JP2005249487A - Surface shape measuring method and characteristics measuring method for spectacle lens - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a surface shape measuring method enabling to measure a surface shape of an object to be measured whose surface is a mirror surface, and a characteristics measuring method for a spectacle lens using the surface shape measuring method. <P>SOLUTION: After causing condensation on a surface of a spectacle lens, the surface shape of the spectacle lens is measured by a 3-dimensional measuring device. The 3-dimensional measuring device is to measure the surface shape of a spectacle lens based on a light-section method. A laser beam is irradiated to the spectacle lens on which condensation occurs (light emission process, processes S1-3). An imaging device takes an image of a diffuse reflection light of the spectacle lens and detects the light (detection process, processes S1-4). Based on the detected light, the surface shape of the spectacle lens is evaluated using a triangulation principle. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a surface shape measuring method and a spectacle lens characteristic measuring method.

Conventionally, as a method for simply measuring the surface shape of an object to be measured, a three-dimensional shape measuring method using the principle of triangulation has been used (for example, see Patent Document 1).
For example, by irradiating the object to be measured with slit-shaped laser light and observing the diffusely reflected light from a direction different from the irradiation direction of the slit light, based on the deformation of the slit light caused by the shape of the object to be measured, There is a light cutting method for measuring the shape.
In addition, the object to be measured is irradiated with striped light with different phases, and the change in phase due to the unevenness of the surface of the object to be measured is obtained using the light intensity information of the reflected light from the object to be measured. A pattern projection method for measuring is also known.

JP 2002-267430 A (refer to pages 2 to 4 and FIGS. 8 to 10)

In the three-dimensional shape measurement method using the principle of triangulation as described above, the surface of the object to be measured is irradiated with light, and the three-dimensional shape is measured using the light diffusely reflected from the surface of the object to be measured. Yes. When a measurement object having a mirror surface is measured by such a method, it is very difficult to capture the reflected light because the irradiated light is reflected only in a substantially normal direction with respect to the surface. Therefore, there is a problem that the three-dimensional shape of the measurement object whose surface is a mirror surface cannot be calculated.
In addition, in the case of a transparent object whose surface is a mirror surface and through which the irradiation light is transmitted, reflection may occur from the surface on the irradiation side and the surface from which light exits after transmission (back surface). There is a problem that measurement cannot be performed normally.

  An object of the present invention is to provide a surface shape measuring method capable of measuring the surface shape of an object to be measured having a mirror surface, and a spectacle lens characteristic measuring method using the surface shape measuring method.

  The surface shape measuring method of the present invention is a surface shape measuring method for measuring the surface shape of an object having a mirror-finished surface, a dew condensation step for condensing the surface of the object to be measured, and the surface of the object to be measured dewed The surface shape of the object to be measured is calculated based on the light irradiation step of irradiating light in the state, the detection step of detecting the reflected light diffusely reflected on the surface of the object to be measured, and the light detected in the detection step And a surface shape calculation step.

According to the present invention, since the surface of the object to be measured is condensed in the dew condensation process, the surface of the object to be measured becomes cloudy. When light is irradiated in the light irradiation process, the light is measured on the surface of the object to be measured. Will diffusely reflect. Therefore, the diffusely reflected light can be detected, and the surface shape of the object to be measured can be calculated based on the reflected light. Therefore, it is possible to accurately grasp the surface shape of the object to be measured whose surface is a mirror surface.
In addition, since the light is irradiated in a state where the surface of the object to be measured is condensed, the light is diffusely reflected on the surface of the object to be measured, so that the surface is a mirror surface and the irradiated light is transmitted. Even in the case of the object to be measured, there is no reflection from the surface on the irradiated side and the surface from which light exits after transmission (back surface) as in the past, and the surface shape of the object to be measured can be accurately grasped. Can do.

  In the present invention, the method for measuring the surface shape is not particularly limited as long as it is a measurement method using reflected light diffusely reflected on the surface of the object to be measured. For example, a so-called light cutting method may be used. Alternatively, a pattern projection method may be used. Furthermore, a method of calculating the surface shape of the object to be measured using the principle of triangulation by irradiating the surface of the object to be measured with spot-like light and detecting the reflected light of the spot-like light, etc. It may be.

