JP3345149B2 - Aspherical lens eccentricity measuring device and centering device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aspherical lens eccentricity measuring apparatus for measuring the eccentricity of an aspherical optical lens, which is caused by molding errors, centering errors, and the like, and a centering apparatus using the same.

[0002]

2. Description of the Related Art As an apparatus for measuring the eccentricity of an aspherical lens, an apparatus for measuring the eccentricity by rotating a test lens (an aspherical lens to be measured for eccentricity) and measuring the shake thereof, For example, there is known an eccentricity measuring apparatus for a single-sided aspherical lens as disclosed in Japanese Patent Application Laid-Open No. 1-296132. In this eccentricity measuring device, the center of curvature of the spherical surface of the test lens is made to coincide with the rotation axis of the holder that supports the test lens, and the holder is rotated in this state, and the aspherical surface of the The shake, that is, the eccentricity of the aspherical axis with respect to the rotation axis of the holder was measured.

[0003] However, such a conventional eccentricity measuring apparatus does not include a positioning means for accurately aligning the aspherical axis of the aspherical surface with the rotation axis of the holder. It has been limited to aspheric lenses, that is, aspheric lenses in which one surface is necessarily spherical.
For this reason, there has been a problem that the measurement of a double-sided aspheric lens cannot be performed.

[0004]

SUMMARY OF THE INVENTION In view of the above problems of the prior art, the present invention provides
An object of the present invention is to provide an eccentricity measuring device capable of measuring the eccentricity of a double-sided aspheric lens and a centering device using the same. For this purpose, the present invention provides an eccentricity measuring device and a centering device provided with means for matching the aspherical axis of one aspherical surface of the double-sided aspherical lens to the rotation axis of the aspherical lens support means. Aim.

[0005]

According to the first aspect of the present invention, which achieves the above object, a rotating means for producing a rotating axis serving as a reference for measurement, and a rotating means for contacting the peripheral portion of the aspherical surface of the aspherical lens to be measured. An aspheric lens supporting means rotated by the rotating means while supporting the inspection aspheric lens, and the aspheric surface or the
Select an optical index image on the opposite surface along the rotation axis.
Projected and reflected from the aspheric surface or the opposite surface
The aspheric surface with respect to the rotation axis based on the reflected image
Displacement of the central part of the surface and the surface opposite to the aspheric surface
Detecting means for detecting eccentricity with respect to the rotation axis;
In accordance with the detected value of the detecting means, the eccentricity of the aspherical lens characterized in that it comprises a non-spherical lens position adjusting means for moving and adjusting the direction substantially perpendicular to said subject an aspheric lens with respect to said rotation axis It is a measuring device.

The present invention described in claim 5 has no claim 1
5. The apparatus for measuring eccentricity of an aspheric lens according to any one of items 4 to 5, and lens outer peripheral processing means for processing an outer circumference of the aspheric lens to be tested into a shape determined with respect to the rotation axis. A centering device for an aspherical lens.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on illustrated embodiments. FIG. 1 is a block diagram showing a main part of an embodiment of an aspherical lens eccentricity measuring apparatus to which the present invention is applied. This eccentricity measuring device is roughly divided into a lens support rotation block 10 for supporting and rotating the lens to be inspected, an eccentricity measuring block 30 for measuring the eccentricity and inclination of the lens to be inspected, and a measurement result of the eccentricity measuring block 30. A lens position adjusting block 60 for performing fine adjustment of the position of the lens to be inspected manually or under the control of the control block 70, and measuring and calculating the position of the lens to be inspected and the eccentricity of the aspheric surface, and displaying the calculation result, etc. And a control block 70 for controlling the above means. Here, the test lens is a double-sided aspheric lens to be measured for eccentricity.

