good.

An electronic device comprises a fixing part and the above-mentioned camera module, wherein the camera module is arranged on the fixing part. When the electronic device is used to shoot a scene, the shooting range is wide, the imaging effect is good, and the shooting quality can be well improved.

A vehicle-mounted system includes the above-mentioned electronic device. When the electronic device is used to shoot scenes, the shooting range is wide and the imaging effect is good, and the shooting quality can be greatly improved.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of the structure of an optical system provided in a first embodiment of the present application;

FIG2 is a longitudinal spherical aberration curve diagram of the optical system in the first embodiment;

FIG3 includes an astigmatism curve diagram and a distortion curve diagram of the optical system in the first embodiment;

FIG4 is a schematic diagram of the structure of an optical system provided in a second embodiment of the present application;

FIG5 is a graph showing the longitudinal spherical aberration of the optical system in the second embodiment;

FIG6 includes an astigmatism curve diagram and a distortion curve diagram of the optical system in the second embodiment;

FIG7 is a schematic diagram of the structure of an optical system provided in a third embodiment of the present application;

FIG8 is a graph showing the longitudinal spherical aberration of the optical system in the third embodiment;

FIG9 includes an astigmatism curve diagram and a distortion curve diagram of the optical system in the third embodiment;

FIG10 is a schematic structural diagram of an optical system provided in a fourth embodiment of the present application;

FIG11 is a graph showing the longitudinal spherical aberration of the optical system in the fourth embodiment;

FIG12 includes astigmatism curves and distortion curves of the optical system in the fourth embodiment;

FIG13 is a schematic structural diagram of an optical system provided in a fifth embodiment of the present application;

FIG14 is a graph showing the longitudinal spherical aberration of the optical system in the fifth embodiment;

FIG15 includes astigmatism curves and distortion curves of the optical system in the fifth embodiment;

FIG16 is a schematic diagram of the structure of a camera module provided in one embodiment of the present application;

FIG. 17 is a schematic diagram of the structure of an electronic device provided in one embodiment of the present application.

DETAILED DESCRIPTION

In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific embodiments disclosed below.

In the description of the present invention, it is necessary to understand that the terms "center", "longitudinal", "lateral", "length", "thickness", "top", "front", "rear", "axial", "radial" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element at the same time.

1 , in an embodiment of the present application, the optical system 10 includes a first lens L1, a second lens L2, a third lens L3, a stop STO, a fourth lens L4, a fifth lens L5, and a sixth lens L6 in sequence from the object side to the image side along the optical axis 101. The lenses in the optical system 10 are coaxially arranged, that is, the optical axes of the lenses are all located on the same straight line, and the straight line can be used as the optical axis 101 of the optical system 10. The lenses in the optical system 10 are installed in a lens barrel to assemble into a camera lens.

Among them, the first lens L1 has negative refractive power, the second lens L2 has negative refractive power, the third lens L3 has positive refractive power, the fourth lens L4 has positive refractive power, the fifth lens L5 has negative refractive power, and the sixth lens L6 has positive refractive power.

The first lens L1 has an object-side surface S1 and an image-side surface S2, the second lens L2 has an object-side surface S3 and an image-side surface S4, the third lens L3 has an object-side surface S5 and an image-side surface S6, the fourth lens L4 has an object-side surface S7 and an image-side surface S8, the fifth lens L5 has an object-side surface S9 and an image-side surface S10, and the sixth lens L6 has an object-side surface S11 and an image-side surface S12. The optical system 10 also has an imaging surface Si, which is located on the image side of the sixth lens L6. Light from an object on the object plane of the optical system 10 can be converged on the imaging surface Si after being adjusted by each lens of the optical system 10. Generally, the imaging surface Si of the optical system 10 coincides with the photosensitive surface of the image sensor.

In the embodiment of the present application, the object-side surface S1 of the first lens L1 is convex at the near optical axis, and the image-side surface S2 is concave at the near optical axis; the object-side surface S3 of the second lens L2 is convex at the near optical axis, and the image-side surface S4 is concave at the near optical axis; the object-side surface S5 of the third lens L3 is convex at the near optical axis; the object-side surface S7 and the image-side surface S8 of the fourth lens L4 are both convex at the near optical axis; the object-side surface S9 of the fifth lens L5 is concave at the near optical axis, and the image-side surface S10 is convex at the near optical axis; the object-side surface S11 and the image-side surface S12 of the sixth lens L6 are both convex at the near optical axis; and the image-side surface S6 of the third lens L3 can be either convex or concave at the optical axis.

Among them, the first lens L1, the second lens L2 and the fifth lens L5 are all meniscus lens structures, and the third lens L3, the fourth lens L4 and the sixth lens L6 are all biconvex lens structures. It should be noted that when describing that the lens surface has a certain surface shape near the optical axis, that is, the lens surface has this surface shape near the optical axis 101, and the lens surface can have the same surface shape or the opposite surface shape in the area near the maximum effective aperture.

