CN111158137A

CN111158137A - Coaxial illumination fiber endoscope

Info

Publication number: CN111158137A
Application number: CN201811318180.2A
Authority: CN
Inventors: 刘小华; 聂玉奎; 娄正林; 郭大为
Original assignee: Wti Beijing Asia Pacific Photoelectric Instrument Co ltd
Current assignee: Wti Beijing Asia Pacific Photoelectric Instrument Co ltd
Priority date: 2018-11-07
Filing date: 2018-11-07
Publication date: 2020-05-15

Abstract

The invention provides a coaxial illuminating fiber endoscope, which comprises an outer endoscope tube, an illuminating optical fiber, a protection sheet, an optical fiber image transmission bundle, an objective lens group, an eyepiece group, a main endoscope body and a beam splitter. The outer lens tube is used as a common propagation channel of the illumination light beam and the imaging light beam, the diameters of the objective lens group and the optical fiber image transmission beam are approximately equal to the diameter of the inner wall of the outer lens tube, and the objective lens group and the eyepiece lens group are manufactured by adopting a precision die pressing process. The implementation mode can reduce the size of the endoscope and improve the imaging resolution of the endoscope.

Description

Coaxial illumination fiber endoscope

Technical Field

The invention belongs to the technical field of endoscopes, and particularly relates to a coaxial illumination fiber endoscope.

Background

Endoscopes have found wide application in the medical and scientific research fields. Among them, the fiberscope is a mainstream product for realizing imaging of internal tissues of a pore canal with the diameter of less than 1mm, and has irreplaceable significance. In the future, the development direction of fiberscope products can be generalized to two core problems: 1. how to improve the imaging quality and observe more details of the tissue surface; 2. how to reduce manufacturing cost, realize disposable, avoid because the disinfection thoroughly arouses the risk of cross infection.

The structure that the illumination channel and the imaging beam channel are separated from each other is a very serious defect for the existing fiber endoscope product. As shown in fig. 1, the structure of the existing optical fiber endoscope includes an outer lens tube, an illumination optical fiber disposed along an inner wall of the outer lens tube, an optical fiber image transmission bundle disposed inside the outer lens tube, an objective lens group disposed at a front end of the optical fiber image transmission bundle, a main lens body disposed at a rear end of the outer lens tube, and an eyepiece group disposed inside the main lens body and at a rear end of the optical fiber image transmission bundle; the front-end optical elements and the enlarged schematic structure of the front-end optical elements are shown in fig. 2, and the structure has the defect that the illumination fiber channel occupies the space of the imaging beam channel, so that the actual light passing diameter is greatly different from the diameter of the probe part (the diameter of the outer lens tube), and the following problems can be caused: if the resolution is improved, the size of the inner lens tube is increased, and the size of the outer lens tube is increased at the same time, so that the high-resolution endoscope cannot be inserted into a small pore passage for examination. Therefore, the image quality of the existing fiber endoscope product has a serious restriction relation with the use occasion, and meanwhile, the installation process of the illumination optical fiber used for transmitting the illumination light beam is complex, the assembly efficiency is low, and the cost is indirectly improved.

In addition, the objective lens system of the existing fiber endoscope product is a gradient Index (GRIN) lens, and the lens needs to be manufactured by a special process, so that the efficiency is low and the cost is high. The eyepiece lens system is a spherical glass lens, and is usually manufactured by a classical grinding and polishing process, and the efficiency and quality of batch production of the eyepiece lens system cannot be compared with those of a modern manufacturing process, so that the manufacturing cost is also higher.

Due to the defects, the resolution of the existing fiber endoscope product is limited, and the existing fiber endoscope product is not provided with a disposable condition due to higher cost. From another perspective, it can be appreciated that if an appropriate solution could be found to overcome the above-mentioned drawbacks, great impetus would be given to the development of fiberscope products.

Disclosure of Invention

In view of the above, the present invention provides a coaxial illumination fiber endoscope, which can reduce the size of the endoscope and improve the imaging resolution of the endoscope.

The present invention has the following advantageous effects.

1. The coaxial illumination fiber endoscope provided by the invention takes the outer endoscope tube as a common propagation channel of an illumination light beam and an imaging light beam, and an independent channel is not required to be arranged for installing the illumination optical fiber, so that the diameter of a front end optical element can be increased and is approximately equal to the inner diameter of the outer endoscope tube. On the premise of keeping the size of the outer lens tube unchanged, the resolution ratio can be improved to the maximum extent, so that more details on the surface of the tissue can be observed; the diameter of the endoscope tube can be reduced under the condition that the prior resolution ratio is not changed, and the diameter of the outer endoscope tube of the fiber endoscope is reduced to be approximately equal to the diameter of the front-end optical element of the prior fiber endoscope, so that the fiber endoscope can be used for observing pathological changes in a tiny pore channel which cannot be penetrated by the prior fiber endoscope, and the application field of instruments is widened.

2. According to the coaxial illumination fiber endoscope, the illumination optical fiber is not required to be installed, the material expenditure is saved, the assembly efficiency is improved, and the manufacturing cost is reduced.

3. The coaxial illumination fiber endoscope adopts the aspheric surface-shaped lens group manufactured by the precision die pressing process as the objective lens system and the eyepiece lens system, has the characteristics of high image quality and high batch production efficiency, further reduces the manufacturing cost, enables the fiber endoscope to have the condition of one-time use, and avoids the risk of cross infection in the inspection process.

