JPH0783627A - Dimension-measurement apparatus - Google Patents

Abstract

PURPOSE:To execute the accurate measurement by a method wherein a means that condenses a light on a two-dimensional sensor is provided so as to vary a ratio between a deviation in a direction perpendicular to a light scanning direction and that in the light scanning direction on a light-casting position on the surface of an object to be inspected. CONSTITUTION:Light from a light source 41 is converted into a small spot light by a condenser lens 42 to be cast on an oscillating mirror 43 that is oscillated by a motor 44. A condenser lens 55 changes a passage of the spot light 45 so that the spot light is vertically cast on the surface of an object 46 to be inspected and to be reciprocally scanned on the object straight in a Y axis direction from the upper section thereof. The spot light 45 is reflected at the light casting position 47 on the object 46 to become a reflection light 48. The reflection light 48 wherein ratio between a component in a direction of an X axis and a component in the direction of the Y axis that is enough longer than that in the X axis direction is varied, is condensed on a two-dimensional sensor 49. An output of the sensor 49 is inputted to a data processing device 54. The device 54 calculates coordinates of the spot light in the directions of the X axis and Y axis on the basis of the data from the sensor 49.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dimension measuring device for measuring unevenness on a surface by utilizing light reflection.

[0002]

2. Description of the Related Art Conventionally, as this type of dimension measuring device,
For example, an apparatus disclosed in Japanese Patent Laid-Open No. 58-148904 is known. This will be described with reference to FIG. 4. Reference numeral 1 is a light source, 2 is a condenser lens, and 3 is an oscillating mirror attached to a rotation shaft of a motor 4, and the projector 1 is constituted by these.
2 is disposed obliquely above the inspection object 6. Reference numeral 5 is a spot light, 6 is an inspection object, and 7 is a light irradiation position on the inspection object 6. 9 is a one-dimensional sensor, 11 is a cylindrical lens, and these constitute the light receiver 13. Further, the motor control circuit 15 that controls the motor 4 and the one-dimensional sensor 9 are connected to the data processing circuit 14.

The conventional dimension measuring device configured as described above operates as follows. The light from the light source 1 is converted into a small spot light by the condenser lens 2 and applied to the oscillating mirror 3, and the oscillating mirror 3 is oscillated by the motor 4, so that the spot light 5 is obliquely above the object 6 to be inspected. Reciprocally scan linearly. The spot light 5 is reflected at the light irradiation position 7 on the inspection object 6 and focused on the one-dimensional sensor 9 by the cylindrical lens 11. This cylindrical lens 11
Thus, the displacement of the spot light 5 in the scanning direction is eliminated, and only the displacement in the direction perpendicular to the scanning method is condensed on the one-dimensional sensor 9. The one-dimensional sensor 9 collects the light condensed in a straight line by the cylindrical lens 11. Receive light. One-dimensional sensor 9
Is a plurality of light receiving elements arranged in a straight line in a column. The output signal from the motor control circuit 15 and the corresponding output signal from the one-dimensional sensor 9 are input to the data processing circuit 14. In this case, the X-direction coordinates can be calculated from the output signal from the motor control circuit 15, and the Y- and Z-direction coordinates can be calculated from the output signal of the one-dimensional sensor 9 corresponding to the output signal. Therefore, the data processing circuit 14 receives the data continuously input from the motor drive circuit 15 and the one-dimensional sensor 9 in response to the scanning of the spot light 5.
The shape and size of the inspection object 6 can be obtained by calculating

[0004]

Next, the problems of the above-mentioned conventional device will be described with reference to FIGS. In the above-mentioned conventional technique, the cylindrical lens 11 is used as a lens for condensing the reflected light. However, in order to make the condensing state easy to understand, the toric lens 1 which is a superordinate concept thereof is used here.
6 will be used. 5 is a view seen from the Y-axis direction of the toric lens 16, and FIG. 6 is a view seen from the X-axis direction. Here, 7a indicates the light irradiation position of the spot light 5 on the lower surface of the inspection object 6, and 7b indicates the light irradiation position on the upper surface of the inspection object 6. Then, the light irradiation positions 7a and 7b
The X-axis direction component and the Y-axis direction component of the distance to and are defined as L2 and L2, respectively. In addition, the light irradiation position 7a on the one-dimensional sensor 9
The X-axis direction component and the Y-axis direction component of the distance between the focal point position and the focal point position of the light irradiation position 7b are set to 11 and 12 respectively. As shown in FIG. 7, the Z axis is in the optical axis direction of the toric lens 16,
The X-axis is defined such that the surface with a small radius of curvature is on the XZ plane, and the Y-axis is such that the surface with a large radius of curvature is on the YZ plane. FIG. 8 is an enlarged view of the light irradiation position of FIG. 6, and a broken line 17 is a scattered light beam reflected from the light irradiation position and shows the intensity and direction of the scattered light beam in a vector manner.
8A shows the case where the angle formed by the spot light 5 and the inspection object 6 is large, and FIG. 8B shows the case where the angle formed by the spot light 5 and the inspection object 6 is small. The case is shown.

