CN110412726B - Optical lens - Google Patents

Abstract

The present application discloses an optical lens, sequentially from an object side to an image side along an optical axis, comprising: 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 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 positive focal power, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface; the third lens and the fourth lens are glued to form a first cemented lens; the fifth lens and the sixth lens are glued to form a second cemented lens; and the object side surface of the seventh lens is a concave surface, and the image side surface of the seventh lens is a convex surface.

Description

Optical lens

Technical Field

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

Background

Currently, a vehicle-mounted lens is generally applied to a vehicle-mounted driving assistance system to assist a driver in driving, even to automatically drive. However, with the development and popularization of the unmanned technology, the pixel requirement for the vehicle-mounted lens is higher and higher.

The conventional technology generally increases the number of lenses to more than six sheets to obtain higher resolution capability. However, increasing the number of lenses affects miniaturization of the lens, which is not favorable for installation and use of the lens, and also increases the cost of the lens. In addition, an aspheric lens is generally used to correct aberration in the conventional art, and when a plastic aspheric lens is used, there is a problem of out-of-focus image blur caused by temperature change due to a large coefficient of thermal expansion of plastic; when a glass aspheric lens is used, the cost of the lens is too high.

Therefore, it is desirable to provide an optical lens that is applicable to vehicle-mounted mounting, has good temperature stability, has high resolving power, and satisfies both miniaturization and low cost.

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.

In one aspect, the present application provides an optical lens, in order from an object side to an image side along an optical axis, comprising: 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 object side surface of the first lens can be a convex surface, and the image side surface of the first lens can be a concave surface; the second lens can have positive focal power, and the object side surface of the second lens can be a convex surface, and the image side surface of the second lens can be a concave surface; the third lens and the fourth lens can be glued to form a first cemented lens; the fifth lens and the sixth lens can be cemented to form a second cemented lens; and the object side surface of the seventh lens element can be concave, and the image side surface can be convex.

In one embodiment, the first lens may have a negative optical power.

In one embodiment, the first lens may have a positive optical power.

In one embodiment, the third lens of the first cemented lens may have a negative optical power, and both the object-side surface and the image-side surface thereof may be concave; and the fourth lens in the first cemented lens may have positive optical power, and both the object-side surface and the image-side surface thereof may be convex.

In one embodiment, the fifth lens of the second cemented lens may have positive optical power, and both the object-side surface and the image-side surface thereof may be convex; and the object side surface of the sixth lens in the second cemented lens may be concave.

In one embodiment, 2 ≦ f34/f ≦ 6 may be satisfied between the combined focal length f34 of the third lens and the fourth lens and the entire group focal length f of the optical lens.

In one embodiment, 0.2 ≦ f56/f ≦ 2.5 may be satisfied between the combined focal length f56 of the fifth lens and the sixth lens and the entire group focal length f of the optical lens.

In one embodiment, the total optical length TTL of the optical lens and the whole group focal length f of the optical lens can satisfy that TTL/f is less than or equal to 2.8.

In one embodiment, a radius of curvature R71 of the object-side surface of the seventh lens and a radius of curvature R72 of the image-side surface of the seventh lens may satisfy: R72/R71 is more than or equal to 0 and less than or equal to 8.

In another aspect, the present disclosure 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 object side surface of the first lens can be a convex surface, and the image side surface of the first lens can be a concave surface; the second lens can have positive focal power, and the object side surface of the second lens can be a convex surface, and the image side surface of the second lens can be a concave surface; the third lens can have negative focal power, and both the object side surface and the image side surface of the third lens can be concave; the fourth lens can have positive focal power, and both the object side surface and the image side surface of the fourth lens can be convex surfaces; the fifth lens can have positive focal power, and both the object side surface and the image side surface of the fifth lens can be convex surfaces; the object side surface of the sixth lens can be a concave surface; the object side surface of the seventh lens element can be a concave surface, and the image side surface can be a convex surface; and the total optical length TTL of the optical lens and the whole group focal length f of the optical lens can meet the condition that TTL/f is less than or equal to 2.8.

In one embodiment, the first lens may have a negative optical power.

In one embodiment, the first lens may have a positive optical power.

In one embodiment, the third lens and the fourth lens can be cemented to form a first cemented lens.

In one embodiment, the fifth lens and the sixth lens may be cemented to form a second cemented lens.

In one embodiment, the image-side surface of the sixth lens element may be convex.

In one embodiment, the image side surface of the sixth lens may be concave.

