Combined lens group and lens

Abstract

The present invention relates to the field of lens design technology, specifically a combined lens group and lens. The combined lens group comprises a first lens group, a second lens group, a third lens group, a fourth lens group, and a fifth lens group, arranged sequentially along the path of incident light. The first lens group comprises lenses with negative optical power, the second lens group comprises lenses with positive optical power, the third lens group comprises lenses with negative optical power, the fourth lens group comprises lenses with positive optical power, and the fifth lens group comprises lenses with negative optical power. This lens is primarily used in AOI equipment, utilizing a long back focus to provide high magnification for crystal surface defect detection. It exhibits minimal chromatic aberration and distortion, and high detection accuracy.

Description

Technical Field

[0001] The present invention relates to the technical field of lens design, and in particular to a combined lens group and a lens. Background Art

[0002] With the development of multimedia technology, electronic products with camera or optical visual inspection functions are becoming increasingly popular among consumers. For example, cameras and AOI equipment used for crystal surface defect detection have become high-precision products widely used in people's lives and industrial applications. The optical lens in AOI equipment is a key imaging structure.

[0003] Existing optical lenses have the following shortcomings: 1. Lenses currently used for large-aperture photography are generally divided into spherical and aspherical lenses. Spherical lenses used in wide-angle optical lenses with large apertures have relatively large aberrations and distortions, resulting in poor imaging quality. On the other hand, aspherical lenses are very expensive, and their production technology is largely monopolized by foreign countries. 2. Most existing standard lenses use either integral motion focusing or front-group focusing, which are prone to drooping. 3. Commercially available photographic lenses exhibit a severe "breathing effect" when used for video recording. This "breathing effect" causes the viewing angle to change during continuous focusing. The current mainstream method to eliminate this breathing effect is multi-group motion focusing, but this method requires very high structural design, machining, and assembly precision, which are currently not met by domestic processing capabilities. 4. With large aperture ratios, the optical elements and optical aperture on the image side tend to become radially enlarged, and the refractive power of the wide-angle optical system is asymmetrical in configuration, which is prone to vertical axial chromatic aberration and distortion. Summary of the Invention

[0004] The present invention provides a combined lens group and a lens, which solve the technical problems that cannot be solved by the chromatic aberration and distortion of the lens mentioned above.

[0005] In order to solve the above technical problems, the present invention provides 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 arranged in sequence along the path of incident light;

[0006] The first lens group is a lens with negative optical power, the second lens group is a lens with positive optical power, the third lens group is a lens with negative optical power, the fourth lens group is a lens with positive optical power, and the fifth lens group is a lens with negative optical power.

[0007] Preferably, the first lens group includes a z-ray lens for reducing spherical aberration, expanding the field of view, and increasing incident light.

[0008] 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.

[0009] Preferably, the third lens group includes a seventh lens and an eighth lens sequentially arranged along the incident light path.

[0010] Preferably, the fourth lens group includes a ninth lens, a tenth lens, and an eleventh lens sequentially arranged along the incident light path, and the ninth lens, the tenth lens, and the eleventh lens are all cemented lenses for balancing the chromatic aberration and spherical aberration of the third lens group and the fifth lens group.

[0011] Preferably, the fifth lens group includes a twelfth lens for correcting field curvature.

[0012] Preferably, a stop is provided between the third lens group and the fourth lens group for correcting field curvature to optimize the marginal field of view.

[0013] 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.

[0014] The present invention also provides a lens, comprising the combined lens group as described above;

[0015] The lens also includes a lens barrel, a receiving cavity is provided in the lens barrel, and the combined lens group is fixed in the receiving cavity.

[0016] Beneficial Effects: The present invention provides a combined lens group and 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 fifth lens group arranged sequentially along the path of incident light; the first lens group is a lens with negative optical power, the second lens group is a lens with positive optical power, the third lens group is a lens with negative optical power, the fourth lens group is a lens with positive optical power, and the fifth lens group is a lens with negative optical power. This lens is mainly used in AOI equipment, utilizing a long back focus to provide a high magnification for crystal surface defect detection, and has the characteristics of low chromatic aberration and distortion, and high detection accuracy.

[0017] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and to implement it according to the contents of the description, the following preferred embodiments of the present invention are described in detail with reference to the accompanying drawings. The specific implementation methods of the present invention are given in detail by the following embodiments and the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this 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 drawings:

[0019] Figure 1 This is a structural principle diagram of the combined lens group of the present invention.

[0020] Description of reference numerals:

[0021] 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, eleventh lens 11, twelfth lens 12, and aperture 13. DETAILED DESCRIPTION

[0022] The principles and features of the present invention are described below with reference to the accompanying drawings. The examples given are only used to explain the present invention and are not intended to limit the scope of the present invention. The following paragraphs describe the present invention in more detail by way of example with reference to the accompanying drawings. The advantages and features of the present invention will become more apparent from the following description and claims. It should be noted that the drawings are all in a very simplified form and are not in exact proportions. They are only used to facilitate and clearly illustrate the purpose of the embodiments of the present invention.

