阅读说明：本技术 一种0.5倍110mm物距高分辨率工业双远心镜头 (0.5-time 110mm object distance high-resolution industrial double telecentric lens ) 是由 魏雄斌 李俊攀 王方强 于 2019-11-22 设计创作，主要内容包括：本发明涉及一种0.5倍110mm物距高分辨率工业双远心镜头,包括主镜筒,所述主镜筒内沿光线入射方向自前向后依次设置有前组镜片、光阑及后组镜片,所述前组镜片依次为第一双凸透镜、第一正月牙形透镜、双凹透镜和第二正月牙形透镜密接的第一胶合组；所述后组镜片依次为第三正月牙形透镜、第四正月牙形透镜、第二双凸透镜和负月牙形透镜密接的第二胶合组。该镜头分辨率高于500万、畸变低于0.006%、能实现110mm近摄距。(The invention relates to a high-resolution industrial double-telecentric lens with the object distance of 0.5 times 110mm, which comprises a main lens barrel, wherein a front group of lenses, a diaphragm and a rear group of lenses are sequentially arranged in the main lens barrel from front to back along the light incidence direction, and the front group of lenses are sequentially a first bonding group formed by tightly connecting a first biconvex lens, a first regular crescent lens, a biconcave lens and a second regular crescent lens; the rear group lens is a second adhesive combination formed by tightly connecting a third positive crescent lens, a fourth positive crescent lens, a second biconvex lens and a negative crescent lens in sequence. The lens has the resolution higher than 500 ten thousand and the distortion lower than 0.006 percent, and can realize the close-up distance of 110 mm.)

1. A high-resolution industrial double-telecentric lens with the object distance of 0.5 times 110mm comprises a main lens barrel and is characterized in that a front group lens, a diaphragm and a rear group lens are sequentially arranged in the main lens barrel from front to back along the light incidence direction, and the front group lens is a first bonding group formed by tightly connecting a first biconvex lens, a first regular crescent lens, a biconcave lens and a second regular crescent lens in sequence; the rear group lens is a second adhesive combination formed by tightly connecting a third positive crescent lens, a fourth positive crescent lens, a second biconvex lens and a negative crescent lens in sequence.

2. The 0.5-times 110mm object distance high resolution industrial double telecentric lens according to the claim 1, wherein the air space between the first biconvex lens and the first regular crescent lens is 10 mm; the air space between the first positive crescent lens and the first gluing set is 0.64 mm.

3. The 0.5-fold 110mm object distance high resolution industrial double telecentric lens according to the claim 1, wherein the air space between the front group of lenses and the rear group of lenses is 28.29 mm; the air space between the front group of lenses and the diaphragm is 28.15 mm; and the air interval between the diaphragm and the rear group of lenses is 0.14 mm.

4. The 0.5-times 110mm object distance high resolution industrial double telecentric lens according to the claim 1, 2 or 3, wherein the air space between the third and the fourth positive crescent shaped lenses is 12.41 mm; and the air space between the fourth positive crescent lens and the second gluing set is 5.16 mm.

5. The 0.5-fold 110mm object distance high resolution industrial double telecentric lens according to claim 1, wherein the main lens barrel comprises a front lens barrel for mounting a first biconvex lens, a first regular crescent lens, a first cemented group, a third regular crescent lens and a fourth regular crescent lens, a rear lens barrel for mounting a second cemented group is connected to the rear end of the front lens barrel, and a threaded interface is arranged at the rear end of the rear lens barrel.

6. The 0.5-time 110mm object distance high resolution industrial double telecentric lens according to claim 5, wherein the front lens barrel is provided with a front chamber and a rear chamber which are communicated, the front end of the front chamber is screwed with a front pressing ring for locking the first biconvex lens, a front spacer ring is arranged between the first biconvex lens and the first regular crescent lens, the middle part of the front chamber is provided with a bearing surface for abutting against the periphery of the rear side of the second regular crescent lens, and the rear side wall of the front chamber is provided with a delustering thread; the diaphragm is installed at the front end of the rear cavity and located on the front side of the third regular crescent lens, a middle partition ring located between the third regular crescent lens and the fourth regular crescent lens is arranged in the rear cavity, and a middle pressing ring used for locking the fourth regular crescent lens is screwed at the rear end of the rear cavity.