Here, assuming that the magnifications shown in FIGS. 5 and 6 are β1 and β2, respectively, β1 = − (l1 / L1) β2 = − (l2 / L2), and the ratio β1: β2 of these magnifications is If L1 = L2, then β1: β2 = 11: 12. When a one-dimensional sensor is used, this ratio must be made very large, but there is a problem that it is difficult to realize with a simple optical system.

Further, as shown in FIGS. 6 and 8, L2
If the angle formed by the spot light 5 and the object 6 to be inspected is increased in order to increase, the amount of light incident on the one-dimensional sensor 13 decreases, and the S / N ratio deteriorates. Further, since the positions in the Y-axis direction of the lower irradiation position 7a and the upper irradiation position 7b of the inspection object 6 are largely different, there is a problem that accurate measurement is difficult.

The present invention has been made in view of the above problems, and by using a two-dimensional sensor, the ratio l of the magnification is
It is an object of the present invention to provide a dimension measuring device capable of making 1:12 into a practical size with a simple optical system.

[0008]

In order to achieve the above object, in the dimension measuring apparatus of the present invention, the surface of the object to be inspected having a reflecting surface is irradiated with light, and spot light is applied to the surface of the object to be inspected from above. Dimension measurement in which an optical scanning means for linearly scanning is provided, the reflected light from the surface of the object to be inspected is received, photoelectrically converted, and the signal is input to calculate the shape and dimension of the object to be inspected by a data processing device. In the apparatus, a two-dimensional sensor is arranged above the object to be inspected, and reflected light on the surface of the object to be inspected is directed in a direction perpendicular to the optical scanning direction of the light irradiation position of the spot light on the surface of the object to be inspected. A means for condensing light onto the two-dimensional sensor is provided so that the ratio between the deviation and the deviation in the scanning direction can be changed.

To explain this structure more specifically with reference to FIG. 1, the projector 32 is mounted on the light source 21, a condenser lens 22 for condensing light from the light source 21, a motor 24, and the axis of the motor 24. And an oscillating mirror 23. Two
Reference numeral 5 is a spot light, and the light irradiation position 27 of the spot light 25 is on the inspection object 26. The light receiver 33 includes the condenser lens 3
0, toric lens lens 31, and two-dimensional sensor 29
And receives the reflected light 28. Two-dimensional sensor 29
Is connected to the data processing device 34. Here, the XYZ axes are determined so that the inspection object 26 is fixed on the XY plane.

[0010]

The size measuring apparatus of the present invention having the above-described structure operates as follows. Condensing lens 22 for collecting light from light source 21
To irradiate the oscillating mirror 23 into a small spot light, and the oscillating mirror 23 is oscillated by the motor 24, so that the spot light 25 is linearly reciprocally scanned on the inspection object 26 from above in the Y-axis direction. The spot light 25 is reflected at the light irradiation position 27 on the inspection object 26 and becomes reflected light 28. The reflected light 28 is condensed by the condenser lens 30, and the toric lens 31 further collects the Y-axis direction component of the reflected light 28. That is, the toric lens 31 reduces the deviation of the light irradiation position 27 of the spot light 25 on the surface of the inspection object 26 in the Y-axis direction and focuses the reflected light on the surface of the inspection object 26 on the two-dimensional sensor 29. Fulfill. In other words, this toric lens 31 causes the reflected light 28
Changes the ratio between the X-axis direction component of the light irradiation position 27 and the Y-axis direction component that is sufficiently long, and the two-dimensional sensor 29
Focused on top. The output of the two-dimensional sensor 29 is input to the data processing device 34. The data processor 34 can calculate the coordinates of the spot light 25 in the Y-axis direction and the coordinates of the Z-axis direction based on the data from the two-dimensional sensor 29. Therefore,
By processing the data continuously sent from the two-dimensional sensor 29 with the data processing device 34, the shape of the inspection object 26 can be measured. Here, if a cylindrical lens is used instead of the toric lens 31 used for changing the ratio of the X-axis direction component and the Y-axis direction component on the sensor to collect the light, the cylindrical lens is used. Since the component cannot be condensed, if the X-axis direction component is condensed by the condenser lens 30 and the ratio of the X-axis direction component and the Y-axis direction component is changed in the entire light-receiving optical system, it can be condensed on the two-dimensional sensor 29. It will be good.

