CN202330847U - Image-forming lens set - Google Patents

Abstract

The utility model discloses an image-forming lens set. The image-forming lens set comprises a fixed diaphragm and an optical group, wherein the optical group comprises a first lens, a second lens, a third lens and a fourth lens. The lenses are arranged from an object side to an image side in sequence as follows: the first lens has a meniscus shaped lens with positive refractive power and a concave surface towards the image side; the second lens has a meniscus shaped lens with negative refractive power and a concave surface towards the image side; the third lens has a meniscus shaped lens with positive refractive power and a convex surface towards the image side; and the fourth lens has a concave surface towards the object side. The diaphragm and the lenses of the image-forming lens set are arranged, so that the optical length is greatly shortened, higher pixel output requirements are satisfied, and a four-piece image-forming lens set with the characteristic of simple manufacturing and high yield is manufactured.

Description

The imaging lens set

Technical field

The utility model belongs to field of optical lens, particularly a kind of imaging lens set that is installed on the tool four-piece type in the small image extraction device.

Background technology

Press simplicity of design, the height of use, and interconnectivity easily; To be the emphasis of following various electric consumers development, and electric consumers can be strengthened its interconnectivity for asking recently, then digital carrier and optical lens is mutually combined; Let digital carrier possess the multimedia function that shooting or instant video are watched; Wherein, especially with carriers such as modal 3C Product-mobile phone, Webcam or NB, optical lens has almost become the market mainstream and has been equipped with; Yet along with light, thin, short, the little trend of each electronic product trend, the related optical lens that makes also needs further to promote its lightening, as can significantly to compress in the space safely smoothly slimming carrier; Except light, thin, short, little demand emphasis; The consumer is for interior pixel and the image quality that is built in the optical lens in the carrier; Also be to select one of important consideration factor of buying in digital carrier; The also therefore mobile phone of two mega pixels of existing market main flow can't satisfy young consumption group already.

But the documents and materials of the at present domestic relevant four-piece type imaging eyeglass of sight show, because the design of the 4th eyeglass dipped beam shaft position; For one side (towards the thing side) at least is convex surface design; Cause the order city to carry the digital carrier of this four-piece type imaging lens set, for fear of whole optical mirror slip, and at least one end of the 4th eyeglass dipped beam axle designs for convex surface; So that this four-piece type imaging lens; No doubt can the output image quality be pushed into more than two mega pixels, but whole image quality, color saturation and optical length etc. but can't be taken into account;

Moreover; The four-piece type imaging lens set that relevant previous document is disclosed, the design of whole optical mirror slip is recessed design for protruding one side simultaneously for fear of the 4th eyeglass dipped beam shaft position often; Then be prone to cause the optical length of camera lens effectively to shorten and to make degree of difficulty higher; Nature can't meet the market competition demand, also causes the fine ratio of product of four-piece type imaging lens set simultaneously, slowly can't reach the target of hoping for of industry.

Therefore, the four-piece type optical lens group that how to have high image quality is an important topic, and the utility model provides like hereinafter, specifies like said innovative imaging lens set.

The utility model content

The purpose of the utility model provides a kind of imaging lens set; It replaces original spheric glass to reduce the eyeglass number with importing aspheric design easily; Simultaneously can improve spherical aberration; Compare the known glass eyeglass and have advantages such as thin, little, light, and this eyeglass all adopts plastic cement material, be beneficial to and reduce manufacturing cost and overhead cost.

A time purpose of the utility model provides a kind of imaging lens set; Utilize this first eyeglass towards the picture side for concave surface and the 4th eyeglass towards the aspherical mirror of thing side for concave surface; Make and on making, reduce the influence of systematic error sensitivity easily, and promote the product yield than known technology; And the eyeglass arrangement mode and the configuration of the utility model make optical full length shorter, can supply this lens set that enough configuration spaces are arranged.

Make the high-quality imaging lens set that contrast improves and yield is produced in lifting of imaging system, it utilizes aspheric lens design and forms.Therefore for elevator system usefulness, our eyeglass selective optical plastic cement utilizes the optical design software, with each lens aspherisation as lens material.Its objective is that the degree of freedom that makes system design increases, is beneficial to the optimization whole optical system, to meet its optical specification demand, makes camera lens in the volume production process, can promote yield, and good image quality is arranged.

For realizing above-mentioned purpose, the utility model is taked following technical scheme:

The utility model proposes a kind of imaging lens set, and it includes a fixed light hurdle and an optical group, and this optical group comprises first, second, third, fourth eyeglass, and its arrangement mode from thing side to the order as side is:

This first eyeglass has the positive refractive power meniscus shaped lens and towards being concave surface as side; It has at least one side to be aspheric surface again;

This light hurdle;

This second eyeglass has the negative refractive power meniscus shaped lens and towards being concave surface as side; It has at least one side to be aspheric surface again;

This prismatic glasses has the positive refractive power meniscus shaped lens and towards being convex surface as side; It has at least one side to be aspheric surface again;

The 4th eyeglass, having towards the thing side is concave surface; It has at least one side to be aspheric surface again.