7. The industrial double-telecentric lens with the object distance of 0.5 times and the resolution of 110mm according to claim 5 or 6, wherein a bearing surface for abutting against the periphery of the front side of the second biconvex lens is arranged in the rear lens barrel, and a rear pressing ring for pressing against the periphery of the rear side of the negative crescent lens is screwed on the rear part of the rear lens barrel.

Technical Field

The invention relates to a high-resolution industrial double telecentric lens with 0.5-time 110mm object distance.

Background

With the continuous development of the industrial detection field, the common industrial lens has the factors of variable magnification focusing, parallax, high distortion, large structural appearance and the like, and the telecentric lens has the advantages of constant magnification, no change along with the change of depth of field, no parallax, light and compact structural appearance and the like, so that more and more industrial detection fields rely on the industrial telecentric lens to replace the common industrial lens for visual detection: such as precision part measurement, plastic part measurement, electronic component measurement, glass product and medical part measurement, etc.

Disclosure of Invention

The invention aims to provide an industrial detection double telecentric lens which has the resolution higher than 500 ten thousand and the distortion lower than 0.006 percent and can realize the close range of 110mm for the field of industrial detection.

The technical scheme of the invention is as follows: a high-resolution industrial double-telecentric lens with the object distance of 0.5 times 110mm comprises a main lens barrel, wherein a front group lens, a diaphragm and a rear group lens are sequentially arranged in the main lens barrel from front to back along the light incidence direction, and the front group lens is a first bonding group formed by tightly connecting a first biconvex lens, a first regular crescent lens, a biconcave lens and a second regular crescent lens in sequence; the rear group lens is a second adhesive combination formed by tightly connecting a third positive crescent lens, a fourth positive crescent lens, a second biconvex lens and a negative crescent lens in sequence.

Further, the air space between the first biconvex lens and the first regular crescent lens is 10 mm; the air space between the first positive crescent lens 5 and the first adhesive combination is 0.64 mm.

Further, the air space between the front group of lenses and the rear group of lenses is 28.29 mm; the air space between the front group of lenses and the diaphragm 9 is 28.15 mm; the air space between the diaphragm 9 and the rear group of lenses is 0.14 mm.

Further, an air space between the third and fourth regular crescent lenses 10 and 12 is 12.41 mm; the air space between the fourth regular crescent lens 12 and the second cemented group is 5.16 mm.

Further, the main lens cone comprises a front lens cone for mounting the first biconvex lens 2, the first regular crescent lens 5, the first cemented group, the third regular crescent lens 10 and the fourth regular crescent lens 12, the rear end of the front lens cone is connected with a rear lens cone for mounting the second cemented group, and the rear end of the rear lens cone is provided with a threaded interface.

Furthermore, the front lens barrel is provided with a front cavity and a rear cavity which are communicated, the front end of the front cavity is in threaded connection with a front pressing ring for locking the first biconvex lens, a front space ring is arranged between the first biconvex lens and the first regular crescent lens, the middle part of the front cavity is provided with a bearing surface for abutting against the periphery of the rear side of the second regular crescent lens, and the side wall of the rear part of the front cavity is provided with an extinction thread; the diaphragm is installed at the front end of the rear cavity and located on the front side of the third regular crescent lens, a middle partition ring located between the third regular crescent lens and the fourth regular crescent lens is arranged in the rear cavity, and a middle pressing ring used for locking the fourth regular crescent lens is screwed at the rear end of the rear cavity.

Furthermore, a bearing surface used for being abutted to the periphery of the front side surface of the second biconvex lens is arranged in the rear lens barrel, and a rear pressing ring used for pressing the periphery of the rear side of the negative crescent lens is screwed at the rear part of the rear lens barrel.

