JP2003015093A - Manufacturing method and manufacturing apparatus for ocular lens - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ocular lens, such as a contact lens, which can correct not only the abnormal refraction of a myopia and hyperopia but the wavefront aberrations including aberrations of higher order at need as well. SOLUTION: A temporary lens 20 is worn to a patient eye 16 and in this state the optical characteristics including the aberration information of the patient eye 16 are measured. The shape of the temporary lens 20 to be made into the desired contact lens is set in accordance with the resultant optical characteristics in such a manner that the necessary optical characteristics can be satisfied by correcting the aberrations at the patient eye 16 under the state of the temporary lens 20 which is held worn.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a technique relating to the design and manufacture of an ophthalmic lens such as a contact lens to be worn on a patient's eye having refractive errors such as myopia, hyperopia, astigmatism, and presbyopia, and particularly, the aberration in the patient's eye The present invention relates to an ophthalmic lens manufacturing method, a manufacturing apparatus, and the like that can provide an ophthalmic lens that can correct a refractive error including the above with high accuracy.

[0002]

2. Description of the Related Art Conventionally, as a kind of optical body for correcting visual acuity in a patient's eye having a refractive error, a contact lens which is worn on the front surface of the eyeball to correct the optical characteristic of the patient's eye is known. Then, when applying the contact lens to the patient's eye, generally, the refractive power of the naked eye of the patient's eye is measured by a subjective or objective eye refractive power measuring device, and based on the measurement result, the A suitable contact lens is determined by calculating the lens power of the contact lens that can satisfy the required eye refractive power.

However, the optical characteristics considered when selecting a contact lens by such a conventional method are generally only refractive errors in a narrow sense such as spherical lens power and cylindrical lens power, and the optical characteristics of the patient's eye are not always corrected. Therefore, it was hard to say that the best contact lens could be provided. Specifically, for example, even astigmatism in the patient's eye, there are those due to the shape distortion of the corneal surface and those due to the optical characteristics in the eyeball, in the case of the former corneal surface shape, While it is possible to effectively correct by the action of a tear lens formed by a contact lens of the type, there is a difference that it cannot be corrected by the tear lens when it is due to the latter intraocular optical characteristics, It is difficult to deal with these differences by clearly distinguishing them by the conventional contact lens selection method. Further, in the conventional contact lens selection method, aberration is hardly considered, and therefore, it is difficult to design a contact lens in consideration of sharpness, which is the quality of appearance with respect to the optical characteristics of the patient's eye, Even if it is possible to correct visual acuity for myopia, hyperopia, etc., there is a problem that it is difficult to stably realize the sharpness of the visual field.

In addition, Japanese Patent Publication No. 9-510800 discloses a method of designing a contact lens in consideration of a condition in which a preformed product of the contact lens is worn on the patient's eye. Merely discloses a technique of actually measuring a stable position of a contact lens on a patient's eye and forming a correction optical region with the obtained stable position as an optical center. It does not provide any solution to the problem of optical correction of astigmatism and aberrations.

[0005]

Here, the present invention has been made in the background of the above circumstances, and the problem to be solved is to correct the visual acuity of a patient's eye having a refractive error,
It is an object of the present invention to provide a novel manufacturing method, manufacturing apparatus, and designing method for an ophthalmic lens, which can easily and highly accurately realize optical characteristics with reduced aberrations.

[0006]

Aspects of the present invention made to solve such problems will be described below. The constituent elements used in each of the following aspects can be used in any combination as much as possible. Further, the aspects and technical features of the present invention are not limited to those described below, but are described in the entire specification and the drawings, or the invention idea that can be understood by those skilled in the art from those descriptions. It should be understood that it is recognized based on this.

First, a feature of the present invention relating to a method for manufacturing an ophthalmic lens is that: a, the patient's eye is fitted with a temporary lens, the optical characteristics of the patient's eye are measured, and the patient's eye containing aberration information is measured. A measurement step of obtaining optical information of the eye, and b necessary for correcting the aberration in the patient's eye with the provisional lens worn to realize the optical characteristics required for the patient's eye. Based on the lens shape correction information obtained in the measurement step, the lens shape correction information regarding the shape of the temporary lens is obtained based on the optical information obtained in the measurement step; And a lens processing step of forming an ophthalmic lens adapted to the patient's eye by processing a processing lens made of another lens formed of the same material as the temporary lens. There is the law.

A feature of the present invention relating to an apparatus for producing an ophthalmic lens is that the optical characteristics of the patient's eye are measured while the patient's eye is fitted with a temporary lens, and the patient's eye containing aberration information is measured. Measuring means for obtaining optical information of the eye, and e are required to correct the aberration in the patient's eye with the provisional lens worn and to realize the optical characteristics required for the patient's eye. Shape calculation means for obtaining lens shape correction information regarding the shape of the temporary lens based on the optical information obtained by the measuring means, and f based on the lens shape correction information obtained by the shape calculation means And a lens processing means for forming an ophthalmic lens having a shape suitable for the patient's eye by processing a processing lens made of another lens formed of the same material as the temporary lens. In apparatus for manufacturing ophthalmic lenses.

