JP2009014495A - Measuring device and measuring method using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance measuring accuracy by obtaining sharp projection image where color bleeding is suppressed without using white powder even for measured objects being translucent. <P>SOLUTION: A measuring device includes: a light projecting means for projecting light to a measured object; an image capturing means for capturing the image of projection image by the light; a first detecting means for detecting the maximum luminance and the maximum luminance position in the image-captured projection image; a setting means for setting a separation distance position separated by a predetermined distance from the maximum luminance position in the projection image; a second detecting means for detecting the luminance at the separated position; and a processing means for processing luminance maximization to maximize the luminance difference between the maximum luminance and the luminance at the separated position. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a measurement apparatus that performs measurement by projecting slit light or the like onto an object to be measured, and particularly relates to a measurement apparatus in which the amount of projected light is variable and a measurement method using the same.

  2. Description of the Related Art Conventionally, a measuring device such as a three-dimensional shape measuring instrument that includes a light projecting unit and performs measurement by projecting (projecting) a light beam such as slit light or a light beam onto an object to be measured 900 is known. In this measuring apparatus, for example, a linear projection image 901 shown in FIG. 20A is projected on the surface of the object to be measured. For example, when the object 900 is a translucent member such as a translucent ceramic, the actual projected image is, for example, as shown in FIG. As a result, the peripheral portion of the original projection image (projected projection image, which will be described later) 901 blurs as if blurred (this is expressed as “brightness” (or light bleed)). This will be described with reference to the drawings. The luminance distribution 911 shown in FIG. 21A corresponds to the projected image 901 in FIG. 20A, and when the projected image 901 is blurred, FIG. As shown in b), a luminance distribution 912 is formed by overlapping the original luminance distribution 911, and the width of the predetermined luminance value is wide. In particular, in the case where the light beam is obliquely incident on the object to be measured, such as the above three-dimensional shape measuring instrument using the light cutting method, the side opposite to the light incident side with respect to the projection image 901 is used. The degree of blurring at the position of is greater. Due to such blurring, an accurate projection image 901 cannot be obtained, and the measurement accuracy of the object to be measured is lowered.

Regarding prevention of such a decrease in measurement accuracy, for example, Patent Document 1 discloses that a light source output control unit is used to adjust a light projection amount, that is, a total light reception amount detected by a light receiving unit is substantially constant. A technique for controlling the output is disclosed. For example, Patent Document 2 discloses a technique for adjusting the amount of received light, that is, making the shutter speed (exposure time) of the CCD camera variable.
JP-A-8-145625 JP-A-6-147850

  However, the above technique simply adjusts the amount of light emitted or received, and does not handle the blurring in the projection image directly in association with the adjustment. For this reason, for example, blurring has occurred, and if the projected light intensity is increased by the above technique to increase the brightness of the projected image in order to make the projected image clear, the amount of blurring also increases. Furthermore, if the brightness of the projected image is increased, the surface reflected light from the projected image is larger than the amount of blemishes (internal scattered light). Thereafter, only the brightness of the blurring portion increases. As a result, the brightness value of the originally projected image of surface reflection and the brightness value of the blur are close to each other, and on the contrary, there is a problem that the blur is increased rather than making the projected image clear. Conventionally, when the object to be measured is a translucent member, there is a method of clarifying the projected image by applying white powder (flaw detection material) or the like to this surface. The application | coating operation | work of this etc. is needed, and a cost and an effort will be taken. Moreover, the influence of the error which arises on a powder surface and an actual to-be-measured surface also generate | occur | produces by powder application | coating.

  The present invention has been made in view of the above circumstances, and even a light-transmitting object to be measured can obtain a sharp projected image with suppressed blurring without using white powder or the like. It is an object of the present invention to provide a measurement device capable of increasing measurement accuracy and a measurement method using the same.