[0023] It should be noted that when a component is referred to as being "fixed to" another component, it may be directly on the other component or there may also be a central component. When a component is considered to be "connected to" another component, it may be directly connected to the other component or there may also be a central component. When a component is considered to be "set on" another component, it may be directly set on the other component or there may also be a central component. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention pertains. The terms used in this specification of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0025] like Figure 1As shown, the present invention provides a combined lens group and 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 fifth lens group arranged in sequence along the incident light path; the first lens group is a lens with negative optical power, the second lens group is a lens with positive optical power, the third lens group is a lens with negative optical power, the fourth lens group is a lens with positive optical power, and the fifth lens group is a lens with negative optical power. This lens is mainly used in AOI equipment, utilizing a long back focus to provide high magnification for crystal surface defect detection, and has the characteristics of low chromatic aberration and distortion, and high detection accuracy.

[0026] In a preferred embodiment, the first lens group includes a spherical lens for reducing spherical aberration, expanding the field of view, and increasing the amount of incident light. Figure 1 The first lens 1 shown in the figure is used to reduce spherical aberration, expand the field of view, and increase the amount of light entering.

[0027] Preferably, 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, for correcting the chromatic aberration produced by the first lens group and compensating for the spherical aberration and chromatic aberration produced by the third lens group.

[0028] Preferably, the third lens group includes a seventh lens 7 and an eighth lens 8 sequentially arranged along the incident light path, for correcting the coma produced by the second lens group and compensating for the distortion of the first lens group.

[0029] In a preferred embodiment, 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 11 are all cemented lenses, and are used to balance the chromatic aberration and spherical aberration of the third and fifth lens groups. The fourth lens group is used to balance the chromatic aberration and spherical aberration generated by the third and fifth lens groups.

[0030] In a preferred embodiment, the fifth lens group includes a twelfth lens 12 for correcting field curvature.

[0031] Furthermore, the surface dimensions of the twelve lenses, namely, 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 10, the eleventh lens 11, and the twelfth lens 12, are shown in the following table:

[0032]

[0033]

[0034] In a preferred embodiment, an aperture is provided between the third and fourth lens groups to correct for field curvature and optimize the peripheral field of view. The aperture is moved backward to correct for field curvature and optimize the peripheral field of view. The addition of a sixth lens element 6, a seventh lens element 7, an eighth lens element 8, and a ninth lens element 9 reduces blur and optimizes the peripheral field of view.

[0035] In a preferred embodiment, the first lens group, the second lens group, the third lens group, the fourth lens group and the fifth lens group are coaxially arranged.

[0036] An embodiment of the present invention further provides a lens comprising the aforementioned combined lens assembly; the lens also includes a lens barrel having a receiving cavity within the barrel, and the combined lens assembly is fixed within the receiving cavity. This lens is primarily used in AOI equipment, utilizing its long back focus to provide a high magnification for crystal surface defect detection.

[0037] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any ordinary technician in this industry can smoothly implement the present invention as shown in the drawings and described above. However, any equivalent changes, modifications and evolutions made by technicians familiar with this profession without departing from the scope of the technical solution of the present invention using the technical content disclosed above are all equivalent embodiments of the present invention. At the same time, any equivalent changes, modifications and evolutions made to the above embodiments based on the essential technology of the present invention are still within the scope of protection of the technical solution of the present invention.

Claims

1. A combined lens assembly, characterized in that: The combined lens group consists of 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 optical power, the second lens group is a lens with positive optical power, the third lens group is a lens with negative optical power, the fourth lens group is a lens with positive optical power, and the fifth lens group is a lens with negative optical power; The distance between the second lens group and the third lens group is greater than the distance between the other lens groups; The fifth lens group consists of a twelfth lens for correcting field curvature; A stop is provided between the third lens group and the fourth lens group for correcting field curvature to optimize the peripheral field of view; The first lens group is composed of a Qiming lens for reducing spherical aberration, expanding the field of view and increasing the amount of light entering; The second lens group consists of a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens arranged in sequence along the incident light path; The third lens group consists of a seventh lens and an eighth lens arranged in sequence along the incident light path; The fourth lens group is composed of a ninth lens, a tenth lens, and an eleventh lens arranged in sequence along the incident light path. The ninth lens, the tenth lens, and the eleventh lens are all cemented lenses for balancing the chromatic aberration and spherical aberration of the third lens group and the fifth lens group. The surface dimensions of the twelve lenses, namely, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, the eighth lens, the ninth lens, the tenth lens, the eleventh lens, and the twelfth lens, are shown in the following table:

2. The combined lens assembly according to 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 arranged.

3. A lens, characterized in that: comprising the combined lens assembly according to any one of claims 1 to 2; The lens also includes a lens barrel, a receiving cavity is provided in the lens barrel, and the combined lens group is fixed in the receiving cavity.

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