The lens support rotation block 10 is a device for rotating the aspherical axis of one aspherical surface of the aspherical lens 21 to be inspected, which is the lens to be inspected, so as to coincide with the rotational axis of the aspherical lens support means. This lens support rotating block 10
Is a hollow turntable 13 (rotating means) driven to rotate by a motor 11, a cylindrical lens support 15 (aspherical lens supporting means) fixed on the turntable 13, and a turntable 13 A rotary encoder 17 that detects the rotation of the lens, a suction device 19 that sucks air through the turntable 13 and the hollow portion of the lens support 15 to be suctioned and fixes the aspherical lens 21 to be fixed to the lens support 15. It has.

The rotation axis of the turntable 13 and the center axis of the lens support 15 are positioned so as to exactly coincide with each other. The lens contacting edge 16 of the lens support 15 to be inspected against which the aspherical lens 21 contacts is positioned on a plane that is concentric with the central axis of the lens support 15 and orthogonal to the central axis. I have. A central axis this passing through the axis of rotation of the central shaft and the turntable 13 of the lens supporting device 15, hereinafter referred to as the rotation axis Z _0. In addition, the turntable 13 which is a rotating means may be constituted by a static pressure air spindle or the like. Further, the motor 11 for rotating the turntable 13 is not essential, and may be omitted depending on the application and the turntable 13 may be rotated manually.

The eccentricity measuring block 30 has a light projecting / observing optical system for observing an image by autocollimation reflection on a surface having a paraxial curvature at the center of the aspheric surface. In this embodiment, both aspherical surfaces of the aspherical lens to be inspected can be switched and observed by one light projecting / observing optical system. The configuration and operation of this embodiment are as follows.

The laser beam output from the laser light source 31 passes through a beam splitter 33 and is condensed by a first condenser lens 35 to form a point light source (index) 37.
The laser beam diverged from the point light source 37 is converged by the second condenser lens 39, and when the optical path switching mirror 41 as the optical path switching means is retracted out of the optical path, the first mirror 43 Is reflected toward the aspherical lens 21 to be inspected, and the aspherical surface on the side (lower side in FIG. 1) of the aspherical lens 21 to be in contact with the lens contacting edge 16 of the lens support 15 of the inspected lens support 15. Irradiated at the center. And the laser beam
The light is reflected at the central portion of the aspheric surface, travels backward in the optical path, and is reflected by the first mirror 43 toward the second condenser lens 39. Second
When the light enters the condenser lens 39, the light is converged on or near the point light source 37, diverges, is converted into a parallel light beam by the first condenser lens 35, and is then substantially perpendicular to the laser light source 31 direction by the beam splitter 33. Is reflected by
Then, the light enters the video camera 51 via the imaging lens 49 and is imaged by the video camera 51. The reflected image of the point light source 37 captured in this manner is displayed on the monitor television 53 as a reflected image 37i. That is, the eccentric measurement block 30 in this case, the detection for detecting a position displacement of the central portion of the aspherical surface on the side in contact with the lens abutment edge 16 of the lens supporting device 15 of the subject aspheric lenses 21 Acts as a means .

The first condenser lens 35 and the second condenser lens 39 are configured so that the relative distance along each optical axis can be adjusted.
The image forming position 7 is adjusted so as to be substantially conjugate with the center of the paraxial curvature at the center of the lower aspheric surface of the aspheric lens 21 to be measured.

On the other hand, when the optical path switching mirror 41 is entering the optical path, the laser beam emitted from the point light source 37 is substantially parallel to the rotation axis Z ₀ of the lens support 15 by the optical path switching mirror 41. The light is reflected upward, and is irradiated by the second and third reflection mirrors 45 and 47 toward the central part of the aspheric surface on the upper side of the aspheric lens 21 to be measured. Then, the light is reflected by the central part of the aspherical surface on the upper side of the aspherical lens 21 to be examined, travels backward in the optical path, and is reflected by the third and second reflecting mirrors 47 and 45 and the optical path switching mirror 41 in the direction of the second condenser lens 39. Is done. Then, similarly to the above, the image is taken by the video camera 51 through the second condenser lens 39, the first condenser lens 35, the beam splitter 33, and the imaging lens 49, and is displayed on the monitor television 53. That is, in this case, the eccentricity measurement block 30 serves as eccentricity detection means for the central portion of the upper aspheric surface. Note that, at this time, the relative distance and position of the first condenser lens 35 and the second condenser lens 39 are such that the imaging position of the point light source 37 by the first condenser lens 35 is above the aspheric lens 21 to be measured. Are adjusted so as to be substantially conjugate with the paraxial center of curvature of the central part of the aspheric surface.