  A measuring apparatus according to an embodiment of the present invention includes a light projecting unit that projects a light beam onto an object to be measured, an image capturing unit that captures a projection image by the light beam, and a maximum luminance and a maximum luminance position in the captured projection image. First detection means for detecting; setting means for setting a separation position spaced apart from the maximum luminance position in the projection image by a predetermined distance; second detection means for detecting the luminance at the separation position; and the maximum luminance and the separation. And processing means for performing a brightness difference maximization process for maximizing a brightness difference from the brightness of the position.

  According to the above configuration, a light beam is projected onto the object to be measured by the light projecting unit, and a projected image by the light beam is captured by the imaging unit. The maximum brightness and the maximum brightness position in the captured projection image are detected by the first detection means, and a separation position that is separated from the maximum brightness position in the projection image by a predetermined distance is set by the setting means. Then, the brightness at the separated position is detected by the second detection means, and the brightness difference maximization process for maximizing the brightness difference between the maximum brightness and the brightness at the separated position is performed by the processing means.

  In this way, the brightness difference maximization process is performed so that the brightness difference between the maximum brightness in the projected image and the brightness at the separated position (brightness brightness) is maximized, so the maximum brightness that is the brightness that represents the original projected image. On the other hand, it is possible to relatively reduce the luminance level of the spot where the blur other than the maximum luminance occurs, that is, to clarify the difference in luminance between the original projected image and the blur image. As a result, even if the object to be measured has translucency, it is possible to obtain a clear projected image in which blurring is suppressed (original projected image stands out) without using white powder. Accuracy can be increased.

  Further, in the above configuration, the processing means includes an adjusting means for adjusting a light output by the light projecting means, and the adjustment is performed so that the luminance difference is maximized as the luminance difference maximization processing. The light output may be adjusted by means (claim 2).

  According to this, the processing means is provided with an adjusting means for adjusting the light output by the light projecting means. By this processing means, the adjusting means causes the brightness difference to be maximized as the brightness difference maximization processing. Since the light output is adjusted, the brightness difference maximization process can be easily realized by a simple method of adjusting the light output.

  Further, in the above configuration, the processing unit determines whether or not a maximum luminance value in the projection image exceeds a maximum sensitivity value of the imaging unit, and an adjustment unit that adjusts a light output by the light projecting unit. A discriminating unit, and a truncation unit for performing a truncation operation for cutting pixel data having a luminance equal to or lower than a predetermined threshold in the projection image, and the adjustment unit as the luminance difference maximization process, The light output is adjusted so that the maximum luminance value is highest in a range not exceeding the sensitivity maximum value determined by the determination, and the threshold is set according to the luminance at the separated position by the cutoff means, The cut-off operation may be performed based on a threshold value (Claim 3).

  According to this, the processing means adjusts the light output by the light projecting means, the determining means for determining whether the maximum luminance value in the projected image does not exceed the maximum sensitivity value of the imaging means, the projection And a cut-off means for performing a cut-off operation for cutting pixel data having a luminance equal to or lower than a predetermined threshold in the image, and as a luminance difference maximization process, the adjustment means sets the maximum luminance value to the sensitivity determined by the determination. The light beam output is adjusted so as to be the highest in a range not exceeding the maximum value, and a threshold is set according to the luminance at the separated position by the cutoff means, and a cutoff operation is performed based on the threshold.

  In this way, the brightness difference maximization process is set according to the brightness (brightness brightness) of the separated position by adjusting the light output so that the maximum brightness value becomes the highest within the range not exceeding the sensitivity maximum value of the imaging means. Based on the threshold value, it can be easily realized by a simple method of cutting (cutting) an image (pixel data) of a so-called low luminance level below the threshold value in the projected image. Further, since the threshold value or less can be cut off, even if the luminance distribution is an asymmetric projection image obtained when, for example, a light beam is incident obliquely on the object to be measured, The luminance centroid can be easily brought close to the luminance centroid of the original projected image, and the influence of blurring on the luminance centroid can be reduced. As a result, for example, the luminance center of gravity calculation using the luminance distribution can be performed more accurately, and as a result, the measurement accuracy can be improved.

  In the above configuration, the cut-off means may set the threshold value to a value that is equal to or greater than the luminance at the separated position and less than the maximum luminance value.

