JPH0984803A - Laser treatment apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a laser treatment apparatus enabling selective irradiation by arbitrarily changing the shape of the mask set to an irradiation optical system on the basis of the modified image of the image of the lesion part on the imaged surface of the body or body cavity. SOLUTION: The laser beam emitted from a laser oscillator 10 is expanded by a beam expander to be collimated by a collimate lens 16 to reach the surface of a lesion part 22 by an irradiation optical system 32. The laser beam transmitted through the shape changeable mask 18 arranged to the irradiation optical system 31 is condensed to the surface of the lesion part 22 by a condensing lens 20 to perform laser treatment matched with the shape of the mask 18. At this time, the reflected beam from the surface of the lesion part 22 is taken out of the irradiation optical system 32 by a half mirror 24 to be guided to a television camera 26. Herein, the shape of the shape changeable mask 18 is altered and the adjustment of a light cut-off region is performed to control the laser treatment shape on the surface of the lesion part 22.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser treatment apparatus for performing laser treatment by irradiating a lesion on a body surface or a body cavity with laser light through a mask.

[0002]

2. Description of the Related Art Conventionally, lasers have been extensively applied to the treatment of biological tissues by utilizing the excellent optical properties of laser such as monochromaticity, directivity, convergence, and high brightness.
Treatments such as blood coagulation and tissue coagulation are performed. In these laser treatments, an appropriate device has been selected and used depending on the wavelength and energy density of the laser to be irradiated, the optical characteristics of the living body tissue to be irradiated, and the type of treatment. However, it is difficult to control the laser irradiation site using any of the devices, and in order to irradiate only the lesion and not to affect the surrounding normal tissue, the laser light is focused and It was necessary not to expose the normal tissue to the laser. As a result, the surgeon had to exercise considerable care and effort.
When irradiating a relatively large area of living tissue without extremely narrowing the laser beam diameter, such as in the case of coagulation of tissue, laser irradiation may occur even in partially existing normal tissue. It was In order to avoid this, it was necessary to perform laser irradiation so as to leave normal tissue by dividing it into a plurality of parts.

[0003]

SUMMARY OF THE INVENTION Therefore, the present invention has been made in view of the above-mentioned problems, and a shape of a mask set in an irradiation optical system of a laser treatment apparatus is imaged, and a lesion on a body surface or a body cavity is imaged. It is an object of the present invention to provide a laser treatment apparatus capable of performing selective irradiation by arbitrarily changing a modulated image of an image.

[0004]

In order to solve the above-mentioned problems and to achieve the object, a laser treatment apparatus according to the present invention is a laser light source for irradiating a laser beam and focusing the laser beam on a lesion. An irradiation optical system, an imaging optical system for extracting an image of the lesion area, a camera for imaging reflected light reflected by the surface of the lesion area taken out by the imaging optical system, and provided in the irradiation optical system. A shape variable mask that changes the irradiation shape of the laser light onto the lesion surface, and a control device that controls the irradiation shape changing operation of the laser light by the shape variable mask based on an image captured by the camera. It is characterized by having and.

Further, in the laser treatment apparatus according to the present invention, the shape variable mask is a mask for changing a transmission shape of the laser light by using a liquid crystal.

Further, in the laser treatment apparatus according to the present invention, the variable shape mask is a mask for changing the transmission shape of the laser light by using fine ceramics.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a diagram showing the basic configuration of a laser treatment apparatus according to one embodiment.

In FIG. 1, a laser treatment apparatus 50 includes a laser oscillator 10 that oscillates a laser beam and a laser oscillator 1.
The beam expander 12 made of a convex lens for expanding the laser light emitted from 0, the spatial filter 14 for removing scattered light of the light emitted from the beam expander 12, and the beam expander 12 are expanded. A collimator lens 16 for returning the laser light to parallel light, and a variable shape mask 18 for shaping the shape of the collimated laser light into a desired shape necessary for treating the lesion 22.
And a condenser lens 20 for condensing the laser light that has passed through the variable shape mask 18. Further, a half mirror 24 for guiding the laser light reflected on the surface of the lesion 22 to the television camera 26 is provided between the variable shape mask 18 and the condenser lens 20. A control device 28 is connected to the television camera 26, and controls the variable shape mask 18 based on an image captured by the television camera 26. Further, a television monitor 30 is connected to the control device 28 so that the operator can observe the video imaged by the television camera 26.

The laser treatment apparatus constructed as described above is
It works as follows.

