JP3829435B2 - Manufacturing method of spectacle lens - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for manufacturing a spectacle lens.
[0002]
[Prior art]
Eyeglass lenses are broadly classified into single focus lenses and multifocal lenses. A general manufacturing range and inventory form of each lens and a conventional manufacturing method will be described. In the following description, a plastic spectacle lens will be described.
[0003]
First, the single focus lens will be described. A single focus lens is used to correct the visual acuity of a myopic or hyperopic patient. FIG. 6 shows an example of the manufacturing range. The spherical power (hereinafter referred to as S power) ranges from about -15.00 [D] to +10.00 [D] in 0.25 [D] steps, and the astigmatic power (hereinafter referred to as C power) is 0. In the range of about .25 [D] to 6.00 [D], it is provided in steps of 0.25 [D] as with the S frequency. However, the range of the C frequency decreases in a stepwise manner when the S frequency exceeds -9.00 [D] in the example shown in FIG. However, the number of types of lenses is 2,225 only in the manufacturing range shown in FIG. 6. Depending on the refractive index and design of the lens, there is a lens having a wider manufacturing range.
[0004]
Next, in the form of inventory, the range between S frequency -10.00 [D] to +6.00 [D] and C frequency 0.25 [D] to 2.00 [D] is the part where there are many orders. Generally, they are stocked as molded lenses called finish lenses. A range other than the finish lens is infrequently ordered, so it is not stocked as a finish lens, and it is thicker than the finished dimensions, and it can be used to produce lenses with a frequency of several steps. Stocked as a lens (hereinafter referred to as semi-finished lens).
[0005]
Next, the manufacturing method of a single focus lens is demonstrated. Single focus lenses are molded by injecting lens material into a combination of a concave upper mold to define the object side surface of the lens and a convex lower mold to define the eyeball side surface. Manufactured by casting. In order for the finish lens to obtain a desired power, in the case of a spherical lens having only S power (hereinafter referred to as a spherical lens), a spherical surface or a rotationally symmetric aspheric surface is provided on the concave surface of the upper die, and a spherical surface is provided on the convex surface side of the lower die. Is provided. On the other hand, in the case of an astigmatic lens having C power in addition to S power (hereinafter referred to as an astigmatic lens), a spherical surface or a rotationally symmetric aspheric surface is provided on the concave surface side of the upper mold, and a toric surface is provided on the convex surface side of the lower mold. Manufactured by casting. Since the lens released after molding has an optical surface with sufficiently satisfactory accuracy, it becomes a completed lens through a dyeing process, a hard coat process, a vapor deposition process, and the like.
[0006]
On the other hand, there is a manufacturing method for processing a semi-finished lens into a finished lens. As in the case of the spherical lens of the finish lens, the semi-finished lens is manufactured by combining the upper mold and the lower mold and cast molding so that the wall thickness is thicker than the finished dimension. The above-mentioned lenses with a low order frequency and lenses with special prescriptions that specify the prism amount and lens thickness are treated as special order lenses, and it is necessary to manufacture lenses with different dimensions according to the prescription. Depending on the prescription, this specially ordered lens has a semispherical lens concave surface on the spherical surface if it is a desired spherical surface, and an astigmatic lens on the concave surface of the semifinished lens that has a generally desired toric surface shape. After roughing like this, sanding and polishing processes similar to lapping are performed to finish the optical surface of the lens precisely. In this sanding process and polishing process, the lens held in a dedicated jig is placed on a processing plate with a predetermined shape or curvature, and the lens and processing plate are slid relative to each other while water is poured onto the lens processing surface. The lens surface is processed by moving it. In the sanding process, the unevenness of the lens surface is reduced, and in the polishing process, it is finished to the accuracy that a desired appearance can be obtained. A series of processing methods such as rough cutting, sanding, and polishing are collectively referred to as polishing.
[0007]
The special prescription lenses that specify the prism amount and the lens thickness described above cannot be manufactured by the manufacturing method of the finish lens. Therefore, it is necessary to manufacture from the semi-finished lens even in the manufacturing range of the finish lens. Therefore, taking the production range shown in FIG. 6 as an example, it is necessary to prepare in advance the processing dish used for sanding and polishing processing having the same shape or curvature for 2225 types as the lens. is there.
[0008]
The lens thus obtained is usually called a polished lens. Since this polished lens has an optical surface with sufficiently satisfactory accuracy, it becomes a completed lens through a dyeing process, a hard coat process, a vapor deposition process, and the like in the same manner as the finish lens.
[0009]
Next, a manufacturing apparatus for obtaining the polishing lens will be described. First of all, the roughing machine uses a so-called curve generator that can cut a surface with a certain curvature, and a generator that can be developed to process a pseudo toric surface. It is ground or cut into a spherical surface or a toric surface close to a desired shape with a thickness considering the margin. The apparatus for performing sanding and polishing is basically the same mechanism, both of which have a mechanism for relatively sliding the processing plate and the lens, a means for generating pressure between the processing plate and the lens, and a lapping material. And means for supplying. As for this mechanism, for example, a lens that performs a triangular motion of the lens called the Udagawa method and rotation of the processing plate, and a device that performs a circular motion of the lens and rotation of the processing plate called the AO method are known. In addition, in processing, it is necessary to select a processing dish according to prescription. Also, the pads are exchanged according to the lens material and process. Incidentally, a glass spectacle lens is generally manufactured by roughing, sanding, and polishing as in the case of the plastic spectacle lens.
[0010]
Next, the multifocal lens will be described. Multifocal lenses can be divided into progressive multifocal lenses and multifocal lenses. These multifocal lenses realize the function of a single-focus lens for distance vision and the function of a single-focus lens for near vision with a single lens.
[0011]
Therefore, it is possible to correct the visual acuity for distance vision and near vision without changing glasses, and there is no trouble associated with the change.
[0012]
Progressive multifocal lenses have a progressive surface whose focal length continuously changes on the outer surface side of the lens, that is, on the convex surface side. Multifocal lenses are bifocal (bifocal) and trifocal (trifocal). Such a type is commercialized and has a curved surface for obtaining two or three focal lengths on the outer surface side of the lens, that is, on the convex surface side. Therefore, unlike a single focus lens, a multifocal lens has a power for distance vision and a power for near vision, and the absolute value of the difference between these two powers is referred to as addition power.
