Disposable rigid tube endoscope

Abstract

The disposable hard tube endoscope body of the present invention is composed of an objective lens and three groups of 1:1 symmetrical image transfer systems with the same optical structure. The aforementioned objective lens includes a sapphire protective film, a plano-concave lens, an aperture piece, a turning prism, and a plano-convex lens. The five optical parts are glued together according to the design requirements to form the first component of the objective lens; the aforementioned objective lens includes a plano-concave lens and a plano-convex lens, and the two are glued together to form the second component of the objective lens; the aforementioned three groups of 1:1 symmetrical image transfer systems with the same optical structure are composed of 6 double convex thick lenses with exactly the same optical structure parameters, and their front and rear focal points are connected to transmit the image of the objective lens to the image side focal plane of the last group of 1:1 symmetrical image transfer systems. The aforementioned disposable hard tube endoscope body contains an eyepiece and an eye mask, and the end is a cone surface, which is connected to a special CMOS camera interface for use.

Description

Technical Field

[0001] The present invention belongs to the technical field of optical design, and specifically relates to a disposable rigid tube endoscope body and an optical system design method thereof. The rigid tube endoscope designed by the design method has an objective lens and three sets of image transfer systems forming the rigid tube endoscope body. Aberrations such as spherical aberration, chromatic aberration, and field curvature that cannot be corrected by the optical system of the rigid tube endoscope body are corrected by a subsequent CMOS camera imaging system. Background Art

[0002] like Figure 1 As shown, the existing rigid endoscope optical system includes three parts: OBJ is the rigid endoscope objective lens, which forms an inverted image of the object; REL is the rigid endoscope optical image transfer system, which re-images the image formed by the objective lens in a 1:1 ratio, and finally forms an upright real image at the object focal plane of the rigid endoscope eyepiece after multiple image transfers, and its function is to increase the working length of the rigid endoscope; OCU is the rigid endoscope eyepiece, which images the endoscope image at infinity, and the observer can observe the aforementioned upright real image through it.

[0003] Figure 2 This is the structure diagram of the existing rigid tube endoscope optical image transfer system. This structure consists of a pair of double-cemented thin lens groups with the same structural parameters. The aperture is located in the middle, and the vertical axis aberration is well corrected. However, due to the use of thin lens groups, the system light energy transmittance is low, and the lens is easy to tilt during assembly, which affects the image quality. No company is using it now.

[0004] Figure 3 The existing rigid tube endoscope optical image transfer system shown is a symmetrical structure, in which one end of the Hopkins rod lens is glued to a thin negative lens with a negative focal length. The thin negative lens uses optical glass with a high refractive index and high dispersion to correct axial chromatic aberration, but cannot correct field curvature. The advantage of this rigid tube endoscope optical image transfer system is its simple structure, but its disadvantage is that the radius of the non-glued surface of the Hopkins rod lens is large, and it is difficult to process using traditional optical processing technology.

[0005] Figure 4 The structure of the existing rigid tube endoscope optical image transfer system is shown, in which the two ends of the Hopkins rod lens are glued to the Bo lens. The Hopkins rod lens has a small spherical radius and is easy to process, but has many glued surfaces and is time-consuming. At the same time, the eccentricity of the glued surface seriously affects the image quality.

[0006] Figure 5 The existing rigid tube endoscope optical image transfer system shown in the figure uses only two symmetrical Hopkins rod lenses, which have the least number of lenses and cannot correct any aberrations. The spherical radius is large and the processing difficulty is very high, so it cannot be widely used by enterprises at present.

[0007] At present, the optical system of rigid tube endoscopes consists of an eyepiece, 3 or 5 sets of image transfer systems and an eyepiece group. The structure is duplicated, the cost is high, and it cannot be used once.

[0008] The technical problem to be solved by the present invention is: to minimize the cost of the disposable hard tube endoscope body by designing the least number of lenses. The spherical aberration, coma, field curvature and other aberrations existing in the traditional hard tube endoscope body optical system composed of an objective lens and three groups of 1:1 symmetrical image transfer systems with the same optical structure are not corrected, the eyepiece and eye mask are eliminated, the end of the hard tube endoscope body is a cone surface, and it is used in conjunction with a special CMOS interface. Summary of the invention

[0009] The technical problem to be solved by the present invention is: a hard tube endoscope body consisting of an objective lens and three groups of 1:1 symmetrical image transfer systems with the same optical structure makes the disposable hard tube endoscope body have the lowest cost and the simplest structure.

