阅读说明：本技术 光学镜头 (Optical lens ) 是由 姜欢 王东方 姚波 于 2018-05-28 设计创作，主要内容包括：本申请公开了一种光学镜头,该光学镜头沿着光轴由物侧至像侧依序可包括：第一透镜、第二透镜、第三透镜、第四透镜、第五透镜、第六透镜和第七透镜。其中第一透镜可具有负光焦度,其物侧面为凸面,像侧面为凹面；第二透镜可具有负光焦度,其物侧面和像侧面均为凹面；第三透镜可具有正光焦度；第四透镜可具有正光焦度,其物侧面和像侧面均为凸面；第五透镜可具有负光焦度,其物侧面为凸面,像侧面为凹面；第六透镜可具有正光焦度,其物侧面和像侧面均为凸面；以及第七透镜可具有负光焦度,其物侧面为凹面,像侧面为凸面。根据本申请的光学镜头,可实现小型化、高解像、低成本、后焦长等中的至少一个有益效果。(The present application discloses an optical lens, which sequentially comprises, from an object side to an image side along an optical axis: the lens includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens. The first lens can have negative focal power, and the object side surface of the first lens is a convex surface, and the image side surface of the first lens is a concave surface; the second lens can have negative focal power, and both the object side surface and the image side surface of the second lens are concave; the third lens may have a positive optical power; the fourth lens can have positive focal power, and both the object side surface and the image side surface of the fourth lens are convex surfaces; the fifth lens element has negative focal power, and has a convex object-side surface and a concave image-side surface; the sixth lens element can have a positive focal power, and both the object-side surface and the image-side surface of the sixth lens element are convex; and the seventh lens element can have a negative power, and its object-side surface is concave and its image-side surface is convex. According to the optical lens of the present application, at least one of advantageous effects of miniaturization, high resolution, low cost, back focal length, and the like can be achieved.)

1. The optical lens sequentially comprises from an object side to an image side along an optical axis: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens,

It is characterized in that the preparation method is characterized in that,

The first lens has negative focal power, the object side surface of the first lens is a convex surface, and the image side surface of the first lens is a concave surface;

The second lens has negative focal power, and both the object side surface and the image side surface of the second lens are concave;

The third lens has positive optical power;

The fourth lens has positive focal power, and both the object side surface and the image side surface of the fourth lens are convex surfaces;

The fifth lens has negative focal power, the object side surface of the fifth lens is a convex surface, and the image side surface of the fifth lens is a concave surface;

The sixth lens has positive focal power, and both the object side surface and the image side surface of the sixth lens are convex surfaces; and

The seventh lens element has a negative focal power, and has a concave object-side surface and a convex image-side surface.

2. An optical lens according to claim 1, wherein the fifth lens, the sixth lens and the seventh lens are cemented together to form a cemented triplet.

3. An optical lens barrel according to claim 1, wherein the object-side surface and the image-side surface of the third lens are convex.

4. An optical lens barrel according to claim 1, wherein the third lens element has a concave object-side surface and a convex image-side surface.

5. An optical lens according to claim 1, wherein the first lens to the seventh lens are all glass lenses.

6. An optical lens according to claim 1, characterized in that the optical lens has at most three aspherical lenses.

7. an optical lens according to claim 6, characterized in that one or all of the third and fourth lenses are aspherical lenses.

8. An optical lens according to claim 6, characterized in that the seventh lens is an aspherical mirror.

9. An optical lens according to claim 7, characterized in that the seventh lens is an aspherical mirror.

10. An optical lens according to any one of claims 1 to 9, characterized in that the conditional expression is satisfied: D/H/FOV is less than or equal to 0.025,

Wherein the FOV is the maximum field angle of the optical lens;

D is the maximum light-passing aperture of the object-side surface of the first lens corresponding to the maximum field angle of the optical lens; and

And H is the image height corresponding to the maximum field angle of the optical lens.

