The present invention relates to a lens shape measurement device which measures a lens shape of eyeglasses.
In general, as eyeglass frames, a rim frame (full rim), a two-point frame (rimless frame), a grooved frame (half-rim and Nylor) and the like are known.
As a two-point frame in theses eyeglass frames, a two-point frame disclosed in JP 2005-275190A is known. As this two-point frame, two-point frame eyeglasses 100 illustrated in
In order to fasten the attachment 106 to the right side eyeglass lens MR by the fastening screw 108 as illustrated in
The attachment 106 for fitting a temple includes a side plate portion 106a which has contact with an ear side portion of the circumferential face of the eyeglass lens MR and a fastening plate portion 106b which has contact with an ear side portion of a rim portion of a front side refracting face fr of the eyeglass lens MR. An angle between the side plate portion 106a and the fastening plate portion 106b of the attachment 106 is set to α.
Meanwhile, when manufacturing the above-described two-point frame eyeglasses 100, it is general for a person wearing eyeglasses to measure refracting power and check a visual performance of eyes and also to select an eyeglass frame in an eyeglass shop. In an eyeglass shop, it is general to display eyeglasses in which a lens such as a demo-lens (dummy lens) is fitted in a frame.
Even in two-point frame eyeglasses, the above attachment 101, 105, 106 and the like are fitted in a demo-lens (dummy lens). Moreover, the position of the mounting hole 109 into which the attachment 106 is fitted is the same as the position in actual eyeglasses. For this reason, it is necessary to measure the position of the attachment hole 109 into which the attachment 106 is fitted. This is the same as the bridge 101, the attachment 105 and the like.
As a method of measuring a position of such a mounting hole 109, a method of obtaining a shape of a lens and a mounting hole from output of a light receiving element by projecting parallel illumination light flux from one face of a lens and receiving the light flux which has transmitted the lens and the light flux around that by the light receiving element as described in Spanish Patent Application No. 2006-00589.
However, the mounting hole is formed to be inclined to a lens. For this reason, the projection positions to the light-receiving element of the opening of both ends of the mounting hole are overlapped out of alignment, and the inside opening of the mounting hole and the opening on the side into which the illumination light enters are reflected by the lens to be projected on the light-receiving element; thus, the position of the mounting hole can not be accurately measured.
It is, therefore, an object of the present invention to provide a lens shape measuring device which can easily and accurately measure a position of a mounting hole for fitting an attachment of a two-point frame into a lens.
In order to achieve the above object, a lens shape measurement device according to the embodiment of the present invention includes a lens holder set in a measuring element main body, a measuring element for a lens configured to measure a rim shape of a lens, the measuring element for a lens having a leading end portion engageable with a mounting hole of the lens for an attachment, which is held in the lens holder, and a side face which has contact with a circumferential face of the lens to be moved therealong, a measurement element shifter configured to displace the measuring element for a lens along an outer circumferential face of the lens, a first position detector configured to detect a position of the measuring element for a lens along the outer circumferential face, a second position detector configured to detect a position in the direction orthogonal to the first position detector, and an arithmetic control circuit configured to obtain a relationship between the rim shape and a position of the mounting hole based on a detection signal from the second position detector by controlling the measuring element shifter to move the leading end of the measuring element for a lens to have contact with an refracting face of the lens held in the lens holder.
According to the present invention, a position of a mounting hole of a lens into which an attachment of a two-point frame can be easily and accurately measured.
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
A lens shape measurement device according to the present invention is used for measuring a shape of a lens such as a template, a demo-lens or a lens frame. In this case, a distance (diameter) from a geometric center of a lens to a circumferential face of a lens is changed in a plurality of positions in the circumferential direction of the lens, so that a diameter in which this distance is changed can be a moving radius.
This measurement device main body 1 includes in a lower portion thereof a case portion 1a for housing the measurement mechanism and a lens frame holding mechanism 1b provided above the case portion 1a. The case portion 1a in
The lens frame retaining mechanism 1b includes a pair of parallel guide rods (guide members) 1c, 1c fastened to the case portion. Slide frames 3, 3 are retained by the guide members 1c, 1c, which can relatively move closer and move away. These slide frames 3, 3 are biased by a coil spring and the like in the direction where they come close to each other. These slide frames 3, 3 include facing longitudinal walls 3a, 3a with which a lens frame (not shown) of eyeglasses has contact. The slide frames 3, 3 include a lens frame holder 3b which holds a lens frame as a lens frame holding unit. This lens frame holder 3b includes a lower side holding bar 3b1 which projects from the longitudinal wall 3a and an upper side holding bar 3b2 which is attached to the slide frame 3 in an openable and closable manner with respect to the holding bar 3b1 from the upper side. The lens frame holder 3b is attached to each of right and left lens frames of not shown eyeglasses. In addition, as the lens frame holding mechanism 1b, a configuration disclosed in JP H10-328992A, for example, or other known arts can be adopted. Thus, the detailed description of the lens frame holding mechanism 1b is omitted.