Described imaging lens set meets the following conditions:

0.3＜|f1|/|f2|＜0.8，

Wherein f1 is the focal length value of first eyeglass, and f2 is the focal length value of second eyeglass.

Described imaging lens set meets the following conditions:

0.8＜|f3|/|f4|＜1.3，

Wherein f3 is the focal length value of prismatic glasses, and f4 is the focal length of the 4th eyeglass.

Described imaging lens set meets the following conditions:

|f234|/|f|＜2，

Wherein f234 is the synthetic focal length value of second eyeglass, prismatic glasses and the 4th eyeglass, | f| is the focal length value of whole lens set.

Described imaging lens set meets the following conditions:

N2＞1.57，

V2＜40，

Wherein N2 is the refractive index of second eyeglass, and V2 is the Abbe coefficient of second eyeglass.

Said aspheric type satisfies formula:

$z=\frac{{\mathrm{<figure-callout\; id="2"\; label="ch"\; filenames="HDA0000110612780000011.png,HDA0000110612780000031.png"\; state="\{\{state\}\}">ch</figure-callout>}}^2}{1+{[1-(k+1)c^2{h}^2]}^{0.5}}+{\mathrm{<figure-callout\; id="4"\; label="Ah"\; filenames="HDA0000110612780000011.png,HDA0000110612780000031.png"\; state="\{\{state\}\}">Ah</figure-callout>}}^4+{\mathrm{Bh}}^6+{\mathrm{Ch}}^8+{\mathrm{Dh}}^{10}+{\mathrm{Eh}}^{12}+{\mathrm{Gh}}^{14}+..........$

Wherein z be along optical axis direction highly for the position of h with surface vertices positional value for referencial use; K is awl normal manner amount; C is the inverse of radius-of-curvature; A, B, C, D, E, G ... Be the high-order asphericity coefficient.

As for, the structural design of above-mentioned imaging lens set, please cooperate now relevant indicators and after the embodiment explanation stated.

The beneficial effect of the utility model is: the utility model replaces original spheric glass to reduce the eyeglass number with importing aspheric design easily; Simultaneously can improve spherical aberration; Compare the known glass eyeglass and have advantages such as thin, little, light; And this eyeglass all adopts plastic cement material, is beneficial to reduce manufacturing cost and overhead cost.Utilize this first eyeglass towards the picture side for concave surface and the 4th eyeglass towards the aspherical mirror of thing side for concave surface, make and on making, reduce the influence of systematic error sensitivity easily, and lifting product yield than known technology; And the eyeglass arrangement mode and the configuration of the utility model make optical full length shorter, can supply this lens set that enough configuration spaces are arranged.

Description of drawings

Fig. 1 is the eyeglass composition diagram of first embodiment of the utility model imaging lens set.

Figure 1A is the receipts difference figure of first embodiment of the utility model imaging lens set.

Fig. 2 is the eyeglass composition diagram of second embodiment of the utility model imaging lens set.

Fig. 2 A is the receipts difference figure of second embodiment of the utility model imaging lens set.

Drawing reference numeral: A: thing side; 1: the light hurdle; 3: the second plane sheet glass; L2: second eyeglass; L4: the 4th eyeglass; B: as side; 2: the first plane sheet glass; L1: first eyeglass; L3: prismatic glasses.

Embodiment

The utility model adopt relevant suitable embodiment and with graphic as explanation; Fig. 1 is the eyeglass composition diagram of the utility model first embodiment; And the receipts difference figure of embodiment is Figure 1A, sees also Figure 1A, and the numerical value change of each embodiment of the utility model all belongs to designing institute and gets; Even use the product of different numerical value, same structure must belong to the protection category of the utility model, state clearly in advance at this.

See also four-piece type lens set shown in Figure 1; The utility model is a kind of imaging lens set, in order to be installed on the compact digital carrier, in an embodiment; This imaging lens set is along optical axis; Begin to include in regular turn a fixed light hurdle 1 and an optical group from thing side A, this optical group comprises first, second, third, fourth eyeglass L1, L2, L3, L4, and its arrangement mode from thing side A to the order as side B is:

This first eyeglass L1 has the positive refractive power meniscus shaped lens and towards being concave surface as side B; It has at least one side to be aspheric surface again;

This light hurdle 1;

This second eyeglass L2 has the negative refractive power meniscus shaped lens and towards being concave surface as side B; It has at least one side to be aspheric surface again;

This prismatic glasses L3 has the positive refractive power meniscus shaped lens and towards being convex surface as side B; It has at least one side to be aspheric surface again;

The 4th eyeglass L4, having towards thing side A is concave surface; It has at least one side to be sphere again.

