JPH01270868A - Laser operation device for ophthalmology - Google Patents

Abstract

PURPOSE:To obtain a laser operation device for ophthalmology, which can be utilized for plural operation systems, by composing the device of a light source, which emits an infrared laser light to have a specified central wavelength, and an irradiation optical system to irradiate an operated eye with the infrared laser light. CONSTITUTION:The laser operation device is mostly composed of a light source system 1, an irradiation optical system 2 and an alignment optical system 100 and the light source system 1 has an infrared laser 10 as a laser light source, for example, an HF laser which has the emitting wavelength of 2.9mum. Since the beam cross section of a pulse laser light LB has the rectangular shape of (a)X(b) when the device is used by a stable resonator, the laser beam is enlarged and shaped to the laser beam LB, whose cross section has the almost square shape of (b)X(b), by a cylindrical expander 21. Further, the laser beam diameter is reduced to the cross section of (c)X(c) by a reverse expander 24. An attenuator 30 is arranged between the cylindrical expander 21 and reverse expander 24 and glass boards 31, 32 and 33 are selectively inserted. Then, the energy intensity of the laser beam LB is adjusted. As a result, the laser operation device can be obtained to be utilized to radial keratomy operation or reshaping operation with one device.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ophthalmic laser surgery device. More specifically, the present invention relates to an ophthalmic laser surgery device suitable for multiple surgical procedures such as corneal reshaving and radial keratotomy.

[As a surgery for refractive correction, the corneal surface (epidermis and part of the stroma) is shaped with an ultraviolet laser, and a radial incision is made in the cornea using an ultraviolet laser beam. Radial keratotomy surgery, which involves making incisions, is known.

As a laser surgical device for reshaving surgery, as disclosed in U.S. Pat. No. 4,665,913,
BACKGROUND ART There is known an apparatus that focuses laser light from an ultraviolet laser light source, typically an excimer laser, onto the cornea of an eye to be operated on via a focusing optical system and an optical scanner, and scans the laser beam.

Furthermore, as a device for radial keratotomy surgery, a laser beam emitted from an ultraviolet laser light source consisting of an excimer laser and having a rectangular cross section is shaped into a rectangular shape using an optical telescope consisting of a cylindrical optical system.
Laser surgical devices have been put into practical use that make incisions in the cornea by irradiating a projection of the mask pattern onto the cornea through a mask having a desired incision pattern placed near the cornea.

When corneal cells are incised and excised by laser irradiation,
The following situation is considered.

That is, when a cell is irradiated with a high-power, ultra-short pulse 193 excimer laser, most of the energy is instantly absorbed by water, the main component of the cell, and the cell is evaporated. It is known that some of the cells that did not survive the transpiration (transpiration) would have their DNA damaged due to the high particle energy of the ultraviolet laser, and there was a fear that this could lead to cancer.

In addition, surgical techniques for eye refractive correction are broadly classified into the above-mentioned glue shaping surgery and radial keratotomy surgery, but which surgery to perform depends on the refractive characteristics of the eye to be operated on and the condition of the cornea. Ru.

However, as mentioned above, conventional laser surgical devices are single-function machines that are dedicated to each surgical technique, so it is necessary to use different devices depending on the surgical procedure, and it is necessary to Installing the equipment itself was a huge economic burden.

In addition, excimer lasers are capable of making sharp incisions similar to those of a regular scalpel, so when considering its use for general incisions on the cornea and strong bones, or for punching out the cornea while waiting for a corneal transplant, it is difficult to use the excimer laser with conventional laser equipment. The drawback was that it couldn't be done.

An object of the present invention is to eliminate the above-mentioned conventional drawbacks, and to provide an ophthalmic laser surgery device that can be used for multiple surgeries.

As a means for achieving the above-mentioned object of solving mountain divination, the first basic invention provides an infrared laser as a laser light source, in particular, an HF laser having a wavelength of around 2.9 μm that coincides with the absorption peak of water. laser,
This is a device that uses an Er/YAG laser.

As a means for achieving the above object, a second basic invention includes a collimator optical system that converts a light beam from a laser light source into a parallel light beam having a desired beam diameter, and an objective lens that forms an image of this light beam. A first pattern corresponding to the surgical procedure that can be inserted into and removed from the optical path at a first position equivalent to twice the side focal length, and a second position equivalent to a position near the object side of the objective lens. This is an ophthalmic laser surgery device that has a second butterfly according to different apertures and surgical techniques.

Furthermore, the second basic invention also includes an invention in which the objective lens is constructed of both a spherical lens and a cylindrical lens, which are interchangeable.

The second basic invention also includes an invention in which, when the objective lens is a cylindrical lens, the second pattern arranged at the second position can rotate around the optical axis of the device integrally with the cylindrical lens. There is.

Further, the second basic invention also includes an invention in which, when the objective lens is a spherical lens, the objective lens is movable along the optical axis of the apparatus.