Further, a feature of the present invention relating to a method for designing an ophthalmic lens is that the optical characteristic of the patient's eye is measured with the provisional lens worn on the patient's eye, and the patient's eye including aberration information is measured. Necessary to obtain the optical information of the patient's eye and correct the aberration in the patient's eye under the condition where the temporary lens is worn based on the optical information, and to realize the optical characteristics required for the patient's eye. The ophthalmic lens design method determines the shape of the temporary lens.

In the present invention relating to the manufacturing method, manufacturing apparatus and designing method for such an ophthalmic lens,
Since the optical characteristics of the patient's eye are measured under the condition that the temporary lens corresponding to the ophthalmic lens is actually worn on the patient's eye, the optical characteristics of the patient's eye itself and the optical characteristics of the ophthalmic lens itself are distinguished from each other. It is possible to measure the optical characteristics of the patient's eye wearing the ophthalmic lens as one optical body without doing so, and thereby, for example, a tear lens at the boundary between the ophthalmic lens and the patient's eye. It is possible to obtain the optical information of the patient's eye wearing the ophthalmic lens by not only distinguishing but also considering the optical influences of 1.

Moreover, by measuring the optical characteristics of the patient's eye with the eye lens worn, the aberration information of the patient's eye with the eye lens worn can be easily and accurately obtained. You can do it.

Therefore, by using the optical information including the aberration information of the patient's eye obtained in this way, it is possible to function integrally with the patient's eye in the worn state to exhibit the desired optical characteristics. It is possible to easily obtain the shape of such an ophthalmic lens, and in the ophthalmic lens having the shape thus obtained, the target optical characteristics are small for the patient's eye under the wearing condition. The aberration can be applied with high accuracy.

In the present invention, the optical characteristics measured with respect to the patient's eye to which a temporary lens is worn include aberrations, the visual axis, the focal axis, the outer diameter of the cornea, and the astigmatic main meridian line according to each individual patient. The optical characteristics to be considered are appropriately selected from the direction, spherical eye refractive power, cylindrical eye refractive power, and the like. Here, the aberration targeted by the present invention includes not only defocus which means myopia and hyperopia but also eye position abnormality targeted for prism correction, and the like, in addition to or instead of such low-order aberration, Higher-order aberrations that cause blurring or distortion to reduce visual clarity can also be targeted.

The spherical eye refractive power, the cylindrical eye refractive power, the astigmatic main meridian direction, etc. of the patient's eye are, for example, as disclosed in JP-A-10-118.
By using the objective type eye refractive power measuring device such as a well-known autorefractometer described in Japanese Patent Publication No. 024, etc., the phase difference between the measuring light projected on the patient's eye and the reflected light on the fundus, etc. It is possible to measure based on
The visual axis, the focal axis, the outer diameter of the cornea, etc. can be measured by, for example, an autorefractometer, an autorefkeratometer, an optometer, etc., but a patient wearing a temporary lens using a CCD image sensor or visually It is also possible to measure by observing the eyes. Furthermore, when measuring the aberration of the patient's eye, it is difficult to adopt the aberration measurement method based on the topography of the cornea surface because a temporary lens is worn on the front surface, but for example, a psychophysical method that is a subjective measurement method. Various known methods such as means and objective measurement methods can be adopted, and in particular, a Hartmann-Shack wavefront detector (HSWS) based on the known Shack-Hartmann method and an improved Rochester HSW.
S, or it is desirable to measure using an eye refraction characteristic measuring device or the like described in Japanese Patent Laid-Open No. 2001-393, and by using such a device, the eye refracting power as well as low to high It is also possible to measure up to the next aberration together.

Furthermore, in the present invention, when the optical information of the patient's eye obtained by the measurement is used to determine the shape of the provisional lens required to impart the desired optical characteristics to the patient's eye. , For example, on the basis of the optical characteristics of the patient's eye obtained by measurement, obtain the measured distribution data of the refractive power of the patient's eye wearing the temporary lens over the entire optical region of the temporary lens, Based on the difference between the measured distribution data of and the target distribution data of the refractive power of the patient's eye required to achieve the desired optical characteristics, the required correction amount of the refractive power is applied to the entire optical area of the temporary lens. Calculated as distribution data over, further, from the distribution data of the necessary correction amount of the obtained refractive power, based on the known Snell's law,
The distribution data of the curvature change amount to be added to the temporary lens in order to realize the necessary correction of the refractive power is obtained, and the distribution data of the curvature change amount thus obtained and the known data or the measurement data are clarified. With the sum of the curvature distribution data of the provisional lens, it is possible to determine the shape of the ophthalmic lens that is required to impart the desired optical characteristics to the patient's eye.

