JPH0262252B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to ophthalmic treatment, and in particular to surgery on the outer surface of the cornea.

[Conventional technology]

Human surgeries, including corneal transplantation and keratotomy, have traditionally required skilled manipulation of cutting instruments.

However, even if a sharp blade is used, simply penetrating the surface of the cornea creates horizontal pressure on the somatic cells that are moved to both sides of the wound. It means to give.

This horizontal pressure damages multiple cell layers on both sides of the wound, greatly impairing its ability to heal and resulting in the formation of scar tissue.

[Problem that the invention seeks to solve]

Therefore, Japanese Patent Application No. 59-239583 filed by the inventor provides a background explanation on the effects of various useful laser emission wavelengths in ophthalmic treatment, particularly in treatment of the corneal surface.

Radiation at ultraviolet wavelengths has been described as desirable due to its high photon energy. This photon energy has a very efficient impact on cellular tissue, and the molecules of the tissue are decomposed by the optical impact, resulting in tissue removal by photolysis.

Molecules at the irradiated surface are broken into smaller volatile fragments without heating up any remaining underlying layers. This removal mechanism is photochemical, ie, direct destruction of internal bonds between molecules.

The effects of photoheating and/or photocoagulation are neither distinctive nor noteworthy in ablation at ultraviolet wavelengths. And cell damage adjacent to photolytic removal is of little concern.

The intensity steps of this removal process are based on ultraviolet wavelengths (approximately
For radiation exposure at wavelengths in the range of 400 nm or less, an energy density of 1 joule/cm ² is required to cut a depth of 1 micron (1 μ).

In an earlier patent application, in order to inscribe the surface of the cornea,
Techniques are disclosed for scanning a laser beam across the surface in a controlled pattern to impart new curvature to the surface to achieve optical correction of an eye with an optical defect.

However, the scanning and scanning controls for implementing such techniques have the disadvantage of being relatively complex and expensive.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide improved apparatus and techniques for surgically operating the outer surface of the cornea.

Another object of the invention is to simplify and reduce the cost of devices and techniques for surgically correcting the optical characteristics of the eye by surgical treatment of the outer surface of the cornea.

A particular object of the present invention is to provide surgical techniques and devices that reduce myopic, hyperopic and/or astigmatic conditions in the eye.

Another specific object of the present invention is to provide an improved surgical technique for corneal transplant surgery.

A further specific object of the invention is to provide an automatic device for safely performing ultraviolet irradiation in corneal surgery.

Another object of the invention is to achieve the above objectives without using scanning techniques or devices.

[Means for solving problems]

According to the invention, for a non-scanning laser characterized by ultraviolet radiation irradiated with such energy that it is possible to photolytically ablate the cornea, i.e. the epithelium, Bowman's membrane and stromal level,
The above objectives are achieved using a device that effectively fixes the position of the eyeball.

The irradiation flux density and exposure time are controlled to reach the desired ablation depth.

Unlike the scanning process disclosed in the earlier application, the scoring operation of the present invention is accomplished by controlling the change in size of the projected laser spot during a given process, and the range of spot sizes is is from the maximum value covering the entire range to be treated to the planned minimum acceptable value.

In one embodiment, a variable focus lens on the optical projection path is the means to vary the spot size, and in other embodiments, an index mask or mirror is employed. In these two embodiments, the critical time allocation, which is a function of the spot size, allows the curvature of the optically defective cornea to be detected in advance and to ultimately result in the desired optically normal cornea. It is to be.

Spot size control is disclosed not only for annular curvature correction, but also for cylindrical correction to reduce astigmatism, and is also discussed in relation to corneal transplant procedures.

Embodiments of the present invention will be described below with reference to the drawings.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

In FIG. 1, the clamping means 10 is arranged so that the eye 11 to be treated (lying face up) is aligned with the downwardly curved portion of the central axis 12' of the beam output from the fixed laser device 13. (i) Immobilize the patient's head. The fixed laser device 13 is supported by a table or other base 13'.
The optical system for laser beam irradiation to the eye 11 is
It includes a zoom lens device 14 with a reversible motor 15, by means of which the spot size of the laser on the eye 11 is varied from a predetermined minimum diameter to 3 or 3, depending on the anterior corneal area to be subjected to the laser action.
Can be varied up to a maximum diameter of 3.5mm radius.
Cabinet 16 contains the power supply for the laser device. Furthermore, the cabinet 16 includes programmable microprocessor means for controlling the exposure and beam (spot) size at the axis 12, as will become more apparent later.

Preferably, the clamping means 10 has the reference numeral 17
It has a head fixation means for stabilizing the patient's head in the area of the patient's temple indicated by , and an eyeball holding means (18 in FIG. 2) stabilizes the patient's head in the area of the cornea sclerosis.
It covers the surrounding area. Further, desirably, the optical fixing means 20 includes the table or the base 1.
3'. The optical fixation means 20 has a viewing crosshair and a lens so that the untreated eye 11' can see the crosshair. The line of sight 21 of the means 20 is parallel to the axis 12 and adjustment means (not shown) provide the necessary adjustable offset for the patient's pupil distance and the special positioning of the means 20 from the axis 12. Can be adapted to mounting offsets. For treatment of the other eye 11', eye 11 can be fixed with similar fixation means, together with other fixation means (not shown) and corresponding adjustable offset means. Alternatively, the fixing means 20 can be adjustably mounted with a modified offset on the opposite side of the zoom lens arrangement 14. For treatment of the eyeball 11', the clamping means 1
0 is then indexed laterally to the laser 13 to the extent that it aligns the axis 12 with the eye 11' to be treated, thereby positioning the eye 11 for use with the fixation means.

The eye retention means 18 of FIG. 2 includes a hollow ring having a converging axial end wall 23 of air-permeable material contoured to retain the eye through the membranous-corneal region. Side connection 24 to vacuum pump
makes the wall 23 hold the eye. External projection or flange means 25 are the means indicated by the word connection in FIG. 2 (not shown in FIG. 1 for simplicity).
via the laser 13 and zoom lens device 14
The fixing means 18 is separated and connected.

Laser 13 preferably emits ultraviolet light, ie, wavelengths substantially less than 400 nanometers. The gas laser is a neon fluoride laser.
351nm, 337nm with nitrogen laser, 308nm with neon chloride laser, 248nm with krypton fluoride laser, 193nm with argon fluoride laser, and 193nm with fluorine laser
Frequency doubling techniques, which generate a wavelength of 157 nm and have been applied to other lasers in this range, including crystal lasers, provide yet another source.

Lambda, Götzteingen, Germany
One of the currently commercially available lasers from Physik GmbH, such as the argon fluoride laser model EMG-103, is sufficient for Laser 13, with a maximum energy per pulse of 200 millijoules,
A pulse repetition rate of 200 seconds, 3 x ¹⁰⁵ shots (pulses) is possible with a single type of included gas before reducing to half the rated power at this pulse rate, but for use in the present invention the full rated power is is not required. The pulse width is approximately 15 nanoseconds, and the typical beam shape is square. However, as shown,
The aperture in mask 26 reduces the laser beam to a circular cross section. The optical element of lens 14 may be comprised of quartz, calcium fluoride, magnesium fluoride, or other material suitable for laser beam conditioning.

FIG. 3 is a diagram for explaining the effect of laser output that is changed depending on the settings of the zoom lens device 14. As already mentioned, the zoom lens device 14 allows the spot size in the eye 11 to be varied from a minimum diameter indicated by reference numeral 28 to a maximum diameter indicated by reference numeral 29. Third
Although the figure shows a plurality of other intermediate circular spot sizes, the zoom adjustment of the zoom lens device 14 can be varied continuously, so that the zoom pulse during continuous changes during the zoom adjustment. There is no need to expect discrete circular spots of different diameters, except that intermittent transmission means that each pulse is projected with a slightly different spot size.

