CN203941335U - The little distortion reversing of a kind of high definition wide-angle camera lens - Google Patents

The little distortion reversing of a kind of high definition wide-angle camera lens Download PDF

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Publication number
CN203941335U
CN203941335U CN201420221520.0U CN201420221520U CN203941335U CN 203941335 U CN203941335 U CN 203941335U CN 201420221520 U CN201420221520 U CN 201420221520U CN 203941335 U CN203941335 U CN 203941335U
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China
Prior art keywords
lens
reversing
high definition
camera lens
little distortion
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Expired - Lifetime
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CN201420221520.0U
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Chinese (zh)
Inventor
黄福建
宋勇
范家忠
陈婷
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XINHUA PRECISION MACHINERY CO Ltd
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XINHUA PRECISION MACHINERY CO Ltd
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Abstract

The utility model discloses the little distortion reversing of a kind of high definition wide-angle camera lens, it is characterized in that, comprise the first lens with negative power being coaxially arranged in order to imaging surface from thing end, second lens with negative power, the 3rd lens and the 4th lens, described the 3rd lens are biconvex spherical glass lens, the 4th lens are plastic cement aspheric surface biconvex lens, aperture member is located between the 3rd and the 4th lens element, the little distortion reversing of described high definition wide-angle camera lens meets the following conditions: TTL<20mm, wherein, TTL is the length of whole reversing camera lens.The reversing camera lens that meets above-mentioned condition of the present utility model, field angle is large, and focal length is little, ensures that reversing process sees larger scope, have higher resolving power and less distortion, and image is limpid in sight.