Furthermore, the second basic invention also includes an invention in which an image rotator is disposed between the objective lens and the first position.

Further, the second basic invention described in 1 also includes an invention having a laser beam scanning optical system on the exit side of the objective lens.

As a means for achieving the above object, the third basic invention includes a collimator optical system for converting light from a laser light source into a parallel beam having a desired beam diameter, and a collimator optical system for forming an image of the laser light. a first objective lens, a first pattern according to a surgical technique that can be arranged at a first position between the first objective lens and the collimator optical system, and the first position and the first position. a second objective lens that can be inserted into and removed from the optical path between the objective lens and has an object side focal point at the first position; The ophthalmologic laser surgery device includes a second pattern or a diaphragm that can be inserted into and removed from the optical path.

The third basic invention also includes an invention in which the first objective lens is constructed of both a cylindrical lens and a spherical lens, which are interchangeable.

A third basic invention provides an invention in which, when the first objective lens is a cylindrical lens, the second pattern placed in the second position can rotate around the optical axis of the device integrally with the cylindrical lens. include.

Furthermore, the third basic invention also includes an invention in which, when the first objective lens is a spherical lens, the first objective lens is movable along the optical axis of the apparatus.

The second basic invention also includes an invention in which an image rotator is disposed between the first objective lens and the first position.

Furthermore, the third basic invention also includes an invention in which a beam scanning optical system is provided on the exit side of the first objective lens.

In addition, the fourth basic invention is to obtain a desired corneal surface shape by focusing a laser beam on the cornea and scanning it two-dimensionally to evaporate the portion of the cornea that reaches the interior of the cornea. It is a device. This device includes a measurement device that three-dimensionally measures the surface shape and corneal layer of the cornea, a storage device that stores data on the corneal shape before surgery, and a desired optical property based on this data and the optical properties of the eye. The system includes a computer that calculates the ideal corneal surface shape, determines the required amount of transpiration, and controls the laser beam.

-■ In the second basic invention, when a pattern for radial keratotomy is placed at the first position, the pattern is placed on the cornea of the operated eye placed at a position twice the image side focal length of the objective lens. Images are formed at the same magnification, allowing radial keratotomy surgery to be performed. At this time, in the case of the invention having an image rotator, by rotating the image rotator, the pattern for radial keratotomy can be imaged in any corneal meridian direction.

When a slit opening pattern is placed in the second position and the objective lens is a cylindrical lens, the slit-shaped laser beam can be focused on the cornea of the operated eye, which is placed at the image-side focal point of the cylindrical lens, allowing for radial keratotomy surgery. becomes possible. By changing the width of the slit opening pattern, it is possible to change the focusing width of the slit-shaped laser beam and to change the depth and energy density of the butter on the cornea.

Furthermore, by rotating the cylindrical lens integrally with the slit opening rotor pattern, the slit-shaped beam can be irradiated in any corneal meridian direction.

If the laser beam has uneven intensity distribution within its cross section, move the image rotator 5 to the optical axis 0. It is preferable to rotate by 2, which is the rotation angle of the cylindrical lens 52.

In addition, in reshaving surgery, a circular aperture diaphragm is placed in the second position, the cornea is placed at the image-side focal position of the objective lens, and each time the objective lens is moved in the optical axis direction, the objective lens with the circular aperture diaphragm increases the Depending on the focus, the laser beam can be irradiated onto the cornea with an arbitrary spot size to reshape the cornea.

Furthermore, if the reshaving pattern is placed at the first position, the pattern image can be formed at the same magnification on the cornea placed at a position twice the image-side focal length of the objective lens. By rotating the image rotator according to the type of reshaping pattern, the cornea can be reshaped into a desired shape.

If no pattern or diaphragm is placed at the first and second positions, a high-energy microspot can be focused on the cornea placed at the image-side focal position of the objective lens, and the beam scanning optical system can be driven to perform a laser scalpel. It can also be used as Also,
At this time, corneal cells can be removed as a set of arbitrary trajectories. A diaphragm is placed in the second position (by which the energy density, spot size, and depth of the beam can be adjusted). , and when the second objective lens is inserted into the optical path, the pattern image is formed at the same magnification on the cornea of the operated eye placed at the image side focal position of the first objective lens, and the radial keratotomy surgery is performed. Ru.

At this time, in the case of an invention having an image rotator, a pattern can be imaged in an arbitrary corneal meridian direction by rotating the image rotator.

When a slit-opening rotor pattern is arranged at the second position, the first objective lens is a cylindrical lens, and the second objective lens is moved out of the optical path, a slit-shaped laser is placed on the cornea located at the image-side focal position of the cylindrical lens. The beam can be focused and radial keratotomy surgery can be performed.

By changing the width of the slit aperture, it is possible to change the condensing width of the slit beam and to change the depth and energy density of the pattern on the cornea.

Furthermore, by rotating the cylindrical lens integrally with the slit opening rotor pattern, the slit beam can be irradiated in any corneal meridian direction. In this case as well, the image rotators may be rotated simultaneously as described above.