4 and 5 illustrate the application of the present invention to the optical modification removal of the outer surface 30 of the eye to eliminate myopia. Myopia means that the radius of curvature of the outer surface 30 is too short for distant objects to be imaged on the retina. On the other hand, dashed line 3
1 indicates the final curvature to which the outer surface of the cornea is to be modified to obtain a diopter (unit of refractive index) reduction effect. To obtain curve 31, the minimum desired photolysis is at the outer boundary 29 and the maximum is at the center. This can be accomplished by programming the microprocessor to sequentially vary the projected spot size (via adjustment of lens 14) in a predetermined series of laser pulses. Change spot size from minimum (28) to maximum (29)
The result is the same whether you enlarge it to 100 degrees or decrease it from the maximum (29) to the minimum (28). Of course, for each laser pulse or "shot," the corneal ablation penetration (i.e., depth) will be a function of the energy density delivered and, therefore, necessary for a given increase in ablation penetration. The larger the diameter of the projection spot, the greater the number of pulses.

Figure 5 shows the continuously decreasing diameters D ₁ , D ₂ , D ₃
... is a simplified diagram to illustrate the progressive removal effect of a series of laser spot projections at D _o . The minimum energy density is at the maximum diameter D ₁ and a minimum penetration can be obtained, although the penetration is uniform over the entire spot area of diameter D ₁ . In the next step D ₂ of decreasing diameter, there is a greater energy density and the penetration is cumulative with that of the first shot for the common area with the first shot. The cumulative penetration effect continues with each shot of successively reduced diameter, so that a new larger radius of curvature appears due to the stepwise reduction in projected spot size. However, for a sufficiently large number of laser pulses (and therefore even discrete steps), the individual steps are considered non-discontinuous and a new spherical outer surface that is sufficiently smooth forms on the cornea. be done. This is especially true when a thin epithelial layer spreads out as a smooth protective covering of the new surface.
This becomes certain after 2 days after surgery.

The foregoing discussion of FIGS. 1-5 assumes a pulsed laser, as exemplified by an excimer laser. However, other lasers are known which emit at energy levels suitable for current use and at ultraviolet wavelengths. These other lasers will emit continuously for a controlled period of time. For example, an organic dye laser using a suitable organic dye can produce laser emissions in the 380 nm region when pumped by an ultraviolet laser source such as a continuous wave, quadruple frequency neodymium YAG laser operating at 266 nm. can be made to generate. In this case, the 380 nm organic dye laser radiation is potassium diuterium phosphate (KDP).
The frequency can be doubled to bring the emission wavelength to 190 nm by a crystal or a suitable non-linear crystal such as a potassium-titanium-phosphate (KTP) crystal. 1 to 5 also show other cases in which axis 1 is
The radiation of the ultraviolet laser on 2 is of continuous wave nature, while the zoom lens device 14 is driven continuously by a program in the cabinet 16 to give a predetermined change in the projection spot size over time. , which provides a myopia-correcting change in curvature from curve 30 to curve 31 during the course of the processing time. As a result, the dimensions of the spot (at eye 11) either expand continuously from a minimum (28) to a maximum (29) or contract continuously from a maximum (29) to a minimum (28). become.

In the embodiments of FIGS. 6 and 7, in order to provide a similar myopia-correcting curvature change to the anterior surface of the cornea,
Mask technology is used instead of the zoom lens technology of FIG. Such a mask technique replaces the lens 14 with a suitably programmed variable aperture membrane that is continuously varied. However, in the illustrated example, a single precision mask plate 35 is used. This mask plate 35 is rectangular and is mounted (by a device not shown) on a coordinate device movable in each or both of two orthogonal axes X-Y. Each of the mask openings arranged in a grid in plate 35 is circular and their dimensions vary incrementally. Thus, the diameter of the first row of mask openings varies from the first opening 36 to the last opening 3.
It gradually decreases in that order up to 6'. In the adjacent example, the first and last apertures are indicated at 37 and 37', the diameters of these apertures also decreasing progressively. Also in the third row, the diameter gradually decreases from opening 38 to opening 38'. In the last row, too, the diameter gradually decreases from the opening 39 to the smallest opening 39'. The X-Y coordinate drive system 40, under the control of the microprocessor 41, continuously moves the mask plate 35 in the X and/or Y directions to correct its position. The microprocessor 41 is now configured to allocate the number of excimer laser "shots" (i.e., in the case of a CW laser, to allocate various controlled pulse durations) in the dimensions of the individual mask apertures. having a programmable device, thereby:
A given desired removal or "sculpture" is made that predictably modifies the optical performance of the eye 11. As shown, the pairs of photoelectric elements 41 and 41', 42 and 42' are
Each mask aperture is spaced so that it is indexed to the laser projection axis 12. That is, these photoelectric elements detect grid lines such as the X-direction grid lines on either side of a given mask aperture 37'' (FIG. 7) and the Y-direction grid lines on both sides of that mask aperture 37'', thereby detecting It ensures that the microprocessor 41 interlocks the objective and corrects the position of the mask aperture on axis 12 before firing the next laser pulse represented by synchronization line 45.

In the configurations of FIGS. 8 and 9, the myopia-correcting engraving is moved from one of successive mask apertures in different regions through positional movement (about the index axis 50') based on the angular index of the mask disk 50. Move to the other side. That is, the disk 50 has mask openings from a maximum opening 51 to a minimum opening 52 that are continuously arranged around the periphery. The radial markings indicated at 53 for the apertures 51 correspond to the angle at which a given aperture is correctively directed in position on the laser projection axis 12 . Disc 50 is mounted on an annular ring 54. This annular ring 54 has a counterbore formed at a marked position in the center of the disc 50. The ring 54 also has a rotational drive signal generator 56.
edge driven (i.e. driven by applying a force to the periphery) by suitable means 55 under the control of . Furthermore, the programmable microprocessor 57 is capable of controlling the rotary drive system 55, 56 for a predetermined allocation of laser pulses to a given mask aperture, and the photoelectric element 59 is Matching the individual radial marks for the defined mask aperture area achieves the desired correction of the corneal contour based on the laser pulse synchronization signal via synchronization line 58.

FIGS. 10 and 11 show that the device of FIG. (Figure).
Here, a different mask disk 62 is used in place of the mask disk 50 in FIG. In this mask disk 62, each position of the marks (for example 63) forming a certain angle with respect to each other has a radius of 3.5, for example.
mm basic apertures define the outer edge of each of the annular arrays of apertures arranged at an angle. These annular openings are created by central opaque mask spots of varying diameter. Thus, in the smallest annular region 63' (corresponding to the radially extending mark 63), the central opaque spot is circular, close to the diameter of the basic aperture, and the first or smallest annular region 63' is make. At the next mark 64, the inner diameter of a slightly thicker annular region 64' is defined by a central opaque spot of slightly smaller area. A similar difference occurs as the equiangular shift (with respect to the coordinate axis of the disk 62) occurs;
This continues until the maximum annular opening 65' is reached. At this angular position 65, the diameter of the central opaque mask is at its minimum. In the use of disk 62 in conjunction with the positioning and control system of FIG. Although it occurs over a wide area, the minimum intrusion occurs in a narrow area, thereby reducing the extent of the new corrected contour 61.

The configuration of FIGS. 12, 13, and 14 is as follows:
It is further shown that the above-described principles of the invention can be used for corrective sculpting of the cornea to achieve a Fresnel-type distribution of desired final curvature, resulting in correction of hyperopia or, as shown, correction of myopia. . Such surgery (ie, Fresnel type) is used when, in the judgment of the surgeon, a single smoothly developed corrective curvature necessarily requires excessive removal of tissue in the peripheral area of the deep cut. To avoid cuts that are too deep, Figures 12 and 13 show that the final reduced curvature surface is 7 as shown at 31 in Figure 4.
It shows that it increases in a circular manner within the area limited by 0. In the outer ones 72 of these annuli, the curvature and depth of the cuts are determined by a continuous curve 71
(i.e., without Fresnel steps). However, the intermediate annular region 73 is
Continuity of curve 71 is effectively achieved with a smaller amount of corneal ablation. Finally, inner circular region 74 effectively obtains curve 71 with minimal removal of corneal tissue.

