JP2007051895A - Method and instrument for measuring outline shape of lens for eye - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a novel outline shape measuring method for a lens for an eye capable of measuring easily and precisely an outline shape of the lens for the eye such as a contact lens, and capable of precluding the lens for the eye from being damaged when measured. <P>SOLUTION: The lens 12 for the eye is immersed into water 60, and the lens 12 for the eye is irradiated with parallel lights to acquire projection information. The outline shape of the lens for the eye is measured, based on the acquired projection information. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to a method for measuring the outer shape of an ophthalmic lens and a measuring apparatus used therefor.

  In an ophthalmic lens such as a contact lens or an intraocular lens, it may be necessary to measure an outer shape such as a front curve or an edge shape. For example, in the research and development stage of an ophthalmic lens, the outer shape of a prototype ophthalmic lens may be measured to confirm whether an ophthalmic lens having a desired shape can be manufactured. In addition, on the production line, for the purpose of quality control, it is conceivable that the outer shape of the ophthalmic lens is sampled or inspected. Furthermore, in the medical field, it is conceivable to measure the outer shape of the ophthalmic lens in order to confirm whether it conforms to the prescribed one.

  Incidentally, the ophthalmic lens has a small size, and high accuracy is required when measuring the outer shape. Also, many are made of a soft material such as a soft contact lens and are easily deformed. Under such circumstances, it is not easy to measure the outer shape of the ophthalmic lens. In consideration of such circumstances, several methods have been proposed in the past for measuring the outer shape of a contact lens or the like.

  First, as a method conventionally employed, there is a method in which an ophthalmic lens serving as a specimen is cut at a desired site to cut a thin slice, and the slice is enlarged and projected. However, the work of cutting out a soft ophthalmic lens into a thin wall requires considerable skill, the work is troublesome and takes time, and a special solidification process is also required for hydrous materials and soft materials. Also, the cutting position varies, and the cut sections are thin and distorted during measurement, so that the measurement accuracy is inevitably lowered. Furthermore, since only the projected outer shape can be obtained, when confirming the measured outer shape, the design drawing is only overlapped with the projected image and visually confirmed. Therefore, numerical evaluation is performed. Measurement errors due to individual differences are likely to occur. Furthermore, since it is necessary to destroy the specimen when measuring the outer shape, and the specimen must be discarded after the measurement, it cannot be applied to an ophthalmic lens shipped as a product.

  Therefore, in order to deal with the problem of the shape measuring method that has been conventionally employed, for example, Patent Document 1 proposes a contact type outer shape measuring method using a pressing element. However, it goes without saying that it is not preferable to bring the pressing element into contact with a fragile ophthalmic lens, and if it is a prototype in research and development, it cannot be applied to a lens on a production line shipped as a product. . In addition, a soft contact lens or the like that is easily deformed has a problem that it cannot be obtained with an accurate measurement value due to deformation due to contact pressure.

  In view of such problems, for example, Patent Document 2 and Patent Document 3 propose non-contact measurement methods using ultrasonic waves. However, since the speed of sound is easily affected by temperature, strict temperature management is required to maintain the required measurement accuracy, and the equipment becomes expensive. In particular, when measuring an ophthalmic lens formed of a water-containing material in a state of being immersed in water, it is almost impossible to eliminate temperature unevenness in water, and measurement errors are inevitable. In addition, when the ultrasonic transducer is moved in water, the liquid in which the ophthalmic lens is immersed moves to generate undulations or shake the ophthalmic lens, which further increases the measurement error. In addition, to measure the external shape using ultrasonic waves, it is necessary to obtain shape information by calculation from measured values such as distance, so the processing is cumbersome and time consuming, and calculation errors may occur. is there.

  On the other hand, Patent Documents 4 to 6 also propose measurement methods that use laser autofocus or confocal laser to focus on the surface of the specimen and measure the shape based on the amount of movement of the specimen or optical device. Has been. However, all of these measurement methods use light reflected from the specimen, and an ophthalmic lens whose surface is a curved surface such as a spherical surface is sufficient in combination with its translucency. It is difficult to obtain a stable amount of reflected light. In particular, in an ophthalmic lens made of a water-containing material or a soft material, if it is measured in a state where it is immersed in water, the amount of reflected light becomes more difficult to obtain due to attenuation or scattering of the laser in water. . In addition, each of these measurement methods requires a special operation of searching for the focus by scanning with a microscope in order to match the focus position of the measurement optical system with the surface of the specimen using reflected light. . For this reason, there is a problem in that it takes time to learn the operation and takes time.

  As described above, any of the methods for measuring the outer shape of an ophthalmic lens that has been conventionally adopted or proposed has a serious problem with respect to the required ease of operation, measurement accuracy, and the like. Therefore, there is currently no method for measuring the external shape of an ophthalmic lens including a water-containing material or a soft material with high accuracy and ease.

JP-A-5-45249 JP-A-2-52207 Special table 2003-519787 gazette Japanese Patent Laid-Open No. 9-229819 JP 2002-250621 A JP 2000-146532 A

  Here, the present invention has been made in the background as described above, and the problem to be solved is an ophthalmic lens that can quickly perform accurate measurement without damaging the lens. It is to provide a novel external shape measuring method.

It is another object of the present invention to provide an ophthalmic lens outer shape measuring apparatus having a novel structure that is preferably used in such a new outer shape measuring method.

  Hereinafter, embodiments of the present invention made to solve the above-described problems will be described. In addition, the component employ | adopted in each aspect as described below is employable by arbitrary combinations as much as possible. In addition, aspects or technical features of the present invention are not limited to those described below, but are based on the entire specification and drawings, or based on the inventive concept that can be grasped by those skilled in the art from these descriptions. It should be understood that

(Aspect 1 of the present invention relating to an outer shape measuring method of an ophthalmic lens)
That is, Aspect 1 of the present invention relating to the outer shape measuring method of the ophthalmic lens is a method for measuring the outer shape of the ophthalmic lens, in which the ophthalmic lens is immersed in water and a measurement light beam made of parallel light is supplied to the ophthalmic lens. The projection information of the ophthalmic lens is obtained by irradiating the lens, and the outer shape of the ophthalmic lens is measured based on the projection information.

  According to the outer shape measuring method according to this aspect, it is possible to quickly solve the above-mentioned problems of the conventional outer shape measuring method and to quickly obtain accurate measured values without damaging the ophthalmic lens. I can do it.

  First, since it is a non-contact non-destructive inspection for the ophthalmic lens, the ophthalmic lens is not damaged, and it is not necessary to discard the ophthalmic lens after the measurement. As a result, for example, after the ocular lens is inspected by applying the outer shape measuring method to a production line, the ophthalmic lens itself can be shipped as a product. Alternatively, focusing on a specific ophthalmic lens, a change in the shape of the ophthalmic lens before and after various processing steps such as processing and inspection can be tracked.

  In addition, according to the outer shape measuring method of this aspect, the specimen is measured only by measuring the dimensions from the projection information based on the shadow formed by blocking or refracting the measurement light beam made of parallel light by the ophthalmic lens as the specimen. Can be obtained. Therefore, it is not necessary to perform complicated calculation or correction from the measurement value as in the conventional measurement method using ultrasonic waves, and the outer dimensions can be obtained accurately and promptly. Furthermore, since the high-precision management of the environment such as the temperature required by the conventional measurement method using ultrasonic waves is not required, the equipment of the measurement environment becomes simple, and the eye is cheaper. It is possible to measure the external shape of the lens for use.