  According to this, since the threshold is set to a value that is greater than or equal to the luminance at the separated position and less than the maximum luminance value by the cut-off means, it is possible to reduce the influence of the blur component on the slit image detection due to the cut-off. it can. In other words, by cutting out the blur that is a noise component, the contour of the slit image can be clearly captured, and the luminance gravity center position can be accurately obtained.

  In the above configuration, the cut-off means may set the threshold value to a luminance value at the separated position.

  According to this, since the threshold value is set to the brightness value of the separated position by the cut-off means, it is easy to set the threshold value according to the brightness of the separated position by using the brightness itself of the separated position as the threshold value. Will be able to do.

  In the above configuration, the setting unit may set the separation position separated from the maximum luminance position by a predetermined distance in a direction opposite to the light incident side with respect to the object to be measured (Claim 6).

  According to this, since the setting means sets a separation position that is separated from the maximum luminance position by a predetermined distance in the direction opposite to the light incident side with respect to the object to be measured, the light ray is incident on the object to be measured from an oblique direction, that is, a predetermined incident. Even in the case of projection at a corner, it is possible to set a separation position (a position in the direction opposite to the incident side of the light beam) that can suppress blurring more, and thus, regardless of the incident angle of the light beam. Measurement accuracy can be improved by suppressing blurring.

  Further, in the above configuration, the apparatus further comprises storage means for storing set position information, which is information of various separation positions set corresponding to various objects to be measured, and the setting means is based on the set position information. You may set the said separation position for every measured object (Claim 7).

  According to this, the storage means stores the set position information, which is information of various separation positions set corresponding to the various measured objects, and the setting means stores each measured object based on the set position information. Thus, it is possible to effectively suppress blurring for each object to be measured.

  In the above configuration, the storage unit further stores the set position information according to various incident angles of the light beam with respect to the object to be measured, and the setting unit is configured to determine the incident angle based on the set position information. The separation position may be set according to (Claim 8).

  According to this, the storage unit stores setting position information corresponding to various incident angles of the light beam to the object to be measured, and the setting unit sets a separation position corresponding to the incident angle based on the setting position information. Therefore, it is possible to effectively suppress blurring for each incident angle.

  In addition, the measurement method according to the embodiment of the present invention includes a light projecting step of projecting a light beam on the object to be measured, an image capturing step of capturing a projection image by the light beam, and a maximum luminance and a maximum luminance in the captured projection image. A first detection step for detecting a position, a setting step for setting a separation position spaced apart from the maximum luminance position in the projection image by a predetermined distance, a second detection step for detecting the luminance at the separation position, and the maximum luminance. And a processing step of performing a brightness difference maximization process for maximizing a brightness difference from the brightness at the separated position.

  According to the said structure, a light ray is projected on a to-be-measured object in a light projection process, and the projection image by a light ray is imaged in an imaging process. In the first detection step, the maximum luminance and the maximum luminance position in the captured projection image are detected, and in the setting step, a separation position that is separated from the maximum luminance position in the projection image by a predetermined distance is set. Then, the brightness at the separated position is detected in the second detection step, and the brightness difference maximization process for maximizing the brightness difference between the maximum brightness and the brightness at the separated position is performed in the processing step.

  In this way, the brightness difference maximization process is performed so that the brightness difference between the maximum brightness in the projected image and the brightness at the separated position (brightness brightness) is maximized, so the brightness is representative of the original projected image without blurring. It is possible to relatively reduce the brightness level of a spot where a blur other than the maximum brightness occurs with respect to a certain maximum brightness, that is, to clarify the difference in brightness between the original projected image and the blur image. it can. As a result, even if the object to be measured has translucency, it is possible to obtain a clear projected image in which blurring is suppressed (original projected image stands out) without using white powder. Accuracy can be increased.

  Further, in the above configuration, the processing step includes an adjustment step of adjusting light output by the light projecting step, and the adjustment step is performed so that the luminance difference is maximized as the luminance difference maximization processing. May be a step of adjusting the light output.