Further, in the manufacturing method, manufacturing apparatus, and designing method of the ophthalmic lens according to the present invention, the shape required for imparting the desired optical characteristics to the patient's eye, obtained as described above. The ophthalmic lens provided with can be advantageously provided as, for example, a contact lens such as a hard contact lens, a soft contact lens, or a disposable type contact lens, or an artificial cornea. Further, when the shape of the ophthalmic lens required to impart the desired optical characteristics to the patient's eye is a non-rotating body having directionality with respect to the lens central axis, for example, in the case of contact lenses, conventionally As is known, a prism ballast structure with the center of gravity biased downward,
Positioning the ophthalmic lens in the circumferential direction when worn on the patient's eye, such as a dynamic stabilization structure in which the upper and lower edges of the lens outer surface are tapered, and a truncation structure in which the lower end of the lens is cut out in a substantially straight line in the horizontal direction A position stabilizing means for doing so can be appropriately adopted.

Further, in the present invention, particularly when a contact lens is targeted as an ophthalmic lens, a contact lens having a shape required for imparting desired optical characteristics has been conventionally known. It can also be formed by a molding method (cavity molding method), a race cut method (cutting and polishing method), a spin casting method (centrifugal casting method), etc., but is preferably thicker than the target ophthalmic lens. It is desirable to form a target ophthalmic lens by adopting a processing lens made of meat and performing a molding process by irradiating the processing lens with a laser beam.
This makes it possible to easily obtain an ophthalmic lens having a complicated curvature distribution that is not a simple spherical shape.

Here, as a laser used for processing, an excimer laser, a YAG laser, a semiconductor laser or the like can be used. Further, as the laser beam in the present invention, it is also possible to adopt a femtosecond laser or a very short pulse laser having a laser pulse interval of femtosecond or less, thereby, for example, an intermediate portion in the lens thickness direction. Focus the laser on
It is also possible to perform processing such as forming a lens surface by cutting the processing lens. The processing lens may be made of the same material as the temporary lens in order to make the optical conditions the same as the temporary lens worn when measuring the optical characteristics of the patient's eye. It is also effective to use a lens formed of the same material and shape as the lens. Particularly, by processing the temporary lens itself to make it an ophthalmic lens, it is possible to further improve and stabilize the accuracy. Can be done.

Furthermore, in the present invention, when the optical information of the patient's eye obtained by the measurement is used to determine the provisional lens shape required for imparting desired optical characteristics to the patient's eye, , The shape of the inner surface of the temporary lens is unchanged, and the lens shape correction information regarding the shape of the temporary lens required to realize the optical characteristics required for the patient's eye is used as the shape correction information of the outer surface of the temporary lens. It is desirable to ask. By fixedly setting the inner surface shape of the temporary lens in this way, it becomes possible to easily obtain the lens shape correction information for obtaining the target ophthalmic lens. In addition, in the case of ophthalmic lenses such as contact lenses, generally, the inner surface shape of the ophthalmic lens is set to a base curve corresponding to the corneal shape of the patient's eye to be worn, so only the outer surface shape of the processing lens is corrected. By doing so, the preset fitting characteristics to the patient's eye can be secured stably, and unexpected changes in the stable position of the temporary lens when worn on the patient's eye are avoided, and The effect of correcting the eye refractive power by the lens can be obtained more stably.

Particularly, in the case of correcting only the shape of the outer surface of the processing lens, the temporary lens is adopted as the processing lens, and the temporary lens is worn on the patient's eye,
It is also possible to process the temporary lens by irradiating the outer surface of the temporary lens with a laser beam to obtain a target ophthalmic lens. When laser processing the temporary lens in the wearing state as described above, for example, LASIK (la
ser in situ keratomileusis) and PRK (photorefract
A corneal surgery device equipped with an excimer laser irradiation device used for carrying out ive keratectomy can be preferably adopted, whereby the surface shape of the temporary lens under the wearing condition can be processed. Further, by using the femtosecond laser or the ultrashort pulse laser described above, the laser beam is projected from the surface side to the temporary lens that is worn on the patient's eye, and the intermediate portion in the thickness direction of the temporary lens. It is also possible to surface-process the temporary lens by cutting.

Further, when the outer surface of the processing lens is processed by the laser beam with the processing lens worn on the patient's eye, in the lens processing step, the processing lens is processed by irradiation of the laser beam. In parallel,
It is also possible to measure the optical characteristics of a patient's eye wearing the processing lens. Specifically, an optical system for measuring the optical characteristics of the patient's eye and a laser irradiation system for lens processing by laser beam irradiation are used together to measure the measurement light with respect to the patient's eye. It is possible to perform simultaneously a measurement operation of projecting a laser beam and measuring an optical characteristic, and a processing operation of irradiating a laser beam to process a processing lens alternately or continuously at a short time. In consideration of the optical characteristics of the patient's eye obtained by the measurement operation, it is possible to appropriately correct the processing amount of the processing lens by the irradiation of the laser beam.