Description

The little distortion reversing of a kind of high definition wide-angle camera lens
Technical field
The utility model relates to a kind of optical instrument, belongs to field of video monitoring, specifically refers to the little distortion reversing of a kind of high definition wide-angle camera lens.
Background technology
Visual information is people by one of main source of objective world acquired information, accounts for people and relies on 70% of face acquired information, and the ocular effect therefore being provided by image is not that language and text description can reach.Video image is actually continuous still image sequence, is to objective things image, lively description, is a kind of expression way more directly perceived and concrete.Along with the fast development of network, communication and microelectric technique, the feature such as video monitoring system is directly perceived with it, convenient and abundant in content, is subject to people's attention day by day.
The today day by day coming into one's own at automotive safety, increasing car owner can be for the love car of oneself is equipped with a series of auto-safety mechanism, and video vehicle back radar system is also more and more subject to liking of numerous Ai Che gangs.Video vehicle back radar is in the time hanging reverse gear shift, this system can be connected the high-definition camera that is positioned at the tailstock automatically, situation after car is shown in LCDs clearly, and the radar that video vehicle back radar is compared Echo Sounding distance in the time of reversing automobile shows more intuitively, also safer.In the market the visual angle of the wide-angle lens in vehicle-mounted camera being required generally more than 160 °, but formed by six spherical glass eyeglasses by prior art design wide-angle lens, after visual angle is greater than 120 °, amount of distortion can present growth fast, makes imaging image gross distortion out.Traditional bugeye lens great majority exist distortion excessive, make imaging image gross distortion out, affect the judgement that driver adjusts the distance.
In order to solve the excessive problem of distortion, publication number is that the Chinese utility model patent of CN101561550B has disclosed a kind of wide-angle and low-distortion on-vehicle lens, it comprises from object space and starts to be provided with successively first lens element, the second lens element, the 3rd lens element and the 4th lens element, aperture member is located between the 3rd and the 4th lens element, and described first lens element has negative focal power the protruding curved month type eyeglass to object space; The second described lens element has negative focal power the protruding curved month type eyeglass to object space; The 3rd described lens element has the biconvex eyeglass of positive focal power; The 4th described lens element has the biconvex eyeglass of positive focal power; First lens object space side outermost point to the distance of imaging surface of described on-vehicle lens will meet following formula: TTL >=20mm.It adopts 4 eyeglasses, although reached good optical characteristics and wider total field angle, it has longer camera lens overall length is that TTL approaches 25mm, cause the volume of camera lens larger, and its distortion still has 50% left and right.On the other hand, all also there is the not good problem of imaging in existing reversing camera lens, and curvature of the image is unintelligible.
Utility model content
The purpose of this utility model is to overcome above-mentioned deficiency of the prior art, provides one to improve resolving power, has reduced distortion, has dwindled Lens, has improved the combination property of camera lens and has saved the little distortion reversing of the high definition wide-angle of cost camera lens.
The purpose of this utility model is achieved through the following technical solutions:
The little distortion reversing of a kind of high definition wide-angle camera lens, comprise the first lens with negative power being coaxially arranged in order to imaging surface from thing end, second lens with negative power, the 3rd lens and the 4th lens, described the 3rd lens are biconvex spherical glass lens, the 4th lens are plastic cement aspheric surface biconvex lens, aperture member is located between the 3rd and the 4th lens element, the little distortion reversing of described high definition wide-angle camera lens meets the following conditions: TTL<20mm, wherein, TTL is the length of whole reversing camera lens.Meet the reversing camera lens of above-mentioned condition, ensureing that on the basis of outstanding optical property, diaphragm is placed on the centre of two biconvex lens, be conducive to the optimization of distortion; Adopt less TTL, dwindled the volume of camera lens, there is the image quality of the little high resolving power of length, low aberration.
Concrete, the little distortion reversing of described high definition wide-angle camera lens also comprises an optical filter, described optical filter is between described the 4th lens and imaging surface.
Concrete, described first lens is curved month type glass spherical lens, concave surface is towards optical filter, and the model of its material is H-LAF50A; The second lens are curved month type plastic aspheric lenes, and concave surface is towards optical filter, and the model of its material is E48R; The model of the material of described the 3rd lens is H-ZF62; The model of the material of described the 4th lens is E48R.Adopt said structure and different optimization of material reversing camera lenses, the camera lens that makes to move backward has less distortion.