[0013]
In the following, description will be given taking an example of a progressive multifocal lens that is currently mainstream among multifocal lenses. The production range of the progressive multifocal lens is normally the same as the production range shown in FIG. In addition to this, in the case of a progressive multifocal lens, it is common that the aforementioned addition is provided in 13 steps from 0.50 [D] to 3.50 [D] in 0.25 [D] steps. Recently, it has become common to design the right-eye lens and the left-eye lens separately. In the case of a progressive multifocal lens, even in the same manufacturing range as a single focus lens, in addition to this addition and left and right design, the astigmatism prescription lens is a lens with the prescription astigmatism axis as the reference meridian of the progressive surface. Since it is necessary to set 180 types in 1 [°] steps every time, the number of types of lenses in the production range includes a huge number of 9942946 types including the astigmatic axis. Prescription lenses are not included.
[0014]
Next, a progressive multifocal lens manufacturing method. Since progressive multifocal lenses are basically all special order lenses, a polishing lens of the single focus lens is prepared according to prescription from a semi-finished lens having a progressive surface on the convex surface side. It is manufactured with almost the same method and apparatus as in the above case. That is, the semi-finished lens is cast-molded so that the object-side surface (convex surface) of the spectacle lens is a progressive surface with a predetermined performance, and the eyeball-side surface (concave surface) is thicker than the finished dimension. The concave side of the manufactured semi-finished lens is polished to a desired spherical surface if it is a spherical lens, or a desired toric surface shape if an astigmatic lens, depending on the prescription.
Process. In this way, in the case of astigmatism prescription with a progressive multifocal lens, the astigmatism axis with the main meridian of the convex progressive surface as the reference position must be set on the concave side, and this point is the polishing of the single focus lens in manufacturing. Different from the lens case. In the manufacturing range shown in FIG. 6, since the number of types of spherical and toric surfaces created on the concave side is the number of types of processing plates, the processing plate has the same 2225 types as in the case of a single focus lens. It becomes.
[0015]
In this way, the semi-finished lens for progressive multifocal lenses combines an upper mold having a progressive surface on the concave surface side and a lower mold having a spherical surface on the convex surface side so that the wall thickness is thicker than the finished dimensions. Manufactured by molding. In addition, lenses with S power and addition that are frequently ordered in the manufacturing range are combined with an upper mold having a progressive surface on the concave surface side and a lower mold having a spherical surface on the convex surface side, and finished by casting. May be manufactured. However, in general, the progressive multifocal lens has a very small amount of finish lens, and more than 95% is stocked as a semi-finished lens.
[0016]
Incidentally, Japanese Patent Laid-Open No. 5-19212 proposes a manufacturing method for increasing the manufacturing ratio of a finish lens to the limit even with a progressive multifocal lens of a special order lens. In this manufacturing method, most custom-made lenses are manufactured by casting, and the manufacturing ratio of the finish lens exceeds 90% despite the progressive multifocal lens. The manufacturing method is to prepare molds corresponding to the production range in advance, select the upper mold and lower mold to obtain the desired frequency according to the customer's prescription, combine this, and cast molding It is to obtain a lens that satisfies the prescription.
[0017]
Specifically, if the addition is 13 steps in the production range shown in FIG. 6, the type of upper mold having a progressive surface on the concave side is divided into five base curve sections, In this case, the total number is 130 types. In addition, 100 types of lower molds having a spherical surface on the convex surface side, which are used for manufacturing spherical type progressive multifocal lenses in combination with the above 130 types of upper molds, also manufacture astigmatic progressive multifocal lenses. Therefore, 2100 types of lower molds having a toric surface on the convex surface side are prepared, and a total of 2430 types of molds are arranged to produce a finish lens. In the case of an astigmatic progressive multifocal lens, cast molding is performed after the lower astigmatism axis is set with the main meridian of the upper progressive surface as a reference position according to prescription. The special prescription lens and the lens whose power exceeds the production range are manufactured by polishing from a semi-finished lens as described above.
[0018]
[Problems to be solved by the invention]
However, in the method for manufacturing a spectacle lens by polishing shown in the background art, first, since it is a rubbing process using a processing dish, it is necessary to prepare the processing dish for each refractive index and each frequency. . The processing dish is made by cutting or grinding aluminum, reinforced plastic, foamed urethane, or the like into a desired shape with a dedicated device. Depending on the frequency range, the processing dishes need to be arranged in finer steps every 0.25 [D]. In the case of the production range shown in FIG. 6, the number of types is equivalent to the number of types of lenses, ie 2225 or more. The refractive index of lens materials currently used as plastic lenses for spectacles is generally 1.50, 1.56, 1.60, 1.67, and the refractive index of the lens even if the shape of the processing dish is the same power. Therefore, the required number is 8900 or more.
[0019]
In terms of cost, the management man-hours of these processing dishes as the running cost, the storage space, and the manufacturing cost of the processing dishes as the initial cost are required. Other than the cost, the roughing process only cuts to the desired shape, regardless of whether it is plastic or glass, in order to ensure the production delivery date of the processing dish, the principle of processing, and to ensure productivity. The shape accuracy is determined by a sanding process and a polishing process for transferring the shape of the processing dish. Therefore, in order to guarantee the shape accuracy, it is necessary to strictly manage the processing error at the time of manufacturing the processing dish that is the basis, and there are many problems.
[0020]
Further, in Japanese Patent Application No. 7-306189, a curved surface obtained by combining a progressive surface created on the convex side of the lens with a spherical surface or a toric surface created on the concave side according to the prescription is provided. A spectacle lens has been proposed that is created on one surface of the concave surface to dramatically improve optical characteristics. Hereinafter, a lens having such a curved surface on the lens concave surface side is referred to as an inner surface progressive multifocal lens. This inner surface progressive multifocal lens can also be manufactured by a lens manufacturing method based on cast molding disclosed in the above-mentioned JP-A-5-19212.
[0021]
Here, consider a case where an inner surface progressive multifocal lens of a type having a spherical surface on the convex side of the lens is manufactured in the manufacturing range shown in FIG. First, the type of the upper mold having a spherical surface on the concave surface side is set to 10 types of 10 base curve sections. Next, the lower mold is combined with the upper mold, but there are 2626 lower molds with a progressive surface on the convex side for spherical prescription lenses in 0.25 [D] steps, and further for each astigmatic axis for astigmatic prescription lenses. It is necessary to have a total of 9940320 types of lower molds having a curved surface on the convex surface side, which is a combination of a surface and a toric surface according to prescription, in 0.25 [D] steps in both S frequency and C frequency. Even if the number of lower molds held per type is 10, the mold cost alone can be as high as several hundred billion yen. In addition, the inventory management of these types of molds is unrealistic because the management itself is unrealistic. Furthermore, as mentioned earlier, the lens manufacturing method by cast molding specifies the prism amount and lens thickness. However, some special prescription lenses cannot be manufactured.
