CN115145004A - Combined lens group and lens - Google Patents

Abstract

The invention relates to the technical field of lens design, and relates to a combined lens group and a lens, wherein the combined lens group includes a first lens group, a second lens group, a third lens group and a fourth lens group arranged in sequence along the incident light path and a fifth lens group; the first lens group is a lens with negative refractive power, the second lens group is a lens with positive refractive power, and the third lens group is a lens with negative refractive power, The fourth lens group is a lens with positive refractive power, and the fifth lens group is a lens with negative refractive power. This lens is mainly used in AOI equipment. It uses long back focus to provide high magnification for crystal surface defect detection. It has the characteristics of small chromatic aberration and distortion and high detection accuracy.

Description

A combined lens group and lens

technical field

The invention relates to the technical field of lens design, in particular to a combined lens group and a lens.

Background technique

With the development of multimedia technology, electronic products with photographic or optical visual inspection functions are more and more favored by consumers, such as cameras and AOI equipment for crystal surface defect detection High precision products in applications. Among them, the optical lens in the AOI equipment is an important structure for imaging.

The existing optical lenses have the following shortcomings: 1. The lenses used in the current large-aperture photography are basically divided into spherical lenses and aspherical lenses. The spherical lenses are used for large-diameter optical wide-angle lenses. The aberration and deformation are relatively large, resulting in The imaging effect is poor, the cost of aspherical lenses is very high, and the production technology is basically monopolized by foreign countries; 2. Most of the existing standard lenses adopt the overall mobile focusing or front group focusing methods, and the overall mobile focusing or front group focusing methods are adopted. The focusing method is prone to the phenomenon of head down; 3. When the photographic lenses on the market are used for video recording, there will be a serious "breathing effect", and the "breathing effect" will change the angle of view during continuous focusing. The method is a multi-group moving focusing method, but the multi-group moving focusing method requires very high requirements on structural design, machining and assembly accuracy, and the current domestic processing level has not been met; 4. In the case of large aperture ratios, such as The optical elements and optical apertures on the surface side are likely to increase in size in the radial direction, and the configuration of the refraction power of the wide-angle optical system is asymmetric before and after, which is prone to vertical-axis chromatic aberration and distortion.

SUMMARY OF THE INVENTION

The present invention provides a combined lens group and a lens, which solve the technical problems that the above-mentioned chromatic aberration and distortion of the lens cannot be solved.

The present invention provides a combined lens group to solve the above-mentioned technical problems, comprising: a first lens group, a second lens group, a third lens group, a fourth lens group and a fifth lens group arranged in sequence along the incident light path ;

The first lens group is a lens with negative refractive power, the second lens group is a lens with positive refractive power, the third lens group is a lens with negative refractive power, and the fourth lens group is a lens with negative refractive power. is a lens with positive refractive power, and the fifth lens group is a lens with negative refractive power.

Preferably, the first lens group includes a snap mirror for reducing spherical aberration, expanding the field of view, and increasing incident light.

Preferably, the second lens group includes a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens arranged in sequence along the incident light path.

Preferably, the third lens group includes a seventh lens and an eighth lens arranged in sequence along the incident light path.

Preferably, the fourth lens group includes a ninth lens, a tenth lens and an eleventh lens arranged in sequence along the incident light path, and the ninth lens, the tenth lens and the eleventh lens are all cemented lenses, It is used to balance the chromatic aberration and spherical aberration of the third lens group and the fifth lens group.

Preferably, the fifth lens group includes a twelfth lens for correcting field curvature.

Preferably, a diaphragm for correcting field curvature to optimize the fringe field of view is provided between the third lens group and the fourth lens group.

Preferably, the first lens group, the second lens group, the third lens group, the fourth lens group and the fifth lens group are coaxially arranged.

The present invention also provides a lens, comprising the aforementioned combined lens group;

The lens further includes a lens barrel, a receiving cavity is arranged in the lens barrel, and the combined lens group is fixed in the receiving cavity.

Beneficial effects: The present invention provides a combined lens group and a lens, wherein the combined lens group includes a first lens group, a second lens group, a third lens group, a fourth lens group and a Five lens groups; the first lens group is a lens with negative refractive power, the second lens group is a lens with positive refractive power, the third lens group is a lens with negative refractive power, the The fourth lens group is a lens with positive refractive power, and the fifth lens group is a lens with negative refractive power. This lens is mainly used in AOI equipment. It uses long back focus to provide high magnification for crystal surface defect detection. It has the characteristics of small chromatic aberration and distortion and high detection accuracy.

The above description is only an overview of the technical solution of the present invention. In order to understand the technical means of the present invention more clearly, and implement it according to the content of the description, the preferred embodiments of the present invention are described in detail below with the accompanying drawings. Specific embodiments of the present invention are given in detail by the following examples and the accompanying drawings.

Description of drawings

The accompanying drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the attached image:

FIG. 1 is a schematic diagram of the structure of the combined lens group of the present invention.

Description of reference numbers:

First lens 1, second lens 2, third lens 3, fourth lens 4, fifth lens 5, sixth lens 6, seventh lens 7, eighth lens 8, ninth lens 9, tenth lens 10, The eleventh lens 11 , the twelfth lens 12 , and the diaphragm 13 .

Detailed ways

The principles and features of the present invention will be described below with reference to the accompanying drawings. The examples are only used to explain the present invention, but not to limit the scope of the present invention. The invention is described in more detail by way of example in the following paragraphs with reference to the accompanying drawings. The advantages and features of the present invention will become apparent from the following description and claims. It should be noted that, the accompanying drawings are all in a very simplified form and in inaccurate scales, and are only used to facilitate and clearly assist the purpose of explaining the embodiments of the present invention.

