CN210572987U

CN210572987U - Large-view-field miniature endoscope

Info

Publication number: CN210572987U
Application number: CN201921247897.2U
Authority: CN
Inventors: 不公告发明人
Original assignee: Suzhou Yibolun Photoelectric Instrument Co Ltd
Current assignee: Suzhou Yibolun Photoelectric Instrument Co Ltd
Priority date: 2019-01-23
Filing date: 2019-08-02
Publication date: 2020-05-19
Anticipated expiration: 2029-08-02
Also published as: CN111474694A; CN210155407U; CN111474695A; CN211086790U; CN210155404U; CN210166557U; CN110794565A; CN111474696A; CN210155401U

Abstract

The utility model relates to a medical diagnosis imaging device technical field, concretely relates to miniature endoscope of big visual field, including miniature probe, miniature probe include the shell, with the fixed objective of shell and locate the scanner in the shell, objective is located outside the objective lens body according to the back focal plane that arouses light wavelength calculation, and the scanner is located the back focal plane position department of objective. The back focal plane of this scheme objective is located outside the mirror body to set up the scanner through the back focal plane at objective, under the unchangeable prerequisite of keeping incident beam diameter, increase angle of vision reduces the volume of the miniature probe of endoscope, has solved among the prior art and has caused objective and the problem that miniature probe volume increases for realizing big visual field.

Description

Large-view-field miniature endoscope

Technical Field

The utility model relates to a medical diagnosis imaging device technical field, concretely relates to miniature endoscope of big visual field.

Background

With the development of science and technology, medical endoscopes have been widely used in the medical field, and are one of the important tools for human body to peep and treat organs in the human body. The structure of the endoscope is greatly improved four times in the development process of over 200 years, and the image quality of the endoscope from the primary hard tube type endoscope, the semi-curved type endoscope to the fiber endoscope and the current electronic endoscope is also in a secondary leap. At present, the endoscope can obtain a color photo or a color television image by using LED illumination, and meanwhile, the image is not a common image of a tissue organ, but a microscopic image observed under a microscope, and tiny lesions are clear and distinguishable. According to the existing clinical experience, the smaller the volume of the miniature probe of the endoscope and the shorter the rigid section, the pain of the patient can be reduced to the greatest extent, so that the endoscope is always miniaturized. Current endoscopes have a large magnification resulting in a small field of view.

With the development of medical diagnosis in recent years, the narrow field of view of the conventional endoscope cannot meet the current requirements of medical diagnosis. At present, one design in the United kingdom and the United states realizes an ultra-large field of view, and two designs are commercialized, the two designs rely on the effect of greatly increasing the diameter of an incident beam so as to bring a large field of view and a large light flux, but the two designs cause the objective lens of the miniature probe of the endoscope to be very expensive and large, and the objective lens does not accord with the development trend of the endoscope.

SUMMERY OF THE UTILITY MODEL

The utility model provides a miniature endoscope of big visual field, under the unchangeable prerequisite of keeping incident beam diameter, the increase angle of vision reduces the volume of the miniature probe of endoscope, solves among the prior art and causes objective and the problem that miniature probe volume increases for realizing big visual field.

The scheme is basically as follows: the utility model provides a miniature endoscope of big visual field, includes miniature probe, miniature probe include the shell, with the fixed objective of shell and locate the scanner in the shell, objective is located outside the objective lens mirror body according to the back focal plane that the exciting light wavelength calculated, the scanner is located the back focal plane position department of objective.

Has the advantages that: this scheme is compared with objective (scan lens), the utility model discloses have ultrashort focal length, high numerical aperture, less angle of vision. The scheme has a larger field angle and an external back focal plane, and is unique because the scheme is greatly different from a common scanning lens and a common microscope objective. In use, when a single-axis scanner or a single dual-axis scanner is used, the single-axis scanner or the single dual-axis scanner is located in the back focal plane of the objective lens; when a set of two single axis scanners is used, the back focal plane of the objective lens is located in the middle of the set of two single axis scanners. Because the utility model discloses a back focal plane keeps away from the mirror body (usually for several millimeters far away), consequently has sufficient space installation scanner, and need not to set up scanning lens and sleeve lens (tube lens) between scanner and the objective in the same traditional laser scanning endoscope, the length of microscope scanning and formation of image light path is shortened greatly, the utility model is used for with the exciting light beam focus by the scanner reflection in the sample to collect the emitted light signal that excites in the sample, advance through the coupling of focusing lens and be used for transmitting the optic fibre of light signal or be used for detecting the photoelectric detector of light signal.