A measurement mechanism 1d illustrated in
Upon the driving of the driving motor 6, the rotation of the output shaft 6a of the driving motor 6 is transferred to the driven gear 5 via the pinion 7 and the timing belt 8, and the driven gear 5 rotates. In addition, the driving motor 6 is a biphasic stepping motor.
As illustrated in
Facing parallel rail attachment plates 10, 11 each of which extends upwardly illustrated in
As illustrated in
Moreover, as illustrated in
A driven pulley 17 is attached to the pulley supporting plate portion 12a to be horizontally rotatable about an axis line extending up and down. An upper end portion of a driving motor 18 for moving a slider is fastened to the bracket 16. A DC motor is used for this driving motor 18. The axis line of the output shaft 18a of the driving motor 18 is vertically directed, and a driving pulley 19 is attached to the output shaft 18a as illustrated in
A circular wire 20 is stretched over the pulleys 17, 19. A portion adjacent to one end portion of the wire 20 is held by a shaft-like wire holding member 21. This wire holding member 21 is fastened to the slider 15 via bracket 22, 22′. Both of the end portions of the wire 20 are connected via a coil spring 23. Thereby, upon the normal rotation or the reverse rotation of the driving motor 18, the output shaft 18a and the driving pulley 19 normally rotate or reversely rotate, so that the slider 15 is displaced right or left in
As illustrated in
As the origin sensor 20a, a known technique such as a transparent photosensor and a proximity photosensor can be adapted.
A supporting plate portion 13a which horizontally projects to the side as illustrated in
This linear scale 24 includes a shaft-like main scale 25 held by the slider 15 parallel to the guide rail 14 and a detection head 26 which is fastened to the supporting plate portion 13a and reads the positional information of the main scale 25. This detection head 26 detects the displaced position of the slider 15 in the horizontal direction from the information for detecting the position of the main scale 25. For example, a known magnetic scale or optical scale can be used for this linear scale 24.
For instance, in a magnetic scale, a magnetic pattern S, N is alternately provided at minute intervals as information for detecting a position (information for detecting displacement) in the axis line direction of the main scale 25, and the magnetic pattern is detected by a detection head (a head for detecting a magnetic change) 26, so that the displacement (displaced position) of the slider 15 can be detected. Meanwhile, in an optical scale, the main scale 25 is formed in a plate-like form and fine interval slits are provided in the longitudinal direction of the main scale 25, and a light emitting element and a light receiving element are placed to sandwich the main scale 25 and the light from the light emitting element is detected by the light receiving element via the slits of the main scale 25, so that the displacement (displaced position) of the slider 15 can be detected by obtaining the number of slits.
The slider 15 includes in the substantial center thereof a through hole 15a as illustrated in
Lower end portions of a pair of parallel shaft-like supporting members 32, 32 extending up and down are fastened to the transverse plate (bottom plate) 31 (refer to
A measuring element shaft 35 extending vertically is fitted into the guide tube 27 in a vertically movable manner, and a measuring element for a lens (a measuring element for a rim shape of a lens) 36 is integrally set in the upper end portion of the measuring element shaft 35. This measuring element for a lens 36 includes an L-shape having an attachment portion 36a vertically arranged in the upper end portion of the measuring element shaft 35 and a vertical portion 36b extending upward from the attachment portion 36a. A back face 36c of the vertical portion 36b is processed at a certain R. A measuring element for a lens frame 37 is integrally set in the upper end portion of the vertical portion 36b parallel to the attachment portion 36a.
A measuring element 38 for a mounting hole which projects upwardly is integrally set in the upper end of the measuring element for a lens 36 as illustrated in
A step face 38d as a corner measurement portion is arranged on the upper end of the measuring element attachment member 36 in the outer circumference of the base portion of the shaft-like measurement portion 38a. The edge corner of the lens Lm has contact with the corner between the shaft-like measurement portion 38a and the step face 38d when measuring the shape of the lens Lm by the measuring element for a lens.