[0010] The technical solution of the present invention is as follows:

[0011] The disposable rigid tube endoscope body, which is composed of an objective lens and three groups of 1:1 symmetrical image rotation systems with the same optical structure, can meet the 175mm working length requirement of arthroscopy and sinusoscope. Since the aberration is not corrected and there is no eyepiece, it cannot be used alone. It needs to be coordinated with the CMOS camera imaging system and computer software designed in the present invention. After the field of view direction of the rigid tube endoscope is calibrated, it can be put into normal operation.

[0012] The optical system of the disposable hard tube endoscope in the present invention has three groups of 1:1 symmetrical image transfer systems with the same optical structure, which are composed of six biconvex thick lenses with the same spherical radius. The objective lens and the three groups of 1:1 symmetrical image transfer systems with the same optical structure constitute the hard tube endoscope body, which is suitable for sinusoscopes, arthroscopes, etc. The image transfer system composed of three groups of 1:1 symmetrical image transfer systems with the same optical structure can only image the image of the objective lens located at the front focus of the first group of image transfer systems at the rear focus of the last group of image transfer systems after passing through the three groups of image transfer systems. At this time, any aberration cannot be well corrected, and its aberration is corrected by the subsequent CMOS camera imaging system. The CMOS camera imaging system consists of a collimating lens group and an imaging lens group. The collimating lens group images the image of the image transfer system at infinity, and at the same time corrects aberrations such as spherical aberration, coma, and field curvature that cannot be corrected by the rigid tube endoscope optical system composed of the objective lens and three groups of image transfer systems; the imaging lens group of the CMOS camera imaging system converges the image of the CMOS camera imaging system collimating lens group at infinity on the CMOS image plane, and further corrects the residual aberration of the optical system in front of it to obtain an ideal image. In order to calibrate the field of view direction of the rigid tube endoscope, the method of controlling the image display range by computer software is used to limit the field of view display range of the rigid tube endoscope and provide a direction indicator function.

[0013] The beneficial effects of the present invention are:

[0014] 1) The optical system of the disposable hard tube endoscope of the present invention has a small number of lenses, no eyepiece and eye mask, simple structure and low cost.

[0015] 2) The CMOS camera imaging system of the present invention can effectively correct various aberrations of the optical system of the disposable hard tube endoscope body to obtain a clear image.

[0016] 3) The disposable hard tube endoscope body of the present invention can be used once or repeatedly;

[0017] 4) The CMOS camera imaging system of the present invention replaces the traditional interface lens structure, saving a large number of eyepieces and eye masks.

[0018] 5) Electronic field diaphragm saves the cost of mechanical field diaphragm and has a simpler mechanical structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural diagram of the optical system of an existing three-section rigid tube endoscope.

[0020] Figure 2 The schematic diagram is a structural principle diagram of an existing rigid tube endoscope optical image transfer system.

[0021] Figure 3 The invention is structure 1 of the existing rigid tube endoscope optical image transfer system.

[0022] Figure 4 The present invention is structure 2 of the existing optical image transfer system of a rigid tube endoscope.

[0023] Figure 5 The present invention is structure three of the existing rigid tube endoscope optical image transfer system.

[0024] Figure 6a This is the overall structural diagram of the disposable hard tube endoscope body of the present invention.

[0025] Figure 6b This is a structural diagram of the 0° direct-view endoscope objective lens of the present invention.

[0026] Figure 6c It is a structural diagram of the 30° oblique viewing objective lens of the present invention.

[0027] Figure 6d It is a structural diagram of a 70° oblique viewing objective lens of the present invention.

[0028] Figure 6e It is a structural diagram of three groups of image transfer systems of the present invention.

[0029] Figure 7a This is an optical structure diagram of the CMOS camera imaging system of the present invention.

[0030] Figure 7b This is a structural diagram of the collimating lens group of the CMOS camera imaging system of the present invention.

[0031] Figure 7c This is a structural diagram of the imaging lens group of the CMOS camera imaging system of the present invention.

