CN204758908U - Optical lens with large aperture and large image surface - Google Patents

Abstract

The utility model discloses a big image plane optical lens of large aperture, including first lens, second lens, third lens, fourth lens, fifth lens, sixth lens, seventh lens and eighth lens, wherein first lens, second lens, third lens, fifth lens, sixth lens, seventh lens and eighth lens are plastic lens, effectively alleviate whole camera lens weight, and the fourth lens is glass lens, and the diaphragm is established in the middle of third lens and fourth lens, makes the utility model discloses big to F1.2 in camera lens aperture, the big to 1 inch in image forming image plane has satisfied simultaneously and can clearly shoot under the low light level environment to and the high camera shooting demand of its resolution ratio when the photo enlargies, the photo pixel of shooing reaches 2000 ten thousand-4000 ten thousand, can be used to camera lens fields such as cell-phone camera, surveillance camera.

Description

Optical lens with large aperture and large image surface

【Technical field】

The utility model relates to an optical lens, in particular to an optical lens with a large aperture and a large image surface.

【Background technique】

At present, there are some defects in the mobile phone and surveillance camera lens used, the aperture and the image surface are too small, such as the aperture is generally F2. Not enough tax profit, resulting in blurry photos when zoomed in.

The utility model is researched and proposed aiming at the deficiencies of the prior art.

【Content of utility model】

The technical problem to be solved by the utility model is to provide an optical lens with large aperture and large image surface, which includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens and a first lens. Eight lenses, the first lens, the second lens, the third lens, the fifth lens, the sixth lens, the seventh lens and the eighth lens are plastic lenses, which can effectively reduce the overall lens weight, and the fourth lens is a glass lens, and the light The aperture is set between the third lens and the fourth lens, so that the aperture of the lens of the utility model is as large as F1.2, and the imaging surface is as large as 1 inch. High-resolution cameras are required, and the pixels of the photos taken can reach 20-40 million, which can be used in mobile phone cameras, surveillance cameras and other lens fields.

In order to solve the above-mentioned technical problems, the utility model provides a large-aperture large-image-surface optical lens, which is provided with a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens in sequence from the object surface to the image surface. lens, the seventh lens, the eighth lens, a filter and a CMOS photosensitive chip, and an aperture is arranged between the third lens and the fourth lens.

The first lens is a plastic lens with a positive focal length, both sides of the first lens are hyperbolic aspheric surfaces, and the side facing the object plane is concave, and the side facing the image plane is convex.

The second lens is a negative focal length plastic lens, the side of the second lens facing the object plane is a hyperbolic aspheric surface, and the side facing the image plane is an ellipse or a hyperbolic aspheric surface.

The third lens is a plastic lens with a negative focal length, and both surfaces of the third lens are hyperbolic aspheric surfaces, and the side facing the object surface is convex, and the side facing the image surface is concave.

The fourth lens is a positive focal length glass lens, and both sides of the fourth lens are convex and hyperbolic aspheric.

The fifth lens is a plastic lens with a negative focal length, both sides of the fifth lens are hyperbolic aspheric surfaces, and the side facing the object plane is convex, and the side facing the image plane is concave.

The sixth lens is a plastic lens with a positive focal length, both surfaces of the sixth lens are hyperbolic aspheric surfaces, and the side facing the object plane is concave, and the side facing the image plane is convex.

The seventh lens is a plastic lens with a negative focal length and both surfaces are hyperbolic aspheric surfaces.

The eighth lens is a negative focal length lens and both surfaces are hyperbolic aspheric surfaces.

The focal lengths of the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens and the eighth lens are f1, f2, f3, f4, f5, f6, f7 and f8, the overall focal length of the first lens, the second lens and the third lens is f10, the overall focal length of the fourth lens, the fifth lens, the sixth lens, the seventh lens and the eighth lens is f20, and the The system element characteristics of the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens and the eighth lens satisfy: -5<f1/f2<0, -5<f4 /f5<0, f10<0, f20>0.