Here, the paraxial center of curvature of the central portion of the aspherical surface of the aspherical lens 21 to be irradiated with the laser beam coincides with the central axis (rotation axis Z ₀ ) of the lens support 15. , The reflection image 37i of the point light source 37 is located substantially at the center of the monitor television 53. That is, when the aspherical central portion on the side where the laser beam is irradiated is eccentrically or inclined with respect to the rotation axis Z ₀ (tilt), the reflected image 3 on the monitor television 53
7i is shifted from the center of the screen. When the test aspheric lens 21 rotates, it rotates on the screen in accordance with the rotation, so that the eccentric state of the central portion of the aspheric surface can be determined from the amount of movement. Here, the video camera 51 is connected to the image processing circuit 55.

The eccentricity measuring block 30 has another eccentricity detecting means for detecting the eccentricity of the aspherical surface above the aspherical lens 21 to be measured. The configuration is as follows. An electric pick sensor 57 (eccentricity detecting means) that is in contact with the periphery of the upper surface of the aspherical lens 21 to be inspected is arranged near the lens support 15 to be inspected. The electric pick sensor 57 measures the height of a contact portion that moves with rotation, that is, the surface deflection of the peripheral portion of the upper aspheric surface of the aspheric lens 21 to be measured. In other words, the eccentric state of the peripheral part of the aspherical surface can be known from the measured amount of surface runout.

In the present embodiment, while observing the reflection image 37i from the center of the aspherical surface of the lens holder 15 to be in contact with the lens contacting edge 16, the turning radius is gradually reduced. Finally, the position of the aspherical lens 21 to be measured is adjusted by the lens position adjusting block 60 so as not to rotate. At this time, the periphery of the aspherical surface is located at the rotation axis Z _0.
And a line contact is made circumferentially with the lens contacting edge portion 16 located on a plane concentric with the rotation axis Z ₀ and the aspherical axis of the aspheric surface coincides with the rotation axis Z ₀ . After this manner to match the aspheric axis of the aspherical surface to the rotation axis Z _0, characterized in that for detecting the eccentricity condition of the other aspherical surface.

The structure of the lens position adjusting block 60 is as follows. An electric micrometer 61 (aspherical lens position adjusting means) is disposed near the test lens support 15 and at a position facing the outer peripheral portion of the test aspheric lens 21 placed on the test lens support 15. ing. The electric micrometer 61 moves the spindle 62 forward and backward under the control of the controller 63 in a direction orthogonal to the rotation axis Z ₀ , and when the spindle 62 advances, the tip of the spindle 62 contact with the outer peripheral surface, pressed test in a direction substantially perpendicular to the rotation axis Z ₀ aspherical lens 21
Adjust the position of. In this position adjustment, the aspherical lens 21 moves while maintaining a state in which the surface in contact with the lens contact edge 16 and the lens contact edge 16 are almost in line contact.

One or more electric micrometers 61 may be provided. One case is the subject lens supporting device 15 the aspherical aspherical axis subject aspherical lenses so as to press the subject aspheric lens 21 from the direction is most deviated with respect to the rotation axis Z ₀ of the Adjustment is made after the rotation position of 21 is determined.
In the case of a plurality of electric micrometers 61, the position is adjusted in the same manner as described above, or the moving amount of the spindle 62 of the plurality of electric micrometers 61 is combined to produce the aspheric surface to be measured. The position of the lens 21 is adjusted.