Aforementioned the utility model system promptly is the optical group that is made up of four pieces of eyeglasses, and is positioned at the first plane sheet glass 2 at the 4th eyeglass L4 rear, has the ultrared effect of filter; Before as side B, also establish one second plane sheet glass 3 in addition again; This second plane sheet glass 3 has the effect of protection photo-sensitive cell; This first, second plane sheet glass 2 and 3 can increase, subtract according to joining the CIS of fitting different encapsulating structures, reaches better image quality; At the photo-sensitive cell of picture side B place's configuration, then can select CCD or CMOS etc. in addition according to actual demand.

The characteristics of this imaging lens set are that eyeglass is by the plastic cement material formed thereby; Therefore can reduce material uses and managerial cost; Also appear because of using plastic material that eyeglass is led with non-spherical structure easily; Utilize lens to be aspherical lens, it is higher and and then be reduced to the imaging lens set that can reach better quality as required eyeglass sheet number to reach resolving power.

In addition; The receipts difference figure of the utility model with non-check and accept poor, distort to receive difference and sphere receive poor; Shown in Figure 1A, Fig. 2 A; No matter which kind of receives difference figure all is the data information about the d line, is to follow about T image planes (TANGENTIAL) data information about the data information of S image planes (SAGITAL) but not check and accept difference, and it is done the signal performance; And can know and know that the receipts difference revisal of the utility model all is complete board design gained, in practicality, has had no problem by receiving difference figure.

Table 1

Focal length: f = 3.679mm

(F?NO.)：F?2.8

angle: 2 ω=63 °

Table 2

Focal length: f = 4.027mm

(F?NO.)：F?2.8

angle: 2 ω=58.3 °

Sphere data data, the top data are the code name of each eyeglass set of data of the utility model optical group:

F.No.～this F value when optical design, represent luminance parameter, wherein the F value little expression luminance brightness that heals is higher.

Draw angle～2 ω.

Focal length～f; F is the synthetic focal length (mm) of optical group, below the 1,2,4,5,6,7,8,9,10,11,12, the 13rd, and the lens face numerical table that object side rises in regular turn shows; Face number number 1.2. is two of R1, the R2 of the first eyeglass L1; Face number number 4.5. is two of R1, the R2 of the second eyeglass L2; Face number number 6.7. is two of R1, the R2 of prismatic glasses L3; 8.9. be two of R1, the R2 of the 4th eyeglass L4,10.11.12.13. is the first plane sheet glass 2 and the second plane sheet glass 3 two.

The utility model is to ask the shortcoming that can improve known four lens set; Therefore at the first eyeglass L1 towards being that concave surface, the 4th eyeglass L4 then are concave surface at thing side A face as side B; And the focal length value of the focal length value of the focal length value of imaging focal length, prismatic glasses L3 and the 4th eyeglass L4 through the control first eyeglass L1 and the second eyeglass L2 and second and third, four eyeglass L2, L3, L4 and first, second, third and fourth eyeglass L1, L2, L3, the whole lens set of L4; Therefore; Reach the optimal imaging quality for asking, the utility model must meet the following conditions:

At first, because of the first eyeglass L1 is one towards being concave surface as side B, and the second eyeglass L2 is towards being concave surface as side B, makes the focal length value of the control first eyeglass L1 and the second eyeglass L2 earlier:

0.3＜|f1|/|f2|＜0.8，

Wherein f1 is the focal length value of the first eyeglass L1, and f2 is the focal length value of the second eyeglass L2;

Secondly, prismatic glasses L3 is towards being convex surface as side B, and the 4th minute surface L4 is a concave surface towards thing side A, and the focal length value between therefore also must control two eyeglasses could cooperatively interact with the focal length of first and second eyeglass L1, L2:

0.8＜|f3|/|f4|＜1.3，

Wherein f3 is the focal length value of prismatic glasses L3, and f4 is the focal length of the 4th eyeglass L4;

Then; The first eyeglass L1 is towards being concave surface as side B; The second eyeglass L2 is towards being concave surface as side B; Prismatic glasses L3 is towards being convex surface as side B, and the 4th minute surface L4 is a concave surface towards thing side A, therefore also must control second and third, the focal length value of the focal length value of four eyeglass L2, L3, L4 and first, second, third and fourth eyeglass L1, L2, L3, the whole lens set of L4:

|f234|/|f|＜2，

Wherein f234 is the synthetic focal length value of the second eyeglass L2, prismatic glasses L3 and the 4th eyeglass L4, | f| is the focal length value of whole lens set;

In addition, make to reach high-quality imaging, and must control its refractive index for asking:

N2＞1.57，

V2＜40

Wherein N2 is the refractive index of the second eyeglass L2, and V2 is the Abbe coefficient (Abbe number) of the second eyeglass L2;

Satisfy above-mentioned optical profile type; Then can make four-piece type imaging lens set, meet high pixel output demand, the resolving power of camera lens also has the lifting of explicitly; Otherwise; If less than or exceed the data value range of above-mentioned optical profile type, then can cause performance, the resolving power of four-piece type imaging lens set low, and problem such as yield deficiency.