Further, the scanner adopts a dichroic mirror scanner, the dichroic mirror scanner comprises a driver and a plurality of dichroic mirrors, and the dichroic mirrors are used for reflecting laser and allowing nonlinear optical signals to pass through; the driver is used for changing the angle of the dichroic mirror according to the instruction, the driver comprises a plurality of mirror bodies for transmitting the nonlinear optical signals, and the dichroic mirror is fixed on the surface of the mirror bodies.

Compared with the traditional MEMS scanner in the prior art, the two-way scanner can meet the imaging quality on the premise of no scanning lens or no sleeve lens, reduces the number of lenses in the shell, reduces the volume of the miniature probe and greatly improves the imaging speed.

Further, the dichroic mirror comprises an ultrathin sheet, and a dichroic film is plated on the ultrathin sheet.

The dichroic mirror obtained in this way can be thinner and lighter, which is beneficial to further reducing the volume and weight of the miniature probe.

Further, the objective lens comprises a first lens, a second lens, a third lens, a fourth lens and a fifth lens, wherein emergent rays sequentially pass through the first lens, the second lens, the fourth lens and the fifth lens, the first lens is a concave-convex lens, the second lens is a double-convex lens, the third lens is a concave-convex lens, the fourth lens is a concave-convex lens, and the fifth lens is a double-convex lens. The objective lens in this combination may be such that the focal plane is located outside the lens body.

Further, the radii of curvature of an opposite image side surface S11 and an opposite object side surface S12 of the lens are-5.422 mm and-15.096 mm, respectively; the radii of curvature of the two opposite object side surfaces S21 and S22 of the lens are 40.057mm and-119.509 mm, respectively; the radii of curvature of the three opposite object side surface S31 and the opposite object side surface S32 of the lens are 18.574mm and 39.689mm, respectively; the curvature radii of the four opposite object side surfaces S41 and S42 of the lens are 6.873mm and 8.074mm respectively; the radii of curvature of the four opposite object side surfaces S51 and the opposite object side surface S52 of the lens are 103.816mm and-26.042 mm, respectively.

The surface farther from the scanning object than the image side surface, i.e., the lens, and the surface closer to the scanning object than the object side surface, i.e., the lens. The surface curvature of each lens is set according to the parameters, and the objective lens is relatively small in size on the premise of ensuring a large view field.

Further, the thickness of S11 is 14.307mm, the thickness of S12 is 0.2mm, the thickness of S21 is 1.5mm, the thickness of S22 is 0.2mm, the thickness of S31 is 1.674mm, the thickness of S32 is 0.2mm, the thickness of S41 is 6.083mm, the thickness of S42 is 0.75mm, the thickness of S51 is 6.083mm, and the thickness of S52 is 0.75 mm.

The lens is set according to the parameters, and the axial length of the objective lens is shorter on the premise of ensuring a large view field.

Further, the radius of S11 is 6mm, the radius of S12 is 14mm, the radius of S21 is 14mm, the radius of S22 is 14mm, the radius of S31 is 14mm, the radius of S32 is 14mm, the radius of S41 is 12mm, the radius of S42 is 6.6mm, the radius of S51 is 7.2mm, and the radius of S52 is 7.2 mm.

Thus, when the objective lens satisfies a large field of view, the cross-sectional area of the objective lens is small, which is composed of the radii of the respective surfaces.

Furthermore, the first lens, the second lens, the third lens, the fourth lens and the fifth lens are all made of optical glass or high molecular polymer or infrared imaging materials. Optical glass or high molecular polymers or infrared imaging materials are common materials for lenses in the art.

Further, the numerical aperture of the objective lens is greater than or equal to 0.7.

Further, the field angle of the objective lens is 15 degrees or more.

Drawings

Fig. 1 is a schematic structural diagram of the miniature probe of the present invention.