At this time, in the light irradiation step, slit-shaped light is irradiated, in the detection step, reflected light is detected from a direction different from the irradiation direction of the slit-shaped light, and in the surface shape calculation step, the surface of the object to be measured It is preferable to calculate the surface shape of the object to be measured using the principle of triangulation based on the deformation of the reflected light according to.
According to the present invention, since the surface shape is calculated by a so-called light cutting method, a relatively wide range can be measured at high speed. For example, conventionally, an optical probe or the like is scanned with respect to the surface of the object to be measured, the coherent light from the light source is irradiated on the surface of the object to be measured and the reference surface, and the return light from the object to be measured and the reference surface There is a method of measuring the three-dimensional shape by interfering with the reflected light from the light source. However, in such a method, since the surface shape of the object to be measured is measured in a narrow range, it takes time for the measurement. On the other hand, in the present invention, since the surface shape is calculated by the light cutting method, the surface shape of the object to be measured can be measured in a relatively wide area, so that the measurement time can be greatly shortened.

Further, the present invention irradiates striped light having different phases in the light irradiation step, images reflected light in each phase of the object to be measured in the detection step, and images in the surface shape calculation step. Based on the reflected light, the surface shape of the object to be measured may be calculated using the principle of triangulation.
According to the present invention, since the surface shape is calculated by the so-called pattern projection method, a relatively wide range can be measured at high speed.

Furthermore, in the present invention, it is preferable that the object to be measured is a spectacle lens, and the light irradiated in the light irradiation step is ultraviolet light.
In general, a plastic spectacle lens absorbs light on a short wavelength side from around 400 nm. In the present invention, in the light irradiation step, the light irradiated to the object to be measured is changed to ultraviolet rays, so that the light does not pass through the spectacle lens, and the surface shape can be stably measured.

  The spectacle lens characteristic measuring method of the present invention includes a dew condensation process for condensing the spectacle lens surface, a light irradiation process for irradiating light with the spectacle lens surface condensed, and reflected light diffusely reflected on the spectacle lens surface. A detecting step for detecting, a surface shape calculating step for calculating a surface shape of the spectacle lens based on the light detected in the detecting step, a material refractive index of the spectacle lens is acquired, and preset measurement points A refractive characteristic calculating step of calculating a refractive characteristic of the spectacle lens from the surface shape of the spectacle lens and the material refractive index.

Here, the refractive characteristics of the spectacle lens indicate at least one of spherical refractive power, cylindrical refractive power, astigmatism axis, prism refractive power, and prism base direction.
According to the present invention, since the surface shape is calculated by the above-described surface shape measuring method, the surface shape can be accurately grasped. Since the refractive characteristics of the spectacle lens are calculated based on the accurately calculated surface shape, the refractive characteristics of the spectacle lens can be accurately grasped.

Conventionally, in order to grasp the refractive power distribution, there is a method (for example, Japanese Patent Application Laid-Open No. 08-247896) in which measurement is performed over the entire spectacle lens using a lens meter. Then, it is necessary to move the spectacle lens and the optical system on the lens meter side, and there is a problem that it takes time to grasp the refractive power distribution.
On the other hand, in the present invention, the surface shape is measured, and the refraction characteristics including the refractive power are calculated based on the surface shape. Therefore, any number of points can be calculated at a time. Accordingly, the refractive power distribution can be easily grasped.

  In the spectacle lens characteristic measuring method of the present invention, the spectacle lens is a progressive multifocal lens, and includes a spectacle lens positioning step for setting the spectacle lens at a reference position before the dew condensation step. preferable.

  According to the present invention as described above, after the spectacle lens is positioned, the surface shape is measured and the refraction characteristic is calculated, so that the refraction characteristic at a specific measurement point can be obtained. In the case of a progressive multifocal lens, it is necessary to determine the refractive characteristics of a preset measurement point, so it is useful to position the spectacle lens.

Furthermore, in the present invention, there is an outer shape calculation step for calculating the outer shape of the spectacle lens after the surface shape calculation step. In the outer shape calculation step, the surface shape calculated in the surface shape calculation step And a thickness dimension detecting step of detecting a thickness dimension of the spectacle lens by grasping a height position from a preset reference plane to the spectacle lens surface, and in the thickness dimension detecting step, It is preferable to include an outer shape acquisition step of recognizing a portion where the thickness dimension cannot be detected as an outer peripheral edge of the spectacle lens.
According to the present invention, since the thickness dimension and the outer shape of the spectacle lens can be calculated, whether or not the eyeglass lens is processed to an appropriate thickness, for example, in the front stage of the target lens processing, for example, the target lens shape It is possible to check whether or not
Conventionally, whether or not the target lens shape can be obtained has been determined by visually comparing the target lens shape printed on the paper and the spectacle lens. In the present invention, the outer shape is calculated. Therefore, the determination accuracy can be improved.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows a method for measuring characteristics of a spectacle lens L (see FIG. 2) according to this embodiment.
Here, the spectacle lens L is a plastic transparent spectacle lens, and is an inner surface progressive multifocal lens whose surfaces (object side surface and eyeball side surface) are mirror surfaces.
The spectacle lens L characteristic measuring method includes a surface shape measuring step (processing S1) for measuring the surface shape of the spectacle lens L (the shapes of both the object-side surface and the eyeball-side surface), and refractive characteristics. It has a calculation process (process S2) and an outer shape calculation process (process S3).