Compared with the prior art, the invention has the following advantages: the double-telecentric lens is simple in structure and small in volume, can meet the industrial detection field of measurement of precision parts, plastic parts, electronic components, glass products, medical parts and the like, and provides a visual detection scheme with a more compact structure and a smaller volume for industrial detection.

The mechanical structure of the lens adopts a two-section butt joint forming structure, and the optical system reasonably distributes the focal power of the front and rear groups of the lens by elaborately selecting the front and rear groups of eight optical glass materials, so that the focal power of the system is further optimized, and the spherical aberration and chromatic aberration of the system are well corrected. Therefore, when the object distance of 110mm is realized, the MTF of the lens is more than or equal to 0.4 (as shown in figure 4) at 80lp/mm, the resolution is as high as 500 ten thousand pixels, and the optical distortion is less than 0.006 percent.

The mechanical structure of the lens adopts a two-section butt joint forming structure to effectively realize the coaxiality of the axes of the front and rear lens groups; in order to improve the space structure inside the lens, the diaphragm is provided with a built-in fixed diaphragm structure, so that the consistency of the lens diaphragm is improved, and the optical performance of the lens is further ensured; in order to reduce the influence of stray light and ghost on the imaging quality of the lens, the two spacing rings are designed to be supported and leaned by a step-shaped structure, so that the entering and the reflection of ineffective light rays are effectively reduced, and the stability of matching with the lens is improved; in order to further eliminate stray light and ghost images, an extinction thread structure is designed on the inner wall of the lens barrel, so that the reflection of invalid light is further blocked, and the imaging quality of the lens is effectively ensured; in order to guarantee the stability of cooperation between lens cone inner wall and each lens except having designed two spacer rings, still designed three piece clamping rings, its effect mainly lies in: after the lens is matched with the space ring, the space ring finally fixes and locks the lens, so that the stability and the reliability of the lens are ensured.

Drawings

FIG. 1 is a diagram of the optical path system of the present invention;

FIG. 2 is a schematic view of a lens structure according to the present invention;

FIG. 3 is a graph of MTF according to the present invention;

FIG. 4 is a graph of distortion variation of the present invention;

in the figure: 1. the lens comprises a front pressing ring 2, a first biconvex lens 3, a front space ring 4, a front lens cone 5, a first regular crescent lens 6, a biconcave lens 7, a second regular crescent lens 8, an extinction thread 9, a diaphragm 10, a third regular crescent lens 11, a middle partition ring 12, a fourth regular crescent lens 13, a middle pressing ring 14, a second biconvex lens 15, a negative crescent lens 16, a rear lens cone 17, a rear pressing ring 18, a threaded interface 19 and an image surface.

Detailed Description

In order to make the aforementioned features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below, but the present invention is not limited thereto.

Refer to fig. 1 to 4

A high-resolution industrial double-telecentric lens with the object distance of 0.5 times 110mm comprises a main lens barrel, wherein a front group lens A, a diaphragm 9 and a rear group lens B are sequentially arranged in the main lens barrel from front to back along the light incidence direction, and the front group lens is a first bonding group formed by tightly connecting a first biconvex lens 2, a first regular crescent lens 5, a biconcave lens 6 and a second regular crescent lens 7 in sequence; the rear group lens is a second adhesive combination formed by tightly connecting a third positive crescent lens 10, a fourth positive crescent lens 12, a second biconvex lens 14 and a negative crescent lens 15 in sequence.

In this embodiment, the air space between the first biconvex lens and the first regular crescent lens is 10 mm; the air space between the first positive crescent lens and the first gluing set is 0.64 mm.

In this embodiment, the air space between the front group of lenses and the rear group of lenses is 28.29 mm; the air space between the front group of lenses and the diaphragm is 28.15 mm; and the air interval between the diaphragm and the rear group of lenses is 0.14 mm.

In this embodiment, the air space between the third and fourth regular crescent lenses is 12.41 mm; and the air space between the fourth positive crescent lens and the second gluing set is 5.16 mm.