In addition, in reshaping surgery, the second objective lens is moved out of the optical path, a circular aperture diaphragm is placed at the second position, and the lens is placed on the cornea placed at the image-side focal position of the first objective lens.
By moving the first objective lens in the optical axis direction, the cornea can be reshaped with an arbitrary spot size by defocusing by the first objective lens having a circular aperture diaphragm.

Furthermore, by arranging the reshaving pattern at the first position and inserting the second objective lens into the optical path, the pattern image is displayed at the same magnification on the cornea located at the image-side focal position of the first objective lens. It can be imaged with

By rotating the image rotator according to the type of reshaping pattern, the cornea can be reshaped into a desired shape.

No pattern or aperture is placed in the first and second positions,
And when the second objective lens is moved out of the optical path, the first objective lens
It can focus a high-energy microspot on the cornea placed at the image-side focus position of the objective lens, and can also be used as a laser scalpel by driving the beam scanning optical system. By placing the aperture in the second position, the energy density, spot size, and depth of the beam can be adjusted.

In the fourth basic invention, during reshaping surgery, when the first objective lens (convex lens) is inserted into the optical path, a high-energy minute spot can be focused on the cornea placed at the image-side focal position of the first objective lens. By driving the beam scanning optical system two-dimensionally, it is possible to perform evaporation virtually inside the cornea, and by controlling the energy at each scanning location, reshaving processing can be performed to the desired corneal surface shape. It can be carried out.

FIG. 1 is an optical layout diagram showing an embodiment of an ophthalmic laser surgery apparatus according to the present invention.

This laser surgical device includes a surgical light source system 1, an irradiation optical system 2
, and an alignment optical system 100.

The surgical light source system 1 includes an infrared laser 10 as a laser light source.
, for example, an HF laser with an emission wavelength of 2.9 μm or an Er/YAG laser with an emission wavelength of 2.94 μm. An HF laser may be used with a stable resonator or with an unstable resonator. In the case of stability, the cross-sectional shape of the beam is rectangular, but the intensity distribution is Gaussian. In the case of instability, a beam with high output and good coherence can be obtained, but the cross-sectional shape will be donut-shaped, that is, hollow. Therefore, it is necessary to select a resonator depending on the purpose of use. In some cases, it may also be necessary to shape the beam shape.

Here, we will first describe methods for shaping the beam shape in the case of using a stable resonator and the case of using an unstable resonator. When an HF laser is used in a stable resonator, the beam cross section of the pulsed laser beam LB is shown in Figure 19 as 2.
As shown by 01, it has a rectangle of aXb, for example, a=5imSb=10 cranes. Therefore, by using a cylindrical expander 21 composed of a cylindrical concave lens 22 having an axis perpendicular to the plane of the paper in FIG. 1 and a cylindrical convex lens 23 having an axis parallel to the axis of the cylindrical concave lens 22,
As shown by 02, the laser beam LB is enlarged and shaped into a laser beam LB having a substantially square cross section of bxb.

The laser beam LB emitted from the cylindrical expander 21 is transmitted to the inverse expander 24 consisting of a spherical convex lens 25 and a spherical concave lens 26, as shown at 203 in FIG.
The laser beam diameter is reduced to have a cross section of cxc (for example, c=10 m).

These cylindrical expanders 21 and inverse expanders 2
Reference numeral 4 constitutes a collimator optical system 20 for shaping the laser beam LB from outside the HF laser light source 1 using a stable resonator into a laser beam having a desired beam diameter.

An attenuator 30 is arranged between the cylindrical expander 21 and the inverse expander 24, that is, within the optical path where the beam diameter is maximum (b x b). attenuator
30 is composed of a plurality of anhydrous silica glass plates 31, 32, and 33 having transmittances of several tens of percent. By selectively inserting the glass plates 31, 32, 33 into the optical path, the energy intensity of the laser beam LB is adjusted. For example, the pulse energy of the HF laser ()IHLIO3PCLI is about 100 aJ and the pulse width is about 50 nanoseconds, which corresponds to about 2 M-. For this reason, by placing the attenuator 30 in the maximum beam optical path between both expanders 21 and 24, the high-energy laser pulse LB from the infrared laser 10 of the glass plate 31, 32, 33 constituting the attenuator 30 can be Damage can be prevented.

Instead of the type shown in FIG. 1, the collimator optical system 20 has a cylindrical convex lens 211 on the side of the HF laser 10 using a stable resonance device, and a cylindrical concave lens 212 behind it, as shown in FIG. A cylindrical inverse expander 210,
The expander 213 may have a spherical concave lens 214 on the entrance side and a spherical convex lens 215 on the exit side.

In the collimator optical system 200 having the configuration shown in FIG. 2, the laser beam emitted from the cylindrical inverse expander 210 has a square cross section 204 with a minimum beam diameter of aXa (for example, a=5 m), and the expander 24' The laser beam LB is shaped into a square cross section 203 with a variable beam diameter. In this example, attenuator 3
0 is placed after the expander 213 is ejected.