Drawings

Fig. 1 is a schematic view of a prior art fiberscope product.

Fig. 2 is an enlarged schematic view of the front end optical element and the structure of a conventional fiber endoscope product.

FIG. 3 is a schematic view of a coaxially illuminated fiberscope according to the present invention.

FIG. 4 is an enlarged view of the optical elements at the front end of the coaxial illuminating fiberscope and the structure thereof.

Wherein, the device comprises 1-an external lens tube, 2-an illuminating optical fiber, 3-a protective plate, 4-an optical fiber image transmission beam, 5-an objective lens group, 6-an eyepiece lens group, 7-a main lens body and 8-a beam splitter.

Detailed Description

The invention is described in detail below by way of example with reference to the accompanying drawings.

The invention discloses a coaxial illumination fiber endoscope, which is shown in attached figures 3 and 4 and comprises an outer endoscope tube 1, a protective sheet 3, an optical fiber image transmission bundle 4, a main endoscope body 7, an objective lens group 5, an eyepiece group 6 and a beam splitter 8; the beam splitter 8 is positioned in the main lens body 7 between the rear end of the optical fiber image transmission beam 4 and the eyepiece group; the beam splitter 8 is used for sending an external illumination light source into the optical fiber image transmission beam 4, and the illumination light source is transmitted to the front end of the optical fiber image transmission beam 4 and then irradiates a detection target through the objective lens group 5; the detection target reflects or scatters light back to the endoscope, and the light is sent to the eyepiece group 7 by the beam splitter 8 after sequentially passing through the objective group 5 and the optical fiber image transmission beam 4, and finally is emergent to enter a visual or television observation system.

The invention does not adopt the traditional optical fiber illumination, but introduces the illumination light into the optical fiber image transmission beam through the beam splitter 8 to directly illuminate the detection target, and then the optical fiber image transmission beam 4 images the detection target, simultaneously realizes illumination and imaging, cancels the illumination light path, thereby increasing the diameter of the front end optical element and being approximately equal to the inner diameter of the outer lens tube. On the premise of keeping the size of the outer lens tube unchanged, the resolution ratio can be improved to the maximum extent, so that more details on the surface of the tissue can be observed; the diameter of the endoscope tube can be reduced under the condition that the prior resolution ratio is not changed, and the diameter of the outer endoscope tube of the fiber endoscope is reduced to be approximately equal to the diameter of the front-end optical element of the prior fiber endoscope, so that the fiber endoscope can be used for observing pathological changes in a tiny pore channel which cannot be penetrated by the prior fiber endoscope, and the application field of instruments is widened.

It should be noted that the objective lens group 5 and the ocular lens group 6 of the present invention can be aspheric surface-shaped lens groups, and the material can be optical glass or optical plastic, and the objective lens group and the ocular lens group are manufactured by a precision molding process, so that the imaging quality can be improved, and the cost can be reduced.

The beam splitter 8 may be in the form of a beam splitter plate or a beam splitter prism.

The outer lens tube 1 is made of stainless steel or high polymer materials, and the following elements are installed inside the outer lens tube: an optical fiber image transmission bundle 4, an objective lens group 5 and a protection sheet 3.

The diameter of the optical fiber image transmission bundle 4 is approximately equal to the diameter of the inner wall of the outer lens tube 1.

The main lens body 7 is made of stainless steel or high polymer material, is connected with the outer lens tube 1, and is internally provided with a beam splitter 8.

The front end of the outer lens tube 1 is also provided with a protection plate 3.

In summary, the above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A coaxial lighting fiber endoscope comprises an outer endoscope tube (1), an optical fiber image transmission bundle (4), a main endoscope body (7), an objective lens group (5) and an eyepiece lens group (6), and is characterized by further comprising a beam splitter (8); the beam splitter (8) is positioned in the main lens body (7) between the rear end of the optical fiber image transmission beam (4) and the eyepiece group (6); the beam splitter (8) is used for sending external illumination light into the optical fiber image transmission bundle (4) and sending reflected light received from a detection target through the optical fiber image transmission bundle (4) into the eyepiece group 7.

2. A coaxially illuminated fiberscope according to claim 1, wherein said objective lens group (5) and said eyepiece lens group (6) are aspheric lens groups.

3. A coaxially illuminated fibre endoscope according to claim 1, characterized in that the material of said objective (5) and eyepiece (6) groups is optical glass or optical plastic.

4. A coaxially illuminated fiber endoscope according to claim 1, characterized in that said objective lens group (5) and said eyepiece lens group (6) are manufactured by means of a precision molding process.

5. A coaxial illumination fiber endoscope as defined in claim 1 wherein said beam splitter 10 is a beam splitter or a beam splitter prism.

6. A coaxially illuminated fibre endoscope according to claim 1, characterized in that the material of the outer tube (1) is stainless steel or a polymer material.

7. A coaxially illuminated fibre endoscope according to claim 1, characterized in that the material of the main endoscope body (7) is stainless steel or a polymer material.

8. A coaxially illuminated fibre endoscope according to claim 1, characterized in that the front end of the outer tube (1) is further provided with a protective sheet (3).

9. A coaxially illuminated fibre endoscope according to claim 1, characterized in that the diameter of the fibre optic image bundle (4) is approximately equal to the inner diameter of the outer lens tube (1).