Through the above lens design, in the above optical system 10, the object side surface S1 of the first lens L1 with negative refractive power is set as a convex surface, which is conducive to increasing the angle of light incident on the first lens L1, thereby improving the field of view of the optical system 10, effectively increasing the shooting range of the optical system 10, and realizing the design requirement of wide-angle shooting; the second lens L2 with negative refractive power is set, which is conducive to correcting the spherical aberration of the optical system 10 to improve the imaging quality; the third lens L3 is set to have a positive refractive power, which is conducive to making the light passing through the first lens L1 and the second lens L2 in sequence converge smoothly to the third lens L3, so that the third lens L3 can fully receive the light incident on its object side surface. In addition, the object side surface S5 of the third lens L3 is set as a convex surface, so that the light transmitted outward from the third lens L3 can be fully incident on the aperture STO, which is conducive to ensuring the optical characteristics of the large image surface of the optical system 10; The fourth lens L4 with a negative refractive power and the fifth lens L5 with a negative refractive power are arranged in coordination, which can effectively reduce the chromatic aberration of the optical system 10 and is beneficial to improving the imaging quality. In addition, when the vehicle is in a dark driving environment such as an underground parking lot and a tunnel, the illumination of the image taken by the optical system is low, resulting in the captured image being dim and blurred, making it impossible for ADAS, DMS, CMS and other systems to accurately identify the current environment inside and outside the vehicle's cockpit based on the image, resulting in ADAS, DMS, CMS being prone to misjudgment and wrong judgment. Here, by setting the object side surface S11 and the image side surface S12 of the sixth lens L6 with a positive refractive power to be convex surfaces, the light passing through the sixth lens L6 is better incident on the imaging surface Si, effectively ensuring that the optical system 10 has sufficient relative illumination, so that the optical system 10 can obtain a bright and clear image, effectively solving the problem caused by insufficient illumination of the captured image.

In an embodiment of the present application, a stop STO is provided between the third lens L3 and the fourth lens L4. The stop STO is an aperture stop, which is used to limit the amount of light entering the system, and at the same time can also achieve a certain degree of suppression of aberrations and stray light. The stop can be a single light-blocking member assembled between the lenses, or can also be formed by a clamping member of a fixed lens. In some embodiments, the stop STO during the zooming process is located on the object side and remains fixed relative to the imaging surface Si of the system.

In the above-mentioned optical system 10, since the aperture STO is arranged between the third lens L3 and the fourth lens L4, the aperture STO is arranged between the third lens L3 and the fourth lens L4 so that the position of the aperture STO is close to the middle position of the optical system 10 (that is, the central aperture STO is realized), so that the structure of the optical system 10 has a certain symmetry, which can better control the optical distortion of the optical system 10, and is conducive to improving the imaging quality.

In one embodiment, the fourth lens L4 is cemented with the fifth lens L5. Through this arrangement, the positive refractive power of the fourth lens L4 and the negative refractive power of the fifth lens L5 can better cooperate with each other, further helping the optical system 10 to eliminate chromatic aberration, thereby improving the imaging resolution of the optical system 10 and better improving the imaging quality.

And the optical system 10 satisfies the conditional expression:

60.00 deg/mm＜FOV/AT2＜105.00 deg/mm; wherein FOV is the maximum field angle of the optical system 10, and AT2 is the distance between the image-side surface S4 of the second lens L2 and the object-side surface S5 of the third lens L3 on the optical axis 101. In some embodiments, the above values include but are not limited to: 65.482 deg/mm, 69.127 deg/mm, 73.683 deg/mm, 76.335 deg/mm, 80.883 deg/mm, 84.970 deg/mm, 88.270 deg/mm, 94.715 deg/mm, 99.715 deg/mm or 102.00 deg/mm.

When the above conditional expression is satisfied, by controlling the distance between the image side surface S4 of the second lens L2 and the object side surface S5 of the third lens L3 on the optical axis 101, a sufficiently large field of view angle can be provided for the optical system 10, so that the shooting range is wider, the framing area of the shooting picture is effectively increased, and it is beneficial for the optical system 10 to develop in the direction of wide angle. When FOV/AT2≤60.00deg/mm, it is easy to make the maximum field of view angle of the optical system 10 too small, which cannot meet the shooting range required by the optical system 10, reduces the framing area, and cannot meet the demand for wide-angle shooting; when FOV/AT2≥105.00deg/mm, the distance between the image side surface S4 of the second lens L2 and the object side surface S5 of the third lens L3 on the optical axis 101 is too small, making the optical system 10 too sensitive, increasing the difficulty of assembling the optical system 10, and not conducive to the productization of the optical system 10.

1.50＜f456/f＜2.50;

Wherein, f is the effective focal length of the optical system 10, and f456 is the combined focal length of the fourth lens L4, the fifth lens L5 and the sixth lens L6. Here, the fourth lens L4, the fifth lens L5 and the sixth lens L6 together constitute a rear lens group, which is located after the aperture STO. In some embodiments, the above values include but are not limited to: 2.071, 2.079, 2.085, 2.087, 2.091, 2.094, 2.099, 2.105, 2.122, 2.148 or 2.153.

When the above conditional formula is met, by controlling the ratio between the combined focal length of the rear lens group and the effective focal length of the optical system 10, it is beneficial to control the light emitted from the aperture STO to be smoothly transmitted from the rear lens group to the imaging surface Si, and can reasonably control the incident angle of the light incident on the imaging surface Si, so as to better increase the image height of the image taken by the optical system 10, effectively ensure that the optical system 10 has a suitable image plane size, and facilitate the imaging surface Si of the optical system 10 to better match with the image sensor to improve the imaging quality; at the same time, it is beneficial to reasonably distribute the refractive power of each lens in the rear lens group, which is beneficial to correct the aberration of the optical system 10, improve the resolution of the optical system 10 for the image, and ensure the imaging quality.

7.00＜SDs1/Sags1＜13.00;

Wherein, SDs1 is half of the maximum effective aperture of the object side surface S1 of the first lens L1, and Sags1 is the sagittal height of the object side surface S1 of the first lens L1 at the maximum effective aperture (i.e., the distance from the intersection of the object side surface of the first lens and the optical axis to the maximum effective aperture of the object side surface in the direction of the optical axis). In some embodiments, the above values include but are not limited to: 8.640, 8.951, 9.370, 9.667, 9.880, 10.300, 10.543, 10.921, 11.036 or 11.130.