11. An optical lens barrel according to any one of claims 1 to 9, wherein a distance TTL between a center of an object side surface of the first lens and an imaging surface of the optical lens on the optical axis and a full group focal length value F of the optical lens satisfy: TTL/F is less than or equal to 7.5.

12. An optical lens according to any one of claims 1 to 9, characterized in that the conditional expression is satisfied: the BFL/TTL is more than or equal to 0.13,

The BFL is the distance from the center of the image side surface of the seventh lens to the imaging surface of the optical lens on the optical axis; and

TTL is a distance on the optical axis from the center of the object-side surface of the first lens element to the imaging surface of the optical lens.

13. the optical lens sequentially comprises from an object side to an image side along an optical axis: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens,

It is characterized in that the preparation method is characterized in that,

the first lens, the second lens, the fifth lens, and the seventh lens each have a negative optical power;

The third lens, the fourth lens and the sixth lens each have positive optical power; and

The fifth lens, the sixth lens and the seventh lens are cemented with each other to form a cemented triplet,

The distance TTL from the center of the object side surface of the first lens to the imaging surface of the optical lens on the optical axis and the whole group of focal length values F of the optical lens satisfy the following conditions: TTL/F is less than or equal to 7.5.

Technical Field

The present application relates to an optical lens, and more particularly, to an optical lens including seven lenses.

Background

With the scientific technology becoming more mature, the emerging technologies such as unmanned driving and the like become more and more popular, and the imaging requirements on the lens become higher and higher. Especially, the resolution of the on-vehicle lens is gradually improved in the 8M and 12M directions.

Disclosure of Invention

The present application provides an optical lens that is adaptable for on-board installation and that overcomes, at least in part, at least one of the above-identified deficiencies in the prior art.

An aspect of the present application provides an optical lens that may include, in order from an object side to an image side along an optical axis: the lens includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens. The first lens can have negative focal power, and the object side surface of the first lens is a convex surface, and the image side surface of the first lens is a concave surface; the second lens can have negative focal power, and both the object side surface and the image side surface of the second lens are concave; the third lens may have a positive optical power; the fourth lens can have positive focal power, and both the object side surface and the image side surface of the fourth lens are convex surfaces; the fifth lens element has negative focal power, and has a convex object-side surface and a concave image-side surface; the sixth lens element can have a positive focal power, and both the object-side surface and the image-side surface of the sixth lens element are convex; and the seventh lens element can have a negative power, and its object-side surface is concave and its image-side surface is convex.

In one embodiment, the fifth lens, the sixth lens, and the seventh lens may be cemented with each other to form a cemented triplet.

In one embodiment, both the object-side surface and the image-side surface of the third lens can be convex.

in another embodiment, the object-side surface of the third lens element can be concave and the image-side surface can be convex.

In one embodiment, each of the first to seventh lenses may be a glass lens.

In one embodiment, the optical lens may have up to three aspheric lenses. Alternatively, one or both of the third lens and the fourth lens may be aspherical lenses. Alternatively or additionally, the seventh lens may be an aspherical mirror.

In one embodiment, the conditional formula may be satisfied: D/H/FOV is less than or equal to 0.025, wherein the FOV is the maximum field angle of the optical lens; d is the maximum light-passing aperture of the object-side surface of the first lens corresponding to the maximum field angle of the optical lens; and H is the image height corresponding to the maximum field angle of the optical lens.

In one embodiment, a distance TTL between a center of an object side surface of the first lens element and an imaging surface of the optical lens on an optical axis and a full-group focal length value F of the optical lens may satisfy: TTL/F is less than or equal to 7.5.

in one embodiment, the conditional formula may be satisfied: BFL/TTL is more than or equal to 0.13, wherein BFL is the distance from the center of the image side surface of the seventh lens to the imaging surface of the optical lens on the optical axis; and TTL is the distance from the center of the object side surface of the first lens to the imaging surface of the optical lens on the optical axis.

