JPH1043128A - Endoscope optical system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the fogging of an endoscope optical system even if the system is inserted into the celom, etc., by irradiating the outside surface of a lens or cover on the closest to objects side with electron beams, thereby subjecting the surface to a fogging preventive treatment to increase a hydrophilic property. SOLUTION: A CCD unit 2 is arranged on the imaging surface of the objective lens 1 at the front end of the endoscope and the endoscope is provided with a light guide 3 for illuminating the observation surface and a lens 4 for illumination for widening the illumination light from the light guide 3. The endoscope is provided with an air and water feed nozzle 5 for blowing water and sending air when the front surface of the objective lens 1 is contaminated. The first surface (outside surface) and second surface (inside surface) of the front end lens 11 of the objective lens 1 are subjected to the hydrophilic treatment by irradiating these surfaces with the electron beams. The hydrophilic treatment is otherwise executed by irradiating the surfaces with plasma in place of the execution of the hydrophilic treatment by the irradiation with the electron beams.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an endoscope, and more particularly to an endoscope optical system that prevents fogging due to the attachment of water droplets.

[0002]

2. Description of the Related Art An endoscope typified by a rigid endoscope or a flexible endoscope for observing the inside by inserting it into a body cavity or the like and performing a treatment or the like is particularly difficult for medical endoscopes. There is a problem that the generated water vapor fogs the surface of the optical system. Conventionally, a water-repellent coat is applied to the surface of an observation window objective lens or an illumination window lens in order to prevent a cleaning solution or the like from adhering to an observation window or an illumination window lens inserted into a body cavity or the like. Is known (JP-A-2-129613).
issue).

[0003]

However, particularly for medical endoscopes, the tip of the insertion portion is immersed in a disinfecting solution, exposed to a disinfecting gas, or placed in high-temperature steam for disinfection and sterilization. Since such a water-repellent coat must be removed from the lens because it has to go through a severe use environment such as sterilization (autoclave) and plasma sterilization, it cannot always be used continuously for endoscopes. Was.

On the other hand, although not for endoscopes, it has been proposed to apply a hydrophilic coating to prevent fogging of eyeglasses and the like. However, when this is applied to an endoscope, it is similar to a water-repellent coat. In addition, due to severe use environment such as disinfection and sterilization, there is a high possibility that the lens will be peeled off from the lens, and it is not always suitable for an endoscope at present.

The present invention has been made in view of such problems of the prior art, and an object of the present invention is to provide a surface of an observation window or an illumination window with hydrophilicity based on a novel principle so that a body cavity can be obtained. It is an object of the present invention to provide an endoscope optical system which does not fog even when inserted into the optical system.

[0006]

An endoscope optical system according to the present invention, which achieves the above object, comprises an objective lens or an illumination lens, which is disposed at the tip of an insertion portion of the endoscope, which is the most object of the lens. The outer surface of the lens or cover glass on the side is subjected to an anti-fogging treatment for increasing hydrophilicity by irradiating an electron beam.

In this case, the fogging prevention processing may be performed before assembling the endoscope optical system, may be performed after assembling the endoscope optical system, or may be performed before using the endoscope. Good.

Another endoscope optical system according to the present invention comprises an endoscope provided with an eyepiece and a TV camera connected to the observation side of the eyepiece, and is provided on the most observation side of the endoscope. At least one of an outer surface of a lens or a cover glass and an outer surface of a lens or a cover glass closest to the object of the TV camera is subjected to an anti-fog treatment for increasing hydrophilicity by irradiating an electron beam. is there.

Also in this case, the fogging prevention processing is performed before assembling the endoscope optical system, or is performed after assembling the endoscope optical system or before using the endoscope. Is also good.

In the present invention, the fogging prevention treatment may be performed by irradiating a plasma instead of irradiating an electron beam.

In the present invention, the outermost surface of the lens or cover glass closest to the object side of at least one of the objective lens and the illumination lens, or the outermost surface of the lens or cover glass closest to the endoscope, a TV camera At least one of the lens on the most object side or the outer surface of the cover glass has been subjected to an anti-fogging treatment that increases hydrophilicity by irradiating an electron beam. The optical system is not fogged by the dew, and a clear image can be safely observed.
In addition, the fogging prevention effect does not deteriorate even in severe use environments such as disinfection and sterilization.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The basic principle of the present invention is to irradiate the surface of an inorganic material such as an optical glass or an optical crystal with an electron beam to reduce the contact angle with water on the surface and improve the wettability. This is the fact that the hydrophilicity is increased and fogging due to water vapor can be prevented.

