KR100855849B1 - Position variation measuring apparatus and figure inspecting apparatus using the same - Google Patents

Abstract

An optical sensor having a compound eye function capable of detecting light specularly reflected at different angles in accordance with the shape of a measuring point on an object to be measured provides a technique for measuring displacement of an inclined surface as well as a vertex or a flat surface.

The light transmitting part 100 includes a plurality of light receiving parts 200, 210, and 220 for condensing light to a measuring point on a measurement target and receiving reflected light reflected from the measuring point. The plurality of light receiving parts includes light that is transmitted. And the light receiving ranges arranged in a substantially fan shape with the measuring points as axes in the direction intersecting the plane substantially perpendicular to the object to be measured and receiving from the measuring points occupied by the light receiving surfaces of each light receiving portion are adjacent to each other. It is set as the structure arrange | positioned so that surfaces may continue.

Displacement measurement, compound eye function, shape inspection

Description

Displacement measuring device and shape inspection device using the same {POSITION VARIATION MEASURING APPARATUS AND FIGURE INSPECTING APPARATUS USING THE SAME}

It is a typical block diagram for demonstrating embodiment of the optical displacement sensor which concerns on FIG.

FIG. 2 is a schematic view of the configuration of FIG. 1 seen from an arrow A. FIG.

3 is a view for explaining a light receiving unit including a light receiving element PSD and a light receiving lens (functional element), and for explaining a case in which a plurality of light receiving units are configured in the same configuration.

4 is a diagram for explaining an example of the case where the light receiving lens functional elements of the plurality of light receiving units are replaced.

FIG. 5 is a diagram for explaining an example in which the light receiving lens functional element and the light receiving element PSD in the plurality of light receiving portions are different.

6 is a diagram showing a functional configuration of an embodiment of a displacement measuring device of the present invention.

FIG. 7 is a diagram showing a functional configuration of an embodiment of a shape inspection apparatus using the embodiment of FIG. 6.

8 is a diagram illustrating an example of a displacement measurement result.

9 is a view for explaining the continuity of the light receiving range of the light receiving lens.

10 is a diagram illustrating a configuration example provided with two optical displacement sensors.

11 is a diagram for explaining a position of a camera.

12 is a view for explaining the prior art.

<Description of the symbols for the main parts of the drawings>

1: collimator lens 2: condensing lens

3: light receiving lens (functional element) 4, 4a, 4b: optical displacement sensor

5: syringe port 6: control unit

7, 8: adder 9: calculator

10: image processing unit 11: comparison means

12: judgment means 13: display means

LD: light source PSD: light receiving element

100: light transmitting part 200, 210, 220: light receiving part

300: displacement measurement unit 400: inspection unit

500: camera 600: seal material

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a displacement measuring device for triangulating displacement of the surface of a measurement object by receiving light reflected on the object to be scanned and receiving the reflected light and a shape inspection device using the same. In particular, the present invention relates to a technique capable of measuring the displacement of the surface of an object to be inclined in the scanning direction.

Conventionally, there exist some which were shown by the prior art of patent document 1 as an apparatus which measures displacement by triangulation. When the displacement measurement is performed by such a prior art, there is a problem that the inclination of the surface of the object to be measured cannot be measured well. For example, as shown in Fig. 12 (A), when trying to measure the surface shape of the sealing material of the object to be measured, the dice are specularly reflected when the scanning light is input at the m point (the point in the plane near the top). When the displacement is measured by measuring the reflected light, and it is moved to the position n point (the point of the inclined plane) as it is, and the measurement is made by inputting the scanning light at the same angle as the measurement at the point m, the reflected light reflected by the point n at the point m Reflects in a different direction from the reflected light. That is, when the detector which detects reflected light is arrange | positioned in the position which receives the reflected light of m points, it may happen that it cannot receive the reflected light of n points. Therefore, when the measurement results are plotted along the scanning direction, as shown by the solid line in Fig. 12 (B), in the inclined portion of the seal member, the recessed portion of the seal member (indicated by the dotted line in Fig. 12 (B)) is indented. You can get a waveform. This is because the reflected light reflected by the specular portion cannot be received as described above.

Therefore, invention of patent document 1 rotates the optical displacement sensor itself along the inclined surface of a to-be-measured object, and measures it. The technique which concerns on invention of patent document 1 was comprised by the automatic control so that an optical displacement sensor may rotate so that the output of an optical displacement sensor may become a predetermined value. Therefore, it was possible to follow the measurement to the inclined surface, the plane, etc. of a measuring point.