Furthermore, as described above, by performing lens processing with a laser beam in a state where the processing lens is worn on the patient's eye, a soft type contact lens conventionally considered to be unsuitable for correction of astigmatism. Also, an artificial cornea, or a compound lens in which an artificial cornea is applied to the inner surface of a contact lens, etc., is advantageous as an ophthalmic lens that effectively has a function of correcting eye refractive power including correction of astigmatism together with a function of correcting aberration. And can be easily provided. In addition, in such an ophthalmic lens, a means for stabilizing the circumferential position with respect to the patient's eye will be employed as necessary.

Further, in the manufacturing method, manufacturing apparatus, and designing method of the ophthalmic lens according to the present invention, the processing lens is subjected to predetermined processing as described above to impart the desired optical characteristics to the patient's eye. After obtaining an ophthalmic lens having a shape required to do, in a state where the obtained ophthalmic lens is worn on the patient's eye, the optical characteristics of the patient's eye are measured to obtain the patient's eye. It is desirable to confirm whether the desired optical characteristics can be realized. More preferably, when such confirmation work reveals that the optical characteristics required for the patient's eye cannot be satisfied, the ophthalmic lens is used as a temporary lens and again according to the present invention as described above. , To measure the optical characteristics of the patient's eye with the ophthalmic lens as such a temporary lens worn, and to achieve the optical characteristics required for the patient's eye based on the obtained optical information. The shape of the temporary lens is reset and the ophthalmic lens is reprocessed in a corrective manner.

[0024]

Embodiments of the present invention will now be described in detail with reference to the drawings in order to more specifically clarify the present invention.

First, FIG. 1 is a block diagram showing the schematic structure of a contact lens manufacturing apparatus 10 having a structure according to the present invention. The contact lens manufacturing apparatus 10 of the present embodiment is configured to include an eye optical characteristic measuring apparatus 12 that measures optical characteristics of a patient's eye, and a lens processing laser apparatus 14 that shapes a contact lens by a laser beam. Based on the optical characteristic of the patient's eye determined by the eye optical characteristic measuring device 12, the lens processing laser device 14 operates so that the optical characteristic required for the patient's eye can be realized by being worn on the patient's eye. It is controlled to produce a desired contact lens.

Next, a method of manufacturing a contact lens suitable for a patient's eye using the contact lens manufacturing apparatus 10 will be described with reference to the flowchart shown in FIG. 1
A description of 0 will be added.

When the manufacturing of the contact lens is started, first, in steps S1 and S2, the basic information of the patient's eye is acquired and the optical characteristics required in the patient's eye are determined. That is, as shown in FIG. 3, basic information such as the radius of curvature and the outer diameter of the surface of the cornea 18 and the refractive power of the naked eye are acquired for the patient's eye 16 who is going to prescribe a contact lens. Note that such basic information can be obtained in accordance with a conventional contact lens compatibility test, and can be easily performed using, for example, a known autorefractometer, keratometer, or lensmeter. Alternatively, it is easy to provide the eye optical characteristic measuring device 10 with such a basic information measuring function according to, for example, a well-known objective examination method.

While considering the obtained basic information of the patient's eye 16, the contact lens is worn on the patient's eye 16 based on the living environment and wishes of the patient and the knowledge and judgment of a specialist such as an ophthalmologist. The target optical characteristics to be realized are determined, including whether or not they are appropriate. Specifically, for example, when the operating environment of the computer or the like is prioritized, the myopia state is aimed rather than the emmetropic state, when the driving environment of the vehicle is prioritized, the orthoscopic state is aimed, or the visual acuity of the patient's eye 16 is The optical characteristics required in the patient's eye 16 are determined such that the hyperopia state is aimed rather than the emmetropia in consideration of the accommodation function. At this stage, generally, it is not necessary to consider the required characteristics regarding aberrations, but for example, visual discrimination power for special colors is required, so aberrations for visible light in a specific wavelength range are suppressed as much as possible. When there are special circumstances such as wants, it is effective for the examiner to understand such circumstances.

Then, in step S3, the standard of the temporary contact lens as a temporary lens suitable for the patient's eye 16 is determined based on the above-mentioned basic information acquired about the patient's eye 16. According to the conventional prescription work for contact lenses, this work is performed so as to have the radius of curvature of the inner surface of the lens corresponding to the radius of curvature of the corneal surface of the patient's eye 16, that is, generally smaller than the radius of curvature of the corneal surface. By selecting the base curve of the temporary lens so as to have a spherical inner surface with a large radius of curvature, and by selecting the front curve of the surface of the temporary lens so as to have a lens power that corrects the refractive error of the patient's eye 16. Be seen. At that time, a spherical lens power for correcting myopia and hyperopia in the patient's eye 16 as well as a cylindrical lens power for correcting astigmatism may be set in the temporary lens, but the most important point should be given here. This is the selection of the base curve of the temporary lens and the selection of an appropriate temporary lens material. Since the spherical lens power and the cylindrical lens power can be changed, adjusted, and added in the subsequent process, particularly high accuracy is achieved. It is not necessary to perform the setting, and it is possible to make no setting regarding the lens power.