In one embodiment, 2 ≦ f34/f ≦ 6 may be satisfied between the combined focal length f34 of the third lens and the fourth lens and the entire group focal length f of the optical lens.

In one embodiment, 0.2 ≦ f56/f ≦ 2.5 may be satisfied between the combined focal length f56 of the fifth lens and the sixth lens and the entire group focal length f of the optical lens.

In one embodiment, a radius of curvature R71 of the object-side surface of the seventh lens and a radius of curvature R72 of the image-side surface of the seventh lens may satisfy 0 ≦ R72/R71 ≦ 8.

The optical lens adopts seven lenses, and the optical lens has at least one beneficial effect of high resolution, miniaturization, low cost and the like by optimally setting the shapes of the lenses, reasonably distributing the focal power of the lenses, and forming a cemented lens by gluing.

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;

fig. 3 is a schematic structural view showing an optical lens according to embodiment 3 of the present application;

fig. 4 is a schematic structural view showing an optical lens according to embodiment 4 of the present application; and

fig. 5 is a schematic view showing a structure of an optical lens according to embodiment 5 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 closer to the object side in each lens is referred to as the object side surface of the lens, and the surface closer to the image side in each lens is referred to as the image side surface of the lens.

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).

According to the embodiments of the present disclosure, the object-side surface of the first lens element may be a convex surface, the image-side surface of the first lens element may be a concave surface, and the object-side surface of the first lens element is disposed in a meniscus shape with the convex surface facing the object side, so as to collect light rays with a large field of view as much as possible, allow as much light rays as possible to enter the rear optical system, and increase the light flux of the lens. In some embodiments, the first lens may have a negative power, and the first lens with a negative power may collect more light into the posterior optical system, facilitating high angle applications. In some embodiments, the first lens may have a positive optical power, and configuring the first lens to have a positive optical power is advantageous for achieving a better image resolution effect.

The second lens element can have a positive power, and can have a convex object-side surface and a concave image-side surface. The second lens has positive focal power, which is beneficial to compressing the light collected by the first lens, thereby smoothly transiting the light or converging the light to the third lens.

The third lens and the fourth lens may be cemented to form a first cemented lens. The third lens element can have a negative optical power, and can have a concave object-side surface and a concave image-side surface. 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 may be made of a material having a high refractive index; meanwhile, the third lens can be made of a material with a low refractive index (relative to a material for forming the fourth lens), and the matching of the high refractive index and the low refractive index is beneficial to the rapid transition of the front light and the increase of the aperture of the diaphragm, so that the lens meets the night vision requirement. In addition, the use of the cemented lens can effectively reduce the chromatic aberration of the system, make the whole structure of the optical system more compact, and reduce the tolerance sensitivity problem of the lens unit such as inclination or decentration generated in the assembling process. In some embodiments, the focal length f34 of the first cemented lens composed of the third lens and the fourth lens cemented together and the entire group focal length f of the optical lens may satisfy 2 ≦ f34/f ≦ 6, more specifically, f34 and f may further satisfy 3.3 ≦ f34/f ≦ 4.8, for example, 3.55 ≦ f34/f ≦ 4.51. And the focal power is reasonably distributed, so that the total length of the system is favorably shortened, and the imaging quality is improved.

The fifth lens and the sixth lens may be cemented to form a second cemented lens, wherein the fifth lens and the sixth lens may be cemented in a variety of configurations. For example, the fifth lens may be a double convex lens having a positive power, and the sixth lens cemented with the fifth lens may be a meniscus lens convex to the image side having a negative power. For another example, the fifth lens may be a double convex lens having a positive power, and the sixth lens cemented with the fifth lens may be a double concave lens having a negative power. For another example, the fifth lens may be a double convex lens having a positive power, and the sixth lens cemented with the fifth lens may be a meniscus lens convex to the image side having a positive power. In an exemplary embodiment, 0.2 ≦ f56/f ≦ 2.5 may be satisfied between the combined focal length f56 of the fifth lens and the sixth lens and the entire group focal length f of the optical lens, and more specifically, f56 and f may further satisfy 0.8 ≦ f56/f ≦ 2.0, for example, 1.00 ≦ f56/f ≦ 1.79. And the focal power is reasonably distributed, so that the total length of the system is favorably shortened, and the imaging quality is improved.

As known to those skilled in the art, discrete lenses at ray breaks are susceptible to manufacturing and/or assembly errors, and the use of cemented lenses can effectively reduce the sensitivity of the system. In the application, two groups of cemented lenses (the first cemented lens and the second cemented lens) are used, so that not only can the sensitivity of the system be effectively reduced and the overall length of the system be shortened, but also the overall chromatic aberration and the aberration correction of the system can be shared, and the resolving power of the optical lens is improved.