[1. Surface shape measurement process]
First, the surface shape measurement step (processing S1) will be described. This surface shape measurement process (process S1) includes a spectacle lens L positioning process (process S1-1), a dew condensation process (process S1-2) for condensing the surface of the spectacle lens L, and a light irradiation process (process S1-3). ), A detection step (processing S1-4), and a surface shape calculation step (processing S1-5).
First, a positioning process for installing the spectacle lens L at a reference position on the installation table 5 (see FIG. 3) is performed (processing S1-1). In the latter-stage refractive characteristic calculation step (process S2), since it is necessary to calculate the refractive characteristics at preset measurement points (L3 and L4 in FIG. 2), the position of the spectacle lens L is measured before the surface shape is measured. It is necessary to carry out.
As shown in FIG. 2, a pair of hidden marks L1 is formed on the spectacle lens L. The hidden mark L1 is obtained by transferring a mark attached to the mold of the spectacle lens L. The pair of hidden marks L1 are formed at equal distances, for example, 17 mm, with the optical reference position L2 of the spectacle lens L interposed therebetween. Based on this hidden mark L1, the spectacle lens L is positioned.
The measurement point L3 is a measurement point in the distance portion of the spectacle lens L, and the measurement point L4 is a measurement point in the near portion of the spectacle lens L.

In the positioning process, the alignment device 3 shown in FIG. 3 is used. The alignment device 3 includes an irradiation unit 31 and a projection image display unit 32 that are arranged to face each other with the spectacle lens L interposed therebetween. A projection position display unit 33 is installed between the irradiation unit 31 and the spectacle lens L.
The irradiation unit 31 irradiates illumination light toward the spectacle lens L.
The projection type position display unit 33 is provided with a pair of alignment marks 331.
The projection image display unit 32 displays the image of the hidden mark L1 of the spectacle lens L irradiated by the irradiation unit 31 and the image of the alignment mark 331 of the projection position display unit 33. It is a transparent screen, and its projected image can be taken by the camera 34 and observed on a monitor or the like.

In such an alignment apparatus 3, the illumination light is emitted toward the spectacle lens L, the hidden mark L 1 of the spectacle lens L and the alignment mark 331 of the projection position display unit 33 are projected onto the projection image display unit 32, While taking the projected image with the camera 34 and observing it with a monitor (not shown) or the like, the spectacle lens L is rotated and moved so that the hidden mark L1 and the alignment mark 331 are in a predetermined positional relationship. Do it.
Using such an alignment device 3, the spectacle lens L is installed at a reference position on the installation table 5.

Next, a dew condensation process (process S1-2) is performed to dew the surface of the spectacle lens L installed at the reference position on the installation table 5.
FIG. 4 shows the dew condensation apparatus 1 for performing the dew condensation process (Process S1-2).
The dew condensation device 1 is a device that causes dew condensation on the surface of the spectacle lens L whose three-dimensional shape is measured by the three-dimensional measurement device 2 (see FIG. 5). The dew condensation device 1 includes a hollow main body 12 in which a Peltier element 11 is installed, pipes 13 and 14 connected to the main body 12, and fans 15 and 16 for circulating air inside the main body 12. Have

A partition wall 121 that divides the interior of the main body portion 12 into two parts is installed inside the main body portion 12, and the Peltier element 11 is fitted into the partition wall 121. Although not specifically shown, the Peltier element 11 has a plurality of junction pairs formed by joining a p-type semiconductor and an n-type semiconductor with metal pieces (electrodes). Are connected in series, and a direct current flows from the n-type semiconductor to the p-type semiconductor or from the p-type semiconductor to the n-type semiconductor.
Here, when a direct current is passed from the n-type semiconductor to the p-type semiconductor, one surface of the Peltier element 11 becomes a heat absorbing portion that absorbs heat, and the other surface becomes a heat generating portion that generates heat.
Therefore, in the space divided by the partition wall 121 of the main body 12, the side where one surface of the Peltier element 11 is exposed becomes the cooling chamber 122, and the part where the other surface of the Peltier element 11 is exposed becomes the heating chamber 123.