Concrete, this first lens is from thing side to comprising successively a first surface and second surface as side, described the second lens are from thing side to comprise successively one the 3rd surface and one the 4th surface as side, described the 3rd lens are from thing side to comprise successively one the 5th surface and one the 6th surface as side, described the 4th lens are from thing side to comprise successively one the 7th surface and one the 8th surface as side, the little distortion reversing of described high definition wide-angle camera lens also meets the following conditions: D/L>0.6, wherein, D is maximum imaging circular diameter on imaging surface, L is the effective diameter of the exiting surface on the 8th surface.
Concrete, described first lens and the 3rd lens formula that meets the following conditions:
8 < R1/d12 < 11, and 2.5 < R2/d12 < 5.5, and 2.1 < R1/R2 < 2.5,
Wherein, the radius-of-curvature that R1 is first surface, the radius-of-curvature that R2 is second surface, d12 is the thickness between first surface and second surface;
1.5 < R5/d56 < 1.9, and-11 < R6/d56 <-8, and-0.19 < R5/R6 <-0.15,
Wherein R5 is the radius-of-curvature on the 5th surface, and R6 is the radius-of-curvature on the 6th surface, and d56 is the thickness between the 5th surface and the 6th surface.
Preferably, described first lens and the 3rd lens formula that meets the following conditions:
1.7 < Nd12 < 1.8, and 48 < Vd12 < 52, wherein, Nd12 is the refractive index of material between first surface and second surface, and Vd12 is the abbe number of material between first surface and second surface;
1.90 < Nd56 < 1.94, and 19 < Vd56 < 23, wherein, Nd56 is the refractive index of the material between the 5th surface and the 6th surface, and Vd56 is the abbe number of material between the 5th surface and the 6th surface.
Concrete, described first lens and the 3rd lens formula that also meets the following conditions:
-11 < F1 <-9, and 3.5 < F3 < 5.5, wherein, the focal length value that F1 is first lens, F3 is the focal length value of the 3rd lens.
Concrete, described the second lens and the 4th lens formula that meets the following conditions:
1.50 < Nd34 < 1.55, and 54 < Vd34 < 58, and 1.50 < Nd78 < 1.55, and 54 < Vd78 < 58
Wherein, Nd34 is the refractive index of material between the 3rd surface and the 4th surface, Vd34 is the abbe number of material between the 3rd surface and the 4th surface, and Nd78 is the refractive index of material between the 7th surface and the 8th surface, and Vd78 is the abbe number of material between the 7th surface and the 8th surface.
Concrete, described the 3rd surface, the 4th surface, the 7th surface, the 8th surface are aspheric surface, and should
Concrete, the little distortion reversing of described high definition wide-angle camera lens overall length meets the following conditions:
TTL>10mm。
The utility model has the following advantages and beneficial effect compared to existing technology:
1, the reversing camera lens that meets above-mentioned condition of the present utility model, field angle is large, and focal length is little, ensures that reversing process sees larger scope, have higher resolving power and less distortion, and image is limpid in sight.
2, reversing camera lens of the present utility model is on the basis of large visual field (horizontal field of view angle 120 is spent) and little F value (2.4), adopt different materials and different eyeglass curvature, obtain less distortion, distortion is about 10%, distortion reduces greatly, has improved the combination property of camera lens and has saved cost.
Brief description of the drawings
The structural representation of the imaging lens that Fig. 1 provides for the utility model.
The MTF curve of the imaging lens that Fig. 2 provides for the utility model.
The distortion curve figure of the imaging lens that Fig. 3 provides for the utility model.
Embodiment
Below in conjunction with embodiment and accompanying drawing, the utility model is described in further detail, but embodiment of the present utility model is not limited to this.
Embodiment
As shown in Figure 1, the present embodiment provides the little distortion reversing of a kind of high definition wide-angle camera lens, comprise the first lens with negative power 1 being coaxially arranged in order to imaging surface from thing end, second lens 2 with negative power, the 3rd lens 3 and the 4th lens 4, an aperture member 5 and an optical filter 6, wherein, first lens 1 is curved month type glass spherical lens, and concave surface is towards optical filter 6; The second lens 2 are curved month type plastic aspheric lenes, and concave surface is towards optical filter 6; The 3rd lens 3 are glass biconvex spherical lens, the 4th lens 4 are plastic cement aspheric surface biconvex lens, aperture member 5 is located between the 3rd and the 4th lens element, described optical filter is between described the 4th lens and imaging surface, the little distortion reversing of described high definition wide-angle camera lens meets the following conditions: TTL<20mm, wherein, TTL is the length of whole reversing camera lens.
Concrete, described first lens is curved month type glass spherical lens, concave surface is towards optical filter, and the model of its material is H-LAF50A; The second lens are curved month type plastic aspheric lenes, and concave surface is towards optical filter, and the model of its material is E48R; The model of the material of described the 3rd lens is H-ZF62; The model of the material of described the 4th lens is E48R.The combination of first lens to the four lens has and reduces the ability that distorts, therefore its position and material behavior own in optical system, thereby make the external diameter of this optical lens may diminish to 13.87mm, provable reversing camera lens of the present utility model like this can effectively be revised aberration and can effectively dwindle again image-forming range; While simultaneously arriving 120 ° than existing camera lens, the chances are 70% in distortion, and the design's camera lens while arriving 120 ° distortion can reduce to 10%.