Another aspect of the present application provides an optical lens that may include, in order from an object side to an image side along an optical axis: the lens includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens. The first lens, the second lens, the fifth lens and the seventh lens all have negative focal power; the third lens, the fourth lens and the sixth lens may each have positive optical power; and the fifth lens, the sixth lens and the seventh lens can be mutually glued to form a triple cemented lens, wherein the distance TTL from the center of the object side surface of the first lens to the imaging surface of the optical lens on the optical axis and the whole group focal length value F of the optical lens can satisfy the following conditions: TTL/F is less than or equal to 7.5.

in one embodiment, the object-side surface of the first lens element can be convex and the image-side surface can be concave.

In one embodiment, both the object-side surface and the image-side surface of the second lens can be concave.

In one embodiment, both the object-side surface and the image-side surface of the third lens can be convex.

in another embodiment, the object-side surface of the third lens element can be concave and the image-side surface can be convex.

In one embodiment, both the object-side surface and the image-side surface of the fourth lens can be convex.

in one embodiment, the object-side surface of the fifth lens element can be convex and the image-side surface can be concave.

In one embodiment, both the object-side surface and the image-side surface of the sixth lens element can be convex.

In one embodiment, the object-side surface of the seventh lens element can be concave and the image-side surface can be convex.

In one embodiment, each of the first to seventh lenses may be a glass lens.

In one embodiment, the optical lens may have up to three aspheric lenses. Alternatively, one or both of the third lens and the fourth lens may be aspherical lenses. Alternatively or additionally, the seventh lens may be an aspherical mirror.

In one embodiment, the conditional formula may be satisfied: D/H/FOV is less than or equal to 0.025, wherein the FOV is the maximum field angle of the optical lens; d is the maximum light-passing aperture of the object-side surface of the first lens corresponding to the maximum field angle of the optical lens; and H is the image height corresponding to the maximum field angle of the optical lens.

In one embodiment, the conditional formula may be satisfied: BFL/TTL is more than or equal to 0.13, wherein BFL is the distance from the center of the image side surface of the seventh lens to the imaging surface of the optical lens on the optical axis; and TTL is the distance from the center of the object side surface of the first lens to the imaging surface of the optical lens on the optical axis.

The optical lens adopts seven lenses, and at least one of the beneficial effects of high resolution, miniaturization, low cost, back focal length and the like of the optical lens is realized by optimally setting the shapes of the lenses, reasonably distributing the focal power of each lens and the like.

Drawings

Other features, objects, and advantages of the present application will become more apparent from the following detailed description of non-limiting embodiments when taken in conjunction with the accompanying drawings. In the drawings:

Fig. 1 is a schematic view showing a structure of an optical lens according to embodiment 1 of the present application;

fig. 2 is a schematic structural view showing an optical lens according to embodiment 2 of the present application; and

Fig. 3 is a schematic view showing a structure of an optical lens according to embodiment 3 of the present application.

Detailed Description

For a better understanding of the present application, various aspects of the present application will be described in more detail with reference to the accompanying drawings. It should be understood that the detailed description is merely illustrative of exemplary embodiments of the present application and does not limit the scope of the present application in any way. Like reference numerals refer to like elements throughout the specification. The expression "and/or" includes any and all combinations of one or more of the associated listed items.

it should be noted that in this specification, the expressions first, second, third, etc. are used only to distinguish one feature from another, and do not represent any limitation on the features. Thus, the first lens discussed below may also be referred to as the second lens or the third lens, and the first cemented lens may also be referred to as the second cemented lens, without departing from the teachings of the present application.

In the drawings, the thickness, size, and shape of the lens have been slightly exaggerated for convenience of explanation. In particular, the shapes of the spherical or aspherical surfaces shown in the drawings are shown by way of example. That is, the shape of the spherical surface or the aspherical surface is not limited to the shape of the spherical surface or the aspherical surface shown in the drawings. The figures are purely diagrammatic and not drawn to scale.

Herein, the paraxial region refers to a region near the optical axis. If the lens surface is convex and the convex position is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the concave position is not defined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the object is called the object side surface, and the surface of each lens closest to the image plane is called the image side surface.