The first cemented lens and the second cemented lens may each include a lens having a positive refractive power and a lens having a negative refractive power. One lens has a high refractive index, the other lens has a low refractive index (relative to the lens with the high refractive index), and the matching of the high refractive index and the low refractive index of the lens is favorable for the rapid transition of the front light and the increase of the aperture of the diaphragm, so that the lens meets the requirement of night vision. The use of the cemented lens can also make the overall structure of the optical system more compact while effectively reducing the chromatic aberration of the system. Furthermore, the lens with positive focal power is arranged in front of the lens with negative focal power, so that the curvature of field can be effectively reduced, the off-axis point aberration of the system can be corrected, and the optical performances such as distortion, a principal ray angle (CRA) and the like can be optimized.

The seventh lens element has positive or negative power, and has a concave object-side surface and a convex image-side surface. In some embodiments, the seventh lens element may have a negative power, and the seventh lens element having a negative power may diverge light passing through the sixth lens element, so that the light is smoothly transited to the image plane, which is beneficial to shorten the total length of the system. In other embodiments, the seventh lens may have a positive power, and the seventh lens is configured to have a positive power to facilitate a smaller CRA and a higher relative illumination, so that the image brightness is more uniform. In an exemplary embodiment, the seventh lens may satisfy the conditional expression 0 ≦ R72/R71 ≦ 8, where R71 is a radius of curvature of an object-side surface of the seventh lens, and R72 is a radius of curvature of an image-side surface of the seventh lens. More specifically, R71 and R72 may further satisfy 0. ltoreq. R72/R71. ltoreq.7, for example, 0.48. ltoreq. R72/R71. ltoreq.6.38.

In an exemplary embodiment, a stop may be provided, for example, between the second lens and the third lens (more specifically, between the second lens and the first cemented lens) to improve the imaging quality of the lens barrel. The arrangement of the diaphragm is beneficial to effectively collecting light rays entering the optical system and reducing the aperture of the optical lens. It is to be understood that the stop position is not limited to between the second lens and the third lens, and the stop may be disposed at any other position as needed.

In an exemplary embodiment, TTL/f ≦ 2.8 may be satisfied between the total optical length TTL of the optical lens and the entire group focal length f of the optical lens, and more specifically, TTL and f may further satisfy TTL/f ≦ 2.5, e.g., 1.67 ≦ TTL/f ≦ 2.31. The condition formula TTL/f is less than or equal to 2.8, and the miniaturization of the lens is favorably realized.

In the optical lens according to the exemplary embodiment of the present application, a spherical glass lens is often used, so that the requirement of high resolution can be satisfied, and the requirements of low cost and stable temperature performance can be satisfied. However, in the case of focusing on the resolution without considering the cost or requiring low temperature performance, glass or plastic aspheric lenses are often used to make the optical performance of the lens better.

The optical lens according to the above embodiment of the present application may have the advantages of high resolution, miniaturization, low cost, and the like, and may better meet the requirements of an in-vehicle lens. In particular, the optical lens according to the present application can achieve a high resolution effect of up to 2M pixels or more.

The lens barrel according to the above-described embodiment of the present application may employ a plurality of lenses, for example, seven lenses as described above. Through reasonable distribution of focal power, surface type and focal length of each lens, thickness of each lens, on-axis distance and the like, the lens has the characteristics of high resolution, high imaging quality, low cost and thermal stability while meeting the miniaturization requirement. In addition, the lens configured in the mode can have the performances of compact structure, light weight, good shock resistance and poor heat dissipation, so that the lens can better meet the vehicle-mounted requirements.

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.

Example 1

An optical lens according to embodiment 1 of the present application is described below with reference to fig. 1. Fig. 1 shows a schematic structural diagram of an optical lens according to embodiment 1 of the present application.

As shown in fig. 1, the optical lens includes, in order from the object side to the image side along the optical axis, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, and a seventh lens L7.

The first lens L1 is a meniscus lens with positive power, with the object side S1 being convex and the image side S2 being concave. The second lens L2 is a meniscus lens with positive power, with the object side S3 being convex and the image side S4 being concave. The third lens L3 is a biconcave lens with negative optical power, and both the object-side surface S6 and the image-side surface S7 are concave. The fourth lens L4 is a biconvex lens with positive optical power, and has both the object-side surface S7 and the image-side surface S8 convex. The fifth lens L5 is a biconvex lens with positive optical power, and has both the object-side surface S9 and the image-side surface S10 convex. The sixth lens L6 is a meniscus lens with negative power, and has a concave object-side surface S10 and a convex image-side surface S11. The seventh lens L7 is a meniscus lens with negative power, with the object side S12 being concave and the image side S13 being convex. The third lens L3 and the fourth lens L4 are cemented together to form a first cemented lens, and the fifth lens L5 and the sixth lens L6 are cemented together to form a second cemented lens.

