阅读说明：本技术 一种双远心光学系统及光学设备 (Double-telecentric optical system and optical equipment ) 是由 刘焕宝 马艺函 杨峥 于 2018-06-05 设计创作，主要内容包括：本发明提供了一种双远心光学系统及光学设备,包括共轴放置的第一透镜组、第二透镜组、第三透镜组以及第四透镜组,所述第一透镜组包括第一透镜、第二透镜,所述第二透镜组包括第三透镜、第四透镜、第五透镜,所述第三透镜组包括第六透镜、第七透镜、第八透镜,所述第四透镜组包括第九透镜,双远心光学系统的相对孔径为1/6,解决了在照明条件不佳的情况下,也可成像清晰的技术问题,还具有高分辨率、高远心度及低畸变的技术优点。(The invention provides a double telecentric optical system and optical equipment, which comprise a first lens group, a second lens group, a third lens group and a fourth lens group which are coaxially arranged, wherein the first lens group comprises a first lens and a second lens, the second lens group comprises a third lens, a fourth lens and a fifth lens, the third lens group comprises a sixth lens, a seventh lens and an eighth lens, the fourth lens group comprises a ninth lens, and the relative aperture of the double telecentric optical system is 1/6, so that the technical problem of clear imaging under the poor illumination condition is solved, and the double telecentric optical system and the optical equipment also have the technical advantages of high resolution, high telecentricity and low distortion.)

1. a double telecentric optical system is characterized by comprising a first lens group, a second lens group, a third lens group and a fourth lens group which are coaxially arranged, wherein the first lens group comprises a first lens and a second lens, the second lens group comprises a third lens, a fourth lens and a fifth lens, the third lens group comprises a sixth lens, a seventh lens and an eighth lens, the fourth lens group comprises a ninth lens, and the relative aperture of the double telecentric optical system is 1/6.

2. double telecentric optical system according to claim 1, characterized in that the object distance of the first lens group is 92 mm.

3. Double telecentric optical system according to claim 1 or 2, characterized in that the first lens has a radius of curvature of the object side of 73.21 and a radius of curvature of the mirror side of-345.10;

the curvature radius of the object side surface of the second lens is 32.21, and the curvature radius of the mirror side surface of the second lens is 50.70;

The curvature radius of the object side surface of the third lens is-223.6, and the curvature radius of the mirror side surface of the third lens is 14.28;

The curvature radius of the object side surface of the fourth lens is-28.47, and the curvature radius of the mirror side surface of the fourth lens is 73.07;

The curvature radius of the object side surface of the fifth lens is 73.7, and the curvature radius of the mirror side surface of the fifth lens is-23.21;

the curvature radius of the object side surface of the sixth lens is-21.83, and the curvature radius of the mirror side surface of the sixth lens is-4.48;

The curvature radius of the object side surface of the seventh lens is-4.48, and the curvature radius of the mirror side surface of the seventh lens is 66.20;

The curvature radius of the object side surface of the eighth lens is-80.55, and the curvature radius of the mirror side surface of the eighth lens is 12.71;

the ninth lens has an object side curvature radius of 40.82 and a mirror side curvature radius of-70.99, wherein the signs of the curvature radii are defined in geometric optics.

4. the double telecentric optical system of claim 3, wherein the first lens has a thickness of 13.9mm, the second lens has a thickness of 11.9mm, the third lens has a thickness of 3.7mm, the fourth lens has a thickness of 3.3mm, the second lensless has a thickness of 8.0mm, the sixth lens has a thickness of 4.6mm, the seventh lens has a thickness of 2.4mm, the eighth lens has a thickness of 5.1mm, and the second lens has a thickness of 4.9 mm.

5. The double telecentric optical system of claim 3, wherein the air separation between the first lens and the second lens is 0.18mm, the air separation between the second lens and the third lens is 14.65mm, the air separation between the third lens and the fourth lens is 5.12mm, the air separation between the fourth lens and the fifth lens is 0mm, the air separation between the fifth lens and the sixth lens is 19.28mm, the air separation between the sixth lens and the seventh lens is 0mm, the air separation between the seventh lens and the eighth lens is 1.71mm, the air separation between the eighth lens and the ninth lens is 12.45mm, and the air separation between the ninth lens and the CCD target surface is 20.99 mm.

6. A double telecentric optical system according to claim 3 wherein the fourth lens and the fifth lens are a double cemented lens group and the sixth lens and the seventh lens are a double cemented lens group.

7. A double telecentric optical system according to claim 1 wherein the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, the eighth lens and the ninth lens are all spherical lenses.

8. double telecentric optical system according to claim 5, characterized in that the CCD target surface has dimensions of 2/3 inches.

9. An optical apparatus having a double telecentric optical system according to any one of claims 1 to 8.

10. The optical device of claim 9, wherein the optical device is a camera, video recorder, telescope, or hyper-telephoto lens.

Technical Field

The invention relates to the field of optical equipment, in particular to a double telecentric optical system and optical equipment.

background

Industrial lenses are important imaging elements in machine vision systems, and in order to fully function, industrial lenses must meet the requirements. In the beginning of the 21 st century, with the wide application of machine vision systems in the field of precision detection, common industrial lenses are difficult to meet the detection requirements, and telecentric lenses are produced in order to make up for the defects of common lenses and adapt to the requirements of precision detection. Telecentric lenses are based on their unique optical properties: high resolution, ultra-wide depth of field, ultra-low distortion, unique parallel light design and the like, and brings qualitative leap for machine vision precision detection.