As illustrated in
This linear scale 40 includes a shaft-like main scale 41 placed in parallel with the measuring element shaft 35 toward up and down and a detection head 42 which detects displaced positions of the measuring elements 37, 38 in the vertical direction from the displacement of the main scale 41 in the vertical direction. The main scale 41 has the upper end portion fastened to the holding member 33 and the lower end portion fastened (held) to the bracket 39. The detection head 42 is held by the holding member 33. For this linear scale 40, a magnetic scale or an optical scale can be adopted similar to the above-described linear scale 24.
As illustrated in
An elevation position control lever 49 is fastened to the supporting shaft 46. This elevation position control lever 49 controls an elevation position of the engagement shaft 44 by the pressure lever 47 and sets the elevation positions of the measuring element shaft 35 and the measuring element for a lens frame 37 and the measuring element for a lens 38. This elevation position control lever 49 extends in the direction which is the same as that of the pressure lever 47.
An actuator motor 50 is placed on the lower side of the elevation position control lever 49. This actuator motor 50 includes a motor main body 50a fastened on the transverse plate 31 and a shaft 51 which projects upwardly from the motor main body 50a and has the axis line parallel to the measuring element shaft 35. The elevation position control lever 49 has contact with the upper end of the shaft 51 by the tension spring force of the coil spring 48. In addition, a pulse motor is used for this actuator motor 50. The shaft 51 moves upwardly by the normal rotation of the actuator motor 50 and the shaft 51 moves downwardly by the reverse rotation of the actuator motor 50.
In addition, the coil spring 43, the supporting shaft 46, the pressure lever 47, the tension coil spring 48, the elevation position control lever 49, the actuator motor 50 and the like constitute the moving-up-and-down mechanism of the measuring elements 37, 38.
As illustrated in
A holder detector 53 as illustrated in
Hereinafter, a function of such a lens shape measurement device will be described.
(I) Measurement of a Lens Frame Shape
Before the measurement of a lens frame shape of eyeglasses or a lens shape such as a demo-lens is performed in the lens shape measurement device, the upper end of the shaft 51 of the actuator motor 50 is located in the lower end (bottom dead point) as illustrated in
When measuring a lens frame shape of eyeglasses by this lens shape measurement device, as described in JP H10-328992A, for example, an eyeglass frame MF having right and left lens frames LF (RF) in
The lens frames LF (RF) held between the holding bars 3b1, 3b2 are set to locate above the measuring element 37 for a lens frame before starting the measurement as illustrated in
In this position, the photosensor 9a detects the origin of the horizontal rotation of the rotation base 9 from the light flux from the light emitter 9b, and the origin sensor 20a detects the origin of the displaced position of the slider 15.
In addition, even if the lens frame is curved in the three dimensional direction, the held portion of the lens frame by the holding bars 3b1, 3b2 has a height which is the lowest in the lens frame. In this held portion, the height of the V-groove Ym of the lens frames LF (RF) becomes a set height, namely, a lens frame shape measurement start position B.
From this state, the start switch 54 in
Accordingly, the pressure lever 47 turns together with the supporting shaft 46, and the free end portion is elevated by a predetermined amount. By this elevation of the free end portion of the pressure lever 47, the engagement shaft 44 follows the free end portion of the pressure lever 47 to be elevated by the spring force of the coil spring 43, so that the measuring element shaft 35 is elevated by a predetermined amount.
The amount of elevation of the measuring element shaft 35, i.e., the amount of elevation of the shaft 51 by the actuator motor 50 becomes the amount L in which the leading end of the measuring element 37 for a lens frame is elevated to the height C facing the V-groove Ym in the above-described shape measurement start position (B) from the initial position (A) in
Then, the arithmetic control circuit 52 rotates the driving pulley 19 by controlling the driving of the driving motor 18, and displaces the slider 15 along the guide rail 14 by the wire 20 in
In addition, when the leading end of the measuring element 37 for a lens frame has contact with the V-groove Ym, the load on the driving motor 18 is increased, so that the current flowing in the driving motor 18 is increased. Therefore, it can be detected that the leading end of the measuring element 37 for a lens frame has contact with the V-groove Ym by detecting the current change, and thus, the driving motor 18 is stopped.
After that, the arithmetic control circuit 52 normally rotates the actuator motor 50, and displaces the shaft 51 by a predetermined amount to the position in
Accordingly, the pressure lever 47 turns together with the supporting shaft 46, the free end portion is elevated at predetermined amount, the free end portion of the pressure lever 47 moves away at predetermined amount from the engagement shaft 44, and the measuring element shaft 35 becomes vertically displaceable.
