TWI407184B - Six-piece imaging lens module - Google Patents

Abstract

A six-piece imaging lens module includes a first lens, a fixed aperture stop, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens sequentially disposed between an object and an image. The first lens is a negative meniscus, and the first lens has a convex surface disposed toward the object. The second lens is a positive lens, and the second lens has a convex surface disposed toward the image. The third lens is a positive lens, and the third lens has a convex surface disposed toward the object. The fourth lens is a negative lens, and the fourth lens has a concave surface disposed toward the image. The fifth lens is a positive lens, and the fifth lens has a convex surface disposed toward the image. The fourth and the fifth lenses are bonded to form a composite lens. The sixth lens has a convex surface toward the object near the axis.

Description

Six-piece imaging lens set

The invention relates to the field of optical lenses, in particular to a six-piece imaging lens set with large aperture and high resolution.

At present, the use of optical lenses in the field of digital imaging is increasing day by day, especially for digital telephones such as mobile phone products, game consoles, PC CAM, DSC or DVC. With the development of the industry and the market trend, the above-mentioned digital carriers have been developed toward miniaturization, that is, the structure is light, thin, high-performance and economies of scale. Therefore, the lens group in the carrier needs to be relatively small. Therefore, the development of the imaging lens group has also been improved and innovated with this trend, and having a high-quality imaging lens group is a key component of the manufacturer's competition in the industry.

However, in the prior art, a lens group using three or four lenses is not suitable for a high-order lens group because the chromatic aberration and the aberration are too large to obtain high image quality; if high image quality is ensured The optical length will be longer, which is in the small electronic carrier, and it is impossible to achieve both space and quality due to space constraints.

In addition, China Patent Publication No. 200923467 discloses an imaging lens group composed of five lenses, but how to further improve the image quality is still the direction of the industry.

The main object of the present invention is to provide a six-piece imaging lens set that enhances image quality under conditions of large aperture and large picture angle.

In order to achieve the above, the imaging lens assembly of the present invention comprises a fixed diaphragm and an optical group, wherein the optical group consists of a first lens, a second lens, a third lens, a fourth lens, and a first lens. The fifth lens and the sixth lens are arranged in the order from the object side to the image side: the first lens is a lens having a negative refractive power meniscus and a convex surface toward the object side, and at least one side thereof is non- The second lens is a lens having a positive refractive power and is convex toward the image side, and at least one side thereof is aspherical; the third lens is a lens having a positive refractive power and a convex surface toward the object side. And the at least one surface is an aspherical surface; the fourth lens is a lens having a negative refractive power and is concave toward the image side; the fifth lens is a lens having a positive refractive power and is convex toward the image side, and the fourth and fifth lenses are The lenses are bonded to each other to form a composite lens; the sixth lens is a lens that is convex toward the object side near the optical axis, and at least one side thereof is aspherical.

As for the structural design of the above-mentioned imaging lens group, the following description will be given in conjunction with the related drawings and the embodiments described later.

The present invention adopts the relevant embodiments and is illustrated by the drawings. The numerical changes of the embodiments of the present invention are all designed, and even if other products having the same structure use different values, they should belong to the protection scope of the present invention. First described.

Referring to Figures 1, 2 and the six-piece imaging lens set shown in the second embodiment, the present invention can be applied to a light, thin and short digital carrier. In an embodiment, the imaging lens set includes a fixed diaphragm 1 and an optical group consisting of first, second, third, fourth, fifth, and sixth lenses L1, L2, L3, and L4. And L5 and L6 are arranged in the order from the object side A to the image side B: the first lens L1 is a lens having a negative refractive power meniscus and is convex toward the object side, and at least one side thereof is non- a spherical surface; the second lens L2 is a lens having a positive refractive power and is convex toward the image side, and at least one side thereof is aspherical; the third lens L3 is a lens having a positive refractive power and facing the object side a convex surface, and at least one surface thereof is aspherical; the fourth lens L4 is a lens having a negative refractive power and is concave toward the image side; the fifth lens L5 is a lens having a positive refractive power and is convex toward the image side, and The fourth and fifth lenses L4 and L5 are bonded to each other to form a composite lens. The sixth lens L6 is a lens that is convex toward the object side near the optical axis, and at least one side thereof is aspherical.

