CN221616922U - Ji Bianjiao optical adapter and medical endoscope - Google Patents

Abstract

The application relates to an optical adapter with an even zoom function and a medical endoscope. Ji Bianjiao the optical adapter includes: a first lens having negative optical power, the image-side surface being concave; the variable power group with positive focal power comprises a second lens, a third lens and a fourth lens with positive focal power, wherein the second lens and the third lens are glued to form a first glued lens group with positive focal power; a compensation group with negative focal power, comprising a fifth lens, a sixth lens with negative focal power, a seventh lens and an eighth lens, wherein the seventh lens and the eighth lens are glued to form a second glued lens group with positive focal power; a ninth lens having positive optical power; the variable magnification group and the compensation group are movable along an optical axis. The Ji Bianjiao optical adapter can obtain the effects of large aperture, miniaturization, high resolution, good imaging quality and the like.

Description

Ji Bianjiao optical adapter and medical endoscope

Technical Field

The application relates to the technical field of endoscopes, in particular to a zoom optical adapter and a medical endoscope.

Background

The medical endoscope is medical equipment which can enter a human body to observe, diagnose or treat, and generally comprises a camera and an endoscope mirror, wherein the camera is in optical path communication with the endoscope mirror through an optical adapter, and the optical adapter is used for adjusting light collected by the endoscope mirror and then projecting the light to the camera. The optical adapters are functionally divided into fixed focus adapters (i.e., zoom optical adapters) and variable focus adapters (i.e., zoom optical adapters).

With the rapid development of medical endoscopes, the performance requirements of the industry on the medical endoscopes are also higher and higher. Wherein, the imaging quality of the medical endoscope directly influences the efficiency and the accuracy of diagnosis or treatment. However, current zoom optical adapters have poor imaging quality, which can easily affect the efficiency and accuracy of diagnosis and treatment.

Disclosure of Invention

Accordingly, it is necessary to provide a zoom optical adapter and a medical endoscope for solving the problem that the conventional zoom optical adapter is poor in imaging quality.

An anamorphic optical adapter comprising, in order from an object side to an image side along an optical axis:

a first lens having negative optical power, an image side surface of the first lens being a concave surface;

The variable magnification group with positive focal power sequentially comprises a second lens, a third lens and a fourth lens with positive focal power from an object side to an image side along an optical axis, and the second lens and the third lens are glued to form a first glued lens group with positive focal power;

The optical lens comprises a compensation group with negative focal power, wherein the compensation group sequentially comprises a fifth lens, a sixth lens with negative focal power, a seventh lens and an eighth lens from an object side to an image side along an optical axis, and the seventh lens and the eighth lens are glued to form a second glued lens group with positive focal power;

A ninth lens having positive optical power;

The variable magnification group and the compensation group are movable along an optical axis between the first lens and the ninth lens to achieve an optical zoom function.

The Ji Bianjiao optical adapter is provided with the zoom group and the compensation group which move along the optical axis, and the compensation group can also compensate the position change of the imaging surface on the optical axis while realizing the optical zooming function, so that the position of the imaging surface on the optical axis is kept relatively stable, the realization of the zoom-in function is facilitated, and the zoom-in optical adapter can maintain good imaging quality in the zooming process. Meanwhile, the first lens and the ninth lens are arranged, the first lens with negative focal power can well collect light and expand the aperture, the ninth lens with positive focal power can effectively converge the light to the imaging surface, the adaptability of the zoom-in optical adapter and the image side optical structure is improved, and the effects of large aperture, high resolution and the like are achieved.

The negative focal power of the first lens, the positive focal power of the zoom group, the negative focal power of the compensation group and the positive focal power of the ninth lens are matched, so that light can smoothly transition in the zoom optical adapter, generation of aberration is restrained, aberration sensitivity is reduced, and imaging quality is improved. The negative focal power of the first lens is matched with the concave design of the image side surface of the first lens, so that light rays are collected and are dispersed towards the image side, the light inlet quantity and the aperture of the zoom optical adapter are improved, and the imaging brightness and the imaging quality are improved. The positive focal power of the first gluing lens group and the positive focal power of the fourth lens in the zoom lens group are matched with each other, light can be gently converged and transited towards the image side, the total length of the zoom optical adapter is shortened, meanwhile, the light transition is more gentle, aberration such as distortion of an edge view field is effectively restrained, the light is filled in a pupil by matching with the focal power of the first lens and the focal power of the fifth lens and the surface type design, the large aperture design is realized, the zoom optical adapter can meet the requirement of relative illumination, the edge view field illumination is improved, and the imaging quality of the zoom optical adapter in a weak light environment is improved. The negative focal power of the sixth lens and the positive focal power of the second cemented lens group are matched with the focal power design of the fifth lens and the variable-magnification lens group, so that light rays can be smoothly transited, aberration is corrected, aberration sensitivity of the anamorphic optical adapter is reduced, imaging quality is improved, light rays can be reasonably dispersed to an image side, and aperture of the anamorphic optical adapter is enlarged. The ninth lens has positive focal power, light rays reasonably transiting each lens on the object side can be converged towards the imaging surface, and the adaptability of the light rays and the image side optical structure is improved. Therefore, the Ji Bianjiao optical adapter can obtain the effects of large aperture, miniaturization, high resolution, good imaging quality and the like, and is beneficial to improving the accuracy of diagnosis and treatment.