The piping 13 described above is connected to the cooling chamber 122, and the cooled air is discharged from the piping 13. By installing the spectacle lens L at the discharge port portion of the pipe 13, the spectacle lens L is cooled.
The heating chamber 123 is connected to a nozzle 17 for spraying a liquid, for example, water. When water is sprayed from the nozzle 17 into the heated greenhouse 123, the water exists as a gas due to the temperature in the heated greenhouse 123. Therefore, the inside of the heated greenhouse 123 is in a hot and humid state.
Moreover, the piping 14 is connected to the heating chamber 123, and the air inside the heating chamber 123 is discharged from the piping 14. A spectacle lens L can be installed at the outlet of the pipe 14.

The dew condensation process (Process S1-2) is performed as follows using the dew condensation apparatus 1 as described above.
The Peltier element 11 is driven in advance to cool the cooling chamber 122 of the dew condensation device 1 and warm the warming chamber 123. Further, water is sprayed from the nozzle 17 into the heating chamber 123.
Next, the installation base 5 is installed so that the surface of the spectacle lens L and the discharge port of the pipe 13 face each other. Then, the cooled air in the cooling chamber 122 is discharged from the pipe 13 to cool the spectacle lens L.
Next, when the spectacle lens L is sufficiently cooled, the installation base 5 is moved and installed so that the discharge port of the pipe 14 faces the surface of the spectacle lens L.
Then, hot and humid air in the heated greenhouse 123 is discharged from the pipe 14. As a result, the surface of the spectacle lens L is condensed. Note that the size of water droplets attached to the surface of the spectacle lens L due to condensation is, for example, about 10 μm.

When the dew condensation process (process S1-2) is completed as described above, the light irradiation process (process S1-3), the detection process (process S1-4), and the surface shape calculation process (process S1-5) are performed.
With reference to FIG. 5, the three-dimensional measuring apparatus 2 for implementing a light irradiation process (process S1-3), a detection process (process S1-4), and a surface shape calculation process (process S1-5) is demonstrated.
This three-dimensional measuring apparatus 2 is for measuring the surface shape of a spectacle lens L as an object to be measured based on a light cutting method. The three-dimensional measuring apparatus 2 includes a laser light transmitting device 22 that irradiates the spectacle lens L with laser light, an imaging unit 23 that images diffused reflected light from the spectacle lens L, and a control device 24.

Although not shown, the laser light transmission device 22 generates continuous wave laser light, and includes a laser light source that emits ultraviolet light as laser light, a first cylindrical lens, and a second cylindrical lens. In such a laser beam transmission device 22, the light emitted from the laser light source is diffused through the first cylindrical lens and then passed through the second cylindrical lens, so that the slit-shaped (linear) laser beam is generated. It will be injected.
The laser beam transmitter 22 is rotatable in the direction of arrow R so that the laser beam can be irradiated over the entire surface of the spectacle lens L. The control of the laser beam irradiation direction is not limited to this method, and the angle may be controlled by, for example, a galvanometer mirror.

The imaging unit 23 includes an imaging lens 231 and an imaging unit main body 232 (see FIG. 6). The imaging means main body 232 is, for example, a CCD camera equipped with a CCD (Charge Coupled Device) as a light receiving element. In the present embodiment, the imaging means body 232 is a CCD camera. However, the present invention is not limited to this. For example, a CMOS (Complementary Metal Oxide Semiconductor) sensor may be provided as a light receiving element.
The control device 24 stores a calculation result, and a control unit 240 having a driving unit 241 that drives the laser beam transmitter 22, a calculation unit 242 that calculates the surface shape of the spectacle lens L from the reflected light imaged by the imaging unit 23, and the calculation result. And a storage unit 243.

The computing unit 242 calculates the surface shape of the spectacle lens L as follows based on the light cutting method. This will be described with reference to FIG.
In the light cutting method, the reflected light obtained by diffuse reflection from the spectacle lens L is guided to the imaging means main body 232 by the imaging lens 231 and based on the deformation of the reflected light according to the surface of the spectacle lens L (that is, the spectacle lens L This is a method of detecting the condensing position of the reflected light on the imaging means main body 232 that changes according to the unevenness of the surface and measuring the three-dimensional shape of the surface of the spectacle lens L based on this.
Here, the length dimension of the base line T connecting the laser beam transmitter 22 and the imaging means 23 is T1. Laser light is emitted from the laser light transmission device 22 at an angle θ, and this laser light is reflected by the surface of the spectacle lens L at the position A and is incident at a position at which the imaging lens 231 of the imaging means 23 is at an angle φ. To form an image.
At this time, the following relational expression is established. Za is the distance from the laser beam transmitter 22 to the point A.