Next, the arithmetic control circuit 52 controls the driving of the driving motor 6 to normally rotate the driving motor 6. The rotation of the driving motor 6 is transferred to the driven gear 5 via the pinion 7 and the timing belt 8, so that the driven gear 5 horizontally rotates together with the rotation base 9 (refer to
With this rotation of the rotation base 9, the slider 15 and a number of components arranged in the slider 15 horizontally rotate together with the rotation base 9, and the leading end of the measuring element 37 for a lens frame slides along the V-groove Ym. In this case, since the slider 15 moves along the guide rail 14 together with the measuring element 37 for a lens frame, the displacement when the slider 15 is displaced from the origin position of the slider 15 becomes the same as the displacement of the leading end of the measuring element 37 for a lens frame. This displacement is obtained by the arithmetic control circuit 52 from the detection signal of the detection head 26 of the linear scale 24.
Moreover, since the measurement (length) from the center of the measuring element shaft 35 to the leading end of the measuring element 37 for a lens frame is known, if the distance from the rotation center of the rotation base 9 when the slider 15 is in the origin to the leading end of the measuring element 37 for a lens frame is set in advance, even if the distance from the rotation center of the rotation base 9 to the leading end of the measuring element 37 for a lens frame is changed when the slider 15 is displaced along the guide rail 14, the change in this distance can be a moving radius ρi.
Therefore, the shape (lens frame shape) of V-groove Ym of the lens frame LF (RF) in the circumferential direction can be obtained as lens frame shape information (θi, ρi) of a polar coordinate by obtaining the rotation angle θi of the rotation base 9 by the rotation of the driving motor 9 from the number of driving pulses of the driving motor 6 and obtaining the moving radius ρi corresponding to the rotation angle θi.
When the leading end of the measuring element 37 for a lens frame slides along the V-groove Ym, if the lens frame LF (RF) has a curvature in the vertical direction, the curvature state in the vertical direction is obtained as a displacement in the vertical direction by the arithmetic control circuit 52 from the detection signal of the detection head 42 of the linear scale 40. This displacement in the vertical direction becomes a position Zi in the vertical direction.
Consequently, the shape of the lens frame LF (RF) is obtained as three-dimensional lens frame shape information (θi, ρi, Zi) by the arithmetic control circuit 52. The obtained three-dimensional lens frame shape information (θi, ρi, Zi) is stored in a memory 55 by the arithmetic control circuit 52.
(II) Measurement of a Lens such as a Demo-Lens
(II-a) Setting of a Lens such as a Demo-Lens
When measuring a shape of right and left lenses Lm (ML), Lm (MR) (demo-lenses of dummy lenses of eyeglass lenses) of two-point fame eyeglasses M as illustrated in
A lens such as a demo-lens is held by the above-described lens holder, the lens holder is placed between the slider frames 3, 3, and the side wall of the lens holder in JP H10-328992A or the flange of the side portion in JP H08-294855A is sandwiched between the fastening holding bar 3b1 and the movable holding bar 3b2. In this case, the lens held by the lens holder is directed on the lower side.
In the two-point frame eyeglass 200 illustrated in
This bridge 201, as illustrated in
The attachment for a temple 202, as illustrated in
As illustrated in
The left fixing plate portion 201a of the bridge 201 is fixed to the lens Lm (ML) by a screw 204s inserted into the mounting hole 204, and the right fixing plate portion 201b of the bridge 201 is fixed to the lens Lm (MR) by a screw 205s inserted into the mounting hole 205. In addition, the fixing plate portion 202b of the attachment for a temple 202 is fixed to the lens Lm (ML) by a screw 206s inserted into the mounting hole 206, and the fixing plate portion 203b of the attachment for a temple 203 is fixed to the lens Lm (MR) by a screw 207s inserted into the mounting hole 207. Hereinafter, the lenses Lm (ML), Lm (MR) will be explained simply as the lens Lm.
(II-2) Contact Operation 1 of the Measuring Element for a Lens 36 to a Standard Lens
If the lens holder (not shown) is detected by the holder detector 53, this detection signal is input into the arithmetic control circuit 52. Thereby, the arithmetic control circuit 52 displaces the slider 15 forward along the guide rail 14 from the origin position, and locates the measuring element for a lens 36 on the outside of the rim of the lens held by the lens holder (not shown).
Next, the arithmetic control circuit 52 normally rotates the above-described actuator motor 50, so as to elevate the measuring element for a lens frame 37 from the initial position (A) to the height (B) illustrated in
After that, the arithmetic control circuit 52 controls the driving of the driving motor 18, and transfers the rotation of the driving motor 18 to the slider 15 by the wire 20, and controls the displacement of the slider 15 along the guide rail 14 such that the measuring element for a lens 36 is displaced to have contact with the circumferential face of the lens Lm held by the lens holder (not shown) as illustrated in
Such control can be performed according to standard lens data previously obtained by an experiment and the like.