Laser light is generally a well-parallel light beam, but in reality it has a slight spread angle θ after being emitted from the light source. The same applies to the HF laser 10 using a stable resonator, and as shown in FIG. has a spread angle of θ4 in the direction, and has a spread angle of θ1. ≠θ.

(θ, >θL).

Therefore, when the laser beam LB is shaped by the collimator optical system 20 described above, the spread angle θ of this laser beam is
1, θ, when focusing the laser beam LB or forming a pattern using the irradiation optical system 2, which will be described later, the spread angle θ5, θ of the laser beam itself in the vertical and horizontal directions will change.
Astigmatism is produced due to □, resulting in a decrease in beam focusing ability and pattern imaging ability.

Therefore, as a first method to eliminate this drawback,
As shown in FIGS. 4A and 4B, the optical arrangement of the collimator optical system 200, cylindrical expander 21, and reverse expander 24 in FIG. 1 is changed. That is, the laser beam L is applied to the cylindrical concave lens 22 of the cylindrical expander 21.
When B enters the ideal laser beam L B o at a spread angle θ1 in the vertical direction and at a spread angle θ□ in the horizontal direction H, move the cylindrical convex lens 23 along the optical axis 01 in the direction of the arrow 27. and place it at position 23'.

The spread angle of the light emitted from this cylindrical convex lens 23' is vertically directed, and is set to be θ along with the horizontal direction H. In order to emit the laser beam LB that enters the inverse expander 24 with a spread angle θ parallel to the optical axis o1, the spherical convex lens 25 of the inverse expander 24 is aligned with the arrow 28.
direction and place it at position 25'.

In this way, in the first method, when an HF laser is used in a stable resonator, the cylindrical expander 21 and the inverse expander 24 in the ideal laser beam LB are set at a spread angle θ
1. For a laser beam LB having a θ angle, the distance between the cylindrical convex lens 23 and the cylindrical concave lens 220 constituting the cylindrical expander 21 is shortened, and conversely, the distance between the facing convex lens 25 and the spherical concave lens 26 constituting the inverse expander 24 is shortened. Its characteristic lies in its ability to stretch.

The second method is to replace the cylindrical concave lens 21 of the cylindrical expander 21 with a toric lens 220, as shown in FIGS. 5A and 5B. That is, the object side cylindrical minus refractive surface 220 of the toric lens 220
a is a concave refractive surface having an axis in a direction perpendicular to the plane of the paper.

The toric lens 220 has the function of emitting the laser beam as if it were emitted from the object side focal point F of the cylindrical convex lens 23 of the cylindrical expander 21 when the laser beam LB having a vertical spread angle θ is incident thereon.

On the other hand, the image-side cylindrical plus refractive surface 220b of the Dolly 7 lens 220 has an axis in a direction perpendicular to the cylindrical minus refractive surface 2zOaO axis. When a laser beam having a horizontal spread angle θ8 is incident on the toric lens 220,
It has the function of emitting this beam as a beam parallel to the optical axis OI. The laser beam LB after exiting the cylindrical convex lens 23 by the toric lens 220 becomes an ideal laser beam parallel to the optical axis in both the vertical and horizontal directions.

The third method is a method in which the cylindrical concave lens 22 is composed of two cylindrical lenses 221 and 222, as shown in FIGS. 6A and 6B. That is, the cylindrical concave lens 221 is a cylindrical concave lens with an axis in the horizontal direction, and when a laser beam L B having a vertical spread angle θ is incident thereon, the laser beam LB is emitted from the object side focal point F of the cylindrical convex lens 23. It has the effect of refracting the beam LB. Further, a cylindrical convex lens 2 having an axis perpendicular to the axis of the cylindrical concave lens 221
22 is a laser beam L having a horizontal spread angle θ8.
It has the function of emitting B parallel to the optical axis OI. As a result, the laser beam after exiting the cylindrical expander 21 becomes an ideal laser beam parallel to the optical axis in both the horizontal and vertical directions.

When an unstable resonator is used, the cross-sectional shape of the beam becomes donut-shaped, making it unsuitable for uses other than surgery using a condensed beam scanning method, which will be described later. However, the paper r
App1. Phys, LetterJ (Voi.

52, Magnetics 7. February 15, 1988 issue, pages 530 to 531, if an unstable resonator with the structure shown in Yasui et al. can be obtained, so the beam shape shaping method described above can be used.

Further, when an Er/YAG laser is used as a laser light source, the output beam itself is circular and has a Gaussian intensity distribution, so there is no need for beam shaping at all.

Returning to FIG. 1, the laser beam LB emitted from the collimator optical system 20 is reflected by the infrared reflection/visible transmission type guichroic mirror 4 and enters the irradiation optical system 2.