As the sample glass, SiO ₂ : 70-73
w%, Al ₂ O ₃ : 1.0 to 1.8 w%, Fe ₂ O ₃ :
0.08 to 0.14 w%, CaO: 7 to 12 w%, Mg
Using a glass having a composition of O: 1.0 to 4.5 w% and RaO: 13 to 15 w%, electron beam irradiation was performed on the surface of the sample glass under the following conditions. Acceleration potential difference: 170 kV Electron beam current: 4 mA Conveyor speed: 5.57 m / s Atmosphere: Nitrogen at atmospheric pressure Oxygen concentration: less than 400 ppm ) After spraying on the sample, a method of measuring the time during which the surface of the sample is cloudy was measured.

As a result, the relationship between the fogging time and the amount of electron beam irradiation was as shown in FIG. From this figure, it was found that in the case of this sample, the fogging time decreases as the irradiation dose increases, and that when the dose exceeds 45 Mrad, the fog clearing time becomes 1 second or less, and the fogging prevention effect is saturated. . Then, it was found that the reason was that the contact angle of the surface with water was reduced, the wettability was improved, and the hydrophilicity was increased. Note that the sample does not deteriorate at such an amount of electron beam irradiation.

The same effect of improving hydrophilicity and preventing fogging was confirmed for synthetic sapphire (Al ₂ O ₃ crystal).

As described above, the physical and chemical reasons for irradiating the surface of an inorganic material such as an optical glass or an optical crystal with an electron beam to increase the hydrophilicity and prevent fogging are not clear at present. It is known that the present invention can be applied to other inorganic materials such as optical glass and optical crystal. It has also been found that plasma irradiation may be used instead of electron beam irradiation.

The present invention utilizes such a basic principle,
An anti-fog treatment is performed by irradiating an electron beam or plasma to a lens of an observation window or an illumination window of an endoscope to increase hydrophilicity. Hereinafter, some embodiments will be described.

FIG. 1 is a diagram showing a cross section of the distal end of an insertion portion of an electronic scope which is a kind of a flexible endoscope. The schematic configuration of the distal end portion of the endoscope includes an objective lens 1 for observing the inserted interior. The front surface of the CCD unit 2 disposed on the image forming surface, the light guide 3 for illuminating the observation surface, the illumination lens 4 for expanding the illumination light from the light guide 3, and the front surface of the objective lens 1 are dirty. An air supply / water supply nozzle 5 for blowing water or sending air sometimes.

In such a configuration, when the front surface of the objective lens 1 becomes dirty, water is supplied from the air / water supply nozzle 5 to spray water and the front surface is washed, but if there is a difference between the body temperature and the water temperature, In addition, the front surface of the objective lens 1 becomes clouded by water vapor in the body.

Therefore, in the present invention, the objective lens 1
Surface (outer surface) and second surface (inner surface) of the front end lens 11
Is irradiated with an electron beam to perform a hydrophilic treatment so that a fogging prevention effect can be obtained.

For the electron beam irradiation for such hydrophilic treatment, for example, an electron beam irradiation apparatus having a cross section shown in FIG. 2 (ELECTROCURTAIN PROCESSOR manufactured by Iwasaki Electric Co., Ltd.) is used. This device accelerates thermoelectrons emitted from a linear filament 7 disposed in a vacuum chamber 6 by a high voltage applied between the linear filament 7 and an anode in a lower portion of the vacuum chamber 6, and forms a curtain into a vacuum chamber 6. The irradiation electron beam 9 is obtained through the partitioning titanium foil 8,
The surface of the sample S (tip lens 11) placed on the conveyor 10 can be uniformly irradiated with a predetermined amount of electron beam without causing irradiation damage.

In the above, not only the first surface (outer surface) but also the inner second surface of the tip lens 11 of the objective lens 1 is subjected to the hydrophilic treatment by irradiating the electron beam with the surface around the tip lens 11. It is possible that water vapor may enter the inner side beyond the above, so that the inside second surface is also subjected to hydrophilic treatment for safety considerations, and it is not always necessary to perform the treatment.

In the embodiment shown in FIG. 1, the first surface (outer surface) and the second surface (inner surface) of the tip lens 41 of the illumination lens 4 are also irradiated with the same electron beam to perform hydrophilic treatment. In this case, it is possible to prevent a decrease in the amount of illumination light due to clouding of the illumination lens 4 due to water vapor, which is more preferable.

FIG. 3 is a cross-sectional view of the distal end of an insertion portion of a side-view type fiberscope which is another type of flexible endoscope. An objective lens 1 for observation and an image guide (optical fiber bundle) 12 having an incident end face arranged on an image forming surface thereof;
A light guide 3 for illuminating the observation surface, an illumination lens 4 for spreading illumination light from the light guide 3,
When the front of the objective lens 1 becomes dirty,
And an air / water nozzle 5 for sending air. In this example, the tip lens 11 of the objective lens 1 also serves as a reflection prism for directing the optical path to the side, and the illumination lens 4 is composed of one concave lens.