This first lens is from thing side to comprising a first surface and second surface as side successively, described the second lens are from thing side to comprise successively one the 3rd surface and one the 4th surface as side, described the 3rd lens are from thing side to comprise successively one the 5th surface and one the 6th surface as side, described the 4th lens are from thing side to comprise successively one the 7th surface and one the 8th surface as side, the little distortion reversing of described high definition wide-angle camera lens also meets the following conditions: D/L>0.6, wherein, D is maximum imaging circular diameter on imaging surface, and L is the effective diameter of the exiting surface on the 8th surface.The design of employing said structure, makes sampling image lens can have short back focal length, can effectively shorten the distance of camera lens from object to imaging surface, to reduce the volume of camera lens, and promotes the application of sampling image lens.
Described first lens and the 3rd lens formula that meets the following conditions:
8 < R1/d12 < 11, and 2.5 < R2/d12 < 5.5, and 2.1 < R1/R2 < 2.5,
Wherein, the radius-of-curvature that R1 is first surface, the radius-of-curvature that R2 is second surface, d12 is the thickness between first surface and second surface; 1.5 < R5/d56 < 1.9, and-11 < R6/d56 <-8, and-0.19 < R5/R6 <-0.15, wherein R5 is the radius-of-curvature on the 5th surface, R6 is the radius-of-curvature on the 6th surface, and d56 is the thickness between the 5th surface and the 6th surface.If R/d is too small, R value is too small, is unfavorable for the optimization of spherical aberration, also causes processing difficulties, or eyeglass is too thick, is unfavorable for reducing TTL; If R1/d12 is excessive, eyeglass is too thin is unfavorable for processing, or R is excessive, may cause whole optical system volume bigger than normal, therefore, meets the eyeglass of this above-mentioned feature, is conducive to the optimization of camera lens.
Described first lens and the 3rd lens formula that meets the following conditions:
1.7 < Nd12 < 1.8, and 48 < Vd12 < 52, wherein, Nd12 is the refractive index of material between first surface and second surface, and Vd12 is the abbe number of material between first surface and second surface; 1.90 < Nd56 < 1.94, and 19 < Vd56 < 23, wherein, Nd56 is the refractive index of the material between the 5th surface and the 6th surface, and Vd56 is the abbe number of material between the 5th surface and the 6th surface.Said structure adopts the glass of large refractive index to be conducive to camera lens to accommodate the light of larger field angle, and refractive index need not be excessive, because excessive refractive index can cause the increase of glass cost, therefore, first lens adopts the material of high abbe number, be conducive to camera lens and accommodate the light of larger field angle, and the 3rd lens adopt the material of low abbe number, are the optimization that is conducive to aberration.
Described first lens and the 3rd lens formula that also meets the following conditions:
-11 < F1 <-9, and 3.5 < F3 < 5.5, wherein, the focal length value that F1 is first lens, F3 is the focal length value of the 3rd lens.First lens and the 3rd lens meet this focal length relation, and the size of being convenient to control TTL is between 10~20mm.
Described the second lens and the 4th lens formula that meets the following conditions:
1.50 < Nd34 < 1.55, and 54 < Vd34 < 58, and 1.50 < Nd78 < 1.55, and 54 < Vd78 < 58, wherein, Nd34 is the refractive index of material between the 3rd surface and the 4th surface, Vd34 is the abbe number of material between the 3rd surface and the 4th surface, Nd78 is the refractive index of material between the 7th surface and the 8th surface, Vd78 is the abbe number of material between the 7th surface and the 8th surface.Take to meet the plastic material of this relation, realize and coordinating better with glass mirror, and color difference eliminating better.
Concrete, described the 3rd surface, the 4th surface, the 7th surface, the 8th surface are aspheric surface, and
Wherein, in formula, n is even number, and y represents the y coordinate figure of lens surface each point, and R is paraxial radius of circle, and K is asphericity coefficient, and x represents the x coordinate figure of lens surface each point, A 2, A 4, A 6a nrepresent A 2to A nrepresent respectively the corresponding coefficient of each radial coordinate, can accurately set the geomery of lens front and back both-sided aspherical by above parameter.
Concrete, the little distortion reversing of described high definition wide-angle camera lens overall length meets the following conditions:
TTL>10mm。
Concrete lens parameters of the present utility model is in table 1:
Table 1
Table 2 is second lens of the present embodiment and aspheric surface high-order term COEFFICIENT K, A4, A6, A8, A10, the A12 of the 4th lens aspherical lens.
Table 2
Face sequence number K A4 A6 A8 A10 A12
The 3rd surface -1.027617 -0.036059 -0.001250 0.000739 -0.000065 0.000002
The 4th surface -0.925871 -0.126060 0.015961 -0.012837 0.004100 -0.000472
The 7th surface -44.253870 0.023786 0.023632 -0.035349 -0.045561 0.048843
The 8th surface -10.727238 -0.103507 0.035081 0.009980 -0.007780 0.001290
Fig. 2 to Fig. 3 is the optical performance curve figure corresponding to the present embodiment, and wherein Fig. 2 is MTF curve map, has represented that the comprehensive solution of an optical system is as level.Fig. 3 is distortion curve figure, represents the distortion sizes values in different field angle situations, and unit is %, and as shown in Figure 3, the distortion of camera lens of the present utility model is about 10%, and distortion reduces greatly.
Above-described embodiment is preferably embodiment of the utility model; but embodiment of the present utility model is not restricted to the described embodiments; other any do not deviate from change, the modification done under Spirit Essence of the present utility model and principle, substitutes, combination, simplify; all should be equivalent substitute mode, within being included in protection domain of the present utility model.