[0022]
Conventionally, the curve generator used for creating the surface of the eyeball side, etc. can only process either a spherical surface or a toric surface due to its structure and the principle of processing by sliding with a processing dish, It is completely impossible to create a curved surface combining the progressive surface and the spherical surface or toric surface shown in.
[0023]
Therefore, in the present invention, as described above, there is provided a spectacle lens manufacturing method and a manufacturing apparatus capable of supplying an internal progressive multifocal lens that cannot be practically supplied by a conventional manufacturing method. It is aimed. Furthermore, not only a progressive multifocal lens but also a manufacturing method and a manufacturing apparatus capable of manufacturing a wide variety of spectacle lenses at a low cost in a short period of time, instead of a conventional manufacturing method using polishing using a processing dish. The object is to provide a manufacturing method and a manufacturing apparatus in which the processing plate itself can be omitted, and the manufacturing cost, management man-hours, storage space, etc. of the processing plate can be omitted. It is another object of the present invention to eliminate the need for a production period of a processing dish that has conventionally required several months, and to greatly reduce the cost and shorten the delivery time.
[0024]
[Means for Solving the Problems]
For this reason, in the present invention, the surface creation of the spectacle lens is performed based on data for numerical control processing (hereinafter also referred to as “NC processing data”). In other words, the spectacle lens manufacturing method of the present invention is based on numerical control processing data processed by taking into account the conditions of the spectacle lens wearer in the machining of the semi-finished lens for forming the spectacle lens. A method of manufacturing an eyeglass lens, comprising: an NC shape creation step to be performed; and a profile polishing step in which the semi-finished lens surface that has been machined in the NC shape creation step is polished by profile polishing, Before performing the creation process, after selecting a semi-finished lens suitable for machining based on the numerical control machining data, measure the shape of the surface to be processed of the semi-finished lens, and the measurement result A correction step of calculating a reference curve for obtaining a desired lens power from the above and correcting the numerical control processing data based on the calculation result It is characterized by having. Further, in the method for manufacturing a spectacle lens according to the present invention, in the NC shape creation step, the step amount near the inflection point generated when machining is performed is 0.0005 mm or more excluding the surface roughness component. The semi-finished lens is machined so that the maximum surface roughness Rmax of the machined surface is 0.001 mm or more and 0.010 mm or less. It is characterized as
[0025]
The spectacle lens manufacturing method and manufacturing apparatus according to the present invention is characterized in that NC processing that is not employed in the conventional spectacle lens manufacturing is employed in the shape creation processing of the spectacle lens surface itself. By using the method or the manufacturing apparatus, any spectacle lens having any curved surface can be manufactured by changing the NC processing data using a common manufacturing apparatus or a few types of manufacturing apparatuses. Therefore, in the present invention, the eyeball side surface of the inner surface progressive multifocal lens in which the progressive surface and the toric surface are synthesized, which is different for each spectacle lens wearer (user, customer), is processed by changing the NC processing data. By using the manufacturing method and manufacturing apparatus of the present invention, it is possible to supply the inner surface progressive multifocal lens in earnest. Further, in the present invention, a wide variety of spectacle lenses can be manufactured simply by changing the NC processing data, so that it is not necessary to manufacture a wide variety of processing dishes in advance and manage them. Therefore, various types of spectacle lenses can be supplied at a low price, and the delivery time can be greatly shortened.
[0026]
It is also possible to perform from the creation of the surface shape of the spectacle lens to the finishing using NC processing with a single processing method or processing apparatus. However, in a spectacle lens that requires high surface accuracy, the processing time can be significantly shortened by changing the processing method or processing device in the middle of the process from creation of the surface shape to finishing of the lens surface. For example, after the surface shape is created by NC processing, the manufacturing time can be greatly shortened by finishing the lens surface by copying and polishing. In addition, after the surface shape is created by the NC processing step, the manufacturing time can also be shortened by performing the NC polishing step of performing polishing processing based on numerical control processing data that defines the surface shape to be polished. Furthermore, in terms of shortening the manufacturing time, it is effective to cut out the semi-finished lens in the NC shape creation process.
[0027]
Thus, in the spectacle lens manufacturing method and manufacturing apparatus according to the present invention, spectacle lenses having any surface can be manufactured by changing the NC processing data. Therefore, the spectacle lens can be worn before the NC shape creation process. By creating NC processing data for each spectacle lens to be processed in consideration of the conditions of the operator, customized spectacle lenses suitable for individual users can be manufactured and provided in earnest.
[0028]
Select a semi-finished lens suitable for machining based on NC machining data, measure the shape of the surface of the semi-finished lens to be machined, and correct the NC machining data. Thus, it is possible to create NC processing data suitable for actual cutting processing taking into account errors of the semi-finished lens and the like, and processing can be performed based on the data.
[0029]
In the NC shape creation step of the eyeglass lens manufacturing method of the present invention, the machining is performed so that the maximum surface roughness Rmax of the machined surface is 0.010 mm or less. it can. If this condition is used, even if the polishing step is performed without performing the subsequent sanding step, the spectacle lens having a desired optical surface is obtained without unnecessarily increasing the time required for the polishing step. Can be manufactured in a short time. In addition, if the maximum surface roughness Rmax of the surface machined in the NC shape creation process is made as small as the optical surface, the polishing process itself becomes unnecessary by performing hard coating as it is or after that. You can also.
[0030]
In addition, the method for manufacturing a spectacle lens according to the present invention includes a process for machining the surface after machining so that the maximum surface roughness Rmax of the work surface is 0.001 mm or more and 0.010 mm or less in the NC shape creation process. This polishing can be performed by copying polishing. By using this condition, it is possible to manufacture a spectacle lens with the desired optical surface and good appearance accuracy in a short time without unnecessarily increasing the time required for the NC shape creation process. It becomes. Here, the reason why the maximum surface roughness Rmax is set to 0.001 mm or more is that if it is less than 0.001 mm, the time required for the NC shape creation process becomes unnecessarily long. In this case, the thickness is preferably 0.002 mm or more, and more preferably 0.003 mm or more.