[Patent Document 1] Japanese Patent Publication No. Pyeongseong 7-69151

According to the technique of Patent Document 1, since the rotation position (angle) of the optical sensor is automatically controlled so that the output of the optical displacement sensor becomes a predetermined value, the control time until the output of the optical displacement sensor is stabilized to a predetermined value. This necessary thing and the control time depend on the shape (flat surface, inclined surface, etc.) at a measuring point, and the displacement measuring apparatus which measures, and scans a measuring point sequentially, may delay the scanning time. There was. Moreover, the structure and control mechanism of a rotation position were also complicated.

An object of the present invention is to prevent the influence of the shape at the measurement point by an optical sensor having a compound eye function capable of detecting light reflected at different angles according to the shape of the measurement point on the measurement object. It provides a technique for measuring while scanning a measuring point (without taking time to rely on a change in shape).

In order to achieve the above object, the invention described in claim 1, the light condensing lens (2) for irradiating the light source (LD) and the position collected by condensing the light emitted from the light source on the measurement object as a measurement point And a light receiving lens (3) for receiving light reflected by the measurement points symmetrically from the object to be measured, and a light receiving element (PSD) for receiving the light collected by the light receiving lens, on the light receiving surface of the light receiving element. A displacement measuring device for detecting a displacement of the measured object at the measuring point by a light receiving position,

A light receiving unit is formed of the light receiving lens and the light receiving element, and a plurality of light receiving units are provided with respect to one of the light sources around the measurement point, and any one of the plurality of light receiving units receives the reflected light.

In the invention according to claim 2, in the invention according to claim 1, the distance between the measuring point and the light receiving lens is almost the same, and the distance between the light receiving lens and the light receiving element is the same. All are made into substantially the same structure.

The invention described in claim 3 includes a light source LD, a condenser lens 2 for irradiating a light-condensed position as a measurement point by condensing the light emitted from the light source on a measurement object, and the measurement object. And a light receiving lens 3 for receiving the specularly reflected light with the measurement points symmetrical, and a light receiving element PSD receiving the light focused by the light receiving lens, wherein the light source, the light collecting lens, the light receiving lens, and the light receiving element are provided. Is moved relative to the object to be measured so that the measuring point scans the object to be measured, and the displacement of detecting the displacement of the object to be measured at the measuring point by the light receiving position on the light receiving surface of the light receiving element. In the measuring device,
At least three or more light-receiving portions formed by the light-receiving lens and the light-receiving element are provided for one of the light sources, and any one of the plurality of light-receiving portions is formed on both sides of the cross section along the scanning direction of the object to be measured. It arrange | positions centering on the said measuring point so that the reflected light reflected by the specular | flexion part Xn-1 (Xn + 1) and any one part of the top part Xn in between can be received.
Invention of Claim 4 has the light transmission part 100 which irradiates the position condensed by condensing light on a to-be-measured object as a measuring point, and the light receiving part 210 for receiving the reflected light which specularly reflects from the said measuring point. An optical displacement sensor, scanning by moving the optical displacement sensor in a direction orthogonal to a plane perpendicular to a plane substantially perpendicular to the measurement unit including the transmitted light, and measuring displacement of the measured object As a displacement measuring device,

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The optical displacement sensor includes a plurality of light receiving parts (200, 210, 220) with respect to the one light transmitting part, and the plurality of light receiving parts are arranged in a direction crossing the plane toward the measuring point, and each of the light receiving parts The light receiving range capable of receiving the specularly reflected reflected light from the measuring points occupied by the light receiving surfaces of the light receiving surfaces is arranged so that the light receiving surfaces adjacent to each other in the light receiving portions are discontinued in displacement measurement.
In the invention according to claim 5, in the invention according to claim 4, the plurality of light receiving parts are arranged at the point intersecting the plane and symmetrically arranged by the same number on both sides of the direction intersecting the plane. do.

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In the invention according to claim 6, in the invention according to claim 4 or 5, the light transmitting portion measures a light collected position by condensing the light source LD and the light emitted from the light source on the measurement object. And a condensing lens 2 for irradiation as

The plurality of light receiving units may include light receiving lens functional elements 3a, 3b, and 3c that receive and reflect light reflected from the measurement point, and light receiving elements PSD1, PSD2, and PSD3 that receive light collected by the light receiving lens functional element. And the light receiving surface of the light receiving portion is a light receiving surface of the light receiving lens functional element.

In the invention according to claim 7, in the invention according to claim 6, the distances from the plurality of light receiving lens functional elements to the condensed position are almost the same, and each of the light receiving lens functional elements is approximately the same distance from the measurement point. The light-emitting surfaces of the light-receiving lens functional elements that are adjacent to each other are arranged to be adjacent to each other.