In this embodiment, when the lens power is changed in the subsequent step, the laser beam cutting process is employed in the present embodiment. Therefore, as a temporary lens, the thickness dimension is sufficient for strength after processing in the subsequent step. It is desirable to select a temporary lens having a sufficient wall thickness so that Specifically, for example, a provisional lens is prepared in advance that can cover a base curve, a center thickness, an outer diameter dimension, and a spherical lens power in a range that can be generally assumed with reference to past survey data and the like. It is possible to deal with it in advance. In that case, in order to correspond to high accuracy, for example, the base curve of the temporary lens is 6.0 mm to 10.0 mm.
In the range of 0.1 mm, and the center thickness is 0.0
Aligning every 0.05mm in the range of 5 to 1.00mm, and aligning the outer diameter dimension every 0.5mm in the range of 7.0 to 15.0mm.
Further, it is possible to arrange the spherical lens power in the range of −25.0 to +25.0 diopters every 0.5 diopters. Further, in order to improve the adaptability of the base curves, it is also effective to prepare those having different base curves set in the orthogonal radial directions.

Further, the shape of the temporary lens is generally a spherical shell shape having a circular outer peripheral surface which is a rotating body around the central axis, but other than this, for example, the positioning means in the circumferential direction on the patient's eye 16 is used. For the purpose of giving, for example, a temporary lens in which the center of curvature of the inner surface and the outer surface of the lens are deviated to set a certain prism ballast in advance, truncation in which the outer peripheral edge has an irregular shape such as an ellipse, or a dynamic stabilization structure is adopted. A temporary lens or the like can also be appropriately adopted. In addition,
Prism ballast, truncation, dynamic stabilization structure, etc. can be added to the finished contact lens by processing a spherical shell-shaped temporary lens that is a rotating body around the central axis with a laser beam, Of course it is possible.

Furthermore, in order to perform observation and measurement easily or with high accuracy, the provisional lens should have appropriate indices such as dots or lines only in specific areas or specific positions such as the entire surface of the lens surface or the outer peripheral portion. Can be added within a range that does not affect the visual optics or by an erasable method. For example, a circumferential line extending around the central axis of the temporary lens and a radial line extending in the radial direction can be provided. Indices such as a suitable number of dots, dots (points) at specific positions on the temporary lens, or lattice lines on the entire surface of the temporary lens may be used. It should be noted that such an index can be freely used because it is not necessary to consider the influence of visual optics when a temporary lens is used only for inspection and a separate lens is used as an ophthalmic lens. It becomes possible to set.

Then, in step S4, as shown in FIG. 4, a temporary lens 20 made of a specific material and shape satisfying the standard selected as described above is attached to the patient's eye 16. Then, in step S5, the temporary lens 20 is placed on the patient's eye 16 in a stable position and, as shown in FIG. The optical properties of patient eye 16 with 20 are measured.

Here, as shown in FIG. 1, the eye optical characteristic measuring device 12 has a measuring light irradiation optical system including a light source for projecting the measuring light 22 onto the patient's eye 16 and irradiating it onto the retina 24. 26, and a reflected light receiving optical system 28 including a light receiving element for detecting the reflected light of the measurement light 22 on the retina 24. The measurement light 22 emitted from the crystalline lens 32 to the retina 24 from the cornea 18 of the patient's eye 16 through the pupil 30 by the measurement light irradiation optical system 26 is converted into the retina 24.
Reflected by the lens 32, the pupil 30, and the cornea 1 again.
The reflected light is guided to the outside through 8 and is detected by the reflected light receiving optical system 28. Based on the distortion of the reflected light detected by the reflected light receiving optical system 28, the patient's eye 16 The arithmetic unit 34 calculates the refracting power and aberration in the.

Specifically, such an eye optical characteristic measuring device 12 is advantageously constituted by, for example, a Hartmann-Shack wavefront detector (HSWS). Since such a wavefront detector (HSWS) is a known technique, detailed description thereof will be omitted. However, the wavefront of monochromatic reflected light from the spot on the retina 24 of the patient's eye 16 is guided to a two-dimensional lenslet array.
This is a sample as an array of spot images, and based on the result of measuring the positional deviation of the spot image detected by such a two-dimensional small lens array with a CCD sensor,
The wavefront aberration including the high-order aberration in the patient's eye 16 is measured, and the aberration of the patient's eye can be objectively measured in an extremely short time. Moreover, in this wavefront detector, the index of refraction can also be measured by using an index, if necessary, by measuring the image formation of the fundus image from the reflected light. It is also possible to use it when acquiring the basic information of the patient's eye 16 in.

The eye optical characteristic measuring device 12 is provided with a data input / operation device 36 such as a keyboard and a mouse, and a display device such as a CRT for externally displaying the operating state of the device and the measurement result. 38 is provided,
Further, a storage device 40 such as a memory or a hard disk for storing the arithmetic processing program, the measurement result and the like as required is provided.

