Optical image rotation lens group and hard tube endoscope optical image rotation system

Abstract

The utility model discloses an optical image rotation lens group and a hard tube endoscope optical image rotation system, the optical image rotation lens group is composed of two separated optical glass lens groups, the two optical glass lens groups are symmetrically arranged, and a diaphragm is arranged between the two optical glass lens groups to form a 1: 1 double telecentric image rotation system; and each optical glass lens group consists of a group of double-bonding Hopkins rodlike lenses which are separately arranged and a group of double-bonding lenses. The double-gluing Hopkins rod-shaped lens is formed by gluing a Hopkins rod-shaped lens L1 and a double-convex optical glass lens L2, the double-gluing lens is formed by gluing a first meniscus optical glass lens L3 and a second meniscus optical glass lens L4, and the concave surface of the first meniscus optical glass lens L3 and the concave surface of the second meniscus optical glass lens L4 both face the position of the diaphragm. The aberration of the hard tube endoscope image rotation lens group is more effectively corrected, the angular resolution of an image rotation system is greatly improved under the condition that the aperture is not changed, and the durability and the imaging quality of the hard tube endoscope are improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of optical image transfer systems, and in particular relates to a high-resolution optical image transfer lens group and a hard tube endoscope optical image transfer system. Background Art

[0002] The optical system of a rigid endoscope consists of three parts: the imaging objective lens of the rigid endoscope, the image transfer lens system of the rigid endoscope, and the eyepiece of the rigid endoscope. The objective lens forms an inverted image of the target object, and the image transfer lens system uses an odd-numbered image transfer lens group to convert the inverted image formed by the objective lens into a 1:1 erect image at the object focal plane of the eyepiece, and make the working length of the endoscope meet the requirements. Finally, the observer observes the erect real image through the eyepiece.

[0003] As the times change, the field of rigid tube endoscopes pursues high imaging quality. In some laparoscopes and other large-caliber endoscope optical systems, the aperture is also large, which poses a greater challenge to the image transfer lens system in the optical system. When the aperture of the optical system is large, the traditional rigid tube endoscope optical image transfer lens group often has problems such as excessive aberration and insufficient lens aperture.

[0004] Figure 2 The figure shows an early rigid tube endoscope optical image-transmitting lens assembly, which is composed of two double-cemented thin lenses with the aperture located in the middle. The vertical axis aberration of the image-transmitting lens assembly with this structure is well corrected. However, due to the use of thin lenses, its light energy transmittance is low and the lenses are prone to tilt during assembly, so no company uses it now.

[0005] Figure 3 The optical image-transmitting lens assembly of the rigid tube endoscope shown includes two Hopkins rod lenses. This image-transmitting lens assembly has a simple structure, but cannot correct axial chromatic aberration and has poor imaging quality.

[0006] Figure 4 The optical image-transmitting lens assembly of the rigid tube endoscope shown is a symmetrical structure, in which one end of the Hopkins rod lens is glued to a negative lens with a negative focal length, and the thin lens uses optical glass with a high refractive index and high dispersion. Its advantage is its simple structure, and its disadvantage is that it can correct axial chromatic aberration but cannot correct field curvature.

[0007] Figure 5 The optical image transfer lens group of the rigid tube endoscope shown is a symmetrical structure, consisting of two symmetrical triplet lenses, with the aperture located between the two. The triplet lens is a Hopkins rod lens with an identical lens glued on each side of the rod lens. When the aperture is small, it can not only correct chromatic aberration, but also correct field curvature, and the image quality is high. When the aperture is large, the aberration is obvious and the image quality is greatly reduced. Summary of the invention

[0008] In order to solve the above-mentioned problems existing in the prior art, the utility model provides an optical image transfer lens group and an optical image transfer system of a rigid tube endoscope, which can more effectively correct the aberration of the image transfer lens group of the rigid tube endoscope, greatly improve the angular resolution of the image transfer system without changing the aperture, and improve the durability and imaging quality of the rigid tube endoscope.

[0009] The purpose of this utility model is achieved through the following technical solutions:

[0010] As a first aspect of the utility model, an optical image transfer lens group is provided, which is composed of two separate optical glass lens groups, the two optical glass lens groups are symmetrically arranged, and an aperture is provided between the two optical glass lens groups to form a 1:1 double telecentric image transfer system; each optical glass lens group is composed of a group of double-cemented Hopkins rod mirrors and a group of double-cemented lenses, and a group of double-cemented Hopkins rod mirrors and a group of double-cemented lenses are placed separately.