In one embodiment, the Ji Bianjiao optical adapter satisfies the following conditional expression:

0.2≤（D1/TTL）≤0.4；

0.1≤（D2/TTL）≤0.2；

Wherein D1 is the stroke of the variable magnification group on the optical axis, D2 is the stroke of the compensation group on the optical axis, and TTL is the total length of the Ji Bianjiao optical adapter.

In one embodiment, the Ji Bianjiao optical adapter satisfies the following conditional expression:

22≤|F1/CT1|≤28；

wherein F1 is the effective focal length of the first lens, and CT1 is the thickness of the first lens on the optical axis.

In one embodiment, the Ji Bianjiao optical adapter satisfies the following conditional expression:

5≤F23/CT23≤7；

Wherein F23 is the effective focal length of the first cemented lens group, and CT23 is the thickness of the first cemented lens group on the optical axis.

In one embodiment, the Ji Bianjiao optical adapter satisfies the following conditional expression:

0.8≤F4/F23≤1.2；

Wherein F4 is an effective focal length of the fourth lens, and F23 is an effective focal length of the first cemented lens group.

In one embodiment, the Ji Bianjiao optical adapter satisfies the following conditional expression:

F5/CT5 is more than or equal to 10 and less than or equal to 11; and/or the number of the groups of groups,

10.5≤F9/CT9≤11.5；

Wherein F5 is an effective focal length of the fifth lens, CT5 is a thickness of the fifth lens on an optical axis, F9 is an effective focal length of the ninth lens, and CT9 is a thickness of the ninth lens on the optical axis.

In one embodiment, the Ji Bianjiao optical adapter satisfies the following conditional expression:

F6 is more than or equal to 0.3% F5 is less than or equal to 0.4; and/or the number of the groups of groups,

0.5≤|F6/F78|≤0.6；

Wherein F6 is an effective focal length of the sixth lens, F5 is an effective focal length of the fifth lens, and F78 is an effective focal length of the second cemented lens group.

In one embodiment, the first lens can move along the optical axis at the object side of the variable magnification group so as to realize an optical focusing function;

And/or, the Ji Bianjiao optical adapter further comprises a diaphragm, the diaphragm is arranged between the fifth lens and the sixth lens, and the diaphragm can synchronously move along an optical axis along with the compensation group.

In one embodiment, the object side surface of the first lens is a concave surface; and/or the number of the groups of groups,

The second lens has positive focal power, the object side surface of the second lens is a convex surface, the image side surface of the second lens is a concave surface, the third lens has positive focal power, and the object side surface and the image side surface of the third lens are both convex surfaces; and/or the number of the groups of groups,

The object side surface of the fourth lens is a convex surface, and the image side surface is a plane; and/or the number of the groups of groups,

The fifth lens has negative focal power, and both the object side surface and the image side surface of the fifth lens are concave surfaces; and/or the number of the groups of groups,

The object side surface and the image side surface of the sixth lens are concave surfaces; and/or the number of the groups of groups,

The seventh lens is provided with negative focal power, the object side surface of the seventh lens is a plane, the image side surface of the seventh lens is a concave surface, the eighth lens is provided with positive focal power, and the object side surface and the image side surface of the eighth lens are both convex surfaces; and/or the number of the groups of groups,

The object side surface and the image side surface of the ninth lens are both convex surfaces.

A medical endoscope comprising a zoom optical adapter as described in any of the embodiments above.

Drawings

Fig. 1 is a schematic diagram of a configuration of an anamorphic optical adapter in a wide-angle state in some embodiments.

Fig. 2 is a schematic diagram of a configuration of an anamorphic optical adapter in a tele state in some embodiments.

Fig. 3 is a graph of transfer functions of a zoom optical adapter in a wide-angle state in some embodiments.

Fig. 4 is a defocus plot of the zoom optical adapter in the wide-angle state in some embodiments.

FIG. 5 is a graph of field curvature and a graph of distortion for a zoom optical adapter in a wide-angle state in some embodiments.

FIG. 6 is a graph of transfer functions of a zoom optical adapter in mid-focus state in some embodiments.

FIG. 7 is a defocus plot of the zoom optical adapter in a mid-focus state in some embodiments.

FIG. 8 is a graph of field curvature and a graph of distortion of a zoom optical adapter in mid-focus state in some embodiments.

FIG. 9 is a graph of transfer functions of a zoom optical adapter in a tele state in some embodiments.

FIG. 10 is a defocus plot of the zoom optical adapter in a tele state in some embodiments.

FIG. 11 is a graph of field curvature and distortion curves for a zoom optical adapter in a tele state in some embodiments.