[0031]
Further, in the NC shape creation process of the eyeglass lens manufacturing method of the present invention, the step amount in the vicinity of the inflection point generated on the surface to be machined when machining is performed, except for the surface roughness component. It is possible to perform machining so as to be 005 mm or less. If this condition is used, even if the polishing step is performed without performing the sanding step for removing the step, the time required for the polishing step is not increased, and the spectacle lens having the desired optical surface is obtained. It becomes possible to manufacture in a short time. Here, the reason why the step amount is set to 0.005 mm or less is that it is not preferable because the time required for the polishing step tends to be long when the sanding step is omitted after the range exceeding 0.005 mm. Even if the polishing process is performed for a long time, it is difficult to completely remove the step, and even if the step can be completely removed, the shape is created through a long polishing process. This is because the shape accuracy of the optical surface created in the process is deteriorated or polishing sagging occurs. In addition, since the sanding step can be omitted, there is an effect that the polishing dish required in the sanding step can be eliminated.
[0032]
Further, in the method for manufacturing a spectacle lens according to the present invention, the step amount in the vicinity of the inflection point generated at the time of machining is 0.0005 mm or more and 0.005 mm or less excluding the surface roughness component. In this way, the surface can be polished by copying and polishing. If this condition is used, it is not necessary to use an expensive NC shape generating device with extremely small steps, and the manufacturing cost can be reduced. In addition, since it is not necessary to slow down the processing speed to suppress the occurrence of steps, the shape accuracy and appearance accuracy with the desired optical surface are eliminated without unnecessarily increasing the time required for the NC shape creation process. It is possible to manufacture a good spectacle lens in a short time.
[0033]
DETAILED DESCRIPTION OF THE INVENTION
Taking a plastic spectacle lens as an example, a method and apparatus for manufacturing a spectacle lens according to the present invention will be described. As shown in FIG. 1 using a block diagram, prescription data 100 obtained from a customer is transmitted to a host computer 101 in the manufacturing department of the lens manufacturer. This prescription data generally includes S power, C power, astigmatism axis, addition power, prism, lens thickness, lens diameter, color and the like in the case of a progressive multifocal lens. In addition, in the case of a single focus lens, prescription data such as S power, C power, astigmatism axis, prism, lens thickness, lens diameter, color, and the like are included, and these prescription data 100 are obtained from a terminal equipped in a spectacle retailer. It is transmitted directly to the host computer 101 of the manufacturing department of the lens manufacturer by online. Alternatively, a relay base receives a prescription data 100 from a retail store by a transmission means such as a telephone and a facsimile, and is transmitted online from the relay base. Then, based on the prescription data 100 transmitted to these host computers 101, in the calculation step 102, the prescription data is processed into production data for the production line by the calculation computer. Based on this production data, that is, the customer The combination of curved surfaces based on the prescription is calculated, and the lens shape is designed for each customer prescription. This calculation process 102 has a function as a machining data generation process for NC machining, and the numerical control cutting machine shown in FIG. 2 or the numerical control turning shown in FIG. 3 used in the shape creation process 106 described below. NC processing data (first NC processing data) for creating a lens design shape with a machine, and NC processing for polishing a curved surface created in the shape creation process with the numerically controlled polishing machine shown in FIG. The data (second NC processing data) and the polishing conditions of the profile polishing machine shown in FIG. 4 are also calculated at the same time, and these are stocked in a storage device provided in the computer for calculation.
[0034]
Subsequently, in a lens selection step 103 for selecting a semi-finished lens, a semi-finished lens that is a source for processing a lens that satisfies the customer's prescription is selected. In the step 103 of selecting the semi-finished lens, the corresponding semi-finished lens is picked manually or automatically using an automatic warehouse or the like.
[0035]
As described in the prior art, semi-finished lenses are manufactured by casting using a mold, but even if molded with the same mold, the shape of each semi-finished lens varies depending on the polymerization conditions, annealing conditions, etc. In some cases, the shape of the mold cannot be transferred sufficiently. In such cases, the desired shape accuracy of the semi-finished lens is often not obtained. Therefore, a semi-finished lens measurement necessity determination step 104 is provided, and in the measurement and calculation step 105, the shape of the selected semi-finished lens is measured in advance, and a reference curve for obtaining a desired lens power from the measurement result. Is calculated by a computer and fed back to the calculation of the curved surface to be created. By providing the step 105 for performing such correction, the shape error of the semi-finished lens is canceled, and as a result, a curved surface to be created to obtain a desired lens power can be obtained. At this time, the surface for measuring the shape may be only the surface on the opposite side to the surface for which the shape is to be created among the uneven surfaces of the selected semi-finished lens. As a shape measurement method, if the measurement surface is a semi-finished lens having a spherical shape, the radius of curvature can be easily measured with a cross-sectional shape measuring instrument such as a product name: Form Talysurf manufactured by Rank Taylor Hobson. . Further, when the surface to be measured has a free-form surface such as a progressive surface, it is possible to perform shape measurement using a shape measuring device using an interferometer, a three-dimensional measuring device, or the like.
[0036]
When the shape accuracy of the semi-finished lens is stable, it is determined in the necessity determination step 104, and the measurement step (correction step) 105 can be omitted. This stable shape accuracy is, for example, when the measurement surface is a spherical surface, and the curvature radius of the spherical surface of the semi-finished lens in the same production lot, that is, the standard deviation of the curve is less than one quarter of the lens power tolerance, In addition, the difference between the average value of the curve and the nominal curve is set to 1/5 or less of the frequency tolerance. In addition, when the measurement surface is a free-form surface, a guideline can be set by applying this idea.
[0037]
Next, a surface shape is generated in accordance with the NC processing data generated based on the prescription data of each user in the shape creation step (NC processing step) 106, and further polishing is required in step 107 for determining whether polishing is necessary. In this case, the polishing step 108 is performed, and finally the inspection is performed in the inspection step 109, and the eyeglass lens is manufactured through these steps.
[0038]
Hereinafter, the shape creation step 106 and subsequent steps will be described in more detail. First, in the shape creation step 106, the semi-finished lens selected in the semi-finished lens selection step 103 is set on the chuck 202 of the numerically controlled cutting machine 200 of the spectacle lens manufacturing apparatus 150 shown in FIG. The shape creation is performed by transmitting NC processing data (first NC processing data) stocked in the apparatus to the numerically controlled cutting machine 200. Normally, NC machining data has a huge amount of data, so it is temporarily stored in a storage device in a numerically controlled cutting machine, or NC machining data is sent directly to a numerically controlled cutting machine to move the machine and create a shape. In addition to the numerically controlled cutting machine, the same shape can be created by using a numerically controlled grinding machine or a numerically controlled turning machine as the means for generating the shape.