The removal of tissue in the center is shown in Figures 12 and 1.
It is indicated by Δ74 with respect to the Fresnel cut 74 in Figure 3, and the removal of tissue in the center is a modified single curved surface 71 that is developed relatively smoothly.
is only a small fraction of the maximum removal depth Δ71 required to achieve a similar optical correction at . FIG. 14 shows that the disk 50 of FIG. 8 can be replaced to achieve a Fresnel type cut of the size described above for different annular bodies 72, 73, 74, and a type compatible with the system of FIG. A rotating mask disk 75 of the index is shown. (at position 76') Annular mask 7
Starting with the largest area of 6 and the first of disk 75
Proceeding in a sector of 120°, the succession of openings in the mask disk is due to the central mask spot in a certain area.
It will be appreciated that in connection with progressively decreasing the diameter of the outer circumference, the radius tends to decrease. The programmable means (microprocessor) 57 (of FIG. 8) uses the programmed distribution of this first sector-shaped annular mask opening to achieve the dash-dotted line 71 within the outer annular portion 72 and the laser pulses. It will be appreciated that it functions as a control for spot positioning. It will be appreciated that in establishing curve 71' within intermediate annular portion 73, the succession of annular mask openings similarly achieves a second sector shape (not shown) of mask disk 75. and finally, through a variable succession of gradually decreasing circular aperture indices, starting with the mask aperture diameter of the largest area (circumference 74), and then the third
through the sector, decreasing to the smallest opening 78 at position 78' and approaching position 76' (of the first sector), the curve 71' being inwardly cut by the programmed projection of the laser spot on axis 12. circular area 7
Established within 4.

The diagrams in Figures 15 and 16 show the development of a correction for astigmatism by a pulsed ablation laser in a rectangular beam section where the width of the rectangular beam section is varied to create a cylindrical profile of cumulative ablation. 2 illustrates the variable hole or scale mask technique of the present invention. This is a slit or diaphragm of variable width and the ability to rotate the direction in which multiple dimensions of the slit are located, i.e. based on conventional measurements of the intensity and angle of the cylindrical diopter of a particular astigmatism, the laser beam This can be done by masking the However, in the configuration shown in FIG.
It is. In the section shown in FIG. 16, these openings proceed from the largest area opening 81 to the smallest area opening 81'. The central axis of symmetry of each of these openings is the opening 81.
It is marked as 82 for. Preferably all such marks are of equal extent.

Elongate plate 80 is a slide guided by means 83 forming one end of a rotatable mask support disk or ring 84. And the guide means 8
3 is located on the longitudinal axis 86 of the diametrically symmetrical slot of the ring 84. The manual operation means 85 is
By observation through a fixed pointing mask 87 with respect to the edge mask on the ring 84 (edge drive on the ring 84 to selectively provide an oblique orientation of the elongated plate 80 near the laser projection line 12). The bidirectional sliding signal generator 88 is suitably synchronized by an optical transducer 90 that follows the trajectory of the mask 82 which can be applied to a particular index mask opening, positioned with laser pulse control, etc. The mask opening 89 is under the control of the microprocessor 89 with respect to the slide 80. The mask opening described above can certainly be located on the laser beam projection line 12.

In using the invention for laser surgery on eyes that require both astigmatism and spherical correction, the astigmatism correction is preferably the first of two procedures, as shown in FIGS. 15 and 16. This is considered advantageous since astigmatic errors are generally less severe than spherical errors. As a result, a deopter with less cylindrical surface removal is included for the subsequent sphere correction procedure. Furthermore, eliminating or substantially eliminating astigmatism in the first step configures the anterior surface of the cornea to be substantially spherical. This substantially spherical surface (which is naturally myopic or hyperopic) can also be adjusted to the desired profile (or spherical surface) for corrective vision. In particular, as with the present invention, all ablation laser spots (all of the effective mask apertures) are effectively focused on the optical line of the eye.

Quite apart from the variable depth feature of corneal tissue (FIGS. 4 and 10), the present invention provides for the removal of a predetermined depth during preparation of a corneal transplant reaction onto a single intact area of the cornea. give. In Figures 17 and 18 the cornea of eye 11 is exposed to a series of laser pulses masked over the same area of diameter D, e.g. It will appear to produce a curved base or dimpled curved surface 95 for the position. Optionally, in FIGS. 17 and 18, the cornea of eye 11 has a constant diameter D.
Removal (a) through a similar mask as above and at the rate of removal (b) for a given duration (exposure time) of the laser beam to achieve the desired depth of penetration.
exposed to constant intensity (CW) laser exposure such that

Furthermore, for corneal transplantation procedures, the above-described device would appear even more beneficial in preparing the insertion of the cornea to be transplanted and within the recess 95. The donated eye is held reversibly fixed as shown at 18 in FIG. By "reversible" it can be seen that the method of flange 25 provides for either the epithelium or the endothelium of the donated eye to be exposed centrally to the laser beam 12, so that the donated eye is It can be seen that for the latter position, the iris and other areas not required due to corneal hardening are removed for the first time for corneal surgery. The preferred procedure is to first expose the inside of the donated corneal depression to laser action. Such action can be achieved by exposure to a circular area of time CW or by many pulsed laser spots of a circular area exceeding the diameter of the indentation 95, at least sufficient to remove tissue to a predetermined depth within the donated matrix. (Accomplished through this process) Moreover, the arrangement of the holding means 18 (and in particular the finished corneal working unit) is reversed in order to expose the convex outer side of the donated cornea to the laser action. Laser action on the outside consists of two stages. First, (exceeding the diameter of depression 95)
A number of laser pulses in a circular area are exposed CW in time, thereby ablating at least the epithelium to a depth that preferably exceeds the depth T ₂ of the depression 95 and achieves the implant thickness T ₁ . A scanner (not shown, but of the type disclosed in pending patent application no. 552,983) then sequentially applies successive laser pulses in a circular pattern until the desired implantation is achieved. It is operated in a line cutting mode to follow the circumference of a circle designed to be received precisely within the recess 95 of. In transplantation, the donated matrix is positioned in the patient's desired matrix and sufficiently freely to contact the endothelium. The graft is then sutured.
After removal of the suture, the outer surface of the eye 11 and its implant 9
6 has the appearance shown in FIG. 18, with the implant protruding beyond the adjacent area of the patient's cornea, and this protruding surface of the implant being at the same level as desired with the uncarved adjacent tissue of the patient's eye. It may also be deformed by the laser described above carving the final contour consistent with the boundary. Furthermore, it is to be understood that, depending on the surgical decision, such final incisions may impart a curvature that may or may not result in a predetermined change in the optical performance of the eye.

It will be seen that the above-described method and apparatus achieve all stated objectives and readily provide a controlled procedure for correcting ocular abnormalities resulting from corneal curvature.
The easy-to-remove penetration of the laser beam procedure maintains a relatively innocuous slice of corneal thickness, and at any depth of penetration, natural tissue ridges protect the sculpted area within days after surgery. Gives epithelial coverage. Programmable adjustment of the laser beam size and shape (circular, annular or rectangular) in relation to the number of pulses at a given size and shape produces predictable and controlled changes in curvature and eliminates cylindrical and spherical errors. is removed or substantially reduced, providing great comfort and benefit to the patient.

Although the invention has been described in detail with respect to various described embodiments and modes, it is to be understood that modifications may be made without departing from the scope of the invention. for example,
The above-mentioned manual operating means 85 for presetting the angle at which astigmatism correction is to be achieved, the angular input data for automatic operation, are disclosed in a concurrent application filed by the inventor on January 16, 1985. The astigmatism correction angle may be generated by a diagnostic device or method such as that described in pending patent application Ser.

Also, by way of example, achieving astigmatism correction by cylindrical carving does not necessarily require the index slot technique of FIGS. 15 and 16. As in the first alternative method (Fig. 19), the variation of the slot width
This may be accomplished electromechanically by microprocessor-controlled means 100 for differentially driving opposite side plates 101-102 of a variable width aperture whose two axes are always centered. , board 101
-102 is slidably mounted on an annular base 104 whose rotation can be adjusted to the angle at which the astigmatism is to be corrected (as suggested by the paired arrows 103). In a second alternative (FIG. 20), a cylindrical zoom lens device 105 is used (as indicated by the paired arrows 106) to shape the laser beam 12 projected into a line of variable width. The line is connected to the helical drive 10 relative to the rim 108, which is mounted annularly relative to the zoom device 105.
7, it is possible to set the angle at which the astigmatism is to be corrected.