When the above conditional expression is satisfied, by controlling the ratio of half of the maximum effective aperture of the object side surface S1 of the first lens L1 to the sagittal height of the object side surface thereof, the curvature of the first lens L1 can be reasonably controlled, so that light is incident on the first lens L1 at a large angle at the object side surface S1 of the first lens L1, thereby better providing the optical system 10 with a larger field of view to achieve wide angle, and at the same time reducing the risk of ghost images when the optical system 10 is photographed, so that the imaging quality of the optical system 10 is higher, and in addition, it is also conducive to reducing the difficulty of molding the first lens L1, so that the optical system 10 can be better commercialized.

1.20＜CT4/AT3＜2.00;

Wherein, CT4 is the thickness of the fourth lens L4 on the optical axis 101, and AT3 is the distance between the image-side surface S6 of the third lens L3 and the object-side surface S7 of the fourth lens L4 on the optical axis 101. In some embodiments, the above values include but are not limited to: 1.484, 1.503, 1.524, 1.533, 1.547, 1.582, 1.613, 1.646, 1.770 or 1.821.

2.00＜|Rs12/Sags12|＜5.00;

Wherein, Rs12 is the radius of curvature of the image side surface of the sixth lens L6 at the optical axis 101, and Sags12 is the sag height of the image side surface of the sixth lens L6 at the maximum effective aperture. In some embodiments, the above values include but are not limited to: 2.557, 2.587, 2.614, 2.621, 2.639, 2.654, 2.709, 2.741, 2.790 or 2.891.

When the above conditional expression is satisfied, by controlling the ratio between the radius of curvature of the image side surface of the sixth lens L6 at the optical axis 101 and the sag height of the image side surface, the refractive power of the sixth lens L6 can be controlled within a reasonable range, which is beneficial for the light passing through the sixth lens L6 to be better incident on the imaging surface Si. In addition, the curvature degree of the image side surface of the sixth lens L6 can be made appropriate, which is beneficial for processing and production. When |Rs12/Sags12|≤2.00, the sag height value is too large or the image side surface is too curved, which increases the difficulty of lens manufacturing. When |Rs12/Sags12|≥5.00, the radius of curvature of the image side surface of the sixth lens L6 at the optical axis 101 is too large, resulting in a reduction in the effective focal length of the sixth lens L6, which is not beneficial for the sixth lens L6 to provide a higher refractive power.

When the above conditional expression is satisfied, the effective focal length of the sixth lens L6 is controlled within a reasonable range, so that the sixth lens L6 contributes appropriate positive refractive power to the optical system 10, which is beneficial for light to be better incident on the imaging surface Si for imaging.

13.00＜|DIS/FNO|＜19.00;

Wherein, DIS is the maximum distortion value of the optical system 10, and FNO is the aperture number of the optical system 10. In some embodiments, the above values include but are not limited to: 14.760, 15.304, 15.932, 16.449, 16.950, 17.020, 17.160, 17.342, 17.863 or 18.030.

Since the aperture number = effective focal length of the optical system 10/the clear aperture of the aperture STO, that is, the aperture number is inversely proportional to the clear aperture of the aperture STO, and the clear aperture of the aperture STO affects the size of the field of view angle of the optical system 10, when the above conditional formula is met, by controlling the maximum distortion value and the aperture number of the optical system 10 within a reasonable range, while ensuring that the optical distortion is better controlled, it is possible to ensure that the aperture STO has a sufficiently large clear aperture, thereby effectively ensuring the field of view angle of the optical system 10. In addition, a sufficiently large clear aperture is beneficial for the optical system 10 to obtain sufficient light input, so that it can have good imaging quality even in a low-light environment. When |DIS/FNO|≤13.00, the aperture number is likely to be too large, which is not conducive to increasing the clear aperture of the aperture STO, making it difficult to obtain a larger field of view; when |DIS/FNO|≥19.00, the maximum distortion value of the optical system 10 is too large, which is not conducive to reasonably controlling the distortion of the optical system 10, and easily causes the image obtained by the optical system 10 to be distorted at the edge, thereby reducing the imaging quality.

70.00deg＜(FOV×f)/ImgH＜90.00deg;

Wherein, f is the effective focal length of the optical system 10, and ImgH is half of the image height corresponding to the maximum field angle of the optical system 10. In some embodiments, the above values include but are not limited to: 79.074deg, 80.358deg, 80.764deg, 81.149deg, 82.712deg, 82.835deg, 82.923deg, 83.117deg, 83.340deg or 83.468deg.

When the above conditional formula is satisfied, while realizing the optical system 10 with a large field of view, it is also beneficial to ensure the image height of the optical system 10, ensure the image size of the image on the imaging surface Si, so that the optical system 10 has a suitable image size, and improves the brightness of the imaging surface Si of the optical system 10. When (FOV×f)/ImgH≥90.00deg, the image height of the optical system 10 is small, resulting in an image size that is too small, and the imaging surface Si of the optical system 10 is difficult to match and set with the image sensor, so that the relative illumination of the imaging surface Si is greatly reduced, the brightness of the imaging surface Si is dim, and the image captured is prone to dark corners, which reduces the imaging quality; when (FOV×f)/ImgH≤70.00deg, the field of view of the optical system 10 is small, resulting in a reduction in the field of view range captured by the optical system 10, which is not conducive to achieving wide angle.

2.00＜|f2/CT2|＜3.50;

Wherein, f2 is the effective focal length of the second lens L2, and CT2 is the thickness of the second lens L2 on the optical axis 101. In some embodiments, the above values include but are not limited to: 2.505, 2.506, 2.578, 2.617, 2.784, 2.823, 2.968, 3.073, 3.144 or 3.218.

When the above conditional expression is satisfied, by reasonably configuring the effective focal length of the second lens L2 and the thickness of the second lens L2 on the optical axis 101, the aberration, spherical aberration, coma and other phenomena of the system can be effectively corrected, thereby improving the imaging quality. When |f2/CT2|≤2.00, the effective focal length of the second lens L2 group is too small, resulting in an excessively strong refractive power of the second lens L2, which is prone to produce larger aberrations; when |f2/CT2|≥3.50, the effective focal length of the second lens L2 group is too large, which is not conducive to the reasonable distribution of the refractive power of the second lens L2. Due to insufficient refractive power, high-order spherical aberration, coma and other phenomena are easily produced at the second lens L2, thereby affecting the imaging quality of the optical system 10.