Further, the control block 70 shown in this embodiment
Controls the above members, the upper surface of the aspherical lens 21 to be measured, that is, the aspherical surface opposite to the aspherical surface,
A computer 71 for analyzing and displaying an eccentric state with respect to the rotation axis Z ₀ is provided.

The computer 71 includes an image processing circuit 5
5 and the position data of the reflection image 37i of the point light source 37 via the interface 79, and the surface deflection data detected by the electric pick sensor 57 via the interface 73, and further from the rotary encoder 17 via the interface 75. The rotation position data of the turntable 13 is input. Then, the eccentric state of the upper surface of the aspherical lens 21 is analyzed from these data, that is, the position data of the reflection image 37i, the surface deflection data detected by the electric pick sensor 57, and the rotation position data of the turntable 13. The result is displayed as a numerical value or a graph. The computer 71 controls the projecting timing and amount of projection of the spindle 62 of the electric micrometer 61 through the interface 77 and controller 63, in the direction substantially perpendicular to the rotation axis Z ₀ the test aspherical lens 21 Move to perform positioning adjustment.

In the above embodiment, first, one aspherical surface of the aspherical lens 21 to be inspected is brought into contact with the lens contacting edge 16 of the lens holder 15 to be inspected, and a reflection image 37i from the central portion of the aspherical surface is obtained. While observing, the aspherical axis of the aspherical surface is made to coincide with the central axis of the lens support 15 to be measured, that is, the rotation axis Z ₀ of the turntable 13 by the electric micrometer 61. And next, the aspheric opposite aspherical, computer 71 an eccentric with respect to the rotation axis Z ₀ is, electrical pick sensor 57 detects vertical deviation data, the position data of the reflected image 37i, and the turntable Analyzed from 13 rotation position data and displayed.

FIGS. 2 and 3 show another embodiment of the aspherical position detecting means. The second embodiment of FIG. 2 is an example of an auto-collimation reflection type in which a point light source is projected on the center of the aspheric surface and a reflected point light source image is observed. The third embodiment of FIG. It is an example of the magnification observation type | formula which magnifies and observes a spherical center part through a magnifying glass (microscope).

The reflection type aspherical position detecting means shown in FIG.
An aspherical axis detection optical system 30a for detecting the aspherical axis of the surface (aspherical surface 22) on the side of the first lens contact edge 16 is provided.
The aspherical axis detection optical system 30a reflects the laser beam output from the laser light source 81 toward the aspherical lens 21 to be measured by the beam splitter 82, and the first condensing lens 83
To form a point light source. The laser beam diverged from this point light source is condensed by the second condensing lens 84, and the target aspheric lens 2
The light is projected on the central portion of one aspherical surface 22. The laser beam reflected at the center of the aspherical surface 22 travels backward in the optical path, passes through the condenser lenses 84 and 83, and the beam splitter 82, and is formed on the two-dimensional position sensor (PSD) 86 by the imaging lens 85. Image. By detecting the image formation position of the point image by the two-dimensional position sensor 86, the aspheric axis of the lower surface (aspheric surface 22) of the aspheric lens 21 to be measured can be detected.

Further, in this reflection type embodiment, the aspherical axis is detected above the aspherical lens 21 to be measured so that the eccentricity of the center of the upper surface (aspherical surface 23) of the aspherical lens 21 to be measured can be measured. An aspherical axis detection optical system (eccentricity detection means) 30b similar to the optical system 30a is provided.

The magnifying observation type aspherical position detecting means according to the third embodiment shown in FIG. 3 is, for example, a plastic aspherical lens molded by a rotationally symmetrical aspherical die. In this configuration, the vertex (so-called navel) of the center of the aspherical surface formed by cutting marks at the center of the aspherical surface is magnified and observed to detect the aspherical axis of the lower surface (aspherical surface 22). In the aspherical surface position detecting means, as shown in FIG. 3, the subject side of the surface where the rotational shaft Z ₀ match the aspherical axis of the aspherical lens 21 (aspheric surface 22 side) down to the sample lens supported Place on a container 15. Then, the rotation axis Z ₀ of the lens support 15 to be measured.
The central part of the aspherical surface 22 of the aspherical lens 21 to be inspected is enlarged by the magnifying objective lens whose optical axis coincides with the optical axis, for example, the objective lens 91 of the microscope, and the image is formed on the image sensor 93 of the video camera 95. Image. And aspheric surface 22
The image of the vertex at the center of is displayed on, for example, the monitor television shown in FIG. 1 and the deviation of the vertex (the image) from the rotation axis is detected.