10. Ji Bianjiao an optical adapter; l1, a first lens; g1, a zoom group; l23, a first gluing lens group; l2, a second lens; l3, a third lens; l4, a fourth lens; g2, compensation group; l5, a fifth lens; l6, sixth lens; l78, a second gluing lens group; l7, seventh lens; l8, eighth lens; l9, ninth lens; 11. an optical axis; 12. an imaging surface; 13. a first protection element; 14. a second protection element; 15. a diaphragm.

Detailed Description

In order that the above objects, features and advantages of the application will be readily understood, a more particular description of the application will be rendered by reference to the appended drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. The present application may be embodied in many other forms than described herein and similarly modified by those skilled in the art without departing from the spirit of the application, whereby the application is not limited to the specific embodiments disclosed below.

In the description of the present application, it should be understood that, if any, these terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., are used herein with respect to the orientation or positional relationship shown in the drawings, these terms refer to the orientation or positional relationship for convenience of description and simplicity of description only, and do not indicate or imply that the apparatus or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the application.

Furthermore, the terms "first," "second," and the like, if any, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In the description of the present application, the terms "plurality" and "a plurality" if any, mean at least two, such as two, three, etc., unless specifically defined otherwise.

In the present application, unless explicitly stated and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly. For example, the two parts can be fixedly connected, detachably connected or integrated; can be mechanically or electrically connected; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art according to the specific circumstances.

In the present application, unless expressly stated or limited otherwise, the meaning of a first feature being "on" or "off" a second feature, and the like, is that the first and second features are either in direct contact or in indirect contact through an intervening medium. Moreover, a first feature being "above," "over" and "on" a second feature may be a first feature being directly above or obliquely above the second feature, or simply indicating that the first feature is level higher than the second feature. The first feature being "under", "below" and "beneath" the second feature may be the first feature being directly under or obliquely below the second feature, or simply indicating that the first feature is less level than the second feature.

It will be understood that if an element is referred to as being "fixed" or "disposed" on another element, it can be directly on the other element or intervening elements may also be present. If an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like as used herein, if any, are for descriptive purposes only and do not represent a unique embodiment.

Referring to fig. 1, the present application provides a zoom optical adapter 10, which can be applied to medical instruments, such as a hard tube medical endoscope, wherein the medical endoscope may include a camera and an endoscope mirror, and the zoom optical adapter 10 may be disposed between the endoscope mirror and the camera to adjust light collected by the endoscope mirror and then project the light onto the camera, so as to realize optical path communication between the camera and the endoscope mirror. In some embodiments, ji Bianjiao the optical adapter 10 includes, in order from the object side to the image side along the optical axis 11, a front fixed group, a variable magnification group G1, a compensation group G2, and a rear fixed group. The front fixed group includes a first lens L1, the variable magnification group G1 includes a second lens L2, a third lens L3 and a fourth lens L4 sequentially from an object side to an image side along the optical axis 11, the second lens L2 and the third lens L3 are glued together to form a first glued lens group L23 with positive optical power, and the fourth lens L4 has positive optical power. The compensation group G2 sequentially includes a fifth lens L5, a sixth lens L6, a seventh lens L7, and an eighth lens L8 along the optical axis 11 from the object side to the image side, and the seventh lens L7 and the eighth lens L8 are cemented together to form a second cemented lens group L78. The rear fixed group includes a ninth lens L9.

In some embodiments, the variable magnification group G1 and the compensation group G2 are movable along the optical axis 11 between the first lens L1 and the rear fixed group to achieve the optical zoom function of the ziplowing optical adapter 10. In some embodiments, ji Bianjiao the optical adapter 10 further includes an imaging plane 12 disposed on the image side of the ninth lens L9, and the incident light can strike the imaging plane 12 after being adjusted by each lens in the zoom optical adapter 10.

In some embodiments, the Ji Bianjiao optical adapter 10 may further include a first protection element 13 disposed on the object side of the first lens L1 and a second protection element 14 disposed on the image side of the ninth lens L9. The first protection element 13 and the second protection element 14 may each be a glass plate, and the first protection element 13 and the second protection element 14 are used to protect lenses in the zoom optical adapter 10 and a camera or other optical structure provided on the image side.

Further, in some embodiments, the first lens L1 has negative optical power, and the image side surface of the first lens L1 is concave. The fourth lens L4 has positive optical power, and the first cemented lens group L23 has positive optical power. The fifth lens L5 has an optical power, the sixth lens L6 has a negative optical power, and the second cemented lens group L78 has a positive optical power. The ninth lens L9 has positive optical power.