  Next, when the laser beam is reflected at point B on the surface of the spectacle lens L, assuming that the imaging position on the imaging means main body 232 is shifted by X from the point A, the angle ω is Equation (2) is obtained. Y is the distance between the imaging lens 231 and the imaging means body 232.

  The distance Zb from the laser beam transmitter 22 to the point B is expressed by the following equation.

  When the laser beam from the laser beam transmitter 22 is scanned at the irradiation angle θ so as to irradiate the entire surface of the spectacle lens L, and the above calculation is repeated for each irradiation angle θ, each reflection point of the spectacle lens L and the base line T Distance Z, that is, the surface shape of the spectacle lens L is calculated.

The surface shape of the spectacle lens L is measured by the three-dimensional measuring apparatus 2 as described above as follows.
First, a laser beam is irradiated from the laser beam transmission device 22 to the spectacle lens L whose surface has been condensed (light irradiation step, process S1-3).
Next, the imaging unit 23 captures and detects diffuse reflection light from the spectacle lens L (detection process S1-4). Then, the surface shape of the spectacle lens L is calculated by the calculation unit 242 of the control device 24 based on the detected light by the method described above (surface shape calculation step, process S1-5). Then, the calculation result is stored in the storage unit 243 of the control device 24. In this way, the shape of the surface of the spectacle lens L can be measured.
In the present embodiment, since the refraction characteristics and the like of the spectacle lens L are calculated after the surface shape measurement step, the above-described processes S1-1 to S1˜ are performed not only on one surface of the spectacle lens L but also on the other surface. S1-5 is performed to grasp the other surface shape.
In the process up to and including the subsequent steps, condensation on the surface of the spectacle lens L is eliminated. Condensation can be eliminated naturally over time, but it can be eliminated in a short time by combining, for example, blowing hot air or dehumidifying.

[2. Refractive property calculation process]
As described above, after grasping the surface shape of the spectacle lens L, the refractive characteristics are calculated (refractive characteristic calculating step, process S2). The calculation of the refraction characteristics may be performed by giving the control device 24 of the above three-dimensional measuring device 2 a function of calculation, or may be performed using a personal computer or the like other than the control device 24.
Here, the refraction characteristics refer to spherical refractive power, cylindrical refractive power, astigmatism axis, prism refractive power, and prism base direction in this embodiment. The spherical refractive power, cylindrical refractive power, and prism refractive power are calculated at preset measurement points (for example, measurement points L3 and L4).
[2-1. Calculation of curvature]
First, the curvature of the eyeball side surface of the spectacle lens L is calculated (curvature calculation step, process S2-1). As shown in FIG. 7, each curvature of 180 ° is obtained for every 1 ° around the reference line L5 passing through the optical reference position L2 on the eyeball side surface of the spectacle lens L. Since the curvature is necessary when calculating the refractive power of the measurement points set in advance (for example, measurement points L3 and L4), it is preferable to know the curvature in the vicinity of the measurement points. As shown in FIG. 5, for example, the curvature is calculated from three points centered on L3 which is a preset measurement point.
Next, also on the object side surface of the spectacle lens L, each curvature for 180 ° is obtained for every 1 ° around the reference line L5 passing through the optical center position. At this time, it is preferable to extend the normal line from the measurement point L3 to the object side surface and grasp the curvature in the vicinity of the point L6, which is an intersecting point, and calculate the curvature from the three points centered on the point L6. .

[2-2. Calculation of refractive power
Next, the refractive power of the material of the spectacle lens L is acquired in advance (material refractive power acquisition step, process S2-2).
Next, the refractive power is calculated (refractive power calculation step, process S2-3). The thickness d of the spectacle lens L (for example, when calculating the refractive power at the measurement point L3, the thickness of the center between the measurement point L3 and the point L6 (see FIG. 8)) is calculated. A predetermined reference plane is set in advance, and up to two spectacle lens L surfaces (for example, measurement point L3 and point L6) based on the surface shape measured in the surface shape measurement step (process S1) from the reference plane. Find the distance. And let this be thickness d.
Next, the principal point refractive power is calculated based on the following equation. Here, D is the principal point refractive power of the spectacle lens L, D1 is the refractive power of the object-side surface, D2 is the refractive power of the eyeball-side surface, and r1 is the radius of curvature (mm) of the object-side surface. , R2 is the radius of curvature (mm) of the eyeball side surface, and n is the refractive index of the material of the spectacle lens L.

Next, here, the calculated principal point refractive power D is converted into vertex refractive power D ′.
First, as shown in FIG. 9, the focal length f on the eyeball side surface is calculated.

次に、眼球側の面の頂点から主点までの距離ｈを算出する。

Next, a distance h from the vertex of the eyeball side surface to the principal point is calculated.