It should be noted that the reference wavelength of the effective focal length in the above relationship conditions is 546nm, and the effective focal length at least refers to the value of the corresponding lens or lens group at the near optical axis. And the above relationship conditions and the technical effects brought about by them are for the six-piece optical system 10 with the above lens design. When the lens design (number of lenses, refractive power configuration, surface configuration, etc.) of the above optical system 10 cannot be ensured, it will be difficult to ensure that the optical system 10 can still have the corresponding technical effects when satisfying these relationships, and it may even cause a significant decline in camera performance.

In some embodiments, at least one lens in the optical system 10 has an aspheric surface type. When at least one side surface of the lens (object side or image side) is an aspheric surface, the lens can be said to have an aspheric surface type. Specifically, the object side and image side of each lens can be designed as aspheric surfaces. The aspheric surface type setting can further help the optical system 10 to more effectively eliminate aberrations and improve imaging quality. It is also beneficial to the miniaturized design of the optical system 10, so that the optical system 10 can have excellent optical effects while maintaining a miniaturized design. Of course, in other embodiments, at least one lens in the optical system 10 may have a spherical surface type. The spherical surface type design can reduce the difficulty of lens preparation and reduce preparation costs. In some embodiments, at least one lens in the optical system 10 has an aspherical surface type, and at least one lens has a spherical surface type, for example, at least one surface of the first lens L1, the third lens L3, the fourth lens L4, and the fifth lens L5 has a spherical surface type, and at least one surface of the second lens L2 and the sixth lens L6 (object side or image side) has an aspherical surface type, but the specific configuration relationship can be determined according to actual needs and is not exhaustively listed here. It should be noted that the ratio of the dimensions such as the thickness and surface curvature of each lens in the drawings may have a certain deviation.

In some embodiments, at least one lens in the optical system 10 is made of plastic (PC), and the plastic material may be polycarbonate, gum, etc. In some embodiments, at least one lens in the optical system 10 is made of glass (GL). Lenses made of plastic can reduce the production cost of the optical system 10, while lenses made of glass can withstand higher or lower temperatures and have excellent optical effects and better stability. In some embodiments, at least two lenses of different materials may be provided in the optical system 10, for example, a design combining a glass lens and a plastic lens may be adopted, but the specific configuration relationship may be determined according to actual needs, and will not be exhaustively listed here.

The optical system 10 of the present application is described below through a more specific embodiment:

First embodiment

1, in the first embodiment, the optical system 10 includes, from the object side to the image side, a first lens L1 with negative refractive power, a second lens L2 with negative refractive power, a third lens L3 with positive refractive power, an aperture STO, a fourth lens L4 with positive refractive power, a fifth lens L5 with negative refractive power, and a sixth lens L6 with positive refractive power. The surface shapes of the surfaces of the lenses in the optical system 10 are as follows:

The object-side surface S1 of the first lens L1 is convex at the near optical axis, and the image-side surface S2 is concave at the near optical axis;

The object-side surface S3 of the second lens L2 is convex at the near optical axis, and the image-side surface S4 is concave at the near optical axis;

The object-side surface S5 of the third lens L3 is convex at the near optical axis, and the image-side surface S6 is concave at the near optical axis;

The object-side surface S7 of the fourth lens L4 is convex at the near optical axis, and the image-side surface S8 is convex at the near optical axis;

The object-side surface S9 of the fifth lens L5 is concave at the near optical axis, and the image-side surface S10 is convex at the near optical axis;

The object-side surface S11 of the sixth lens L6 is convex at the near optical axis, and the image-side surface S12 is convex at the near optical axis.

In the embodiments of the present application, when it is described that the lens surface has a certain surface shape near the optical axis, it means that the lens surface has the surface shape near the optical axis 101 .

In the first embodiment, the object-side surface and the image-side surface of each lens in the first lens L1, the third lens L3, the fourth lens L4 and the fifth lens L5 are all spherical surfaces. The material of each lens in the first lens L1, the third lens L3, the fourth lens L4 and the fifth lens L5 is glass; the object-side surface and the image-side surface of each lens in the second lens L2 and the sixth lens L6 are all aspherical surfaces, and the material of each lens in the second lens L2 and the sixth lens L6 is plastic.

In particular, the combined lens formed by the fourth lens L4 and the fifth lens L5 is arranged as a cemented lens, that is, the fourth lens L4 and the fifth lens L5 are cemented to form the combined lens. This arrangement is conducive to the molding of the combined lens. In addition, the positive refractive power of the fourth lens L4 and the negative refractive power of the fifth lens L5 can better cooperate with each other, further helping the optical system to eliminate chromatic aberration, thereby improving the imaging resolution of the optical system and better improving the imaging quality.

The lens parameters of the optical system 10 in this embodiment are shown in the following Table 1. The elements from the object side to the image side of the optical system 10 are arranged in order from top to bottom according to Table 1, where STO represents the aperture.

The filter 110 is a double-pass filter, which is used to pass visible light or infrared light; the filter 110 can be a part of the optical system 10, and can also be removed from the optical system 10, but when the filter 110 is removed, the total optical length of the optical system 110 remains unchanged.