In the Ji Bianjiao optical adapter 10, the zoom group G1 and the compensation group G2 are set to move along the optical axis 11, and the compensation group G2 can also compensate the position change of the imaging surface 12 on the optical axis 11 while realizing the optical zoom function, so as to keep the position of the imaging surface 12 on the optical axis 11 relatively stable, and facilitate the realization of the zoom-in function, so that the zoom-in optical adapter 10 maintains good imaging quality in the zooming process. Meanwhile, the first lens L1 and the ninth lens L9 are arranged, the first lens L1 with negative focal power can well collect light and expand the aperture, the ninth lens L9 with positive focal power can effectively converge the light to the imaging surface 12, the adaptability of the zoom-in optical adapter 10 and the image side optical structure is improved, the effects of large aperture, high resolution and the like are achieved, and the accuracy of diagnosis and treatment is improved. In the present application, it is described that the anamorphic optical adapter 10 is capable of performing an anamorphic function, and it is understood that the position of the imaging surface 12 of the Ji Bianjiao optical adapter 10 on the optical axis 11 is relatively stable during the optical zoom process, for example, the position of the imaging surface 12 on the optical axis 11 remains stationary or the offset magnitude is sufficiently small.

The negative focal power of the first lens L1, the positive focal power of the variable magnification group G1, the negative focal power of the compensation group G2, and the positive focal power of the ninth lens L9 are matched, so that light can smoothly transition in the zoom optical adapter 10, which is beneficial to inhibiting generation of aberration, reducing sensitivity of aberration, and improving imaging quality. The negative focal power of the first lens L1, in combination with the concave design of the image side surface of the first lens L1, is beneficial to collecting light and diverging the light toward the image side, and improves the light incoming amount and aperture of the zoom optical adapter 10, and improves the imaging brightness and imaging quality. The positive focal power of the first cemented lens group L23 and the positive focal power of the fourth lens L4 in the zoom group G1 are matched with each other, so that light can be gently converged and transited towards the image side, the total length of the zoom optical adapter 10 is shortened, meanwhile, the light transition is gentle, aberration such as distortion of an edge view field is effectively restrained, the focal power and surface type design of the first lens L1 and the fifth lens L5 are matched, the light is filled with a pupil, the large aperture design is realized, the zoom optical adapter 10 can meet the requirement of relative illumination, the edge view field illumination is improved, and the imaging quality of the zoom optical adapter 10 in a weak light environment is improved. The negative focal power of the sixth lens L6 and the positive focal power of the second cemented lens group L78, in combination with the focal power designs of the fifth lens L5 and the zoom group G1, can smoothly transition light, correct aberration, reduce aberration sensitivity of the anamorphic optical adapter 10, improve imaging quality, and simultaneously, can reasonably diverge light to the image side to expand the aperture of the anamorphic optical adapter 10. The ninth lens element L9 has positive optical power, and is capable of converging light rays reasonably transiting from the object-side lens element towards the image plane 12, thereby improving the adaptability of the light rays to the image-side optical structure.

Thus, the Ji Bianjiao optical adapter 10 can obtain the effects of large aperture, miniaturization, high resolution, good imaging quality and the like.

In some embodiments, the second lens element L2 has positive refractive power, the object-side surface of the second lens element L2 is convex, the image-side surface of the second lens element L2 is concave, the third lens element L3 has positive refractive power, and both the object-side surface and the image-side surface of the third lens element L3 are convex. The seventh lens element L7 has negative refractive power, the object-side surface of the seventh lens element L7 is a plane, the image-side surface of the seventh lens element L7 is a concave surface, the eighth lens element L8 has positive refractive power, and both the object-side surface and the image-side surface of the eighth lens element L8 are convex surfaces. The design of gluing the seventh lens L7 and the eighth lens L8 is favorable for reasonably deflecting light rays, correcting Ji Bianjiao chromatic aberration, distortion and other aberration of the optical adapter 10 and improving imaging quality.

In the present application, the description of the bonding of two lenses is understood to describe the limitation of the relative positions of the two lenses, for example, the image side surface of one lens matches and abuts against the object side surface of the other lens, and the opposite surfaces of the two lenses are considered to overlap, and the two lenses are relatively fixed, but is not understood to be the limitation of the bonding process of the two lenses. The two lenses are glued by optical cement or are abutted and relatively fixed by other modes such as structural members, and the two lenses are in the scope of the application. In some embodiments, ji Bianjiao the lenses in the optical adapter 10 are coaxial, and the common axis of the lenses is the optical axis 11 of the system. In the present application, the object side of a certain lens is described, which is understood to be the surface of the lens facing away from the imaging surface 12, and the image side of a certain lens is described, which is understood to be the surface of the lens facing toward the imaging surface 12.

In some embodiments, ji Bianjiao the optical adapter 10 further comprises a stop 15, the stop 15 being arranged between the fifth lens L5 and the sixth lens L6, the stop 15 being capable of moving synchronously with the compensation group G2 on the optical axis 11. The diaphragm 15 is arranged between the fifth lens L5 and the sixth lens L6, and the focal power design of each lens of the variable magnification group G1 and the compensation group G2 is matched, so that the large aperture design is realized.