[0011] Furthermore, the double-cemented Hopkins rod mirror is composed of a Hopkins rod mirror L1 and a double convex optical glass lens L2 bonded together, one side of the Hopkins rod mirror L1 is convex, and the other side is concave and the concave surface is close to the aperture, and the concave surface of the Hopkins rod mirror is bonded to the double convex optical glass lens L2; ​​the double-cemented lens is composed of a first meniscus optical glass lens L3 and a second meniscus optical glass lens L4 bonded together, the concave surfaces of the first meniscus optical glass lens L3 and the second meniscus optical glass lens L4 both face the aperture position, and the first meniscus optical glass lens L3 and the second meniscus optical glass lens L4 have different structures.

[0012] Furthermore, the double-cemented Hopkins rod mirror and the double-cemented lens have the same diameter; the Hopkins rod mirror L1, the double convex optical glass lens L2, the first meniscus optical glass lens L3 and the second meniscus optical glass lens L4 are placed in sequence from the light incident direction; in the optical glass lens group, the curvature radius R1 of the first surface from the light incident direction ranges from 16mm to 40mm, the curvature radius R2 of the second surface ranges from 10mm to 20mm, and the curvature radius R3 of the third surface ranges from -16mm to -50mm m, the curvature radius R4 of the fourth surface ranges from 6mm to 9mm, the curvature radius R5 of the fifth surface ranges from 2.3mm to 4.6mm, and the curvature radius R6 of the sixth surface ranges from 4mm to 7mm; the thickness range of the Hopkins rod mirror L1 is 20mm to 40mm, the thickness range of the biconvex optical glass lens L2 is 1.2mm to 4mm, the thickness range of the first meniscus optical glass lens L3 is 1.2mm to 6mm, and the thickness range of the second meniscus optical glass lens L4 is 1.0mm to 4.0mm.

[0013] Furthermore, the materials of the Hopkins rod mirror L1 and the biconvex optical glass lens L2 are different, and the materials of the first meniscus optical glass lens L3 and the second meniscus optical glass lens are also different.

[0014] Furthermore, the Hopkins rod mirror L1, the biconvex optical glass lens L2, the first meniscus optical glass lens L3 and the second meniscus optical glass lens L4 are placed in sequence from the incident direction of light; the material refractive index range of the Hopkins rod mirror L1 is 1.50-1.64, the material refractive index range of the biconvex optical glass lens L2 is 1.72-2.00, the material refractive index range of the first meniscus optical glass lens L3 is 1.72-2.00, and the material refractive index range of the second meniscus optical glass lens L4 is 1.52-1.60.

[0015] Preferably, the material of the Hopkins rod mirror L1 is H-K9L, the material of the biconvex optical glass lens L2 is H-LAF50, the material of the first meniscus optical glass lens L3 is H-ZF73, and the material of the second meniscus optical glass lens L4 is N-PSK57.

[0016] Preferably, the material of the Hopkins rod mirror L1 is K9, the material of the biconvex optical glass lens L2 is H-ZLAF96, the material of the first meniscus optical glass lens L3 is H-ZF73, and the material of the second meniscus optical glass lens L4 is K9.

[0017] Preferably, the material of the Hopkins rod mirror L1 is BAM4, the material of the biconvex optical glass lens L2 is H-LAF50, the material of the first meniscus optical glass lens L3 is H-ZF73, and the material of the second meniscus optical glass lens L4 is BAM4.

[0018] Furthermore, the aperture range of the optical image transfer lens group is 2.8 mm to 6.0 mm.

[0019] As a second aspect of the utility model, an optical image relay system of a rigid tube endoscope is provided, which is composed of an odd number of optical image relay lens groups placed along the optical axis, and the optical image relay lens groups of the rigid tube endoscope are arranged in any order along the system optical axis.