In the invention according to claim 8, in the invention according to claim 6, each of the light receiving lens functional elements receives collimated light reflected from the measurement point and uses collimator lenses 3a1, 3b1, 3c1 and collimator. Light receiving light collecting lenses 3a1, 3b2, 3c2 for condensing parallel light from the lens to the corresponding light receiving elements;

The light receiving surface of the light receiving portion is a light receiving surface of the collimator lens, and the light receiving ranges of the light receiving surfaces of neighboring collimator lenses occupy the measurement points are arranged so as to be continuous with each other. The ratio of the distance between the measuring point and the collimator lens and the distance between the light condensing lens and the light receiving element is almost the same.

The invention according to claim 10 includes a light transmitting portion 100 for irradiating a collected light position as a measuring point by condensing light on a measurement object, and a light receiving portion 210 for receiving reflected light reflected from the measuring point. Scan by moving the optical displacement sensor relatively in a direction orthogonal to a plane substantially perpendicular to the object under measurement, including an optical displacement sensor and the transmitted light, and output by the output of the optical sensor. A shape inspection apparatus having a displacement measuring unit (300) for measuring displacement and an inspection unit (400) for determining a poor quality of output of the displacement measuring unit,

The optical displacement sensor includes a plurality of light receiving units 200, 210, and 220 with respect to the one light transmitting unit, and the plurality of light receiving units are arranged in a direction crossing the plane toward the measurement point, and each of the light receiving units The light receiving range which can receive the reflected light reflected from the measurement point occupied by the light receiving surface is arranged such that the light receiving surfaces adjacent to each other in the displacement measurement are arranged continuously.

According to the invention of claim 9, the invention of claim 4 or 5, or the invention of claim 11, in the invention of claim 10, the optical displacement sensor is provided in each of different directions in the scanning direction.

On the other hand, if the expression of the said invention is changed, it can be said as follows. That is, a light source, a light condensing lens irradiating the light emitted from the light source on the object to be measured as a measuring point, and a light receiving lens for condensing by receiving light reflected symmetrically with respect to the measuring point as a boundary. An optical displacement sensor having a lens functional element and a light receiving element receiving the light collected by the light receiving lens functional element, wherein the optical displacement sensor is relative to the object to be measured, and is an optical path from the light source to the measurement point; Scanning the measurement point by moving in a direction orthogonal to a plane substantially perpendicular to the object under test, and shifting the measured object at the measurement point by the light receiving position on the light receiving surface of the light receiving element. A displacement measuring device for detecting

The optical displacement sensor has a plurality of light receiving lens functional elements arranged in a substantially fan shape with the measuring point as an axis symmetrically with respect to the plane in a direction crossing the plane, and also measuring points of the respective light receiving lens functional elements. A position where the light receiving ranges with respect to each other are arranged so as to be continuous between adjacent light receiving lens functional elements in displacement measurement, and the plurality of light receiving elements are condensed by each light receiving lens functional element corresponding to the arranged light receiving lens functional elements. Displacement measuring device comprising a configuration disposed in.

Embodiment of the Invention

Embodiment of this invention is described using drawing. BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic block diagram for demonstrating embodiment of the optical displacement sensor which concerns on this invention. FIG. 1 (A) is a view seen from a direction perpendicular to a plane perpendicular to the object under test including light irradiated from the LD (laser diode) serving as the light source. In other words, this is the view seen from the scanning direction. FIG. 2 is a schematic view of the configuration of FIG. 1 seen from an arrow A. FIG. 3 is a view for explaining a light receiving unit including a PSD as a light receiving element and a light receiving lens (functional element), and for explaining a case in which a plurality of light receiving units have the same configuration. 4 is a diagram for explaining an example of the case where the light receiving lens functional elements of the plurality of light receiving units are replaced. 5 is a diagram for explaining an example where the light receiving lens functional element and the light receiving element PSD in the plurality of light receiving portions are different. 6 is a diagram showing a functional configuration of an embodiment of a displacement measuring device of the present invention. FIG. 7: is a figure which shows the functional structure of embodiment of the shape inspection apparatus using embodiment of FIG. 8 is a diagram illustrating an example of a displacement measurement result. 9 is a diagram for explaining the continuity of the light receiving range. 10 is a diagram showing a configuration example provided with two optical displacement sensors. 11 is a diagram for explaining the position of a camera.

[Optical Displacement Sensor]

Here, the light-transmitting part 100 which consists of the light source LD, the collimator lens 1, and the condensing lens 2 in FIG. 1, a light receiving lens (functional element), and a light receiving element (the combination of 1 is 1). The configuration and operation of the optical displacement sensor constituted by three light receiving units 200, 210, and 220 (sometimes referred to as "light receiving units") composed of a light receiving unit will be described.