  Furthermore, even when compared with conventional laser measurement methods using reflected light, projection information can be obtained efficiently by directly receiving the irradiated light, not the reflected light, etc. It can be obtained with high accuracy, and highly accurate shape measurement is realized. In particular, even in the case of water-containing ophthalmic lenses that need to be measured while the specimen is immersed in water, it is possible to avoid a decrease in the light reception level due to light attenuation or scattering, which is a problem in measurement. Shape measurement can be realized. Further, since it is not necessary to focus as compared with the conventional laser measurement method, the operation during the measurement operation is facilitated, and the measurement can be performed quickly.

  Note that the outer shape of the ophthalmic lens in the present embodiment indicates the entire outer surface of the ophthalmic lens including the edge portion, but the entire outer shape of the ophthalmic lens does not necessarily have to be measured. For example, it is of course possible to measure only the outer shape of a specific part such as the optical part, the edge part, or the peripheral part, or to measure only one lens surface in the optical axis direction.

(Aspect 2 of the present invention relating to a method for measuring the outer shape of an ophthalmic lens)
Aspect 2 of the present invention relating to the outer shape measuring method of the ophthalmic lens is the ophthalmic lens outer shape measuring method according to the first aspect, wherein a slit-like light beam is used as the measurement light beam, and the measurement light beam is directed in the slit width direction. The projection information of the ophthalmic lens is obtained at a plurality of positions by moving the ophthalmic lens relative to the ophthalmic lens.

  In this aspect, the use of the slit-shaped measurement light beam facilitates alignment of the ophthalmic lens with the measurement light beam in the slit longitudinal direction. In addition, by moving the measurement light beam relative to the ophthalmic lens in the slit width direction, the shape can be measured even if the slit width is reduced, which makes it possible to simplify and simplify the laser irradiation device. Become. In this aspect, it is preferable that the device that receives the measuring device while facing the measuring beam irradiation device is also moved relative to the ophthalmic lens in the slit width direction together with the irradiation device. Thereby, not only the laser irradiation device but also the light receiving device can be sufficiently downsized in the slit width direction.

  In this measurement method, movement is not limited to either the ophthalmic lens or the measurement beam, but the measurement beam is moved while the ophthalmic lens is supported in a fixed position. Is desirable. As a result, the liquid in which the ophthalmic lens is immersed can be prevented from moving and causing ripples or shaking of the ophthalmic lens, and a decrease in measurement accuracy due to such a phenomenon can be avoided. It becomes.

(Aspect 3 of the present invention relating to an outer shape measuring method of an ophthalmic lens)
Aspect 3 of the present invention relating to the outer shape measuring method of the ophthalmic lens is the ophthalmic lens outer shape measuring method according to the second aspect, wherein a slit-like light beam extending parallel to the central axis of the ophthalmic lens is used as the measuring light beam. And irradiating the measurement light beam from the side of the ophthalmic lens, moving the measurement light beam relative to the ophthalmic lens in a direction orthogonal to the central axis of the ophthalmic lens, and performing the projection It is characterized in that the position interval for obtaining information is varied in a plurality of stages in the relative movement direction of the measurement light beam and the ophthalmic lens.

  According to this aspect, by acquiring the projection information at a plurality of positions while moving the slit-shaped light flux extending in parallel with the central axis of the ophthalmic lens relative to the ophthalmic lens in the slit width direction, An external shape that can be observed in a side view such as a vertical cross-sectional shape of the ophthalmic lens can be measured from the obtained projection information. Therefore, by changing the distance interval of the projection information acquisition position as necessary, for example, in a region where the shape change is large, the projection information is acquired at a fine distance interval, while in a region where the shape change is small, a large distance interval is obtained. In this way, it is possible to simplify the operation and shorten the work time while maintaining the shape measurement accuracy by acquiring projection information.

(Aspect 4 of the present invention relating to an outer shape measuring method of an ophthalmic lens)
Aspect 4 of the present invention relating to an ophthalmic lens outer shape measuring method is the ophthalmic lens outer shape measuring method according to any one of the first to third aspects, wherein the ophthalmic lens is a contact lens and has a convex surface. The contact lens facing upward is supported from below, so that the convex surface of the contact lens is exposed throughout the water, and the contact lens is irradiated with the measurement light beam. To do.

  According to this aspect, since the entire convex surface of the contact lens can be exposed and positioned and held in water, projection information can be easily obtained for various portions of the convex surface of the contact lens by irradiation with the measurement light beam. It becomes possible.

(Aspect 5 of the present invention relating to a method for measuring the outer shape of an ophthalmic lens)
Aspect 5 of the present invention relating to an outer shape measuring method for an ophthalmic lens is an ophthalmic lens outer shape measuring method according to any one of the first to fourth aspects, wherein the outer shape of the ophthalmic lens is approximated from the projection information. The measurement shape of the ophthalmic lens is obtained by specifying with a curve.

  According to this aspect, the measurement result of the outer shape of the ophthalmic lens can be expressed by a mathematical expression. Therefore, it is possible to grasp and analyze the outer shape of the ophthalmic lens and compare it with a target shape by mathematical processing. As a result, various determinations such as success / failure based on the measurement result of the outer shape can be objectively performed, and the use range and the degree of freedom of the measurement result are increased. As an approximation method for obtaining such an approximate curve, various approximation methods such as least square approximation and spline approximation are appropriately employed.

(Aspect 6 of the present invention relating to an outer shape measuring method of an ophthalmic lens)
Aspect 6 of the present invention relating to an ophthalmic lens outer shape measuring method is the ophthalmic lens outer shape measuring method according to any one of the first to fifth aspects, wherein the outer shape of the ophthalmic lens is specified from the projection information. Thus, the measurement shape of the ophthalmic lens is obtained, and the obtained measurement shape is compared with the design shape of the ophthalmic lens.

  According to this aspect, based on the measurement result of the outer shape of the ophthalmic lens obtained according to the method of the present invention, it is possible to easily and accurately grasp errors that occur in manufacturing. In addition, the comparison method in this aspect is not limited. For example, in addition to adopting the approximate curve obtained according to the aspect 5, for example, the measurement drawing obtained by measuring the outer shape is superimposed on the design drawing. A visual comparison may be used. At that time, only a specific part of the ophthalmic lens may be measured, and the external shape of the specific part may be compared with the design shape.

(Aspect 7 of the present invention relating to an outer shape measuring method of an ophthalmic lens)
Aspect 7 of the present invention relating to the outer shape measuring method of the ophthalmic lens is characterized in that, in the outer shape measuring method of the ophthalmic lens according to any one of the first to sixth aspects, a laser beam is used as the measuring light beam. To do.

  According to this aspect, attenuation of the measurement light beam in water can be sufficiently suppressed, and the straightness of the measurement light beam can be maintained at a higher level. Therefore, more accurate and stable shape measurement can be realized.

(Embodiment 8 of the present invention relating to an outer shape measuring method of an ophthalmic lens)
Aspect 8 of the present invention relating to an ophthalmic lens outer shape measuring method is the ophthalmic lens outer shape measuring method according to any one of the first to seventh aspects, wherein the ophthalmic lens is a contact lens, and the projection The shape of the convex surface of the contact lens is specified from the information, the thickness dimension of the contact lens is measured, and based on the shape of the convex surface specified from the projection information and the thickness dimension obtained by the measurement, It is characterized by measuring the shape of the concave surface of the contact lens.