[0011]

Embodiment 1 An embodiment of the dimension measuring apparatus according to the present invention will be described below with reference to the accompanying drawings. FIG. 2 is a diagram illustrating the dimension measuring apparatus according to the first embodiment. As shown in the figure, in this device, the light projector 52 includes a light source 41, a condenser lens 42 for condensing light from the light source 41, a motor 44, a swing mirror 43 mounted on the shaft of the motor 44, and a swing mirror 43. The mirror 43 and the condensing lens 55 on the inspected object 46 side. 45 is a spot light, and a light irradiation position 47 of the spot light 45 is located on the inspection object 46. The light receiver 53 includes a condenser lens 50 and a cylindrical lens 51 which is a kind of toric lens.
The two-dimensional sensor 49 receives the reflected light 48. The two-dimensional sensor 49 is connected to the data processing device 54. Here, the XYZ axes are determined so that the inspection object 46 is fixed on the XY plane.

Next, the operation of the dimension measuring apparatus of this embodiment will be described. The light from the light source 41 is made into a small spot light by the condensing lens 42 and is irradiated on the oscillating mirror 43.
4, the swing mirror 43 is swung. Condensing lens 55
Thus, the optical path is changed so that the spot light 45 vertically strikes the surface of the inspection object 46, and the inspection object 46 is linearly reciprocally scanned in the Y-axis direction from above. This spot light 45 is reflected at the light irradiation position 47 on the inspection object 46 and reflected light 4
It becomes 8. The reflected light 48 is collected by the condenser lens 50, and the cylindrical lens 51 further collects the Y-axis direction component of the reflected light 48. That is, the cylindrical lens 51 reduces the deviation of the light irradiation position 47 of the spot light 45 on the surface of the inspection object 46 in the Y-axis direction to reduce the inspection object 46.
The light reflected on the surface is condensed on the two-dimensional sensor 49. In other words, the cylindrical lens 51 changes the ratio of the X-axis direction component of the light irradiation position 47 to the Y-axis direction component that is sufficiently long, and collects the reflected light 48 on the two-dimensional sensor 49. . Two-dimensional sensor 4
The output of 9 is input to the data processing device 54. The data processing device 54 can calculate the coordinates of the spot light 45 in the Y-axis direction and the coordinates of the Z-axis direction based on the data from the two-dimensional sensor 49. Therefore, by processing the data continuously sent from the two-dimensional sensor 49 by the data processing device 54, the shape of the inspection object 46 can be measured.

According to this embodiment, since the spot light is emitted from the vertical direction of the surface of the inspection object, a smaller spot light can be emitted onto the inspection object and the resolution in the scanning direction is improved.

[0014]

Second Embodiment Next, a dimension measuring device according to a second embodiment will be described. FIG. 3 is a diagram illustrating a dimension measuring device according to the second embodiment. As shown in the figure, in this device, the projector 72 includes a light source 61, a condenser lens 62 for condensing light from the light source 61, a motor 64, and a swing mirror 63 mounted on the shaft of the motor 64.
Composed of and. A motor control circuit 75 drives and controls the swing mirror driving motor 64. 65 is a spot light,
The light irradiation position 67 of the spot light 65 is on the inspection object 66. The light receiver 73 includes a condenser lens 70, a cylindrical lens 71 which is a kind of toric lens, and a two-dimensional sensor 69, and receives the reflected light 68. The two-dimensional sensor 69 and the motor control circuit 75 are the data processing device 74.
It is connected to the. Here, the XYZ axes are determined so that the inspection object 66 is fixed on the XY plane.