In some embodiments, the object-side surface of the first lens element L1 is concave, which is beneficial to improving the light collecting capability of the first lens element L1 and thus to increase the aperture in cooperation with the optical power and image-side surface type design of the first lens element L1. The object side surface of the fourth lens element L4 is convex, and the image side surface thereof is planar, which is beneficial to smooth transition of light rays, and the structural design of the compensation group G2 is also beneficial to the image side surface thereof being planar. The fifth lens element L5 has negative focal power, the object side surface and the image side surface of the fifth lens element L5 are both concave surfaces, the object side surface and the image side surface of the sixth lens element L6 are both concave surfaces, and the negative focal power of the sixth lens element L6 is matched, so that light can pass through the aperture 15, the light utilization efficiency is improved, and the large aperture design is realized. The object side surface and the image side surface of the ninth lens L9 are both convex surfaces, so that light can be effectively converged to the imaging surface 12, which is beneficial to adjusting the incident angle of the light on the imaging surface 12, improving the adaptability of the optical structure of the light and the image side, and further improving the resolution and the imaging quality of the zoom optical adapter 10.

In some embodiments, the object side surface and the image side surface of each lens in the Ji Bianjiao optical adapter 10 are spherical, and the material of each lens is glass, which is beneficial to the miniaturization design of the zoom optical adapter 10.

Referring to fig. 1 and 2, fig. 1 is a schematic structural view of an embodiment of the zoom optical adapter 10 in a wide-angle state, and fig. 2 is a schematic structural view of an embodiment of the zoom optical adapter 10 in a telephoto state. It can be seen that Ji Bianjiao the optical adapter 10 changes the effective focal length of the zoom optical adapter by movement of the variable magnification group G1 and the compensation group G2 along the optical axis 11 between the first lens L1 and the ninth lens L9, thereby realizing an optical zoom function.

Further, in some embodiments, as the variable magnification group G1 moves along the optical axis 11 in a direction toward the first lens L1 and away from the ninth lens L9, the effective focal length of the Ji Bianjiao optical adapter 10 gradually increases as the compensation group G2 moves along the optical axis 11 in a direction toward the first lens L1 and away from the ninth lens L9. Of course, depending on the design of each lens, there may be other correspondence between the effective focal length of the zoom optical adapter 10 and the movement of the zoom group G1 and the compensation group G2 along the optical axis 11, and in other embodiments, only one of the zoom group G1 and the compensation group G2 may move along the optical axis 11 when changing between the partial focal length states thereof. When the variable magnification group G1 moves along the optical axis 11, the first cemented lens group L23 and the fourth lens group L4 move synchronously along the optical axis 11, and when the compensation group G2 moves along the optical axis 11, the fifth lens group L5, the stop 15, the sixth lens group L6, and the second cemented lens group L78 move synchronously along the optical axis 11.

In some embodiments, the first lens L1 is capable of moving along the optical axis 11 at the object side of the variable magnification group G1 to achieve an optical focusing function. By the arrangement, the zooming and focusing functions of the zoom optical adapter 10 are not interfered with each other, so that the focusing function can be realized, the zoom function can be realized, the application range of the zoom optical adapter 10 is improved, the zoom optical adapter 10 can adapt to endoscope mirrors with different focal lengths, and good imaging quality can be obtained.

In some embodiments, the effective focal length of Ji Bianjiao optical adapter 10 is 17mm when Ji Bianjiao optical adapter 10 is in the wide-angle state, and the effective focal length of Ji Bianjiao optical adapter 10 is 31mm when Ji Bianjiao optical adapter 10 is in the tele state. Ji Bianjiao the optical adapter 10 may also include a mid state that is intermediate between the wide state and the tele state, and the effective focal length of the Ji Bianjiao optical adapter 10 may be 26mm when the Ji Bianjiao optical adapter 10 is in the mid state. Of course, the wide-angle state, the mid-focal state, and the telephoto state are only examples of three focal length states of the ziram optical adapter 10, and the effective focal length of the ziram optical adapter 10 may be any value between the wide-angle state and the telephoto state, for example, ji Bianjiao the effective focal length of the optical adapter 10 may be any value between 17mm and 31mm, depending on the difference in the positions of the zoom group G1 and the compensation group G2 on the optical axis 11.

In some embodiments, ji Bianjiao the optical adapter 10 satisfies the conditional expression: D1/TTL is more than or equal to 0.2 and less than or equal to 0.4; D2/TTL is more than or equal to 0.1 and less than or equal to 0.2; where D1 is the travel of the variable magnification group G1 on the optical axis 11, that is, the maximum moving distance of the variable magnification group G1 on the optical axis 11, D2 is the travel of the compensation group G2 on the optical axis 11, TTL is the total length of the zoom optical adapter 10, and when Ji Bianjiao of the optical adapter 10 is provided with the first protection element 13 and the second protection element 14, the total length of the Ji Bianjiao optical adapter 10 may be the distance between the object side surface of the first protection element 13 and the image side surface of the second protection element 14 on the optical axis 11. For example, D1/TTL can be 0.2, 0.3, or 0.4, and D2/TTL can be 0.1 or 0.2. In some embodiments, D1 may be a distance from the object side surface of the second lens element L2 in the wide-angle state to the object side surface of the second lens element L2 in the telephoto state on the optical axis 11, and D2 may be a distance from the object side surface of the fifth lens element L5 in the wide-angle state to the object side surface of the fifth lens element L5 in the telephoto state on the optical axis 11. When the above conditional expression is satisfied, the moving strokes of the zoom group G1 and the compensation group G2 on the optical axis 11 can be reasonably configured, so that the zoom group G1 and the compensation group G2 can be well matched, the optical zoom function is realized while maintaining good imaging quality, the zoom-in function is realized, in addition, the focal power design of each lens is matched, the large-range zooming is realized with smaller strokes, and the response speed and the zooming range of zooming are improved.