[0039]
The cutting tools used in these shape creation means are diamond cutters or carbide cutters if cutting, metal bonds or electrodeposition diamond wheels if grinding, and diamond or carbide if turning. And so on. In the shape creation process using these shape creation means, rough machining and finishing are performed with a single chuck, and in finishing machining, the surface roughness of the workpiece after machining is set to a maximum surface roughness Rmax (hereinafter referred to as Rmax) of 0. Finish to 01 to 10 [μm] or less. Further, as shown in FIG. 1, a desired optical surface can be obtained by providing a polishing step 108 in the next step as required. Depending on the material of the plastic lens, if this surface roughness is set to 0.05 [μm] or less at Rmax, in the case of a plastic spectacle lens, the hard coat process following the shape creation process 106 even if the polishing process 108 is omitted. A desired optical surface can be obtained by performing a surface treatment (not shown). Even if the surface roughness is the same, whether or not a desired optical surface can be obtained by performing the surface treatment in the hard coat process largely depends on the plastic lens material.
[0040]
On the other hand, if a desired optical surface cannot be obtained simply by performing a surface treatment in the hard coat process, a polishing step 108 is provided after shape creation, and the lens surface after shape creation is polished to a smooth optical surface. Finish. Specifically, the second NC processing step is performed by the profile polishing machine 400 shown in FIG. 4 or the numerically controlled polishing machine 500 shown in FIG. 5, and the desired optical shape is not destroyed without breaking the curved surface shape created in the shape creation step 106. Polish the surface. These polishing means are equipped with an elastic polisher head, but a non-woven fabric having a length of about 0.1 to 5 [mm] made of rayon, nylon or the like is disposed on the surface of the polisher head. Furthermore, polishing with Al2 O3 as the main component of the abrasive, and mixed with oxide, water, etc.
It is also possible to improve the polishing efficiency by pouring water between the workpiece to be polished and the nonwoven fabric.
[0041]
Example 1
In the following, each process and each device will be described by taking as an example the case of manufacturing an inner surface progressive multifocal lens proposed in Japanese Patent Application No. 7-306189 having a curved surface combining a progressive surface and a toric surface on the concave surface side of the lens. Will be described in more detail. In the prescription data 100 of this example, the lens diameter is 80 [mm], the spherical power (S power) +2.00 [D], the astigmatic power (C power) -1.75 [D], the astigmatic axis 55 degrees, the addition power. The personal information of the user (customer) of 2.25 [D] and prism 1.20 down is included. First, in order to satisfy the prescription, a progressive surface with a base curve of 4.00 [D] and an addition power of 2.25 [D] created on the concave side of the lens, and an astigmatic power of -1.75 [D] A curved surface in which a toric surface having a base curve axis in the direction of 35 degrees counterclockwise with respect to the main meridian of the progressive surface as viewed from the lens concave surface side was synthesized by a computer for calculation. At this time, the final center thickness of the lens was also calculated, and the result was 3.35 [mm]. Subsequent to these calculations, NC machining data for machining the curved surface calculated above with the numerically controlled cutting machine 200 shown in FIG. 2 is created in the calculation computer 102 in the calculation step 102 and installed in the calculation computer. Recorded on the hard disk.
[0042]
Next, a semi-finished lens for obtaining an internally progressive multifocal lens that satisfies the prescription is selected in the selection step 103. In this example, the semifinished lens has a spherical surface on the convex surface side, and its radius of curvature is 110.333 [mm]. A semi-finished lens having a nominal base curve of 6.00 [D] was selected. The refractive index of the lens material of the semi-finished lens is 1.661. Further, the variation of the base curve in the same production lot including the selected semi-finished lens was as small as 0.005 [D] as a standard deviation, and the shape accuracy was extremely stable. Further, the average value of the base curve is 5.998 [D], and the difference from the nominal base curve is extremely small. For this reason, it is determined in the shape necessity determination step 104 that the shape measurement step 105 is unnecessary, and no correction of the lens design shape calculated by the computer for calculation is instructed. The production lot of the semi-finished lens is 30 sheets / lot.
[0043]
Subsequently, in the shape creation step 106, the semi-finished lens is gripped by the work chuck 202 of the numerically controlled cutting machine 200, and the NC processing data is numerically received from the host computer 101 using the DNC operation mode of the numerically controlled cutting machine 200. The lens design shape is created by cutting while transmitting directly to the control cutting machine 200. As shown in time 2, the configuration of the numerically controlled cutting machine 200 of this example is such that X-axis positioning means 205 that performs linear positioning in a substantially horizontal direction, and linear positioning in a horizontal direction that is substantially orthogonal to the X-axis positioning means 205. Y-axis positioning means 208 for performing, Z-axis positioning means 212 for performing linear positioning in a substantially vertical direction, cutting tool rotating means 213 mounted on the Z-axis positioning means 212, and workpiece axis rotating means 216 capable of indexing the angle. The The Z-axis positioning means 212 is provided mainly for the purpose of aligning the core height of the workpiece 201 and the circular cutter 215. The center coordinates of the circular cutter 215 are positioned in the normal direction set at the workpiece machining point using the three axes of the X-axis positioning unit 205, the Y-axis positioning unit 208, and the workpiece axis rotating unit 216. By continuously positioning the center coordinates of the circular cutter 215 corresponding to this processing point, the shape creation based on the lens design shape is performed.
[0044]
The minimum positioning accuracy of the numerically controlled cutting machine 200 used in this example is 0.1 [μm] for the linear positioning means and 0.001 [°] for the workpiece axis rotating means. Further, the feed pitch in the workpiece radial direction is 0.5 [mm / rotation], the angular division pitch in the workpiece circumferential direction is divided into 360 for one round, the finishing cut amount is 3.0 [mm], and the cutting tool has a diameter of 70.2. [Mm], a two-blade cemented carbide cutter, 15000 [r. p. m] and used. The shape of the curved surface machined under these conditions had sufficient shape accuracy to satisfy the prescription.
