CN2833634Y - Zoom lens assembly - Google Patents

Abstract

The utility model discloses a zoom lens assembly with simple structure and short total length. From an object side, the zoom lens assembly orderly comprises a first lens group with negative refractive power, a second lens group with positive refractive power, a third lens group with the negative refractive power, and a fourth lens group with the positive refractive power, wherein the first lens group, the third lens group and the fourth lens group are all composed of single lens bodies. In the zooming process, the first lens group and the fourth lens group are fixed and immovable; the second lens group and the third lens group move from front to rear, and separately zoom and focus for the zoom lens assembly; furthermore, the second lens group is only in one of a wide-angle position and a far shooting position.

Description

The zoom lens combination

Technical field

The utility model relates to the combination of a kind of zoom lens, relates in particular to a kind of zoom lens combination that is applied on the portable type electronic product such as mobile phone.

Background technology

In recent years, have take pictures or the application of the simple and easy digital still camera of recording function, mobile phone, personal digital assistant portable electron devices such as (Personal Digital Assistant are called for short PDA) more and more widely.But the electronic installation that has imaging modules in these requires the total length of its entrained combination of lenses short as far as possible because of the restriction of self thickness usually, and structure is also simple as much as possible.

April 8 2003 Christian era, the United States Patent (USP) of bulletin disclosed the negative combination of lenses of just arranging of a kind of three groups of formulas for the 6th, 545, No. 824.Three groups of lens groups of this combination of lenses are formed by some lens, its complex structure, cause the total length of combination of lenses bigger, thereby be not suitable for being applied on the portable type electronic product, and second lens group moves forward and backward to realize focus function can not realize zoom function, carries out elasticity and finds a view thereby this combination of lenses can not change visible sensation distance when taking pictures.

Again, the United States Patent (USP) of announcing May 10 2005 Christian era has disclosed the positive and negative combination of lenses of just arranging of a kind of four group formula for the 6th, 891, No. 680.This combination of lenses is realized zoom function by moving second group and the 3rd group continuously, and the lens that move between two lens in these front and back continuously by fixing two lens in front and back of first group are reached focusing function.This type of continuous vari-focus mode designs needs complicated control structure, therefore causes the volume of the camera lens with this combination of lenses big, complex structure, so this combination of lenses also is unsuitable for being applied on the portable type electronic product.

Therefore, how to provide a kind of zoom lens that overcomes the problems referred to above to become the problem that needs to be resolved hurrily.

Summary of the invention

The purpose of this utility model provides a kind of zoom lens combination, has characteristics simple in structure, that total length is short.

For achieving the above object, zoom lens provided by the utility model combination is from the thing side direction, comprises first lens group, second lens group with positive refractive power with negative refractive power successively, has the 3rd lens group of negative refractive power and has the 4th lens group of positive refractive power.Wherein, first lens group, the 3rd lens group and the 4th lens group are single mirror body composition.In the zoom process, first lens group and the 4th lens group maintain static; Second lens group and the 3rd lens group move forward and backward, and respectively to this zoom lens combination carrying out zoom and focusing, wherein second lens group only is in wide-angle position and takes the photograph one of distant positions.

As mentioned above, because being single mirror body, first lens group, the 3rd lens group and the 4th lens group of the combination of the utility model zoom lens form, when zoom, first lens group and the 4th lens group of this zoom lens combination maintain static, the total length of zoom lens combination is fixed, and second lens group only is in wide-angle position or takes the photograph distant positions, thereby the zoom lens combination is simple in structure, total length is shorter.

Description of drawings

Below in conjunction with drawings and Examples the utility model is described in further detail.

Fig. 1 is in the sectional view of wide-angle position for first embodiment of the utility model zoom lens combination.

Fig. 2 is in the sectional view of taking the photograph distant positions for first embodiment of the utility model zoom lens combination.

Fig. 3 A is in the spherical aberration diagram of wide-angle position for first embodiment of the utility model zoom lens combination.

Fig. 3 B is in the astigmatism figure of wide-angle position for first embodiment of the utility model zoom lens combination.

Fig. 3 C is in the distortion figure of wide-angle position for first embodiment of the utility model zoom lens combination.

Fig. 4 A is in the spherical aberration diagram of taking the photograph distant positions for first embodiment of the utility model zoom lens combination.

