CN201892780U

CN201892780U - CaF2-free low-power plan apochromatic metallographic microscope

Info

Publication number: CN201892780U
Application number: CN201020648949XU
Authority: CN
Inventors: 萧泽新; 曹杰; 李鹏; 肖冉
Original assignee: Guilin University of Electronic Technology
Current assignee: Guilin University of Electronic Technology
Priority date: 2010-12-07
Filing date: 2010-12-07
Publication date: 2011-07-06
Anticipated expiration: 2020-12-07

Abstract

The utility model provides a CaF2-free low-power plan apochromatic metallographic microscope, comprising lenses. The CaF2-free low-power plan apochromatic metallographic microscope is characterized by consisting of three lenses, i.e. a first positive lens, a second negative lens and a third positive lens which are coaxial and are sequentially arranged from left to right as follows: the first positive lens->the second negative lens->the third positive lens>an object plane, and the object plane->the third positive lens->the second negative lens->the first positive lens; and the formed image is at an infinite position. The CaF2-free low-power plan apochromatic metallographic microscope has the advantages that: 1, the CaF2-free low-power plan apochromatic metallographic microscope achieves the plan apochromatic effect; 2, the working distance is long; 3, the cost performance is high; and 4, the structure is simple.

Description

No CaF＜sub〉2＜/sub〉low power flat field apochromatism metallography microscope object lens

Technical field

The utility model relates to microcobjective, particularly a kind of no CaF ₂Low power flat field apochromatism metallography microscope object lens.

Background technology

Microcobjective is the important composition parts of metaloscope, and the height of its image quality directly influences the performance of metaloscope.The flat field apochromatic micro objective is the microcobjective that picture element is best, class is the highest.For proofreading and correct axial chromatic aberration and second order spectrum simultaneously, conventional way is to introduce optical crystal in the part positive lens, as calcium fluoride CaF in object lens ₂Deng as manufactured materials.In recent years, the someone uses special glass (as TF ₃) substitute or partly alternative CaF ₂Manufacture and design the flat field apochromatic objective, shown superiority aspect the manufacturability reducing cost and improve, but the special optical material is few, more crisp, the physicochemical property instability, large-sized material more is difficult to obtain.External like product Germany Lay thatch object lens are made up of 5 lens, and Japanese Olympus is made up of 7 saturating sheets, and have all adopted and contain CaF ₂Material.

The utility model content

The purpose of this utility model is that a kind of no CaF will be provided ₂Low power flat field apochromatism metallography microscope object lens, this microcobjective has high performance-price ratio, and is simple in structure.

The utility model purpose realizes by following technical solution:

The utility model does not have CaF ₂It is prototype structure that low power flat field apochromatism metallography microscope object lens separate photographic lens with three, uses OSLO optical design CAD software, by the focal length convergent-divergent, optimizes r, d, and n (r is a spherical radius, and d is a thickness, and n is a refractive index) textural element has been designed no CaF ₂Low power flat field apochromatism metallography microscope object lens.These object lens are by first positive lens, and second negative lens, the 3rd positive lens totally three lens are formed, and three lens are coaxial, and from left to right putting in order is first positive lens → second negative lens → 3rd positive lens → object plane, its

Operating distance W.D＞30mm;

Enlargement ratio β=4 *-6.3 *;

Numerical aperture 〉=0.1; Aperture angle＞2 °;

Focal distance f '=38-65mm.

Described lens are not for containing CaF ₂The ordinary optical glass material.

The utility model does not have CaF ₂Low power flat field apochromatism metallography microscope object lens show through geometrical aberration evaluation and PTZ3 tables of data contrast test, reflecting intuitively that d, F, c light are with at 0.707 ω intersects at a point, the spherochromatism of three kinds of wavelength is also less, the flat field effect is also quite satisfied: as seen a thatch ten thousand curvature of field (PTZ3)=-0.003558 are quite outstanding optical textures.

The utility model has the advantages that:

1, do not contain CaF2 low power metallography microscope object lens, reach flat field apochromatism effect;

2, long reach;

3, cost performance height;

4, simple in structure.

Description of drawings

Fig. 1 is the utility model microcobjective structural representation;

Fig. 2 is the geometrical aberration evaluation map of the utility model microcobjective;

Fig. 3 is a PTZ3 tables of data of the present utility model.

Among the figure: 1. the 3rd positive lens 4. object planes of 2. second negative lenses 3. of first positive lens

Embodiment

With reference to Fig. 1, the utility model does not have CaF ₂Low power flat field apochromatism metallography microscope object lens are made up of first positive lens 1, second negative lens 2, the 3rd positive lens 3, first positive lens 1, second negative lens 2, the 3rd positive lens 3 are coaxial, from left to right put in order is 1 → the second negative lens 2 of first positive lens → the 3rd positive lens 3 → object plane 4, object plane 4 is through 2 → the first positive lenss 1 of 3 → the second negative lenses of the 3rd positive lens, and imaging at infinity.

Lens are not for containing CaF ₂The ordinary optical glass material.

The utility model does not have CaF ₂Low power flat field apochromatism metallography microscope object lens:

Operating distance W.D＞30mm;

Enlargement ratio β=4 *-6.3 *;

Numerical aperture 〉=0.1; Aperture angle＞2 °;

Focal distance f '=38-65mm.

Fig. 2 and Fig. 3 reflect intuitively that d, F, c light are with at 0.707 ω and intersect at a point that the spherochromatism of three kinds of wavelength is also less, and the flat field effect is also quite satisfied: as seen a thatch ten thousand curvature of field (PTZ3)=-0.003558 are quite outstanding optical textures.

Claims

1. no CaF ₂Low power flat field apochromatism metallography microscope object lens, comprise lens, it is characterized in that: these object lens by first positive lens, second negative lens, the 3rd positive lens totally three lens form, and three lens are coaxial, from left to right putting in order is first positive lens → second negative lens → 3rd positive lens → object plane, its operating distance W.D＞30mm; Enlargement ratio β=4 *-6.3 *; Numerical aperture 〉=0.1; Aperture angle＞2 °; Focal distance f '=38-65mm.

2. no CaF according to claim 1 ₂Low power flat field apochromatism metallography microscope object lens, it is characterized in that: described lens are not for containing CaF ₂The ordinary optical glass material.