Fig. 2 is a schematic view of an optical structure of an objective lens according to an embodiment of the present invention.

Fig. 3 is a graph of field curvature and distortion of the excitation light wavelength according to an embodiment of the present invention.

Fig. 4 is a focal plane vignetting diagram of excitation light wavelength according to an embodiment of the present invention.

Fig. 5 is a schematic diagram of a scanner according to an embodiment of the present invention.

Detailed Description

The following is further detailed by way of specific embodiments:

reference numerals in the drawings of the specification include: the system comprises a first lens 1, a second lens 2, a third lens 3, a fourth lens 4, a fifth lens 5, a scanner 6, a laser input optical fiber 90, a laser output optical fiber 91, a driver 22, a dichroic mirror 33 and a miniature probe 50.

The examples are essentially as follows:

a miniature endoscope with a large visual field is shown in figure 1 and comprises a miniature probe 50, wherein the miniature probe 50 comprises a shell and an objective lens, the shell is a sealing structure made of high polymer materials, a scanner 6 and a plurality of lenses are arranged in the shell, the upper end of the shell is connected with a laser input optical fiber 90 and a laser output optical fiber 91, the objective lens is fixed at the lower end of the shell, namely the front aperture, and the scanner 6 is positioned above the objective lens. The scanner 6 is rotatably connected to the housing so that the scanner 6 can be angularly displaced for scanning. The laser emitted by the output optical fiber is reflected by the two-way reflector and then emitted from the objective lens to irradiate on human tissues.

As shown in fig. 2, the objective lens includes a first lens 1, a second lens 2, a third lens 3, a fourth lens 4, and a fifth lens 5, and the scanner 6 is located on a back focal plane of the objective lens calculated from the excitation light wavelength. Wherein, the first lens 1 is a convex-concave lens, the second lens 2 is a biconvex lens, the third lens 3 is a convex-concave lens, the fourth lens 4 is a convex-concave lens, and the fifth lens 5 is a biconvex lens.

Lens one 1 has an opposite-image-side surface S11 and an opposite-object-side surface S12, lens two 2 has an opposite-image-side surface S21 and an opposite-object-side surface S22, lens three 3 has an opposite-image-side surface S31 and an opposite-object-side surface S32, lens four 4 has an opposite-image-side surface S41 and an opposite-object-side surface S42, and lens five 5 has an opposite-image-side surface S51 and an opposite-object-side surface S52.

The materials of the first lens 1, the second lens 2, the third lens 3, the fourth lens 4 and the fifth lens 5 are optical glass or high molecular polymers or infrared imaging materials.

The data for each lens surface satisfies the following table:

wherein the excitation light wavelength is 920 nm and the emission light wavelength is 520 nm.

The numerical aperture of the objective lens is 0.7, the working distance is 1 mm, and the diameter of the field of view is 1.65 mm.

The embodiment is used for nonlinear optical imaging, so that the requirement on the offset is not high.

FIG. 3 shows the field curvature and distortion plot of the excitation light wavelength of this embodiment, and since this embodiment is used for in vivo biological tissue imaging, the requirement for distortion of the field curvature is not high.

Fig. 4 shows a focal plane vignetting diagram of the excitation light of the present embodiment, wherein the wavelength of the excitation light reaches a transmission efficiency of more than 0.5 at the maximum viewing angle.

As shown in fig. 5, the scanner 6 employs a dichroic mirror scanner, which includes a driver 22 and a plurality of dichroic mirrors 33, wherein the dichroic mirrors 33 are used for reflecting laser light and allowing nonlinear optical signals to pass through; the driver 22 is used for changing the angle of the dichroic mirror 33 according to the instruction, the driver 22 comprises a plurality of mirrors for transmitting the nonlinear optical signal, and the dichroic mirror 33 is fixed on the surface of the mirrors.

Dichroic mirror 33 comprises an ultrathin sheet coated with a dichroic film, and dichroic mirror 33 reflects laser light incident from laser light incident fiber 90 and transmits emitted light (e.g., fluorescence photons) excited by human tissue. Compared with the traditional MEMS scanner 6 in the prior art, the two-way scanner 6 can meet the imaging quality on the premise of no scanning lens or sleeve lens, reduce the number of lenses in the shell, reduce the volume of the miniature probe 50 and greatly improve the imaging speed.