Next, the operation of the dimension measuring apparatus of this embodiment will be described. The light from the light source 61 is made into a small spot light by the condensing lens 62, which is applied to the swing mirror 63, and the motor 6
The rocking mirror 63 is rocked by 4 and the spot light 65
Is linearly reciprocally scanned on the inspection object 66 from above in the Y-axis direction. The spot light 65 is reflected at the light irradiation position 67 on the inspection object 66 to be reflected light 68. Reflected light 68
Is condensed by the condenser lens 70, and the cylindrical lens 7
1 further collects the Y-axis direction component of the reflected light 68.
That is, the cylindrical lens 71 causes the spot light 6
5, the deviation of the light irradiation position 67 on the surface of the inspection object 66 in the Y-axis direction is reduced, and the light reflected on the surface of the inspection object 66 is focused on the two-dimensional sensor 69. In other words,
With this cylindrical lens 71, the reflected light 68 is
The ratio of the X-axis direction component of the light irradiation position 67 and the Y-axis direction component that is sufficiently long is changed, and the light is focused on the two-dimensional sensor 69. The output of the two-dimensional sensor 69 is input to the data processing device 74. The data processing device 74 calculates the coordinates in the Z-axis direction from the data from the two-dimensional sensor 69, and calculates the coordinates in the Y-axis direction from the output signal from the motor control circuit 75. Therefore, the shape of the inspection object 66 can be measured by fetching the data of the two-dimensional sensor 69 in synchronization with the data sent from the motor control circuit 75 and processing it by the data processing device 74.

According to the present embodiment, since only one-dimensional data needs to be fetched from the two-dimensional sensor and processed, the shape measurement can be performed at high speed.

[0017]

As described above, according to the dimension measuring apparatus of the present invention, the two-dimensional sensor is arranged above the object to be inspected,
A two-dimensional sensor that can change the ratio of the deviation of the reflected light from the surface of the inspection object in the direction perpendicular to the optical scanning direction of the light irradiation position of the spot light on the surface of the inspection object to the scanning direction. Since the means for collecting light upward is provided, it is possible to accurately measure a minute height of a large inspection object.

[Brief description of drawings]

FIG. 1 is a diagram illustrating a configuration of a dimension measuring device according to the present invention.

FIG. 2 is a diagram showing a dimension measuring apparatus according to a first embodiment of the present invention.

FIG. 3 is a diagram showing a dimension measuring apparatus according to a second embodiment of the present invention.

FIG. 4 is a diagram showing a conventional dimension measuring device.

FIG. 5 is a diagram for explaining a problem of the conventional technique.

FIG. 6 is a diagram for explaining a problem of the conventional technique.

FIG. 7 is a diagram for explaining a problem of the conventional technique.

FIG. 8 is a diagram for explaining a problem of the conventional technique.

[Explanation of symbols]

 1, 21, 41, 61 Light source 2, 22, 42, 62 Condensing lens 3, 23, 43, 63 Swing mirror 4, 24, 44, 64 Motor 5, 25, 45, 65 Spot light 6, 26, 46 , 66 Inspected object 7, 27, 47, 67 Light irradiation position 28, 48, 68 Reflected light 9 One-dimensional sensor 29, 49, 69 Two-dimensional sensor 30, 50, 70 Condensing lens 11, 31, 51, 71 Cylindrical Lens 12, 32, 52, 72 Light projector 13, 33, 53, 73 Light receiver 14, 34, 54, 74 Data processing circuit 15, 75 Motor control circuit 55 Condensing lens 16 Toric lens 17 Reflected light

Claims (1)

[Claims] 1. Reflection from the surface of the object to be inspected, which is provided with light scanning means for irradiating the surface of the object to be inspected having a reflecting surface with light, and scanning the spot light linearly from above on the surface of the object to be inspected. In a dimension measuring device that receives light, photoelectrically converts it, inputs the signal, and calculates the shape and dimension of the inspection object by a data processing device, a two-dimensional sensor is arranged above the inspection object, The reflected light on the surface of the inspection object is changed so that the ratio of the deviation of the spot light in the direction perpendicular to the optical scanning direction of the light irradiation position on the surface of the inspection object and the deviation in the scanning direction can be changed. A dimension measuring device comprising means for collecting light onto a dimension sensor.