On the other hand, in the present invention, the expression "light-receiving lens functional element" is used, but since the same function and performance can be achieved with a single lens or a plurality of lenses, the expression is for displaying them all.

1, the light source LD is a laser diode, for example, and produces light. In reality, although it is a bundle of light (beam), it is shown by the simple line in FIG. The collimator lens 1 receives the light from the light source LD, converts it into parallel light, and sends it to the condensing lens 2. The condenser lens 2 condenses the parallel light received from the collimator lens 1 and irradiates the object to be measured. Hereinafter, this irradiated position is called "measurement point."

1 and 2, in this example, the light receiving lens (functional element) has three of the light receiving lenses 3a, 3b, and 3c (typically referred to as "light receiving lens 3"). The light reflected from the measurement point on the measured object is received and condensed on any one of the light receiving elements PSD1 to 3. In this example, the light receiving element has three of PSD1 to 3 as well. Each of the light receiving elements PSD1 to 3 (typically referred to as "light receiving element PSD") has the same configuration as shown in FIG. 1 (B) in this case. The light receiving elements PSD1 to 3 are elements which optically measure displacement and convert them into electrical signals, and may be constituted by a photodiode or a CCD. The light receiving elements PSD1 to 3 have a position on the PSD that receives light in the longitudinal direction of the optical diagram 1 (B), that is, the displacement Lp is the intensity output from both ends thereof, for example, the value of the output A1 and the output B1. Using Lp1 = (A1-B1) / (A1 + B1). Therefore, as shown in Fig. 1, the change in the shape and height of the measuring point is determined by the above formulas at positions A, A, A and B, respectively, at positions P1, P2, and P3 received by the light receiving elements PSD1 to 3, respectively. It is possible to determine the displacements Lp1 to Lp3 (details later).

The light receiving lenses 3a, 3b, and 3c of Figs. 1 and 2 use the same focal lengths. For example, as shown in Fig. 3, the ratio (focal length F2 on the PSD side / focal length F1 on the measurement point side) The same lens (lens function element) is used. Since the performance of the light receiving element PSD and the performance of the light receiving lens 3 are the same, the distance between the measuring point and each light receiving lens 3 is the same, and the distance between the measuring point and each light receiving element PSD is also the same. This is for equalizing the three displacement detection sensitivity of the light receiving units 200, 210 and 220.

In addition, as shown in FIG. 2, a plane perpendicular to the object to be measured (the plane of FIG. 1 or the light receiving element PSD2 of FIG. 2) is connected to the measurement target, including an optical path of light transmitted from the light-transmitting unit 100. Preferably, the light receiving surfaces of the light receiving lenses 3a, 3b, and 3c disposed almost in a fan shape so as to intersect with the surface standing on the line) are in contact with each other. That is, as shown in FIG. 2, the light received from the light receiving lens 3a is focused on the light receiving element PSD1, the light received by the light receiving lens 3b is focused on the PSD2, and the light received by the light receiving element 3c is received. By condensing on the element PSD3, it is set as the structure which can receive the light in each angle range (light receiving range) arrange | positioned in fan shape from the light receiving lens 3a to 3c all without missing. This is because if there is a gap between the light receiving surfaces of each of the light receiving elements adjacent to each other, the light entering the gap cannot be received, which causes an error in the displacement of the measuring point at the position entered into the gap.

On the other hand, as described above, "the light receiving surfaces of the light receiving lenses 3a, 3b, and 3c arranged in a fan shape are configured so that neighboring ones come into contact with each other", that is, the light receiving surfaces of each light receiving unit (light receiving lens 3) have a measurement point. The light receiving ranges are arranged so that neighboring light receiving surfaces are continuous with each other. The light receiving ranges may be completely continuous, but there are problems such as errors in arrangement and structure. Therefore, "arrangement so that it may be continuous" here means that displacement measurement can be substantially carried out to the last as a result of arrangement | positioning. In other words, it allows discontinuity in the light receiving range without substantially affecting the measurement. For example, when light is captured as a luminous flux, as shown in FIG. 9, if at least a part of the light is input to several light receiving lenses, it can be measured, and thus there is continuity. FIG. 9 shows only the light receiving lenses 3a1, 3b1, 3c1 of FIG. 4 and rearranges them for explanation. In FIG. 9, a part of the reflected light A (the light beam in the diagonal portion) from the measurement point is missing between the light receiving lenses 3b1 and 3c1, and a part of the light is received by the light receiving lens 3b1. A part of the reflected light B (beam of oblique portion) is input to the light receiving lens 3b1, another part is input to the light receiving lens 3a1, and another part is separated between the light receiving lenses 3b1 and 3a1, and a part of the The light is received by the light receiving lens 3b1. In this way, continuity occurs by having a dimensional relationship structure in which the reflected light from the measuring point does not entirely fall out.