The irradiation optical system 2 includes an image rotator 5 having a known configuration that can rotate around its tip axis 02, and a scanning rotator that can swing in the X- and Y-axis directions when the optical axis 0□ is the Z-axis direction. It has a mirror 7. A first objective lens 50 is arranged between the image rotator 5 and the scanning mirror 7.

The first objective lens 50 includes a spherical lens 51 and a cylindrical lens 5.
2, and both can be inserted into and removed from the optical path interchangeably. At a second position BB near the price of the first objective lens 50, there is a slit plate 9S shown in FIG. 7 as a second pattern and a circular aperture diaphragm plate 1 shown in FIG.
The OS can be inserted into and exited from the optical path alternatively or simultaneously. Although the spherical lens 51 and the cylindrical lens 52 have the same optical characteristics, the cylindrical lens 52 has a refractive effect only in a direction perpendicular to its axial direction.

The suri throat plate 9S is used for radial keratotomy. The circular aperture diaphragm plate 103 is used for changing and shaping the length of the slit pattern. Slit plate 9S
As shown in FIG. 7, the width d of the aperture 9a is changed, for example, there are four types of slit patterns, ci = 8, 6, 4, and 2 cranes, which can be inserted into the optical path alternatively. It looks like this.

Further, as shown in FIG. 8, the circular diaphragm plate 10S has four types of apertures whose diameters φ are, for example, φ-8, 6, 4, and 2 mm, and can be selectively inserted into the optical path. It looks like this.

As shown in FIG. 9, by simultaneously inserting the slit plate 9S and the diaphragm plate 10S into the optical path, it is possible to obtain many types of slit patterns of slit width x slit length - d x φ.

In this way, a plurality of slit plates 9S and a plurality of apertures 1ios
Instead of obtaining a desired slit pattern by combining the two slit blades 91 and 92, as shown in FIG. Two slit blades 93 that separate
．． An arbitrary d×e slit pattern may be obtained from 94.

When the spherical lens 51 is inserted into the optical path as the objective lens 50, the laser beam emitted from the image rotator 5 enters the objective lens 51 as a parallel beam, and is condensed to the minimum spot at the image-side focal point F1 of the objective lens 51. be done. Then, when the circular diaphragm plate 103 is further inserted into the second position BH, this circular diaphragm IO3 has a luminous flux limiting function 1, and by changing the aperture diameter φ of the diaphragm plate 10S, the spot diameter Sφ at the focal point F□ As shown in Fig. 17, when the image-side focal length of the objective lens is f and the wavelength of the laser beam is λ, the spot diameter Sφ on the focal point Fi can be changed, and the depth of the bont and Energy density can be changed.

When the cylindrical lens 5I is inserted as the objective lens 50 into the optical path, as shown in FIG.
The light is focused in a straight line at the image-side focal point F1 of the cylindrical lens. Then, by further inserting the slit plate 9S at the second position BB, the width d of the slit pattern is changed, and the line width S4 of the linear condensing line becomes 2 t λ. Therefore, the line width S4 of the linear condensing line can be changed, and the depth and energy density of the linear condensing line can also be changed.

Furthermore, by simultaneously inserting the diaphragm plate 10S into the second position BB, the length of the linear condensing line can be changed.

In this embodiment, the slit plate 9S is configured to be rotatable about the optical axis 02 integrally with the cylindrical lens 52. The image rotator 5 may be rotated at the same time as needed. Further, the objective lens 50 is configured to be movable along the optical axis 02.

Position 2F0 of twice the focal length f0 of the objective lens 50
That is, at the first position BB, the first pattern plate 8 is arranged to be removably inserted into the optical path.

This first pattern 8 is a radial slit pattern 81 shown in FIG. 11 as a pattern for radial keratotomy.
, a T-shaped pattern 82, and a parallel line pattern 83 are prepared, and these patterns can be selectively inserted into and removed from the optical path.

The first pattern 8 is a pattern for reshaving, and includes a small circular lobe pattern 84 formed at a desired radial position off the center as shown in FIG. 14A, and an opening diameter as shown in FIG. 15A. A variable iris aperture 85 and a pattern 86 having a ginkgo leaf-shaped aperture as shown in FIG. 16A are prepared, and these apertures are configured so that they can be selectively inserted into and removed from the optical path.

Pattern 8 is an objective lens 50 (mainly a spherical lens 51)
Therefore, the position 2F which is twice the image side focal path LM t +
The image is focused on A.

The alignment light source system 100 of this embodiment is made of He-Ne.
Laser light source 101, concave lens 102, and convex lens 103
It consists of an expander system consisting of a The see-through light from the -Ne laser passes through the dichroic mirror 4 and enters the irradiation optical system 2. Note that the alignment optical system 100
optical axis O0°. and the optical axis 08 of the irradiation optical system 2 are coupled by a dichroic mirror 4.

Next, a method of using the laser surgical device of the first embodiment during corneal surgery will be described.