In this embodiment, as in the embodiment shown in FIG. 1, the first surface (outer surface) of the front end lens 11 of the objective lens 1 is also provided.
In addition, the second surface (prism incident surface) is irradiated with an electron beam using an electron beam irradiation apparatus as shown in FIG. 2 to perform a hydrophilic treatment so that a fogging prevention effect can be obtained. In addition, it is more desirable that both surfaces of the illumination lens 4 are similarly irradiated with an electron beam to perform hydrophilic treatment.

Next, an embodiment in which the present invention is applied to a rigid endoscope will be described. FIG. 4A is an overall view of a rigid endoscope, and FIG.
4B is a cross-sectional view of the eyepiece, and FIG. 4C is a cross-sectional view of the distal end of the insertion portion. The schematic configuration of this rigid endoscope is composed of an eyepiece 15 and an insertion part 16 which are integrally and linearly continuous, and an objective lens 21 is provided at the tip of the insertion part 16 with an eyepiece 1.
An eyepiece 22 is mounted in the eyepiece 17 of No. 5, and an image transmission lens system 23 is disposed between the objective lens 21 and the eyepiece 22. Further, for illumination, a light guide 24 is arranged from the light guide cable connector 18 provided on the side of the eyepiece 15 to the tip of the insertion portion 16, and the illumination tip is exposed in the same direction as the objective lens 21. ing. An objective cover glass 25 made of sapphire is arranged on the front surface of the objective lens 21, and an eyepiece cover glass 26 is arranged on the observation side of the eyepiece 22.

Also in this embodiment, when the insertion portion 16 of the endoscope is inserted into the abdominal cavity during endoscopic surgery, if there is a difference between the body temperature and the room temperature, the water vapor in the body causes the objective cover to be covered. The outer surface of the glass 25 becomes cloudy. Therefore, similarly to the above-described embodiment, the outer surface of the objective cover glass 25 is irradiated with an electron beam using an electron beam irradiation device as shown in FIG. 2 to perform a hydrophilic treatment so that a fogging prevention effect can be obtained. is there.

Further, based on the embodiment shown in FIG. 5, it is more preferable that the outer surface of the eyepiece cover glass 26 is similarly irradiated with an electron beam to perform hydrophilic treatment.

Next, an embodiment in which a TV camera is connected to a rigid endoscope as shown in FIG. 4 will be described. FIG. 5 is a diagram showing the entire configuration of the adapter 3 having the imaging lens 31 built in the eyepiece 17 of the rigid endoscope eyepiece 15 shown in FIG.
0 is connected to one end, and the other end of the adapter 30 is connected to the camera head 50. In the camera head 50,
A CCD 51 is arranged at a position corresponding to an image forming surface of the imaging lens 31 in the adapter 30 via a filter 52 including a low-pass filter and an infrared cut filter. A signal from the CCD 51 is transmitted to a control unit via a signal cable 54. 55. The control unit 55 includes a T (not shown).
A V display device is connected, and an observation image formed by a rigid endoscope formed on the imaging surface of the CCD 51 by the imaging lens 31 can be enlarged and displayed.

The connection between the rigid endoscope, the adapter 30 and the camera head 50 is made before the use of the endoscope in the operating room. Dew may form on the cover glass and become cloudy, and an observed image may not be clearly displayed. Therefore, according to the present invention, the eyepiece 22 in the eyepiece 17 of the rigid endoscope is used.
Of the cover glass 26 provided on the observation side, the cover glass 33 provided on the entrance side and the exit side of the imaging lens 31 in the adapter 30, and the outer surface of the cover glass 53 provided on the entrance side of the camera head 50. Similarly to the example, an electron beam is irradiated by using an electron beam irradiation apparatus as shown in FIG. 2 to perform a hydrophilic treatment so that a fogging prevention effect can be obtained.

In each of the above embodiments, the hydrophilic treatment for irradiating the electron beams of the various optical systems of the endoscope is performed before assembling the endoscope or the like. The electron beam may be irradiated to the outer surface of the endoscope optical system after assembly or before use of the endoscope. In particular, it is preferable that the hydrophilic treatment be performed by irradiating the endoscope with an electron beam before use, because the endoscope insertion portion can be disinfected and sterilized at the same time.

Instead of performing the hydrophilic treatment by irradiating an electron beam using an electron beam irradiation apparatus as shown in FIG. 2, a hydrophilic treatment may be performed by irradiating a plasma using a known plasma irradiation apparatus. Even so, the same effect can be obtained.