  According to this aspect, the concave shape of the contact lens that is difficult to obtain shape information directly by projection can be obtained with high accuracy based on the projection information. That is, in this aspect, since the outer shape of the contact lens can be obtained with high accuracy directly from the projection information, the measurement information of the thickness dimension of the contact lens at an appropriate part is added to the outer shape, thereby adding the lens. The inner surface shape can be obtained with high accuracy. As a method for measuring the thickness dimension, a conventionally known method can be appropriately employed. For example, a presser is used, a lens section is created and projected, or measurement is performed using laser reflected light. Etc., and the thickness can be measured. In addition, as a measuring method in the thickness direction, a method of measuring the thickness dimension in the optical axis direction and a method of measuring the thickness dimension in the normal direction of the lens surface can be adopted. By specifying the inner surface shape in consideration, it is possible to obtain a highly accurate inner surface shape in any case.

(Aspect 1 of the present invention relating to an external shape measuring apparatus for an ophthalmic lens)
Aspect 1 of the present invention relating to an ophthalmic lens outline measuring apparatus is an ophthalmic lens outline measuring apparatus suitably used in carrying out the ophthalmic lens outline measuring method according to the present invention described in the above embodiments. And a storage case having a storage region for storing water and provided with support means for supporting the ophthalmic lens in water in the storage region, and one side opposite to the storage case Is provided with measurement light irradiation means for irradiating the measurement light beam, and on the other side of the storage case is provided measurement light light reception means for receiving the measurement light beam, and in the storage case The side wall portion on the irradiation side of the measurement light beam and the side wall portion on the light receiving side of the measurement light beam are both formed into a translucent flat plate shape that extends perpendicular to the irradiation direction of the measurement light beam. Special To.

  In the external shape measuring apparatus having the structure according to the present invention, since the incident and exit of the measurement light beam with respect to the housing case are both in the vertical direction, reflection and refraction when the measurement light beam enters and exits the housing case and water. Can be suppressed. Therefore, the amount of received light can be obtained more advantageously, the measurement stability can be improved, and the measurement error due to refraction can be suppressed, thereby further improving the measurement accuracy. It should be noted that the surface that intersects the measurement light beam in the housing case is sufficient if at least the portion where the measurement light beam is incident and exited is formed perpendicular to the measurement light beam, and the entire surface is formed perpendicularly. There is no need to be. Moreover, it is possible to prevent a measurement error due to light incident from the outside by making the housing case opaque except for a portion where the measurement light beam is incident and exited.

(Aspect 2 of the present invention relating to an external shape measuring apparatus for an ophthalmic lens)
Aspect 2 of the present invention relating to an ophthalmic lens outer shape measuring apparatus is the ophthalmic lens outer shape measuring apparatus according to the first aspect described above, wherein the adjustment base base for supporting the housing case is at least one that moves in three orthogonal directions. It is characterized in that a device provided with a position adjusting mechanism for adjusting the tilt around the axis is provided.

  In this aspect, it is possible to easily change and adjust the irradiation direction of the measurement light beam on the ophthalmic lens. Thereby, the measurement site | part in an ophthalmic lens, ie, the object direction which acquires projection information, can be adjusted easily. In particular, since the tilt around one axis can be adjusted, the degree of freedom of adjustment is great. When the coordinate system of three orthogonal axes of X, Y, and Z is taken into consideration, the tilt applied to the movement of each of the X, Y, and Z axes includes a roll around the X axis and a pitch around the Y axis. , Yaw displacement around the Z axis is considered. The tilt in these three directions can all be adjusted, so that the eye can be adjusted without changing the projection direction of the measurement light beam and without changing the position of the irradiation device or light receiving device of the measurement light beam. It is possible to adjust and set the projection direction of the measurement light beam onto the lens for use substantially arbitrarily.

(Aspect 3 of the present invention relating to an external shape measuring apparatus for an ophthalmic lens)
Aspect 3 of the present invention relating to an ophthalmic lens outer shape measuring apparatus is the ophthalmic lens outer shape measuring apparatus according to the first or second aspect, wherein the measuring light irradiating means and the measuring light irradiating means arranged opposite to each other across the housing case An optical system moving means is provided for horizontally moving the measuring light receiving means in a state where the housing case is fixed in position while maintaining a certain mutual opposed arrangement state.

  In this aspect, the measurement light beam is prevented while avoiding measurement errors due to misalignment of the measurement light beam irradiation device and the light receiving device, and avoiding the spilling water of the storage case and the displacement of the ophthalmic lens as much as possible. The irradiation position with respect to the ophthalmic lens can be gradually moved to obtain a plurality of positions. Thereby, the projection information of the ophthalmic lens can be easily obtained with higher accuracy. In particular, the apparatus according to this aspect can be more advantageously employed when implementing the aspect 2 or 3 of the present invention relating to the above-described measurement method.

(Aspect 4 of the present invention relating to an external shape measuring apparatus for an ophthalmic lens)
Aspect 4 of the present invention relating to an ophthalmic lens outer shape measuring apparatus is the ophthalmic lens outer shape measuring apparatus according to any one of the first to third aspects, wherein the support means is provided in the accommodating area of the accommodating case. And a support protrusion protruding upward from below, and the ophthalmic lens is placed on and supported by the protruding tip of the support protrusion. The width dimension of the protruding tip portion on which the ophthalmic lens is placed is set to be smaller than the outer dimension of the ophthalmic lens at least in the horizontal direction perpendicular to the irradiation direction of the measurement light beam. The outer peripheral edge of the ophthalmic lens is projected outward from the projecting tip of the support projection on both sides in the width direction of the projecting tip of the support projection under the support state of the lens for use. This is a feature.

  In this aspect, the edge portion on the outer periphery of the ophthalmic lens can be exposed to water on both sides in the width direction orthogonal to the irradiation direction of the measurement light beam, and the edge portion abuts on the support protrusion and the like and deforms. Or a shadow on the support protrusion or the like is avoided. Thereby, the projection information by the measurement light beam can be efficiently obtained in a sufficiently wide region even at the edge portion of the ophthalmic lens. That is, by placing the ophthalmic lens on the support protrusion having the structure according to this aspect, for example, the vertical cross-sectional shape passing through the central axis of the ophthalmic lens by the measurement light beam irradiated from the side is used as the projection information. Based on this, it becomes possible to make an advantageous measurement.

In addition, the support protrusion is provided with a notch in the outer peripheral portion located on both sides in the width direction, for example, so that when the ophthalmic lens is placed, light passing through the edge of the ophthalmic lens is blocked or refracted. It can be formed in such a way. However, the specific shape of the support protrusion can be variously set according to the shape of the ophthalmic lens to be measured, the measurement site, and the like.

  As is apparent from the above description, according to the method of the present invention, the outer shape of the ophthalmic lens as a specimen can be easily and highly increased regardless of whether it is a hydrous lens or a non-hydrous lens without destroying or damaging the ophthalmic lens. It becomes possible to measure with high accuracy.

Moreover, according to the apparatus of the present invention, such a method of the present invention can be more advantageously carried out.

  Hereinafter, in order to clarify the present invention more specifically, embodiments of the present invention will be described in detail with reference to the drawings.

  First, FIG. 1 shows an external shape measuring apparatus 10 used for external shape measurement of an ophthalmic lens according to the present invention. The external shape measuring apparatus 10 moves in a uniaxial direction above a support device 14 as an adjustment base base that supports a contact lens (hereinafter referred to as a lens) 12 as an ophthalmic lens as a specimen so that the position of the contact lens 12 can be adjusted. And a dimension measuring device 16 arranged in a possible manner. In the following description, the vertical direction means the vertical direction in FIG. 1 in principle. 1 is defined as an X-axis direction, a horizontal direction in FIG. 1 is a Y-axis direction, and a vertical direction in FIG. 1 is a Z-axis direction. That is, these X, Y, and Z are axes of an orthogonal triaxial coordinate system, with the X and Y axes extending in the horizontal direction and the Z axis extending in the vertical direction.