[0032] Figure 8 It is the imaging diagram of the present invention after being processed by computer software.

[0033] Fig. 9 It is a schematic diagram of the structure of a disposable hard tube endoscope.

[0034] Fig.10 This is the mechanical structure diagram of the CMOS camera imaging system DETAILED DESCRIPTION

[0035] Disposable hard tube endoscope body Figure 6a As shown, it is composed of an objective lens and three groups of 1:1 symmetrical image transfer systems with the same optical structure. Among them, 1-1 is a sapphire protective film, 1-2 is a plano-concave lens, 1-3 is an aperture piece, 1-5 is a turning prism, and 1-5 is a plano-convex lens. The five optical parts are glued together according to the design requirements to form the first component of the objective lens; 2-1 is a plano-concave lens, and 2-2 is a plano-convex lens. The two are glued together to form the second component of the objective lens; 3-1, 3-2, 3-3, 3-4, 3-5, and 3-6 are double convex thick lenses with exactly the same structural parameters. Their front and rear focal points are connected to form three groups of 1:1 symmetrical image transfer systems with the same optical structure. The front focal point of 3-1 coincides with the position of the objective image plane Image. Image1, Image2, and Image3 are the images formed by the three groups of image transfer systems, and Image3 is located at the back focal point of the 3-6 double convex thick lens.

[0036] Figure 6b It is a 0° direct-view endoscope objective structure, which does not contain prisms 1-4; Figure 6c It is a 30° oblique objective lens structure; Figure 6d It is a 70° oblique objective lens structure; Figure 6e This is a structural diagram of the three-group image transfer system.

[0037] The various aberrations of the disposable rigid tube endoscope body, which is composed of an objective lens and three groups of 1:1 symmetrical image transfer systems with the same optical structure, have not been corrected. After adding the CMOS camera imaging system, the aberrations have been well corrected. Image 3 is imaged at infinity by the collimating lens group of the CMOS camera imaging system, and Image 4 is the image formed by the imaging lens group of the CMOS camera imaging system on the CMOS image plane.

[0038] Figure 7a This is the optical structure diagram of the CMOS camera imaging system. Figure 7bThis is the structure diagram of the collimating lens group of the CMOS camera imaging system. Figure 7c This is a structural diagram of the imaging lens group of a CMOS camera imaging system.

[0039] Figure 8 Computer software is used to not display pixels outside the 3.2mm diameter range of the CMOS center, and the disposable hard tube endoscope image is displayed within the 3.2mm diameter range, and a direction indicator is set. In order to obtain a clear optical image, the imaging lens group of the CMOS camera imaging system can be fine-focused along the optical axis.

[0040] Fig. 9 This is a schematic diagram of the structure of a disposable hard tube endoscope. Figure 6a The optical system lenses of the disposable hard tube endoscope body shown are sequentially assembled in the inner tube 6-2 of the disposable hard tube endoscope; an illumination optical fiber is assembled between the inner tube 6-2 and the outer tube 6-1, and the other end of the illumination optical fiber passes through the incident end of the illumination optical fiber bundle connecting sleeve 6-4, and the optical fiber end face is polished; the main body 6-3 and the outer tube 6-1 are laser sealed and welded; the main body 6-3 and the illumination optical fiber bundle connecting sleeve 6-4 are laser sealed and welded or epoxy glue is used; the main body 6-3 and the end sealing sleeve 6-5 are laser sealed and welded; the end protection sheet 6-6 and the end sealing sleeve 6-5 are epoxy glue sealed and bonded; the end sealing sleeve 6-5 and the disposable hard tube endoscope body fixing part 6-7 are laser sealed and welded, and the relative position between the two is adjusted during welding to make the image clear, and the positioning pin 6-8 is press-fitted with the disposable hard tube endoscope body fixing part 6-7 to determine the direction of the hard tube endoscope body.

[0041] Fig.10 It is a mechanical structure diagram of the CMOS camera imaging system. The locking ring 7-1 locks the conical surface between the disposable hard tube endoscope body fixing part 6-7 and the CMOS camera imaging system body 7-3. The positioning pin 6-8 is in the crescent groove of the CMOS camera imaging system body 7-3, which plays a limiting role. The CMOS camera imaging system body 7-3 is connected to the CMOS camera. The lenses of the collimating lens group of the CMOS camera imaging system are sequentially assembled in the straight lens group barrel 7-2. The lenses of the imaging lens group of the CMOS camera imaging system are sequentially assembled in the imaging lens group barrel 7-4. The straight lens group barrel 7-2 and the imaging lens group barrel 7-4 are sequentially assembled in the CMOS camera imaging system body 7-3. In order to adjust the position of the imaging lens group lens, a focusing mechanism can be added, which is omitted here.