[0045]
When the numerically controlled cutting machine 200 is used for the shape creation process 106, the surface roughness of the obtained spectacle lens is 4.5 [μm] at Rmax, and the optical surface required for the lens cannot be obtained by cutting alone. Subsequently, a polishing process 105 is performed. In this example, the curved surface created in the shape creation process is polished using the copying polishing machine 400 shown in FIG. 4 in the spectacle lens manufacturing apparatus 150. The apparatus configuration of the copying polishing machine 400 includes a work rotation shaft 403, a polisher rotation shaft 407, a swing shaft that swings in a direction indicated by an arrow 408 (not shown), and a water injection means 409 for injecting polishing liquid or the like. In addition, it is possible to generate a pressure necessary for polishing between the workpiece 401 and the polisher head 410 by a load applying means (not shown). The polisher head 410 is composed of a sheet 404 having flexibility such as rubber and a polisher head casing 405. In a sealed space between the sheet 404 and the polisher head casing 405, compressed air indicated by 406 is provided. It is possible to follow an arbitrary workpiece shape by press-fitting a gas such as water or a liquid such as water and inflating the sheet 404 with the pressure. With the swollen sheet 404 following the shape of the workpiece 401, the workpiece rotating shaft 403 and the polisher rotating shaft 407 are rotated and a swinging operation is applied by the swinging shaft. It becomes possible to polish to a desired optical surface without breaking the workpiece shape created in the shape creation step. Further, a polishing cloth (not shown) may be attached to the surface of the sheet 404 in accordance with the material of the workpiece to be polished to further improve the polishing performance.
[0046]
In this example under this configuration, although not shown, a nonwoven fabric having a length of 0.8 [mm] using rayon as a raw material is attached to the surface of the sheet 404 with an adhesive, and the sheet 404 and the polisher head are attached. About 3.2 [kgf / cm in a sealed space between the housing 405 ² The compressed air 406 is fed to expand the sheet 404 so that the sheet 404 substantially follows the curved surface created in the shape creation process. Further, using a load applying means (not shown), the work head 401 and the polisher head 410 are approximately 32.5 [kgf / cm] between them. ² ] Pressure was generated. In this state, the polisher head shaft 407 is moved about 100 [r. p. m], the work shaft 403 is moved about 5 [r. p. m], and a reciprocating motion of 6 reciprocations per minute was applied by a rocking means (not shown). During the series of operations, the polishing liquid 411 (trade name: Polyplastic 103A manufactured by Fujimi Incorporated) was poured from the water pouring means 409 between the workpiece 401 and the polisher head 410. As a result, the necessary optical surface could be obtained in about 10 [minutes]. Further, since the polishing was performed without substantially losing the shape at the time of forming the shape, the measurement values at the time of dimensional inspection were the lens diameter 80.09 [mm], the S power +2.02 [D], and the C power −1. .77 [D], astigmatic axis 55 [°], addition 2.25 [D], prism 1.17 down, finished center thickness 3.31 [mm], and all measured values satisfy the standard values. Thus, an inner surface progressive multifocal lens that sufficiently satisfies the prescription could be obtained.
[0047]
The numerically controlled cutting machine shown in FIG. 2 can be used as a numerically controlled grinding machine by changing the cutting tool to be used from a circular cutter 215 to a grinding wheel such as a metal bond, and has the same shape as the numerically controlled cutting machine. Accuracy and surface roughness can be obtained.
[0048]
Moreover, even if the numerically controlled cutting machine 200 is replaced with the numerically controlled turning machine 300 shown in FIG. 3, substantially the same result can be obtained. A numerically controlled turning machine 300 includes an X-axis positioning unit 305 that performs linear positioning in a substantially horizontal direction, a Y-axis positioning unit 308 that performs linear positioning in a horizontal direction substantially orthogonal to the X-axis positioning unit 305, and a workpiece axis capable of indexing an angle. A rotating means 306 and a tool post 311 are included. In the same way as the numerically controlled cutting machine, the numerically controlled turning machine uses the three axes of the X-axis positioning unit 305, the Y-axis positioning unit 308, and the workpiece axis rotation unit 306 in the normal direction set at the machining point of the workpiece 301. The center coordinate of the tip R of 307 is positioned. By continuously positioning the center coordinates of the tip R of the cutting tool 307 corresponding to this processing point, a shape is created based on the lens design shape. At this time, the workpiece 301 is 100 to 2000 [r. p. m] is rotated by the work shaft rotating means 306.
[0049]
In this example, the copying polishing machine 400 is used in the polishing step 108. However, the numerically controlled polishing machine 500 shown in FIG. 5 is used, and the NC processing data for polishing (second NC processing data) is used. It goes without saying that almost the same result is obtained even if polishing is performed. As shown in FIG. 5, the numerically controlled polishing machine 500 includes an X-axis positioning unit 505 that performs linear positioning in a substantially horizontal direction, and a Y-axis positioning unit 507 that performs linear positioning in a horizontal direction substantially orthogonal to the X-axis positioning unit 505. Design of the four axes of the rotary table 503 having the angle indexing function and the R axis positioning means 504 having the angle indexing function, or the three axes of the X axis positioning means 505, the rotary table 503, and the R axis positioning means 504 and the lens. Based on the NC machining data calculated in advance from the shape, the polisher head 510 and the workpiece 501 are relatively positioned, and the central axis of the polisher head 510 or the polisher head 510 in the normal direction at the machining point of the workpiece 501 is determined. Arbitrary parts of the surface are made to coincide with each other with the load adding means 513 from that direction. To polishing pressed against the Rishaheddo 510. As a result, it is possible to polish to a desired optical surface without breaking the curved surface shape created in the shape creation step 106.
[0050]
(Example 2)
Next, an example in which a progressive multifocal lens having a progressive surface on the convex surface side of the lens is manufactured by the manufacturing method of the present invention will be described with reference to the drawings.
[0051]
In the prescription data 100 of this example, the lens diameter is 80 [mm], the spherical power (S power) -3.25 [D], the astigmatic power (C power) -0.75 [D], the astigmatic axis 90 degrees, the addition Data of degree 1.00 [D] and down prism 0.75 are included. In order to satisfy this prescription, the toric surface of the base curve 5.75 [D] and the cross curve 6.50 [D] created on the concave surface side of the semifinished lens selected in the semifinished lens selecting step 103 is calculated. The calculation was performed at 102 using a computer for calculation. At this time, the final center thickness of the lens was also calculated and found to be 1.55 [mm]. Subsequently, NC processing data for processing the calculated toric surface with a numerically controlled lathe 300 shown in FIG. 3 was created by a calculation computer and recorded on a hard disk equipped in the calculation computer 101.
[0052]
Next, in the semi-finished lens selection step 103, a semi-finished lens for obtaining a progressive multifocal lens that satisfies the prescription is selected. In this example, the nominal curvature radius is 264.8 [mm] on the convex surface side. A semi-finished lens having a refractive index of 1.661 having a progressive surface with a 2.50 [D] base curve and an addition of 1.00 [D] was selected. The variation of the base curve within the same production lot including the selected semi-finished lens is as large as 0.072 [D] as a standard deviation, and the average value of the base curve is 2.551 [D]. Since it was unstable, it was determined that measurement was necessary in the measurement necessity determination step 104, and shape measurement was performed with a three-dimensional measuring device in the measurement step 105. As a result of the measurement, the base curve of the semi-finished lens used in this example was 2.542 [D]. Therefore, in order to create a toric surface corrected by 0.042 [D], which is the difference from 2.50 [D], which is the nominal base curve, the calculation computer recalculates the data for NC machining. Asked. At this time, the finished center thickness of the lens was recalculated simultaneously with the NC processing data, but the finished center thickness was the same value as before the recalculation. The production lot of the semi-finished lens has a configuration of 20 pieces / lot.