That is, the laser light emitted from the laser oscillator 10 is expanded by the beam expander 12, collimated by the collimator lens 16, and then reaches the surface of the lesion 22 by the irradiation optical system 32. Irradiation optical system 32
The laser beam transmitted through the shape-variable mask 18 installed at is focused on the surface of the lesion 22 by the condenser lens 20 to perform laser treatment according to the shape of the mask 18. At this time, the half mirror 24 takes out the reflected light from the surface of the lesion 22 from the irradiation optical system 32 and guides it to the television camera 26 so that the state of the surface of the lesion 22 can be observed. The image of the surface of the lesioned part 22 captured by the television camera 26 is input to the variable shape mask 18 as a modulated image after arithmetic processing by the control device 28. Thereby, the mask shape of the variable shape mask 18 is changed, the light-shielding portion is adjusted, and the laser treatment shape on the surface of the lesion 22 is controlled. That is, where the image is taken by the TV camera 26,
When the surface shape of the lesioned part 22 and the irradiation shape of the laser beam on the surface are not suitable for the shape to be treated on the lesioned part 22, the light transmission state of the variable shape mask 18 is changed to change the irradiation shape of the laser beam and the irradiation shape. The irradiation intensity is controlled to be suitable for treatment. At this time, by connecting to the television monitor 30, the image of the surface of the lesion 22 and the modulated image input to the variable shape mask 18 are observed. Mask 18
By inputting the modulation image of the lesion area 22 into the lesion area continuously or stepwise, effective treatment can be performed even when the shape of the lesion area changes with laser irradiation. The position, size and shape of each constituent member are arbitrary as long as they do not violate the gist of the present invention. Further, in the laser treatment apparatus according to the present invention, the wavelength of the laser used for oscillation and treatment is arbitrary, and the laser irradiation optical system and the imaging optical system do not necessarily have the same wavelength. Further, the observation of the lesion in the imaging system is not limited to visible light, and excitation light or the like emitted by the tissue of the lesion may be used as the position detecting means.

Further, an arm-shaped radiating portion in which a reflecting mirror 80 and a hollow tube 81 as shown in FIG. 2, a joint portion 82 and a condenser lens 83 are combined, an optical fiber as shown in FIG. 3, a hollow waveguide, The use of a flexible tubular radiating portion composed of a light guide member 84 such as a thin film waveguide and a condenser lens 85 also makes it possible to treat a lesion in a body cavity. Next, FIG.
FIG. 5 shows an example of the configuration of the variable shape mask 18 capable of changing the shape of the laser light shielding portion by inputting a modulation image.

As shown in FIG. 4, between the pair of transparent electrodes 40 and the pair of polarizing plates 42 whose polarization azimuth angles are orthogonal to each other, a light-transmissive ferroelectric fine film capable of changing the polarization characteristic of transmitted light. Ceramics such as PLZT [(Pb,
La) (Zr, Ti) O3] or the TN liquid crystal 44 is sandwiched to form the optical element 46. This optical element 46
Form one pixel of the variable shape mask 18. That is,
The optical elements 46 are arranged in a matrix as shown in FIG. 5, and the modulated image of the image of the surface of the workpiece 22 is input to each optical element 46 to control the laser transmission position and the light shielding position and the transmission ratio. And the variable shape mask 18 is formed. The position, size, and shape of the main body of the variable shape mask and each component are arbitrary as long as they do not violate the gist of the present invention.

In addition to the optical element for controlling the transmitted light by using the polarized light as in the above embodiment, the variable shape mask may be constructed by using an optical element utilizing the transmission and scattering characteristics. As shown in FIG. 6, a medium 62 in which a medium 60 such as a liquid crystal having a refractive index anisotropy is appropriately dispersed is sandwiched between two transparent electrodes 64, and the transmission and scattering of irradiated light is controlled by an electric field. The elements are arranged in a matrix. A condenser lens 66, an aperture 68, and a lens 70 for collimating the light passing through the aperture 68 again are arranged behind this matrix. Then, by inputting the modulated image of the image of the surface of the workpiece 22 to each of the above-mentioned optical elements, the shape variable mask is obtained. The position, size, and shape of the main body of the variable shape mask and each component are arbitrary as long as they do not violate the gist of the present invention.

[0015]

As described above, according to the present invention,
By capturing the image of the lesion area from the imaging optical system and inputting the modulated image of this image to the variable shape mask, it is possible to control the irradiation surface shape and irradiation intensity in laser treatment through the mask.

[0016]

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration example of a laser treatment apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of an arm-shaped laser emitting section.

FIG. 3 is a diagram showing a configuration of a flexible tubular laser emitting portion.

FIG. 4 is a diagram showing a configuration example of an optical element that controls transmitted light using polarized light.

FIG. 5 is a diagram showing a configuration example of a variable shape filter.

FIG. 6 is an explanatory diagram of an optical element that utilizes transmission and scattering characteristics.

[Explanation of symbols]

 10 Laser Oscillator 12 Beam Expander 14 Spatial Filter 16 Collimating Lens 18 Variable Shape Filter 20 Condensing Lens 22 Lesion 24 Half Mirror 26 Television Camera 28 Controller 30 Television Monitor 32 Irradiation Optical System 40 Transparent Electrode 42 Polarizing Plate 44 Transmitted Light Material capable of changing polarization characteristics 46 Optical element 50 Laser treatment device 60,62 Medium 64 Transparent electrode 66 Condenser lens 68 Aperture

Claims (3)

[Claims] 1. A laser light source for irradiating laser light, an irradiation optical system for condensing the laser light on a lesion area, an imaging optical system for taking out an image of the lesion area, and a portion taken out by the imaging optical system. A camera for imaging the reflected light reflected on the lesion surface, a shape variable mask provided in the irradiation optical system for changing the irradiation shape of the laser beam onto the lesion surface, and imaged by the camera And a controller for controlling the operation of changing the irradiation shape of the laser beam by the variable shape mask based on the image thus obtained. 2. The laser treatment apparatus according to claim 1, wherein the variable shape mask is a mask that changes the transmission shape of the laser light using liquid crystal. 3. The laser treatment apparatus according to claim 1, wherein the variable shape mask is a mask that changes the transmission shape of the laser light by using fine ceramics.