It will be further understood that the terms "comprises," "comprising," "has," "having," "includes" and/or "including," when used in this specification, specify the presence of stated features, elements, and/or components, but do not preclude the presence or addition of one or more other features, elements, components, and/or groups thereof. Moreover, when a statement such as "at least one of" appears after a list of listed features, the entirety of the listed features is modified rather than modifying individual elements in the list. Furthermore, when describing embodiments of the present application, the use of "may" mean "one or more embodiments of the present application. Also, the term "exemplary" is intended to refer to an example or illustration.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present application will be described in detail below with reference to the embodiments with reference to the attached drawings.

The features, principles, and other aspects of the present application are described in detail below.

An optical lens according to an exemplary embodiment of the present application includes, for example, seven lenses having optical power, i.e., a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens. The seven lenses are arranged in order from the object side to the image side along the optical axis.

the optical lens according to the exemplary embodiment of the present application may further include a photosensitive element disposed on the image plane. Alternatively, the photosensitive element provided to the imaging surface may be a photosensitive coupling element (CCD) or a complementary metal oxide semiconductor element (CMOS).

The first lens element can have a negative power, and can have a convex object-side surface and a concave image-side surface. The first lens is arranged in a meniscus shape which is convex to the object side, so that light rays with large angles can be collected as far as possible, and the light rays enter a rear optical system. In practical application, the vehicle-mounted lens outdoor installation and use environment is considered, the vehicle-mounted lens outdoor installation and use environment can be in severe weather such as rain and snow, the design of the meniscus shape protruding towards the object side is more suitable for the environment such as rain and snow, the water drops can slide off, and therefore the influence of the external environment on imaging is reduced.

The second lens can have a negative optical power, and both the object-side surface and the image-side surface can be concave. The biconcave second lens can collect light rays with a large view field as much as possible, so that the light rays can stably enter a rear optical system; and the biconcave shape design is favorable to reducing the air interval between second lens and the third lens, is changeably shortened the physical total length of camera lens, realizes the miniaturization characteristic.

the third lens may have a positive optical power. The third lens can transit light, so that the light can stably enter the rear optical system.

The fourth lens element can have a positive optical power, and can have a convex object-side surface and a convex image-side surface. The fourth lens can disperse the light converged by the front lens, so that the light can smoothly enter the rear system.

The fifth lens element can have a negative power, and can have a convex object-side surface and a concave image-side surface.

The sixth lens element can have a positive optical power, and can have a convex object-side surface and a convex image-side surface.

The seventh lens element can have a negative power, and can have a concave object-side surface and a convex image-side surface.

As known to those skilled in the art, cemented lenses may be used to minimize or eliminate chromatic aberration. The use of the cemented lens in the optical lens can improve the image quality and reduce the reflection loss of light energy, thereby improving the imaging definition of the lens. In addition, the use of the cemented lens can also simplify the assembly process in the lens manufacturing process.

in an exemplary embodiment, the fifth lens, the sixth lens, and the seventh lens may be combined into a triple cemented lens by cementing the image-side surface of the fifth lens with the object-side surface of the sixth lens, and cementing the image-side surface of the sixth lens with the object-side surface of the seventh lens. By introducing the triple cemented lens consisting of the fifth lens, the sixth lens and the seventh lens, the chromatic aberration influence can be eliminated, the field curvature is reduced, and the coma is corrected; meanwhile, the cemented lens may also retain a part of chromatic aberration to balance the entire chromatic aberration of the optical system. The air space between the three lenses is reduced by gluing the lenses, so that the whole optical system is compact, the total length of the system is favorably reduced, and the requirement of system miniaturization is met. The gluing of the lenses can reduce the number of assembling parts between the three lenses, reduce the assembling process, reduce the cost, and reduce the tolerance sensitivity problem of the lens unit caused by inclination/decentration in the assembling process. Moreover, the gluing of the lenses is beneficial to reducing the light quantity loss caused by reflection between the lenses, and the system illumination can be improved. The gluing of the lens can increase the back focal length, realize the assembly of the effective space, make the lens suitable for the special application field; and a space is reserved for the installation and focusing of the optical element, so that the interference between mechanisms is avoided.