It should be noted that when a component is referred to as being "fixed to" another component, it can be directly on the other component or there may also be a centered component. When a component is considered to be "connected" to another component, it may be directly connected to the other component or there may be a co-existence of an intervening component. When a component is considered to be "set on" another component, it may be directly set on the other component or there may be a co-existing centered component. The terms "vertical," "horizontal," "left," "right," and similar expressions are used herein for illustrative purposes only.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terms used herein in the description of the present invention are for the purpose of describing specific embodiments only, and are not intended to limit the present invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

As shown in FIG. 1 , the present invention provides a combined lens group and a lens, wherein the combined lens group includes a first lens group, a second lens group, a third lens group, and a fourth lens arranged in sequence along the incident light path and a fifth lens group; the first lens group is a lens with negative refractive power, the second lens group is a lens with positive refractive power, and the third lens group is a lens with negative refractive power , the fourth lens group is a lens with positive refractive power, and the fifth lens group is a lens with negative refractive power. This lens is mainly used in AOI equipment. It uses long back focus to provide high magnification for crystal surface defect detection. It has the characteristics of small chromatic aberration and distortion and high detection accuracy.

In a preferred solution, the first lens group includes a snap mirror for reducing spherical aberration, expanding the field of view, and increasing incident light. The alignment mirror is the first lens 1 shown in FIG. 1 . Used to reduce spherical aberration, expand the field of view, and increase incoming light.

In a preferred solution, the second lens group includes a second lens 2 , a third lens 3 , a fourth lens 4 , a fifth lens 5 and a sixth lens 6 arranged in sequence along the incident light path. It is used to correct the chromatic aberration produced by the first group and compensate the spherical aberration and chromatic aberration produced by the third group.

In a preferred solution, the third lens group includes a seventh lens 7 and an eighth lens 8 arranged in sequence along the incident light path. It is used to correct the coma generated by the second lens group and compensate the distortion of the first lens group.

In a preferred solution, the fourth lens group includes a ninth lens 9 , a tenth lens 10 and an eleventh lens 11 arranged in sequence along the incident light path. The ninth lens 9 , the tenth lens 10 and the eleventh lens The lenses 11 are all cemented lenses, which are used to balance the chromatic aberration and spherical aberration of the third lens group and the fifth lens group. Used to balance the chromatic aberration and spherical aberration generated by the third and fifth groups.

In a preferred solution, the fifth lens group includes a twelfth lens 12 for correcting field curvature. Used to correct field curvature.

Further, 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, the eighth lens 8, the ninth lens 9, the tenth lens The surface dimensions of the twelve lenses of lens 10, eleventh lens 11, and twelfth lens 12 are shown in the following table:

In a preferred solution, a diaphragm for correcting the curvature of field to optimize the fringe field of view is provided between the third lens group and the fourth lens group. The diaphragm is moved back, correcting the curvature of field to optimize the fringe field of view. The sixth lens 6, the seventh lens 7, the eighth lens 8, and the ninth lens 9 are added to reduce the blurring and optimize the fringe field of view.

In a preferred solution, the first lens group, the second lens group, the third lens group, the fourth lens group and the fifth lens group are coaxially arranged.

An embodiment of the present invention further provides a lens, including the aforementioned combined lens group; the lens further includes a lens barrel, and a receiving cavity is arranged in the lens barrel, and the combined lens group is fixed in the receiving cavity Inside. This lens is mainly used in AOI equipment, using long back focus to provide higher magnification for crystal surface flaw detection.

The above descriptions are only preferred embodiments of the present invention, and do not limit the present invention in any form; any person of ordinary skill in the industry can smoothly implement the present invention as shown in the accompanying drawings and the above descriptions. However, all those skilled in the art who are familiar with the technical solutions of the present invention make use of the above-disclosed technical content to make some changes, modifications and equivalent changes of evolution, all of which are equivalent implementations of the present invention. At the same time, any alteration, modification and evolution of any equivalent changes made to the above embodiments according to the essential technology of the present invention still fall within the protection scope of the technical solutions of the present invention.

Claims (9)

1. A combined lens group, comprising: a first lens group, a second lens group, a third lens group, a fourth lens group and a fifth lens group which are sequentially arranged along an incident light path;

the first lens group is a lens with negative focal power, the second lens group is a lens with positive focal power, the third lens group is a lens with negative focal power, the fourth lens group is a lens with positive focal power, and the fifth lens group is a lens with negative focal power.

2. The combination lens group of claim 1, wherein the first lens group comprises a aplanatic lens for reducing spherical aberration, enlarging a field of view, and adding light.

3. The combined lens group of claim 1, wherein the second lens group comprises a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens arranged in that order along an incident light path.

4. The combined lens group of claim 1, wherein the third lens group comprises a seventh lens and an eighth lens arranged in sequence along an incident light path.

5. The combined lens group of claim 1, wherein the fourth lens group comprises a ninth lens, a tenth lens and an eleventh lens arranged in sequence along an incident light path, and the ninth lens, the tenth lens and the eleventh lens are all cemented lenses for balancing chromatic aberration and spherical aberration of the third lens group and the fifth lens group.

6. The combined lens group according to claim 1, wherein the fifth lens group comprises a twelfth lens for correcting curvature of field.

7. The combined lens group of claim 1, wherein a stop is disposed between the third lens group and the fourth lens group to correct curvature of field to optimize marginal field of view.

8. The combined lens group of claim 1, wherein the first lens group, the second lens group, the third lens group, the fourth lens group, and the fifth lens group are coaxially disposed.

9. A lens barrel comprising the combined lens group according to any one of claims 1 to 8;

the lens further comprises a lens barrel, a containing cavity is arranged in the lens barrel, and the combined lens group is fixed in the containing cavity.

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