It should be noted that, in actual application, the infrared light channel and the visible light channel can be set according to the lighting conditions of the environment. When the lighting conditions are brighter (for example, during the day or in other environments with strong light intensity), the visible light channel is used in combination with the optical system 10. The visible light channel can pass visible light to ensure that the optical system 10 can obtain images with better imaging quality under brighter lighting conditions; when the lighting conditions are darker (for example, at night, in underground parking lots, tunnels and other dark lighting environments, or in other environments with weak light intensity), the infrared light channel is used in combination with the optical system 10. The infrared light channel can pass infrared light to ensure that the optical system 10 can obtain images with better imaging quality under dark lighting conditions.

By respectively matching the infrared light channel and the visible light channel with the optical system 10 , the optical system 10 has good imaging effects in both the visible light and infrared light bands, so that the optical system 10 has the function of being used both day and night.

The optical system 10 further includes a protective glass 120 disposed between the filter 110 and the imaging surface Si, and used for covering the image sensor to protect the image sensor.

The Y radius in Table 1 is the radius of curvature of the corresponding surface of the lens at the optical axis 101 and along the Y direction. The absolute value of the first value of the lens in the "Thickness" parameter column is the thickness of the lens on the optical axis 101, and the absolute value of the second value is the distance from the image side of the lens to the next optical element (lens or aperture) on the optical axis 101, wherein the thickness parameter of the aperture represents the distance from the aperture surface to the object side of the adjacent lens on the image side on the optical axis 101. The reference wavelength of the refractive index and Abbe number of each lens in the table is 587.6nm, the reference wavelength of the focal length (effective focal length) is 546nm, and the numerical units of the Y radius, thickness, and focal length (effective focal length) are all millimeters (mm), and the unit of the maximum field of view angle is deg. In addition, the parameter data and lens surface structure used for relationship calculation in the following embodiments shall be based on the data in the lens parameter table in the corresponding embodiment.

Table 1

As can be seen from Table 1, the effective focal length f of the optical system 10 in the first embodiment is 1.86 mm, the aperture number FNO is 2.4, and the maximum field of view FOV is 143.6°. The optical system 10 has a large field of view, and the image size of the image captured is large, and has the characteristics of wide angle and large image surface, and the image quality is good. When the image sensor is assembled, FOV can also be understood as the maximum field of view of the optical system 10 in the diagonal direction of the rectangular effective pixel area corresponding to the image sensor.

The following Table 2 shows the aspheric coefficients of the corresponding lens surfaces in Table 1, where k is the cone coefficient and Ai is the coefficient corresponding to the i-th order high-order term in the aspheric surface shape formula.

Table 2

Surface number S3 S4 S11 S12 k -5.643E+00 -6.229E-01 2.160E+01 -2.856E+00 A4 1.077E-02 1.886E-02 -4.602E-03 -5.660E-03 A6 -1.506E-03 -1.534E-02 1.503E-03 1.074E-03 A8 2.296E-04 1.488E-02 -1.690E-03 -4.632E-05 A10 -6.257E-05 -1.448E-02 1.029E-03 -2.031E-04 A12 1.635E-05 5.186E-03 -4.093E-04 1.181E-04 A14 -3.232E-06 -2.800E-03 1.057E-04 -3.417E-05 A16 4.089E-07 5.808E-04 -1.683E-05 5.656E-06 A18 -2.844E-08 -6.824E-05 5.473E-06 -5.074E-07 A20 8.188E-10 3.534E-06 -5.362E-08 5.907E-08

The calculation of the aspheric surface can refer to the aspheric surface formula:

Wherein, Z is the sagittal height of the corresponding position of the lens surface, r is the distance from the corresponding position of the lens surface to the optical axis, c is the curvature of the lens surface at the optical axis 101, k is the cone coefficient, and Ai is the coefficient corresponding to the i-th order high-order term. It should be noted that the actual surface shape of the lens is not limited to the shape shown in the drawings, and the drawings are not drawn strictly to scale, and there may be some differences between them and the actual surface structure of the lens.

In the first embodiment, the optical system 10 satisfies the following relationships:

FIG2 includes a longitudinal spherical aberration curve diagram (Longitudinal Spherical Aberration) of the optical system 10 in the first embodiment, which shows the deviation of light of different wavelengths from the convergence focus after the lens. The ordinate of the longitudinal spherical aberration curve diagram represents the normalized pupil coordinate (Normalized Pupil Coordinator) from the center of the pupil to the edge of the pupil, and the abscissa represents the distance (in mm) from the imaging surface to the intersection of the light and the optical axis. Specifically, FIG2 (a) shows the deviation of infrared light with wavelengths of 960nm, 940nm and 920nm from the convergence focus after the lens, and FIG2 (b) shows the deviation of visible light with wavelengths of 656nm, 588nm, 546nm, 486nm and 436nm from the convergence focus after the lens. It can be seen from the longitudinal spherical aberration curve diagram that the degree of deviation of the convergence focus of each wavelength of light in the first embodiment tends to be consistent, and the diffuse spots or color halo in the imaging picture are effectively suppressed.

FIG3 includes an astigmatism curve diagram and a distortion curve diagram of the optical system 10 in the first embodiment, wherein the reference wavelength of the astigmatism curve diagram and the distortion curve diagram is 546 nm.

Astigmatic Field Curves, where the horizontal axis along the X-axis represents the focus offset (in mm), the vertical axis along the Y-axis represents the image height (in mm), and the S curve in the figure represents the sagittal field curvature at 546nm, and the T curve represents the meridian field curvature at 546nm. It can be seen from the figure that the field curvature of the optical system is small, the degree of image curvature is effectively suppressed, and the difference between the sagittal field curvature and the meridian field curvature under each field of view is small, and the astigmatism of each field of view is better controlled. Therefore, it can be seen that the field center to the edge of the optical system 10 has clear imaging.

Distortion curve diagram (Distortion), wherein the horizontal axis along the X-axis direction represents the distortion, and the vertical axis along the Y-axis direction represents the image height (in mm). The distortion curve diagram represents the distortion magnitude values corresponding to different image height positions, and the distortion degree of the optical system 10 is well controlled.