On the other hand, in the scanning process, for example, in the following measurement method as (a) or (b), even if the reflected light may fall out between predetermined distances, the measurement image is measured substantially continuously and the displacement thereof is measured. If it is within the error range allowable in measurement, it is assumed that the light receiving range of the light receiving surface is arranged to be continuous.

(A) Scan in the scanning direction and measure the displacement every predetermined distance (measurement resolution in the scanning direction). That is, what is necessary is just to be able to measure continuously every predetermined distance in a scanning direction. In addition, when the measurement for each predetermined distance is performed as described above, when the degree of inclination or unevenness of the measured object or the degree of flatness is expected to be the type of the measured object or the like, the predetermined distance interval is increased or partially concentrated. And some may be larger.

(B) Depending on the degree of inclination and the degree of flatness of the uneven shape of the portion to be measured, the displacement is measured at one or more intervals of the predetermined distance interval, and the value at the one or more intervals is the measured value before and after. It is also possible to make the correction as the estimated value on the line connecting the measured values before and after.

If there is no substantial adverse effect as described above, even if there is a discontinuity in the light receiving range, it belongs to the scope of the present invention. Hereinafter, about the continuation of a light receiving range, the said meaning shall be shown.

Fig. 2 is a view seen from arrow A in Fig. 1 (omission of the configuration on the light source side), and the angle of regular reflection changes depending on the position of the main scanning, and the light receiving position in the light receiving elements PSD 1 to 3; Is changing appearance. The first scanning light, the second scanning light, and the third scanning light mainly scan the measurement point with one light, but for the sake of explanation, the light when the measurement point Xn-1 on the measurement object is scanned is removed. The light at the time of scanning one scanning light and the measuring point Xn is represented as the 3rd scanning light at the time of scanning the 2nd scanning light and the measuring point Xn + 1. Light reflected by the first scanning light at an inclination of the measuring point Xn-1 (an inclination point rising to the right with respect to the main scanning direction) is focused on the light receiving element PSD1 by the light receiving lens 3a (p2), and the displacement thereof. Is measured as Lp2 = (A1-B1) / (A1 + B1). Light specularly reflected at the top of the measuring point Xn by the second scanning light is focused on the light receiving element PSD2 by the light receiving lens 3b (p1), and the displacement is Lp1 = (A2-B2) / (A2 + B2). Measured as The light reflected by the third scanning light at an inclination of the measuring point Xn + 1 (an inclination point descending to the right with respect to the main scanning direction) is collected by the light receiving lens 3c on the light receiving element PSD3 (p3), and the displacement thereof. Is measured as Lp3 = (A3-B3) / (A3 + B3). Actually, as explained in the displacement measuring device described later (see Fig. 6), displacement L = (AB) / (A + B), A = A1 + A2 + A3, and B = B1 + B2 + B3. Can be.

The measurement result is shown in FIG. 8, the horizontal axis represents dice in the main scanning direction, and the vertical axis is a displacement calculated based on the output of each light receiving element PSD. As shown in this figure, the light reflected by the specular surface is received and its shape displacement can be obtained.

[Type of optical displacement sensor]

Here, the form of an optical displacement sensor, especially the form of a light receiving part is demonstrated. The light receiving unit has embodiments as shown in the following (1) to (4) depending on the difference between the light receiving element PSD, the light receiving lens functional element, etc. constituting it, and any of them may be adopted.

(1) When the performance and function of each of the light receiving element (PSD) and the light receiving lens functional element constituting three light receiving units are the same:

As described above with reference to FIGS. 1 and 2, the distance between the measuring point and each light receiving lens 3 is the same, and the distance between the measuring point and each light receiving element PSD is also the same.

(2) When the light receiving element (PSD) of each light receiving unit has the same performance and function, but the performance and function of each light receiving lens functional element are different:

This example is described with reference to FIG. 4. Each of the light receiving lens functional elements shown in Fig. 4 is a collimator lens 3a1, 3b1, 3c1 that receives the specular reflection from the measuring point to form parallel light, and a light condensing lens for condensing the parallel light on the light receiving element PSD. (3a2, 3b2, 3c2). Here, each focal length of the collimator lens 3a1, 3b1, 3c1 is Fa1, Fb1, Fc1, and each focal length of the light condensing lenses 3a2, 3b2, 3c2 is Fa2, Fb2, Fc2, respectively. The optical magnifications Fa2 / Fa1, Fb2 / Fb2, and Fc2 / Fc1 as light receiving parts are all the same. In this case, the distance between the measuring point and each collimator lens and the distance between the measuring point and each light receiving element PSD (distances La, Lb and Lc in FIG. 4) may be different. In particular, the distance also varies between the collimator lenses 3a1, 3b1, 3c1 and the light receiving element PSD.