  According to this, the processing step has an adjustment step of adjusting the light output by the light projection step, and in this processing step, as the luminance difference maximization processing, the light beam is adjusted by the adjustment step so that the luminance difference is maximized. Since the output is adjusted, the luminance difference maximization process can be easily realized by a simple method of adjusting the light beam output.

  Further, in the above configuration, the processing step includes an adjustment step of adjusting a light output in the light projection step, and a determination for determining whether or not a maximum luminance value in the projection image exceeds a maximum sensitivity value in the imaging. And a step of performing a cut-off operation for cutting pixel data having a luminance equal to or lower than a predetermined threshold in the projected image, and the adjustment step includes the maximum step as the luminance difference maximization process. The light output is adjusted so that the luminance value becomes the highest in a range not exceeding the maximum sensitivity value determined by the determination, and the threshold value is set according to the luminance at the separated position in the cutoff step, and the threshold value is set to the threshold value. The cut-off calculation may be performed on the basis of this (claim 11).

  According to this, the processing step is an adjustment step of adjusting the light output in the light projection step, a determination step of determining whether or not the maximum luminance value in the projection image exceeds the maximum sensitivity value in the imaging, and the projection image In this processing step, the maximum luminance value is determined by the adjustment step as a luminance difference maximization process in the adjustment step. The light output is adjusted so as to be the highest within a range not exceeding the maximum value of sensitivity, and a threshold is set according to the brightness at the separated position by the cutoff process, and a cutoff operation is performed based on the threshold. .

  In this way, the brightness difference maximization processing is set according to the brightness (brightness brightness) of the separated position by adjusting the light beam output so that the maximum brightness value becomes the highest in a range not exceeding the sensitivity maximum value in imaging. Based on the threshold value, it can be easily realized by a simple method of cutting (cutting) an image (pixel data) of a so-called low luminance level below the threshold value in the projection image. Further, since the threshold value or less can be cut off, even if the luminance distribution is an asymmetric projection image obtained when, for example, a light beam is incident obliquely on the object to be measured, The luminance centroid can be easily brought close to the luminance centroid of the original projected image, and the influence of blurring on the luminance centroid can be reduced. As a result, for example, the luminance center of gravity calculation using the luminance distribution can be performed more accurately, and as a result, the measurement accuracy can be improved.

  According to the present invention, the luminance difference maximization process is performed so that the luminance difference between the maximum luminance in the projection image and the luminance at the separated position (brightness luminance) is maximized, and thus represents the original projection image without blurring. It is possible to relatively reduce the brightness level of the spot where the blurring other than the maximum brightness occurs with respect to the maximum brightness which is the brightness, that is, to clarify the difference in brightness between the original projected image and the blurring image. be able to. As a result, even if the object to be measured has translucency, it is possible to obtain a clear projected image in which blurring is suppressed (original projected image stands out) without using white powder. Accuracy can be increased.

(Embodiment 1)
1 is a perspective view showing a portable three-dimensional measuring apparatus 1 according to the first embodiment, FIG. 2 is a side view thereof, FIG. 3 is a perspective view showing a measurement region of the portable three-dimensional measuring apparatus 1, and FIG. These are perspective views which show the irradiation condition of the slit light S with respect to the to-be-measured object (measuring object) which has a three-dimensional shape as shown to the to-be-measured object 100, for example. The portable three-dimensional measuring apparatus 1 measures a three-dimensional shape of an object to be measured by a light cutting method, and includes a main body housing 10, slit light generating means 2 housed therein, and a light projecting optical system 3. The image pickup means 4 and the control unit 6 are included. The portable three-dimensional measuring apparatus 1 illustrated here has a rod shape having a size of a general caliper, and one end side is a measuring head unit H that projects and receives the slit light S, and the other side. The end side is a grip portion G for the user to grip.