Figures 21 to 26 illustrate different embodiments of the invention in which the variously described series of spot shapes for achieving laser ablated corneal curvature are produced by reflective techniques. Since the parts in these figures are identical to the parts in Figures 6, 7, 8, 9, 11 and 14, the same number is appropriately used 100 consecutively.

In the embodiment of FIGS. 21 and 22, a transparent plate 135, such as quartz, is characterized by a series of elliptical reflective regions, their multiple axes oriented parallel, and two It is inserted into each position that can be indicated in the dimension (X-Y). For each grid-like layout of elliptical reflective areas on plate 135, the dimensions of the associated ellipse vary incrementally. Therefore, for the reflection ellipses of the regions 136 and 136' at the beginning and end of the first row, respectively, the regions become progressively smaller and the regions of the next adjacent row,
In the beginning and end regions 137 and 137', respectively, the reflection ellipses continue their progressive reduction, in the third column the progression continues to reduce from region 138 to 138', and in the last column , and further reduces from 139 to the smallest 139'. The support for the indicated displacement of the plate 135 is
It is understood that it is placed on its reflective side in relation to an inclined surface with respect to the laser output beam straight line 12', the slope being such that the center of the particular ellipse is preferably aligned with the straight line 12'.
2', the major axis of each ellipse is at 45° to the straight line 12',
At the same time, when the center of a particular ellipse is indicated to intersect the straight line 12', the minor axis of each ellipse is at 90° with the straight line 12', and the major/minor axis span is √2:
It is 1. This preferred relationship means that for each ellipse-indicated position, the laser beam reflection 12 is straight line 1
2', and determine that this reflection results in a circle with a diameter equal to the minor axis span of the ellipse involved. The X-Y coordinate drive system 140 and microprocessor 141a are implemented as described in FIGS. 6 and 7, and the optically readable grid lines (between reflection ellipses) on plate 135 are precisely In order to ensure accurate position adjustment, a pair of photoelectric elements 141-1
41' and 142-142' and are centered on axis 12' before firing the next laser pulse.

The automated running of the apparatus of FIG. 21, in a complete quadratic coordinate program of the indicator 135, covers the entire circular corneal area to be operated on, with increasing density as a function of increasing radius from the optical axis of the eye. It can be seen that the maximum density of removal energy is transferred to the central part of . Curvature changes are therefore the hallmark of myopia correction.

The embodiment of FIGS. 23 and 24 corresponds to FIGS. 8 and 9, so that a pattern distributed around the periphery of the reflective ellipse is on the index disk or disk 150, and the plate 150 is It is transparent and made of quartz. Preferably, the centers of all ellipses lie on one geometric circle around the index disc 150', which is aligned with the laser axis 12 and the (reflected) projection axis 12 to the eye. ' is oriented to bisect a right-angled relationship, axis 12 is aligned with the optical axis of eye 11, and preferably the long axis of each ellipse is oriented radially to the index center of plate 15. oriented and also all major/minor axis relationships are √2:1. Automated running of the rotatably indexed device of FIGS. 23/24 can produce the same corneal ablation result as the orthogonally indexed device of FIGS. 21/22, the result being again myopic. This is a correction.

FIG. 25, partially shown, shows another circular reflector plate 162 (in place of plate 150 of FIG. 24), and programming in the microprocessor for rotation direction and laser pulse generation is shown in FIG.
The curvature of the human cornea shown in the figure provides hyperopic correction. Each reflective ellipse in FIG. 25 has an elliptic ring portion on the outer periphery of a constant length that is continuous at a certain angular interval, and the continuous range is from the smallest elliptical ring portion 163' at the indicated position 163 to the indicated position 165. up to the maximum elliptic annular portion 165'. In other words, the continuation of the reflective ellipse in FIG.
62 represents an annular irradiation of constant outer diameter and varying inner diameter during one step rotation, representing the maximum ablation depth of the cornea at the outer diameter and progressively decreasing ablation depth with decreasing radius with respect to the optical axis of the eye 11 be done. All ellipsoids have a major axis to minor axis ratio of √2:1, taking into account the 45° angle of incidence of the laser beam on the designated elliptical reflector.

The arrangement in Figure 26 is similar to that in Figure 15 by applying a chiseled correction to the cornea to achieve the required final curvature Fresnel-type distribution, with reference also to Figures 12 and 13. , either hyperopic correction or myopic correction is possible. In order to avoid too deep a removal depth, the final reduced curved surface is defined by reference numeral 70, as indicated by reference numeral 31 in FIG. 4 (dotted line 71 in FIG. 13). The curved surface 71 is obtained in steps 72-73-74.

As shown in FIG. 26, transparent plate 175 acts as a replacement for disk 150 in FIG.
A series of reflecting ellipsoids is provided with stepwise transitions at angular intervals, the beginning of which is at position 1.
Largest and thickest elliptical portion 17 at 76′
6, and moving clockwise, the size and thickness of the next elliptic ring portion decreases slightly based on the inner limiting elliptical portion 177 having a constant size. Vertical section of the stage 72-7
3-74 (FIG. 13), a reflective ellipse based on the same inner limiting ellipse 177 is arranged within a first 120° angular sector of the disk 175; These have an outer elliptical edge that tapers off to a final smallest elliptical annulus (not shown). And the microprocessor 57 (Fig. 8)
is operative to control the positioning of the laser pulse shot using a predetermined arrangement of elliptical reflectors in the first sector as obtained by removing the curved surface 71 within the outer annular portion 72. Needless to say. A similar continuation of the reflective ellipsoid includes a curved section 7 within the intermediate annular section 73.
1' of the second disk 175.
Needless to say, it can be similarly provided on a 120° sector (not shown) so that it can be pointed to. Curved portion 71″
is formed in the inner circular region 74 by means of a predetermined laser shot irradiation on the irradiation axis 12' through a succession effective in indicating a progressively smaller elliptical region. The formation of the curved portion 71″ is as follows:
Starting at the oval portion of the largest minor axis span (not shown, but equal to the diameter of the central circular region 74), position 1 is adjacent to the first sector position 176'.
It decreases during the third 120 degree sector towards the smallest reflective ellipse 178 at 78'.

In the situation where one rotation of the disk 175 delivers a suitably defined pulsed laser onto the irradiation axis 12', the Fresnel step 7 is
Form 2-73-74. It should be noted that the use of high-precision optical annulation technology and metal deposition technology, which are effective in microcircuit technology, is one of the key factors in forming the gradualness of all annular partial components of all Fresnel type removal patterns.
Needless to say, this is helpful in driving multiple disks (not shown) in stages. In order to create a reflective ellipse pattern to achieve this result,
Figure 27 schematically shows the direction of dimensional change on the minor axis side of all complex reflective ellipses for the correction of myopia, and Figure 28 similarly shows the direction of dimensional change on the minor axis side of all complex reflective ellipses for the correction of hyperopia. It schematically shows the direction of dimensional change on the short axis side of the reflective ellipse.

In FIG. 27, the 360° range of a given circular disk (which can be used in place of the disk 150 in FIG. 23) is divided into a desired number n.
By dividing into indicative steps at intervals of 360°/n and by marking the vertical axis (e.g. vertical line 20) for each increasing distribution on the azimuth, complex multiples at each indicated position can be (e.g., a-b-c-d- at the position of line 120)
e) is obtained at 5 locations. The result related to FIG. 27 is a reduction in myopia since all the outer diameters (regions 72, 73, 74) change while the inner diameter remains constant. On the other hand, the results related to FIG.
3', 74') change, while the outer diameter remains constant and the intersection point a'-b'-c'-d'-e'-f'
This will reduce farsightedness.

