CN200989959Y

CN200989959Y - Image shooting lens unit

Info

Publication number: CN200989959Y
Application number: CNU2006201565397U
Authority: CN
Inventors: 陈天庆
Original assignee: Genius Electronic Optical Xiamen Co Ltd
Current assignee: Genius Electronic Optical Xiamen Co Ltd
Priority date: 2006-12-19
Filing date: 2006-12-19
Publication date: 2007-12-12
Anticipated expiration: 2016-12-19

Abstract

The utility model relates to an image ingesting lens unit, which comprises an image space as follows, a first lens, a diaphragm, a second lens, a third lens and a fourth lens from an object space to; wherein the diaphragm is arranged between the first lens and the second lens. The first lens of dioptrical function in the positive direction has a convex surface facing the object space and at least an aspherical surface; the second lens of falcate shape and dioptrical function in the negative direction has a concave surface facing the object space and at least an aspherical surface; the third lens of falcate shape and dioptrical function in the positive direction has a convex surface facing the object space, an aspherical lateral surface of the object space and an aspherical lateral surface of the image space. While the classical design is to reduce all aberrations with more structures, the optical system can have better performance in correcting the aberration by applying the aspherical surface only and all aberrations can be reduced with less lens structures, thus simplifying the structure of the system as well as improving the quality.

Description

A kind of image capturing lens unit

Technical field

The utility model relates to a kind of image capturing lens unit, especially refers to a kind of not only adaptive imageing sensor (as CMOS or CCD) but also the image capturing lens unit with photo-quality imaging quality.

Background technology

In recent years, along with digital video market is day by day flourishing, various new technologies, new product continued to bring out.But for example numerous and confused on the market at present mobile phone, the equipment such as PDA, PC that many subsidiary shoot functions occur especially can be taken the focus that portable equipment becomes consumer electronics field rapidly.Simultaneously, along with the lifting of people's living standard and mobile communication service easily, people are to taking the corresponding lifting that requires of portable equipment image quality.But the imageing sensor that portable equipment adopted that possesses shoot function is (as CCD, Charge Coupled Device, charge-coupled image sensor or CMOS, Complementary Metal Oxide Semiconductor, complementary metal oxide semiconductor (CMOS)) to microminaturization and the development of high pixel, reach the pick-up lens that attaches on it for the portable equipment main body, when reducing cost, also be required to reach the performance of microminaturization, high resolving power and high-contrast.

And for imaging system, reach microminaturization, need the eyeglass decreased number to minimum, at present, all be designed to the three-chip type structure substantially, design with reference to U.S.'s publication document US 6961191, though this design adds aperture diaphragm between first lens and second lens, can reduce the dazzle (being Flare) of image, still, on the one hand, only go to consider that from the eyeglass arrangement architecture dazzle of image is not enough, in fact any eyeglass and mechanism assembly all have reflex to light, if do not consider reflection problems in the imaging system design process, then be bound to produce serious image dazzle, can't reach good image quality; On the other hand, the problem that this design is not considered is, but capture apparatus is at CCD or cmos image sensor by optical system imaging, and CCD or cmos image sensor are very responsive to infrared ray, undesired signal can appear under ultrared influence, therefore, when lens optical system designs, can place a wave filter, wave filter is made up of an infrared ray cut filter or low-pass filter, to guarantee that CCD or cmos image sensor receive only visible light, avoid when normal photographing, producing interference, and then guaranteed image quality because of infrared ray.

The utility model content

The purpose of this utility model is to provide a kind of solution because of imageing sensor (as CCD or CMOS) sensitivity of Infrared to be caused bad image quality, simultaneously, adopt suitable optical texture, and aspheric surface is set on the surface of the suitable eyeglass of optical texture, and optical thin film and filtering functions are incorporated in the whole optical system, to improve the image capturing lens unit of image quality.

