JP2006337117A - Optical measurement apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical measurement apparatus capable of measuring at high speed and high accuracy, using a comparatively simple constitution. <P>SOLUTION: The main body of the measurement apparatus 30 is provided with the light projector 31 for emitting light, the objective lens 39, the image sensor 51, the light-receiving pinhole array 55, and the 1st light guiding means 41 and the 2nd light-guiding means 45. For measuring the 3-dimensional shape of the work W, light is made to scan the work W by making the light projection pin hole array 35 undergo reciprocative movements. At this time, the light-receiving pinhole array 55 is required to be moved in synchronization with the light projection pinhole array 35. In the embodiment, since the light-receiving pinhole array 55 and the light projection pinhole array 35 are connected by the slider 63, they move reciprocatively as a unit. Thus, mechanism for synchronization is not needed. Accordingly, the optical measurement apparatus, capable of measuring at a high speed and with high accuracy, can be provided. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an optical measuring device.

  Conventionally, optical measuring apparatuses using the principle of confocal are widely known. In this apparatus, light from a light source is condensed by a measurement optical system so as to be focused on a workpiece. The light reflected by the workpiece passes through the pinhole and is then detected by the light detection unit. As a result, when the focal point is actually focused on the work, the light detection unit increases the amount of light received, whereas when the focal point is focused on the work due to the unevenness of the work surface, The amount of received light is reduced. As described above, the unevenness on the surface of the workpiece is measured based on the amount of light received by the light detection unit.

In this type of optical measurement apparatus, measurement is performed by scanning light from a light source on a workpiece. However, since there is one point to be measured for each light source, many light sources are used for the purpose of speeding up the measurement. What is made into a point type is proposed (patent document 1). The thing of patent document 1 is provided with the pinhole array which has a some pinhole ahead of the laser light source, and is trying to obtain a some point light source. Further, the pinhole is movable, and when the pinhole is moved, the light from each point light source scans the workpiece.
In such an optical system, in order to receive the light from the point light source through the pinhole on the light receiving side, the light receiving side (spatial filter) that is the other side as the light projecting side (pinhole array) moves. It is necessary to move the array) at a timing synchronized with this. This is because if both arrays move apart, even if the light from the point light source is focused on the measurement object, the reflected light passes through the pinhole of the spatial filter array. Without causing a measurement error.
Japanese Utility Model Publication No. 5-33109

As described above, synchronizing the movements of both arrays is extremely important for compensating measurement accuracy. On the other hand, in the previous document, the moving direction of the pinhole array is the vertical direction shown in FIG. 11, whereas the moving direction of the spatial filter array on the other side is the horizontal direction. The moving direction of is different. As described above, it is generally difficult to move both members having different moving directions, that is, a pinhole array and a spatial filter array at a synchronized timing. Even if they can be synchronized, synchronous control is performed. This requires a mechanism for increasing the cost.
The present invention has been completed based on the above-described circumstances, and an object thereof is to provide an optical measurement apparatus capable of performing measurement at high speed and high accuracy with a relatively simple configuration. .

  As means for achieving the above object, the invention of claim 1 condenses the light emitted from the light projecting light source so as to focus on the object to be measured, and images the reflected light to obtain an image signal. The optical device main body that outputs the above, a mounting table on which the measurement object is mounted, and at least one of the optical device main body or the mounting table described above is moved in the optical axis direction of the light, and the optical Relative movement means for moving the measurement object relative to the optical system of the apparatus main body, and shape determination means for determining the shape of the measurement object based on the imaging signal at each point of time relative movement by the relative movement means And the optical device body is emitted from the light projecting means having the plurality of light projecting light sources arranged periodically with a predetermined interval, and from the plurality of light projecting light sources, respectively. An objective lens for condensing the emitted light on the measurement object; and a light branching means for branching the reflected light reflected by the measurement object and then passed through the objective lens in a direction different from the light projecting means; A light receiving pinhole array disposed at a position optically conjugate with the light projecting means, and an opening at the same interval as or similar to the arrangement interval of the light projecting light sources on the light receiving pinhole array; A light receiving pinhole for individually passing the reflected lights branched by the light branching means while being converged by the light branching means, and an imaging surface on which the reflected lights passing through the light receiving pinholes are incident. Imaging means capable of outputting the imaging signal according to the amount of the emitted light, and the light projecting means and the light receiving pinhole array include an output optical axis of the light projecting means and the light emitting means. The optical pinholes are arranged so that the axes (center lines) thereof are parallel to each other, and are configured to move integrally in a direction orthogonal to the outgoing optical axis, so that the light from the light projecting light source is received. It is characterized in that an optical scanning mechanism that enables optical scanning is formed on an object to be measured.