As mentioned above, laser irradiation via positioned reflective areas is primarily associated with spherical curvature correction for treating hyperopia or myopia. However, it is clear that similar principles can be applied to astigmatism correction. In this case, the pattern of the progressive pointing reflective areas is a rectangle whose width gradually changes, and is formed symmetrically on opposite sides of the central extension axis of the rectangular pattern that is narrowest in the advancing direction. The drawing in FIG. 16 is designed to explain the pattern generation as described above.
The stepwise movable elongated plate 80 is a transparent plate (such as a quartz plate), and the serial parts from rectangles 81 to 81' are for reflection, and between the center lines indicating from one center line 82 to the next. the intervals are equal. Furthermore, the laser beam axis 12' (FIG. 15) is directed at the intersection of the central straight line 86 and each indicated position. The long plate 80 is a guide ring 84 (Fig. 15)
When supported on the inclined plate, also illustrated as disk 150 in FIG. It will represent the range. However, the desired cumulative removal may be accomplished in some or all preselected angular directions by incorporating appropriate angular correction elements into the microprocessor. Angle correction is a simple triangulation of azimuthal angles.

The use of the above-mentioned reflections according to the present invention is such that the individual patterns of reflections
2'), and the reflective pattern is placed, formed or otherwise placed on a transparent plate (such as quartz). A portion of a given laser beam output is not reflected and travels further straight approximately on axis 12'. Since this straight energy is not used for treatment, it may be trapped and dispersed by appropriate means (not shown).

[Brief explanation of drawings]

1 is a perspective view showing the general arrangement of the operating elements of the invention; FIG. 2 is a schematic sectional view showing the eyeball holding means used in the device of FIG. 1; FIGS. FIG. 5 is a schematic diagram showing the state in which the cornea is incised and carved using the apparatus shown in FIG. 1 in order to correct myopia, and FIG. 6 is a schematic diagram showing the configuration of another embodiment of the present invention. Fig. 7 is an index mask used in the embodiment of Fig. 6, Fig. 8 is a schematic diagram embodying Fig. 6, and Fig. 9 is a cutout of the indicator mask used in the embodiment of Fig. 8. , FIGS. 10 and 11 are schematic diagrams illustrating the use of the invention to correct hyperopic conditions, and FIGS. 12, 13 and 14 show Fresnel-type optical correction contours on the anterior surface of the cornea. FIG. 15 and FIG. 16 are schematic diagrams each showing an apparatus and features of an embodiment for astigmatism correction, and FIGS. 17 and 18 are schematic diagrams showing an embodiment of corneal transplantation according to the present invention. Schematic diagrams, FIGS. 19 and 20 are schematic diagrams showing other embodiments different from the embodiments in FIGS. 15 and 16, and FIGS. Schematic diagrams showing other embodiments corresponding to Figures 11 and 14, respectively;
FIGS. 27 and 28 are graphs showing a principle model of a reflecting mirror. DESCRIPTION OF SYMBOLS 10... Clamping means, 11... Eye, 12... Downward bent part, 12'... Central axis line, 13... Fixed laser device, 14... Zoom lens device, 15...
Reversible motor, 16... Cabinet, 17... Head fixing means, 18... Eyeball holding means, 20... Optical fixing means, 21... Gazing axis, 23... Converging axial end wall, 24... Side connection port, 25... Flange means, 2
8...Minimum diameter, 29...Maximum diameter (external boundary), 3
0... Outer surface (curve representing the surface), 31... Broken line (representing the final curvature), 35... Mask plate, 37,
37'...Opening, 40...X-Y coordinate drive system, 41...
Microprocessor, 41, 41'...photoelectric element,
42, 42'...photoelectric element, 43, 43'...grid line,
44, 44'... Grid line, 45... Synchronization line, 50
...Mask disk, 51... Maximum opening, 52... Minimum opening, 53... Radial direction mark, 54... Annular ring, 5
5... Drive device, 56... Rotation drive signal generator, 55
-56... Rotation drive system, 57... Microprocessor, 58... Synchronization line, 59... Photoelectric element, 60...
Cornea, 61...New contour, 62...Disk, 63...Angle mark, 63'...Minimum annular mask area, 64...
Next mark, 64'...slightly thick annular mask,
65'... Maximum annular opening, 65... Angular position, 70...
External boundary line, 71...dotted chain line (continuous curve shown by), 72...outer annular part, 73... intermediate annular part,
74... Inner annular portion (Fresnel cut), 75... Rotating mask disc, 76... Annular mask, 78... Minimum opening, 80... Long plate, 81... Maximum opening, 81'... Minimum opening, 82... Mark, 83... Guidance means, 84...
Ring, 85... Manual operation means, 87... Fixed instruction mark, 88... Lateral drive signal generator, 89... Microprocessor, 90... Photoelectric element, 95... Recess, 96... Implantation part, 97... Final contour, 100... Slot width driving means, 101, 102... side plate, 10
4... Annular base, 105... Cylindrical zoom lens device, 107... Drive device, 108... Rim, 135...
Transparent plate, 140...X-Y coordinate drive system, 141a...
Microprocessor, 141-141'...Photoelectric element, 142-142'...Photoelectric element, 150...Indicator disk, 150'...Indicator disk, 162...Reflector, 1
63'...Minimum elliptical ring part, 163, 165...Indicated position, 165'...Maximum elliptical ring part, 175...Transparent plate, 176...Maximum elliptical ring part, 176'...Position,
177...Inner ellipse, 178...Minimum reflection ellipse, 17
8'...Position.

Claims (1)