Second embodiment

4 , in the second embodiment, the optical system 10 includes, from the object side to the image side, a first lens L1 having negative refractive power, a second lens L2 having negative refractive power, a third lens L3 having positive refractive power, a stop STO, a fourth lens L4 having positive refractive power, a fifth lens L5 having negative refractive power, and a sixth lens L6 having positive refractive power.

The surface shapes of the lens surfaces in the optical system 10 are as follows:

The object-side surface S1 of the first lens L1 is convex at the near optical axis, and the image-side surface S2 is concave at the near optical axis;

The object-side surface S3 of the second lens L2 is convex at the near optical axis, and the image-side surface S4 is concave at the near optical axis;

The object-side surface S5 of the third lens L3 is convex at the near optical axis, and the image-side surface S6 is convex at the near optical axis;

The object-side surface S7 of the fourth lens L4 is convex at the near optical axis, and the image-side surface S8 is convex at the near optical axis;

The object-side surface S9 of the fifth lens L5 is concave at the near optical axis, and the image-side surface S10 is convex at the near optical axis;

The object-side surface S11 of the sixth lens L6 is convex at the near optical axis, and the image-side surface S12 is convex at the near optical axis.

In addition, the object side surface and the image side surface of each lens in the first lens L1, the third lens L3, the fourth lens L4 and the fifth lens L5 are all spherical surfaces. The material of each lens in the first lens L1, the third lens L3, the fourth lens L4 and the fifth lens L5 is glass; the object side surface and the image side surface of each lens in the second lens L2 and the sixth lens L6 are all aspherical surfaces, and the material of each lens in the second lens L2 and the sixth lens L6 is plastic.

In particular, the combined lens formed by the fourth lens L4 and the fifth lens L5 is arranged as a cemented lens, that is, the fourth lens L4 and the fifth lens L5 are cemented to form the combined lens.

In addition, the lens parameters of the optical system 10 in the second embodiment are given in Table 3 and Table 4, wherein the definitions of the structures and parameters can be obtained from the first embodiment and are not described in detail here.

Table 3

Table 4

The optical system 10 in this embodiment satisfies the following relationship:

It can be seen from the aberration diagrams in Figures 5 and 6 that the longitudinal spherical aberration, field curvature, astigmatism, and distortion of the optical system 10 are all well controlled, wherein the focus shift corresponding to the longitudinal spherical aberration at each wavelength is small, and the meridional field curvature and sagittal field curvature at each field of view are all controlled within 0.050 mm, the image plane curvature is well suppressed, and the astigmatism and distortion are also reasonably adjusted.

Third embodiment

7 , in the third embodiment, the optical system 10 includes, from the object side to the image side, a first lens L1 having negative refractive power, a second lens L2 having negative refractive power, a third lens L3 having positive refractive power, a stop STO, a fourth lens L4 having positive refractive power, a fifth lens L5 having negative refractive power, and a sixth lens L6 having positive refractive power.

The surface shapes of the lens surfaces in the optical system 10 are as follows:

The object-side surface S1 of the first lens L1 is convex at the near optical axis, and the image-side surface S2 is concave at the near optical axis;

The object-side surface S3 of the second lens L2 is convex at the near optical axis, and the image-side surface S4 is concave at the near optical axis;

The object-side surface S5 of the third lens L3 is convex at the near optical axis, and the image-side surface S6 is concave at the near optical axis;

The object-side surface S7 of the fourth lens L4 is convex at the near optical axis, and the image-side surface S8 is convex at the near optical axis;

The object-side surface S9 of the fifth lens L5 is concave at the near optical axis, and the image-side surface S10 is convex at the near optical axis;

The object-side surface S11 of the sixth lens L6 is convex at the near optical axis, and the image-side surface S12 is convex at the near optical axis.

In addition, the object side surface and the image side surface of each lens in the first lens L1, the third lens L3, the fourth lens L4 and the fifth lens L5 are all spherical surfaces. The material of each lens in the first lens L1, the third lens L3, the fourth lens L4 and the fifth lens L5 is glass; the object side surface and the image side surface of each lens in the second lens L2 and the sixth lens L6 are all aspherical surfaces, and the material of each lens in the second lens L2 and the sixth lens L6 is plastic.

In particular, the combined lens formed by the fourth lens L4 and the fifth lens L5 is arranged as a cemented lens, that is, the fourth lens L4 and the fifth lens L5 are cemented to form the combined lens.

In addition, the lens parameters of the optical system 10 in the third embodiment are given in Table 5 and Table 6, wherein the definitions of the structures and parameters can be obtained from the first embodiment and are not elaborated here.

Table 5

Table 6

Surface number S3 S4 S11 S12 k 5.921E+00 -5.566E-01 5.050E+01 -2.738E+00 A4 1.545E-02 2.385E-02 -5.476E-03 -4.117E-03 A6 -4.220E-03 -8.919E-03 3.882E-03 -3.074E-04 A8 1.211E-03 -1.741E-03 -6.181E-03 1.335E-03 A10 -3.326E-04 3.946E-03 4.598E-03 -1.303E-03 A12 7.011E-05 -2.936E-03 -2.006E-03 5.400E-04 A14 -1.016E-05 1.258E-03 5.329E-04 -1.807E-04 A16 9.451E-07 -5.088E-04 -8.438E-05 2.969E-05 A18 -5.060E-08 3.928E-05 7.280E-06 -2.635E-06 A20 1.182E-09 -1.953E-06 -5.620E-07 9.754E-08

The optical system 10 in this embodiment satisfies the following relationship:

As can be seen from Figures 8 and 9, the longitudinal spherical aberration, field curvature, astigmatism, and distortion of the optical system 10 are all well controlled, wherein the focus shift corresponding to the longitudinal spherical aberration at each wavelength is small, and the meridional field curvature and sagittal field curvature at each field of view are all controlled within 0.050 mm, the image plane curvature is well suppressed, and the astigmatism and distortion are also reasonably adjusted.