The overall focal length of the first lens, the second lens and the third lens is f10, and the dispersion coefficients of the fourth lens, the fifth lens, the sixth lens, the seventh lens and the eighth lens are vdlens1, vdlens2, vdlens3 respectively , vdlens4, vdlens5, vdlens6, vdlens7 and vdlens8, satisfying: 15<(vdlens2, vdlens3, vdlens5, vdlens8)<35, 82>(vdlens1, vdlens4, vdlens6, vdlens7)≥37.

The curvature corresponding to the radius of the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens and the eighth lens is c, and the first lens, the second lens The radial coordinates of the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens and the eighth lens are y2, y4, y6, y8, y10, y12, y14 and y16 respectively, and the first lens , The coefficients corresponding to the radial coordinates of the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens and the eighth lens are α1, α2, α3, α4, α5, α6, α7 and α8, the aspherical surface shapes of the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens and the eighth lens satisfy: Z=cy2/{1+[ 1-1+kc2y2] ^1/2 }+α1y2+α2y4+α3y6+α4y8+α5y10+α6y12+α7y14+α8y16.

The diaphragm is located at the center of the third lens and the fourth lens.

Compared with the prior art, the utility model has the following advantages:

1. The overall image surface of the utility model is uniform and high brightness, and the aperture number reaches F1.2.

2. The size of the image surface of the utility model is very large, reaching 1 inch or more.

3. Since the fourth lens in the present invention is a glass lens with a positive focal length and is an aspheric surface, the geometric transfer function of the optical system is greatly improved, and the efficiency and color reproduction of the lens product can be significantly improved.

4. The aperture is centered between the third lens and the fourth lens, so that the sensitivity of the lens of the present invention is greatly reduced, and the vertical axis chromatic aberration and distortion are significantly improved.

5. In the present invention, the first lens, the second lens, the third lens, the fifth lens, the sixth lens, the seventh lens and the eighth lens are plastic lenses, which can effectively reduce the overall weight of the lens.

【Description of drawings】

Below in conjunction with accompanying drawing, the specific embodiment of the present utility model is described in further detail, wherein:

Fig. 1 is a schematic diagram of the arrangement structure of each lens of the present invention.

【Detailed ways】

Below in conjunction with accompanying drawing, the embodiment of the present utility model is described in detail.

The utility model is an optical lens with large aperture and large image surface, which is sequentially provided with a first lens 1, a second lens 2, a third lens 3, a fourth lens 4, a fifth lens 5 and a sixth lens from the object surface to the image surface. 6. The seventh lens 7, the eighth lens 8, the optical filter 9 and the CMOS photosensitive chip 10, the light enters from the optical filter 9, the optical filter 9 has a certain protective effect on the CMOS photosensitive chip 10, and also filters a part Light to reduce stray light and spots, so that the image color is bright and sharp while having good color reproduction. A diaphragm 11 is provided between the third lens 3 and the fourth lens 4, and the diaphragm 11 is placed in the center, which can make the lens system of the present invention have a nearly symmetrical structure, thereby reducing aberration problems such as distortion and vertical chromatic aberration , effectively improve the imaging quality, and reduce the sensitivity and manufacturing difficulty of the lens at the same time.

The first lens 1 is a plastic lens with a positive focal length, both sides of the first lens 1 are hyperbolic aspheric surfaces, and the side facing the object plane is concave, and the side facing the image plane is convex.

The second lens 2 is a negative focal length plastic lens, the side of the second lens 2 facing the object plane is a hyperbolic aspheric surface, and the side facing the image plane is an ellipse or a hyperbolic aspheric surface.

The third lens 3 is a plastic lens with a negative focal length. Both sides of the third lens 3 are hyperbolic aspheric surfaces, and the side facing the object plane is convex, and the side facing the image plane is concave.

The fourth lens 4 is a positive focal length glass lens, and both sides of the fourth lens 4 are convex and hyperbolic aspheric.

The fifth lens 5 is a negative focal length plastic lens, both sides of the fifth lens 5 are hyperbolic aspheric surfaces, and the side facing the object plane is convex, and the side facing the image plane is concave.