  2 and 3 show the support device 14. The support device 14 has a structure in which an inclination stage 18, a rotation stage 20 and a YZ axis stage 22 are stacked, and a cell 23 as an accommodation case for accommodating the lens 12 is disposed on the YZ axis stage 22 positioned at the uppermost stage. It is placed. The position of the lens 12 accommodated in the cell 23 can be adjusted by operating the tilt stage 18, the rotary stage 20, and the YZ axis stage 22.

  The tilt stage 18 has a structure in which a plate-like tilt mounting portion 26 having substantially the same dimensions as the base 24 is attached to a base 24 having a substantially rectangular block shape so as to be tiltable. . The base 24 is provided with a Y-axis tilt knob 28 protruding in the X-axis direction and an X-axis tilt knob 30 protruding in the Y-axis direction. By rotating the Y-axis tilting knob 28, the tilt mounting portion 26 is tilted with the end on the side where the X-axis tilting knob 30 is provided about the axis extending in the Y-axis direction, while the X-axis tilting is performed. By rotating the knob 30, the inclined mounting portion 26 can be tilted about the axis extending in the X-axis direction at the end on the side where the Y-axis tilting knob 28 is provided. As such a tilting stage 18, a commercially available tilting stage can be appropriately employed. For example, a tilting stage B41-61AN manufactured by Suruga Seiki Co., Ltd. is preferably employed.

  The rotation stage 20 is attached to the inclination mounting portion 26 of the inclination stage 18. The rotary stage 20 is attached to a substantially rectangular block-shaped base 32 that is substantially square in a top view so that a disk-shaped rotational mounting portion 34 having a diameter dimension substantially equal to one side of the base 32 can be rotated. The rotation mounting portion 34 is rotatable about an axis extending in the Z-axis direction through the center thereof. A large rotation operation of the rotation mounting portion 34 can be performed by operating a coarse movement knob 35 provided on the rotation mounting portion 34, and a coarse movement clamp 36 provided on the rotation mounting portion 34 is provided. By operating, the large rotation of the rotation mounting portion 34 can be fixed. Further, the base 32 is provided with the fine movement knob 38 and the fine movement clamp 40 facing each other. By rotating the fine movement knob 38, the minute rotational position of the rotation mounting portion 34 can be adjusted. In addition, by operating the fine movement clamp 40, the rotational position of the rotation mounting portion 34 can be fixed. As such a rotary stage 20, a commercially available rotary stage can be appropriately employed. For example, a rotary stage B43-60N (trade name) manufactured by Suruga Seiki Co., Ltd. is preferably used.

  The YZ axis stage 22 is attached to the rotation attachment portion 34 of the rotation stage 20. The YZ-axis stage 22 has a generally rectangular block shape as a whole, and a plate-like lower mounting plate portion 42 is provided at the lower end portion, while a plate-like upper mounting plate portion 44 is arranged at the upper end portion. It is installed.

  A base portion 46 is fixedly attached to the lower attachment plate portion 42, and a Y-axis moving portion 48 is attached to the base portion 46 so as to be relatively displaceable in the Y-axis direction. The Y-axis moving part 48 is configured to move in the Y-axis direction with respect to the base part 46 by rotating the Y-axis feed knob 50 protruding from the base part 46.

  Further, on the opposite side of the base 46 of the Y-axis moving part 48, a Z-axis moving part 52 is attached so as to be relatively displaceable in the Z-axis direction. The Z-axis moving part 52 can be moved in the Z-axis direction with respect to the Y-axis moving part 48 by rotating the Z-axis feed knob 54 protruding from the Y-axis moving part 48. Yes.

  That is, the YZ-axis stage 22 is configured such that the upper mounting plate portion 44 is displaced in the YZ-axis direction by rotating the Y-axis feed knob 50 and the Z-axis feed knob 54. As such a YZ-axis stage 22, a commercially available XZ-axis stage that can be displaced in two orthogonal axes can be used as appropriate. For example, an XZ-axis ant stage B09-37U manufactured by Suruga Seiki Co., Ltd. is suitable. Adopted.

  A cell attachment portion 56 is attached to the upper attachment plate portion 44 of the YZ axis stage 22. The cell mounting portion 56 has a substantially rectangular block shape having a size substantially equal to that of the upper mounting plate portion 44 in a top view, and is opened upward at a center portion of the top surface with a size substantially equal to the lower end surface of the cell 23. An upper opening 58 is formed. The cell 23 can be attached to the upper opening 58 so as to be inserted.

  As is clear from FIG. 2, the cell 23 is formed in a rectangular tube shape having a bent bottom that is open at the upper side and curved at the lower edge, and is attached to the support device 14 in the Y-axis direction. A pair of side surfaces 59a as a side wall portion on the irradiation side and a side surface 59b as a side wall portion on the light receiving side are formed in parallel with each other. In the state of being attached to the support device 14, the side surfaces 59a and 59b are arranged so as to extend in parallel with the Z-axis direction and are arranged perpendicular to the Y-axis direction. . The side surfaces 59a and 59b are both transparent so that parallel light can be transmitted.

  The inside of the cell 23 is a storage area for storing water and is filled with a predetermined amount of saline 60, and a jig 62 as a support means for the ophthalmic lens on which the lens 12 is placed is attached to the saline 60. It is accommodated in the cell 23 in a soaked state.

  Such a jig 62 is shown in FIGS. The jig 62 is configured by extrapolating an extrapolating member 68 having a substantially rectangular outer shape to a substantially cylindrical cylindrical portion 66 having a through hole 64 extending in the axial direction.

  A diameter-enlarged portion 70 having a larger diameter is formed at a substantially central portion in the axial direction of the cylindrical portion 66, so that a first protrusion as a support protrusion is formed at the upper edge of the diameter-enlarged portion 70. A stepped portion 72 is formed. Furthermore, the lower end part of the enlarged diameter part 70 is extended outward, and the 2nd level | step-difference part 74 is formed by this. Further, a pair of notches 76 and 76 that are parallel to each other and extend linearly are formed at both ends in the width direction between the first stepped portion 72 and the second stepped portion 74 in the enlarged diameter portion 70. Has been.

  Then, the extrapolation member 68 is inserted from above the cylindrical portion 66, locked by the second stepped portion 74, and aligned in the circumferential direction by the notches 76, 76. 68 is assembled to the substantially central portion in the axial direction of the cylindrical portion 66 so that the edge thereof is substantially parallel to the notches 76 and 76.

  The lens 12 is placed above the jig 62 having such a structure. The lens 12 is placed on the jig 62 with the peripheral edge thereof supported from below by the first stepped portion 72 of the jig 62 in a convex upward direction. Here, since the pair of notches 76 and 76 are formed in the enlarged diameter portion 70, the width dimension in the front view is slightly smaller than the diameter dimension of the lens 12. The stepped portion 72 is supported at a portion where the notches 76, 76 are not formed, and at the portion where the notches 76, 76 are formed, the edge portion (edge portion) of the stepped portion 72 with respect to the enlarged diameter portion 70. Thus, it is placed in a non-contact and protruding outward state. Thereby, the convex surface of the outer surface of the lens 12 is exposed throughout. Further, as apparent from FIG. 4, the lens 12 is placed in a non-contact state with a slight gap between the inner surface of the lens 12 and the upper edge of the cylindrical portion 66. When the lens 12 is excessively displaced, the upper end edge of the lens is engaged with the lens 12 to limit the excessive displacement.

