JPS61144541A - Optical component eccentricity measuring device - Google Patents

Abstract

PURPOSE:To measure efficiently an eccentric quantity, etc. of a lens without touching them by providing a laser interference device and a sample placing base which can be displaced, and moving the sample placing base so that the center axis of an object to be measured and the optical axis of the laser interference device coincide with each other. CONSTITUTION:An eccentricity measuring device is constituted of a laser interference device 1 having a reference lens 4, sample placing base 10 consisting of a rotary base 10a which can turn around a Z axis, Y moving base 10b and an X moving base 10c, displacement measuring instrument 7 having a contact 7b, X moving measuring instrument 13x, Y moving extent measuring instrument and converged light display devices 5a, 5b, etc. In such a state, an object to be measured 8 having an aspherical lens surface 9 is placed on the rotary base 10a, the contact 7b is made to contact to its side face, and thereafter, the center axis of the object to be measured 8 and the optical axis of the interference device 1 are made to coincide with each other, and an eccentric quantity is measured by a moving extent of the placing plate 10 of the time when a reflected image of a laser beam reflected on the display devices 5a, 5b has coincided with the center of the display devices 5a, 5b.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to an eccentricity measuring device for optical components, and in particular, to measuring the eccentricity of a lens surface, that is, the deviation between the optical axis and the central axis of the lens on the lens surface. The present invention relates to an optical component eccentricity measuring device suitable for measuring the angle of inclination between the optical axis and the central axis.

[Background of the invention]

The conventional method for measuring lens eccentricity is disclosed in Japanese Patent Application Laid-open No. 48-595.
As described in Publication No. 6, 1
It was used to measure the eccentricity of a lens or lens system. In this way, since transmitted light is used, it is not possible to measure the eccentricity and deflection of one side of a single lens or, for example, the lens molding surface of a mold used for molding plastic lenses.・I couldn't come.

There is a three-dimensional measuring device as a measurement device that does not use transmitted light, but since the measurement with this three-dimensional measuring device is a contact method, there is not only a risk of damaging the lens surface with the stylus. There was also the problem that measurement took a long time and measurement efficiency was poor.

[Purpose of the invention]

The present invention improves the problems of the prior art described above and provides an optical component eccentricity measuring device that can efficiently measure the eccentricity and deflection of one side of a lens in a non-contact manner. This is the purpose.

[Summary of the invention]

The configuration of the eccentricity measurement device for optical components according to the present invention includes a laser interference device that has optical axes in two directions and is movable in these directions, and a laser interference device that is rotatable around two axes and moves in the X and Y directions. A sample mounting table that can be tilted in the XZ plane and Y2 plane, on which the object to be measured can be placed and fixed, and the amount of movement of this sample mounting table in the X and Y directions can be measured. a movable thickness measuring device, a tilting knob capable of tilting the sample mounting table in the XZ plane and the YZ plane and displaying the amount of tilt;
a displacement measuring device that is provided integrally with the laser interference device and is capable of measuring the displacement in the X direction of the object to be measured that is placed and fixed on the sample mounting stage; The reflected image of the convergent laser beam converging on the surface of
The present invention is equipped with a display device capable of displaying the outer peripheral line of interference fringes.

[Embodiments of the invention]

Before entering into the description of the embodiments, basic matters related to the present invention will be explained.

In order to make it possible to measure the lens molding surface of a mold or one side of a lens, which cannot be measured with transmitted light, the optical component eccentricity measuring device of the present invention uses a laser interference device to measure the lens molding surface of the object to be measured. A display device captures the reflected image of the laser beam irradiated onto the surface. The sample mounting table on which the object to be measured is placed is configured to be rotatable around the optical axis of the laser interference device, movable in a plane perpendicular to the optical axis, and tiltable out of the plane. did. Further, a displacement measuring device capable of measuring the displacement of the object to be measured is provided integrally with the laser interference device.

With this configuration, when the displacement measuring device that is in contact with the side surface of the object to be measured is moved in the vertical direction along the optical axis direction of the laser interference device, the amount of displacement hardly changes. Then, correct the inclination of the sample mounting stage. Thereby, the central axis of the object to be measured and the optical axis of the laser interference device become parallel. Next, when the sample mounting table is rotated, the sample mounting table is moved within its plane so that a change in the scale of the displacement measuring device is minimized. Thereby, the central axis of the object to be measured and the optical axis of the laser interference device are aligned.

When the sample mounting stage is moved so that the reflected image reflected on the display device coincides with the center position of the display device, the amount of movement is the amount of eccentricity, and the interference fringe near the center of the reflected image is The angle of inclination when the sample mounting stage is tilted so that it becomes a concentric circle is the angle of inclination.

The present invention has been made based on the above-mentioned basic matters.

Examples will be described below.