(II-c) Contact Operation 2 of the Measuring Element 36 for a Lens to a Lens
In addition, another method can be used as the method which brings the measuring element for a lens 36 into contact with the circumferential face of the lens Lm. More specifically, at first, the actuator motor 50 normally rotates to lift the free end portion of the elevation position control lever 49 to the position in
The withdrawn position of the measuring element 36 for a lens out of the back side refracting surface of the lens Lm can be determined if the linear scale 40 detects the position when the measuring element for a lens 36 is elevated. The position of the horizontal direction of the measuring element for a lens 36 in the withdrawn position can be obtained from the detection signal of the linear scale 24. Therefore, by the detection signals from the linear scales 24, 40 in the withdrawn position, the position where the measuring element for a lens 36 separates from the back side refracting surface of the lens Lm can be obtained as three-dimensional coordinate data. In addition, by controlling the driving of the actuator motor 50 according to the three-dimensional coordinate data, the height of the free end portion of the elevation position control lever 49 is adjusted, and the height of the free end portion of the pressure lever 47 is adjusted. Consequently, the measuring element for a lens 36 can be adjusted to the height corresponding to the rim of the lens Lm held by the lens holder (not shown). After that, the arithmetic control circuit 52 controls the driving of the driving motor 18 to transfer the rotation of the driving motor 18 to the slider 15 by the wire 20, and controls the displacement of the slider 15 along the guide rail 14 such that the measuring element for a lens 36 is moved to have contact with the circumferential face of the lens Lm held by the lens holder (not shown) as illustrated in
(II-d) Measurement of a Rim Shape by the Measuring Element for a Lens 36
Next, the arithmetic control circuit 52 controls the driving of the driving motor 6 to normally rotate the driving motor 6. The rotation of the driving motor 6 is transferred to the driven gear 5 via the pinion 7 and the timing belt 8, so that the driven gear 5 horizontally rotates together with the rotation base 9.
With the rotation of the rotation base 9, the slider 15 and a number of components arranged in the slider 15 horizontally rotate together with the rotation base 9, and the measuring element for a lens 36 slides along the circumferential face (edge) of the lens Lm. In this case, since the slider 15 displaces along the guide rail 14 together with the measuring element for a lens frame 37, the displacement when the slider 15 displaces from the origin position of the slider 15 becomes the same as the displacement of the leading end of the measuring element for a lens frame 37. This displacement can be obtained by the arithmetic control circuit 52 from the detection signal of the detection head 26 of the linear scale 24.
Moreover, since the measurement (length) from the center of the measuring element shaft 35 to the leading end of the measuring element for a lens frame 37 is known, if the distance from the rotation center of the rotation base 9 when the slider 15 is in the origin to the leading end of the measuring element for a lens frame 37 is previously set, even if the distance from the rotation center of the rotation base 9 to the measuring element for a lens 36 is changed when the slider 15 is displaced along the guide rail 14, the change in this distance can be a moving radius ρi.
Therefore, the circumferential face shape (lens shape) of the lens Lm can be obtained as lens shape information (θi, ρi) of a polar coordinate by obtaining the rotation angle θi of the rotation base 9 by the rotation of the driving motor 6 from the number of driving pulses of the driving motor 6 and obtaining the moving radius ρi corresponding to the rotation angle θi.
As illustrated in
If such a lens is measured, depression is generated in a part of the lens data. Generally, the concave is placed at an upper half of the lens. Therefore, concave and convex by a measurement error and the concave for attachment are distinguished according to the conditions, and the position of the concave is detected. Next, the length Y in the central direction of the concave is measured by moving the measurement element for a mounting hole 38 in the lateral direction. The length can be input from an external input device.
(III) Measurement of a Curvature of the Back Side Refracting Surface of the Lens Lm
When only two dimensional lens shape information (θi, ρi) is obtained in the rim shape measurement (outer circumferential shape measurement) of the above described lens Lm, the curvature of the back side refracting surface fb of the lens Lm illustrated in
As illustrated in
In this Step S2, the arithmetic control circuit 52 measures the curvature of the back side refracting surface fb of the lens Lm illustrated in
In this case, the lens Lm is retained by a suction pad, and this suction pad is detachably attached to the not shown lens holder, so that the lens Lm is held by the lens holder. Moreover, in a state in which the lens holder is held between the lens frames 3, 3, it is set such that the vertically extending axis line (not shown) of the suction pad of the lens holder is aligned with the vertically extending axis line (shaft line O in
As illustrated in
In such a condition, the arithmetic control circuit 52 controls the operation of the driving motor 18, and displaces the slider 15 along the guide rail 14 by the wire 20 which works with the driving motor 18, and the upper end (leading end) of the measuring element 36 for a lens is sequentially moved to the measurement points P2, P1 of the radius direction (X direction) of the lens Lm. This measurement point P2 is a position which is moved in the radius direction (X direction) of the lens Lm at a distance X2 from the origin X0 in the X direction, and the measurement point P1 is a position which is moved in the radius direction (X direction) of the lens Lm at the distance X1 (X1>X2) from the origin X0 in the X direction.