  Then, the jig 62 is accommodated inside the cell 23 with the lens 12 placed thereon, and the entire jig 62 including the lens 12 is immersed in the saline 60 filled in the cell 23. Yes. Here, since the jig 62 is provided with the through hole 64, the jig 62 can be easily pushed into the bottom of the cell 23 filled with the saline 60. Further, the outer shape of the extrapolation member 68 of the jig 62 in a top view is substantially the same as the opening shape of the cell 23, whereby the jig 62 is positioned in the cell 23 so as not to rotate in the circumferential direction. The notches 76 and 76 are accommodated in a state extending in the Y-axis direction. That is, the pair of notches 76 and 76 are formed so as to face each other in the X-axis direction.

  The lens 12 is supported by the support device 14 as described above. The lens 12 can be finely adjusted by the tilt stage 18, the rotary stage 20, and the YZ axis stage 22 of the support device 14 with respect to the tilt position, the rotation position about the Z axis, and the position in the YZ axis direction. Has been.

  Above the support device 14 having such a structure, a dimension measuring device 16 is arranged in a non-contact spaced state from the support device 14. The dimension measuring device 16 is attached to an X-axis stage 80 as an optical system moving means assembled to a portal-shaped height adjustment platform 78 and is movable in the X-axis direction.

  More specifically, the height adjustment platform 78 is a gate-shaped member in which a plate-like beam portion 84 is supported by a pair of support legs 82 and 82. Here, the height dimensions of the support legs 82 are substantially the same as the height position of the lens 12 supported by the support device 14 at the height positions of the light projecting portion 96 and the light receiving portion 98 of the dimension measuring device 16 described later. While being adjusted to be equal, the dimension of the beam portion 84 in the Y-axis direction is made larger than the dimension of the dimension measuring device 16 in the Y-axis direction. In addition, as the height adjustment platform 78, a commercially available height adjustment platform can be appropriately employed. For example, a height adjustment platform E11B-h manufactured by Suruga Seiki Co., Ltd. is preferably employed.

  The X-axis stage 80 is attached to an attachment plate member 86 provided on the lower surface of the beam portion 84 of the height adjustment platform 78. 6 and 7 show the X-axis stage 80 with the dimension measuring device 16 attached thereto. The X-axis stage 80 has a plate-like base 88 having a width dimension substantially equal to the width of the base 88 and a length dimension slightly smaller than the base 88 in the X-axis direction. The movable plate 90 is attached to be movable in the X-axis direction, and can be driven and displaced in the X-axis direction by a drive motor 92 assembled to the base 88. The driving of the drive motor 92 is electrically controlled by a controller (not shown) connected to the connector 94, whereby the moving amount and moving speed of the moving plate 90 in the X-axis direction are electrically controlled. It is possible to control. As such an X-axis stage 80, a commercially available automatic X-axis stage can be appropriately employed. For example, an automatic X-axis stage KS101-30LMS manufactured by Suruga Seiki Co., Ltd. is preferably employed.

  The dimension measuring device 16 is attached to the moving plate portion 90 of the X-axis stage 80. The dimension measuring device 16 is an optical dimension measuring device, and a sample is disposed between a light projecting unit 96 and a light receiving unit 98 as a light source, and is received by parallel light emitted from the light projecting unit 96. The shape of the shadow of the specimen projected on the unit 98 is measured.

  Specifically, as shown in FIG. 8, the light projecting unit 96 is provided with a light emitting device 100 as measurement light irradiating means for irradiating parallel light. A measurement light beam having an appropriate size and shape is irradiated. The light emitting device 100 only needs to project parallel light toward the light receiving unit 98. For example, the light emitting device 100 may be configured by combining a laser, a slit, or a light emitting source such as an LED and a collimator lens.

  In particular, in the present embodiment, such a measurement light beam has a vertically long slit-shaped cross-sectional shape that linearly extends in the vertical direction with a small width. The width direction of the measurement light beam is the horizontal direction (X-axis direction), and the longitudinal direction of the measurement light beam is the vertical direction (Z-axis direction).

  On the other hand, a light receiving unit 98 is disposed opposite to the light projecting unit 96 at a position separated from the light projecting unit 96 in the traveling direction of parallel light emitted from the light projecting unit 96. Inside the light receiving unit 98, there is provided a light receiving device 102 as an irradiation surface constituted by, for example, a CCD or the like as a measurement light receiving unit that receives parallel light emitted from the light projecting unit 96.

  Then, a specimen (lens 12 in the present embodiment) is disposed between the opposing surfaces of the light projecting unit 96 and the light receiving unit 98, and parallel light is irradiated from the light projecting unit 96 toward the light receiving unit 98. As a result, the light ray blocked or refracted by the specimen does not reach the light receiving device 102, and only the light ray that is not blocked or refracted by the specimen arrives to project the shadow of the specimen. Projection information is obtained by binarizing the brightness received by the light receiving device 102 with a specific threshold. The projection information of the present embodiment obtained in this way is an electrical signal and is transmitted as digital data to a controller connected to the dimension measuring device 16. Since this projection information basically represents the outer shape information of the specimen as it is, the shape of the shadow of the specimen can be visually recognized as an image on the monitor by monitor display processing. Further, this projection information can be recorded or output as digital data, and can be processed as required.

  Although not shown, the dimension measuring device 16 according to the present embodiment includes a monitor camera inside the light receiving unit 98 and transmits the light beam incident on the light receiving unit 98 to the light receiving device 102 and the monitor camera. A splitting beam splitter is provided so that a part of the light beam incident on the light receiving unit 98 can be received by the monitor camera. Such a monitoring camera is connected to the controller in the same manner as the light receiving device 102, so that the shape of the shadow received by the light receiving device 102 can be viewed in real time on the monitor on the controller. Yes.

  As the dimension measuring device 16 having such a structure, a commercially available optical digital dimension measuring machine can be appropriately employed. For example, a digital dimension measuring machine LS-7010M (trade name) manufactured by Keyence Corporation can be used. Preferably employed.

  The dimension measuring device 16 is attached to the moving plate portion 90 of the X-axis stage 80 and is movable in the X-axis direction. Here, the height position of the dimension measuring device 16 is a height position at which the cell 23 attached to the support device 14 and exposed from the cell attachment portion 56 is positioned between the light projecting portion 96 and the light receiving portion 98. That is, the height dimension of the height adjustment platform 78 is adjusted so that the lens 12 is positioned at a height between the light projecting unit 96 and the light receiving unit 98.

  As described above, the external shape measuring apparatus 10 used for the external shape measurement of the ophthalmic lens according to the present invention is configured. Such an external shape measuring apparatus 10 can measure the external shape of the ophthalmic lens by operating, for example, according to the procedure shown in FIG.

(Step 1)
First, a saline solution adjusted to an appropriate osmotic pressure is adopted as water, and the jig 62 is inserted into the cell 23 filled with the saline solution, and the lens 12 serving as a specimen is convex upward on the jig 62. Place in the direction. And the cell 12 is set in the support apparatus 14 in the state immersed in the salt solution by inserting the cell 23 in the upper side opening part 58 of the cell attachment part 56 in the support apparatus 14. FIG.

(Step 2)
Next, while confirming with a monitor of a controller connected to the dimension measuring device 16, the YZ axis stage 22 of the support device 14 is operated so that the apex of the lens 12 falls within the measurement area of the dimension measuring device 16. In addition, the positions of the lens 12 in the Y-axis and Z-axis directions are adjusted so that the monitor camera provided in the dimension measuring device 16 is focused near the edge of the lens 12. Further, the rotation position of the jig 62 is adjusted by operating the rotary stage 20 so that the direction of the notches 76 and 76 of the jig 62 is parallel to the direction of the parallel light of the dimension measuring device 16. Further, when the lens 12 is greatly inclined with respect to the horizontal direction, the inclination of the lens 12 is adjusted to approach the horizontal by operating the inclination stage 18.