The “relative movement means” described in claim 1 includes a measurement function capable of measuring the movement amount when the relative movement is performed in the optical axis direction. The “shape determining means” described in claim 1 includes a relative movement amount in the optical axis direction obtained from the relative movement means, a light receiving position on the image pickup means at each point of relative movement, and a light receiving position at the light receiving position. The shape of the object to be measured is determined based on the received light signal intensity.
Further, “the optical device main body or at least one of the mounting tables” described in claim 1 is a part of the optical device main body (for example, an objective) in addition to the optical measuring device main body and the mounting table. Lens).

  According to a second aspect of the present invention, there is provided the apparatus according to the first aspect, further comprising a converging means for converging the reflected light that has passed through the light receiving pinhole and entering the imaging surface.

  The invention of claim 3 is the one described in claim 2, wherein the converging means comprises a converging lens group consisting of a collection of converging lenses provided individually for each of the light receiving pinholes, The converging lens group is characterized in that it is integrated with the light receiving pinhole array. Each of the light receiving pinholes includes a plurality of converging lens groups that are individually provided, and the plurality of converging lens groups are integrated with the light receiving pinhole array.

According to a fourth aspect of the present invention, there is provided the optical path of the total reflected light according to the second aspect, wherein the converging means is located between the light receiving pinhole array and the imaging means, and has a size passing through the light receiving pinholes. It is characterized in that it consists of a single converging lens formed in a size over the entire length.
The “single converging lens” in claim 4 means a converging lens having a single optical axis, which includes an achromatic lens, a triplet lens, or two groups composed of a plurality of lenses. A lens unit such as a lens is also included.

  According to a fifth aspect of the present invention, the shape determining means according to any one of the first to fourth aspects, wherein a predetermined time or more has elapsed since the integrated movement of the collimator lens and the imaging means was started. It is characterized in that the shape of the measurement object is determined based on an imaging signal of light incident on the imaging means.

  A sixth aspect of the present invention is characterized in that, in any one of the first to fifth aspects, the relative moving means comprises objective lens moving means for moving the objective lens in the optical axis direction. Have.

A seventh aspect of the present invention is the light emitting device according to any one of the first to sixth aspects, wherein the light projecting means is a light projecting device in which a plurality of light projecting elements are periodically arranged at predetermined intervals on a support member. It is characterized by a device array.
Examples of the “light projecting element array” described in claim 7 are VCSEL (surface emitting semiconductor laser), DMD (reflection type optical element (digital micromirror device)), and the like.

  Other means may be as follows. That is, in the invention according to any one of claims 1 to 4, the optical scanning mechanism includes a slider that holds the light projecting means and the light receiving pinhole array in a connected state, and the slider is slidably supported. The base member is configured to perform scanning of light on the object to be measured by moving the slider from the movement start position. The movement start position of the slider is determined by the movement of the slider being started. After a predetermined time or more has elapsed, light from a light projecting source enters the measurement range region of the measurement object, and scanning for shape detection is performed.

  Further, a collimator lens may be added to the invention described in claim 1. That is, the light emitted from the light projecting light source is collected so as to be focused on the object to be measured, and the optical device main body that images the reflected light and outputs an imaging signal, and the measurement object are mounted. And moving the measurement object relative to the optical system of the optical device main body by moving at least one of the mounting table and the optical device main body or the mounting table described above in the optical axis direction of the light. An optical measurement apparatus comprising: a relative movement unit; and a shape determination unit that determines a shape of an object to be measured based on an imaging signal at each time point relatively moved by the relative movement unit. Includes a light projecting unit having a plurality of the light projecting light sources arranged periodically with a predetermined interval, a collimator lens for making each light emitted from the plurality of light projecting light sources substantially parallel light, An objective lens that condenses each output light that has been made substantially parallel light by the collimator lens onto the measurement object, and is reflected by the measurement object, and then the reflected light that has passed through the objective lens and the collimator lens is projected. A light branching means for branching in a direction different from the light means, a light receiving pinhole array disposed at a position optically conjugate with the light projecting means, and an arrangement interval of the light projecting light sources on the light receiving pinhole array A light receiving pinhole that individually passes the reflected light branched by the light branching means while being converged by the collimator lens, and each reflected light that has passed through the light receiving pinhole is incident. And an imaging means capable of outputting the imaging signal in accordance with the amount of incident light. The light receiving pinhole array is arranged so that the output optical axis of the light projecting means and the axis of the light receiving pinhole are parallel to each other and move integrally in a direction perpendicular to the optical axis of the emitted light The optical measurement device is configured so as to form an optical scanning mechanism that allows the light from the light projecting light source to be optically scanned on the object to be measured.