For achieving the above object, technical solution of the present utility model is: a kind of image capturing lens unit, its from object space be arranged in order to picture side into: first eyeglass, diaphragm, second eyeglass, prismatic glasses, the 4th eyeglass, diaphragm is between first eyeglass and second eyeglass.

Wherein first eyeglass has the forward refractive power, has a convex surface towards the thing side, and has an aspheric surface at least, this eyeglass is coated with anti-reflection film or has the optical thin film of filtering functions on the surface of thing side, be coated with anti-reflection film or have the optical thin film of filtering functions on the surface as side.

Wherein second eyeglass is a meniscus shape, its concave surface is towards the thing side, it has negative refractive power, and has an aspheric surface at least, this eyeglass is coated with anti-reflection film or has the optical thin film of filtering functions on the surface of thing side, be coated with anti-reflection film or have the optical thin film of filtering functions on the surface as side.

Wherein prismatic glasses for the bent moon profile have forward refracting power and its convex surface towards thing side and an aspheric surface thing side surface and an aspheric surface as side surface, this eyeglass is coated with anti-reflection film or has the optical thin film of filtering functions on the surface of thing side, be coated with anti-reflection film or have the optical thin film of filtering functions on the surface as side.

This system satisfies condition :-1.5≤(F1+F2)/F≤0.3, and wherein F1, F2 are the length of the effective focal length of first eyeglass in this optical system, second eyeglass, F is the length of the focal length of this optical system.

This system satisfies condition: 0.01＜| F1/F2|＜1, wherein F1 is the length of the effective focal length of first eyeglass in this optical system, F2 is the length of the effective focal length of second eyeglass in this system.

And the optical thin film with filtering functions can be coated on any one surface of all eyeglasses in the system, when being coated on first to the surface of prismatic glasses, then can save the 4th eyeglass.

Satisfy condition: 0.2＜D3/D5＜1.8 wherein D3 are second eyeglass towards the summit of the face of thing side to the distance of second eyeglass towards the summit of the face of picture side, and D5 is a prismatic glasses towards three summits, summit to the of the face of thing side towards the distance on the summit of the face of picture side.

Satisfy condition: D4/F＜0.3 wherein D4 is second eyeglass towards the summit of picture side mirror face to the distance of prismatic glasses towards the summit of the face of thing side.

Adopt the camera lens of said structure, (for example CCD or CMOS) is different with human eye in the sensitivity characteristic of different wave length light for digital image sensor, for showing normal images, must adjust the spectrum that enters sensor, we adopt to add in native system and adjust spectrum function, this function can realize by a stand-alone assembly, or be incorporated on the eyeglass.

Be coated with the penetrance of anti-reflection film, thereby obtain better imaging effect with the enhancing eyeglass.

Use aspheric surface, the optical system that can be us plays better effect on the rectification aberration, traditional design is will use more structural to remove to reduce various aberrations, we then only need lens structure seldom just can achieve the goal by aspheric surface, making like this that system architecture obtains simplifying, image quality is improved lifts a simple example, the light velocity imaging point that spherical reflector is accepted infinity has spherical aberration, and parabolic mirror is accepted the picture point that the light beam of infinity becomes and can be reduced the spherical aberration point.

Description of drawings

Fig. 1 is a structural representation of the present utility model.

Embodiment

Following with reference to the description of drawings embodiments of the invention, these figure only can help to understand on the degree of the present invention the shape of general description parts, size and configuration relation.In addition, below numerical value and other condition of using in the explanation only is suitable examples, and the present invention has more than the shape that is confined to these embodiment.