In the third embodiment, the electric pick-up sensor 57 (eccentricity detecting means) detects the surface deflection of the peripheral portion of the aspherical surface 23 on the side not in contact with the lens support 15 to be measured. Although not shown in FIG. 3, a configuration may be adopted in which the eccentricity of the central portion of the other aspherical surface 23 is measured by observing the vertex of the central portion of the aspherical surface by the same detection means as in the magnifying observation method described above.

The adjustment of the position of the aspherical lens 21 to be performed based on the eccentricity detected by the aspherical position detecting means shown in FIGS. 2 and 3 is the same as that of the embodiment shown in FIG.

In the third embodiment shown in FIG. 3, the electric pick sensor 59 is connected to the aspherical lens 2 to be inspected due to the rotation.
1 is detected. The peripheral vibration data detected by the electric pick sensor 59 as the peripheral vibration detecting means is input to a computer (not shown) via an interface (not shown). The computer also calculates and displays in detail the aspherical axes of both aspherical surfaces 22 and 23 of the aspherical lens 21 to be inspected and the eccentric state of the three members on the outer periphery of the lens by calculating the outer peripheral shake data together. Can be. It should be noted that the outer peripheral shake detecting means can be applied to the first and second embodiments shown in FIGS.

In the above embodiments, the measurement of the eccentricity of the double-sided aspherical lens has been described. However, these embodiments can also measure the eccentricity of the single-sided aspherical lens. In this case, the aspherical side of the one-sided aspherical lens is placed on the lens support 15 to be tested, and the aspherical axis of the aspherical surface is rotated by the method described in the above embodiment. Align with axis Z ₀ . Then, the eccentricity of the spherical surface at that time is detected.
However, in this case, since the surface to be measured is a spherical surface, any one of eccentricity detecting means such as light projection to the central portion of the spherical surface, an observation optical system, or a surface deflection detecting sensor at the peripheral portion of the spherical surface may be used.

FIG. 4 shows a main part of a fourth embodiment of the present invention. This fourth embodiment is similar to the first embodiment shown in FIG. 1 except that a rotating unit, an aspherical lens support unit, an aspherical position detecting unit, and an aspherical lens position adjusting unit are used. A three-dimensional position measuring device 150 is provided as eccentricity detecting means for detecting the eccentricity of the upper aspherical surface 23 of the spherical lens 21 which does not contact the lens support 15 to be measured.

The three-dimensional position measuring device 150 has an XYZ
A probe 152 that moves in three directions perpendicular to each other is provided. The probe 152 is moved to measure the three-dimensional coordinates of the aspheric surface 23 of the aspheric lens 21 to be measured.
Further, the three-dimensional position measuring device 150 includes a lens holder to be tested which has been processed concentrically with respect to the central axis (rotation axis Z ₀ ) of the lens holder 15 to be tested in addition to the upper aspheric surface 23. The position coordinates of the surface of the outer peripheral surface 15a of the test object 15 or the outer periphery of the aspherical lens 21 to be measured are measured, and the position coordinate data is output to the computer 71 via the interface 151.

In the eccentricity measurement in this embodiment, first,
Similarly to the first embodiment, the rotating means, the aspherical lens supporting means, the aspherical position detecting means, and the lens position adjusting means are operated to change the aspherical axis of the lower aspherical surface 22 to the rotation axis Z.
Match ₀ . Thereafter, the coordinate data is measured by the three-dimensional position measuring device 150, and based on the coordinate data, the computer 71 operates the lens holder 15 to be measured.
The eccentricity of the aspherical surface 23 on the upper side of the aspherical lens 21 to be measured with respect to the central axis is analyzed and displayed.