  As shown in FIG. 1, the main body housing 10 is a housing in which a head housing portion 11 corresponding to the measurement head portion H, an intermediate housing portion 12, and a grip housing portion 13 corresponding to the grip portion G are integrated. . The head housing portion 11 has a rectangular cross section or a substantially rectangular parallelepiped shape, and a slit light generating means 2, a light projecting optical system 3, an imaging means 4 and the like which are measurement elements necessary for three-dimensional measurement are mounted therein. A control unit 6 that controls the operation of the measurement element is mounted inside the intermediate housing unit 12. The grip housing portion 13 has a cylindrical shape so that it can be easily held, and a power supply battery (not shown) is accommodated therein. In addition, the outer peripheral surface of the grip housing part 13 is subjected to a roughening process for preventing slipping.

  The slit light generating means 2 generates slit light S that spreads in a fan shape from the irradiation end for irradiating the object to be measured. The slit light generating means 2 includes a laser light source 21 made of, for example, a small laser light source, that is, for example, a small LD (Laser diode) that generates laser light having a visible wavelength (the light emitted from the laser light source 21 is slit light). Including an optical member (not shown) that converts the light into a slit). The optical member is made of, for example, a cylindrical lens, a cylindrical lens, or a slit plate. Further, the slit light generating means 2 is arranged so as to overlap the back side of the light receiving surface of the imaging means 4, which contributes to the downsizing of the size in the X direction in FIG. Yes.

  The light projecting optical system 3 is for irradiating the measured light (measured object 100) with the slit light S (slit light projecting optical system 31). That is, the light projecting optical system 3 bypasses the slit light S emitted from the slit light generating means 2 disposed on the back side of the light receiving surface of the imaging means 4 in the vicinity of the imaging means 4, and the front direction of the imaging means 4. It provides a detour optical path that is directed to The slit light projecting optical system 31 converts the laser light emitted from the laser light source 21 into a slit light S spreading in a fan shape, and irradiates the slit light S toward the object to be measured. The projected image is photographed together with the object to be measured by an imaging sensor 41 described later (the projected image by the slit light S is reflected in the photographed image). In the example shown in FIG. 1, the reflection surface R1 is emitted from the laser light source 21 in a substantially horizontal direction (X direction) and reflects the slit light in a substantially vertical downward direction (Z direction). The reflecting surface R2 reflects the slit light reflected by the reflecting surface R1 so as to be bent in an oblique direction.

  Further, the light projecting optical system 3 includes a reflective surface that reflects the slit light S, and at least one of the reflective surfaces is equivalent to the arrangement position of the light receiving surface of the imaging unit 4 when viewed from the measured object side. It is arranged at a position or a position farther than that. Here, the light projecting optical system 3 includes two reflecting surfaces R1 and R2, and the reflecting surface R1 is disposed at a position farther from the position where the light receiving surface of the imaging unit 4 is disposed.

  The imaging unit 4 (imaging unit) includes a two-dimensional imaging sensor (imaging sensor 41) such as a CCD (Charge coupled device) area sensor (the imaging unit 4 includes slit light S on the light receiving surface of the imaging sensor 41). In addition, a light receiving optical system (not shown) that forms an image of reflected light from the object to be measured is included), and an image (captured image) is obtained by imaging the object to be measured. The light receiving surface of the imaging means 4 is disposed so as to face the object to be measured. As a result, as shown in FIG. 2, the light receiving optical axis A2 of the image pickup means 4 extends right below (Z direction). On the other hand, the light projecting optical axis A1 of the slit light S extends downward with an inclination. That is, the light projecting optical axis A1 intersects the light receiving optical axis A2 at a predetermined crossing angle. In the light cutting method, such crossing of the optical axes is essential. In the example of this figure, the intersection of the light projecting optical axis A1 and the light receiving optical axis A2 is set to be the focal plane of the light projecting optical system and the light receiving optical system. Incidentally, FIG. 3 shows a measurement area (focal plane) which is an imaging area of the imaging means 4. In the example shown in FIG. 3, the measurement region is the bottom surface of a square pyramid whose apex is one point on the imaging surface of the imaging means 4.