FIG. 1 is a side view of an optical component eccentricity measuring device according to an embodiment of the present invention, FIG. 2 is a plan view of the optical component eccentricity measuring device according to FIG. 1, and FIG. 1 is a partial side view showing the laser beam from the laser interference device and its reflection state, FIG. 4 is a partial side view showing the positional relationship between the central axis of the object to be measured and the optical axis in FIG. The figure is a partial side view showing the relationship between the central axis, optical axis, and sag of another object to be measured (aspherical surface).

In the figure, 1 stands for 2 directions (vertical direction in Figure 1)
This laser interference device is equipped with a reference lens 4 for converging laser light, and has an optical axis at
It is attached to a support rod 3 erected at 4 so as to be movable in two directions. 10 is a support frame 1 mounted on the support stand 14.
The sample mounting table 10 is supported by a rotary table 10α that is rotatable around two axes;
It is equipped with an X-movement table 10b and an X-movement table 10e, and the object to be measured 8 can be placed and fixed on the rotary table 10α. Reference numeral 11 denotes a motor attached to the sample mounting table 10, which is used to rotate the rotary table 10α, and 12x is used to move the sample mounting table 10 in the X direction. The X-movement knob 12y attached to the X-movement table 10C is an X-movement knob attached to the X-movement table 10b, which is used to move the sample mounting table 10 in the Y direction. 19. f is an XZ plane tilt knob that can tilt the sample mounting table 10 in the XZ plane and display the amount of tilt; 19y is the sample mounting table 10;
This is a YZ plane tilting knob that can tilt in the XZ plane and display the amount of tilt. 7 is
A displacement measuring instrument having a probe 7b capable of measuring the displacement in the X direction of an object to be measured 8 mounted and fixed on a sample mounting stage 10, and this displacement measuring instrument 7 is connected to the laser interference device 1. It is integrally attached to the laser interference device 1 by a support bar 6 attached to the laser interference device 1. 13x, 1sy are
Both are placed on a support stand 14, and each sample mounting stand 1
X that can measure the amount of movement of 0 in the X and Y directions
These are a movement amount measuring device and an X movement amount measuring device.

16 is a convergent laser beam emitted from the laser interference device 1 and converged on the lens surface 9 on the surface of the object to be measured 8;
α, 5b are the reflected images 17. of this convergent laser beam 16, respectively. This is a convergent light display device and an interference fringe display device that can display the outer circumference 41i18 of interference fringes.

The operation of the eccentricity measuring device for optical components configured in this way is as follows.
First, the case of the object to be measured 8 in which the lens surface 9 is a spherical surface will be described.

The object to be measured 8 is mounted and fixed on the rotary table 10α of the sample mounting table 10. Adjust the support arm 2 and the displacement measuring device arm 7α to bring the contactor 7b of the displacement measuring device 7 into contact with the side surface of the object to be measured 8.@Move the supporting arm 2 up and down along the support plate 3. When 1
Adjust the surface inclination knob 19/ to correct the inclination of the sample mounting stage 10. Thereby, the central axis of the object to be measured 8 and the optical axis of the laser interference device 1 become parallel.

When the rotary table 10cL is rotated by driving the motor 11, the X movement is performed so that the displacement display of the displacement measuring device 7 becomes a predetermined value (a preset external shape error of the object 8, for example, 2 μm). Knobs 12x.

Adjust the X movement knob 1231. As a result, the central axis of the object to be measured 8 and the optical axis of the laser interference device 1 are aligned.

The laser interference device 1 is turned ON, the reference lens 4 is adjusted, and the laser beam from the laser interference device 1 is converged on the lens surface 9 (Fig. The reflected image is displayed on the convergent light display device @5a and the interference fringe display device 5b.The reflected image 17 of this convergent laser beam is displayed on the display device 5a as shown in FIG.
It is shifted from the center position 15g.

By the way, since the lens surface 9 of the object to be measured 8 is a spherical surface,
As shown in FIG. 4, the optical axis 20 passes through the highest position of the lens surface 9 and is parallel to the central axis 21, and there is no "sagging".
Since it is the image at the highest position, the amount of deviation between the center position 15L of the convergent light display device 5a and the reflected image 17 in FIG. 3 is the eccentricity amount 22 shown in FIG.

Therefore, the X movement knob 12&,
By operating the movement knob 12y, the X movement amount measuring device 13 &, X movement amount measuring device 1! By inputting the measured amount of By to a microcomputer (not shown), a desired eccentricity amount 22 is calculated.

Next, the object to be measured 8A (fifth lens) whose lens surface is aspherical
The case shown in Figure) will be explained.

The operation of aligning the central axes 21A of the eight objects to be measured with the optical axis of the laser interference device 1 is the same as in the case of the object to be measured 8 (the lens surface 9 is spherical) described above. Further, by operating the laser interference device 1, the reflected image 17 of the convergent laser beam is displayed on the convergent light display device 5α and the interference fringe display device 5h. The method for displaying interference fringes is also similar.