A) Radial keratotomy surgery ■ A cylindrical lens 52 is inserted into the optical path as the objective lens 50 of the line condensing irradiation optical system 2. Desired slit plate 9 at second position BH
Then, a diaphragm plate 10 is inserted to obtain a linear condensing line having a desired width and length and adjusting energy density and depth as necessary.

The cornea C to be operated on is positioned at the image-side focal position F of the cylindrical lens 51.

The He-Ne laser is rotated around the optical axis of the cylindrical lens 51 and the slit plate 9 (including rotation of the image rotator 5 as necessary) and by operating the scanning mirror 7 so that the condensed light beam comes to a desired position on the cornea. Alignment is performed using alignment light from 101.

Next, after adjusting the attenuator 30 to obtain the desired energy intensity, the number of zero emission pulses for irradiating the cornea with the infrared laser pulse light is adjusted by the cutting depth.

(2) A spherical lens 51 is inserted into the optical path as the objective lens 50 of the pattern imaging type irradiation optical system 2. In the case of correcting only the spherical refractive power of the cornea, the pattern 81 is inserted into the optical path at the first position AA, and in the case of correcting the astigmatic refractive power, the patterns 82 or 83 are inserted into the optical path. The cornea C' to be operated on has the focal length 2 of the spherical lens 51.
Double i! Positioned at f2 Fi.

By rotating the image rotator 5 around the optical axis 0□ and operating the scanning mirror 7, the pattern (81~
83) at the desired position on the cornea.
Align the pattern image by e-Ne laser beam,
After adjusting the energy intensity with an attenuator 30, infrared laser pulse light is irradiated.

B) Reshaping surgery (1) ■ A spherical lens 51 is inserted into the optical path as the objective lens 50 of the defocusing irradiation optical system. A circular aperture stop IO3 is inserted into the optical path at the second position BB.

The cornea C to be operated on is positioned at the image side focal position if F i when the spherical lens 51 is at a predetermined position.

Next, the spherical lens 51 is moved in the optical axis direction to defocus the aperture stop image to obtain a desired spot size, and then the scanning mirror 7 is operated to align the spot to a desired position on the cornea. . Adjustment and alignment of the spot size is performed using a He-Ne laser beam. Next, after adjusting the energy intensity with an attenuator, an infrared laser is irradiated.

(2) A spherical lens 51 is used as the objective lens of the pattern imaging type irradiation optical system 2. A desired one of the patterns 84 to 86 is inserted into the optical path at the first position AA. The cornea C' to be operated on is positioned at a position 2F, which is twice the image-side focal length of the lens 51.

When the pattern 84 is selected, the image low cheater 5 is rotated about the optical axis 02 times. This allows corneal C
A circular pattern image is formed on ', as shown in FIG. 14C. The irradiation energy at this time is the 14th
As shown in Figure B, only the annular portion is irradiated with pulsed light, and its energy intensity E is determined by the attenuator.
30 and the number of pulses of the infrared laser pulse light.

When pattern 85 is selected, the irradiation pattern image onto the cornea becomes circular as shown in FIG. 15C. By changing the diameter of this iris aperture 85,
The diameter of the irradiation pattern image can be changed. Also,
By sequentially changing the aperture diameter of the iris aperture 85 for each infrared laser pulse irradiation, the energy distribution can be changed in the radial direction r, as shown by the two-dot chain line in FIG. 15B.

When the pattern 86 is selected, by rotating the image low cheater 5, the irradiation pattern image onto the cornea C' becomes circular as shown in Fig. 16C''. As shown in Figure 16B, it is possible to obtain an energy distribution that increases from the center to the periphery.

As in the other examples, prior to irradiation with infrared laser pulse light, the scanning mirror 7 is operated using He-Ne laser light to align the irradiated region.

C) Reshaping surgery (II) This is a reshaping surgery by two-dimensional scanning using a condensing LB. A spherical lens 51 is used as the objective lens 50 of the irradiation optical system 2. No pattern is inserted into the optical path at the first position AA and the second position fiBB.If the energy density requires adjustment of the spot depth, a circular diaphragm 10 with a desired aperture diameter φ is placed at the second position BB. into the optical path. The eye to be operated on is positioned near the image-side focal point of the objective lens. By scanning the scanning mirror 7 two-dimensionally, a two-dimensional shaping surgery that reaches substantially the inside of the cornea is performed.

Specifically, it is performed as follows. Optical characteristics of the affected eye measured with an autorefractometer or the like before surgery, a three-dimensional corneal shape measuring device that is part of this device, such as a PKS-1000 photokeratoscope 303 manufactured by Sun Contact Lens Co., Ltd., and corneal thickness. Data on the affected eye obtained by the measuring device 304, for example, an ultrasonic axial length meter ES-100 manufactured by Tokyo Kogaku Kikai Co., Ltd., is stored in the storage device W305 in the computer 306 via the keyboard 307 or directly.