[0042] The CMOS camera imaging system of the present invention replaces the traditional interface lens structure, saving a large number of eyepieces and eye masks while being able to correct the spherical aberration, chromatic aberration and field curvature of the traditional hard tube endoscope body optical system. Combined with the use of an electronic field diaphragm, the cost of a mechanical field diaphragm is saved and the mechanical structure is simpler.

Claims

1. A disposable hard tube endoscope, characterized in that: The invention comprises a hard tube endoscope body, which is composed of an objective lens and three groups of 1:1 symmetrical image transfer systems with the same optical structure. The objective lens comprises a first group of objective lens components and a second group of objective lens components. The first group of objective lens components is composed of a sapphire protective film (1-1), a plano-concave lens (1-2), an aperture piece (1-3), a prism (1-4), and a plano-convex lens (1-5) which are adjacent to each other in sequence. The sapphire protective film (1-1), the plano-concave lens (1-2), the aperture piece (1-3), the prism (1-4), and the plano-convex lens (1-5) are bonded together with ultraviolet photosensitive adhesive. The second group of objective lens is composed of a meniscus lens (2-1) and a biconvex lens (2-2), which are bonded together with ultraviolet photosensitive adhesive. The objective lens does not contain an eyepiece, a field aperture, an eye mask, or a light cone. The end of the hard tube endoscope body is a cone surface which is used in conjunction with a special CMOS camera interface lens.

2. The disposable hard tube endoscope according to claim 1, characterized in that: The three groups of 1:1 symmetrical image transfer systems with the same optical structure are composed of six double convex thick lenses (3-1, 3-2, 3-3, 3-4, 3-5, 3-6) with the same spherical radius and center thickness, and the front focus and the rear focus are overlapped in sequence along the light propagation direction.

3. The disposable hard tube endoscope according to claim 2, characterized in that: The front focus of the biconvex thick lens (3-1) coincides with the position of the object image plane.

4. A sinusoscope or arthroscopy, characterized in that: Using a disposable hard tube endoscope as described in any one of claims 1 to 3, The optical system lenses of the disposable hard tube endoscope body are sequentially assembled in the inner tube (6-2) of the disposable hard tube endoscope; an illuminating optical fiber is assembled between the inner tube (6-2) and the outer tube (6-1); the other end of the illuminating optical fiber passes through the incident end of the illuminating optical fiber bundle connecting sleeve (6-4), and the optical fiber end face is polished; the main body (6-3) and the outer tube (6-1) are laser sealed and welded; the main body (6-3) and the illuminating optical fiber bundle connecting sleeve (6-4) are laser sealed and welded or epoxy glue is used; the main body (6-3) and the end sealing sleeve (6-5) are laser sealed and welded; the end protection sheet (6-6) and the end sealing sleeve (6-5) are epoxy glue sealed and bonded; the end sealing sleeve (6-5) and the disposable hard tube endoscope body fixing piece (6-7) are laser sealed and welded, and the relative position between the two is adjusted during welding to make the image clear, and the positioning pin (6-8) is press-fitted with the disposable hard tube endoscope body fixing piece (6-7). The locking ring (7-1) locks the conical surface between the disposable hard tube endoscope body fixing part (6-7) and the CMOS camera imaging system body (7-3); the positioning pin (6-8) is in the crescent groove of the CMOS camera imaging system body (7-3) to play a limiting role; the CMOS camera imaging system body (7-3) is connected to the CMOS camera; the lenses of the collimating lens group of the CMOS camera imaging system are sequentially assembled in the straight lens group barrel (7-2); the lenses of the imaging lens group of the CMOS camera imaging system are sequentially assembled in the imaging lens group barrel (7-4); the straight lens group barrel (7-2) and the imaging lens group barrel (7-4) are sequentially assembled in the CMOS camera imaging system body (7-3).

Images