In addition, each eyeglass of the utility model optical group, because of the two sides all can be aspherical shape, this aspheric type must satisfy formula:

$z=\frac{{\mathrm{<figure-callout\; id="2"\; label="ch"\; filenames="HDA0000110612780000011.png,HDA0000110612780000031.png"\; state="\{\{state\}\}">ch</figure-callout>}}^2}{1+{[1-(k+1)c^2{h}^2]}^{0.5}}+{\mathrm{<figure-callout\; id="4"\; label="Ah"\; filenames="HDA0000110612780000011.png,HDA0000110612780000031.png"\; state="\{\{state\}\}">Ah</figure-callout>}}^4+{\mathrm{Bh}}^6+{\mathrm{Ch}}^8+{\mathrm{Dh}}^{10}+{\mathrm{Eh}}^{12}+{\mathrm{Gh}}^{14}+..........$

Wherein z be along optical axis direction highly for the position of h with surface vertices positional value for referencial use; K is awl normal manner amount; C is the inverse of radius-of-curvature; A, B, C, D, E, G ... Be the high-order asphericity coefficient.

The utility model is in the most especially in: through the first eyeglass L1 second and is concave surface near near optical axis; And be the bi-concave novel designs near the 4th eyeglass L4 R1, R2 two sides dipped beam axle; Can effectively be suppressed to picture lens set optical length (TL), satisfy narrow space assembling effect lighter, the digital carrier of thinning; Moreover; More can satisfy the high image quality output demand of digital carrier (like the mobile phone camera), push the photography pixel of digital carrier to three hundred ten thousand to lift, even the output demand of higher pixel; And satisfy under the high pixel condition, more have the lifting of high image quality and color saturation concurrently; More prior; Be that through the first eyeglass L1 second is near adopting the bi-concave innovative design for R1, the R2 two sides dipped beam axle place of concave surface and the 4th eyeglass L4 near the optical axis; More can let the lens optical performance boost, reach the industry new standard of high fine ratio of product indirectly, to satisfy the market competition benefit.

Claims (6)

1. an imaging lens set is characterized in that it includes a fixed light hurdle and an optical group, and this optical group comprises first, second, third, fourth eyeglass, and its arrangement mode from thing side to the order as side is:

This first eyeglass has the positive refractive power meniscus shaped lens and towards being concave surface as side; It has at least one side to be aspheric surface again;

This light hurdle;

This second eyeglass has the negative refractive power meniscus shaped lens and towards being concave surface as side; It has at least one side to be aspheric surface again;

This prismatic glasses has the positive refractive power meniscus shaped lens and towards being convex surface as side; It has at least one side to be aspheric surface again;

The 4th eyeglass, having towards the thing side is concave surface; It has at least one side to be aspheric surface again.

2. imaging lens set according to claim 1 is characterized in that, meets the following conditions:

0.3＜|f1|/|f2|＜0.8，

Wherein f1 is the focal length value of first eyeglass, and f2 is the focal length value of second eyeglass.

3. imaging lens set according to claim 1 is characterized in that, meets the following conditions:

0.8＜|f3|/|f4|＜1.3，

Wherein f3 is the focal length value of prismatic glasses, and f4 is the focal length of the 4th eyeglass.

4. imaging lens set according to claim 1 is characterized in that, meets the following conditions:

|f234|/|f|＜2，

Wherein f234 is the synthetic focal length value of second eyeglass, prismatic glasses and the 4th eyeglass, | f| is the focal length value of whole lens set.

5. imaging lens set according to claim 1 is characterized in that, meets the following conditions:

N2＞1.57，

V2＜40，

Wherein N2 is the refractive index of second eyeglass, and V2 is the Abbe coefficient of second eyeglass.

6. imaging lens set according to claim 1 is characterized in that, said aspheric type satisfies formula:

$z=\frac{{\mathrm{ch}}^2}{1+{[1-(k+1)c^2{h}^2]}^{0.5}}+{\mathrm{Ah}}^4+{\mathrm{Bh}}^6+{\mathrm{Ch}}^8+{\mathrm{Dh}}^{10}+{\mathrm{Eh}}^{12}+{\mathrm{Gh}}^{14}+..........$

Wherein z be along optical axis direction highly for the position of h with surface vertices positional value for referencial use; K is awl normal manner amount; C is the inverse of radius-of-curvature; A, B, C, D, E, G ... Be the high-order asphericity coefficient.

Images