[0020] The utility model has the following advantages:

[0021] The utility model provides an optical image transfer lens group and an optical image transfer system of a rigid tube endoscope, which can more effectively correct the aberration of the image transfer lens group of the rigid tube endoscope, greatly improve the angular resolution of the image transfer system without changing the aperture, and improve the durability and imaging quality of the rigid tube endoscope. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the structure of an optical image transfer lens assembly described in the utility model;

[0023] Figure 2 This is a schematic diagram of the structure of the optical image transfer lens group of an early rigid tube endoscope;

[0024] Figure 3 It is a schematic diagram of the structure of the optical image transfer lens group of the existing hard tube endoscope;

[0025] Figure 4 It is a schematic diagram of the structure of the optical image transfer lens group of the existing hard tube endoscope;

[0026] Figure 5 It is a schematic diagram of the structure of the optical image transfer lens group of the existing hard tube endoscope;

[0027] Figure 6 This is a schematic diagram of the structure of an optical image transfer lens assembly described in Example 1 of the utility model;

[0028] Figure 7 This is a schematic structural diagram of the optical image transfer system of the rigid tube endoscope described in Example 3 of the utility model;

[0029] Figure 8 This is a modulation transfer function (MTF) curve diagram of the optical image relay system of the rigid tube endoscope described in Example 3 of the utility model when the cutoff spatial frequency is 100lp / mm;

[0030] Fig. 9 This is a modulation transfer function (MTF) curve of the rigid tube endoscope optical image relay system described in Example 4 of the utility model when the cutoff spatial frequency is 100lp / mm. DETAILED DESCRIPTION

[0031] The technical solution of the utility model is further described below in conjunction with the accompanying drawings and embodiments:

[0032] like Figure 1 As shown, an optical image transfer lens group is composed of two separate optical glass lens groups, the two optical glass lens groups are symmetrically arranged, and an aperture is provided between the two optical glass lens groups to form a 1:1 double telecentric image transfer system; each optical glass lens group is composed of a group of double-cemented Hopkins rod mirrors and a group of double-cemented lenses, and a group of double-cemented Hopkins rod mirrors and a group of double-cemented lenses are placed separately.

[0033] Furthermore, the double-cemented Hopkins rod mirror and the double-cemented lens have the same diameter.

[0034] Furthermore, the double-cemented Hopkins rod mirror is composed of a Hopkins rod mirror L1 and a double convex optical glass lens L2 bonded together, one side of the Hopkins rod mirror L1 is convex, and the other side is concave and the concave surface is close to the aperture, and the concave surface of the Hopkins rod mirror is bonded to the double convex optical glass lens L2; ​​the double-cemented lens is composed of a first meniscus optical glass lens L3 and a second meniscus optical glass lens L4 bonded together, the concave surfaces of the first meniscus optical glass lens L3 and the second meniscus optical glass lens L4 both face the aperture position, and the first meniscus optical glass lens L3 and the second meniscus optical glass lens L4 have different structures.

[0035] Furthermore, the Hopkins rod mirror L1, the biconvex optical glass lens L2, the first meniscus optical glass lens L3 and the second meniscus optical glass lens L4 are placed in sequence from the light incident direction; in the optical glass lens group, the curvature radius R1 of the first surface from the light incident direction ranges from 16mm to 40mm, the curvature radius R2 of the second surface ranges from 10mm to 20mm, the curvature radius R3 of the third surface ranges from -16mm to -50mm, the curvature radius R4 of the fourth surface ranges from 6mm to 9mm, the curvature radius R5 of the fifth surface ranges from 2.3mm to 4.6mm, and the curvature radius R6 of the sixth surface ranges from 4mm to 7mm.

[0036] Furthermore, the thickness of the Hopkins rod mirror L1 ranges from 20 mm to 40 mm, the thickness of the biconvex optical glass lens L2 ranges from 1.2 mm to 4 mm, the thickness of the first meniscus optical glass lens L3 ranges from 1.2 mm to 6 mm, and the thickness of the second meniscus optical glass lens L4 ranges from 1.0 mm to 4.0 mm.

[0037] Furthermore, the materials of the Hopkins rod mirror L1 and the biconvex optical glass lens L2 are different, and the materials of the first meniscus optical glass lens L3 and the second meniscus optical glass lens are also different.

[0038] Furthermore, the Hopkins rod mirror L1, the biconvex optical glass lens L2, the first meniscus optical glass lens L3 and the second meniscus optical glass lens L4 are placed in sequence from the incident direction of light; the material refractive index range of the Hopkins rod mirror L1 is 1.50-1.64, the material refractive index range of the biconvex optical glass lens L2 is 1.72-2.00, the material refractive index range of the first meniscus optical glass lens L3 is 1.72-2.00, and the material refractive index range of the second meniscus optical glass lens L4 is 1.52-1.60.

[0039] Preferably, the material of the Hopkins rod mirror L1 is H-K9L, the material of the biconvex optical glass lens L2 is H-LAF50, the material of the first meniscus optical glass lens L3 is H-ZF73, and the material of the second meniscus optical glass lens L4 is N-PSK57.