[Scope of Claims] 1. An engraving device for performing curvature correction surgery on the anterior surface of the cornea of an eye, comprising laser means for generating an output beam in the ultraviolet region of the electromagnetic spectrum, and a variable cross-sectional area of the beam irradiated on the cornea. controllable means for limiting the laser spot projection to a laser spot projection, the area change covering at least an area including the maximum curvature modification area to be removed and being symmetrical with respect to a beam projection axis coinciding with the optical axis of the eye; the intensity is limited to remove a fraction of a predetermined maximum removal depth of the stromal area of the cornea in a unit time;
Said engraving device, comprising control means connected to said laser means and said controllable means, said control means being able to relate the laser beam irradiation at the cornea to a change in the cross-sectional area of said beam so as to produce a diopter change in the cornea. 2. In the engraving device set forth in claim 1,
The control means is further connected to the laser means and the controllable means and is associated with laser beam irradiation at the cornea to effect a beam cross-section change in an outer annular region adjacent the curvature modification region of diopter changes. characterized by producing a stepwise radial outer change from (a) the substrate removal depth at the diopter change boundary to (b) substantially zero depth at the outer limit of said annular region. engraving equipment. 3. In a sculpting device for performing ophthalmic surgery that achieves volumetric removal of tissue within the optically functional area of the cornea by selective removal of the anterior surface of the cornea of a patient's eye into the stroma, on the optical axis. laser means for generating an output beam in the ultraviolet region of the electromagnetic spectrum; and optical means on the optical axis including a zoom lens having zoom drive means for variably setting the cross-sectional area of the beam spot on the cornea. the area change of said spot is within the maximum area to be ablated and is symmetrical with respect to the beam projection axis which coincides with the optical axis of the eye, and the laser beam projection intensity is within the maximum area to be removed and is symmetrical with respect to the beam projection axis The laser means and the zoom driving means are controlled so that the cumulative time of laser beam irradiation onto the cornea causes a diopter reduction change in the cornea. As related to the limited spot area changes that occur,
An engraving device as described above having programmable means with control connections for alignment. 4. In the engraving device set forth in claim 3,
The zoom lens is variable to convert the output beam into a limited circular cross-sectional area that changes in response to changes in the settings of the beam driving means, whereby a diopter reduction change results in myopia correction. An engraving device featuring: 5. In the engraving device set forth in claim 3,
The zoom lens has a variable property that converts the output beam into a restricted straight line extending through the optical axis, the straight line having a width that varies in response to changes in the settings of the zoom drive means; Therefore, the engraving device is characterized in that the diopter reduction change corrects astigmatism. 6 In the engraving device set forth in claim 3,
The zoom lens has a variable property that converts the output beam into a restricted straight line extending through the optical axis, the straight line having a width that varies in response to changes in the settings of the zoom drive means; Thus, a diopter reduction change results in an astigmatism correction, and the zoom lens has an optical axis and is mounted for selective global rotation about the optical axis, whereby the angular orientation of the line is An engraving device characterized in that it is configured according to that of a required astigmatism correction. 7. An engraving device for curvature correction surgery on the anterior surface of the cornea of an eye, comprising laser means for generating an output beam in the ultraviolet region of the electromagnetic spectrum, and reflecting said beam to variably irradiate the area of said beam on the cornea. and a reflecting means for limiting the
a driving means for changing the reflective area, the reflective area changing range includes at least the maximum curvature modification area to be removed, is symmetrical with respect to the beam irradiation axis coinciding with the optical axis of the eye, and the beam spot irradiation intensity is limited to ablating a fraction of a predetermined maximum ablation depth of the stromal region of the cornea in a unit time; An engraving device as described above, comprising means including a microprocessor with a control connection for aligning the laser beam irradiation at the cornea in a manner related to changes in the reflected spot area. 8. In the engraving device set forth in claim 7,
The reflecting means operates to illuminate the cornea with a central circular area and a plurality of large areas of the same shape, each of the irradiated areas forming concentric circles, thereby ensuring that the diopter change results in myopia correction. Characteristic engraving device. 9 In the engraving device according to claim 7,
The reflecting means is operative to illuminate the cornea with a plurality of small areas of the same shape as the maximum area of curvature correction, the illuminated area being annular and characterized by a gradually varying inner diameter. An engraving device characterized in that the diopter change thereby corrects hyperopia. 10. In the engraving device of claim 9, the reflective area change range is larger than the maximum curvature modification region, thereby determining an outer ring of laser beam projection surrounding the maximum curvature modification region, and determining the outer ring of laser beam projection surrounding the maximum curvature modification region, The means also include an outer diameter of the outer ring;
The engraving device wherein the outer diameter change (i) begins substantially at the outer diameter of the curvature modification region and (ii) varies such that the outer diameter increases. 11. In the engraving device according to claim 7, the reflecting means operates to illuminate the cornea in a narrow rectangular area centered on the optical axis of the eye and extending to the maximum area, and includes a plurality of The reflecting means is further operative to irradiate the cornea over a uniformly large area, each irradiation area being rectangular and varying in width symmetrically with respect to the length of the narrow area; The engraving device is characterized in that the diopter change corrects astigmatism. 12. The engraving device according to claim 11, wherein the length direction of the irradiation area is variable. 13. The engraving device according to claim 7, wherein the reflecting means operates to irradiate the cornea with a plurality of small areas having the same shape as the maximum area,
The irradiation area has a circular annular shape, and the outer diameter is constant and the inner diameter changes up to a constant minimum inner diameter.
An engraving device characterized in that said diopter change results in myopia correction by means of an engraved Fresnel ring defined by said constant outer diameter and said constant minimum inner diameter. 14. The engraving device according to claim 7, wherein the reflecting means operates to irradiate the cornea with a plurality of small areas having the same shape as the maximum area,
Moreover, the irradiation area is circular and has a constant inner diameter and an outer diameter that varies halfway between the inner diameter and the outer diameter of the maximum area, so that the diopter change is different from the inner diameter. An engraving device characterized in that the engraving device provides hyperopia correction by means of an engraved Fresnel ring defined by the outer diameter. 15. In the engraving device according to claim 7, the reflecting means includes a transparent plate having a series of reflecting elements on its surface, the reflecting elements have a gradually changing area, and the reflecting elements are exposed to a laser beam. 1. An engraving device comprising microprocessor-controlled means for specifying sequential alignment with the optical axis of the engraving device. 16. The engraving device according to claim 15, wherein the reflective elements are arranged in a straight line at intervals. 17. The engraving device of claim 15, wherein the reflective elements are arranged in a spaced array around the axis of rotation. 18. The engraving device of claim 7, wherein the reflecting means comprises a variable aperture diaphragm, the diaphragm having a reflective side surface arranged to reflect the laser beam to a continuous annular region around the diaphragm aperture. A carving device characterized by 19 In the engraving device according to claim 7, the angle of incidence of the laser beam on the reflecting means is
45°, its reflection area has a long axis to short axis ratio of √2:1, and the laser beam is incident on the center of the ellipse at an angle of 45° with respect to the long axis. An engraving device. 20 An engraving device for surgically operating on the outer surface of the cornea of a patient's eye, comprising means for generating an output beam in the ultraviolet region of the electromagnetic spectrum and mask means for variably limiting the irradiated area of the beam on the cornea. and the masking means includes drive means for changing the masked area, the range of masking area change is within the maximum area to be removed and is symmetrical with respect to the beam projection axis coinciding with the optical axis of the eye. can be,
The beam spot projection intensity is limited to remove a fraction of a predetermined maximum removal amount of the corneal stromal area per unit time, and the masking means covers the cornea in a plurality of areas having the same shape as the maximum area. The irradiation area is a circular ring with a varying inner diameter, and the irradiation area further has a constant outer diameter for the area where the hyperopia correcting curvature change is to be caused. and said curvature change area is smaller than said maximum area, thereby limiting an annular area of laser beam projection outside said curvature change area, and said mask means further protects the cornea within said annular area. The laser means and the drive means are operated to irradiate a series of circular annular areas adjacent to the area of varying curvature and varying outer diameter, and the laser irradiation onto the cornea causes a hyperopia correcting diopter change to the cornea. means including a microprocessor with a control connection for aligning the masked spot area to be associated with changes in the masked spot area such that changes to adjacent non-irradiated corneal tissue occur with a smoothly surrounding ring; The above engraving device. 21 In a sculpting device for performing ophthalmic surgery that achieves volumetric removal of tissue within the optically functional area of the cornea by selective removal of the anterior surface of the cornea of a patient's eye by penetrating into the stroma, laser means for generating an output beam in the ultraviolet region of the electromagnetic spectrum; and optical means on the optical axis including a zoom lens having zoom drive means for variably setting the cross-sectional area of the beam spot on the cornea. the area change of said spot is within the maximum area to be ablated and is symmetrical with respect to the beam projection axis which coincides with the optical axis of the eye, and the laser beam projection intensity is within the maximum area to be removed and is symmetrical with respect to the beam projection axis The laser means and the zoom drive means are controlled such that the cumulative time of laser beam irradiation onto the cornea causes a diopter-reducing change in the cornea. An engraving device as described above, having means including a microprocessor with control connections for matching in relation to variations in the limited spot area. 22. The engraving device according to claim 21, wherein the zoom lens has a variability that changes the output beam to a limited circular cross-sectional area that changes in response to changes in the settings of the beam driving means, An engraving device characterized in that the diopter reduction change thereby corrects myopia. 