  Then, the back focus Bf of the eyeball side surface is calculated.

As described above, the reciprocal of the calculated back focus Bf becomes the vertex refractive power D ′ on each surface side.
Such vertex power D ′ is calculated for each curvature calculated every 1 ° in the curvature calculation step.
Then, the vertex refractive power D ′ closest to 0.00D becomes the spherical refractive power, and the vertex refractive power D ′ far from 0.00D becomes the total refractive power. The cylindrical refractive power is calculated by subtracting the spherical refractive power from the total refractive power.

[2-3. Calculation of prism refractive power and base direction]
Further, the prism refractive power and the base direction of the spectacle lens L are calculated (prism refractive power and base direction calculating step, process S2-4).
First, based on the surface shape of the spectacle lens L acquired in the surface shape measurement step, for example, assuming a circle with a radius of 2.5 mm around the measurement point (for example, the measurement point L3), The inclinations of the eyeball side surface (substantially flat surface) and the object side surface (substantially flat surface) are calculated.
The base direction is obtained from the inclination of both sides. Further, the angle formed by both surfaces (corresponding to the apex angle α of the prism) is obtained, and the deviation angle γ is calculated from the apex angle α and the material refractive index n based on the following formula (10).

  The unit of the prism refractive power is a prism diopter (Δ), and 1Δ is defined as a refractive power that gives a deflection of 1 cm at 1 m. Therefore, the argument γ can be defined as the following equation (11). Here, P represents the amount of displacement between the light incident on the measurement point of the spectacle lens L and the emitted light, and corresponds to the prism refractive power P.

  Therefore, the prism refractive power P is obtained as in the following formula (12).

[3. Outline shape calculation process]
Next, the outer shape of the spectacle lens L is calculated (outer shape calculation step, process S3).
A predetermined reference plane is set in advance, and the distance from the reference plane to the two surfaces of the spectacle lens L is determined based on the calculated surface shape measurement (thickness dimension detection step).
The outer shape is calculated by connecting portions where the thickness dimension is not detected (outer shape acquisition step).

  By comparing the refractive characteristics of the spectacle lens L calculated as described above with the designed refractive characteristics, it can be confirmed that the lens has a desired characteristic within a predetermined range. Further, by comparing the calculated outer shape with the target lens shape, it is possible to determine whether or not a desired target lens shape can be obtained when putting a frame (when putting the spectacle lens L into the spectacle frame). it can.

Therefore, according to this embodiment, the following effects can be produced.
(1) Since the surface of the spectacle lens L is condensed in the surface shape measurement step for measuring the surface shape of the spectacle lens L, the surface of the spectacle lens L becomes cloudy, and light is irradiated in the light irradiation step. Thus, the light is diffusely reflected on the surface of the spectacle lens L. Therefore, unlike the conventional case, reflection does not occur from the irradiated side surface and the surface (back surface) from which light is extracted after transmission.
Then, by detecting the diffuse reflection light diffusely reflected on the surface of the spectacle lens L, the surface shape of the spectacle lens L can be accurately calculated based on the reflected light. Therefore, the surface is a mirror surface, and the surface shape of the transparent spectacle lens L can be accurately grasped.

(2) In this embodiment, since the surface shape is calculated by a so-called light cutting method, a relatively wide range can be measured at high speed. For example, an optical probe or the like is scanned with respect to the spectacle lens surface, the coherent light from the light source is irradiated on the spectacle lens and the reference surface, and the return light from the spectacle lens and the reflected light from the reference surface are There is a method of measuring the three-dimensional shape by causing interference, but in such a method, since the surface shape of the spectacle lens is measured in a narrow range, it takes time for the measurement. On the other hand, in this embodiment, the surface shape is calculated by the light cutting method, and the surface shape of the spectacle lens can be measured in a relatively wide area, so that the measurement time can be greatly shortened. .

(3) The spectacle lens L absorbs light on the short wavelength side from around 400 nm. In the present embodiment, since the laser light emitted from the laser light transmission device 22 is ultraviolet light, the light does not pass through the spectacle lens L, and the surface shape can be stably measured.
(4) In the present embodiment, the surface shape of the spectacle lens L is accurately grasped, and the refraction characteristics of the spectacle lens are calculated based on the grasped surface shape. The characteristics can be grasped.

(5) Conventionally, as a method for measuring the refractive power distribution, there is a method in which a lens meter is used and measurement is performed over the entire surface of the spectacle lens. There is a problem that it is necessary to move the optical system, and it takes time to grasp the refractive power distribution.
On the other hand, in the present embodiment, the surface shape is measured, and the refractive power is calculated based on the surface shape. Therefore, any number of points can be calculated at once. Accordingly, the refractive power distribution can be easily grasped.
(6) In this embodiment, after the spectacle lens L is positioned, the surface shape is measured and the refraction characteristics are calculated, so that the refraction characteristics at a specific measurement point set in advance are obtained. It becomes possible.