In the optical lens of the present embodiment, a stop STO may be provided between, for example, the second lens L2 and the third lens L3 to improve the imaging quality. Optionally, the optical lens may further include a filter L8 having an object-side surface S14 and an image-side surface S15, and a protective lens L9 having an object-side surface S16 and an image-side surface S17. Filter L8 can be used to correct for color deviations. The protective lens L9 may be used to protect the image sensing chip on the imaging plane IMA. Light from the object passes through each of the surfaces S1 to S17 in sequence and is finally imaged on the imaging plane IMA.

Table 1 shows a radius of curvature R, a thickness T, a refractive index Nd, and an abbe number Vd of each lens of the optical lens of example 1, where the radius of curvature R and the thickness T are both in units of millimeters (mm).

Flour mark	Radius of curvature R	Thickness T	Refractive index Nd	Abbe number Vd
					S1	34.7765	2.5000	1.90	31.3
S2	56.3990	0.5000
					S3	9.2555	2.3000	1.76	27.5
S4	29.9876	0.3000
					STO	All-round	0.6000
S6	-11.1181	1.0000	1.65	33.8
					S7	15.4932	3.0000	1.88	40.8
S8	-15.2087	0.1000
					S9	22.0732	3.8708	1.80	46.6
S10	-13.9355	2.2500	1.78	25.7
					S11	-42.6941	0.9720
S12	-5.2487	2.2500	1.76	27.5
					S13	-25.7722	0.5000
S14	All-round	0.5500	1.52	64.2
					S15	All-round	0.8702
S16	All-round	0.4000	1.52	64.2
					S17	All-round	0.1250
IMA	All-round

TABLE 1

In this embodiment, the object-side surface and the image-side surface of any one of the first lens to the seventh lens are spherical surfaces.

Table 2 below gives the combined focal length f34 of the third lens L3 and the fourth lens L4, the combined focal length f56 of the fifth lens L5 and the sixth lens L6, the entire group focal length f of the optical lens, and the total optical length TTL of the optical lens (i.e., the on-axis distance from the center of the object-side surface S1 of the first lens L1 to the imaging surface IMA) in embodiment 1.

Parameter(s)	f34(mm)	f56(mm)	f(mm)	TTL(mm)
					Numerical value	46.393	18.553	13.037	22.088

TABLE 2

In the present embodiment, f34/f 3.558 is satisfied between the combined focal length f34 of the third lens L3 and the fourth lens L4 of the optical lens and the entire group focal length f of the optical lens; f56/f is 1.423 between the combined focal length f56 of the fifth lens L5 and the sixth lens L6 and the whole group focal length f of the optical lens; the total optical length TTL of the optical lens and the whole group focal length f of the optical lens meet the condition that TTL/f is 1.694; R72/R71 ═ 4.910 between the radius of curvature R71 of the object-side surface S12 of the seventh lens L7 and the radius of curvature R72 of the image-side surface S13 of the seventh lens L7.

Example 2

An optical lens according to embodiment 2 of the present application is described below with reference to fig. 2. In this embodiment and the following embodiments, descriptions of parts similar to those of embodiment 1 will be omitted for the sake of brevity. Fig. 2 shows a schematic structural diagram of an optical lens according to embodiment 2 of the present application.

As shown in fig. 2, the optical lens includes, in order from the object side to the image side along the optical axis, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, and a seventh lens L7.

The first lens L1 is a meniscus lens with positive power, with the object side S1 being convex and the image side S2 being concave. The second lens L2 is a meniscus lens with positive power, with the object side S3 being convex and the image side S4 being concave. The third lens L3 is a biconcave lens with negative optical power, and both the object-side surface S6 and the image-side surface S7 are concave. The fourth lens L4 is a biconvex lens with positive optical power, and has both the object-side surface S7 and the image-side surface S8 convex. The fifth lens L5 is a biconvex lens with positive optical power, and has both the object-side surface S9 and the image-side surface S10 convex. The sixth lens L6 is a meniscus lens with negative power, and has a concave object-side surface S10 and a convex image-side surface S11. The seventh lens L7 is a meniscus lens with negative power, with the object side S12 being concave and the image side S13 being convex. The third lens L3 and the fourth lens L4 are cemented together to form a first cemented lens, and the fifth lens L5 and the sixth lens L6 are cemented together to form a second cemented lens.