Based on these data, the computer 306 calculates the three-dimensional amount of transpiration and the corresponding number of pulses required to bring the affected eye to desired optical characteristics. Based on these data, the computer 306 also controls the scanning mirror 7 while monitoring the pulse output and pulse sheet from the laser with the pulse counter 301, and data regarding this control is sequentially displayed on the monitor 302.

D) A spherical laser 51 is used as the objective lens 50 of the laser scalpel irradiation optical system 2. No pattern is inserted into the optical path at either the first position AA or the second position BB. If it is necessary to adjust the energy density or spot depth, a circular diaphragm 10 having a desired aperture diameter φ may be inserted into the optical path at the second position iBB.

The eye to be operated on is positioned at the image-side focal position of the objective lens. By scanning the scanning mirror 7, the cornea and sclera can be incised along an arbitrary trajectory.

In the first embodiment described above, when the first pattern 8 is placed at the first WAA, the pattern image is formed at the same magnification at the position 2Fi, which is twice the focal length of the objective lens. However, the present invention is not limited to this, and if it is desired to irradiate the cornea with the first pattern 8 in a size other than the same size, this can be achieved by moving the cornea forward or backward from the position by 2F. At the position of the present invention, the laser beam that passes through the first pattern 8 is only a parallel beam, so even if the cornea deviates from the 2F position, there is almost no deterioration in the shape of the pattern image, and only its size changes. is possible.

In addition, by connecting a fiber to this device, it is possible to freely incise along a desired trajectory by moving the fiber exit end without operating the scanning mirror 7, and by inserting the fiber into the eye, the vitreous body and Retinal surgery is also possible.

In the surgical procedure described above, the slit plate 9S and the diaphragm 10S as the first pattern, the insertion into the optical path (of each pattern of the second pattern 8), the replacement of the first objective lens,
Although the operation of the scanning mirror 7 and the rotation of the image rotator 5, slit plate 9S, and cylindrical lens 52 may be performed manually, the combination, rotation, and movement amount of each of these components may be programmed in advance according to the surgical technique. In addition, it may be configured to be automatically controlled by a microprocessor sensor (not shown).

As shown in FIG. 1, a second objective lens 6 with a focal length f01 is located between the second position BB and the image rotator 5.
is configured to be able to be inserted into and removed from the optical path so that its price focus F,' coincides with the first position AA.

As a result, even when performing radial keratotomy surgery or shaping surgery by inserting the first pattern 8 into the first position AA, the operated cornea C can remain fixed at the image-side focal position Fi of the first objective lens 50. It becomes like this.

According to the present invention, a single laser surgical device can be used for both radial keratotomy surgery and reshaping surgery.

Furthermore, it is possible to provide a laser surgical device with a high degree of freedom in which various types of radial keratotomies and shaping surgeries can be performed by exchanging various patterns and objective lenses for each surgical method.

Furthermore, it is possible to provide a multifunctional laser surgical device that can be used not only for radial keratotomy surgery and shaping surgery, but also as a laser scalpel.

[Brief explanation of the drawing]

Fig. 1 is an optical layout diagram showing an embodiment of the present invention, Fig. 2 is an optical layout diagram showing another example of the collimator optical system, and Fig. 3 is a perspective schematic diagram for explaining the spread angle of the laser beam. , Figures 4A and 4B are optical layout diagrams of the collimator optical system for correcting the divergence angle, and Figure 5A is a cylindrical extract showing another example of the collimator optical system for correcting the divergence angle. FIG. 5B is a plan view of a portion of the cylindrical expander shown in FIG. 5A. FIG. 6A is another example of a collimator optical system for correcting the divergence angle. 6B is a plan view of a portion of the cylindrical expander shown in FIG. 6A; FIG. 7 is a plan view showing an example of a slit plate; FIG. is a plan view showing an example of a circular aperture diaphragm plate, Fig. 9 is a plan view showing a combined state of a slit plate and an aperture plate, Fig. 10 is a plan view showing another example of a slit plate, and Fig. 11 is a radial keratin plate. FIG. 12 is a plan view showing another example of the first pattern for radial keratotomy; FIG. 13 is another example of the first pattern for radial keratotomy. Fig. 14A is a plan view showing an example of the first pattern for beam shaping; Fig. 14B is a graph showing the irradiation energy distribution according to the pattern of Fig. 14A; Fig. 14C is the graph of Fig. 14A; FIG. 15A is a plan view showing another example of the first pattern for reshaping; FIG. 15B is a graph showing the irradiation energy distribution according to the pattern of FIG. 15A; FIG. 15C 16A is a plan view showing still another example of the first pattern for beam shaping; FIG. 16B is a diagram showing the irradiation energy distribution according to the pattern in FIG. 16A. Figure 16C is a diagram illustrating the irradiation pattern image according to the pattern in Figure 16A, Figure 17 is the relationship between the aperture diameter of the lens and aperture (and slit) and the diameter (and width) of the spot (and condenser plate). FIG. 18 is a schematic perspective view showing the relationship between the cylindrical lens 52, the slit plate 9, and the linear condensing line, and FIGS.
The figure is a cross-sectional view of a pulsed laser. 8...First pattern 9S...Second pattern 10...Infrared laser (laser light source) 10S...Aperture 10...Collimator optical system 50...Objective lens (first objective lens) Fi... Image-side focal position 2 of the objective lens Fi... Position 2 twice the image-side focal position of the objective lens
Fo...Position AA twice the image side focal position of the objective lens
...First position BB...Second position Fig. 2 Fig. 3 Fig. 7 Fig. 8 Fig. 9 Fig. 1O Fig. 1I Fig. 12 Fig. 13