(Step 3)
Subsequently, while confirming with a monitor of a controller connected to the dimension measuring device 16, the X-axis stage 80 is set so that the center of the measurement area of the dimension measuring device 16 is located at a position matching one of the edge portions of the lens 12. To position the position of the dimension measuring device 16 in the X-axis direction at the measurement start position.

(Step 4)
Next, the dimension measuring device 16 irradiates the lens 12 with parallel light from the light projecting unit 96 positioned on the side of the lens 12. Then, the parallel light is blocked or refracted by the lens 12, and the size of the shadow projected on the light receiving unit 98 is measured to obtain a measured value. Such measured values are stored as numerical data in a controller connected to the dimension measuring device 16.

(Step 5)
Subsequently, with the cell 23 being fixed in position, the X-axis stage 80 is operated by one step to move the dimension measuring device 16 in the X-axis direction by a predetermined distance (in this embodiment, one step is 0.01 mm). .

(Step 6)
The dimension measuring device 16 moved in the X-axis direction repeats step 4 and step 5 until it passes the other edge portion of the lens 12, and measures the outer shape of the lens 12 at each measurement position. When the dimension measuring device 16 passes the other edge portion of the lens 12, the measurement is completed.

  As described above, the outer shape of the lens 12 can be obtained. And according to the external shape measuring method in this embodiment, since the external shape can be measured with respect to the lens 12 without contact, there is no possibility of damaging the lens 12. Therefore, the lens that is shipped as a product is directly inspected by tracking changes over time before and after various tests for a specific lens, or by applying this measurement method on the production line, and more thorough. Quality control can also be performed.

  Furthermore, according to the outer shape measuring method in the present embodiment, the shadow of the lens 12 projected on the light receiving unit 98 is the outer shape of the lens 12 itself. Therefore, the outer shape of the lens 12 is measured by measuring the size of the shadow. Can be measured. This eliminates the need for calculation and correction for obtaining a measurement value as in the case of using ultrasonic waves, and allows the measurement value to be obtained quickly. In addition, since this measurement method uses light, advanced temperature control is not required, as is the case with ultrasound, and the outer shape of the ophthalmic lens is measured at multiple locations on the production line. Management can also be realized at low cost.

  In particular, in the outer shape measuring apparatus 10 according to the present embodiment, by using the jig 62 having a specific shape, it becomes possible to advantageously perform the outer shape measurement of the ophthalmic lens according to the present measuring method. That is, in the jig 62 in this embodiment, the pair of notches 76 and 76 are formed, so that the edge portion of the lens 12 placed on the jig 62 is viewed from the light projecting unit 96 side. The jig 62 is placed in a non-contact and separated state. Accordingly, it is possible to accurately project the shape of the edge portion of the lens 12 onto the light receiving portion 98 while avoiding that the parallel light emitted from the light projecting portion 96 is blocked or refracted by the jig 62. -ing Further, since the side surface 59a as the side wall portion on the irradiation side and the side surface 59b as the side wall portion on the light receiving side in the cell 23 are formed as a translucent flat plate extending perpendicular to the light beam, the light beam enters and exits. It is also possible to improve measurement stability by suppressing reflection and refraction.

  In addition, in the outer shape measuring apparatus 10 according to the present embodiment, the dimension measuring apparatus 16 is moved after the lens 12 is positioned in the YZ axis direction by operating the YZ axis stage 22 or the like of the support apparatus 14. Thus, the light emitting device 100 that emits parallel light and the light receiving device 102 on which the shadow of the lens 12 is projected are moved in the X-axis direction. Thereby, the lens 12 immersed in water is not moved during the measurement, and it is possible to avoid the liquid moving and affecting the measurement.

  The outer shape of the ophthalmic lens thus obtained is based on, for example, an approximate circle created from two points near both ends of the outer shape and one point near the middle as shown in FIG. The curvature radius and diameter of the ophthalmic lens obtained in this way can be compared with the design value. In addition, in Fig.10 (a), the external shape obtained by applying this measuring method with respect to the jig used when manufacturing an ophthalmic lens, and the approximate circle created based on this external shape are shown, FIG. 10B shows an outer shape obtained by applying this measurement method to an ophthalmic lens manufactured using such a jig, and an approximate circle created based on the outer shape. Here, the straight lines extending in the vertical direction at both ends of the outer shape of the lens in the figure indicate the rise of data at the edge of the outer shape, and so on, as seen upward in the outer shape of FIG. It seems that the protruding part of is a noise mixed at the time of measurement.

  It is also possible to superimpose the outer shape of the ophthalmic lens obtained by the above-described outer shape measuring method with the design design data and compare the outer shape with the design shape. FIG. 11 shows an example of a procedure for comparing the outer shape of the ophthalmic lens obtained by the above measuring method with the design shape.

(Step 1)
First, the outer shape of the ophthalmic lens is measured using the outer shape measuring method as described above, and the measurement value obtained as numerical data is plotted on a computer screen, thereby making a measurement plot of the outer shape of the ophthalmic lens. obtain. Then, the portions considered to be both edges of the measurement plot are connected with a straight line, and the inclination angle with respect to the horizontal line is calculated.

(Step 2)
The measurement plot is rotated around one of the edges corresponding to the inclination angle obtained in step 1, and the measurement plot is corrected horizontally.

(Step 3)
Next, since the size of the ophthalmic lens varies at the time of measurement, the design design data size of the measured ophthalmic lens is enlarged or reduced to fit the measurement plot. Since the ophthalmic lens is deformed in a similar shape, there is no effect even if the design design data is enlarged or reduced.

(Step 4)
Subsequently, a perpendicular line is drawn from the midpoint of a straight line connecting portions that are considered to be both edges of the measurement plot, and the measurement plot is moved so that the intersection of the perpendicular line and the measurement plot coincides with the lens apex of the design design data. Thereby, the measurement plot and the design design data can be fitted.

  FIG. 12A shows an overall view of the lens outer shape and design design data fitted in this way, and FIG. 12B shows an enlarged view of the edge portion of the lens. From FIG. 12, it can be confirmed that the measured outer shape of the ophthalmic lens substantially overlaps the design design data.

  In addition to measuring the outer shape of the ophthalmic lens by this outer shape measuring method, the inner shape of the lens can be obtained by using the outer shape and the thickness distribution by separately measuring the thickness distribution of the ophthalmic lens. . 13 and 14 show a procedure for plotting the inner surface shape from the outer surface shape by measuring the thickness distribution.

(Step 1)
First, the outer shape of the ophthalmic lens is measured using the measurement method as described above, and a measurement plot is prepared in advance. In this procedure, it is necessary to cut the lens in order to measure the lens thickness. The cut lens is easily deformed, and it takes time to measure the outer shape, so a measurement plot is prepared in advance before cutting. It is preferable.

(Step 2)
Then, the ophthalmic lens is cut with a microtome or the like to create a section of the lens.

(Step 3)
Next, the lens slice is projected onto the projector, and the lens slice is set so as to be horizontal with respect to the reference horizontal line h of the projector.

(Step 4)
Subsequently, the reference vertical line v of the projector is aligned with the edge portion of the lens segment.

(Step 5)
Next, the thickness B is measured in the normal direction (appearance) based on the lens outer surface from the point where the reference vertical line v of the projector and the outer surface of the lens intersect. The thickness can be measured, for example, by measuring a shadow projected by a projector using a ruler.