In the optical lens of the present embodiment, a stop STO may be provided between, for example, the second lens L2 and the third lens L3 to improve the imaging quality. Optionally, the optical lens may further include a filter L8 having an object-side surface S14 and an image-side surface S15, and a protective lens L9 having an object-side surface S16 and an image-side surface S17. Filter L8 can be used to correct for color deviations. The protective lens L9 may be used to protect the image sensing chip on the imaging plane IMA. Light from the object passes through each of the surfaces S1 to S17 in sequence and is finally imaged on the imaging plane IMA.

Table 3 below shows a radius of curvature R, a thickness T, a refractive index Nd, and an abbe number Vd of each lens of the optical lens of example 2, where the radius of curvature R and the thickness T are both in units of millimeters (mm).

Flour mark	Radius of curvature R	Thickness T	Refractive index Nd	Abbe number Vd
					S1	45.6630	2.5000	1.90	31.3
S2	81.8969	0.5000
					S3	10.1062	2.3000	1.76	27.5
S4	65.4569	0.3000
					STO	All-round	1.0000
S6	-11.2671	1.2000	1.65	33.8
					S7	14.0572	3.0000	1.88	40.8
S8	-16.0289	0.1000
					S9	19.6034	3.5000	1.80	46.6
S10	-16.7524	2.0000	1.78	25.7
					S11	-195.5045	0.9720
S12	-4.9011	2.2500	1.76	27.5
					S13	-17.0876	0.5000
S14	All-round	0.5500	1.52	64.2
					S15	All-round	0.6313
S16	All-round	0.4000	1.52	64.2
					S17	All-round	0.1250
IMA	All-round

TABLE 3

In this embodiment, the object-side surface and the image-side surface of any one of the first lens to the seventh lens are spherical surfaces.

Table 4 below gives the combined focal length f34 of the third lens L3 and the fourth lens L4, the combined focal length f56 of the fifth lens L5 and the sixth lens L6, the entire group focal length f of the optical lens, and the total optical length TTL of the optical lens of embodiment 2.

Parameter(s)	f34(mm)	f56(mm)	f(mm)	TTL(mm)
					Numerical value	47.857	21.906	13.069	21.828

TABLE 4

In the present embodiment, f34/f 3.662 is satisfied between the combined focal length f34 of the third lens L3 and the fourth lens L4 of the optical lens and the entire group focal length f of the optical lens; f56/f is 1.676 between the combined focal length f56 of the fifth lens L5 and the sixth lens L6 and the entire group focal length f of the optical lens; the total optical length TTL of the optical lens and the whole group focal length f of the optical lens meet the condition that TTL/f is 1.670; R72/R71 ═ 3.486 between the radius of curvature R71 of the object-side surface S12 of the seventh lens L7 and the radius of curvature R72 of the image-side surface S13 of the seventh lens L7.

Example 3

An optical lens according to embodiment 3 of the present application is described below with reference to fig. 3. Fig. 3 shows a schematic structural diagram of an optical lens according to embodiment 3 of the present application.

As shown in fig. 3, the optical lens includes, in order from the object side to the image side along the optical axis, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, and a seventh lens L7.

The first lens L1 is a meniscus lens with positive power, with the object side S1 being convex and the image side S2 being concave. The second lens L2 is a meniscus lens with positive power, with the object side S3 being convex and the image side S4 being concave. The third lens L3 is a biconcave lens with negative optical power, and both the object-side surface S6 and the image-side surface S7 are concave. The fourth lens L4 is a biconvex lens with positive optical power, and has both the object-side surface S7 and the image-side surface S8 convex. The fifth lens L5 is a biconvex lens with positive optical power, and has both the object-side surface S9 and the image-side surface S10 convex. The sixth lens L6 is a meniscus lens with negative power, and has a concave object-side surface S10 and a convex image-side surface S11. The seventh lens L7 is a meniscus lens with negative power, with the object side S12 being concave and the image side S13 being convex. The third lens L3 and the fourth lens L4 are cemented together to form a first cemented lens, and the fifth lens L5 and the sixth lens L6 are cemented together to form a second cemented lens.