23. The engraving device of claim 21, wherein the zoom lens has a variable property that converts the output beam into a restricted straight line extending through the optical axis, and the straight line is arranged in the direction of the zoom drive means. An engraving device characterized in that it has a width that changes in response to a change in setting, whereby a diopter reduction change results in an astigmatism correction. 24. The engraving device according to claim 21, wherein the zoom lens has a variable property that converts the output beam into a restricted straight line extending through the optical axis, and the straight line is arranged in the direction of the zoom drive means. The zoom lens has an optical axis and has a width that changes as the settings change, whereby a diopter reduction change results in an astigmatism correction. An engraving device, characterized in that it is attached, whereby the angular orientation of said straight line is set according to that of the required astigmatism correction. 25. In an ophthalmic surgical engraving device that achieves volumetric removal of tissue within the optically functional area of the cornea by selective removal of the anterior surface of the cornea of a patient's eye by penetrating into the stroma, laser means for producing an output beam in the ultraviolet region of the electromagnetic spectrum; and mask means for variably limiting the beam's irradiation cross-section on the cornea, the mask means being masked by the mask means. a drive means for changing the cross-sectional area of the mask, the change in mask area is within the area of the maximum area to be removed and is symmetrical about a beam projection axis coinciding with the optical axis of the eye;
The laser beam projection intensity is limited to remove a fraction of a predetermined maximum amount of corneal stroma per unit time, and the laser means and the driving means are directed onto the cornea. An engraving device as described above, comprising means including a microprocessor with a control connection for aligning the laser beam irradiation to be associated with a change in cross-sectional area resulting in a diopter change to the cornea. 26. The engraving device of claim 25, wherein said mask means is operative to illuminate the cornea with said widest rectangular area and a plurality of smaller width areas, whereby said diopter change is An engraving device characterized by correcting astigmatism. 27. The engraving device of claim 25, wherein said mask means is operative to illuminate the cornea with said widest rectangular area and a plurality of smaller width areas, whereby said diopter change is An engraving device that corrects astigmatism and is characterized in that the longitudinal direction of the region is variable. 28 In the engraving device according to claim 25, the mask means operates to irradiate the cornea in the maximum area and a plurality of small circular areas, and each irradiation area is circular and has an external shape. An engraving device characterized in that the inner diameter is constant and the inner diameter changes, whereby the diopter change results in hyperopia correction. 29 In the engraving device according to claim 25, the mask means operates to irradiate the cornea in the maximum area and a plurality of small circular areas, and each irradiation area is circular and has a constant irradiation area. an engraved Fresnel having an inner diameter of A carving device characterized by correcting myopia using a ring. 30. The engraving device according to claim 25, wherein the mask means operates to irradiate the cornea in the maximum area and a plurality of small circular areas, each of the irradiation areas having a circular annular shape, The outer diameter is constant and the inner diameter is gradually varied up to a constant minimum inner diameter such that the diopter change is due to a carved Fresnel ring limited by the constant outer diameter and the constant minimum inner diameter. An engraving device characterized in that it corrects hyperopia. 31. The engraving device of claim 25, wherein the mask means includes an opaque plate (a) transparent to the laser beam, and (b) provided with a series of windows of varying area; An engraving device characterized in that means controlled by the setter are connected to direct the sequential alignment of the windows with the laser beam axis. 32. The engraving device of claim 25, wherein the mask means includes an opaque plate (a) transparent to the laser beam, and (b) provided with a series of windows of varying area; An engraving device characterized in that means controlled by the setter is connected to instruct the windows to be sequentially aligned with the laser beam axis, the windows being aligned in a straight line at intervals. . 33. The engraving device of claim 25, wherein the mask means includes an opaque plate (a) transparent to the laser beam, and (b) provided with a series of windows of varying area; An engraving apparatus characterized in that means controlled by the setter are connected to direct the sequential alignment of the windows with the laser beam axis, the windows being arranged in a spaced circular arrangement. 34. The engraving device of claim 25, wherein said mask means is operative to illuminate the cornea with said largest area of a circle and a plurality of smaller areas of the same shape of a circle, thereby causing said diopter variation. An engraving device characterized by correcting myopia. 35. The engraving device of claim 25, wherein said mask means includes an opaque plate (a) transparent to the laser beam, and (b) provided with a series of windows of varying area, said mask means comprising said programmable plate having a series of windows of varying area. means connected to direct the sequential alignment of the windows with the laser beam axis. 36. The engraving apparatus of claim 25, wherein said mask means comprises an opaque plate (a) transparent to the laser beam, and (b) provided with a series of windows of varying area, said programmable means are connected to direct the sequential alignment of the windows with the laser beam axis, the windows being aligned in a straight line at intervals. 37. The engraving device of claim 25, wherein said mask means comprises an opaque plate (a) transparent to the laser beam, and (b) provided with a series of windows of varying area, said programmable means are connected to direct the sequential alignment of the windows with the laser beam axis, the windows being spaced apart and arranged in a circular pattern. 38 In a sculpting device for performing ophthalmic surgery that achieves volumetric removal of tissue within the optically functional area of the cornea by selective removal of the anterior surface of the cornea of a patient's eye by penetrating into the stroma, laser means for producing an output beam in the ultraviolet region of the electromagnetic spectrum; and mask means for variably limiting the beam's irradiation cross-section on the cornea, the mask means being masked by the mask means. a drive means for changing the cross-sectional area of the mask, the change in mask area is within the area of the maximum area to be removed and is symmetrical about a beam projection axis coinciding with the optical axis of the eye;
The laser beam projection intensity is limited to remove a fraction of a predetermined maximum amount of corneal stroma per unit time, and the laser means and the driving means are directed onto the cornea. An engraving device as described above, comprising programmable means with a control connection for aligning the laser beam irradiation to be associated with a change in cross-sectional area resulting in a diopter change to the cornea. 39. The engraving device of claim 38, wherein said mask means is operative to illuminate the cornea with said widest rectangular area and a plurality of smaller width areas, whereby said diopter change is An engraving device characterized by correcting astigmatism. 40. The engraving device of claim 38, wherein said mask means is operative to illuminate the cornea with said widest rectangular area and a plurality of smaller width areas, whereby said diopter change is An engraving device that corrects astigmatism and is characterized in that the longitudinal direction of the region is variable. 41. In the engraving device of claim 38, the mask means operates to irradiate the cornea in the maximum area and a plurality of small circular areas, and each irradiation area is circular and has an external shape. An engraving device characterized in that the inner diameter is constant and the inner diameter changes, whereby the diopter change results in hyperopia correction. 42. In the engraving device of claim 38, the mask means operates to irradiate the cornea with the maximum area and a plurality of small circular areas, and each irradiation area is circular and has a constant irradiation area. an engraved Fresnel having an inner diameter of A carving device characterized by correcting myopia using a ring. 43. The engraving device according to claim 38, wherein the mask means operates to irradiate the cornea in the maximum area and a plurality of small circular areas, each of the irradiation areas being circular and annular; The outer diameter is constant and the inner diameter is gradually varied up to a constant minimum inner diameter such that the diopter change is due to a carved Fresnel ring limited by the constant outer diameter and the constant minimum inner diameter. An engraving device characterized by correcting hyperopia. 44. The engraving device of claim 38, wherein the mask means includes an opaque plate (a) transparent to the laser beam, and (b) provided with a series of windows of varying area; An engraving device characterized in that means controlled by the setter are connected to direct the sequential alignment of the windows with the laser beam axis. 45. The engraving device of claim 38, wherein the mask means includes an opaque plate (a) transparent to the laser beam, and (b) provided with a series of windows of varying area; An engraving device characterized in that means controlled by the setter is connected to instruct the windows to be sequentially aligned with the laser beam axis, the windows being aligned in a straight line at intervals. . 46. The engraving device of claim 38, wherein the mask means includes an opaque plate (a) transparent to the laser beam, and (b) provided with a series of windows of varying area; An engraving apparatus characterized in that means controlled by the setter are connected to direct the sequential alignment of the windows with the laser beam axis, the windows being arranged in a spaced circular arrangement. 47. The engraving device of claim 38, wherein said mask means is operative to illuminate the cornea with said largest area of a circle and a plurality of smaller areas of the same shape of a circle, thereby causing said diopter variation. An engraving device characterized by correcting myopia. 48. The engraving apparatus of claim 38, wherein said mask means includes an opaque plate (a) transparent to a laser beam, and (b) provided with a series of windows of varying area, said programmable means connected to direct the sequential alignment of the windows with the laser beam axis. 49. The engraving apparatus of claim 38, wherein said mask means comprises an opaque plate (a) transparent to the laser beam, and (b) provided with a series of windows of varying area, said programmable means are connected to direct the sequential alignment of the windows with the laser beam axis, the windows being aligned in a straight line at intervals. 50. The engraving apparatus of claim 38, wherein said mask means comprises an opaque plate (a) transparent to a laser beam, and (b) provided with a series of windows of varying area, said programmable means are connected to direct the sequential alignment of the windows with the laser beam axis, the windows being spaced apart and arranged in a circular pattern. 51 In a sculpting device for performing ophthalmic surgery that achieves volumetric removal of tissue within the optically functional area of the cornea by selective removal of the anterior surface of the cornea of a patient's eye by penetrating into the stroma, optical means comprising laser means for generating an output beam in the ultraviolet region of the electromagnetic spectrum; and reflecting means for reflecting said beam on said optical axis and variably limiting the cross-sectional area of said beam irradiation on the cornea. , comprising drive means for changing its reflection area, said reflection area change being on a range that produces a reflected beam cross-sectional area within the maximum area to be removed, and adapted in line with the optical axis of the eye. is symmetrical about the beam projection axis,