In this example, since the collimator lenses 3a1, 3b1, 3c1 condense the light from the measuring point, the collimator lens 3a1, the collimator lens 3b1, the collimator lens 3b1, and the collimator lens neighboring each other It is necessary that the light receiving ranges for the measuring points of each light receiving surface of (3c) be arranged so as to be continuous with each other. This is to prevent specular reflection from the measuring point from leaking between collimator lenses. In this case, the distance from the measuring point may be different depending on the difference in focal length between the collimator lenses 3a1, 3b1, 3c1 (see Fig. 4). It becomes easy to continue the light receiving range at.

(3) When the performance and function of the light receiving element (PSD) of each light receiving unit and the performance and function of each light receiving lens functional element are different:

This example is explained by comparing the two light receiving units in FIG. 5. Each of the light receiving lens functional elements shown in Fig. 5A receives collimating lenses 3b1 and 3c1 for receiving the specular reflection from the measuring point to form parallel light, and the light condensing lens for condensing the parallel light on the light receiving element PSD. (3b2, 3c2). When the focal lengths of the collimator lenses 3b1 and 3c1 are set to Fb1 and Fc1, and the focal lengths of the light condensing lenses 3b2 and 3c2 are set to Fb2 and Fc2, the optical magnifications Fb2 / Fb1, Fc2 / Fc1. 5B is an enlarged view of portions of the light receiving elements PSD2 and PSD3 in FIG. 5A. In this figure, the light receiving elements PSD2 and PSD3 are treated as the same number of divisions Q (for example, 4096) by the digital processing at the rear stage, but the ratio of the size per one division (pixel, dot) of such processing is processed. (One compartment size of PSD2 / one compartment size of PSD3) is equal to the ratio {(Fb2 / Fb1) / (Fc2 / Fc1)} of the optical magnification. As a result, the sensitivity per compartment that the light receiving element PSD2 and the light receiving element PSD3 receive from the same light becomes the same. Therefore, also in this embodiment, the distance from the measuring point to each of the light receiving elements PSD1 to 3 can be different for each light receiving unit. The idea is that even when CCDs, CMOS devices, and the like are arranged as arrays of light receiving elements (PSDs), the number of pixels (for example, the number of CCD elements) is the same between the light receiving elements, and the size per pixel (for example, The size of the CCD element) can be used by using a structure having a different configuration.

(4) In the above 3, although the performance and function of each light receiving lens functional element of each light receiving unit are different, the performance and function of the light receiving element (PSD) are the same, and the offset, sensitivity, etc. are determined by software or amplifier gain. If you adjust:

The optical magnification (sensitivity) and offset differ depending on the performance and function of each of the light receiving lens functional elements, but the amount is adjusted by software or amplifier. That is, even if the magnification is different from Fb2 / Fb1 and the magnification Fc2 / Fc1 as in (3) above, the position of the image received by the light receiving elements PSD2 and PSD3 of the same function and performance does not change, and thus can be adjusted by the software or the amplifier. have.

[Displacement measuring device]

Based on FIG. 6, embodiment of the displacement measuring apparatus using the optical displacement sensor mentioned above is demonstrated.

In Fig. 6, the optical displacement sensor 4 simply shows the displacement sensor described in Figs. In the optical displacement sensor 4, the light source LD and the light receiving elements PSD 1 to 3 in FIG. 1 are described. In FIG. 6, the control unit 6, the syringe port 5, the adders 7 and 8, the calculator 9, and the image processing unit 10 constitute a displacement measuring unit 300.

The control part 6 of FIG. 6 has the layout information about the surface of a to-be-measured object which is necessary for previously scanning and measuring the surface of a to-be-measured object, and is orthogonal to a main scanning range, the frequency | count, and a main scanning direction based on the layout. The sub-scan range and the number of times in the direction to be determined are determined, and the start of the injection is instructed along with the instructor 5 being instructed. On the other hand, information on the position at the time of scanning, that is, position information of the measuring point is output.