In some embodiments, ji Bianjiao the optical adapter 10 satisfies the conditional expression: 22-28% F1/CT 1; wherein F1 is the effective focal length of the first lens L1, and CT1 is the thickness of the first lens L1 on the optical axis 11. For example, |F1/CT1| can be 22, 23, 24, 25, 26, 27 or 28. When the above conditional expression is satisfied, the ratio of the effective focal length and the center thickness of the first lens L1 can be reasonably configured, so that the first lens L1 has enough negative focal power to collect incident light, which is favorable for realizing large aperture design, and meanwhile, the center thickness of the first lens L1 is not excessively large, which is favorable for shortening the total length of the zoom optical adapter 10, and in addition, the surface shape of the first lens L1 is not excessively curved, which is favorable for manufacturing and forming the first lens L1.

In some embodiments, ji Bianjiao the optical adapter 10 satisfies the conditional expression: f23 ∈5 CT23 is less than or equal to 7; wherein F23 is an effective focal length of the first cemented lens group L23, i.e. a combined focal length of the second lens element L2 and the third lens element L3, and CT23 is a thickness of the first cemented lens group L23 on the optical axis 11, i.e. a distance from an object side surface of the second lens element L2 to an image side surface of the third lens element L3 on the optical axis 11. For example, F23/CT23 may be 5, 5.2, 5.4, 5.5, 5.8, 6, 6.3, 6.7, 6.8, or 7. When the above conditional expression is satisfied, the ratio of the effective focal length to the center thickness of the first cemented lens group L23 can be reasonably configured, which is favorable for reasonably deflecting the light collected by the first lens L1, suppressing the generation of aberration, and simultaneously, is favorable for shortening the size of the first cemented lens group L23 on the optical axis 11, and is favorable for the miniaturized design of the zoom optical adapter 10.

In some embodiments, ji Bianjiao the optical adapter 10 satisfies the conditional expression: F4/F is more than or equal to 0.8 23 is less than or equal to 1.2; wherein F4 is an effective focal length of the fourth lens element L4, and F23 is an effective focal length of the first cemented lens group L23. For example, F4/F23 may be 0.8, 0.9, 1.0, 1.1 or 1.2. When the above conditional expression is satisfied, the ratio of the effective focal lengths of the fourth lens L4 and the first cemented lens group L23 can be reasonably configured, which is favorable for gently transiting light and reducing the bending degree of the light, thereby being favorable for reducing aberration sensitivity, improving imaging quality, preventing the surface shape of the lens from being excessively bent, reducing the design difficulty of the lens, improving the molding yield, and being favorable for realizing large aperture design.

In some embodiments, ji Bianjiao the optical adapter 10 satisfies the conditional expression: F5/CT5 is more than or equal to 10 and less than or equal to 11; wherein F5 is the effective focal length of the fifth lens L5, and CT5 is the thickness of the fifth lens L5 on the optical axis 11. For example, |f5/CT5| can be 10, 10.3, 10.5, 10.6, 10.8, or 11. When the above conditional expression is satisfied, the ratio of the effective focal length to the center thickness of the fifth lens L5 can be reasonably configured, so that the negative focal power of the fifth lens L5 can effectively disperse the light emitted from the variable magnification group G1 to the diaphragm 15, which is favorable for realizing large aperture design, and meanwhile, is favorable for preventing the surface of the fifth lens L5 from being excessively bent, reducing the design difficulty of the lens and improving the molding yield.

In some embodiments, ji Bianjiao the optical adapter 10 satisfies the conditional expression: f6 is more than or equal to 0.3% F5 is less than or equal to 0.4; wherein F6 is an effective focal length of the sixth lens L6, and F5 is an effective focal length of the fifth lens L5. For example, F6/F5 may be 0.3 or 0.4. When the above conditional expression is satisfied, the ratio of the effective focal lengths of the sixth lens L6 and the fifth lens L5 can be reasonably configured, so that the focal power distribution on both sides of the diaphragm 15 is reasonably configured, so that light can effectively pass through the diaphragm 15, a large aperture design is realized, aberration of an edge view field is favorably inhibited, and imaging quality is improved.

In some embodiments, ji Bianjiao the optical adapter 10 satisfies the conditional expression: F6/F78 is more than or equal to 0.5 and less than or equal to 0.6; wherein F6 is an effective focal length of the sixth lens L6, and F78 is an effective focal length of the second cemented lens group L78. For example, |f6/f78| may be 0.5 or 0.6. When the above conditional expression is satisfied, the ratio of the effective focal lengths of the sixth lens L6 and the second cemented lens group L78 can be reasonably configured, which is favorable for reasonably deflecting the light rays diverged by the sixth lens L6, correcting various aberrations while realizing a large aperture design, and improving the imaging quality of the zoom optical adapter 10.