The sixth lens 6 is a plastic lens with a positive focal length, both sides of the sixth lens 6 are hyperbolic aspheric surfaces, and the side facing the object plane is concave, and the side facing the image plane is convex.

The seventh lens 7 is a plastic lens with a negative focal length and both surfaces are hyperbolic aspheric surfaces.

The eighth lens 8 is a negative focal length lens and both surfaces are hyperbolic aspheric surfaces.

The focal lengths of the first lens 1, the second lens 2, the third lens 3, the fourth lens 4, the fifth lens 5, the sixth lens 6, the seventh lens 7 and the eighth lens 8 are f1, f2, f3, f4, f5, f6, f7 and f8, the overall focal length of the first lens 1, the second lens 2 and the third lens 3 is f10, the fourth lens 4, the fifth lens 5, the sixth lens 6, the first lens The overall focal length of the seven lenses 7 and the eighth lens 8 is f20, and the first lens 1, the second lens 2, the third lens 3, the fourth lens 4, the fifth lens 5, the sixth lens 6, and the seventh lens 7 And the system element characteristic of the eighth lens 8 satisfies: -5<f1/f2<0, -5<f4/f5<0, f10<0, f20>0, this structure can solve the large aperture and large image surface introduction of the utility model Aberrations such as spherical aberration and astigmatism.

The overall focal length of the first lens 1, the second lens 2 and the third lens 3 is f10, the dispersion of the fourth lens 4, the fifth lens 5, the sixth lens 6, the seventh lens 7 and the eighth lens 8 The coefficients are vdlens1, vdlens2, vdlens3, vdlens4, vdlens5, vdlens6, vdlens7 and vdlens8, satisfying: 15<(vdlens2, vdlens3, vdlens5, vdlens8)<35, 82>(vdlens1, vdlens4, vdlens6, vdlens7)≥37. With the above design, the problem of excessive axial chromatic aberration of the system can be solved, so as to achieve central high resolution.

The curvature corresponding to the radius of the first lens 1, the second lens 2, the third lens 3, the fourth lens 4, the fifth lens 5, the sixth lens 6, the seventh lens 7 and the eighth lens 8 is c, so The radial coordinates of the first lens 1, the second lens 2, the third lens 3, the fourth lens 4, the fifth lens 5, the sixth lens 6, the seventh lens 7 and the eighth lens 8 are y2, y4, y6 respectively , y8, y10, y12, y14 and y16, the first lens 1, the second lens 2, the third lens 3, the fourth lens 4, the fifth lens 5, the sixth lens 6, the seventh lens 7 and the eighth lens The coefficients corresponding to the radial coordinates of the lens 8 are α1, α2, α3, α4, α5, α6, α7 and α8, the first lens 1, the second lens 2, the third lens 3, the fourth lens 4, the first lens Five lens 5, sixth lens 6, seventh lens 7 and eighth lens 8 aspheric surface shape satisfy: Z=cy2/{1+[1-1+kc2y2] ^1/2 }+α1y2+α2y4+α3y6+α4y8 +α5y10+α6y12+α7y14+α8y16.

When the k coefficient is less than -1, the surface curve of the lens is a hyperbola; when the k coefficient is equal to -1, the lens' surface curve is a parabola; when the k coefficient is between -1 and 0, the lens' surface curve is The curve is an ellipse; when the k coefficient is equal to 0, the surface curve of the lens is circular; when the k coefficient is greater than 0, the surface curve of the lens is oblate.