(Step 6)
Then, the reference vertical line v of the projector is shifted in the horizontal direction. Here, the amount of movement of the projector may be varied depending on the part of the lens. For example, the distance from the edge portion of the lens to 1 mm may be moved at 0.1 mm intervals, and thereafter, the lens may be moved to 7.0 mm at 0.5 mm intervals.

(Step 7)
Next, it is checked whether or not the reference vertical line of the moved projector has reached a predetermined measurement end position. If the reference vertical line has not reached the measurement end position, step 5 and step 6 are repeated.

(Step 8)
When the reference vertical line of the projector reaches the measurement end position, the inner surface shape is plotted from the thickness distribution measured at each measurement point based on the lens outer shape plot obtained by the outer shape measuring method according to the method of the present invention. I can do it. Here, since the outer surface shape plot of the lens is easily deformed after the lens is cut, it is desirable to prepare it in advance before cutting the lens.

  In this way, the inner shape of the lens can be obtained effectively. That is, when the thickness dimension of the lens is measured in the optical axis direction, the entire lens is inclined or an error is likely to occur in the measured value depending on the lens arrangement state. However, according to the present measuring method, since the thickness in the normal direction at the measurement point is measured, the influence of deformation or the like due to the arrangement state of the lens is suppressed, and the error can be suppressed small. In addition, for example, in a conventional method for measuring a lens thickness using light, it is difficult to obtain reflected light when the measurement location is away from the center of the lens. However, according to this measurement method, the apparatus can be kept compact.

  In order to reduce the complexity of cutting with a microtome and measuring the projected shadow with a ruler in the thickness measurement procedure described above, the cut surface of the ophthalmic lens cut in half is photographed with a CCD. Then, it may be processed by a computer.

  As mentioned above, although one Embodiment of this invention has been described, this is an illustration to the last, Comprising: This invention is not limited at all by the specific description in this Embodiment.

  For example, as the specific shape of the lens mounting table on which the lens 12 is mounted, various shapes can be appropriately employed. 15 and 16 illustrate a jig 110 as a different mode of the lens mounting table. The jig 110 has a structure in which a pair of plate-like members 116 and 116 that are opposed to each other in the radial direction of the cylindrical portion 114 are attached to the side surface of the cylindrical portion 114 provided with a through-hole 112 penetrating in the center. The height dimension of the plate-like member 116 is slightly larger than the axial dimension of the cylindrical portion 114, and the height positions of the lower edge portions thereof are aligned with each other, while the upper edge portion has a plate-like shape. The upper end edge of the member 116 protrudes slightly above the upper end edge of the cylindrical portion 114. Accordingly, the lens 12 placed on the cylindrical portion 114 is sandwiched between the plate-like members 116 and 116 so as not to fall down from the jig 110. In addition, the maximum width dimension of the jig 110 provided with the plate-like members 116 and 116 is substantially equal to the dimension of the opening of the cell 23, and the jig 110 is rotated in the cell 23 by the plate-like members 116 and 116. It is prevented from doing so and is positioned in the circumferential direction.

  Further, the outer shape measuring apparatus for measuring the outer shape of the ophthalmic lens is not limited to the structure as described above. FIG. 17 to FIG. 19 illustrate an external shape measuring apparatus 130 of different modes. In addition, since the external shape measuring apparatus 130 described below is configured using substantially the same members as the external shape measuring apparatus 10 described above, members and parts having the same structure as the external shape measuring apparatus 10 described above are used. Are denoted by the same reference numerals as those of the outer shape measuring apparatus 10, and detailed description thereof is omitted.

  The external shape measuring apparatus 130 is arranged such that the lens 12 is disposed at a fixed position with respect to the base plate material 132, and the dimension measuring device 16 is supported by a movable support base 134 that is also fixed to the base plate material 132. The position of the measuring device 16 can be adjusted with respect to the lens 12 in the Y-axis and Z-axis directions, and the measuring device 16 can be tilted about two axes in the X-axis direction and the Y-axis direction. The dimension measuring device 16 is moved horizontally in the X-axis direction to measure the outer dimension of the lens 12.

  The moving support table 134 that supports the dimension measuring device 16 is horizontally movable in the X-axis direction with the support device 14 in the external shape measuring device 10 described above attached to the X-axis stage 80 attached to the base plate 132. The structure is made. That is, the movable support base 134 is configured by stacking the X-axis stage 80, the tilt stage 18, the rotary stage 20, and the YZ-axis stage 22 in order from the bottom with respect to the base plate material 132. The dimension measuring device 16 is attached to the upper mounting plate portion 44 of the YZ axis stage 22 located at the uppermost stage of the movable support base 134. As a result, the position of the dimension measuring device 16 can be adjusted in the biaxial directions of the Y axis and the Z axis, and can be tilted about the two axes in the X axis direction and the Y axis direction. The dimension measuring device 16 can be moved horizontally in the X-axis direction by the X-axis stage 80 disposed at the lowermost stage of the movable support base 134.

  A gate-shaped frame member 136 is attached to the base plate member 132 so as to cover the movable support base 134 having such a structure from above. The frame member 136 is a member having a height dimension slightly larger than the height dimension of the movable support base 134, and has a top plate portion 138 extending in a substantially horizontal direction in the X-axis direction. The frame member 136 is attached to the base plate member 132 from above the moving support table 134, so that the top plate portion 138 of the moving support table 134 is interposed between the light projecting unit 96 and the light receiving unit 98 of the dimension measuring device 16. It arrange | positions so that it may extend in a X-axis direction.

  A cell attachment portion 56 for attaching the cell 23 is provided at the end of the top plate portion 138 on the light projecting portion 96 side. The cell attachment portion 56 is a member having a structure similar to that of the cell attachment portion 56 provided at the uppermost portion of the support device 14 in the above-described outer shape measuring apparatus 10.

  Accordingly, the light projecting unit 96 and the light receiving unit 98 of the dimension measuring device 16 are disposed with the lens 12 disposed above the top plate unit 138 interposed therebetween, and the light projecting unit 96 and the light receiving unit 98 are disposed. It is possible to measure the outer shape of the lens 12 by horizontally moving in the X-axis direction while maintaining the opposed arrangement state.

  In the outer shape measuring device 130 having such a structure, the dimension measuring device 16 is not disposed so as to straddle the upper portion of the cell 23 as in the above-described outer shape measuring device 10, but is disposed below the cell 23. Is done. Thereby, the upper space of the cell 23 is opened, and the installation and replacement of the cell 23 can be performed more easily. Further, since the frame member 136 that supports the lens 12 and the movable support base 134 that supports the dimension measuring device 16 are both fixed to the base plate member 132 and integrally formed, the mutual positioning is performed stably. And can be carried more easily.

  In the measurement method described above, the movement amount in the X-axis direction of the dimension measuring device 16 is set to be a constant movement amount with one step being 0.01 mm. The amount of movement of the dimension measuring device 16 in the X-axis direction may be varied at the edge portion. Specifically, for example, the shape of the optical part and the peripheral part is substantially constant and is represented by a relatively small curvature, whereas the edge part has a large curvature, so the optical part and the peripheral part are Then, the amount of movement of the dimension measuring device 16 in the X-axis direction may be set to 0.01 mm for one step, and one step may be set to 0.005 mm for the edge portion.

  In the above-described embodiment, the outer shape of the ophthalmic lens in a side view is measured. However, for example, the outer shape of the ophthalmic lens in a front view can be measured.