Next, a description will be given of an aspheric lens centering apparatus according to another embodiment of the present invention, which is an application of the aspheric lens eccentricity measuring apparatus, with reference to the embodiments shown in FIGS. This centering device shows only the main part, but FIG.
In the embodiment of the apparatus for measuring the eccentricity of the aspherical lens shown in FIG. 1, a lens outer periphery processing means 120 for processing the outer periphery of the aspherical lens 21 to be inspected is added.
Aims at processing the outer periphery of a predetermined shape with respect to the rotation axis Z ₀ of the subject lens supporting device 15.

The lens outer periphery processing means 120 includes a disk-shaped grindstone 122 for grinding the outer periphery of the aspherical lens 21 to be tested, a motor 123 for rotating the grindstone 122, and a rotation axis Z _{0 of the} lens support 15. And an XY electric stage 124 for integrally moving the grindstone 122 and the motor 123 in an XY plane perpendicular to the XY plane. The XY electric stage 124 operates by inputting a control signal from the computer 71 via the interface 125.

In this embodiment, the aspherical lens to be centered is first placed on the lens support 15 with the aspherical surface on the side where the eccentricity is desired to be reduced to the outer periphery of the lens at the end of the centering process. Put on. Next, as described in the embodiment shown in FIG. 1, the rotating means (the turntable 13), the aspherical position detecting means (the eccentricity measuring block 30), and the aspherical lens position adjusting means (the electric micrometer 61) are used. operation to, match aspherical axis aspheric the lower to the rotation axis Z _0. Then, while the grindstone 122 is rotated at a constant speed by the motor 123, the computer 71 controls the position of the XY electric stage 124 to perform centering. At this time,
As shown in FIG. 6, the XY motorized stage 124 so as to keep the rotation axis Z ₀ a constant distance d to the grindstone 122 performs positioning of the wheel 122, the sample lens supporting device for supporting a subject aspheric lenses 21 When the motor 15 and the turntable 13 are rotated slowly, the aspherical lens 21 to be measured is centered in a circular shape having a diameter of φ2d.

Further, as shown in FIG. 7, Keep in stopping the rotation of the aspheric surface lens 21, linearly slowly move the grindstone 122 in a plane perpendicular to the rotation axis Z ₀ by the XY motorized stage 124 Then, the aspheric lens 21 to be inspected
Can be machined linearly. Therefore, if this processing is performed a total of four times by rotating the test aspheric lens 21 by 90 °, the test aspheric lens 21 is centered in a square.
At this time, the distance d from the rotation axis Z ₀ to the grinding wheel 122 is d.
Alternatively, if the rotation angle (stop angle) of the test aspheric lens 21 is arbitrarily set, various shapes such as a rectangle and a polygon can be centered.

As described above, according to the aspherical lens centering device of the present embodiment shown in FIG. 5, it is possible to center the aspherical lens into a shape determined with respect to the aspherical axis of one of the aspherical surfaces. Easy to do.

Here, the relationship between the amount of aspherical surface and the analysis error in this embodiment will be described with reference to FIGS. FIGS. 8 to 10 show an ideal single-sided aspheric lens 101 having no decentering. Here, “ideal” means a state in which the aspherical axis, the center of curvature of the spherical surface, and the center of the lens outer shape are all aligned on the same straight line.

The eccentricity measurement of the conventional aspherical surface, generally, to measure one rotating axis Z ₀ the deflection of the central portion and the peripheral portion of the aspherical surface for separately. For this reason, especially when the amount of aspherical surface is small, such a small error of the measurement value obtained by the separate measurement may cause a large analysis error. The details will be described with reference to FIGS.