Further, in step S6, the processing data of the temporary lens 20 required to realize the desired optical characteristics in the patient's eye 16 is calculated using the eye optical characteristic measuring device 12. That is, the eye optical characteristic measuring device 12 inputs the desired optical characteristic of the patient's eye 16 from the data input / operation device 36 so that the arithmetic device 34 realizes the desired optical characteristic of the patient's eye 16. The outer surface shape of the contact lens required for the above is calculated. The arithmetic unit 34 is composed of a microcomputer, in which the measurement light receiving optical system 26 as described above is provided.
The eye-refractive-power calculator and the eye-aberration calculator that calculate the eye-refractive-power and the eye-aberration from the data obtained by It can be advantageously configured by installing an appropriate arithmetic processing program.

Here, the calculation of the outer surface shape of the contact lens necessary for imparting the desired optical characteristics to the patient's eye 16 is performed, for example, by the eye optical characteristic measuring device 12 in the above step S5. The target values of the eye refractive power and the eye aberration, which are the optical characteristics of the patient eye 16 wearing the provisional lens 20, which are the optical characteristics required in the patient eye 16 determined in step S2, are calculated. And the temporary lens 2 required to realize the difference between the optical characteristics as well as the difference between them.
The change amount of the outer surface shape of 0 is calculated by using a well-known formula based on Snell's law, and then the obtained temporary lens 20 is calculated.
Can be performed by adding the amount of change in the outer surface shape of the temporary lens 20 selected in step S3 and worn on the patient's eye 16.

Then, in the following step: S7, the corrected shape of the provisional lens 20 calculated in this way is given to the provisional lens 20 worn on the patient's eye 16 to be determined in the step: S2. , Patient eye 16
The temporary lens 20 that gives the optical characteristics required for the above can be realized, and the processing of the temporary lens 20 for that purpose is performed by using the lens processing laser device 14 in this embodiment as shown in FIG. Done using.

As the lens processing laser device 14, a corneal surgery device for ablating and shaping the cornea according to a conventionally known method as LASIK can be adopted, and it is described in, for example, Japanese Patent Application Laid-Open No. 9-266925. It is possible to realize the target shape of the temporary lens 20 obtained in step S6 with the temporary lens 20 still worn on the patient's eye 16 by using the above device or an appropriate commercially available device. .

More specifically, as the lens processing laser device 14, a device equipped with an excimer laser irradiation device is preferably adopted. For example, a reciprocating motion of a rectangular beam and a rotary motion of an irradiation part are combined. Laser beam irradiation from multiple directions to improve the setting flexibility and uniformity of the ablated portion, and to combine multiple types of circular beam and slit to achieve multiple types of linear or spot A laser beam irradiation shape can be selected to finely adjust the irradiation site.In addition, a transition zone is set at the peripheral edge of the laser beam to smooth the step generated at the boundary between the laser beam irradiation part and the non-irradiation part. It is possible to make it tilted, or improve the precision of fine adjustment of the focal point of ablation with a laser beam to submicron Such as those capable trace resection in position is employed in combination as appropriate.

Further, in such a lens processing laser device 14, the irradiation position of the laser beam, the number of laser irradiation pulses and the laser irradiation power are controlled by the computer, and it is obtained in step S6. By providing the desired shape data of the temporary lens 20, the operation is controlled so that such a shape of the temporary lens 20 can be realized.

Here, the cutting amount of the temporary lens 20 by the laser beam of the processing laser device 14 is, for example, the outer surface shape of the desired temporary lens 20 obtained in step S6 and the temporary lens 20 given in advance. It is given as three-dimensional information indicating the distribution state of the difference with the outer surface shape. Further, when calculating the three-dimensional information regarding the ablation amount, the minimum value of the difference in the outer surface shape of the target temporary lens 20 from the predetermined outer surface shape of the temporary lens 20 is set to be 0 or less. As a result, the desired outer surface shape of the temporary lens 20 can be realized only by cutting the outer surface of the worn temporary lens 20.
The maximum value of the difference in the outer surface shape of the target temporary lens 20 with respect to the outer surface shape of the temporary lens 20 given in advance is set so as not to exceed the excision allowance of the temporary lens 20, and the temporary lens 20 is practically used. Adjust to ensure the wall thickness. Further, as described above, the three-dimensional information on the ablation amount is obtained by directly obtaining the distribution from the difference between the desired outer surface shape of the temporary lens 20 and the predetermined outer surface shape of the temporary lens 20. Alternatively, for example, the optical region of the temporary lens 20 is divided into a plurality of regions with an appropriate shape such as a concentric circle shape, a strip shape, and a grid shape, and a desired curvature is approximated for each area. It is also possible to obtain the distribution data of the amount of excision by using the result of the statistical calculation.
In particular, by dividing the outer surface of the temporary lens 20 into a plurality of regions having an appropriate size like the latter, it is possible to set the surface shape of each region as a spherical surface or an aspherical surface that can be expressed by a mathematical expression. Beam actuation control can also be simplified.