<Invention of Claim 1>
According to the first aspect of the present invention, the light scanning mechanism for scanning the object to be measured is constituted by the light projecting means and the light receiving pinhole array, and the light projecting means and the light receiving pinhole array move integrally. Is configured to do. With such a configuration, the relative positional relationship between the light projecting means and the collimator lens does not change due to the movement, and compared with the case where the light projecting means and the light receiving pinhole array are moved independently. Thus, the configuration of the apparatus can be simplified (no mechanism is required for synchronization).

<Invention of Claims 2 to 4>
According to the second to fourth aspects of the present invention, the light that has passed through the light receiving pinhole enters the imaging unit while being converged by the converging unit. Thereby, compared with the case where the convergence means is not provided, the light receiving spot on the imaging means can be imaged smaller, so that the measurement accuracy is improved.

  According to the invention of claim 4, the converging means is constituted by a single converging lens. With such a configuration, a general-purpose lens can be used as the converging means, which contributes to cost reduction.

<Invention of Claim 5>
Immediately after the start of movement of the light projecting means and the light receiving pinhole array, the speed is often not stable, and there is a risk that accurate shape measurement will not be performed. However, according to this configuration, the shape determining means determines the shape of the measurement object based on the imaging signal after a predetermined time or more has elapsed since the start of movement. In other words, since the imaging signal when the speed immediately after the start of movement is not stable is excluded, the measurement accuracy is increased.

<Invention of Claim 6>
In order to move the measurement object relative to the optical system of the optical device main body, it is only necessary to move at least one of the optical device main body (including part of the optical device main body) or the mounting table in the optical axis direction of the light. However, according to the invention of claim 6, the objective lens is moved and relatively moved. With such a configuration, since the component (objective lens) to be moved is relatively small, the mechanism for movement can be reduced in size and simplified.

<Invention of Claim 7>
According to the invention of claim 7, the light projecting means is constituted by the light projecting element array and can be handled as one component. Further, by adopting such a configuration, the following effects can be obtained as compared with a configuration in which a plurality of independent single light sources are arranged to constitute the light projecting means. First, miniaturization is possible. Second, position adjustment between the light sources is not necessary. Third, there is no brightness spot (because the elements can be arranged at high density). Fourthly, the life is increased.

<Embodiment 1>
A first embodiment of the present invention will be described with reference to FIGS.

1. Overall Configuration of System An optical measuring apparatus includes an elevating mechanism (corresponding to the relative movement means of the present invention) 10 for moving up and down a mounting table 15 on which a workpiece W as a measurement target is placed in FIG. The processing unit (corresponding to the shape determining means of the present invention) 20 and the optical device main body 30 are mainly configured.

2. Configuration of Optical Device Body The optical device body 30 includes a light projecting unit (corresponding to the light projecting means of the present invention) 31 that emits light, a collimator lens 38, and an objective lens 39, and an image sensor (imaging of the present invention). 51), corresponding to the light receiving pinhole array 55, the first light guide means 41, and the second light guide means 45.

  The light projecting unit 31 includes a light projecting pinhole array 35 having a light source 32, a collimator lens 33, and a plurality of light projecting pinholes 36. In addition, microlenses 37 are attached to the upper surface of each light projecting pinhole array 35 and at the entrance portion serving as the light introduction port of each light projecting pinhole 36. From the above, when light is emitted from the light source 32, the light is converted into parallel light by the collimator lens 33.