Claims (10)

1. the little distortion reversing of a high definition wide-angle camera lens, it is characterized in that, comprise the first lens with negative power being coaxially arranged in order to imaging surface from thing end, second lens with negative power, the 3rd lens and the 4th lens, described the 3rd lens are biconvex spherical glass lens, the 4th lens are plastic cement aspheric surface biconvex lens, aperture member is located between the 3rd and the 4th lens element, the little distortion reversing of described high definition wide-angle camera lens meets the following conditions: TTL<20mm, wherein, TTL is the length of whole reversing camera lens.
2. the little distortion reversing of high definition wide-angle according to claim 1 camera lens, is characterized in that, the little distortion reversing of described high definition wide-angle camera lens also comprises an optical filter, and described optical filter is between described the 4th lens and imaging surface.
3. the little distortion reversing of high definition wide-angle according to claim 2 camera lens, is characterized in that, described first lens is curved month type glass spherical lens, and concave surface is towards optical filter, and the model of its material is H-LAF50A; The second lens are curved month type plastic aspheric lenes, and concave surface is towards optical filter, and the model of its material is E48R; The model of the material of described the 3rd lens is H-ZF62; The model of the material of described the 4th lens is E48R.
4. the little distortion reversing of high definition wide-angle according to claim 1 camera lens, it is characterized in that, this first lens is from thing side to comprising successively a first surface and second surface as side, described the second lens are from thing side to comprise successively one the 3rd surface and one the 4th surface as side, described the 3rd lens are from thing side to comprise successively one the 5th surface and one the 6th surface as side, described the 4th lens are from thing side to comprise successively one the 7th surface and one the 8th surface as side, and the little distortion reversing of described high definition wide-angle camera lens also meets the following conditions: D/L>0.6; Wherein, D is maximum imaging circular diameter on imaging surface, and L is the effective diameter of the exiting surface on the 8th surface.
5. the little distortion of high definition wide-angle according to claim 4 reversing camera lens, is characterized in that, described first lens and the 3rd lens formula that meets the following conditions:
8 < R1/d12 < 11, and 2.5 < R2/d12 < 5.5, and 2.1 < R1/R2 < 2.5,
Wherein, the radius-of-curvature that R1 is first surface, the radius-of-curvature that R2 is second surface, d12 is the thickness between first surface and second surface;
1.5 < R5/d56 < 1.9, and-11 < R6/d56 <-8, and-0.19 < R5/R6 <-0.15,
Wherein, R5 is the radius-of-curvature on the 5th surface, and R6 is the radius-of-curvature on the 6th surface, and d56 is the thickness between the 5th surface and the 6th surface.
6. the little distortion of high definition wide-angle according to claim 4 reversing camera lens, is characterized in that, described first lens and the 3rd lens formula that meets the following conditions:
1.7 < Nd12 < 1.8, and 48 < Vd12 < 52,
Wherein, Nd12 is the refractive index of material between first surface and second surface, and Vd12 is the abbe number of material between first surface and second surface;
1.90 < Nd56 < 1.94, and 19 < Vd56 < 23,
Wherein, Nd56 is the refractive index of the material between the 5th surface and the 6th surface, and Vd56 is the abbe number of material between the 5th surface and the 6th surface.
7. the little distortion of high definition wide-angle according to claim 1 reversing camera lens, is characterized in that, described first lens and the 3rd lens formula that also meets the following conditions:
-11 < F1 <-9, and 3.5 < F3 < 5.5, the focal length value that wherein F1 is first lens, F3 is the focal length value of the 3rd lens.
8. the little distortion of high definition wide-angle according to claim 4 reversing camera lens, is characterized in that, described the second lens and the 4th lens formula that meets the following conditions:
1.50 < Nd34 < 1.55, and 54 < Vd34 < 58, and 1.50 < Nd78 < 1.55, and 54 < Vd78 < 58
Wherein, Nd34 is the refractive index of material between the 3rd surface and the 4th surface, Vd34 is the abbe number of material between the 3rd surface and the 4th surface, and Nd78 is the refractive index of material between the 7th surface and the 8th surface, and Vd78 is the abbe number of material between the 7th surface and the 8th surface.
9. according to the little distortion reversing of the high definition wide-angle described in claim 4,5,6 or 8 camera lens, it is characterized in that, described the 3rd surface, the 4th surface, the 7th surface, the 8th surface are aspheric surface, and this aspheric surface
10. according to the little distortion reversing of the high definition wide-angle described in claim 1-8 any one camera lens, it is characterized in that, the little distortion reversing of described high definition wide-angle camera lens overall length meets the following conditions: TTL>10mm.
CN201420221520.0U 2014-04-30 2014-04-30 The little distortion reversing of a kind of high definition wide-angle camera lens Expired - Lifetime CN203941335U (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104035185B (en) * 2014-04-30 2017-01-25 信华精机有限公司 High-definition wide-angle small-distortion reversing lens

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104035185B (en) * 2014-04-30 2017-01-25 信华精机有限公司 High-definition wide-angle small-distortion reversing lens

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