In this case, the arithmetic control circuit 52 calculates the heights Z2, Z1 in the Z direction (vertical direction) in the distances X2, X1 of the back side refracting surface fb of the lens Lm from the displacement detection signal from the linear scale 40, and the operation moves to Step S3. The heights Z2, Z1 in the Z-direction are distances from the origin Z0 in the Z-direction.
Step 3
In this Step 3, the arithmetic control circuit 52 obtains a curve value from the curvature of the back side refracting surface fb of the lens Lm. In this case, where the distance from the curvature center O1 of the back side refracting surface fb of the lens Lm to the origin Z0 in the Z-direction is ΔZ, the height from the curvature center O1 to the measurement point P2 is Z1+ΔZ and the height from the curvature center O1 to the measurement point P1 is Z2+ΔZ. Therefore, the coordinate of the measurement point P2 is (X2, Z2+ΔZ) and the coordinate of the measurement point P1 is (X1, Z1+ΔZ).
The arithmetic control circuit 52 calculates by using a circular equation in order to obtain a curvature from the coordinate (X2, Z2+ΔZ) of the measurement point P2 and the coordinate (X1, Z1+ΔZ) of the measurement point P1. The circular equation is as follows where the curvature radius diameter of the lens Lm is R.
X
2
+Z
2
=R
2
The equation passing through the measurement point P1 from this equation is as follows.
(X1)2+(Z1+ΔZ)2=R2 (1)
The equation passing through the measurement point P2 is as follows.
(X2)2+(Z2+ΔZ)2=R2 (2)
The following equation is obtained from (1)-(2).
(X1)2−(X2)2+(Z1+ΔZ)2−(Z2+ΔZ)2=0
Then, the following equation is obtained by developing the above equation.
(X1)2−(X2)2+(Z1)2+2(Z1)·ΔZ+ΔZ2−(Z2)2−2(Z2)·ΔZ−ΔZ2=0
And, the following equation is obtained.
(X1)2−(X2)2+(Z1)2+2(Z1)·ΔZ−(Z2)2−2(Z2)·ΔZ=0
Then, the following equation is obtained if the above equation is simplified by combing ΔZ.
[2(Z1)−2(Z2)]ΔZ=(X2)2−(X1)2+(Z2)2−(Z1)2
ΔZ can be obtained from this equation. Namely, ΔZ is as follows.
The above is obtained.
Meanwhile, the curve value of the eyeglass lens is set within a range from the curve of 1 to the curve of 8 as illustrated in
Where the above X1=10 mm and the above X2=5 mm, the Z-direction difference ΔL (ΔL−ΔL8) of the measurement points P1, P2 can be obtained corresponding to the curve of 1 to the curve of 8 as illustrated in Table 1. In other words, where the Z-direction difference (ΔL in
In addition, the Z-direction difference (ΔL in
Curve value=3.3695×Z-direction difference ΔL+0.0809
The relationship between the curve value Cv and the Z-direction difference ΔL (ΔL1−ΔL8) is linearly proportional as illustrated in
As described above, the arithmetic control circuit 52 obtains the curve value of the back side refracting surface fb of the lens Lm, and the operation moves to Step S4.
Step 4
In Step S4, the arithmetic control circuit 52 obtains the positional information Zbi in the Z-direction of the rim of the back side refracting surface fb of the lens Lm from the curve value Cv obtained according to the Z-direction difference ΔL (ΔL1−ΔL8) and the lens shape information (θi, ρi), and the operation moves to Step S5.
Step 5
In Step 5, the arithmetic control circuit 52 obtains the three-dimensional lens shape information (θi, ρi, Zbi) from the two-dimensional lens shape information (θi, ρi) and the positional information Zbi of the Z-direction of the rim of the back side refracting surface fb of the lens Lm obtained in Step S4, and the step is completed. The obtained three-dimensional lens shape information (θi, ρi, Zbi) is stored in a memory 55 by the arithmetic control circuit 52.