  Thereafter, the parallel light is converted into convergent light by the microlens 37, but diverges after passing through the light projecting pinhole 36. Accordingly, the light projecting unit 31 functions as a plurality of point light sources (corresponding to a plurality of light projecting light sources according to the present invention) that emit diverging light downward in the drawing in FIG.

  FIG. 2 shows the arrangement of the light projecting pinholes 36. The light projecting pinholes 36 are arranged at a predetermined interval so that the point light sources do not interfere with each other, but are regularly arranged so as not to overlap in both the X-axis direction and the Y-axis direction. Is wide in the X axis direction and narrow in the Y direction. The reason why the interval is wide in the X-axis direction is that the light scanning direction by the optical scanning mechanism described later is made in the X-axis direction.

  The first light guiding unit 41 guides each light emitted from the light projecting unit 31 to the collimator lens 38 and includes a first total reflection mirror 42 and a second total reflection mirror 44. The first total reflection mirror 42 is disposed below the light projecting unit 31, while the second total reflection mirror 44 is disposed opposite to the right side of the first total reflection mirror 42. The collimator lens 38 and the objective lens 39 are arranged side by side below the second total reflection mirror 44.

  From the above, the direction of each light emitted from the light projecting unit 31 is changed in the right direction by the first total reflection mirror 42 and then changed in the downward direction by the second total reflection mirror 44. Then, after being changed to parallel light by the collimator lens 38, it is condensed by the objective lens 39 so as to be focused on the workpiece W.

  The second light guide means 45 guides the light reflected on the workpiece W to the light receiving pinhole array 55 described below. In the present embodiment, this is a beam splitter (light branching means of the present invention). 46 and the third total reflection mirror 48. The beam splitter 46 is disposed between the collimator lens 38 and the second total reflection mirror 44, while the third total reflection mirror 48 is disposed so as to face the beam splitter 46.

  Thus, after the reflected light reflected on the workpiece W passes through the objective lens 39 and the collimator lens 38, it is reflected in the right direction in the figure by the beam splitter 46 and then reflected upward in the figure by the total reflection mirror 44.

  In this way, the second light guide means 45 is formed by the beam splitter 46 and the third total reflection mirror 48, and the light reflected on the workpiece W is reflected a plurality of times (twice), so that the reflected light is reflected. The optical axis (hereinafter also referred to as the light receiving axis) L1 is parallel to the light projecting axis (corresponding to the outgoing optical axis of the present invention) L0 of the light traveling from the light projecting unit 31 to the workpiece W.

  Thus, the light receiving pinhole array 55 described below is oriented in the same direction as the light projecting pinhole array 35. More specifically, the axis lines of the pinholes 36 and 56 formed in both the arrays 35 and 55 are both in the vertical direction. It becomes possible to arrange so that it may face.

  In the light receiving pinhole array 55, a plurality of through holes (light through holes, hereinafter referred to as light receiving pinholes 56) are formed in a flat plate-shaped light shielding member at the same interval as the light emitting pinholes 36 are arranged. It is arranged at a position that is optically conjugate with the light projecting pinhole array 35. That is, the light receiving pinhole array 55 is arranged at a position where the reflected light emitted from the light projecting unit 31 and reflected on the work W is focused.

  Further, the light projecting axis L0 and the light receiving axis L1 are symmetric with respect to the central axis (lens axis of the objective lens 39) L of the optical system, and the emission position of the point light source (positioning position of the light projecting pinhole array 35). In this embodiment, the beam splitter is arranged so that the focal point (the arrangement position of the light receiving pinhole array 55) is the same height in the vertical direction in FIG. 1 after the light is reflected by the workpiece W. 46 and the arrangement of the third total reflection mirror 48 are as follows.

  That is, although the beam is displaced in the vertical direction, the beam splitter 46 is arranged substantially symmetrically with the second total reflection mirror 44 when the central axis L is the center, and further, the third total reflection The reflection mirror 48 is arranged substantially symmetrically with the first total reflection mirror 42.

  In addition, microlenses 57 are respectively attached to openings on the exit (upper surface shown in FIG. 1) side of the respective light receiving pinholes 56. The microlens 57 functions to make the light that has passed through the light receiving pinhole 56 enter the imaging surface 51A of the image sensor 51 while converging. The group of microlenses 57 corresponds to the converging lens group (convergence means) in the present invention.

