JPH068910U - Optical fiber laser device - Google Patents

Abstract

(57) [Abstract] [Purpose] It is an object of the present invention to provide an optical fiber laser device in which the contamination of an objective lens can be easily removed and the cost can be reduced as compared with a conventional product. A ball lens 31 is installed at the tip of an optical fiber 1 that guides a laser beam, and the objective side of the ball lens 31 is projected outside the base 2 in which the ball lens 31 is housed.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a laser device, and more particularly to an optical fiber laser device used in a pulse laser device.

[0002]

[Prior art]

 As a treatment method inside the body, there is a treatment method using laser light called photodynamic therapy. This treatment method uses a laser device, in particular, a pulse laser device to emit light energy compressed in a pulsed state inside the body through an optical fiber to perform treatment. The part becomes a shock wave and the bodily fluid is scattered by the shock wave, and the evaporated bodily fluid firmly adheres and bonds to the lens inside the optical fiber tip base, contaminating the lens surface, and it is very difficult to remove the adhered bodily fluid due to the structure. Is a problem with. FIG. 1 shows the structure of the tip of a conventional optical fiber laser device used for laser treatment such as photodynamic therapy. 1 is an optical fiber, 2 is a lens housing lens, and 3 is a cylindrical GRIN lens. Reference numeral 4 denotes a claw for preventing the GRIN lens from falling off, which is a part of the base 2. In addition, in laser treatment methods such as photodynamic therapy, it is often necessary to uniformly irradiate the affected area inside the body with laser light.In this case, install an appropriate lens at the tip of the optical fiber. It is necessary to use a cylindrical GRIN lens 3 manufactured by Nippon Sheet Glass Co., Ltd., which is known as a SELFOC lens in the form of being housed in a base 2 at the tip of an optical fiber 1 as shown in FIG. Has been. However, in this conventional structure, since the nail 4 for preventing the lens 3 from falling off is present, it is not possible to wipe off the burning contamination on the lens surface, and in fact, immediately after contamination by a method such as ultrasonic cleaning. Almost no contaminants could be removed even after washing.

[0003]

[Problems to be solved by the device]

 The first problem to be solved by the present invention is to reduce the contamination at the tip of an optical fiber laser device used for photodynamic therapy treatment using a pulsed laser, and to easily remove the contamination when it occurs. Is to provide the structure. The second problem is that an inexpensive lens is used instead of an expensive GRIN lens, the same optical effect is obtained, and the light irradiation spot size can be adjusted without changing the parts. It is to provide a high structure.

[0004]

[Means for Solving the Problems]

 In order to solve the above problems, the present invention has a structure in which a spherical lens is installed at the tip of an optical fiber that guides a laser beam, and the objective side of the spherical lens is projected outside the base housing the spherical lens. It is a thing.

[0005]

[Action]

 With the above-mentioned structure, unlike the conventional case, no concave portion is formed between the pawl and the spherical lens, and since the concave portion is projected from the base, it is easy to remove the contamination. Also, by adjusting the mutual relationship between the focal point position of the spherical lens and the end position of the optical fiber, there is an advantage that the light irradiation spot size can be adjusted without changing the parts, and the spherical lens can be obtained at a lower cost than the conventional GRIN lens. Combined with what is done, the economic effect is high.

[0006]