As shown in Figure 1, the arrangement to each assembly of picture side is followed successively by first eyeglass 1, diaphragm 5, second eyeglass 2, prismatic glasses 3, the 4th eyeglass 4 from object space in this system.Diaphragm 5 is between first eyeglass 1 and second eyeglass 2.Wherein first eyeglass 1 has the forward refractive power, has a convex surface to the thing side, and has an aspheric surface at least, this eyeglass is coated with anti-reflection film or has the optical thin film of filtering functions on the surface of thing side, be coated with anti-reflection film or have the optical thin film of filtering functions on the surface as side.Wherein second eyeglass 2 is a meniscus shape, its concave surface is towards the thing side, it has negative refractive power, and has an aspheric surface at least, this eyeglass is coated with anti-reflection film or has the optical thin film of filtering functions on the surface of thing side, be coated with anti-reflection film or have the optical thin film of filtering functions on the surface as side.Wherein prismatic glasses 3 for the bent moon profile have forward refracting power and its convex surface towards thing side and an aspheric surface thing side surface and an aspheric surface as side surface, this eyeglass is coated with anti-reflection film or has the optical thin film of filtering functions on the surface of thing side, be coated with anti-reflection film or have the optical thin film of filtering functions on the surface as side.

11 is the plane of incidence of

first eyeglass

1, and 12 is the exit facet of first eyeglass 1; 21 is the plane of incidence of second eyeglass 2, and 22 is the exit facet of second eyeglass 2; 31 is the plane of incidence of prismatic glasses 3, and 32 is the exit facet of prismatic glasses 3; 41 is the plane of incidence of the 4th eyeglass 4, and 42 is the exit facet of the 4th eyeglass 4; Assembly 6 is digital image sensor (for example CCD or CMOS) receiving plane.

The camera lens of said structure, (for example CCD or CMOS) is different with human eye in the sensitivity characteristic of different wave length light for digital image sensor, for showing normal images, must adjust the spectrum that enters sensor, we adopt to add in native system and adjust spectrum function, this function can realize by a stand-alone assembly, or be incorporated on the eyeglass.

Be coated with anti-reflection film with the penetrance that strengthens eyeglass, reduce the reflectivity of eyeglass, thereby obtain better imaging effect.

Use aspheric surface, the optical system that can be us plays better effect on the rectification aberration, traditional design is will use more structural to remove to reduce various aberrations, we then only need lens structure seldom just can achieve the goal by aspheric surface, making like this that system architecture obtains simplifying, image quality is improved lifts a simple example, the light velocity imaging point that spherical reflector is accepted infinity has spherical aberration, and can to reduce the spherical aberration point be no spherical aberration point and parabolic mirror is accepted picture point that the light beam of infinity becomes.

Enumerated concrete numerical value among the following embodiment based on the embodiment of said structure form.

Table 1:

Focal length value (EFFL): 3.82621
Focal length value (EFFL): 3.82621	Behind the optics burnt (BFL): 1.74
F/NO value: 2.8	Behind the optics burnt (BFL): 1.74
F/NO value: 2.8	Field of view angle (FOV): 60
Optics length overall (containing filter): 4.72	Field of view angle (FOV): 60

Table 2:

The surface sequence number	Radius-of-curvature (mm)	Thickness (mm)	Refractive index	Abbe number
The surface sequence number	Radius-of-curvature (mm)	Thickness (mm)	Refractive index	Abbe number	Object plane	Infinitely great	1200
11	1.468079	0.66	1.54	56.0	Object plane	Infinitely great	1200
11	1.468079	0.66			12	14.410228	0.09
Diaphragm	Infinitely great	0.59			12	14.410228	0.09
Diaphragm	Infinitely great	0.59	21	-0.956986	0.58	1.60	26.6
22	-1.669305	0.35	21	-0.956986	0.58
22	-1.669305	0.35	31	1.559020	0.71			1.50	56.0
32	1.838131	0.20	31	1.559020	0.71
32	1.838131	0.20	41	Infinitely great	0.70	1.51	64.1
42	Infinitely great	0.843324	41	Infinitely great	0.70
42	Infinitely great	0.843324	Image planes	Infinitely great

Table 3:

F	F1	F2	F3
F	F1	F2	F3	3.76192	2.90254	-7.12627	28.8062

Wherein meet the following conditions:

(F1+F2)/F=-1.1228 satisfies condition :-1.5≤(F1+F2)/F≤0.3

| F1/F2|=0.407 satisfies condition: 0.01＜| F1/F2|＜1

D3/D5=0.817 satisfies condition: 0.2＜D3/D5＜1.8

D4/F=0.093 satisfies condition: D4/F＜0.3

Wherein: the effective focal length of first eyeglass 1 is F1, and the effective focal length of second eyeglass 2 is F2, and the effective focal length of whole optical system is F; D3 is second eyeglass 2 towards the summit of the face of thing side to the distance of second eyeglass 2 towards the summit of the face of picture side, D5 be prismatic glasses 3 towards the summit of the face of thing side to the distance of prismatic glasses 3 towards the summit of the face of picture side, D4 is second eyeglass 2 towards the summit of picture side mirror face to the distance of prismatic glasses 3 towards the summit of the face of thing side.

Claims

1, a kind of image capturing lens unit is characterized in that: from object space be arranged in order to picture side into: first eyeglass, diaphragm, second eyeglass, prismatic glasses, the 4th eyeglass, diaphragm is between first eyeglass and second eyeglass.

2, a kind of image capturing lens unit as claimed in claim 1, it is characterized in that: wherein first eyeglass has the forward refractive power, has a convex surface towards the thing side, and has an aspheric surface at least, this eyeglass is coated with anti-reflection film or has the optical thin film of filtering functions on the surface of thing side, be coated with anti-reflection film or have the optical thin film of filtering functions on the surface as side.

3, a kind of image capturing lens unit as claimed in claim 1, it is characterized in that: wherein second eyeglass is a meniscus shape, its concave surface is towards the thing side, it has negative refractive power, and has an aspheric surface at least, this eyeglass is coated with anti-reflection film or has the optical thin film of filtering functions on the surface of thing side, be coated with anti-reflection film or have the optical thin film of filtering functions on the surface as side.

4, a kind of image capturing lens unit as claimed in claim 1, it is characterized in that: wherein prismatic glasses for the bent moon profile have forward refracting power and its convex surface towards thing side and an aspheric surface thing side surface and an aspheric surface as side surface, this eyeglass is coated with anti-reflection film or has the optical thin film of filtering functions on the surface of thing side, be coated with anti-reflection film or have the optical thin film of filtering functions on the surface as side.

5, as claim 1,2 or 3 described a kind of image capturing lens units, it is characterized in that: this system satisfies condition :-1.5≤(F1+F2)/F≤0.3, wherein F1, F2 are the length of the effective focal length of first eyeglass in this optical system, second eyeglass, and F is the length of the focal length of this optical system.

6, as claim 1,2 or 3 described a kind of image capturing lens units, it is characterized in that: this system satisfies condition: 0.01＜| F1/F2|＜1, wherein F1 is the length of the effective focal length of first eyeglass in this optical system, and F2 is the length of the effective focal length of second eyeglass in this system.

7, as claim 1,3 or 4 described a kind of image capturing lens units, it is characterized in that: satisfy condition: 0.2＜D3/D5＜1.8 wherein D3 are second eyeglass towards the summit of the face of thing side to the distance of second eyeglass towards the summit of the face of picture side, D5 be prismatic glasses towards three summits, summit to the of the face of thing side towards the distance on the summit of the face of picture side.

8, as claim 1,3 or 4 described a kind of image capturing lens units, it is characterized in that: satisfy condition: D4/F＜0.3 wherein D4 is second eyeglass towards the summit of picture side mirror face to the distance towards the summit of the face of thing side of prismatic glasses.

9, image capturing lens unit as claimed in claim 1, it is characterized in that: the optical thin film that wherein has filtering functions can be coated on any one surface of all eyeglasses in the system, when it is coated on first to the surface of prismatic glasses the time, then can save the 4th eyeglass.