The image sensor 51 includes a two-dimensional CCD having an imaging surface 51A in which light receiving elements (also referred to as pixels, not shown) are arranged in a matrix, and is arranged in parallel to the light receiving pinhole 56 at a predetermined interval. Has been. When the light converged by the microlens 57 enters, the imaging signal Sc having a voltage level corresponding to the amount of received light is output.
In FIG. 1, in order to make the optical path of light easy to understand, a state in which light is emitted from one point light source is illustrated, but in FIG. 5, light from a plurality of (two) point light sources is illustrated. The state in which is emitted is illustrated.

3. Optical Scanning Mechanism A slide mechanism 60 is provided below the image sensor 51. The slide mechanism 60 includes a slider base 61 and a slider 63. Based on a control signal Sd from the processing unit 20, the slide mechanism 60 moves the slider 63 in the horizontal direction in FIG. 1 (more specifically, in the X-axis direction in FIG. 2). It moves forward and backward at a stable speed.

  The right end portion of the light projecting pinhole array 35 and the left end portion of the light receiving pinhole array 55 are respectively fixed to the left and right end portions of the slider 63. When the slider 63 is advanced and retracted, the light projecting pinhole array is integrated with the slider 63. 35 and the light receiving pinhole array 55 are horizontally moved. Thereby, the light emitted from the light projecting unit 31 is scanned on the workpiece W.

  With reference to FIG. 3, the light scanning will be specifically described. FIG. 3 is a diagram showing an optical path of light when the slider 63 is moved in the right direction of FIG. 1 by a distance D from the state of FIG. As shown in the figure, when the slider 63 is moved, the light incident position of the light incident on the center position A0 of the collimator lens 38 in the state of FIG. 1 moves to the outer point A1, so that the light is collimated. The light is refracted in the direction toward the center of the lens. As a result, the light is incident on the objective lens 39 at an angle, so that the light irradiated to the position B0 on the workpiece W before the slider movement is changed to the position B1 on the workpiece W after the slider movement. Is irradiated.

  The light irradiated onto the workpiece W is reflected by the surface of the workpiece W, and then travels back to the light projecting unit 31 side by following the above-described path in the reverse direction, and in the middle of the beam splitter 46 and the total reflection mirror 48. To the light receiving pinhole array 55. Since the light receiving pinhole array 55 moves integrally with the light projecting pinhole array 35, the conjugate relationship between both members is maintained even after the movement, so that the reflected light passes through the light receiving pinhole 56. In the state of FIG. 1 before the movement, the light that has entered the position of C0 on the imaging surface 51A enters the position of C1 after the movement, as shown in FIG.

  Thus, the light can be scanned on the workpiece W by moving the slider 63 in the horizontal direction. When the scanning of the workpiece W is completed, the lifting mechanism 10 is driven by a command from the processing unit 20.

  The raising / lowering mechanism 10 raises / lowers the entire work W together with the placement table 15 in the vertical direction shown in FIG. 1. For example, every time a command is issued from the processing unit 20, the raising / lowering mechanism 10 is raised and stopped at predetermined intervals. At each time when the mounting table 15 is stopped, the workpiece W is scanned with light, the reflected light is imaged by the image sensor 51, and the imaging signal Sc is output to the processing unit 20. Thus, the image pickup signal Sc is obtained at each position in the vertical direction, and this is processed by the processing unit 20 (more specifically, the stop interval of the mounting table 15, the light receiving position obtained from the image pickup signal Sc, and By performing data processing based on the received light signal intensity at the light receiving position, the three-dimensional shape of the workpiece W can be measured.

  As described above, in this embodiment, light is scanned on the workpiece W in order to measure the three-dimensional shape of the workpiece W. This scanning is advanced and retracted by the projection pinhole array 35. By doing. At this time, it is necessary to advance and retract the light receiving pinhole array 55 at a timing synchronized with the light projecting pinhole array 35. However, if both arrays 35 and 55 are provided with dedicated drive systems, the advancement and retraction operations are independent of each other. If this is done, a control mechanism for synchronization is required, and the configuration of the entire apparatus becomes complicated. However, in this embodiment, the light projecting pinhole array 35 and the light receiving pinhole array 55 are connected by a slider 63 and integrated. Therefore, both arrays do not shift in position with movement, and no mechanism for synchronization is required. Therefore, it is possible to provide an optical measurement apparatus that can perform measurement at high speed and high accuracy with a relatively simple configuration.