In some embodiments, ji Bianjiao the optical adapter 10 satisfies the conditional expression: f9 is more than or equal to 10.5% CT9 is less than or equal to 11.5; wherein F9 is the effective focal length of the ninth lens L9, and CT9 is the thickness of the ninth lens L9 on the optical axis 11. For example, F9/CT9 may be 10.5, 10.7, 10.8, 11, 11.2 or 11.5. When the above conditional expression is satisfied, the ratio of the effective focal length to the center thickness of the ninth lens L9 can be reasonably configured, so that the ninth lens L9 can reasonably transition light toward the imaging surface 12, which is favorable for suppressing aberration, realizing large aperture characteristics while reducing ghost images, and being favorable for improving the relative illuminance of the zoom optical adapter 10 and the illuminance of the marginal field of view, thereby improving the imaging quality of the zoom optical adapter 10 in a low-light environment, and in addition, being favorable for improving the matching of light and the image side optical structure, thereby improving the imaging quality.

In some embodiments, the focal length of Ji Bianjiao optical adapter 10 varies from 17mm to 31mm, and the f-number of Ji Bianjiao optical adapter 10 ranges from 4.0 to 4.2 and the field angle ranges from 11 ° to 20 ° at each focal length state. Ji Bianjiao the optical adapter 10 has a sufficiently large zoom range, can promote the applicability of the zoom optical adapter 10, and can have a large aperture effect and good imaging quality in different focal length states.

Further, in some embodiments, the f-number FNO, the effective focal length f, the total length TTL, the maximum field angle FOV, the half image height IMH, the distance T1 on the optical axis 11 from the image side of the first lens L1 to the object side of the second lens L2, the distance T2 on the optical axis 11 from the image side of the fourth lens L4 to the object side of the fifth lens L5, and the distance T3 on the optical axis 11 from the image side of the eighth lens L8 to the object side of the ninth lens L9 of the optical adapter 10 in the wide-angle state, the mid-focal state, and the telephoto state are given in Table 1 below. The following data are satisfied, and the Ji Bianjiao optical adapter 10 can achieve a large aperture design, a compact design, a high resolution, and a good imaging quality in cooperation with the optical power and the surface configuration of each lens.

TABLE 1

Referring to fig. 1, 3-11, fig. 3 is a transfer function (MTF) graph of the zoom optical adapter 10 in the wide-angle state in some embodiments, fig. 4 is a defocus graph of the zoom optical adapter 10 in the wide-angle state in some embodiments, fig. 5 is a field curve graph and a distortion graph of the zoom optical adapter 10 in the wide-angle state in some embodiments, fig. 6 is a transfer function graph of the zoom optical adapter 10 in the mid-focus state in some embodiments, fig. 7 is a defocus graph of the zoom optical adapter 10 in the mid-focus state in some embodiments, fig. 8 is a field curve graph and a distortion graph of the zoom optical adapter 10 in the mid-focus state in some embodiments, fig. 9 is a transfer function graph of the zoom optical adapter 10 in the telephoto state in some embodiments, fig. 10 is a field curve graph and a distortion graph of the zoom optical adapter 10 in the telephoto state in some embodiments, and fig. 11 is a field curve graph and a distortion graph of the zoom optical adapter 10 in the telephoto state in some embodiments. As can be seen from fig. 3 to 11, when the optical adapter 10 of Ji Bianjiao meets 200lp/mm in resolution in different focal length states, the MTF value of the central field of view is greater than 0.3, and the speckle in the point column diagram of the central field of view of the zoom optical adapter 10 is smaller than Yu Aili speckle, so that the aberration such as curvature of field and distortion of the optical adapter 10 of Ji Bianjiao is effectively corrected, and the optical adapter 10 can have high resolution and good imaging quality in different focal length states.

In some embodiments, ji Bianjiao the optical adapter 10 satisfies the data of table 2 below, and the effects that can be obtained from satisfying the following data can be obtained from the above description.

TABLE 2

In some embodiments, the present application also provides a medical endoscope, including a fixing member, and the zoom optical adapter 10, ji Bianjiao optical adapter 10 according to any one of the above embodiments is provided on the fixing member. Ji Bianjiao the optical adapter 10 can be used as an optical adapter of a medical endoscope, the fixing piece can be a mechanical structure for supporting the zoom optical adapter 10, the medical endoscope can further comprise a camera and an endoscope mirror, and the zoom optical adapter 10 can be arranged between the camera and the endoscope mirror so as to adjust images collected by the endoscope mirror and then shoot the images onto the camera, and the imaging quality of the medical endoscope is improved. The above-mentioned zoom optical adapter 10, ji Bianjiao is adopted in the medical endoscope, the optical adapter 10 has the effects of large aperture, miniaturization, good imaging quality and the like, has enough zoom range, is favorable for the assembly of the zoom optical adapter 10 in the medical endoscope, is favorable for reducing the volume of the medical endoscope, and improves the imaging quality of the medical endoscope, thereby being favorable for improving the application range and optical performance of the medical endoscope and the accuracy of diagnosis and treatment.