  Furthermore, in the above-described embodiment, when performing shape verification and evaluation from measurement data, the external shape of the ophthalmic lens obtained from the measurement data is displayed using a display screen, a projector (projector), a transparent sheet, or the like. The evaluation method using the measurement data is not limited as compared with the target design shape obtained from the design data by comparison (for example, see paragraph numbers [0086] and [0091]). For example, the outer shape of the ophthalmic lens obtained from the measurement data is expressed by an appropriate method using an interpolation method or a least square method between a plurality of points, and the obtained expression is compared with an expression representing the design shape. It is also possible.

  Furthermore, the difference between the lens outer shape based on such measurement data and the lens outer shape based on the design data is obtained, and the obtained difference data is fed back as a correction value for the mold shape to the ophthalmic lens mold design. It is also effective to reflect it. Specifically, for example, when designing a hydrous contact lens, when the radius of curvature on the convex surface side of the obtained lens is larger than the design shape by a value a in the hydrous state, this hydrous contact lens By correcting the curvature radius of the molding surface of the molding die so as to be reduced by an amount corresponding to a in consideration of the swelling ratio: α, it is possible to correct the shape of the obtained contact lens to be close to the design shape.

  In addition, although not enumerated one by one, the present invention can be carried out in a mode to which various changes, modifications, improvements, etc. are added based on the knowledge of those skilled in the art. It goes without saying that all are included in the scope of the present invention without departing from the spirit of the present invention.

It is a front view which shows the external shape measuring apparatus as one Embodiment of this invention. It is a side view of the support apparatus shown in FIG. FIG. 3 is a top view of the support device shown in FIG. 2. It is a longitudinal cross-sectional view of the mounting table of the ophthalmic lens with which the support apparatus shown in FIG. 2 is equipped, Comprising: It is a figure corresponded in the IV-IV cross section in FIG. It is a top view of the mounting base of the ophthalmic lens shown in FIG. It is a side view of the dimension measuring apparatus shown in FIG. It is a top view of the dimension measuring apparatus shown in FIG. It is explanatory drawing for demonstrating the external shape measuring method of the dimension measuring apparatus shown in FIG. It is a flowchart which shows the procedure of the external shape measuring method using the external shape measuring apparatus shown in FIG. It is explanatory drawing which shows the external view of the ophthalmic lens measured by the external shape measuring method of this invention, and the approximate circle obtained from this external shape. It is a flowchart which shows the procedure which compares the external shape obtained by the external shape measuring method of this invention with design design data. It is explanatory drawing which shows the comparison result by the procedure shown in FIG. It is a flowchart which shows the procedure which acquires an inner surface shape from the external shape obtained by the external shape measuring method of this invention, and thickness distribution. It is explanatory drawing for demonstrating the procedure of FIG. It is a top view which shows the further different aspect of the mounting base of the ophthalmic lens. It is a side view of the mounting base of the ophthalmic lens shown in FIG. It is a front view which shows the different aspect of the external shape measuring apparatus of this invention. It is a side view of the external shape measuring apparatus shown in FIG. It is a top view of the external shape measuring apparatus shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Outline measuring device 12 Contact lens 14 Support device 16 Dimension measuring device 18 Inclination stage 20 Rotating stage 22 YZ axis stage 23 Cell 62 Jig 76 Notch 80 X axis stage 96 Light projecting part 98 Light receiving part

Claims (12)

A method for measuring an outer shape of an ophthalmic lens,
By immersing the ophthalmic lens in water and irradiating the ophthalmic lens with a measurement light beam composed of parallel light, projection information of the ophthalmic lens is obtained, and an outer shape of the ophthalmic lens is based on the projection information. A method for measuring the outer shape of an ophthalmic lens, wherein   2. The projection information of the ophthalmic lens is obtained at a plurality of positions by using a slit-shaped luminous flux as the measurement luminous flux and moving the measurement luminous flux relative to the ophthalmic lens in the slit width direction. A method for measuring the outer shape of the ophthalmic lens according to claim 1.   As the measurement light beam, a slit-shaped light beam extending in parallel with the central axis of the ophthalmic lens is used, and the measurement light beam is irradiated from the side of the ophthalmic lens, and the measurement light beam is irradiated to the central axis of the ophthalmic lens. 3. The relative movement with respect to the ophthalmic lens in a direction perpendicular to the eye lens, and the position interval for obtaining the projection information is varied in a plurality of stages in the relative movement direction of the measurement light beam and the ophthalmic lens. Of measuring the outer shape of an ophthalmic lens.   The ophthalmic lens is a contact lens, and the contact lens with the convex surface facing upward is supported from below, so that the convex surface of the contact lens is exposed throughout the water, and the contact lens is disposed in the water. The method for measuring an outer shape of an ophthalmic lens according to claim 1, wherein the lens is irradiated with the measurement light beam.   The method for measuring an outer shape of an ophthalmic lens according to claim 1, wherein a measurement shape of the ophthalmic lens is obtained by specifying the outer shape of the ophthalmic lens with an approximate curve from the projection information.   6. The measurement shape of the ophthalmic lens is obtained by specifying the outer shape of the ophthalmic lens from the projection information, and the obtained measurement shape is compared with the design shape of the ophthalmic lens. The external shape measuring method of the ophthalmic lens of any one.   The external shape measuring method of the ophthalmic lens according to claim 1, wherein a laser beam is used as the measurement beam.   The ophthalmic lens is a contact lens, and the shape of the convex surface of the contact lens is specified from the projection information, and the thickness dimension of the contact lens is measured to determine the shape of the convex surface specified from the projection information The method for measuring an outer shape of an ophthalmic lens according to any one of claims 1 to 7, wherein the shape of the concave surface of the contact lens is measured based on the thickness dimension obtained by the measurement. An ophthalmic lens outer shape measuring apparatus for use in carrying out the ophthalmic lens outer shape measuring method according to any one of claims 1 to 8,
A storage case having a storage region for storing water and provided with support means for supporting the ophthalmic lens in water in the storage region is provided, and on one side opposed to the storage case, While the measurement light irradiation means for irradiating the measurement light beam is provided, the measurement light receiving means for receiving the measurement light beam is provided on the other side of the storage case, and the measurement in the storage case is performed. The side wall portion on the irradiation side of the light beam and the side wall portion on the light receiving side of the measurement light beam are both formed into a translucent flat plate shape extending perpendicular to the irradiation direction of the measurement light beam. Ocular lens external shape measuring device.   The external shape measurement of the ophthalmic lens according to claim 9, wherein the adjustment base base supporting the housing case is provided with a position adjustment mechanism for adjusting movement in three orthogonal axes and tilting around at least one axis. apparatus.   The measurement light irradiating means and the measurement light receiving means, which are arranged to face each other with the housing case in between, are integrated with each other while maintaining a fixed mutual facing state in a state where the housing case is fixed in position. The external shape measuring apparatus for an ophthalmic lens according to claim 9, further comprising an optical system moving means for horizontally moving the lens. The support means includes a support protrusion that protrudes upward from below in the storage area of the storage case, and the ophthalmic lens is placed on the protruding tip of the support protrusion. The width of the protruding tip portion on which the ophthalmic lens is placed is supported at least in the horizontal direction orthogonal to the irradiation direction of the measurement light beam. The outer periphery of the ophthalmic lens is smaller than the outer dimension of the lens, and the outer peripheral edge of the ophthalmic lens is located on both sides in the width direction of the protruding tip of the support protrusion. The external shape measuring apparatus for an ophthalmic lens according to any one of claims 9 to 11, wherein the external measuring apparatus is configured to protrude outward from the portion.

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