Fig. 4 B is in the astigmatism figure that takes the photograph distant positions for first embodiment of the utility model zoom lens combination.

Fig. 4 C is in the distortion figure that takes the photograph distant positions for first embodiment of the utility model zoom lens combination.

Fig. 5 is in the sectional view of wide-angle position for second embodiment of the utility model zoom lens combination.

Fig. 6 is in the sectional view of taking the photograph distant positions for second embodiment of the utility model zoom lens combination.

Fig. 7 A is in the spherical aberration diagram of wide-angle position for second embodiment of the utility model zoom lens combination.

Fig. 7 B is in the astigmatism figure of wide-angle position for second embodiment of the utility model zoom lens combination.

Fig. 7 C is in the distortion figure of wide-angle position for second embodiment of the utility model zoom lens combination.

Fig. 8 A is in the spherical aberration diagram of taking the photograph distant positions for second embodiment of the utility model zoom lens combination.

Fig. 8 B is in the astigmatism figure that takes the photograph distant positions for second embodiment of the utility model zoom lens combination.

Fig. 8 C is in the distortion figure that takes the photograph distant positions for second embodiment of the utility model zoom lens combination.

Embodiment

For describing technology contents of the present utility model, the purpose of being reached and effect in detail, below now for embodiment and cooperate the graphic detailed explanation of giving.

See also Fig. 1 and Fig. 2, it discloses first embodiment of zoom lens combination 100 of the present utility model.In the present embodiment, from the thing side, zoom lens combination 100 comprises first lens group 110, second lens group 120 with positive refractive power with negative refractive power successively, have the 3rd lens group 130 of negative refractive power and have the 4th lens group 140 of positive refractive power.

First lens group 110 is made up of a single mirror body (balsaming lens, compound lens or single eyeglass), and in the present embodiment, it is made up of a slice double-concave negative lens 111.For reducing the aberration of combination of lenses 100, the Abbe number of double-concave negative lens 111 is more preferably greater than 50.For reducing the aberration of combination of lenses 100, the plane of refraction towards the thing side of this double-concave negative lens 111 is a sphere, is aspheric surface towards the plane of refraction as side in addition, and this aspheric surface can be represented with following formula (1):

$X=\frac{{\mathrm{<figure-callout\; id="2"\; label="cS"\; filenames="Y20052010408200201.png"\; state="\{\{state\}\}">cS</figure-callout>}}^2}{1+\sqrt{1-(K+1)c^2{\mathrm{<figure-callout\; id="2"\; label="S"\; filenames="Y20052010408200201.png"\; state="\{\{state\}\}">S</figure-callout>}}^2}}+A_4{S}^4+A_6{S}^6+A_8{S}^8+A_{10}{S}^{10}+A_{12}{S}^{12}---\left(1\right)$

Wherein, c represents the curvature at place, aspheric surface refracting surface summit, S represents the distance from the aspheric surface refracting surface coordinate points to optical axis, K represents the circular cone coefficient, A4, A6, A8 and A10 represent asphericity coefficient, X represent from and optical axis distance be that the aspheric surface refracting surface coordinate points of S is to the distance the section on aspheric surface refracting surface summit.

Second lens group 120 comprises three lens, and it is followed successively by biconvex positive lens 121, concavo-convex negative lens 122 and convex-concave negative lens 123.Tear the face of penetrating open for two of convex-concave negative lens 123 and be all aspheric surface, these aspheric surfaces can be used formula (1) expression.The material of biconvex positive lens 121 and concavo-convex negative lens 122 is a flint glass.In addition, second lens group 120 also comprises an aperture diaphragm (not marking among the figure), and this aperture diaphragm is fixed as one on the plane of refraction of thing side and with second lens group 120 attached to biconvex positive lens 121, together to move with second lens group 120.

The 3rd lens group 130 is made up of the concavo-convex negative lens 131 of a slice, and two planes of refraction of this concavo-convex negative lens 131 are all aspheric surface, and these aspheric surfaces are also used formula (1) expression.

The 4th lens group 140 is made up of a slice biconvex positive lens 141, is used to improve the focusing heart far away (Telecentricity) of combination of lenses 100, and biconvex positive lens 141 maintains static, in order to the protection image sensor.