The above are merely examples of the present invention, and common general knowledge of known specific structures and characteristics in the schemes is not described herein. It should be noted that, for those skilled in the art, without departing from the structure of the present invention, several modifications and improvements can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicability of the patent. The scope of the claims of the present application shall be determined by the contents of the claims, and the description of the embodiments and the like in the specification shall be used to explain the contents of the claims.

Claims

1. The utility model provides a miniature endoscope of big visual field, includes miniature probe, miniature probe include the shell, with the fixed objective of shell and locate the scanner in the shell, its characterized in that: the back focal plane calculated by the objective lens according to the wavelength of the exciting light is positioned outside the objective lens body, and the scanner is positioned at the back focal plane of the objective lens.

2. The large field of view miniature endoscope according to claim 1, characterized in that: the scanner adopts a dichroic mirror scanner, the dichroic mirror scanner comprises a driver and a plurality of dichroic mirrors, and the dichroic mirrors are used for reflecting laser and allowing nonlinear optical signals to pass through; the driver is used for changing the angle of the dichroic mirror according to the instruction, the driver comprises a plurality of mirror bodies for transmitting the nonlinear optical signals, and the dichroic mirror is fixed on the surface of the mirror bodies.

3. The large field of view miniature endoscope according to claim 2, characterized in that: the dichroic mirror comprises an ultrathin sheet, and a dichroic film is plated on the ultrathin sheet.

4. A large field of view miniature endoscope according to claim 3, characterized in that: the objective lens comprises a first lens, a second lens, a third lens, a fourth lens and a fifth lens, wherein emergent rays sequentially pass through the first lens, the second lens, the third lens, the fourth lens and the fifth lens, the first lens is a concave-convex lens, the second lens is a double-convex lens, the third lens is a concave-convex lens, the fourth lens is a concave-convex lens, and the fifth lens is a double-convex lens.

5. The large field of view miniature endoscope according to claim 4, characterized in that: the curvature radii of an opposite image side surface S11 and an opposite object side surface S12 of the lens are-5.422 mm and-15.096 mm, respectively; the radii of curvature of the two opposite object side surfaces S21 and S22 of the lens are 40.057mm and-119.509 mm, respectively; the radii of curvature of the three opposite object side surface S31 and the opposite object side surface S32 of the lens are 18.574mm and 39.689mm, respectively; the curvature radii of the four opposite object side surfaces S41 and S42 of the lens are 6.873mm and 8.074mm respectively; the radii of curvature of the four opposite object side surfaces S51 and the opposite object side surface S52 of the lens are 103.816mm and-26.042 mm, respectively.

6. The large field of view miniature endoscope according to claim 5, characterized in that: the thickness of S11 is 14.307mm, the thickness of S12 is 0.2mm, the thickness of S21 is 1.5mm, the thickness of S22 is 0.2mm, the thickness of S31 is 1.674mm, the thickness of S32 is 0.2mm, the thickness of S41 is 6.083mm, the thickness of S42 is 0.75mm, the thickness of S51 is 6.083mm, and the thickness of S52 is 0.75 mm.

7. The large field of view miniature endoscope according to claim 6, characterized in that: the radius of S11 is 6mm, the radius of S12 is 14mm, the radius of S21 is 14mm, the radius of S22 is 14mm, the radius of S31 is 14mm, the radius of S32 is 14mm, the radius of S41 is 12mm, the radius of S42 is 6.6mm, the radius of S51 is 7.2mm, and the radius of S52 is 7.2 mm.

8. A large field of view miniature endoscope according to any of claims 4-7, characterized in that: the first lens, the second lens, the third lens, the fourth lens and the fifth lens are all made of optical glass or high molecular polymer or infrared imaging materials.

9. The large field of view miniature endoscope according to claim 8, characterized in that: the numerical aperture of the objective lens is greater than or equal to 0.7.

10. The large field of view miniature endoscope according to claim 8, characterized in that: the field angle of the objective lens is equal to or larger than 15 degrees.