In the optical lens of the present embodiment, a stop STO may be provided between, for example, the second lens L2 and the third lens L3 to improve the imaging quality. Optionally, the optical lens may further include a filter L8 having an object-side surface S14 and an image-side surface S15, and a protective lens L9 having an object-side surface S16 and an image-side surface S17. Filter L8 can be used to correct for color deviations. The protective lens L9 may be used to protect the image sensing chip on the imaging plane IMA. Light from the object passes through each of the surfaces S1 to S17 in sequence and is finally imaged on the imaging plane IMA.

Table 5 below shows a radius of curvature R, a thickness T, a refractive index Nd, and an abbe number Vd of each lens of the optical lens of example 3, where the radius of curvature R and the thickness T are both in units of millimeters (mm).

TABLE 5

In this embodiment, the object-side surface and the image-side surface of any one of the first lens to the seventh lens are spherical surfaces.

Table 6 below gives the combined focal length f34 of the third lens L3 and the fourth lens L4, the combined focal length f56 of the fifth lens L5 and the sixth lens L6, the entire group focal length f of the optical lens, and the total optical length TTL of the optical lens of embodiment 3.

Parameter(s)	f34(mm)	f56(mm)	f(mm)	TTL(mm)
					Numerical value	58.946	17.195	13.078	22.000

TABLE 6

In the present embodiment, f34/f ═ 4.507 is satisfied between the combined focal length f34 of the third lens L3 and the fourth lens L4 of the optical lens and the entire group focal length f of the optical lens; f56/f is 1.315 between the combined focal length f56 of the fifth lens L5 and the sixth lens L6 and the whole group focal length f of the optical lens; the total optical length TTL of the optical lens and the whole group focal length f of the optical lens meet the condition that TTL/f is 1.682; R72/R71 ═ 4.382 between the radius of curvature R71 of the object-side surface S12 of the seventh lens L7 and the radius of curvature R72 of the image-side surface S13 of the seventh lens L7.

Example 4

An optical lens according to embodiment 4 of the present application is described below with reference to fig. 4. Fig. 4 shows a schematic structural diagram of an optical lens according to embodiment 4 of the present application.

As shown in fig. 4, the optical lens includes, in order from the object side to the image side along the optical axis, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, and a seventh lens L7.

The first lens L1 is a meniscus lens with negative power, with the object side S1 being convex and the image side S2 being concave. The second lens L2 is a meniscus lens with positive power, with the object side S3 being convex and the image side S4 being concave. The third lens L3 is a biconcave lens with negative optical power, and both the object-side surface S6 and the image-side surface S7 are concave. The fourth lens L4 is a biconvex lens with positive optical power, and has both the object-side surface S7 and the image-side surface S8 convex. The fifth lens L5 is a biconvex lens with positive optical power, and has both the object-side surface S9 and the image-side surface S10 convex. The sixth lens L6 is a meniscus lens with positive power, with the object side S10 being concave and the image side S11 being convex. The seventh lens L7 is a meniscus lens with negative power, with the object side S12 being concave and the image side S13 being convex. The third lens L3 and the fourth lens L4 are cemented together to form a first cemented lens, and the fifth lens L5 and the sixth lens L6 are cemented together to form a second cemented lens.

In the optical lens of the present embodiment, a stop STO may be provided between, for example, the second lens L2 and the third lens L3 to improve the imaging quality. Optionally, the optical lens may further include a filter L8 having an object-side surface S14 and an image-side surface S15, and a protective lens L9 having an object-side surface S16 and an image-side surface S17. Filter L8 can be used to correct for color deviations. The protective lens L9 may be used to protect the image sensing chip on the imaging plane IMA. Light from the object passes through each of the surfaces S1 to S17 in sequence and is finally imaged on the imaging plane IMA.

Table 7 shows a radius of curvature R, a thickness T, a refractive index Nd, and an abbe number Vd of each lens of the optical lens of example 4, where the radius of curvature R and the thickness T are both in units of millimeters (mm).

TABLE 7

In this embodiment, the object-side surface and the image-side surface of any one of the first lens to the seventh lens are spherical surfaces.

Table 8 below gives the combined focal length f34 of the third lens L3 and the fourth lens L4, the combined focal length f56 of the fifth lens L5 and the sixth lens L6, the entire group focal length f of the optical lens, and the total optical length TTL of the optical lens of embodiment 4.