(IV) Measurement of a Position of a Mounting Hole of a Lens Lm
Next, as illustrated in
Where the lens Lm of the three-dimensional shape information (θi, ρi, Zbi) obtained by the measurement in the above-described (II), (III) is lens Lm (ML) in
This mounting hole detection areas (sensing areas) Sa, Sb are set between right and left ends Pa, Pb of the les Lm (ML) and positions a1, a2 which are located inside at at a predetermined distance La from the right and left ends Pa, Pb in the right and left direction. These predetermined areas sa, sab are set inside by a predetermined amount a (for example, 1 mm) from the outer circumferential face of the lens Lm as illustrated in
After that, the arithmetic control circuit 52 scans (moves) in a zigzag the lens measuring element for a mounting hole 38, which has contact with the back side refracting surface, in the mounting hole detection areas Sa, Sb as illustrated by arrows A1, A2 in
Such movement of the measuring element for a mounting hole 38 in the horizontal direction is performed by controlling the driving of the driving motor 6 and the driving of a pulse motor (not shown) which moves the not shown entire base in
In a case that the measuring element for a mounting hole 38 is moved in zigzag as described above, if the measuring element for a mounting hole 38 is moved in the direction illustrated by arrows B1, B2 in
If a part of the measuring element for a mounting hole 38 enters into the mounting hole 206, the displacement of the measuring element for a mounting hole 38 in the upward direction significantly changes in a position illustrated in P as the vertical position change curve in
Thus, the arithmetic control circuit 52 stores the central position of the position P as the three-dimensional position information (θi, ρi′, Zi′) of the mounting hole 206 in the memory 55 to be mounting hole position processing data (data for opening a hole).
In addition, the mounting holes 204, 205, 207 are similarly measured.
The above embodiment has a structure such that the bridge 201, as illustrated in
For example, Modified Example 1 may have a structure such that the bridge 201, as illustrated in
In this case, the curvature of the front side refracting surface and the circumferential length of the edge face of the lenses Lm (ML), Lm (MR) are measured in the same manner as the back side refracting surface of the lens Lm as described above, and positions of the mounting holes 204-207 are measured.
In
In the above embodiment, the mounting hole detection areas (sensing areas) Sa, Sb which extend vertically in the right and left portions of the lens Lm are set; however, the mounting hole detection areas are not limited to the above embodiment. For example, as illustrated in
As illustrated in
As typical examples, positions where the mounting holes 204 to 207 and the like are formed to the shape of the lens Lm are positions which are closer to an upper side of right and left end portions of the lens Lm, or positions which are closer to the center portion in the vertical direction of the right and left end portions of the lens Lm. Accordingly, it is preferable to provide a switch for selecting a detection position (mounting hole detection area) in right and left upper end portions, a center portion in the vertical direction or the like of the lens Lm, and it is preferable to set the mounting hole detection area (sensing area) Sc based on the selected detection position by this switch and the lens shape information (θi, ρi, Zbi) of the lens.
Namely, the mounting hole detection area (sensing area) Sc can be set as follows. For example, the lower portion, the side face and a part of the upper portion of the device main body 1 in
Moreover, the switches Sa, Sb which select the mounting hole detection areas Sb1, Sb2 are set in the main body case Hc. The arithmetic control circuit 52 selects the mounting hole detection area Sc1 if the switch Sb1 is pressed, and selects the mounting hole detection area Sc2 if the switch Sb2 is pressed.
In addition, instead of setting the switches Sb1, Sb2, a “− +” switch Sa or a “Δ” cursor key c1 and a “▾” cursor key c2 is provided in the key board Kb, and the arithmetic control circuit 52 can set to select the mounting hole detection areas Sc1, Sc2 upon the operation of the “− +” switch Sa or a “Δ” cursor key c1 and a “▾” cursor key c2.
As illustrated in
In addition, as illustrated in
As described above, the lens shape measurement device according to the embodiment of the present invention includes the lens holder (not shown) set in the measuring device main body 1, the measuring element for a lens 36 which measures the rim shape of the lens Lm held in the lens holder (not shown), the measuring element shifter (driving motor 6) which shifts the measuring element for a lens along the outer circumferential face of the lens Lm, the first position detector (linear scale 24) which detects a position along the outer circumferential face of the measuring element 36 for a lens, the second position detector (linear scale 40) which detects a position in the direction orthogonal to the first position detector (linear scale 24), and the arithmetic control circuit 52 which obtains the circumferential face shape data of the lens Lm as three-dimensional information according to the detection signal from the first and second detectors (linear scales 24, 40). By moving the leading end of the measuring element for a lens 36 to have contact with the refracting face of the lens Lm held in the lens holder (not shown), the arithmetic control circuit 52 detects a relationship between the rim shape and the hole position of the lens according to the detection signal from the second position detector (linear scale 40).