  Moreover, although the thing of this embodiment has taken the structure which receives the light which passed the light-receiving pinhole 56 with the image sensor 51, generally the light which passed the light-receiving pinhole 56 is Fig.4 (a). As shown in FIG. 4, the light enters the image sensor 51 while diverging. Therefore, in order to make the light receiving spot formed on the imaging surface 51A small (if the light receiving spot becomes large, the light receiving spot is formed over adjacent pixels, which causes a measurement error), the image sensor 51 is used. However, there is a limit to this.

  Therefore, in the present embodiment, as shown in FIG. 4B, a microlens 57 is provided on the back surface of the light receiving pinhole array 55 to enter the image sensor 51 while converging the light passing through the light receiving pinhole 56. I am making it light.

Thereby, since the light receiving spot on the imaging surface 51A can be imaged small, it is avoided that the light receiving spot is formed across the adjacent pixels, and the measurement accuracy is improved.
In addition, since the amount of light incident on the imaging surface 51A increases accordingly, the following effects can be obtained. That is, the time required for accumulating the charge necessary for measurement in the light receiving element (pixel) is shortened, so that the time required for shape measurement can be shortened.

<Embodiment 2>
Next, Embodiment 2 of the present invention will be described with reference to FIG.
In the first embodiment, the microlens 37 is individually provided at the exit portion of each light receiving pinhole 56, thereby converging the light that has passed through each light receiving pinhole 56. Instead, a single converging lens 75 is provided, thereby converging light. Since other configurations are the same as those in the first embodiment, the same components are denoted by the same reference numerals and description thereof is omitted.

  As shown in FIG. 6, in the second embodiment, the image sensor 51 is arranged with a wide interval with respect to the light receiving pinhole array 55, and a converging lens 75 is provided between the two. . The converging lens 75 is formed to have a size over the entire length of the optical path width of the light that has passed through each light receiving pinhole 56 (width indicated by the F section in FIG. 6), and passes through each light receiving pinhole 56. Each of the received lights enters the image sensor 51 while being converged by the converging lens 75.

  As described above, even when the converging lens 75 is provided in place of the microlens 57, the same effect as that of the first embodiment, that is, the light receiving spot can be imaged small, so that the measurement accuracy is improved. Further, since the amount of light incident on the image sensor 51 is increased, the time required for accumulating charges necessary for measurement can be shortened accordingly, and thus optical scanning can be performed at high speed. .

  In addition, the microlens 57 in the first embodiment needs to be provided exclusively in accordance with the size and arrangement of the light receiving pinholes 56, which increases the cost accordingly. Since a general-purpose one can be used, the cost can be reduced.

<Embodiment 3>
Embodiment 3 of the present invention will be described with reference to FIG.
In the third embodiment, the configuration of the entire system is the same as that of the first embodiment. However, in order to increase the measurement accuracy, after the moving speed of the slider 63 reaches a predetermined speed, light is applied to the measurement area on the workpiece surface. Irradiation is started.

  As described in the first embodiment, the slide mechanism 60 moves the light projecting pinhole array 35 and the light receiving pinhole array 55 together with the slider 63 at a stable speed. However, as shown in FIG. The speed rises gently immediately after the start, and reaches the target speed V0 after a predetermined time t1.

  Therefore, in the present embodiment, the time t1 is anticipated in advance, and light is scanned on the workpiece W after the time t1 has elapsed since the movement by the slider 63 is started. That is, as shown in FIG. 7B, the movement stroke of the slider 63 is first provided with a spare area for increasing the movement speed to the target speed V0 following the movement start position. Even in the spare area, the light is emitted from the light projecting unit 31, but the light is set to be irradiated outside the measurement area of the workpiece W. Then, an actual scanning area is provided following the spare area. When the slider 63 reaches this scanning area, light is first irradiated into the measurement area of the workpiece W.

  As described above, when the slider 63 reaches the target speed V0 and stabilizes the speed, the light is irradiated onto the measurement area of the work W. The same amount of light is irradiated on the work W for the same time. Since the point can be irradiated, the measurement accuracy is increased accordingly.