Here, it is assumed that the amount of aspherical surface of the ideal one-sided aspherical lens 101 is small, and how much a measurement error generated when performing eccentricity measurement causes an error in the analysis result. Will be described by comparing a conventional example with the present invention. In the figure, each symbol represents the next position. △: Center of curvature of paraxial (center) of aspheric surface 103 □: Center of curvature of aspheric surface 103 ◇: Apex (navel) of aspheric surface 103 ○: Center of curvature of spherical surface 105 ◎: Center of lens outer diameter , Symbol r _A represents the paraxial radius of curvature of the aspheric surface 103, r _S represents the radius of curvature of the spherical surface 105, and Δ represents the amount of aspheric surface (the distance from the center of the paraxial curvature of the aspheric surface to the center of the peripheral curvature).

[0041] In conventional eccentric measuring apparatus shown in FIG. 9, by contacting the spherical 105 to the end surface of the lens support 111, for measuring the deflection of (a straight line passing through the △ and □ and) non-spherical axis with respect to the rotation axis Z ₀ . In this illustrated state, the center of the lens outline ◎ is assumed to be positioned on the rotation axis Z _0.
Here, if the paraxial curvature center △ is erroneously recognized at the position △ ′, the relative deviation δ between the erroneously recognized center of curvature △ ′ and the peripheral curvature center □ is a measurement error. At this time, if the vertex of the aspheric surface erroneously estimated by the analysis is 解析 ′, the distance ΔD from the rotation axis Z ₀ to ₀ ′ is the decenter error amount in this case. An approximate amount of the decenter error amount ΔD is obtained by analysis according to the following equation. ΔD ≒ ｛(r _A + Δ) / Δ｝ × δ Here, since {(r _A + Δ) / Δ｝> 1, the decenter error amount ΔD with respect to the rotation axis Z ₀ obtained by this analysis is obtained.
Means that the measurement error δ is enlarged by about ｛(r _A + Δ) / Δ｝.

On the other hand, according to the present invention, the peripheral portion of the aspherical surface 103 is brought into contact with the end surface of the lens support 15 to be rotated, and the aspherical position is adjusted with respect to the rotation axis Z ₀ through the aspherical position adjustment described above. The deflection of the paraxial center of curvature or the vertex of the spherical surface is set to zero. That is, in the present embodiment, the vibration is driven to “0” while directly observing the paraxial curvature center △ of the aspheric surface or the vertex 非 of the aspheric surface.
Is almost equal to the positioning error δ of the aspherical surface. Therefore, even when the amount of aspherical surface is small, highly accurate eccentricity measurement can be performed. In the case of double-sided aspherical surface, by matching the rotation axis Z ₀ aspheric axis towards the aspherical surface amount is small, it is advantageous in the sense that the measurement error can be further reduced.

As described above, the first to fourth embodiments are:
Eccentricity measurement is possible for both single-sided aspherical lenses and double-sided aspherical lenses. Further, in the case of a single-sided aspherical lens, the aspherical surface is supported in contact with the lens contacting edge portion 16 of the lens support 15 to be inspected, and even when the amount of the aspherical surface is small, the aspherical axis is aligned with the rotation axis. By doing so, highly accurate measurement becomes possible. The surface on the opposite side that does not contact the lens support to be measured is measured by any eccentricity measuring means.

[0044]

As is clear from the above description, the present invention
The eccentricity measuring device for spherical lenses can easily measure eccentricity on both surfaces, regardless of whether it is an aspherical surface on one side or an aspherical surface on both sides.
Moreover, according to the present invention, since the aspherical axis can be aligned with the rotation axis, accurate eccentricity measurement of the aspherical surface can be performed. further,
The centering device for an aspherical lens of the present invention accurately aligns the aspherical axis of the test aspherical lens with respect to the rotation axis , and
After the eccentricity of the surface is accurately measured , the lens outer peripheral processing means for processing the outer circumference of the aspherical lens to be tested into a shape determined with respect to the rotation axis is provided. It can be formed (centered) accurately.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a main part of an embodiment of an aspherical lens eccentricity measuring apparatus to which the present invention is applied.

FIG. 2 is an optical path diagram showing a main part of another embodiment of the aspherical position detecting means of the present invention.