The syringe port 5 is provided with a drive mechanism and means for moving the optical displacement sensor 4 and the object to be measured in the main scanning direction and in the sub scanning direction in accordance with the instructions on the control section 6. do. For example, such a means is provided by moving the optical displacement sensor 4 linearly in the main scanning direction, and moving the object under test in a direction orthogonal to the main scanning direction when one main scanning is completed. Scan the measuring point according to 4) relatively.

The adder 7 adds the respective outputs A1, A2, A3 of the upper ends of the light receiving elements PSD1 to 3, outputs A = A1 + A2 + A3, and the adder 8 receives the light receiving elements PSD1-. Each output B1, B2, B3 at the bottom of 3) is added, and B = B1 + B2 + B3 is output. Based on these outputs A and B, the calculator 9 calculates and outputs output L = (A-B) / (A + B) as displacement information. On the other hand, when the measurement object has a strong directivity of the reflected light on the mirror surface, since there is only one specularly reflected light from the measurement point, it is input to either of the light receiving elements PSD1 to 3, so that the output L1 = (A1-B1) / ( A1 + B1), output L2 = (A2-B2) / (A2 + B2) or output L3 = (A3-B3) / (A3 + B3) The operation result of (A + B) is the same.

As shown in Fig. 8, the displacement measuring device can be obtained by plotting the output of the calculator 9 with respect to the positional information of the control unit 6 as long as the measurement point and the displacement are plotted. The image processing unit 10 is for reproducing the surface shape of the object to be measured as a three-dimensional image in which each pixel consists of displacement information based on the output of the calculator 9 and the positional information of the control unit 6. An image having three main dimensions in the main scanning direction, the sub scanning direction, and the displacement direction may be calculated and output.

[Shape Inspection Device]

7, the embodiment used for the shape inspection apparatus which examines the displacement of the surface of a to-be-measured object using the displacement measuring apparatus using the optical displacement sensor 4 demonstrated above is demonstrated. For example, the electronic component is mounted on a printed board, and it is also effective for determining whether the solder state of the inclined surface is particularly good after reflow. In FIG. 7, the control part 6, the comparison means 11, the determination means 12, and the display means 13 comprise the inspection part 400. As shown in FIG.

The image processing unit 10 measures an area (collecting area of measuring points: for example, cream solder printed on a printed circuit board) measured at the output of the calculator 9 and the position (coordinate) of the measuring point of the measurement target object from the control unit 6. Image data indicating an area (for example, a solder-printed area) and a volume (for example, an amount of solder) on the surface) are generated. The comparing means 11 receives the design value or the like in the area from the control part 6 as a reference (area or volume), calculates and outputs the difference between the image data and the reference. On the other hand, the difference between the displacement measured at the measurement point (height: for example, the height of the solder) and the reference (in this case, the design height at the measurement point, for example) without being converted into image data is output. You may also

The judging means 12 receives the allowable value from the control part in response to the reference, compares it with the output from the comparing means 11, and makes a pass if the output of the comparing means 11 is within the allowable value. If it is, it is determined that it is defective.

The display means 13 displays the determination result of the determination means 12. In addition, layout information (for example, a layout of soldering points of a printed circuit board) is received from the control unit 6 and displayed, and it is possible to display which position of the layout is defective (negative) and can be discriminated. In addition or in addition to these, an image based on the image data generated by the image processing unit 10 can be displayed, and it can be displayed so that it can be discriminated whether any part is defective or passed.

When the surface shape of the object to be measured is inspected using the optical displacement sensor of the compound eye, it is possible not only to check the vertex or flat portion but also to check the quality determination including the shape of the inclined portion.

In the above description, although the inclination and the vertices of the convex portions of the surface of the object under measurement are measured in the present embodiment as shown in FIG. Even if it is a part, the displacement of the inclination part and the bottom part can be measured also by the width | variety of the opening part of the recessed part.

[Example with two optical displacement sensors]

Fig. 10A shows a shape inspection apparatus provided with two of the same optical displacement sensors 4a and 4b as the optical displacement sensor shown in Fig. 1 or 6. The displacement measuring device may be used instead of the shape inspection device. In Fig. 10, elements having the same reference numerals as those shown in Figs. 1 to 6 have the same functions. In Fig. 10, the optical displacement sensor 4a and the optical displacement sensor 4b are the same, and have the same light transmitting portion 100 and the same light receiving portion 200, 210, 220, respectively. And the optical displacement sensor 4a and the optical displacement sensor 4b are arrange | positioned in the direction orthogonal to a main scanning direction mutually. They are the sealing material 600 provided in the rectangular shape in the base material as shown to FIG. 10 (B), for example, and are used for measuring the bulging shape like FIG. 10 (C). That is, the optical displacement sensor 4a measures the shape of the sealing member 600 in the upper limit direction on the drawing in FIG. 10 (B), and the optical displacement sensor 4b is in the horizontal direction on the drawing in FIG. 10 (B). The sealing material 600 is measured. And each output of each optical displacement sensor 4a or 4b is switched to the switch S of FIG. 10 (A), and it passes through the displacement measuring part 300 and the inspection part 400, and an inspection result is displayed on display means ( 13).