In this embodiment, the main lens barrel includes a front lens barrel 4 for mounting a first biconvex lens 2, a first regular crescent lens 5, a first cemented group, a third regular crescent lens 10, and a fourth regular crescent lens 12, a rear lens barrel 16 for mounting a second cemented group is connected to a rear end of the front lens barrel, and a screw interface 18, i.e., a C interface, is provided at a rear end of the rear lens barrel.

In the embodiment, the front lens barrel is provided with a front cavity and a rear cavity which are communicated, the front end of the front cavity is in threaded connection with a front pressing ring 1 for locking a first biconvex lens, a front space ring 3 is arranged between the first biconvex lens and a first regular crescent lens, the middle part of the front cavity is provided with a bearing surface for abutting against the periphery of the rear side of a second regular crescent lens, and the side wall of the rear part of the front cavity is provided with an extinction thread 8; the diaphragm is installed at the front end of the rear cavity and located on the front side of the third regular crescent lens, a middle partition ring 11 located between the third regular crescent lens and the fourth regular crescent lens is arranged in the rear cavity, and the rear end of the rear cavity is in threaded connection with a middle pressure ring 13 used for locking the fourth regular crescent lens.

In the embodiment, the front lens cone is integrally designed and is formed by a lathe in one-step processing mode, and the coaxiality of bearing surfaces of all lenses of the front lens cone is guaranteed.

In order to reduce the influence of stray light and ghost on the imaging quality of the lens, the front spacing ring and the middle spacing ring are designed into a step-shaped structure, and the positions matched with the lens and supported by the lens are designed into right-angle supporting, so that the air intervals among the first biconvex lens 2, the first regular crescent lens 5, the third regular crescent lens 10 and the fourth regular crescent lens 12 are effectively ensured, the stability matched with the lens is increased, and meanwhile, the entering and the reflection of ineffective light rays are effectively reduced.

In order to further eliminate stray light and ghost images, an extinction thread structure is designed on the inner wall of the front lens barrel, so that the reflection of invalid light is further blocked, and the imaging quality of the lens is effectively ensured; and the design of the front pressing ring and the middle pressing ring is matched with the front lens barrel, so that the final fixing and locking effects of the lens and the space ring are mainly achieved, and the stability and the reliability of the lens are ensured.

In this embodiment, a bearing surface for abutting against the periphery of the front side of the second biconvex lens is arranged in the rear lens barrel, and a rear pressing ring 17 for pressing the periphery of the rear side of the negative crescent lens is screwed at the rear part of the rear lens barrel.

In the embodiment, the rear lens cone is also designed in an integrated mode and is formed by a lathe in one-step machining mode, and the coaxiality of the front lens cone, the rear lens cone and the bearing surfaces of the lenses is guaranteed. In order to ensure the stability of the second gluing set, a rear pressing ring is designed to be matched with the rear lens cone, so that the lens is fixed, the movement of the lens is reduced, and the assembly stability of the lens is improved; and the rear lens cone and the front lens cone are in two-section type thread butt joint forming through threads, so that the coaxiality of the axes of the front and rear lenses is effectively realized. In addition, the tail part of the rear lens cone adopts a C interface design which is mainstream in the market at present, and can be matched with most industrial cameras in the market at first, so that the practicability is greatly improved.

In this embodiment, the parameters of each lens are shown in the following table:

。

the technical indexes that the lens can realize are as follows:

① size of image plane 2/3 ";

② magnification of 0.5X;

③ the distance between the work objects is 110 mm;

④ effective aperture F9.6;

⑤ optical distortion is less than or equal to 0.006%;

⑥ resolution is more than or equal to 500 ten thousand pixels;

⑦ depth of field is 3.02 mm;

⑧, the working temperature is-20 ℃ to 60 ℃;

⑨ lens size specification, 34mm phi x 106 mm.

It will be apparent to those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and it will be appreciated by those skilled in the art that various modifications can be made in the present invention without any inventive step in the design of a 0.5 × 110mm high resolution industrial double telecentric lens system without departing from the spirit and scope of the present invention.