By the way, since the lens surface 9A of the object to be measured 8A is an aspherical surface, there is only one optical axis 20A, and unlike the case of a spherical surface, the optical axis 2OA is located between the eccentricity j122A and the 23. exist. Therefore, the XZ plane tilt knob 192
and YZ plane inclination knob 15'3/ to reduce the sag.

As the sagging decreases, the reflected image 17 of the object to be measured 8A rotated by the motor 11.The movement of the outer periphery of the interference fringes @18 becomes smaller, and it comes to rest when the sagging disappears.The XZ plane inclination at this time By inputting the amount of inclination displayed on the knob 19! and the YZ plane inclination knob 193T to the microcomputer, the desired "sag, 23" is calculated. X movement mamami 12x.

Operate the X movement knob 12y to move the sample mounting stage 1°, and reflect the reflected image 17. The centers of the interference fringe concentric circles 18 are made to coincide with the display device centers 15α and 15b, respectively. X movement amount measuring device 135 at that time. By inputting the measured amount of the X movement amount measuring device 13y to the microcomputer, the desired eccentricity amount 22A is calculated.

To give specific figures, the allowable amount of eccentricity is usually 10 μm.
By using the device of this embodiment, α3
Measurement can be performed in units of μm/interference fringe. .

According to the embodiments described above, the amount of eccentricity of the lens molding surface of the mold or one side of the lens, which was impossible to measure using conventional transmitted light.

In addition, the measurement of pores has become possible by using laser light. At the same time, the use of laser light enables non-contact measurement, and unlike contact-type measurements such as those using coordinate measuring machines, the entire lens surface can be measured at once, significantly shortening the measurement time. It also has the effect of preventing surface damage caused by contact with the stylus, as in the case of a contact type.

In addition, since the outer shape of the object to be measured can be made parallel or coincident with the optical axis of the laser interference device 1, the outer shape of the object to be measured can be
It becomes possible to measure the amount of eccentricity and tilt of the lens surface relative to the outer shape, and it is possible to accurately indicate the content and amount to be corrected when correcting the eccentricity of the lens molding surface of the mold.

In addition, since it is possible to separate the amount of eccentricity and waviness of the lens surface, which were not captured separately in the conventional measurement methods, it is also effective when correcting the eccentricity of the lens molding surface of a mold.

In this embodiment, only one displacement measuring device 7 is provided, but a plurality of displacement measuring devices 7 are attached to the support par 6 in two directions (upward and downward directions).

If the central axis of the object to be measured 8 and the optical axis of the laser interference device 1 are parallel to each other, there is no need to move the support arm 2 up and down, which improves measurement efficiency. It has the advantage of increasing the meat even further.

〔Effect of the invention〕

As described in detail above, according to the present invention, it is possible to provide an optical component eccentricity measuring device that can efficiently measure the eccentricity and deflection of one side of a lens in a non-contact manner. .

[Brief explanation of the drawing]

FIG. 1 is a side view of an optical component eccentricity measuring device according to an embodiment of the present invention, FIG. 2 is a plan view of the optical component eccentricity measuring device according to FIG. 1, and FIG. 1 is a partial side view showing the laser beam from the laser interference device and its reflection state; FIG. 4 is a partial side view showing the positional relationship between the central axis of the object to be measured and the optical axis in FIG. 1; The figure is a partial side view showing the relationship between the central axis, optical axis, and sag of another object to be measured (aspherical surface). 1... Laser interference device, 5α... Convergent light display device,
5b... Interference fringe display device, 7... Displacement measuring device, 8° 8A... Measured object, 10... Sample mounting stand, 10α.
...times, private money, 1ab-...X moving table 51QC-X moving table, 11...motor, 12x...X moving knob, 1
2y...X movement knob, 15. f--X movement amount measuring device, 13y...
XZ plane inclined knob, 19y...XZ plane inclined knob, 2
2, 22A... Eccentricity, 23... Fall. Representative Patent Attorney Akira Takahashi Unemployment 1 Figure Mei 2 Figure

Claims (1)

[Claims] 1. A laser interference device that has an optical axis in the Z direction and is movable in this direction, and a laser interference device that is rotatable around the Z axis and movable in the X and Y directions, and that is movable in the XZ plane. , a sample mounting table capable of tilting in the YZ plane and capable of mounting and fixing an object to be measured, and a movement amount measuring device capable of measuring the amount of movement of this sample mounting table in the X direction and the Y direction; A tilt knob that can tilt the sample mounting table in the XZ plane and YZ plane and display the amount of inclination, and an X
a displacement measuring device that is integrated with the laser interference device and is capable of measuring displacement in a direction; a reflected image of a convergent laser beam emitted from the laser interference device and converged on the surface of the object to be measured; and an outer periphery of interference fringes. 1. A device for measuring eccentricity of an optical component, comprising: a display device capable of displaying a line. 2. The eccentricity measuring device for an optical component according to claim 1, wherein a plurality of displacement measuring devices are provided in the Z direction.