Parameter(s)	f34(mm)	f56(mm)	f(mm)	TTL(mm)
					Numerical value	51.424	13.109	13.094	22.008

TABLE 8

In the present embodiment, f34/f 3.927 is satisfied between the combined focal length f34 of the third lens L3 and the fourth lens L4 of the optical lens and the entire group focal length f of the optical lens; f56/f is 1.001 between the combined focal length f56 of the fifth lens L5 and the sixth lens L6 and the whole group focal length f of the optical lens; the total optical length TTL of the optical lens and the whole group focal length f of the optical lens satisfy that TTL/f is 1.681; R72/R71 ═ 6.378 between the radius of curvature R71 of the object-side surface S12 of the seventh lens L7 and the radius of curvature R72 of the image-side surface S13 of the seventh lens L7.

Example 5

An optical lens according to embodiment 5 of the present application is described below with reference to fig. 5. Fig. 5 shows a schematic structural diagram of an optical lens according to embodiment 5 of the present application.

As shown in fig. 5, the optical lens includes, in order from the object side to the image side along the optical axis, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, and a seventh lens L7.

The first lens L1 is a meniscus lens with positive power, with the object side S1 being convex and the image side S2 being concave. The second lens L2 is a meniscus lens with positive power, with the object side S3 being convex and the image side S4 being concave. The third lens L3 is a biconcave lens with negative optical power, and both the object-side surface S6 and the image-side surface S7 are concave. The fourth lens L4 is a biconvex lens with positive optical power, and has both the object-side surface S7 and the image-side surface S8 convex. The fifth lens L5 is a biconvex lens with positive optical power, and has both the object-side surface S9 and the image-side surface S10 convex. The sixth lens L6 is a biconcave lens with negative optical power, and has concave object-side surface S10 and concave image-side surface S11. The seventh lens L7 is a meniscus lens with positive power, with the object side S12 being concave and the image side S13 being convex. The third lens L3 and the fourth lens L4 are cemented together to form a first cemented lens, and the fifth lens L5 and the sixth lens L6 are cemented together to form a second cemented lens.

In the optical lens of the present embodiment, a stop STO may be provided between, for example, the second lens L2 and the third lens L3 to improve the imaging quality. Optionally, the optical lens may further include a filter L8 having an object-side surface S14 and an image-side surface S15, and a protective lens L9 having an object-side surface S16 and an image-side surface S17. Filter L8 can be used to correct for color deviations. The protective lens L9 may be used to protect the image sensing chip on the imaging plane IMA. Light from the object passes through each of the surfaces S1 to S17 in sequence and is finally imaged on the imaging plane IMA.

Table 9 shows a radius of curvature R, a thickness T, a refractive index Nd, and an abbe number Vd of each lens of the optical lens of example 5, where the radius of curvature R and the thickness T are both in units of millimeters (mm).

TABLE 9

In this embodiment, the object-side surface and the image-side surface of any one of the first lens to the seventh lens are spherical surfaces.

Table 10 below gives the combined focal length f34 of the third lens L3 and the fourth lens L4, the combined focal length f56 of the fifth lens L5 and the sixth lens L6, the entire group focal length f of the optical lens, and the total optical length TTL of the optical lens of example 5.

Parameter(s)	f34(mm)	f56(mm)	f(mm)	TTL(mm)
					Numerical value	60.022	25.050	14.039	32.302

Watch 10

In the present embodiment, f34/f 4.275 is satisfied between the combined focal length f34 of the third lens L3 and the fourth lens L4 of the optical lens and the entire group focal length f of the optical lens; f56/f is 1.784 between the combined focal length f56 of the fifth lens L5 and the sixth lens L6 and the entire group focal length f of the optical lens; the total optical length TTL of the optical lens and the whole group focal length f of the optical lens satisfy that TTL/f is 2.301; the radius of curvature R71 of the object-side surface S12 of the seventh lens L7 and the radius of curvature R72 of the image-side surface S13 of the seventh lens L7 satisfy that R72/R71 is 0.483

In summary, examples 1 to 5 each satisfy the relationship shown in table 11 below.

Conditional expression (A) example	1	2	3	4	5
						f34/f	3.558	3.662	4.507	3.927	4.275
f56/f	1.423	1.676	1.315	1.001	1.784
						TTL/f	1.694	1.670	1.682	1.681	2.301
R72/R71	4.910	3.486	4.382	6.378	0.483

TABLE 11

The above description is only a preferred embodiment of the application and is illustrative of the principles of the technology employed. It will be appreciated by a person skilled in the art that the scope of the invention as referred to in the present application is not limited to the embodiments with a specific combination of the above-mentioned features, but also covers other embodiments with any combination of the above-mentioned features or their equivalents without departing from the inventive concept. For example, the above features may be replaced with (but not limited to) features having similar functions disclosed in the present application.