Illustrate that below in conjunction with Fig. 1 and Fig. 2 zoom lens of the present utility model make up 100 zoom process.

First lens group 110 and the 4th lens group 140 maintain static, and move second lens group 120 and the 3rd lens group 130 respectively zoom and focusing are carried out in this zoom lens combination 100.In above-mentioned zoom process, by second lens group 120 is moved to the another location to change the focal length of zoom lens combination 100 by a position, thereby reach the zoom function of zoom lens combination 100, by the 3rd lens group 130 being moved to the relevant position zoom lens combination 100 is focused on, thereby reach the focusing function of zoom lens combination 100.Thereby, this kind zoom mode is different from the continuous vari-focus mode, and the selection zoom position that only can disperse and reach the sectional type zoom, thereby can simplify the zoom of this zoom lens combination 100 and focusing control structure, reduce the volume of this zoom lens combination 100, thereby these zoom lens make up 100 and are suitable for being applied on the portable electron device.In the present embodiment, primary importance is a wide-angle side, and the second place is for taking the photograph far-end.When second lens group 120 was in wide-angle position, as shown in Figure 1, second lens group 120 and the 3rd lens group 130 were near the 4th lens group 140; When second lens group 120 is in when taking the photograph distant positions, as shown in Figure 2, second lens group 120 and the 3rd lens group 130 are near first lens groups 110, and with respect to primary importance, the distance between second lens 120 and the 3rd lens 130 becomes greatly.

The particular data relevant with first embodiment is listed in the table one, two, wherein, R represents radius-of-curvature, d1, d2 represent the distance between the lens plane of refraction summit of first and second position respectively, v represents the Abbe number of lens, the pupil radius of PR (Pupil Radius) expression sectional type zoom lens 100, the maximum image field of MF (Maximum Field) expression sectional type zoom lens 100, nd represents that (refractive index of λ=587.6nm), the unit of d1, d2 and R is " mm " to the d line in addition.

Table one

Plane of refraction	R	d 1	d 2	n d	v
							1 2 3 4 5 6 7 8 9 10 11 12	-4.4515 11.0505 2.0000 -5.2023 -3.2432 -17.5112 2.9675 1.5177 -9.0822 -50.9269 26.5590 -8.2526	0.6000 1.5748 1.1118 0.1000 0.7420 0.3391 0.6072 0.6651 0.8000 0.8051 1.3548 0.3000	0.6000 0.1000 1.1118 0.1000 0.7420 0.3391 0.6072 1.6060 0.8000 1.3391 1.3548 0.3000	1.525 1.804 1.806 1.805 1.607 1.525 1.805	56.3 46.5 25.5 25.5 27.6 56.3 25.5	Aspheric surface aperture diaphragm aspheric surface aspheric surface aspheric surface aspheric surface

Table two

Plane of refraction	K	A 4	A 6	A 8	A 10
						2 7 8 9 10	39.0062 -17.1964 -0.1246 -10 -10	-4.05740E-03 -1.97602E-02 -6.69706E-02 3.67969E-03 -6.79528E-03	-1.50710E-03 -1.22007E-01 -6.12734E-02 9.51233E-03 4.30880E-03	-1.14035E-04 6.30003E-02 3.53452E-02 -1.95842E-03 -7.83427E-04	9.22284E-06 -4.58731E-02 -9.16573E-03 1.69337E-04 1.17297E-04

In the present embodiment, the focal length of each lens group is as follows:

f1＝-5.9428

f2＝2.8059

f3＝-21.1167

f4＝7.8855

Wherein, f1 represents the focal length of first lens group 110, and f2 represents the focal length of second lens group 120, and f3 represents the focal length of the 3rd lens group 130, and f4 represents the focal length of the 4th lens group 140.

Spherical aberration diagram, astigmatism figure, distortion figure when the zoom lens combination 100 that Fig. 3 A-3C is respectively present embodiment is in wide-angle position, Fig. 4 A-4C is respectively zoom lens combination 100 spherical aberration diagram, astigmatism figure, the distortion figure that are in when taking the photograph distant positions of present embodiment, wherein, by D line (λ=546.0740nm), F line (λ=486.1327nm) and the C line (optical characteristics of the various aberrations explanation zoom lens combination 100 of λ=632.8000nm), in astigmatism figure, the S line is the radial astigmatism curve, and the T line is tangential astigmatism curve.