The telecentric lens is mainly designed for correcting the parallax of the traditional industrial lens, and can ensure that the magnification of the obtained image is not changed within a certain object distance range, which is very important to the condition that the measured object is not on the same object plane. Telecentric lenses have been favored for machine vision applications where lens distortion is highly demanding due to their unique parallel optical path design.

when the entrance pupil is located at a distance from the optical system close to infinity, the optical system is telecentric at the object space; when the exit pupil is positioned at a distance close to infinity from the optical system, the optical system is telecentric at the image space; when the entrance pupil and the exit pupil are respectively located at infinity of the optical system, the optical system is object image bilateral telecentric, which is called as a double telecentric optical lens for short, and the double telecentric industrial lens on the market has a small relative aperture (mostly 1/10 or less), and can form a clear image under a good illumination condition, which greatly limits the use scene of the double telecentric lens.

Disclosure of Invention

The embodiment of the invention provides a double telecentric optical system and optical equipment, which solve the technical problem of clear imaging under the condition of poor illumination condition.

In a first aspect, the present invention provides a double telecentric optical system, comprising a first lens group, a second lens group, a third lens group and a fourth lens group which are coaxially arranged, wherein the first lens group comprises a first lens and a second lens, the second lens group comprises a third lens, a fourth lens and a fifth lens, the third lens group comprises a sixth lens, a seventh lens and an eighth lens, the fourth lens group comprises a ninth lens, and the relative aperture of the double telecentric optical system is 1/6.

Alternatively, the object distance of the first lens group is 92 mm.

Optionally, the first lens has an object side radius of curvature of 73.21 and a mirror side radius of curvature of-345.10;

The curvature radius of the object side surface of the second lens is 32.21, and the curvature radius of the mirror side surface of the second lens is 50.70;

the curvature radius of the object side surface of the third lens is-223.6, and the curvature radius of the mirror side surface of the third lens is 14.28;

The curvature radius of the object side surface of the fourth lens is-28.47, and the curvature radius of the mirror side surface of the fourth lens is 73.07;

The curvature radius of the object side surface of the fifth lens is 73.7, and the curvature radius of the mirror side surface of the fifth lens is-23.21;

The curvature radius of the object side surface of the sixth lens is-21.83, and the curvature radius of the mirror side surface of the sixth lens is-4.48;

The curvature radius of the object side surface of the seventh lens is-4.48, and the curvature radius of the mirror side surface of the seventh lens is 66.20;

the curvature radius of the object side surface of the eighth lens is-80.55, and the curvature radius of the mirror side surface of the eighth lens is 12.71;

The ninth lens has an object side curvature radius of 40.82 and a mirror side curvature radius of-70.99, wherein the signs of the curvature radii are defined in geometric optics.

as an alternative, the thickness of the first lens is 13.9mm, the thickness of the second lens is 11.9mm, the thickness of the third lens is 3.7mm, the thickness of the fourth lens is 3.3mm, the thickness of the second lens is 8.0mm, the thickness of the sixth lens is 4.6mm, the thickness of the seventh lens is 2.4mm, the thickness of the eighth lens is 5.1mm, and the thickness of the second lens is 4.9 mm.

as an alternative, the air space between the first lens and the second lens is 0.18mm, the air space between the second lens and the third lens is 14.65mm, the air space between the third lens and the fourth lens is 5.12mm, the air space between the fourth lens and the fifth lens is 0mm, the air space between the fifth lens and the sixth lens is 19.28mm, the air space between the sixth lens and the seventh lens is 0mm, the air space between the seventh lens and the eighth lens is 1.71mm, the air space between the eighth lens and the ninth lens is 12.45mm, and the air space between the ninth lens and the CCD target surface is 20.99 mm.

As an alternative, the fourth lens and the fifth lens are a double cemented lens group, and the sixth lens and the seventh lens are a double cemented lens group.

as an alternative, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, the eighth lens and the ninth lens are all spherical lenses.

alternatively, the CCD target surface is 2/3 inches in size.

in a second aspect, the present invention provides an optical apparatus characterized by having the double telecentric optical system described above.

Alternatively, the optical device is a camera, video recorder, telescope or super-telephoto lens.

According to the technical scheme, the embodiment of the invention has the following advantages:

The invention provides a double telecentric optical system and optical equipment, which comprise a first lens group, a second lens group, a third lens group and a fourth lens group which are coaxially arranged, wherein the first lens group comprises a first lens and a second lens, the second lens group comprises a third lens, a fourth lens and a fifth lens, the third lens group comprises a sixth lens, a seventh lens and an eighth lens, the fourth lens group comprises a ninth lens, and the relative aperture of the double telecentric optical system is 1/6, so that the technical problem of clear imaging under the poor illumination condition is solved, and the double telecentric optical system and the optical equipment also have the technical advantages of high resolution, high telecentricity and low distortion.

Drawings

FIG. 1 is a schematic diagram of the structure of one embodiment of a double telecentric optical system of the present invention;

FIG. 2 is a schematic optical path diagram of one embodiment of a double telecentric optical system of the present invention;

FIG. 3 is an image plane plot of one embodiment of a double telecentric optical system of the present invention;

FIG. 4 is an image plane transfer function diagram of one embodiment of a double telecentric optical system of the present invention;

FIG. 5 is an image plane distortion diagram of an embodiment of a double telecentric optical system of the present invention.

Detailed Description

In order to make the technical solutions of the present invention better understood, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.