Claims (22)

[Claims] (1) An ophthalmologic laser surgery device comprising an infrared laser light source for emitting infrared laser light, and an irradiation optical system for irradiating the infrared laser light to an eye to be operated on. (2) The center wavelength of the infrared laser beam is approximately 2.9 μm.
The ophthalmic laser device according to claim 1, characterized in that: (3) The ophthalmic laser device according to claim (2), wherein the infrared laser light source is an HF laser. (4) The ophthalmic laser device according to claim 2, wherein the infrared laser light source is an Er/YAG laser. (5) an infrared laser light source for irradiating infrared laser light; a collimator optical system for converting the laser light into a parallel beam having a desired beam diameter; and the laser light from the collimator optical system. an objective lens for forming an image; a first pattern that can be inserted into and removed from the optical path at a first position that is twice the object-side focal length of the objective lens; an object-side focal point of the objective lens; An ophthalmic laser surgery device comprising a second pattern or a diaphragm that can be inserted into and removed from the optical path at a second position near the side. (6) The ophthalmologic laser surgery apparatus according to claim (5), wherein an image rotator is disposed between the first position and the second position. (7) Claim (1) characterized in that the objective laser comprises a spherical lens and a cylindrical lens that are mutually interchangeable.
Or the ophthalmic laser surgery device described in (6). (8) The ophthalmologic laser surgery apparatus according to claim (7), wherein the cylindrical lens is rotatable about a positional optical axis integrally with the second pattern. (9) The ophthalmic laser surgery apparatus according to any one of claims (5) to (8), wherein the objective lens is movable along the optical axis of the apparatus. (10) Any one of claims (5) to (9), further comprising a scanning optical system on the image side of the objective lens for scanning the laser beam emitted from the objective lens. The ophthalmic laser surgery device described. (11) The ophthalmic laser surgery apparatus according to any one of claims (5) to (10), wherein the laser light source is an HF laser. (12) The ophthalmic laser surgery apparatus according to any one of claims (5) to (10), wherein the laser light source is an Er/YAG laser. (13) an infrared laser light source for irradiating infrared laser light; a collimator optical system for converting the laser light into a parallel beam having a desired beam diameter; and a collimator optical system for collimating the laser light from the collimator optical system. a first objective lens for imaging; a first pattern that can be inserted into and removed from the optical path at a first position between the collimator optical system and the first objective lens; and the first position. and a second objective lens that is removably inserted into the optical path between the first objective lens and the first objective lens, and has an object side focal point at the first position; An ophthalmic laser surgery device comprising: a second pattern or a diaphragm that can be inserted into and removed from the optical path at a nearby second position. (14) The ophthalmic laser surgery apparatus according to claim (13), wherein an image rotator is disposed between the first position and the second position. (15) The ophthalmologic laser surgery apparatus according to claim (13) or (14), wherein the first objective lens includes a spherical lens and a cylindrical lens that are mutually interchangeable. (16) The ophthalmologic laser surgery apparatus according to claim (15), wherein the cylindrical lens is rotatable about the optical axis of the apparatus integrally with the second pattern. (17) Claims (13) to (16) characterized in that the first objective lens is movable along the optical axis of the device.
) The ophthalmic laser surgery device according to any one of (18) An optical scanning means for scanning a laser beam emitted from the first objective lens is disposed on the image side of the first objective lens. The ophthalmic laser surgery device according to any one of the above. (19) The optical scanning mechanism includes a device that three-dimensionally measures the surface shape and corneal thickness of the cornea, a device that stores data on the corneal shape before surgery using this device, and a device that stores data on the corneal shape before surgery, and this data and the optical characteristics of the eye. From this, calculate the ideal corneal surface shape to obtain the desired optical properties, determine the required amount of transpiration,
19. The ophthalmic laser surgery device according to claim 18, characterized in that the device includes a computer and a driver that control both scanning and pulse aspects of the laser beam. (20) Claim (13) characterized in that the laser light source emits laser light having a center wavelength of about 2.9 μm.
) to (19). (21) The ophthalmic laser surgery apparatus according to claim (20), wherein the laser light source is an HF laser. (22) The ophthalmologic laser surgery apparatus according to claim (20), wherein the laser light source is an Er/YAG laser.