FIG. 3 is an optical path diagram showing a main part of still another embodiment of the aspherical surface position detecting means of the present invention.

FIG. 4 is a block diagram showing another embodiment of the eccentricity detecting means of the present invention.

FIG. 5 is a block diagram showing a main part of an embodiment of an aspherical lens centering device to which the present invention is applied.

FIG. 6 is a plan view illustrating a state where an aspheric lens is centered in a circular shape by the centering device of the present invention.

FIG. 7 is a plan view illustrating a state where an aspheric lens is centered in a square shape by the centering device of the present invention.

FIG. 8 is a diagram illustrating a state of an ideal single-sided aspherical lens.

FIG. 9 is a diagram illustrating a state when eccentricity measurement of a single-sided aspherical lens is performed by a conventional measuring unit.

FIG. 10 is a diagram illustrating a state in which eccentricity measurement of a single-sided aspheric lens is performed by the apparatus of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Lens support rotation block 13 Turntable (rotation means) 15 Test lens support (Aspheric lens support means) 16 Lens contact edge 21 Test aspheric lens 22 Aspheric surface 23 Aspheric surface 30 Eccentricity measurement block (Aspheric surface) Position detecting means, eccentricity detecting means 31 laser light source 37 point light source (index) 51 video camera 53 monitor television 57 electric pick sensor (eccentricity detecting means) 60 lens position adjusting block 61 electric micrometer (aspherical lens position adjusting means) ) 70 control block 71 computer

Continuation of the front page (56) References JP-A-4-190130 (JP, A) JP-A-1-296132 (JP, A) JP-A-61-144541 (JP, A) JP-A-5-312670 (JP) JP-A-5-177526 (JP, A) JP-A-4-268433 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G01M 11/00-11/08

Claims (5)

(57) [Claims] A rotating means for creating a rotation axis serving as a reference for measurement; and a rotating means for rotating the aspherical lens under test while supporting the aspherical lens while contacting the periphery of the aspherical surface of the aspherical lens. Aspherical lens support means , along the rotation axis on the aspherical surface or the opposite surface
Alternatively, an optical target image is projected, and the aspherical surface or
Based on the reflection image reflected from the opposite surface, the rotation
Displacement of the center of the aspheric surface with respect to the axis and
Detecting eccentricity of the surface opposite to the spherical surface with respect to the rotation axis
Detecting means, and an aspheric lens position adjusting means for moving and adjusting the test aspheric lens in a direction substantially perpendicular to the rotation axis according to a detection value of the detecting means. Aspherical lens eccentricity measuring device. 2. An eccentricity measurement of the aspherical lens according to claim 1.
In the apparatus, the detecting means focuses the laser beam.
A laser light source using the point light source as the index image, and the index image
Are irradiated along the rotation axis, the aspheric surface and
Optical path switching means for selecting from a surface facing the aspheric surface;
Receives a point light source reflected on the aspheric surface or the opposite surface
An aspherical lens eccentricity measuring device provided with an image pickup means. 3. An aspheric lens according to claim 1, wherein
In the eccentricity measuring device, the aspheric surface is detected by the detecting means.
Paraxial aspherical surface of the aspherical surface while detecting misalignment of the central portion of the aspherical surface.
The aspheric lens so that a plane axis coincides with the rotation axis
After adjustment by the position adjustment means, the detection means
Eccentricity measurement of an aspherical lens for detecting eccentricity of the opposite surface
Setting device. 4. The non-volatile memory according to claim 1, wherein
The eccentricity measuring device for an aspherical lens further comprises an outer-peripheral-vibration detecting means for detecting a vibration of an outer peripheral portion of the aspherical lens to be measured with respect to the rotation axis. 5. An apparatus for measuring eccentricity of an aspherical lens according to claim 1, wherein the outer periphery of the aspherical lens to be tested is processed into a shape determined with respect to the rotation axis. A centering device for an aspherical lens, comprising: processing means.