in an exemplary embodiment, a diaphragm for limiting the light beam may be disposed between, for example, the third lens and the fourth lens to further improve the imaging quality of the lens.

in an exemplary embodiment, the maximum field angle FOV of the optical lens, the maximum clear aperture D of the object-side surface of the first lens corresponding to the maximum field angle of the optical lens, and the image height H corresponding to the maximum field angle of the optical lens may satisfy: D/H/FOV is less than or equal to 0.025, and more desirably D, H and FOV further satisfy D/H/FOV is less than or equal to 0.02. The conditional expression D/H/FOV is less than or equal to 0.025, and the small caliber at the front end of the lens can be ensured.

In an exemplary embodiment, an optical total length TTL of the optical lens and a whole set of focal length values F of the optical lens may satisfy: TTL/F is less than or equal to 7.5, and more ideally, TTL and F further satisfy that TTL/F is less than or equal to 7. The TTL/F is less than or equal to 7.5, and the miniaturization characteristic of the lens can be ensured.

In an exemplary embodiment, the optical back focus BFL of the optical lens and the total optical length TTL of the optical lens may satisfy that BFL/TTL is greater than or equal to 0.13, and further, the BFL and TTL may further satisfy that BFL/TTL is greater than or equal to 0.15. The setting that BFL/TTL is more than or equal to 0.13 is met, so that the back focal length of the lens is long enough, the assembly of an effective space can be realized, and the lens can be suitable for special application fields; and a space can be reserved for the installation and focusing of the optical element, so that the interference between mechanisms is avoided.

In an exemplary embodiment, the number of lenses using an aspherical lens in an optical lens according to the present application is three or less. The aspheric lens has the characteristics that: the curvature varies continuously from the center of the lens to the periphery. Unlike a spherical lens having a constant curvature from the center to the periphery of the lens, an aspherical lens has better curvature radius characteristics, and has the advantages of improving distortion aberration and improving astigmatic aberration. After the aspheric lens is adopted, the aberration generated in imaging can be eliminated as much as possible, so that the imaging quality of the lens is improved. For example, in the optical lens according to the present application, one or more of the third lens, the fourth lens and the seventh lens may adopt an aspheric lens to further improve the resolution quality and reduce the aberration.

In an exemplary embodiment, the lens used in the optical lens may be a plastic lens, or may be a glass lens. The lens made of plastic has a large thermal expansion coefficient, and when the ambient temperature change of the lens is large, the lens made of plastic has a large influence on the overall performance of the lens. The glass lens can reduce the influence of temperature on the performance of the lens. Ideally, the first lens to the seventh lens in the optical lens according to the present application are all glass lenses, so as to reduce the influence of the environment on the whole system and improve the overall performance of the optical lens.

According to the optical lens of the above embodiment of the application, the lens shape is optimally set, the focal power is reasonably distributed, the TTL can be shortened, and the resolution is improved while the miniaturization of the lens is ensured. The optical lens according to the application uses 7 glass lenses, so that the imaging quality (up to 12M resolution) can be improved, and the stable performance at different temperatures can be ensured; in the conventional 12M image-resolving lens, 4 or more aspheric lenses are usually used to improve the image-resolving performance of the lens; but the number of the aspheric lenses is reduced, and the cost can be reduced; and the fifth lens, the sixth lens and the seventh lens are glued, so that the total length of the system is shortened, long back focus can be realized, and the miniaturization is realized. Therefore, the optical lens according to the present application has the characteristics of high image resolution, high illumination, long back focus, short total length, and high image restoration degree, and is more suitable for use in a vehicle-mounted environment.

However, it will be appreciated by those skilled in the art that the number of lenses constituting the lens barrel may be varied to achieve the various results and advantages described in the present specification without departing from the claimed subject matter. For example, although seven lenses are exemplified in the embodiment, the optical lens is not limited to include seven lenses. The optical lens may also include other numbers of lenses, if desired.

Specific examples of an optical lens applicable to the above-described embodiments are further described below with reference to the drawings.