Fourth embodiment

10 , in the fourth embodiment, the optical system 10 includes, from the object side to the image side, a first lens L1 having negative refractive power, a second lens L2 having negative refractive power, a third lens L3 having positive refractive power, a stop STO, a fourth lens L4 having positive refractive power, a fifth lens L5 having negative refractive power, and a sixth lens L6 having positive refractive power.

The surface shapes of the lens surfaces in the optical system 10 are as follows:

The object-side surface S1 of the first lens L1 is convex at the near optical axis, and the image-side surface S2 is concave at the near optical axis;

The object-side surface S3 of the second lens L2 is convex at the near optical axis, and the image-side surface S4 is concave at the near optical axis;

The object-side surface S5 of the third lens L3 is convex at the near optical axis, and the image-side surface S6 is convex at the near optical axis;

The object-side surface S7 of the fourth lens L4 is convex at the near optical axis, and the image-side surface S8 is convex at the near optical axis;

The object-side surface S9 of the fifth lens L5 is concave at the near optical axis, and the image-side surface S10 is convex at the near optical axis;

The object-side surface S11 of the sixth lens L6 is convex at the near optical axis, and the image-side surface S12 is convex at the near optical axis.

In addition, the object side surface and the image side surface of each lens in the first lens L1, the third lens L3, the fourth lens L4 and the fifth lens L5 are all spherical surfaces. The material of each lens in the first lens L1, the third lens L3, the fourth lens L4 and the fifth lens L5 is glass; the object side surface and the image side surface of each lens in the second lens L2 and the sixth lens L6 are all aspherical surfaces, and the material of each lens in the second lens L2 and the sixth lens L6 is plastic.

In particular, the combined lens formed by the fourth lens L4 and the fifth lens L5 is arranged as a cemented lens, that is, the fourth lens L4 and the fifth lens L5 are cemented to form the combined lens.

In addition, the lens parameters of the optical system 10 in the fourth embodiment are given in Table 7 and Table 8, wherein the definitions of the structures and parameters can be obtained from the first embodiment and will not be repeated here.

Table 7

Table 8

Surface number S3 S4 S11 S12 k 2.064E+00 -7.689E-01 8.000E+01 -2.674E+00 A4 1.549E-02 2.752E-02 -5.165E-03 -4.141E-03 A6 -4.000E-03 -2.110E-02 2.162E-03 2.247E-04 A8 1.044E-03 1.923E-02 -4.070E-03 5.811E-04 A10 -2.651E-04 -1.613E-02 3.178E-03 -7.363E-04 A12 5.315E-05 8.611E-03 -1.433E-03 3.957E-04 A14 -7.503E-06 -2.846E-03 3.911E-04 -1.185E-04 A16 5.923E-07 5.744E-04 -4.326E-05 2.045E-05 A18 -3.733E-08 -6.624E-05 5.544E-06 -4.894E-06 A20 8.883E-10 3.425E-06 -2.016E-07 7.280E-08

The optical system 10 in this embodiment satisfies the following relationship:

As can be seen from Figures 11 and 12, the longitudinal spherical aberration, field curvature, astigmatism, and distortion of the optical system 10 are all well controlled, wherein the focus shift corresponding to the longitudinal spherical aberration at each wavelength is small, and the meridional field curvature and sagittal field curvature at each field of view are all controlled within 0.050 mm, the image plane curvature is well suppressed, and the astigmatism and distortion are also reasonably adjusted.

Fifth embodiment

13 , in the fifth embodiment, the optical system 10 includes, from the object side to the image side, a first lens L1 having negative refractive power, a second lens L2 having negative refractive power, a third lens L3 having positive refractive power, a stop STO, a fourth lens L4 having positive refractive power, a fifth lens L5 having negative refractive power, and a sixth lens L6 having positive refractive power.

The surface shapes of the lens surfaces in the optical system 10 are as follows:

The object-side surface S1 of the first lens L1 is convex at the near optical axis, and the image-side surface S2 is concave at the near optical axis;

The object-side surface S3 of the second lens L2 is convex at the near optical axis, and the image-side surface S4 is concave at the near optical axis;

The object-side surface S5 of the third lens L3 is convex at the near optical axis, and the image-side surface S6 is convex at the near optical axis;

The object-side surface S7 of the fourth lens L4 is convex at the near optical axis, and the image-side surface S8 is convex at the near optical axis;

The object-side surface S9 of the fifth lens L5 is concave at the near optical axis, and the image-side surface S10 is convex at the near optical axis;

The object-side surface S11 of the sixth lens L6 is convex at the near optical axis, and the image-side surface S12 is convex at the near optical axis.

In addition, the object side surface and the image side surface of each lens in the first lens L1, the third lens L3, the fourth lens L4 and the fifth lens L5 are all spherical surfaces. The material of each lens in the first lens L1, the third lens L3, the fourth lens L4 and the fifth lens L5 is glass; the object side surface and the image side surface of each lens in the second lens L2 and the sixth lens L6 are all aspherical surfaces, and the material of each lens in the second lens L2 and the sixth lens L6 is plastic.

In particular, the combined lens formed by the fourth lens L4 and the fifth lens L5 is arranged as a cemented lens, that is, the fourth lens L4 and the fifth lens L5 are cemented to form the combined lens.

In addition, the lens parameters of the optical system 10 in the fifth embodiment are given in Tables 9 and 10, wherein the definitions of the structures and parameters can be obtained from the first embodiment and will not be repeated here.