  The control unit 6 includes a CPU (Central processing unit), various circuits, and the like, and controls the light emission operation of the slit light generation unit 2, the imaging operation of the imaging unit 4, and the like. Details of the control unit 6 will be described below with reference to FIG. FIG. 5 is a block diagram showing an electrical configuration of the portable three-dimensional measuring apparatus 1. The portable three-dimensional measuring apparatus 1 includes an external interface unit 7 in addition to the laser light source 21, the image sensor 41, and the control unit 6 described above.

  The external interface unit 7 is used to connect the portable three-dimensional measuring device 1 and an external device 8 such as a personal computer (PC) so as to allow data communication via a USB terminal or the like provided in the grip unit G or the like. Interface. The external device 8 includes a monitor unit 81 and the like, and is configured to display the captured image transmitted via the external interface unit 7. The user moves the portable three-dimensional measuring apparatus 1 (measuring head unit H) while viewing the so-called preview-displayed video (monitor image; photographed image) on the monitor unit 81 (measurement object 100). Can be taken. Note that the portable three-dimensional measuring apparatus 1 can start imaging by an instruction input from an operation unit (not illustrated) provided in the main body housing 10 or an operation unit of the external device 8, for example. Even after the operation is started, it is possible to display the preview as described above by switching to the preview mode, for example, by inputting an instruction.

  The control unit 6 includes a light emission control unit 61, a timing generator (TG) 62, an AD converter 63, a digital calculation processing unit 64, an image buffer frame memory 65, an image calculation frame memory 66, a projection image luminance calculation unit 67, and a CPU 68. It is configured to include. The light emission control unit 61 controls the light emission operation of the laser light source 21, and includes an LD drive circuit that causes the LD to perform laser oscillation.

  The TG 62 generates a predetermined timing pulse (vertical transfer pulse, horizontal transfer pulse, charge sweep pulse, etc.) based on the reference clock supplied from the CPU 68 and outputs it to the imaging sensor 41 to control the imaging operation of the imaging sensor 41. Further, the analog / digital conversion operation in the AD converter 63 is controlled by outputting a predetermined timing pulse to the AD converter 63. The AD converter 63 converts the analog R, G, B image signal output from the image sensor 41 into a digital image signal composed of a plurality of bits, for example, 12 bits, based on the timing pulse output from the TG 62. . The AD converter 63 includes a CDS (correlated double sampling) circuit, an AGC (auto gain control) circuit, a clamp circuit, and the like.

  The digital arithmetic processing unit 64 is composed of an FPGA (Field Programmable Gate Array) or the like, and performs predetermined signal processing on image data (pixel data) output from the AD converter 63 to create an image file. The circuit includes a circuit, a white balance control circuit, a gamma correction circuit, and the like. The projection image luminance calculation unit 67 performs calculation related to the luminance of the projection image (expressed as projection image luminance calculation) based on the information of the projection image captured by the imaging sensor 41. This projection image luminance calculation is processing performed as part of luminance difference maximization processing described later. Details will be described later.

  The image buffer frame memory 65 includes a RAM (Random Access Memory) or the like, and stores image (frame image) data captured by the image sensor 41. The image data taken into the digital arithmetic processing unit 64 is written into the image buffer frame memory 65 in synchronization with the reading of the image sensor 41. The image calculation frame memory 66 is composed of a RAM or the like, and is a calculation processing target taken out from the image buffer frame memory 65 at the time of the contrast calculation by the projection image luminance calculation unit 67 (or calculation processing by the digital calculation processing unit 64). (Image for calculation) is stored.

  The CPU 68 is a so-called central processing unit that controls the operation of each functional unit such as the light emission control unit 61, the TG 62, the digital calculation processing unit 64, and the projection image luminance calculation unit 67 in accordance with an operation signal given from the operation unit or the like. . In particular, in the present embodiment, the CPU 68 performs processing related to the luminance difference maximization processing together with the projection image luminance calculation unit 67 as described later. The CPU 68 also has a function of performing arithmetic processing for obtaining a three-dimensional shape of the measurement object as shown in the measurement object 100, for example, from the obtained projection image information.