(7) Further, in the outer shape calculation step, by calculating the outer shape of the spectacle lens L, it is possible to confirm, for example, whether or not the target lens shape can be obtained in the previous stage of the target lens shape processing.
Conventionally, whether or not the target lens shape can be obtained has been determined by visually comparing the target lens shape printed on the paper and the spectacle lens. In this embodiment, the outer shape is calculated. Therefore, the determination accuracy can be improved.
Furthermore, since the thickness dimension of the spectacle lens L is acquired in the outer shape calculation step, it can be determined whether or not the eyeglass lens L has been processed to an appropriate thickness.
(8) Conventionally, when the refraction characteristics and the outer shape of the spectacle lens L are inspected, the refraction characteristics of the spectacle lens L are measured by a lens meter, and it is determined whether or not a predetermined value is exhibited. Inspection was performed, and the outer shape was inspected by comparing the lens shape printed on the paper surface with a spectacle lens.
On the other hand, in the present embodiment, since the outer shape and the refraction characteristics can be calculated from the measured surface shape of the spectacle lens L, the refraction characteristics and the outer shape can be inspected in one step. Yes, work in inspection can be simplified.

It should be noted that the present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the present invention.
For example, in the above-described embodiment, the surface shape of the spectacle lens L is measured by a so-called light cutting method in the surface shape measuring step, but the measurement is not limited to this, and the surface shape may be measured by a so-called pattern projection method.
For example, a three-dimensional measuring device 4 as shown in FIG. 10 is used. The three-dimensional measuring device 4 includes a projector 41, an imaging unit 42, and a control device 43. The projector 41 includes a light source 411, a phase grating 412, and a grating driving device 413. The light source 411 is, for example, a halogen lamp or an LED (light emitting diode). Visible light may be emitted from the light source 411, and ultraviolet light may be emitted.
The phase grating 412 is composed of stripes having a sinusoidal light amount distribution, and is a film on which a sinusoidal shading pattern is drawn.
The grating driving device 413 drives the phase grating and can shift the light pattern projected onto the spectacle lens L.
The imaging means 42 is a CCD camera provided as a light receiving element including a CCD (Charge Coupled Device).

In such a three-dimensional measuring apparatus 4, the phase is shifted by 90 degrees, and the reflected light is imaged from the spectacle lens L in each phase. Then, the four images obtained by performing the photographing four times are analyzed, the relationship between each pixel of the image and the position and phase of the fringe is determined, and each surface on the surface of the spectacle lens L is obtained using the principle of triangulation. The distance to the point is obtained, and thereby the surface shape of the spectacle lens L is grasped.
Even when the surface shape of the spectacle lens L is measured using such a three-dimensional measuring device 4, the same effects as in the above embodiment can be obtained.

Furthermore, instead of the pattern projection method using the phase grating as described above, other pattern projection methods for obtaining three-dimensional information by projecting density gradient light whose light intensity changes at a constant rate are obtained. The surface shape of the spectacle lens L may be measured.
Moreover, in the said embodiment, after measuring the surface shape of the spectacle lens L in the surface shape measurement step, the refraction characteristics and the like were calculated based on the measurement result. Based on this, for example, laser processing may be performed. When performing laser processing, it is necessary to move the focal position of the laser light in accordance with the inclination of the surface of the spectacle lens L. In the surface shape measurement step of the spectacle lens L, an accurate surface shape can be grasped. Therefore, laser processing can be performed accurately by performing laser processing based on this result.

Furthermore, in the above embodiment, the spectacle lens L is an inner surface progressive multifocal lens, but it may be an outer surface progressive multifocal lens or a single focal lens.
In addition, the dew condensation device used in the surface shape measurement process of the embodiment is not limited to the dew condensation device 1 described above, and any structure can be used as long as it can generate dew condensation on the surface of the object to be measured. For example, a structure having a cooler and a humidifier that evaporates water using a heater or the like may be used. In this case, after the object to be measured is cooled by the cooler, the surface of the object to be measured is condensed by the air discharged from the humidifier.
In the above embodiment, the surface shape of the spectacle lens L is measured in the surface shape measurement step. However, the present invention is not limited to this, and any method may be used as long as the surface has a specular surface. Other optical components may be used. Further, it may be a mold for manufacturing an optical component.