Claims (4)

1. a large aperture large image surface optical lens is characterized in that the first lens (1), the second lens (2), the third lens (3), the fourth lens (4) are arranged successively from the object plane to the image surface ), the fifth lens (5), the sixth lens (6), the seventh lens (7), the eighth lens (8), the optical filter (9) and the CMOS photosensitive chip (10), the third lens ( 3) An aperture (11) is provided between the fourth lens (4); The first lens (1) is a positive focal length plastic lens, both sides of the first lens (1) are hyperbolic aspheric surfaces, and the side facing the object surface is concave, and the side facing the image surface is convex; The second lens (2) is a negative focal length plastic lens, the side of the second lens (2) facing the object plane is a hyperbolic aspheric surface, and the side facing the image surface is an ellipse or a hyperbolic aspheric surface; The third lens (3) is a plastic lens with a negative focal length, both sides of the third lens (3) are hyperbolic aspheric surfaces, and the side facing the object surface is a convex surface, and the side facing the image surface is a concave surface; The fourth lens (4) is a positive focal length glass lens, and both sides of the fourth lens (4) are convex and hyperbolic aspheric surfaces; The fifth lens (5) is a negative focal length plastic lens, both sides of the fifth lens (5) are hyperbolic aspheric surfaces, and the side facing the object surface is convex, and the side facing the image surface is concave; The sixth lens (6) is a positive focal length plastic lens, both sides of the sixth lens (6) are hyperbolic aspheric surfaces, and the side facing the object surface is concave, and the side facing the image surface is convex; The seventh lens (7) is a negative focal length plastic lens and both sides are hyperbolic aspheric surfaces; The eighth lens (8) is a negative focal length lens and both surfaces are hyperbolic aspheric surfaces. 2. A kind of optical lens with large aperture and large image surface according to claim 1, characterized in that the first lens (1), the second lens (2), the third lens (3), the fourth lens (4) , the focal lengths of the fifth lens (5), the sixth lens (6), the seventh lens (7) and the eighth lens (8) are f1, f2, f3, f4, f5, f6, f7 and f8, the first The overall focal length of a lens (1), second lens (2) and third lens (3) is f10, and the fourth lens (4), fifth lens (5), sixth lens (6), seventh lens The overall focal length of the lens (7) and the eighth lens (8) is f20, the first lens (1), the second lens (2), the third lens (3), the fourth lens (4), the fifth lens (5), the system element characteristics of the sixth lens (6), the seventh lens (7) and the eighth lens (8) satisfy: -5<f1/f2<0, -5<f4/f5<0, f10< 0, f20>0; The overall focal length of the first lens (1), the second lens (2) and the third lens (3) is f10, and the fourth lens (4), the fifth lens (5), and the sixth lens (6) The dispersion coefficients of the seventh lens (7) and the eighth lens (8) are vdlens1, vdlens2, vdlens3, vdlens4, vdlens5, vdlens6, vdlens7 and vdlens8 respectively, satisfying: 15<(vdlens2, vdlens3, vdlens5, vdlens8)<35 , 82>(vdlens1, vdlens4, vdlens6, vdlens7)≥37. 3. according to claim 1 or 2 described a kind of optical lens with large aperture and large image surface, it is characterized in that the first lens (1), the second lens (2), the third lens (3), the fourth lens ( 4), the curvature corresponding to the radius of the fifth lens (5), the sixth lens (6), the seventh lens (7) and the eighth lens (8) is c, and the first lens (1), the second lens (2), the third lens (3), the fourth lens (4), the fifth lens (5), the sixth lens (6), the seventh lens (7) and the eighth lens (8) radial coordinates are respectively y2, y4, y6, y8, y10, y12, y14 and y16, the first lens (1), the second lens (2), the third lens (3), the fourth lens (4), the fifth lens ( 5), the coefficients corresponding to the radial coordinates of the sixth lens (6), the seventh lens (7) and the eighth lens (8) are α1, α2, α3, α4, α5, α6, α7 and α8, said The first lens (1), the second lens (2), the third lens (3), the fourth lens (4), the fifth lens (5), the sixth lens (6), the seventh lens (7) and the The aspherical surface shape of the eight lenses (8) satisfies: Z=cy2/{1+[1-(1+k)c2y2] ^1/2 }+α1y2+α2y4+α3y6+α4y8+α5y10+α6y12+α7y14+α8y16. 4 . The optical lens with large aperture and large image surface according to claim 3 , characterized in that the diaphragm ( 11 ) is located at the center of the third lens ( 3 ) and the fourth lens ( 4 ).