[0053]
Subsequently, the semi-finished lens is gripped by the work chuck 302 of the numerically controlled turning machine 300 shown in FIG. 3, and the NC machining data stored in the host computer 101 is stored using the DNC operation mode of the numerically controlled turning machine. The shape was created by turning while directly transmitting to the numerically controlled turning machine 300. The configuration of the numerically controlled turning machine 300 is as described in the first embodiment. The minimum positioning accuracy of the numerically controlled turning machine used in this example is 0.1 [μm] for the linear positioning means, and the workpiece axis The rotation means is 0.01 [°]. The tip R of the cutting tool 307 is 4.0 [mm], and the work rotation speed is 750 [r. p. m], the feed pitch in the workpiece radial direction was 0.01 [mm / rotation], the angular division pitch in the workpiece circumferential direction was divided into 360 rounds, and the finish cut depth was 2.0 [mm].
[0054]
The shape of the toric surface that was turned under these conditions had sufficient shape accuracy to satisfy the prescription. Further, the surface roughness Rmax was 0.014 [μm], and the necessary optical surface was obtained only by turning. Therefore, it was determined that the polishing was unnecessary in the polishing necessity determining step 107, and the polishing 108 was omitted. However, since the optical surface was not at a level where dimensional inspection could be performed with a lens meter, dimensional inspection was performed after hard coat processing. As a result, the measured values at the time of inspection were as follows: lens diameter 79.96 [mm], S power −3.26 [D], C power −0.77 [D], astigmatism axis 90 [°], addition power 0.98. The measured values of [D], down prism 0.75, and finished center thickness 1.53 [mm] all satisfy the standard values, and a progressive multifocal lens sufficiently satisfying the prescription can be obtained.
[0055]
In this embodiment, the numerically controlled turning machine 300 is used as a means for creating a shape. However, even if the shape is created using the numerically controlled cutting machine 200 or the numerically controlled grinding machine as in the first embodiment, the shape creation is almost the same. It goes without saying that results are obtained. However, depending on the size of the surface roughness after the shape creation process, there is a case where the polishing process by the copying polishing machine 400 or the numerically controlled polishing machine 500 is required as in the first embodiment.
[0056]
Although it is rare, when using a production lot that contains a large amount of semi-finished lenses with a large variation in the base curve of the semi-finished lens or a large deviation from the nominal base curve as in this example, the block shown in FIG. If the lens manufacturing process is performed by changing the order of the calculation process 102 and the semi-finished lens selection process 103 in the figure, there is a case where there is no need for recalculation and the efficiency is improved.
[0057]
Example 3
Next, an example in which a progressive surface is created on the convex surface side of a semi-finished lens and a desired progressive multifocal lens is manufactured by the method for manufacturing a spectacle lens of the present invention will be described with reference to the drawings.
[0058]
The prescription data 100 of this example includes data of lens diameter 70 [mm], spherical power (S power) -10.50 [D], addition 1.50 [D], and prism 2.00 up. Yes. Therefore, in order to satisfy the prescription, in the calculation step 102, a progressive surface with a base curve of 1.00 [D] and an addition of 1.50 [D] created on the convex surface side of the semi-finished lens was calculated by a computer for calculation. . At this time, the finished thickness of the lens was also calculated and found to be 1.05 [mm].
[0059]
In this example, the circular cutter 215 of the numerically controlled cutting machine 200 shown in FIG. 2 was changed to a metal bond diamond wheel (not shown) and used as a numerically controlled grinding machine.
[0060]
Subsequently, in calculation step 102, NC processing data for processing the progressive surface calculated above with the numerically controlled grinding machine was created with a calculation computer and recorded on a hard disk equipped in the calculation computer. .
[0061]
Next, in the semi-finished lens selection step 103, a semi-finished lens for obtaining a progressive multifocal lens satisfying the above prescription is selected. In this example, the concave surface has a spherical surface, and its radius of curvature is 57.565 [mm. ], Semi-finished lenses having a nominal base curve of 11.50 [D] were selected. The refractive index of the lens material of the semi-finished lens is 1.661. Further, the variation of the base curve in the same production lot including the selected semi-finished lens was as small as 0.002 [D] as a standard deviation, and the shape accuracy was extremely stable. Further, since the average value of the base curve is 11.492 [D] and the difference between the nominal base curve value is extremely small, the above-described shape measurement is unnecessary as in the first embodiment. Therefore, it is not necessary to correct the lens design shape calculated above. The production lot of the semi-finished lens is 30 sheets / lot.
[0062]
Subsequently, in the shape creation step 106, the semi-finished lens is gripped by a work chuck (not shown) of a numerical control grinding machine, and the NC processing data is transferred to the numerical control grinding machine using the DNC operation mode of the numerical control grinding machine. While directly transmitting, the lens design shape was created on the convex surface side of the semi-finished lens by grinding. The configuration of the numerically controlled grinding machine is the same as that of the numerically controlled cutting machine except for the difference in cutting tools. The minimum positioning accuracy of the numerically controlled grinding machine used in this example is 0.1 [μm] for the linear positioning means and 0.001 [°] for the workpiece axis rotating means. Also, the feed pitch in the workpiece radial direction is 0.75 [mm / rotation], the angular division pitch in the workpiece circumferential direction is divided into 360 rounds, the finishing cut is 0.2 [mm], and the cutting tool has a diameter of 68. A metal bond diamond wheel of 2 [mm] and 500 mesh is 10000 [r. p. m] and used. The shape of the curved surface that was ground under these conditions had sufficient shape accuracy to satisfy the prescription. However, the surface roughness was Rmax 6.2 [μm], and the optical surface required for the lens could not be obtained only by grinding.