Switching of the optical displacement sensor 4a and the optical displacement sensor 4b and switching of the switch S are switched by the controller 6. As shown in Fig. 11, the operator controls the switching instruction by the operation means (not shown) while checking the image of the measurement point photographed by the camera 500 provided on the measurement point with the display means 13. Output to.

In this way, the optical displacement sensor 4 may be converted into a transducer tool whenever the optical displacement sensor 4 has one optical displacement sensor 4 and the measurement direction is different without preparing two optical displacement sensors. Minor reproducibility of accuracy has been a problem. In addition, reproducibility is susceptible to changes over time of the transducer tool. In the example of FIG. 10 (A), two optical displacement sensors 4a and 4b are provided in order to perform the measurement with good reproducibility even if the measurement direction is different.

The present invention has a configuration in which the optical displacement sensor includes a light receiving unit capable of detecting a plurality of lights at different angles, and thus has a so-called compound eye function, so that the optical displacement sensor can receive light in response to the shape change of the measuring point during scanning. It can be measured immediately by scanning the displacement according to. Moreover, since there is no mechanism which rotates a monocular optical displacement sensor like the conventional patent document 1, it can be comprised easily.

Claims (11)

And a light displacement sensor having a light projecting portion 100 for irradiating the collected light as a measuring point by condensing light on the object to be measured and a light receiving portion 210 for receiving the reflected light specularly reflected from the measuring point. A displacement measuring apparatus for scanning by moving the optical displacement sensor in a direction orthogonal to a plane perpendicular to the plane to be measured, including the light to be transmitted, and measuring the displacement of the object to be measured. At least three or more light receiving parts are provided with respect to one of the light sources, and any one of the plurality of light receiving parts is inclined portions Xn-1 (Xn +) on both sides in the cross section along the plane of the object to be measured. 1) and a plurality of light receiving units arranged around the measuring point so as to receive the reflected light reflected by any one of the top portion (Xn) between the measurement point, displacement measurement Device. The method of claim 1, Arranging the plurality of light receiving parts about the measurement point, The light receiving ranges in which the plurality of light receiving parts are arranged in the direction crossing the plane toward the measuring point and which receive the specularly reflected reflected light from the measuring point occupied by the light receiving surface of each light receiving part are adjacent to each other in displacement measurement. Displacement measuring device, characterized in that arranged so as to be continuous with the light receiving surface. The method of claim 2, And said plurality of light receiving sections are arranged symmetrically by one at a point intersecting the plane and the same number on both sides of the direction intersecting the plane. The method of claim 2 or 3, The light transmitting portion includes a light source LD and a light collecting lens 2 for irradiating a light collected position as a measuring point by condensing the light emitted from the light source on a measurement target, The plurality of light receiving units may include light receiving lens functional elements 3a, 3b, and 3c that receive and reflect light reflected from the measurement point, and light receiving elements PSD1, PSD2, and PSD3 that receive light collected by the light receiving lens functional element. Equipped, The light receiving surface of the light receiving unit is a light receiving surface of the light receiving lens functional element. The method of claim 4, wherein The distances from the plurality of light receiving lens functional elements to the condensed position are the same, and each of the light receiving lens functional elements is disposed at the same distance from the measuring point, and the light receiving surfaces of adjacent light receiving lens functional elements are in contact with each other. Displacement measuring device, characterized in that disposed on. The method of claim 5, wherein Each of the light receiving lens functional elements receives collimating lenses 3a1, 3b1, 3c1, which receive light reflected by the measuring point into parallel light, and the light receiving lens for condensing parallel light from the collimating lens on the corresponding light receiving elements. With condensing lenses 3a2, 3b2, 3c2, The light receiving surface of the light receiving portion is a light receiving surface of the collimator lens, and the light receiving ranges occupied by the light receiving surfaces of neighboring collimator lenses with respect to the measuring point are arranged so as to be continuous with each other in displacement measurement. The device according to claim 1, wherein the ratio of the distance between the measuring point and the collimator lens and the distance between the light condensing lens and the light receiving element is the same. The method of claim 2 or 3, The optical displacement sensor is provided with two, and each said scanning is a structure arrange | positioned so that scanning in a different direction is possible, The displacement measuring apparatus characterized by the above-mentioned. delete delete delete delete

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