  In addition, the following modifications are also possible. That is, since it is sufficient that the slider 63 reaches the scanning area, light is irradiated within the measurement area of the workpiece W. Therefore, when the slider 63 is in the spare area, the light is emitted from the light projecting unit 31. It may be stopped.

Further, when optical scanning is performed by periodically reciprocating the slider 63, the speed is not stable before and after the folded portion where the operation is reversed. Therefore, in such a case, if the configuration is such that the data in the region where the speed of the portion before and after the turn-back is not stable is omitted from the measurement, the measurement accuracy will be increased as in the case of the present embodiment.
As described above, the portion where the speed is not stable is positively excluded from the measurement data. In the present invention, “the shape determining unit moves the collimator lens and the imaging unit integrally. Corresponds to “determining the shape of the measurement object based on the imaging signal of the light incident on the imaging means after a lapse of a predetermined time from the start”.

<Embodiment 4>
Next, Embodiment 4 of the present invention will be described with reference to FIG.
In the first embodiment, the projection pinhole array 35 is moved only in one direction (X-axis direction), but in the fourth embodiment, the projection pinhole array 35 is moved in two directions (X-axis direction and Y-axis direction). Accordingly, the arrangement of the projection pinholes 83 formed in the projection pinhole array 81 is changed to a lattice arrangement as shown in FIG.

With such a configuration, the amount of movement of the slider 63 with respect to the X-axis direction may be A, and the amount of movement of the slider with respect to the Y-direction may be B. Therefore, the amount of movement in the X-axis direction is smaller than in the first embodiment. Thus, the moving mechanism for scanning (the slide mechanism in the first embodiment) can be expected to be downsized.
With the change in the arrangement of the light projecting pinholes 83, the arrangement of the light receiving pinholes formed in the light receiving pinhole array must also be arranged in a grid pattern (not shown).

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention, and further, within the scope not departing from the gist of the invention other than the following. Various modifications can be made.

  (1) In the above embodiment, the light projecting unit 31 is composed of a plurality of optical components such as the light source 32, the collimator lens 33, and the light projecting pinhole array 35, but the light projecting unit 31 has a plurality of point light sources. For example, as shown in FIG. 9, a light projecting device array 85, that is, a surface light emitting device 87 that emits laser light in a direction perpendicular to the substrate 86 (for example, VCSEL) is arranged. It may be configured. In this case, the right end portion of the light projecting element array 85 is fixed to the slider 63, and the light projecting element array 85 and the light receiving pinhole array 55 move together with the slider 63.

  (2) In the first embodiment, the mounting table 15 is moved up and down by the lifting mechanism 10. However, it may be anything as long as the workpiece W is moved relative to the focal position of the optical system of the optical device body. You may raise / lower a main body or its one part. FIG. 10 illustrates a lift mechanism (corresponding to the objective lens moving means of the present invention) 90 that lifts and lowers the objective lens 39. With such a configuration, it is only necessary to move up and down relatively small parts (objective lenses), so that the lifting mechanism 90 can be reduced in size and weight.

  (3) In the first embodiment, the light receiving pinhole array 55 is provided with the microlens 57, and in the second embodiment, instead of this, the single converging lens 75 is provided. The converging lens 75) may be eliminated. In this case, since the light passing through the light receiving pinhole 56 is diverged and travels toward the image sensor 51, the light receiving spot formed on the imaging surface 51A is increased. Therefore, when the converging means is abolished, it is preferable to arrange the image sensor 51 in a state as close as possible to the light receiving pinhole array 55, thereby making it possible to reduce the light receiving spot.

  (4) In the first embodiment, the mounting table 15 is stopped at predetermined intervals, and the workpiece W is scanned with light in this state. However, the scanning speed (slider 63) is higher than the moving speed of the mounting table 15. (Moving speed) of the head is sufficiently high, it is possible to perform scanning while the mounting table 15 is moved.

  (5) In the third embodiment, the example in which the shape of the workpiece W is measured using an area where the speed of the slider 63 is stable has been described. However, the speed of the slider 63 is not necessarily the same over the entire range of the scanning area. There is no need, and the following configuration may be used. That is, the shape measurement of the workpiece W is performed by stopping the mounting table 15 at predetermined intervals and irradiating (scanning) light to the measurement area of the workpiece W each time, but the conditions are different between different scanning points. However, it is only necessary that the same scanning point be irradiated with light under the same conditions (same time and same light amount) for each scan.