[0063]
This is followed by polishing
Processing 108 was performed. In this example, the curved surface created with the profile polishing machine shown in FIG. 4 was polished. The apparatus configuration of the profiling machine is as described in the first embodiment. In this example, although not shown, a non-woven fabric having a length of 0.8 [mm] using rayon as a raw material is attached to the surface of the sheet 404 with an adhesive, and the sheet 404 and the polisher head housing 405 About 2.4 [kgf / cm in the sealed space between ² The compressed air 406 is fed to expand the sheet 404 so that the sheet 404 substantially follows the curved surface whose shape has been created. Further, using a load applying means (not shown), about 26.9 [kgf / cm] between the workpiece 401 and the polisher head 410 is used. ² )] Pressure was generated. In this state, the polisher head shaft 407 is moved about 120 [r. p. m], the work shaft 403 is moved about 5 [r. p. m] and a reciprocating motion of 3 reciprocations per minute was applied by a rocking means (not shown). During the series of operations, the polishing liquid 411 (trade name: Polyplastic 103A manufactured by Fujimi Incorporated) was poured from the water pouring means 409 between the workpiece 401 and the polisher head 410. As a result, the required optical surface could be obtained in about 13 [minutes]. In addition, since the shape was created without substantially losing the shape at the time of creating the shape, the measured values at the dimensional inspection were 70.06 [mm] for the lens diameter, 10.46 [D] for the S power, and 1. 50 [D], prism 1.92 up, finished center thickness 1.11 [mm], and all measured values satisfied the standard value, and a progressive multifocal lens sufficiently satisfying the prescription could be obtained. .
[0064]
As described above, according to the spectacle lens manufacturing method and manufacturing apparatus of this example, a cutting means for calculating a combination of curved surfaces based on a customer's prescription, calculating processing data, and creating a desired curved surface, or Grinding means, turning means, in addition to these, means for calculating the reference data for measuring the shape of the semi-finished lens and obtaining the desired power, and polishing means, can create curved surfaces of any combination according to the prescription It is. As a result, not only the processing dish and a large amount of molds required in the prior art become unnecessary, but various types of spectacle lenses can be easily manufactured and supplied at low cost. The conventional casting multifocal lens is not limited to the conventional progressive multifocal lens, and the prior art cast molding method requires enormous cost and time, and cannot be practically manufactured by the manufacturing method by polishing. Japanese Patent Application No. 7-306189 In addition, the inner surface progressive multifocal spectacle lens described in 1) can be provided with a short delivery time and low cost.
[0065]
【The invention's effect】
Thus, in the present invention, the object side surface or eyeball side surface of the spectacle lens is different from a conventional casting method, a polishing apparatus using a curve generator and a processing dish, or a manufacturing method combining these, Manufactured by NC machining based on machining data. For this reason, spectacle lenses having any curved surface can be manufactured by changing the NC processing data using a common manufacturing apparatus or a few types of manufacturing apparatuses. Therefore, in the present invention, it is possible to supply in full scale an internally progressive multifocal lens that cannot be practically supplied by the conventional manufacturing method, and spectacles having different surfaces for each spectacle lens wearer. The lens can be provided with an appropriate delivery date and price. Also, by using the manufacturing method and manufacturing apparatus of the present invention, a wide variety of spectacle lenses can be manufactured simply by changing the NC processing data, so that it is not necessary to manufacture a wide variety of processing dishes in advance and manage them. . Therefore, not only the inner surface progressive multifocal lens but also various types of spectacle lenses can be supplied at a low price, and the delivery time can be greatly shortened.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a manufacturing process of a spectacle lens in the present invention.
FIG. 2 is a front view showing a numerically controlled cutting machine of the spectacle lens manufacturing apparatus of the present invention.
FIG. 3 is a top view showing a numerically controlled turning machine of the spectacle lens manufacturing apparatus of the present invention.
FIG. 4 is a front view showing a copying polishing machine of the spectacle lens manufacturing apparatus of the present invention.
FIG. 5 is a front view showing a numerically controlled polishing machine of the spectacle lens manufacturing apparatus of the present invention.
FIG. 6 is a production range table showing a general production range of spectacle lenses.
[Explanation of symbols]
101 Host computer
102 Calculation process
103 Semi-finished lens selection process
104 Semi-finished lens measurement necessity judgment process
105 Measurement and calculation process of semi-finished lens
106 Shape creation process
107 Polishing necessity judgment process
108 Polishing process
109 Inspection process
201 work
202 Work chuck
203 Workpiece rotating shaft drive motor and encoder
204 Work rotation axis
205 X-axis positioning means
206 X-axis drive motor and encoder
207 beds
208 Y-axis positioning means
209 Y-axis drive motor and encoder
210 Z-axis column
211 Z-axis drive motor and encoder
212 Z-axis positioning means
213 Cutting tool rotating means
214 Blade rotation axis
215 circular cutter
216 Work axis rotation means
301 work
302 Work chuck
303 Work rotation shaft drive motor and encoder
304 X-axis drive motor and encoder
305 X-axis positioning means
306 Work axis rotation means
307 bytes
308 Y-axis positioning means
309 Y-axis drive motor and encoder
310 beds
311 Turret
401 Work
402 Work chuck
403 Workpiece rotation axis
404 Sheet with flexibility
405 Polisher head housing
406 Gas such as compressed air or liquid such as water
407 Polisher head rotation center axis
408 Swing direction
409 Water injection method
410 Polisher head
411 polishing
liquid
501 Work
502 Work chuck
503 Turntable with built-in motor and encoder
504 R-axis positioning means
505 X-axis positioning means
506 X-axis drive motor and encoder
507 Y-axis positioning means
508 beds
509 Y-axis drive motor and encoder
510 Polisher head
511 Polisher head rotating means
512 Z-axis positioning means
513 Load applying means
514 Z-axis drive motor and encoder
515 Load transmission shaft

Claims (2)

NC shape creation process in which machining of a semi-finished lens for molding a spectacle lens is performed based on numerical control machining data processed in consideration of the condition of the spectacle lens wearer, and the NC shape creation process A method of manufacturing a spectacle lens having a copy polishing step performed by copying and polishing the semi-finished lens surface that has been machined in step,
Before performing the NC shape creation step, after selecting a semi-finished lens suitable for machining based on the numerical control machining data, measure the shape of the surface to be processed of the semi-finished lens, A spectacle lens manufacturing method comprising: a correction step of calculating a reference curve for obtaining a desired lens power from the measurement result, and correcting the numerical control processing data based on the calculation result. In claim 1, in the NC shape creation step, the step amount near the inflection point generated when machining is performed is 0.0005 mm or more and 0.005 mm or less excluding the surface roughness component, In addition, the spectacle lens manufacturing method is characterized in that the semi-finished lens is machined so that the maximum surface roughness Rmax of the machined surface is 0.001 mm or more and 0.010 mm or less. .

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