CN2725919Y - Short focus big view field camera lens - Google Patents

Abstract

The utility model discloses a pick-up lens with a short focus and large field of vision. The utility model is mainly characterized in that the pick-up lens is composed of four pieces of lenses and a light diaphragm, wherein based on the foundation of a reflection far object lens, the four pieces of lenses are counted from object space; consequently, the first piece is a falcate negative lens which enables an included angle formed by a mainshaft and a light beam which is outside the shaft and passes through the negative lenses to be greatly reduced, and the rest three pieces form a group are object lenses and enlarge a relative aperture, image illumination is caused to be slowly reduced, and basic uniformity is realized. The utility model has the outstanding advantages of image improvement, high image definition, uniform illumination, cost reduction, good performance, etc.

Description

Short burnt large-field shooting camera lens

Technical field:

The utility model belongs to the optical instrument technical field, is the burnt large-field shooting camera lens of a kind of weak point.

Background technology:

It is low that the burnt large-field shooting camera lens of existing weak point exists imaging definition, and the limit of visual field looks like to have dark angle, and the burnt large-field shooting camera lens of this weak point also is mainly derived from import, the material price height that it is selected, therefore, exist and cost an arm and a leg, it is not enough that product quality can not meet the demands etc.

Summary of the invention:

The purpose of this utility model is the burnt large-field shooting camera lens of design a kind of imaging weak point clear, that illumination is even, cost is low.

For reaching above-mentioned purpose, the main technical schemes that the utility model is taked is: have microscope base, end cap, it is characterized in that in microscope base, being provided with four object lens and a fixed aperture, based on the reflection type object lens far away the basis on from the object space number, first object lens one is the bent moon negative lens, an outer light beam is reduced greatly with angle of main shaft inclination behind negative lens, the back group is three lens objective, object lens two are the biconvex positive lens, object lens three are the biconvex positive lens, and object lens four are the convex-concave negative lens, and fixed aperture is between object lens one and object lens two.Group has improved relative aperture after three.Field ray is reduced greatly through the pitch angle of system and main shaft.

Optical characteristics: focal length F=3.66mm, field angle 2W=106 °, relative aperture F=2.4, rear cut-off distance LF=5.7mm.Above-mentioned object lens, fixed aperture satisfy following data:

Structural parameters: radius r thickness d material n

Object lens one 8.4～8.9

2.6～3.0 0.5～1 nd＝1.64?vd＝60.1

Diaphragm 0 6.8～7.3

Object lens 2 40～50 0.1～0.4

-6～-6.4 3.8～4.2 nd＝1.62 vd＝60.3

Object lens 3 6～6.5 0.1～0.4

-4.5～-4.8 2.5～3.0 nd＝1.62 vd＝60.3

Object lens four-4.6～-4.9 0～0.05

-60～-80 0.2～1 nd＝1.85 vd＝23.8

According to the burnt large-field shooting camera lens of weak point that such scheme is made, when the optical transfer function mtf value was 601p/mm in spatial frequency, the center reached 0.6, and the edge reaches 0.2.The bright effect of visual field codamine, field of view edge relative exposure have and can improve imaging greater than 60%, the imaging definition height, and illumination is even, can reduce cost remarkable advantages such as function admirable.

Reach example in conjunction with the accompanying drawings and further describe specific embodiments of the present utility model.

Description of drawings:

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

Fig. 2 is the embodiment synoptic diagram of utility model.

Embodiment:

Referring to Fig. 1, the short burnt large-field shooting camera lens of the utility model comprises: end cap 1, microscope base 2, spacer ring 3, spacer ring 4, object lens 45, object lens 36, object lens 27, object lens 1.Object lens 1, object lens 27, object lens 36, object lens 45 are by spacer ring 3, and spacer ring 4 is contained in the microscope base 2, and the front end of object lens 1 is equipped with end cap 1.

Referring to Fig. 2, from object space, object lens 1 are the bent moon negative lens, are positioned at the top of camera lens; Object lens 27 are the biconvex positive lens, and object lens 36 are the biconvex positive lens, and object lens 45 are the convex-concave negative lens, and said diaphragm is between object lens 1 and object lens 27.

Optical characteristics: focal length F=3.66mm, field angle 2W=106 °, relative aperture F=2.4, the above-mentioned object lens of rear cut-off distance LF=5.7mm, fixed aperture satisfy following data:

Concrete structure data one:

Radius r thickness d material n

Object lens one R ₁8.4

R ₂?2.6 0.5 nd＝1.64?vd＝60.1

Diaphragm 0 6.8

Object lens two R ₃40 0.1

R ₄?-6 3.8 nd＝1.62?vd＝60.3

Object lens three R ₅6 0.1

R ₆?-4.5 2.5 nd＝1.62?vd＝60.3

Object lens four R ₇-4.6 0.01

R ₈?-60 0.2 nd＝1.85?vd＝23.8

Concrete structure data two:

Radius r thickness d material n

Object lens one R ₁8.9

R ₂?3.0 1.0 nd＝1.64?vd＝60.1

Diaphragm 0 7.3

Object lens two R ₃50 0.4

R ₄?-6.4 4.2 nd＝1.62?vd＝60.3

Object lens three R ₅6.5 0.4

R ₆?-4.8 3.0 nd＝1.62?vd＝60.3

Object lens four R ₇-4.9 0.05

R ₈?-80 1.0 nd＝1.85?vd＝23.8。

Claims (3)

1, the burnt large-field shooting camera lens of a kind of weak point, has microscope base [2], end cap [1] is characterized in that being provided with four object lens and a diaphragm in microscope base [2], from the object space number, first object lens one [8] is the bent moon negative lens, be positioned at camera lens top, object lens two [7] are the biconvex positive lens, and object lens three [6] are the biconvex positive lens, object lens four [5] are the convex-concave negative lens, and diaphragm is between object lens one [8] and object lens two [7].

2,, it is characterized in that described camera lens meets the following conditions: focal length F=3.66mm, field angle 2W=106 °, relative aperture F=2.4, rear cut-off distance LF=5.7mm according to the burnt large-field shooting camera lens of a kind of weak point of claim 1.

3,, it is characterized in that described camera lens meets the following conditions according to the burnt large-field shooting camera lens of a kind of weak point of claim 1:

Structural parameters: radius r thickness d material n

Object lens one 8.4～8.9

2.6～3.0 0.5～1 nd＝1.64 vd＝60.1

Diaphragm 0 6.8～7.3

Object lens 40～50 0.1～0.4

-6～-6.4 3.8～4.2 nd＝1.62 vd＝60.3

Object lens 3 6～6.5 0.1～0.4

-4.5～-4.8 2.5～3.0 nd＝1.62 vd＝60.3

Object lens four-4.6～-4.9 0～0.05

-60～-80 0.2～1 nd＝1.85 vd＝23.8。

Images