The system of the present invention is an optical group composed of six lenses, and the first flat plate glass 2 located behind the sixth lens L6 has the function of filtering infrared rays; and another second flat plate is further disposed before the image side B. The glass 3, the second flat plate glass 3 has the function of protecting the photosensitive element, and the first and second flat plate glasses 2 and 3 can be increased or decreased according to the image sensor with different package structure to achieve better image quality. In addition to the photosensitive element configured on the side B, CCD or CMOS can be selected according to actual needs.

In addition, the difference graph of the present invention is shown in FIG. 1A and FIG. 2A by the non-point difference, the distortion, and the spherical aberration. Regardless of the difference map, the data of the d line is used instead of the point difference. It is about the data of S image (SAGITTAL) and the data of TANGENTIAL, and it is shown in the figure; and it is clear from the difference diagram that the compensation of the invention is the result of the complete simulation design. There is no problem in use.

Referring to FIG. 1B and FIG. 2B of the present invention, the aspherical data of the second embodiment of the present invention, the uppermost data is the code of each lens of the optical group of the present invention: F. No.: the F value is in optical design , representing the brightness parameter, wherein the smaller the F value, the higher the brightness; the angle of view: 2ω; the focus distance f: f is the combined focus distance (mm) of the optical group.

The lower 2, 3, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18 are the number of lens surface numbers in the order of the object side; the number 2, 3 The two sides of the first lens L1, the surface numbers 6, 7 are two sides of the second lens L2, the face numbers 8, 9 are two sides of the third lens L3, and the face numbers 10, 11, 12 are the fourth The lens L4 and the fifth lens L5 are bonded to form a mirror surface of the composite lens, and the surface numbers 13 and 14 are two sides of the sixth lens L6, and the first flat plate glass 2 and the second flat plate are respectively 15 , 16 and 17 and 18 . Two sides of the glass 3.

In order to improve the deficiencies of the conventional imaging lens group, the lens group of the present invention preferably satisfies the following conditions: First, the focal length values of the first lens L1 and the second lens L2 must be controlled:

0.6<|f1|/|f2|<2.0,

Where f1 is the focal length value of the first lens L1, and f2 is the focal length value of the second lens L2; then, the focal length value between the second and third lenses L2 and L3 must be controlled to be compatible with the first and second lenses L1, L2 The focal lengths cooperate with each other:

0.3<|f2|/|f3|<1.0,

Where f2 is the focal length value of the second lens L2, and f3 is the focal length value of the third lens L3; furthermore, it is also necessary to control the focal length value of the third lens L3 and the focal length ratio of the fourth and fifth lenses L4, L5:

0<|f3|/|f45|<0.6,

Where f3 is the focal length value of the third lens, f45 is the composite focal length value of the fourth and fifth lenses; in addition, the focal length ratio of the fourth and fifth lenses L4, L5 and the focal length ratio of the sixth lens L6 are also controlled:

1.5<|f45|/|f6|<7,

Where f45 is the composite focal length value of the fourth lens and the fifth lens, and f6 is the focal length value of the sixth lens; in addition, in order to achieve high quality imaging, it is necessary to control the distance from the first face of the first lens to the imaging surface :

0.1<|f/TL|<0.6;

Where TL is the distance from the first side of the first lens to the imaging surface, and f is the focal length value of the entire lens group.

If the above optical mode is satisfied, the six-piece imaging lens set can have better image quality. On the contrary, if the optical data value range is less than or exceeds, the performance and resolution of the six-piece imaging lens group are low, and Problems such as insufficient yield.

In addition, in some lenses of the optical group of the present invention, at least one side may have an aspherical shape, and the aspherical surface shape must satisfy the following formula:

Where z is the position value with reference to the surface apex at the height h position along the optical axis; k is the cone constant metric; c is the reciprocal of the radius of curvature; A, B, C, D, E, G,... ...is a high-order aspheric coefficient.

In summary, the present invention uses the fourth and fifth lenses L4 and L5 to adhere to each other, so that the imaging chromatic aberration can be effectively controlled, and the color is more saturated, and the composite of the fourth and fifth lenses is further combined. A third lens L3 is added in front of the lens, which can effectively improve the image quality under the condition of large aperture and large angle of painting, which is beneficial to the miniaturization of digital photographic carriers, high pixel demand, and easy manufacturing in various aspects. A novel and practical design that is both practical and easy to use, and filed a patent application in accordance with the law, in view of the early approval of the patent by the bureau, it is really sensible.