[0040] Preferably, the material of the Hopkins rod mirror L1 is K9, the material of the biconvex optical glass lens L2 is H-ZLAF96, the material of the first meniscus optical glass lens L3 is H-ZF73, and the material of the second meniscus optical glass lens L4 is K9.

[0041] Preferably, the material of the Hopkins rod mirror L1 is BAM4, the material of the biconvex optical glass lens L2 is H-LAF50, the material of the first meniscus optical glass lens L3 is H-ZF73, and the material of the second meniscus optical glass lens L4 is BAM4.

[0042] Furthermore, the focal length of the 1:1 dual telecentric system satisfies the range of 500 mm to 1.0×10 5 mm.

[0043] Furthermore, the aperture range of the optical image transfer lens group is 2.8 mm to 6.0 mm.

[0044] An optical image transfer system of a rigid tube endoscope is composed of an odd number of optical image transfer lens groups placed along an optical axis, and the optical image transfer lens groups of the rigid tube endoscope are arranged in any order along the system optical axis.

[0045] Example 1

[0046] like Figure 6 As shown, an optical image transfer lens group is composed of two separate optical glass lens groups, the two optical glass lens groups are symmetrically arranged, and an aperture is provided between the two optical glass lens groups to form a 1:1 double telecentric image transfer system; each optical glass lens group is composed of a double-cemented lens and a double-cemented Hopkins rod mirror, and the interval between the double-cemented lens and the double-cemented Hopkins rod mirror is 0.3 mm.

[0047] The optical image transfer lens assembly described in this embodiment has a focal length greater than 500 mm, a working length of 98 mm, and an aperture of 6.0 mm, and can be used in laparoscopes.

[0048] Among them, the material of the Hopkins rod mirror L1 is K9, the material of the double convex optical glass lens L2 is H-ZLAF96, the material of the first meniscus optical glass lens L3 is H-ZF73, and the material of the second meniscus optical glass lens L4 is K9.

[0049] Example 2

[0050] An optical image transfer lens group is composed of two separate optical glass lens groups, which are symmetrically arranged and provided with an aperture in the middle of the two optical glass lens groups, so as to form a 1:1 double telecentric image transfer system; each optical glass lens group is composed of a double-cemented lens and a double-cemented Hopkins rod mirror, and the interval between the double-cemented lens and the double-cemented Hopkins rod mirror is 0.7 mm.

[0051] The optical image transfer lens assembly described in this embodiment has a focal length greater than 350 mm, a working length of 98 mm, and an aperture of 6.0 mm, and can be used in laparoscopes.

[0052] Among them, the material of the Hopkins rod mirror L1 is BAM4, the material of the double convex optical glass lens L2 is H-LAF50, the material of the first meniscus optical glass lens L3 is H-ZF88, and the material of the second meniscus optical glass lens L4 is BAM4.

[0053] Example 3

[0054] like Figure 7 As shown, an optical image relay system of a rigid tube endoscope comprises three groups of optical image relay lens groups described in Example 1 arranged along the optical axis. The optical image relay lens groups can be arranged in any front-to-back order along the optical axis of the system.

[0055] like Figure 8 The modulation transfer function (MTF) curve of the optical image relay system of this embodiment is given when the cutoff spatial frequency is 100lp / mm. Figure 8 It can be concluded that the MTF value in the full field of view is higher than 0.5, which has a very high resolution.

[0056] Example 4

[0057] An optical image transfer system for a rigid tube endoscope comprises three groups of optical image transfer lens groups as described in Example 2 arranged along an optical axis. The optical image transfer lens groups can be arranged in any front-to-back order along the optical axis of the system.

[0058] like Fig. 9 The modulation transfer function (MTF) curve of the optical image relay system of this embodiment is given when the cutoff spatial frequency is 110lp / mm. Fig. 9 It can be concluded that the MTF value in the full field of view is close to 0.5, which has a very high resolution.

[0059] The above describes the basic principles and features of the utility model, and the embodiments are not intended to limit the utility model. Without departing from the spirit and scope of the utility model, any changes and improvements made shall fall within the protection scope of the utility model.

Claims

1. An optical image relay lens assembly, characterized in that: It consists of two separate optical glass lens groups, which are symmetrically arranged and have an aperture in the middle, forming a 1:1 double telecentric image transfer system; each optical glass lens group consists of a group of double-cemented Hopkins rod mirrors and a group of double-cemented lenses, and a group of double-cemented Hopkins rod mirrors and a group of double-cemented lenses are placed separately.