【Example】

 FIG. 2 shows a first embodiment of the present invention used for laser treatment such as photodynamic therapy, in which 1 is an optical fiber, 2 is a base for holding a ball lens 31, 4 is a nail for holding the ball lens, and 6 Is a lens presser from the inside, and in this way, the objective side 5 of the spherical lens 31 is projected, and the wiping can be easily performed. FIG. 3 shows a second embodiment of the present invention, in which an internal base 7 screwed into the base 2 is provided, and the optical fiber 1 screwed into the internal base 7 is rotationally adjusted to adjust the focus of the spherical lens 31. It is configured so that the relative position between the position and the end face of the optical fiber 1 can be adjusted to adjust the emission pattern of the laser light and the light irradiation spot size. In this embodiment, a BK-7 optical glass having a diameter of 1.0 mm with a refractive index of 1,516 is used as the spherical lens 31, and the optical fiber 1 is HN-S-FB400, core sold by Toray Industries, Inc. A diameter of 400 μm was used. It was confirmed that the surface of the spherical lens 31 on the object side protrudes from the base 2, and that it can be easily wiped with absorbent cotton impregnated with a solvent and that the contamination can be sufficiently removed. Further, FIG. 4A shows a far field pattern manufactured by Hamamatsu Photonics Co., Ltd. at a position 65 mm from the tip when an excimer die laser having a wavelength of 628 nm and 6 mj / pulse is incident on the optical fiber laser device of the second embodiment. It is a laser emission pattern figure which installed the detector of measuring device FFP-200, and was measured. Further, FIG. 4B is a laser beam emission pattern of an optical fiber laser device using a conventional GRIN lens measured under the same conditions, and a comparison of FIG. 4A and FIG. It is clear that the fiber optic laser guide has a good laser light emission pattern. FIG. 5 shows a third embodiment of the present invention, which is provided with a pollution prevention structure using a fluid such as air. That is, in the third embodiment shown in FIG. 5, the flexible tube 10 is covered with the separators 8 and 9 on the outer side of the optical fiber laser device A having the same structure as the embodiment shown in FIG. It is a thing. In the embodiment, a flexible tube 10 made of Teflon known as Teflon (registered trademark), a flexible tube made of ethylene polymer and having an inner diameter of 1.3 mm and an outer diameter of 1.7 mm is used. A suitable number of 8a were provided, the separator 9 was made of polypropylene plastic, and the fluid inlet 9a was formed. From this fluid inlet 9a, clean air was introduced at a rate of 50 ml / min, an excimer dye laser of 628 nm wavelength and 6 mj / pulse was incident on the optical fiber 1, and the model was placed close to the live pig liver. As a result of conducting experiments, the contamination of the spherical lens surface by the tissue fluid was considerably smaller than that in the case where no air was blown, and the effect was recognized. An optical fiber laser device for photodynamic therapy treatment or the like is often used to perform treatment while inserting it through the cannon hole of an endoscope and performing observation with the endoscope. It is convenient that the separator 9 which is a mouthpiece that allows the fluid to pass through is close to the mouthpiece 11 that makes the laser light incident on the optical fiber portion. In practice, the mouthpiece 11 that makes the laser light incident on the optical fiber portion is used. It is preferable that the separator 9 and the separator 9 are integrated. Air, water, and other chemically inert fluids flowing out from around the tip spherical lens of the optical fiber laser device A through the gap between the flexible tube 10 and the optical fiber 1 are projected to the outside. Contamination of the ball lens 31 by body fluid that flows over the surface of the ball lens 31 and is scattered or evaporated by laser irradiation is significantly prevented. Since it is better to pass the fluid during the laser irradiation treatment, a valve for adjusting the fluid flow rate is installed. In the above-described embodiments, only the case where the spherical lens is used is illustrated, but even if a general convex lens including an aspherical lens is used in place of the spherical lens, it is possible to obtain the one having the same action and effect. It is self-explanatory.

[0006]

[Effect of device]

 According to the present invention, it is possible to easily remove the contamination adhering to the objective lens, and to provide an optical fiber laser device in which the objective lens is less likely to be contaminated.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a conventional optical fiber laser device.

FIG. 2 is a sectional view of a first embodiment of the present invention.

FIG. 3 is a sectional view of a second embodiment of the present invention.

FIG. 4 is a laser light emission pattern diagram of the present invention and the conventional optical fiber laser device.

FIG. 5 is a sectional view of a third embodiment of the present invention.

[Explanation of symbols]

 1 Optical Fiber 2 Base 3 GRIN Lens 4 Claw 5 Object Side of Ball Lens 6 Lens Hold 7 Internal Base 8, 9 Separator 10 Flexible Tube 11 Base 31 Ball Lens

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tatsu Hirano 1126 No. 1126, Ichinomachi, Hamamatsu-shi, Shizuoka Prefecture (72) Inventor Masami Osawa 6767, Tamagawa Village, Hiki Group, Saitama Prefecture

Claims (2)

[Scope of utility model registration request] 1. An optical fiber laser device, characterized in that a spherical lens is installed at the tip of an optical fiber for guiding a laser beam, and the objective side of the spherical lens is projected to the outside of a base housing the spherical lens. . 2. The optical fiber laser device according to claim 1 is covered with a flexible tube via a separator, and a fluid passage is formed between the flexible tube and the optical fiber laser device. Optical fiber laser device.