Fig. 5 and Fig. 6 disclose second embodiment of zoom lens of the present utility model combination 100, and present embodiment is similar to Fig. 1, embodiment shown in Figure 2, and its difference mainly is: present embodiment the 3rd lens group 130 ' is made up of a concave-concave negative lens 131 '.

The particular data relevant with second embodiment is listed in the table three, four, and its special parameter meaning is described in first embodiment.

Table three

Plane of refraction	R	d 1	d 2	n d	v
							1 2 3 4 5 6 7 8 9 10 11 12	-4.1496 12.0411 2.0000 -4.5897 -2.9064 -11.7521 2.8700 1.4902 -7.3170 83.5899 58.3954 -5.8623	0.6000 1.5137 1.0825 0.1000 0.7500 0.3991 0.6000 0.5859 0.8000 0.7094 1.4593 0.3000	0.6000 0.1000 1.0825 0.1000 0.7500 0.3991 0.6000 1.3036 0.8000 1.4054 1.4593 0.3000	1.525 1.804 1.806 1.805 1.607 1.525 1.805	56.3 46.5 25.5 25.5 27.6 56.3 25.5	Aspheric surface aperture diaphragm aspheric surface aspheric surface aspheric surface aspheric surface

Table four

Plane of refraction	K	A 4	A 6	A 8	A 10
						2 7 8 9 10	18.5534 -13.3166 0.047888 -10 -10	-1.69078E-03 -2.39933E-02 -5.95527E-02 1.59720E-02 6.63994E-04	-1.18934E-03 -1.19464E-01 -8.94148E-02 4.12035E-03 1.74196E-03	-1.35367E-04 5.96592E-02 5.08341E-02 -5.30247E-04 -5.73486E-04	1.72931E-04 -4.63294E-02 -1.54165E-02 3.38511E-05 1.38850E-04

In the present embodiment, the focal length of each lens group is as follows:

f1＝-5.78

f2＝2.70

f3＝-12.73

f4＝6.62

Wherein, f1 represents the focal length of first lens group 110, and f2 represents the focal length of second lens group 120, and f3 represents the focal length of the 3rd lens group 130 ', and f4 represents the focal length of the 4th lens group 140.

Fig. 7 A-7C and Fig. 8 A-8C are the various aberration diagrams of the zoom lens combination 100 of present embodiment when being in wide-angle position respectively and taking the photograph distant positions, and its each symbolic significance is described in first embodiment.

Claims (6)

1, a kind of zoom lens combination, from the thing side direction, comprise successively: first lens group, second lens group, the 3rd lens group, the 4th lens group is characterized in that:

First lens group has negative refractive power;

Second lens group has positive refractive power;

The 3rd lens group has negative refractive power;

The 4th lens group has positive refractive power;

Wherein, first lens group, the 3rd lens group and the 4th lens group are formed by single mirror body; First lens group and the 4th lens group maintain static; Second lens group and the 3rd lens group move forward and backward, and respectively to this zoom lens combination carrying out zoom and focusing, wherein second lens group only is in wide-angle position and takes the photograph one of distant positions.

2, zoom lens combination as claimed in claim 1, it is characterized in that: first lens group is made up of a slice double-concave negative lens, and this double-concave negative lens is a sphere towards the plane of refraction of thing side, and described plane of refraction away from the thing side is an aspheric surface.

3, zoom lens combination as claimed in claim 1, it is characterized in that: described second lens group is made up of biconvex positive lens, concavo-convex negative lens and convex-concave negative lens, and two planes of refraction of convex-concave negative lens are aspheric surface.

4, zoom lens combination as claimed in claim 1, it is characterized in that: described the 3rd lens group is made up of a slice double-concave negative lens, and two planes of refraction of this double-concave negative lens are aspheric surface.

5, zoom lens combination as claimed in claim 1, it is characterized in that: described the 3rd lens group is made up of the concavo-convex negative lens of a slice, and two planes of refraction of this concavo-convex negative lens are aspheric surface.

6, zoom lens combination as claimed in claim 1, it is characterized in that: described the 4th lens group is made up of a slice biconvex positive lens.

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