the projected beam intensity is limited to remove a fraction of a predetermined maximum amount of corneal stroma per unit time, means including a microprocessor with a control connection for aligning the laser beam irradiation of the laser beam to be associated with a change in the reflected beam cross-section resulting in a diopter change to the cornea. 52 In the engraving device according to claim 51, the angle of incidence of the laser beam on the reflecting means is
45°, the reflection area is an ellipse with a ratio of major axis to minor axis of √2:1, and the laser beam is incident at the center of the ellipse at an angle of 45° with respect to the major axis. An engraving device featuring: 53. In the engraving device of claim 51, the reflecting means operates to irradiate the cornea in a narrow rectangular area that is centered on the optical axis of the beam and extends to the maximum area. , the reflecting means further operates to irradiate the cornea in a plurality of large areas of the same shape, each of the irradiation areas being rectangular and having a width that varies symmetrically with respect to the length direction of the narrow area; An engraving device characterized in that the diopter change thereby corrects astigmatism. 54. In the engraving device of claim 51, the reflecting means operates to irradiate the cornea in a narrow rectangular area that is centered on the optical axis of the beam and extends to the maximum area. , the reflecting means further operates to irradiate the cornea in a plurality of large areas of the same shape, each of the irradiation areas being rectangular and having a width that varies symmetrically with respect to the length direction of the narrow area; Thereby, the engraving device is characterized in that the diopter change corrects astigmatism, and the longitudinal direction of the region is variable. 55. The engraving device according to claim 51, wherein the reflecting means operates to irradiate the cornea with a plurality of small areas having the same shape as the maximum area,
Furthermore, each of the irradiation areas is circular, with a constant outer diameter and a constant inner diameter that varies up to a constant minimum inner diameter, so that the diopter change is equal to the constant outer diameter and the constant minimum inner diameter. An engraving device characterized in that it is a farsightedness correction by means of a engraved Fresnel ring which is thus limited. 56. The engraving device according to claim 51, wherein the reflecting means operates to irradiate the cornea with a plurality of small areas having the same shape as the maximum area,
Moreover, each of the irradiation areas is circular and has a constant inner diameter and an outer diameter that varies halfway between the inner diameter and the outer diameter of the maximum area, so that the diopter change is caused by the diopter change in the inner diameter. and an engraving device for myopia correction by means of an engraved Fresnel ring defined by said outer diameter. 57. The engraving device according to claim 51, wherein the reflecting means includes a transparent plate having a series of reflective elements on its surface, the reflective elements gradually changing in area, and which are controlled by the microprocessor. The engraving apparatus is characterized in that the means for aligning the reflective elements is connected to designate sequential alignment of each reflective element with the optical axis of the laser beam. 58. The engraving device according to claim 51, wherein the reflecting means includes a transparent plate having a series of reflective elements on its surface, the reflective elements gradually changing in area, and which are controlled by the microprocessor. means connected to designate each reflective element to be sequentially aligned with the optical axis of the laser beam, the reflective elements being spaced apart and aligned in a straight line. Device. 59. The engraving device of claim 51, wherein the reflecting means includes a transparent plate having a series of reflective elements on its surface, the reflective elements gradually changing in area, and which are controlled by the microprocessor. means are connected to designate each reflective element to be sequentially aligned with the optical axis of the laser beam, and wherein the reflective elements are aligned at intervals about an axis of rotation. engraving device. 60. The engraving device of claim 51, wherein the reflecting means comprises a variable aperture diaphragm, the diaphragm having a reflective side surface arranged to reflect the laser beam to a continuous annular region around the diaphragm aperture. A carving device characterized by 61. The engraving device of claim 51, wherein the reflecting means is operative to illuminate the cornea with a concentric central circular area and a plurality of isomorphic large areas, whereby the diopter change is An engraving device characterized in that it corrects myopia. 62. The engraving device according to claim 51, wherein the reflecting means operates to irradiate the cornea in a maximum area and a plurality of small areas of the same shape, each of the irradiation areas being a ring, An engraving device characterized in that the inner diameter varies within the region, whereby said diopter variation is a hyperopic correction. 63 In a carving device for performing ophthalmic surgery that achieves volumetric removal of tissue within the optically functional area of the cornea by selective removal of the anterior surface of the cornea of a patient's eye by penetrating into the stroma, optical means comprising laser means for generating an output beam in the ultraviolet region of the electromagnetic spectrum; and reflecting means for reflecting said beam on said optical axis and variably limiting the cross-sectional area of said beam irradiation on the cornea. , comprising drive means for changing its reflection area, said reflection area change being on a range that produces a reflected beam cross-sectional area within the maximum area to be removed, and adapted in line with the optical axis of the eye. is symmetrical about the beam projection axis,
The projected beam intensity is limited to remove a fraction of a predetermined maximum removal amount of corneal stroma per unit time, and the laser means and the driving means are connected to the cornea. and programmable means with a control connection for aligning the laser beam irradiation to be associated with a change in the reflected beam cross-section resulting in a diopter change to the cornea. 64. In the engraving device of claim 63, the reflecting means operates to irradiate the cornea in a narrow rectangular area that is centered on the optical axis of the beam and extends to the maximum area. , the reflecting means further operates to irradiate the cornea in a plurality of large areas of the same shape, each of the irradiation areas being rectangular and having a width that varies symmetrically with respect to the length direction of the narrow area; An engraving device characterized in that the diopter change thereby corrects astigmatism. 65. In the engraving device of claim 63, the reflecting means operates to irradiate the cornea in a narrow rectangular area that is centered on the optical axis of the beam and extends to the maximum area. , the reflecting means further operates to irradiate the cornea in a plurality of large areas of the same shape, each of the irradiation areas being rectangular and having a width that varies symmetrically with respect to the length direction of the narrow area; Thereby, the engraving device is characterized in that the diopter change corrects astigmatism, and the longitudinal direction of the region is variable. 66. The engraving device according to claim 63, wherein the reflecting means operates to irradiate the cornea with a plurality of small areas having the same shape as the maximum area,
Furthermore, each of the irradiation areas is circular, with a constant outer diameter and a constant inner diameter that varies up to a constant minimum inner diameter, so that the diopter change is equal to the constant outer diameter and the constant minimum inner diameter. An engraving device characterized in that it is a farsightedness correction by means of a engraved Fresnel ring which is thus limited. 67. The engraving device according to claim 63, wherein the reflecting means operates to illuminate the cornea with a plurality of small areas having the same shape as the maximum area,
Moreover, each of the irradiation areas is circular and has a constant inner diameter and an outer diameter that varies halfway between the inner diameter and the outer diameter of the maximum area, so that the diopter change is caused by the diopter change in the inner diameter. and an engraving device for myopia correction by means of an engraved Fresnel ring defined by said outer diameter. 68. The engraving device according to claim 63, wherein the reflecting means includes a transparent plate having a series of reflecting elements on its surface, the reflecting elements gradually changing in area, and which are controlled by the microprocessor. The engraving apparatus is characterized in that the means for aligning the reflective elements is connected to designate sequential alignment of each reflective element with the optical axis of the laser beam. 69. The engraving device of claim 63, wherein the reflecting means includes a transparent plate having a series of reflective elements on its surface, the reflective elements gradually changing in area, and controlled by the microprocessor. means connected to designate each reflective element to be sequentially aligned with the optical axis of the laser beam, the reflective elements being spaced apart and aligned in a straight line. Device. 70 In the engraving device of claim 63, the reflecting means includes a transparent plate having a series of reflective elements on its surface, the reflective elements gradually changing in area, and controlled by the microprocessor. means are connected to designate each reflective element to be sequentially aligned with the optical axis of the laser beam, and wherein the reflective elements are aligned at intervals about an axis of rotation. engraving device. 71. The engraving device of claim 63, wherein the reflecting means comprises a variable aperture diaphragm, the diaphragm having a reflective side surface arranged to reflect the laser beam to a continuous annular region around the diaphragm aperture. A carving device characterized by 72. The engraving device of claim 63, wherein said reflecting means is operative to illuminate the cornea with a concentric central circular area and a plurality of isomorphic large areas, whereby said diopter change is An engraving device characterized in that it corrects myopia. 73. The engraving device of claim 63, wherein the reflecting means operates to irradiate the cornea in a maximum area and a plurality of small areas of the same shape, each irradiation area being a ring, An engraving device characterized in that the inner diameter varies within the region, whereby said diopter variation is a hyperopic correction.