Table 9

Table 10

The optical system 10 in this embodiment satisfies the following relationship:

As can be seen from Figures 14 and 15, the longitudinal spherical aberration, field curvature, astigmatism, and distortion of the optical system 10 are all well controlled, wherein the focal shift corresponding to the longitudinal spherical aberration at each wavelength is small, and the meridional field curvature and sagittal field curvature at each field of view are all controlled within 0.050 mm, the image plane curvature is well suppressed, and the astigmatism and distortion are also reasonably adjusted.

In the above first to fifth embodiments, the optical system 10 not only has a wide-angle characteristic through corresponding refractive power, physical parameters, and surface design, but also can effectively suppress the longitudinal spherical aberration, field curvature, astigmatism, and distortion aberration of the optical system 10, thereby achieving high-quality imaging effects.

In addition, referring to FIG. 16 , some embodiments of the present application further provide a camera module 20, which may include the optical system 10 and the image sensor 210 described in any one of the above embodiments, and the image sensor 210 is arranged on the image side of the optical system 10. The image sensor 210 may be a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor). Generally, during assembly, the imaging surface of the optical system 10 overlaps with the photosensitive surface of the image sensor 210. By adopting the above optical system 10, the camera module 20 has a large field of view, the shooting range is expanded, and the imaging effect is good, thereby improving the imaging quality.

Referring to FIG. 17 , some embodiments of the present application further provide an electronic device 30. The electronic device 30 includes a fixing member 310, and the camera module 20 is mounted on the fixing member 310. The fixing member 310 may be a display screen, a touch display screen, a circuit board, a middle frame, a back cover, and other components. The electronic device 30 may be, but is not limited to, a smart phone, a smart watch, smart glasses, an e-book reader, a vehicle-mounted camera device, a monitoring device, a drone, a medical device (such as an endoscope), a tablet computer, a biometric device (such as a fingerprint recognition device or a pupil recognition device, etc.), a PDA (Personal Digital Assistant), a drone, and the like. In some embodiments, when the electronic device 30 is a vehicle-mounted camera device, the camera module 20 may be used as a vehicle-mounted surround view lens of the device, and the fixing member 310 is used to install the electronic device 30 on the vehicle. When the electronic device 30 is used to shoot a scene, the shooting range is wide, the imaging effect is good, and the shooting quality can be well improved.

A vehicle-mounted system includes the above-mentioned electronic device. When the environment inside and outside the cockpit is photographed by the electronic device, since the electronic device has a wide shooting range and good imaging effect, it can effectively ensure that the vehicle-mounted system is provided with a wide-coverage, bright and clear image of the environment inside and outside the cockpit, so that the vehicle-mounted system can more accurately grasp the situation inside and outside the cockpit. When the vehicle-mounted system uses ADAS, DMS, CMS and other systems to analyze the images taken by the electronic device and make control decisions, the control accuracy of ADAS, DMS, CMS and other systems when applied to the vehicle-mounted system is effectively guaranteed, so as to better achieve the goal of safe driving.

The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the invention patent. It should be pointed out that for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be based on the attached claims.

Claims (9)

1. An optical system, characterized in that it comprises successively along the optical axis from the object side to the image side: A first lens with negative refractive power, the object side of the first lens is convex at the near optical axis, and the image side is concave at the near optical axis; A second lens with negative refractive power, the object side of the second lens is convex at the near optical axis, and the image side is concave at the near optical axis; A third lens with positive refractive power, the object side of the third lens is convex at the near optical axis; A fourth lens with positive refractive power, the object side and the image side of the fourth lens are both convex at the near optical axis; A fifth lens with negative refractive power, the object side of the fifth lens is concave at the near optical axis, and the image side is convex at the near optical axis; A sixth lens with positive refractive power, the object side and the image side of the sixth lens are both convex at the near optical axis; There are six lenses with refractive power; A diaphragm is set between the third lens and the fourth lens, and the optical system satisfies the conditional formula: 60.00deg/mm<FOV/AT2<105.00deg/mm; 8.64≤SDs1/Sags1≤11.13; Wherein, FOV is the maximum field of view angle of the optical system, AT2 is the distance between the image side of the second lens and the object side of the third lens on the optical axis, SDs1 is the object side of the first lens Half of the maximum effective aperture, Sags1 is the sagittal height of the object side of the first lens at the maximum effective aperture. 2. The optical system according to claim 1, wherein the optical system satisfies the conditional formula: 1.50<f456/f<2.50; Wherein, f is the effective focal length of the optical system, and f456 is the combined focal length of the fourth lens, the fifth lens and the sixth lens. 3. The optical system according to claim 1, wherein the optical system satisfies the conditional formula: 1.20<CT4/AT3<2.00; Wherein, CT4 is the thickness of the fourth lens on the optical axis, AT3 is the distance between the image side of the third lens and the object side of the fourth lens on the optical axis. 4. The optical system according to claim 1, wherein the optical system satisfies the conditional formula: 2.00＜|Rs12/Sags12|＜5.00; Wherein, Rs12 is the radius of curvature of the image side of the sixth lens at the optical axis, and Sags12 is the sagittal height of the image side of the sixth lens at the maximum effective aperture. 5. The optical system according to claim 1, wherein the optical system satisfies the conditional formula: 70.00deg＜(FOV×f)/ImgH＜90.00deg; Wherein, f is the effective focal length of the optical system, and ImgH is half of the image height corresponding to the maximum viewing angle of the optical system. 6. The optical system according to claim 1, wherein the optical system satisfies the conditional formula: 2.00<|f2/CT2|<3.50; Wherein, f2 is the effective focal length of the second lens, and CT2 is the thickness of the second lens on the optical axis. 7. A camera module, characterized by comprising an image sensor and the optical system according to any one of claims 1 to 6, the image sensor being arranged on the image side of the optical system. 8. An electronic device, characterized by comprising a fixing part and the camera module according to claim 7, the camera module being arranged on the fixing part. 9. A vehicle-mounted system, comprising the electronic device according to claim 8.