Claims (19)

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 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 positive focal power, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface;

the third lens and the fourth lens are combined into a first cemented lens, wherein the fourth lens has positive focal power, and the third lens has negative focal power;

the fifth lens and the sixth lens are glued to form a second cemented lens; and

the object side surface of the seventh lens is a concave surface, the image side surface of the seventh lens is a convex surface,

wherein the number of lenses having a power in the optical lens is seven,

wherein a combined focal length f34 of the third lens and the fourth lens and a whole group focal length f of the optical lens satisfy 2 ≦ f34/f ≦ 6.

2. An optical lens as claimed in claim 1, characterized in that the first lens has a negative optical power.

3. An optical lens as claimed in claim 1, characterized in that the first lens has a positive optical power.

4. An optical lens according to claim 1,

the object side surface and the image side surface of the third lens are both concave surfaces; and

the object side surface and the image side surface of the fourth lens are convex surfaces.

5. An optical lens according to claim 1,

the fifth lens in the second cemented lens has positive focal power, and both the object-side surface and the image-side surface of the fifth lens are convex surfaces; and

the object side surface of the sixth lens in the second cemented lens is a concave surface.

6. An optical lens barrel according to any one of claims 1 to 5, wherein a radius of curvature R71 of an object side surface of the seventh lens and a radius of curvature R72 of an image side surface of the seventh lens satisfy 0 ≦ R72/R71 ≦ 8.

7. An optical lens according to any one of claims 1 to 5, characterized in that 0.2 ≦ f56/f ≦ 2.5 between the combined focal length f56 of the fifth lens and the sixth lens and the entire group focal length f of the optical lens.

8. An optical lens according to any one of claims 1 to 5, wherein an optical total length TTL of the optical lens and a whole group focal length f of the optical lens satisfy TTL/f ≦ 2.8.

9. 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 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 positive focal power, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface;

the third lens and the fourth lens are combined into a first cemented lens, wherein the fourth lens has positive focal power, and the third lens has negative focal power;

the fifth lens and the sixth lens are glued to form a second cemented lens; and

the object side surface of the seventh lens is a concave surface, the image side surface of the seventh lens is a convex surface,

wherein the number of lenses having a power in the optical lens is seven,

wherein a curvature radius R71 of an object side surface of the seventh lens and a curvature radius R72 of an image side surface of the seventh lens satisfy 0 ≦ R72/R71 ≦ 8.

10. 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 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 positive focal power, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface;

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

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

the object side surface of the sixth lens is a concave surface;

the object side surface of the seventh lens is a concave surface, and the image side surface of the seventh lens is a convex surface; and

the total optical length TTL of the optical lens and the whole group of focal length f of the optical lens meet the condition that TTL/f is less than or equal to 2.8,

wherein the number of lenses having a power in the optical lens is seven,

wherein a curvature radius R71 of an object side surface of the seventh lens and a curvature radius R72 of an image side surface of the seventh lens satisfy 0 ≦ R72/R71 ≦ 8.

11. An optical lens as claimed in claim 10, characterized in that the first lens has a negative optical power.

12. An optical lens as claimed in claim 10, characterized in that the first lens has a positive optical power.

13. An optical lens according to claim 10, wherein the third lens is cemented with the fourth lens to form a first cemented lens.

14. An optical lens according to claim 10, wherein the fifth lens is cemented with the sixth lens to form a second cemented lens.

15. An optical lens barrel according to claim 14, wherein the image side surface of the sixth lens element is convex.

16. An optical lens barrel according to claim 14, wherein the image side surface of the sixth lens element is concave.

17. An optical lens according to any one of claims 10 to 16, characterized in that a combined focal length f34 of the third lens and the fourth lens and a whole group focal length f of the optical lens satisfy 2 ≦ f34/f ≦ 6.

18. An optical lens according to any one of claims 10 to 16, characterized in that a combined focal length f56 of the fifth lens and the sixth lens and a whole group focal length f of the optical lens satisfy 0.2 ≦ f56/f ≦ 2.5.

19. 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 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 positive focal power, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface;

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

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

the object side surface of the sixth lens is a concave surface;

the object side surface of the seventh lens is a concave surface, and the image side surface of the seventh lens is a convex surface; and

the total optical length TTL of the optical lens and the whole group of focal length f of the optical lens meet the condition that TTL/f is less than or equal to 2.8,

wherein the number of lenses having a power in the optical lens is seven,

wherein a combined focal length f34 of the third lens and the fourth lens and a whole group focal length f of the optical lens satisfy 2 ≦ f34/f ≦ 6.

Images