It has not yet been confirmed whether or not the fogging prevention effect is maintained over a long period of time, such as the life cycle of an endoscope as a product. By irradiating the device with an electron beam or the like, the fogging prevention effect can be restored without replacing parts.

Further, the optical components constituting the outer surface of the product which is directly placed in the environment during disinfection and sterilization are required to have extremely high durability. The above-mentioned optical crystal such as synthetic sapphire has high optical stability as compared with ordinary optical glass, and thus is suitable as such an optical component. In the above embodiment, the objective cover glass of FIG. 4 is made of sapphire. However, in other embodiments, the objective lens, the lens closest to the object of the illumination lens, or the cover glass, the cover of the eyepiece, etc. It is desirable that the parts that are exposed on the outer surface, such as glass and the cover glass of the adapter, be made of sapphire.

Although the endoscope optical system of the present invention has been described based on several embodiments, the present invention is not limited to these embodiments, and various modifications can be made.

[0036]

As is apparent from the above description, according to the endoscope optical system of the present invention, the outermost surface of the most object side lens or cover glass of at least one of the objective lens and the illumination lens, or At least one of the outermost surface of the lens or the cover glass of the endoscope and the outermost surface of the lens of the TV camera or the outer surface of the cover glass is subjected to an anti-fog treatment to increase hydrophilicity by irradiating an electron beam. Therefore, even in an environment in which the endoscope is used, the optical system does not fog due to condensation of water vapor or the like in the body, and a clear image can be safely observed. In addition, the fogging prevention effect does not deteriorate even in severe use environments such as disinfection and sterilization.

[Brief description of the drawings]

FIG. 1 is a sectional view of a distal end of an insertion portion of an electronic scope according to one embodiment of the present invention.

FIG. 2 is a cross-sectional view of an example of an electron beam irradiation device for hydrophilic treatment.

FIG. 3 is a cross-sectional view of a distal end of an insertion portion of a side-view type fiberscope according to another embodiment of the present invention.

FIG. 4 is an overall view of a rigid endoscope according to yet another embodiment of the present invention, a sectional view of an eyepiece, and a sectional view of a distal end of an insertion portion.

FIG. 5 is a diagram showing an entire configuration of an embodiment when a TV camera is connected to a rigid endoscope.

FIG. 6 is a graph showing a relationship between a cloudy time and an electron beam irradiation amount.
It is a figure of an example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Objective lens 2 ... CCD unit 3 ... Light guide 4 ... Illumination lens 5 ... Air supply / water supply nozzle 6 ... Vacuum chamber 7 ... Linear filament 8 ... Titanium foil 9 ... Irradiation electron beam 10 ... Conveyor 11 ... Tip lens 12 ... Image guide 15 ... Eyepiece 16 ... Insertion part 17 ... Eyepiece 18 ... Light guide cable connector 21 ... Objective lens 22 ... Eyepiece 23 ... Image transmission lens system 24 ... Light guide 25 ... Objective cover glass 26 ... Eyepiece cover glass 31 ... Imaging lens 30 ... Adapter 33, 53 ... Cover glass 41 ... Tip lens 50 ... Camera head 51 ... CCD 52 ... Filter 54 ... Signal cable 55 ... Control unit S ... Sample

Claims (7)

[Claims] An electron beam is applied to an outermost surface of a cover glass or an object-side lens of at least one of an objective lens and an illumination lens disposed at a distal end of an insertion portion of an endoscope. An endoscope optical system characterized by having been subjected to a fogging prevention process that increases the fog. 2. The endoscope optical system according to claim 1, wherein the fogging prevention processing is performed before assembling the endoscope optical system. 3. The endoscope optical system according to claim 1, wherein the fogging prevention processing is performed after assembling the endoscope optical system or before using the endoscope. 4. An endoscope provided with an eyepiece and a TV camera connected to an observation side of the eyepiece, wherein an outermost lens of the endoscope or an outer surface of a cover glass, and a TV camera An endoscope optical system, wherein at least one of a lens closest to an object and an outer surface of a cover glass is subjected to an anti-fog treatment for increasing hydrophilicity by irradiating an electron beam. 5. The endoscope optical system according to claim 4, wherein the fogging prevention processing is performed before assembling the endoscope optical system. 6. The endoscope optical system according to claim 4, wherein the fogging prevention processing is performed after assembling the endoscope optical system or before using the endoscope. 7. The endoscope according to claim 1, wherein the fogging prevention processing is performed by irradiating a plasma instead of irradiating an electron beam. Mirror optics.