As shown in FIG. 7, the contact lens 42 as an ophthalmic lens provided by the laser processing as described above has an optical shape with respect to the patient's eye 16. The objective optical characteristics are set, so that not only can refractive errors such as myopia and hyperopia be compensated, but also wavefront aberrations such as astigmatism or higher order aberrations can be compensated. Aberration can also be compensated,
It can be best fit to the patient's eye 16 to achieve a very high degree of visual acuity.

Further, in this embodiment, the patient's eye 16
Since the contact lens 42 worn on the cornea 18 is laser-processed and shaped to achieve a high degree of visual compensation or correction including aberrations, the patient's eye 16 including the cornea 18 can be realized. Since no external operation is applied, a high degree of safety can be achieved.

It should be noted that errors and mistakes may occur in the steps from the setting of the shape of the temporary lens in S5 to S7 to the addition of the shape by processing. However, such errors and mistakes may occur. It is effective to provide a feedback-like inspection step in order to avoid the resulting defect and more stably realize the desired visual compensation. One specific example is shown in FIG. This is illustrated by the corresponding flow chart.

That is, in the method of manufacturing a contact lens according to the flowchart shown in FIG. 8, after the contact lens 42 is formed in steps S1 to S7 according to the above-described method, a step S8 as an inspection step is performed.
In step S5, the optical characteristics of the patient's eye 16 with the formed contact lens 42 worn are described.
The measurement is performed in substantially the same manner as in step S9, and in the following step S9, it is determined whether the optical characteristics obtained in step S7 satisfy the desired optical characteristics set in step S2. If the patient's eye 16 wearing the formed contact lens 42 is within the permissible range of desired optical characteristics, it is determined that the contact lens has been normally manufactured, and the contact lens is manufactured. On the other hand, when the patient's eye 16 wearing the contact lens 42 is out of the allowable range of the desired optical characteristics, the contact lens 42 is reprocessed by repeating step S5 and subsequent steps. By doing so, the optical characteristics are corrected until the satisfactory optical characteristics are confirmed in step S8.

Although the embodiment of the present invention has been described in detail above, this is merely an example, and the present invention should not be construed to be limited to the specific description of the embodiment.

For example, in the above-described embodiment, the case where the refractive error such as myopia or hyperopia in the patient's eye 16 is corrected has been described, but the present invention can be applied to the case where such refractive error does not pose a problem. Therefore, it is possible to compensate only the wavefront aberration such as astigmatism. It should be noted that the present invention can be similarly applied to the case where high-order aberrations are not a problem, and accordingly, it is possible to compensate only the refractive error such as defocus.

Further, in the above-mentioned embodiment, the temporary lens 20 is laser-processed while it is still worn on the patient's eye 16. However, the temporary lens 20 is processed with the temporary lens 20 removed from the patient's eye 16, or the temporary lens 20 is processed. Temporary lens 2 worn on the eye 16
It is, of course, possible to manufacture the target contact lens 42 by processing another processing lens formed of the same base curve and the same material as that of 0 without wearing it on the patient's eye 16.

Although not listed one by one, the present invention is
The present invention can be carried out in a mode in which various changes, modifications, improvements, etc. are added based on the knowledge of those skilled in the art, and in addition, unless such a mode deviates from the spirit of the present invention,
It goes without saying that it is included within the scope of the present invention.

[0052]

As is apparent from the above description, according to the present invention, not only the refractive error such as myopia and hyperopia in the patient's eye but also wavefront aberration including higher-order aberrations can be enhanced at a high degree. It is possible to easily manufacture an ophthalmic lens such as a contact lens that can be compensated.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic structure of an embodiment of a contact lens manufacturing apparatus according to the present invention.

FIG. 2 is a flow chart for explaining an embodiment of a method for manufacturing a contact lens according to the present invention.

FIG. 3 is an explanatory diagram for explaining one manufacturing step in manufacturing a contact lens according to the flowchart shown in FIG.

FIG. 4 is an explanatory diagram for explaining another manufacturing step when manufacturing a contact lens according to the flowchart shown in FIG.

FIG. 5 is an explanatory diagram for explaining still another manufacturing step when manufacturing the contact lens according to the flowchart shown in FIG. 2.

FIG. 6 is an explanatory diagram for explaining still another manufacturing step when manufacturing a contact lens according to the flowchart shown in FIG. 2.

FIG. 7 is an explanatory diagram for explaining still another manufacturing step when manufacturing the contact lens according to the flowchart shown in FIG. 2.

FIG. 8 is a flowchart showing another embodiment of the method for manufacturing a contact lens according to the present invention.