  The present invention can be used for measurement of the surface shape of an object to be measured having a mirror surface, for example, measurement of the surface shape of a spectacle lens.

The flowchart which shows the characteristic measuring method of the spectacle lens concerning embodiment of this invention. The top view which shows the spectacles lens concerning embodiment of this invention. The schematic diagram which shows the position alignment apparatus in the said embodiment. The schematic diagram which shows the dew condensation apparatus in the said embodiment. The schematic diagram which shows the three-dimensional measuring apparatus in the said embodiment. The schematic diagram which shows the principle of the light cutting method. The figure explaining the curvature calculation process of a spectacle lens. The figure explaining the curvature calculation process of a spectacle lens. The figure explaining the refractive power calculation process of a spectacle lens The schematic diagram which shows the modification of a three-dimensional measuring apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Condensing apparatus, 2 ... Three-dimensional measuring apparatus, 3 ... Positioning apparatus, 4 ... Three-dimensional measuring apparatus, 5 ... Installation stand, 11 ... Peltier element, 12 ... Main-body part, 13 ... Piping, 14 ... Piping, 15, DESCRIPTION OF SYMBOLS 16 ... Fan, 17 ... Nozzle, 22 ... Laser beam transmitter, 23 ... Imaging means, 24 ... Control apparatus, 31 ... Irradiation part, 32 ... Projection image display part, 33 ... Projection type position display part, 34 ... Camera, 41 ... projector, 42 ... imaging means, 43 ... control device, 121 ... wall, 122 ... cooling room, 123 ... heating chamber, 231 ... imaging lens, 232 ... imaging means body, 240 ... control section, 241 ... drive section, 242 ... Calculation unit, 243 ... Storage unit, 331 ... Mark, 411 ... Light source, 412 ... Phase grating, 413 ... Grating driving device, L ... Spectacle lens, L2 ... Optical reference position, L3, L4 ... Measurement point, L5 ... Reference Line, L6 ... dot

Claims (7)

A surface shape measuring method for measuring the surface shape of an object whose surface is a mirror surface,
A condensation process for condensation on the surface of the object to be measured;
A light irradiation step of irradiating light with the surface of the object to be measured condensed,
A detection step of detecting reflected light diffusely reflected on the surface of the object to be measured;
And a surface shape calculating step of calculating a surface shape of the object to be measured based on the light detected in the detecting step. In the surface shape measuring method according to claim 1,
In the light irradiation step, the slit-shaped light is irradiated,
In the detection step, the reflected light is detected from a direction different from the irradiation direction of the slit-shaped light,
In the surface shape calculating step, the surface shape of the object to be measured is calculated using the principle of triangulation based on the deformation of the reflected light according to the surface of the object to be measured. In the surface shape measuring method according to claim 1,
In the light irradiating step, radiate stripe light having different phases,
In the detection step, the reflected light in each phase of the object to be measured is imaged,
In the surface shape calculating step, the surface shape measuring method is characterized in that the surface shape of the object to be measured is calculated using the principle of triangulation based on the captured reflected light. In the surface shape measuring method in any one of Claim 1 to 3,
The object to be measured is a spectacle lens,
The surface shape measuring method, wherein the light irradiated in the light irradiation step is ultraviolet light. A condensation process that condenses the spectacle lens surface;
A light irradiation step of irradiating light in a state where the surface of the spectacle lens is condensed;
A detection step of detecting reflected light diffusely reflected on the spectacle lens surface;
A surface shape calculation step of calculating a surface shape of the spectacle lens based on the light detected in the detection step;
A refractive index calculating step of acquiring a material refractive index of the spectacle lens and calculating a refractive characteristic of the spectacle lens from a surface shape of the spectacle lens at a preset measurement point and the refractive index of the material. A method for measuring characteristics of spectacle lenses. In the characteristic measurement method of the spectacle lens according to claim 5,
The spectacle lens is a progressive multifocal lens;
A spectacle lens characteristic measuring method comprising a spectacle lens positioning step for installing the spectacle lens at a reference position before the dew condensation step. In the characteristic measurement method of the spectacle lens according to claim 5 or 6,
An outer shape calculation step of calculating an outer shape of the spectacle lens at a later stage of the surface shape calculation step;
In the outer shape calculation step, based on the surface shape calculated in the surface shape calculation step, the height position from the preset reference plane to the spectacle lens surface is grasped, and the thickness dimension of the spectacle lens is detected. A thickness dimension detection process to be performed;
A method for measuring spectacle lens characteristics, comprising: an outer shape obtaining step of recognizing a portion where the thickness dimension of the spectacle lens cannot be detected as an outer peripheral edge of the spectacle lens in the thickness dimension detecting step.

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