According to the above configuration, the position of the mounting hole for mounting the attachment of the two-point frame to the lens can be easily and accurately measured.
The lens shape measurement device according to the embodiment of the present invention is configured to detect by the rim shape of the lens the position of the concave of the lens having the mounting hole for the attachment and the concave on the rim.
According to the above configuration, the concave is formed on the rim of the lens shape, and the attachment of the two-point frame can be attached by using this concave.
In the lens shape measuring device according to the embodiment of the present invention, the measuring element for detecting the mounting hole of the lens for the attachment can be constituted by a member which is different from the measuring element for measuring the rim shape.
According to the above configuration, the measuring element for detecting the mounting hole of the lens for attachment (the measuring element for a mounting hole 38) and the measuring element for a lens 38 can be easily processed.
Moreover, as described above, in the lens shape measuring device according to the embodiment of the present invention, the arithmetic control circuit 52 sets the mounting hole detection area (Sa, Sb, Sc and the like) in a position which is inside by a predetermined amount from the outer circumferential face of the lens Lm according to the lens shape data. According to this configuration, the measuring element for a mounting hole 38 is prevented from being deviated from the lens Lm upon detecting the mounting holes 204, 206 by moving the measuring element for a mounting hole 38 in the mounting hole detection area Sa, Sb, Sc.
In the lens shape measuring device according to the embodiment of the present invention, the arithmetic control circuit 52 sets the mounting hole detection area (Sa, Sb) in the right and left portions of the lens Lm according to the lens shape data. According to this configuration, the mounting hole detection area (Sa, Sb) is narrowed, so that the detection time can be reduced.
In the lens shape measuring device according to the embodiment of the present invention, the arithmetic control circuit 52 sets the mounting hole detection areas (Sc) on the right and left end portions of the upper side of the lens Lm according to the lens shape data. According to this configuration, the detection time can be reduced compared to a case when the mounting hole detection areas are set in the entire of the right and left portions.
In the lens shape measuring device according to the embodiment of the present invention, the arithmetic control circuit 52 sets the mounting hole detection area (Sc) in the central portions of the right and left end portions of the lens in the vertical direction according to the lens shape data. According to this configuration, the detection time can be reduced compared to a case when the mounting hole detection areas are set in the entire of the right and left portions.
The lens shape measuring device according to the embodiment of the present invention includes a detection area selector (switch Sb1, Sb2, “− +” switch Sa, or “Δ” cursor key c1 and “▾” cursor key c2) which selects the right and left end portions of the upper side of the lens Lm or the central portion of the right and left end portions of the lens Lm in the vertical direction as the mounting hole detection area (Sc), and the arithmetic control circuit 52 sets the right and left end portions of the upper side of the lens or the central portion of the right and left end portions of the lens in the vertical direction as the mounting hole detection area (Sc) by the selection operation of the detection area selection device (switch Sb1, Sb2, “− +” switch Sa or “Δ” cursor key c1 and “▾” cursor key c2). According to this configuration, a plurality of mounting hole detection areas can be simply selected and set.
The lens shape measuring device according to the embodiment of the present invention includes the liquid crystal display which displays the shape of the lens Lm and the detection area input device (touch panel, cursor operation switch c3 and the like) which inputs the mounting hole detection area in the lens Lm displayed on the liquid crystal display, and the arithmetic control circuit 52 sets the mounting hole detection area according to the input of the detection area input device. According to the above configuration, the mounting hole detection area can be selected corresponding to the mounting hole, so that it can correspond to a lens in which the position of the mounting hole is not standard.
In the lens shape measuring device according to the embodiment of the present invention, the detection area input device is a touch panel provided in the liquid crystal display, and the arithmetic control circuit 52 displays a mark (cross mark 222) illustrating the center of the detection area on the liquid crystal display, and sets the mounting hole detection area centering on the mark (cross mark 222) of the center of the detection area on the touched portion of the touch panel. According to this configuration, the mounting hole detection area can be selected corresponding to the mounting hole without providing a switch and the like for selecting, so that it can correspond to a lens in which the position of the mounting hole is not standard.
Number | Date | Country | Kind |
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2007-326787 | Dec 2007 | JP | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/JP2008/073046 | 12/18/2008 | WO | 00 | 1/6/2011 |