2. The optical image relay lens assembly according to claim 1, characterized in that: The double-cemented Hopkins rod mirror is composed of a Hopkins rod mirror L1 and a double convex optical glass lens L2 bonded together. One side of the Hopkins rod mirror L1 is convex, and the other side is concave and the concave surface is close to the aperture. The concave surface of the Hopkins rod mirror is bonded to the double convex optical glass lens L2. The double-cemented lens is composed of a first meniscus optical glass lens L3 and a second meniscus optical glass lens L4 bonded together. The concave surfaces of the first meniscus optical glass lens L3 and the second meniscus optical glass lens L4 both face the aperture position, and the first meniscus optical glass lens L3 and the second meniscus optical glass lens L4 have different structures.

3. The optical image relay lens assembly according to claim 2, characterized in that: The double-cemented Hopkins rod mirror has the same diameter as the double-cemented lens; the Hopkins rod mirror L1, the double-convex optical glass lens L2, the first meniscus optical glass lens L3 and the second meniscus optical glass lens L4 are placed in sequence from the light incident direction; in the optical glass lens group, the curvature radius R1 of the first surface from the light incident direction ranges from 16mm to 40mm, the curvature radius R2 of the second surface ranges from 10mm to 20mm, the curvature radius R3 of the third surface ranges from -16mm to -50mm, and the curvature radius R4 of the second surface ranges from -16mm to -50mm. The curvature radius R4 of the four surfaces ranges from 6mm to 9mm, the curvature radius R5 of the fifth surface ranges from 2.3mm to 4.6mm, and the curvature radius R6 of the sixth surface ranges from 4mm to 7mm; the thickness of the Hopkins rod mirror L1 ranges from 20mm to 40mm, the thickness of the biconvex optical glass lens L2 ranges from 1.2mm to 4mm, the thickness of the first meniscus optical glass lens L3 ranges from 1.2mm to 6mm, and the thickness of the second meniscus optical glass lens L4 ranges from 1.0mm to 4.0mm.

4. The optical image relay lens assembly according to claim 2, characterized in that: The Hopkins rod mirror L1 and the biconvex optical glass lens L2 are made of different materials, and the first meniscus optical glass lens L3 and the second meniscus optical glass lens are also made of different materials.

5. The optical image relay lens assembly according to claim 2, characterized in that: The Hopkins rod mirror L1, the biconvex optical glass lens L2, the first meniscus optical glass lens L3 and the second meniscus optical glass lens L4 are placed in sequence from the incident direction of light; the material refractive index range of the Hopkins rod mirror L1 is 1.50-1.64, the material refractive index range of the biconvex optical glass lens L2 is 1.72-2.00, the material refractive index range of the first meniscus optical glass lens L3 is 1.72-2.00, and the material refractive index range of the second meniscus optical glass lens L4 is 1.52-1.

60.

6. The optical image relay lens assembly according to claim 2, characterized in that: The material of the Hopkins rod mirror L1 is H-K9L, the material of the biconvex optical glass lens L2 is H-LAF50, the material of the first meniscus optical glass lens L3 is H-ZF73, and the material of the second meniscus optical glass lens L4 is N-PSK57.

7. The optical image relay lens assembly according to claim 2, characterized in that: The material of the Hopkins rod mirror L1 is K9, the material of the double convex optical glass lens L2 is H-ZLAF96, the material of the first meniscus optical glass lens L3 is H-ZF73, and the material of the second meniscus optical glass lens L4 is K9.

8. The optical image relay lens assembly according to claim 2, characterized in that: The material of the Hopkins rod mirror L1 is BAM4, the material of the biconvex optical glass lens L2 is H-LAF50, the material of the first meniscus optical glass lens L3 is H-ZF73, and the material of the second meniscus optical glass lens L4 is BAM4.

9. The optical image relay lens assembly according to claim 2, characterized in that: The aperture range of the optical image transfer lens group is 2.8 mm to 6.0 mm.

10. An optical image relay system for a rigid tube endoscope, characterized in that: The optical image-transmitting lens group is composed of an odd number of optical image-transmitting lens groups as claimed in any one of claims 1 to 9 placed along the optical axis, and the optical image-transmitting lens groups of the rigid tube endoscope are arranged in any order along the system optical axis.

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