The technical features of the above-described embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above-described embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.

The above examples illustrate only a few embodiments of the application, which are described in detail and are not to be construed as limiting the scope of the claims. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the application, which are all within the scope of the application. Accordingly, the scope of protection of the present application is to be determined by the appended claims.

Claims (10)

1. A zoom-in optical adapter, comprising, in order from an object side to an image side along an optical axis:

a first lens having negative optical power, an image side surface of the first lens being a concave surface;

The variable magnification group with positive focal power sequentially comprises a second lens, a third lens and a fourth lens with positive focal power from an object side to an image side along an optical axis, and the second lens and the third lens are glued to form a first glued lens group with positive focal power;

The optical lens comprises a compensation group with negative focal power, wherein the compensation group sequentially comprises a fifth lens, a sixth lens with negative focal power, a seventh lens and an eighth lens from an object side to an image side along an optical axis, and the seventh lens and the eighth lens are glued to form a second glued lens group with positive focal power;

A ninth lens having positive optical power;

The variable magnification group and the compensation group are movable along an optical axis between the first lens and the ninth lens to achieve an optical zoom function.

2. The anamorphic optical adapter of claim 1, wherein the Ji Bianjiao optical adapter satisfies the following condition:

0.2≤（D1/TTL）≤0.4；

0.1≤（D2/TTL）≤0.2；

Wherein D1 is the stroke of the variable magnification group on the optical axis, D2 is the stroke of the compensation group on the optical axis, and TTL is the total length of the Ji Bianjiao optical adapter.

3. The anamorphic optical adapter of claim 1, wherein the Ji Bianjiao optical adapter satisfies the following condition:

22≤|F1/CT1|≤28；

wherein F1 is the effective focal length of the first lens, and CT1 is the thickness of the first lens on the optical axis.

4. The anamorphic optical adapter of claim 1, wherein the Ji Bianjiao optical adapter satisfies the following condition:

5≤F23/CT23≤7；

Wherein F23 is the effective focal length of the first cemented lens group, and CT23 is the thickness of the first cemented lens group on the optical axis.

5. The anamorphic optical adapter of claim 1, wherein the Ji Bianjiao optical adapter satisfies the following condition:

0.8≤F4/F23≤1.2；

Wherein F4 is an effective focal length of the fourth lens, and F23 is an effective focal length of the first cemented lens group.

6. The anamorphic optical adapter of claim 1, wherein the Ji Bianjiao optical adapter satisfies the following condition:

F5/CT5 is more than or equal to 10 and less than or equal to 11; and/or the number of the groups of groups,

10.5≤F9/CT9≤11.5；

Wherein F5 is an effective focal length of the fifth lens, CT5 is a thickness of the fifth lens on an optical axis, F9 is an effective focal length of the ninth lens, and CT9 is a thickness of the ninth lens on the optical axis.

7. The anamorphic optical adapter of claim 1, wherein the Ji Bianjiao optical adapter satisfies the following condition:

F6 is more than or equal to 0.3% F5 is less than or equal to 0.4; and/or the number of the groups of groups,

0.5≤|F6/F78|≤0.6；

Wherein F6 is an effective focal length of the sixth lens, F5 is an effective focal length of the fifth lens, and F78 is an effective focal length of the second cemented lens group.

8. The anamorphic optical adapter of claim 1, wherein the first lens is movable along an optical axis on an object side of the variable magnification group to achieve an optical focusing function;

And/or, the Ji Bianjiao optical adapter further comprises a diaphragm, the diaphragm is arranged between the fifth lens and the sixth lens, and the diaphragm can synchronously move along an optical axis along with the compensation group.

9. The anamorphic optical adapter of claim 1, wherein the first lens has a concave object-side surface; and/or the number of the groups of groups,

The second lens has positive focal power, the object side surface of the second lens is a convex surface, the image side surface of the second lens is a concave surface, the third lens has positive focal power, and the object side surface and the image side surface of the third lens are both convex surfaces; and/or the number of the groups of groups,

The object side surface of the fourth lens is a convex surface, and the image side surface is a plane; and/or the number of the groups of groups,

The fifth lens has negative focal power, and both the object side surface and the image side surface of the fifth lens are concave surfaces; and/or the number of the groups of groups,

The object side surface and the image side surface of the sixth lens are concave surfaces; and/or the number of the groups of groups,

The seventh lens is provided with negative focal power, the object side surface of the seventh lens is a plane, the image side surface of the seventh lens is a concave surface, the eighth lens is provided with positive focal power, and the object side surface and the image side surface of the eighth lens are both convex surfaces; and/or the number of the groups of groups,

The object side surface and the image side surface of the ninth lens are both convex surfaces.

10. A medical endoscope comprising the anamorphic optical adapter of any one of claims 1-9.