A. . . Object side

B. . . Image side

1. . . Light bar

2. . . First flat plate glass

3. . . Second flat plate glass

L1. . . First lens

L2. . . Second lens

L3. . . Third lens

L4. . . Fourth lens

L5. . . Fifth lens

L6. . . Sixth lens

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a view showing the composition of a lens of a first embodiment of the present invention.

Fig. 1A is a diagram showing the difference of the first embodiment of the present invention.

Fig. 1B is a schematic diagram showing optical characteristic data and aspherical coefficient data of the first embodiment of the present invention.

Figure 2 is a view showing the composition of a lens of a second embodiment of the present invention.

Fig. 2A is a diagram showing the difference of the second embodiment of the present invention.

2B is a schematic diagram of optical characteristic data and aspherical coefficient data of a second embodiment of the present invention.

A. . . Object side

B. . . Image side

1. . . Light bar

2. . . First flat plate glass

3. . . Second flat plate glass

L1. . . First lens

L2. . . Second lens

L3. . . Third lens

L4. . . Fourth lens

L5. . . Fifth lens

L6. . . Sixth lens

Claims (10)

A six-piece imaging lens set includes a fixed diaphragm and an optical group, wherein the optical group consists of a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a The sixth lens is composed of an order from the object side to the image side: the first lens is a lens having a negative refractive power meniscus and is convex toward the object side, and at least one side thereof is aspherical; the light The second lens is a lens having a positive refractive power and is convex toward the image side, and at least one side thereof is aspherical; the third lens is a lens having a positive refractive power and a convex surface toward the object side, and at least one side thereof Is aspherical; the fourth lens is a lens having a negative refractive power and is concave toward the image side; the fifth lens is a lens having a positive refractive power and is convex toward the image side, and the fourth and fifth lens systems are bonded to each other Forming a composite lens; the sixth lens is a lens that is convex toward the object side near the optical axis, and at least one side thereof is aspherical. The six-piece imaging lens set described in claim 1 is characterized by the following condition: 0.6<|f1|/|f2|<2.0, where f1 is the focal length value of the first lens, and f2 is the second lens Focal length value. For example, the six-piece imaging lens set described in claim 1 satisfies the following condition: 0.3<|f2|/|f3|<1.0, where f2 is the focal length value of the second lens, and f3 is the third lens Focal length value. For example, the six-piece imaging lens set described in claim 2 satisfies the following condition: 0.3<|f2|/|f3|<1.0, where f2 is the focal length value of the second lens, and f3 is the third lens Focal length value. For example, the six-piece imaging lens set described in claim 1 satisfies the following condition: 0<|f3|/|f45|<0.6, where f3 is the focal length value of the third lens, and f45 is the fourth and the The composite focal length value of the five lenses. For example, the six-piece imaging lens set described in claim 4 satisfies the following condition: 0<|f3|/|f45|<0.6, where f3 is the focal length value of the third lens, and f45 is the fourth, The composite focal length value of the five lenses. For example, the six-piece imaging lens set described in claim 1 satisfies the following condition: 1.5<|f45|/|f6|<7, where f45 is the composite focal length value of the fourth lens and the fifth lens, f6 It is the focal length value of the sixth lens. For example, the six-piece imaging lens set described in claim 6 satisfies the following condition: 1.5<|f45|/|f6|<7, where f45 is the composite focal length value of the fourth lens and the fifth lens, f6 It is the focal length value of the sixth lens. The six-piece imaging lens set described in claim 1 is characterized by the following condition: 0.1<|f/TL|<0.6, wherein TL is the distance between the first face of the first lens and the imaging surface, f The focal length value for the entire lens set. The six-piece imaging lens set according to claim 1, wherein the aspherical surface shape satisfies the following formula: Where z is the position value with reference to the surface apex at the height h position along the optical axis; k is the cone constant metric; c is the reciprocal of the radius of curvature; A, B, C, D, E, G,... ...is a high-order aspheric coefficient.