  (6) In the above embodiment, the collimator lens 38 is provided between the beam splitter 46 and the objective lens 39. However, the collimator mens 38 may be eliminated.

The figure which shows the whole structure of the optical measuring device in Embodiment 1. Diagram showing light receiving pinhole arrangement Diagram showing the state where both arrays have moved horizontally Enlarged view of light receiving pinhole array The figure which shows the state in which the several light was radiate | emitted from the light projection part. The figure which shows the whole structure of the optical measuring device in Embodiment 2. Explanatory drawing of Embodiment 3 (a) The figure which shows the mode of the change of the moving speed of a slider (b) The figure which shows the moving stroke of a slider The figure which shows the arrangement | sequence of the light projection pinhole in Embodiment 4 The figure which shows the state which applied the light projection element array to the light projection part The figure which shows the other example (structure which raises / lowers an objective lens) of the raising / lowering mechanism Figure showing a conventional example

Explanation of symbols

10: Elevating mechanism (relative movement means)
15 ... Placement table 20 ... Processing section (shape determining means)
DESCRIPTION OF SYMBOLS 30 ... Optical apparatus main body 31 ... Light projection part 35 ... Light projection pinhole array 39 ... Objective lens 46 ... Beam splitter (light branching means)
51 ... Image sensor (imaging means)
55. Light receiving pinhole array

Claims (7)

An optical device main body for condensing the light emitted from the light projecting source so as to focus on the object to be measured, imaging the reflected light, and outputting an imaging signal;
A mounting table on which the measurement object is mounted;
A relative movement means for moving the measurement object relative to the optical system of the optical device body by moving at least one of the optical device body or the mounting table in the optical axis direction of light;
A shape determination unit that determines a shape of a measurement object based on an imaging signal at each time point that is relatively moved by the relative movement unit, and an optical measurement device comprising:
The optical device body includes:
Projecting means having a plurality of the projecting light sources arranged periodically with a predetermined interval;
An objective lens for condensing each outgoing light emitted from each of the plurality of light projecting light sources on a measurement object;
A light branching unit that branches the reflected light reflected by the measurement object and then passed through the objective lens in a direction different from the light projecting unit;
A light receiving pinhole array disposed at a position optically conjugate with the light projecting means;
Light reception that opens on the light receiving pinhole array at the same interval as the arrangement interval of the light projecting light sources or at a similar interval, and individually passes the reflected lights branched by the light branching means while being converged by the objective lens. Pinholes,
An imaging surface having an imaging surface on which each reflected light that has passed through the light receiving pinhole is incident, and an imaging means capable of outputting the imaging signal according to the amount of the incident light.
The light projecting means and the light receiving pinhole array are arranged so that an output optical axis of the light projecting means and an axis of the light receiving pinhole are parallel to each other, and are integrated in a direction orthogonal to the output optical axis. And an optical scanning mechanism that allows the light from the light projecting light source to be optically scanned on the object to be measured. The optical measurement apparatus according to claim 1, further comprising a converging unit that causes the reflected light that has passed through the light receiving pinhole to converge on the imaging surface. The converging means comprises a converging lens group consisting of a collection of converging lenses provided individually for each light receiving pinhole, and the converging lens group is integrated with the light receiving pinhole array. The optical measuring device according to claim 2. The converging means is between the light receiving pinhole array and the imaging means, and has a single converging lens having a size over the entire length of the optical path of the total reflected light that has passed through each of the light receiving pinholes. The optical measuring device according to claim 2, wherein The shape determining means is configured to detect the measurement object based on an imaging signal of light incident on the imaging means after a predetermined time or more has elapsed since the integral movement of the light projecting means and the light receiving pinhole array is started. 5. The optical measuring device according to claim 1, wherein the shape is determined. 6. The optical measurement apparatus according to claim 1, wherein the relative moving unit includes an objective lens moving unit that moves the objective lens in the optical axis direction. The optical projector according to any one of claims 1 to 6, wherein the light projecting unit includes a light projecting element array in which a plurality of light projecting elements are periodically arranged on a support member at a predetermined interval. measuring device.

Images