[Explanation of symbols]

10 Contact lens manufacturing equipment 12 Eye optical characteristic measuring device 14 Laser equipment for lens processing 16 patient eye 18 cornea 20 Temporary lens 34 arithmetic unit 42 contact lenses

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) A61F 9/00 500 (72) Inventor Asaki Susaki 5-1, Takamoridai, Kasugai City, Aichi Prefecture 10 Stock Company F term in Menicon Research Institute (reference) 2H006 BC07 DA00 DA08 4E068 DA00 DB13

Claims (14)

[Claims] 1. A measuring step of measuring optical characteristics of the patient's eye to obtain optical information of the patient's eye including aberration information in a state in which the patient's eye is fitted with the temporary lens; In the measuring step, the lens shape correction information regarding the shape of the temporary lens required to correct the aberration in the patient's eye in the closed state and realize the optical characteristics required for the patient's eye is obtained. Processing a shape calculation step obtained based on optical information and a processing lens made of the temporary lens or another lens formed of the same material as the temporary lens based on the lens shape correction information obtained in the shape calculation step. And a lens processing step of forming an ophthalmic lens adapted to the patient's eye. 2. In the lens processing step, the ophthalmic lens is formed by irradiating a laser beam to the processing lens having a thickness larger than that of an intended ophthalmic lens to perform a molding process. Item 2. A method for manufacturing an ophthalmic lens according to Item 1. 3. The method of manufacturing an ophthalmic lens according to claim 2, wherein the laser beam has a laser pulse interval of femtosecond or less. 4. Lens shape correction information relating to the shape of the temporary lens, which is required in order to make the shape of the inner surface of the temporary lens invariable in the shape calculation step and realize the optical characteristics required for the patient's eye. 4. The method for manufacturing an ophthalmic lens according to claim 1, wherein is obtained as the shape correction information of the outer surface of the temporary lens. 5. In the lens processing step, the provisional lens is used as the processing lens, and the provisional lens is worn on the patient's eye, and the outer surface of the provisional lens is irradiated with a laser beam to produce the provisional lens. The method for manufacturing an ophthalmic lens according to claim 4, wherein the lens is processed. 6. After the lens processing step is completed, there is a confirmation step of measuring and confirming the optical characteristics of the patient's eye with the obtained ophthalmic lens worn on the patient's eye, and the confirmation is performed. In the step, when the optical characteristics of the patient's eye measured by wearing the ophthalmic lens do not satisfy the optical characteristics required for the patient's eye, the shape calculation is performed using the ophthalmic lens as the temporary lens. The method for manufacturing an ophthalmic lens according to claim 1, wherein the lens processing step is performed by using the ophthalmic lens as the processing lens while performing the step. 7. The optical characteristic of the patient's eye wearing the processing lens is measured in parallel with the processing of the processing lens by irradiation of the laser beam in the lens processing step. Manufacturing method of the above ophthalmic lens. 8. The method for manufacturing an ophthalmic lens according to claim 1, wherein the processing lens is one of a contact lens and an artificial cornea. 9. The ophthalmic lens according to claim 1, wherein the processing lens is provided with position stabilizing means for positioning in the circumferential direction in a state of being worn on the patient's eye. Production method. 10. A measuring means for measuring optical characteristics of the patient's eye to obtain optical information of the patient's eye including aberration information while the patient's eye is fitted with the temporary lens, and the temporary lens is mounted. The lens shape correction information regarding the shape of the temporary lens, which is necessary to correct the aberration in the patient's eye in the closed state and realize the optical characteristics required for the patient's eye, is acquired by the measuring unit. Processing a shape calculation means obtained based on optical information and a processing lens made of the temporary lens or another lens formed of the same material as the temporary lens based on the lens shape correction information obtained by the shape calculation means. And a lens processing means for forming an ophthalmic lens having a shape suitable for the patient's eye. 11. The lens processing means comprises laser processing means for irradiating a laser beam with the processing lens worn on the patient's eye to process the outer surface of the processing lens. 10. The manufacturing apparatus for an ophthalmic lens according to 10. 12. The measuring means is capable of measuring the optical characteristics of the patient's eye wearing the processing lens in parallel with the processing of the processing lens by the lens processing means. Item 11. The manufacturing apparatus for an ophthalmic lens according to Item 11. 13. The optical characteristic of the patient's eye is measured by the measuring means at appropriate time intervals in parallel with the processing of the processing lens by the lens processing means, and the processing measured by the measuring means. Based on the optical information of the patient's eye on which the working lens is worn, the shape calculation unit determines the processing amount for the outer surface of the processing lens required to realize the optical characteristics required for the patient's eye. 2. The amount of processing of the lens for processing by the lens processing means is sequentially changed and set according to the obtained processing amount.
2. The apparatus for manufacturing an ophthalmic lens according to 2. 14. An optical characteristic of the patient's eye is measured by measuring an optical characteristic of the patient's eye in a state where a temporary lens is attached to the patient's eye, and based on the optical information,
Compensating for aberrations in the patient's eye while wearing the temporary lens, and determining the shape of the temporary lens required to realize the optical characteristics required for the patient's eye. Design method of eye lens.