  FIG. 6 is a block diagram of the brightness difference maximization processing of the projected image brightness calculation unit 67. The projected image luminance calculation unit 67 includes a maximum luminance detection unit 671, a position setting unit 672, a blurring luminance detection unit 673, a luminance difference determination unit 674, and a measurement target information storage unit 675. The maximum luminance detecting unit 671 projects a projected image when the slit light S is projected onto an object to be measured (for example, an object to be measured such as a translucent member) by the laser light source 21 (slit light projecting optical system 31). The maximum brightness and the maximum brightness position of the projected image in the captured image are detected from the captured image obtained by imaging in (1). Here, FIG. 7 shows the luminance distribution 201 (luminance characteristics; luminance profile) in the direction of the arrow A shown in FIG. 20B, that is, the incident surface direction (projection direction) of the slit light with respect to the surface of the object to be measured. An example is shown. However, the luminance distribution 204 indicated by a dotted line indicates the luminance distribution in the projected projection image. The maximum luminance detecting unit 671 detects the maximum luminance value in the luminance distribution 201 and the position where the maximum luminance value is obtained, that is, the position indicated by reference numeral 202 (maximum luminance position 202).

  The position setting unit 672 sets, for example, a position indicated by reference numeral 203 (separated position; a blur brightness position 203 described later) that is separated from the maximum brightness position 202 in the projection image by a predetermined distance X. At this separated position, as described above, blurring occurs in the peripheral portion of the original projected image 901 due to the influence of the surface state of the object to be measured or internal scattered light, but the position setting unit 672 Set the position where the blur is occurring. The brightness at the position where the blur is generated is expressed as “bright brightness”, and the position of the brightness is expressed as “bright brightness position” or “bright brightness detection position”. In addition, the “original projected image” is expressed as a “projected projected image” in the meaning of a projected image in which no blurring due to light projection, that is, the slit light itself occurs, and on the other hand, when blurring occurs The entire projected image including this projected projection image (projected image in which a blur is superimposed on the projected projection image) is expressed as a “blurred image” to distinguish them.

  The blur brightness detection unit 673 detects the brightness at the blur brightness position set by the position setting unit 672, that is, the blur brightness. The luminance difference determination unit 674 calculates the luminance difference (luminance difference D shown in FIG. 7) between the maximum luminance (maximum luminance value) detected by the maximum luminance detection unit 671 and the bleed luminance (brightness luminance value). It is determined whether or not the luminance difference is the maximum. The luminance difference determination unit 674 calculates the luminance difference every time the output of the laser light source 21 is changed as will be described later. For example, the first luminance difference calculated last time is compared with the second luminance difference calculated this time. Thus, the luminance difference when the change amount of the difference (positive difference) between the luminance differences when the first luminance difference is subtracted from the second luminance difference is determined to be the maximum luminance difference. .

  The measurement target information storage unit 675 stores information on various separation positions (various bleed luminance positions) set corresponding to various measurement targets (objects to be measured) (this is referred to as setting position information). There are various measurement objects. For example, depending on the degree of semi-transparency of the object to be measured, that is, the difference in light transmittance, the position defined as the blur brightness (the position where the blur brightness is set) also varies. For example, as shown in FIG. 8, if the position of the same luminance level 221 is to be set as the blurring luminance position, the measurement target A and the measurement target B have distances X1 and X2 from the maximum luminance position of the blurring luminance position, respectively. They are different from each other. The set position information is obtained by preliminarily determining a blurring brightness position (a distance from the maximum brightness position) that is different for each measurement target. However, it is not always necessary to set a different brightness position depending on the difference in the measurement target. In this case, the measurement target information storage unit 67 has set position information that becomes the same brightness brightness position regardless of the difference in the measurement target. It may be stored.

  Incidentally, as shown in FIG. 9, the slit light S actually enters the object to be measured from an oblique direction (at a predetermined incident angle), or the incident direction (light projection angle) is the surface of the object to be measured. However, the blurring is asymmetric as compared with the case of FIG. Reference numeral 303 denotes the penetration of the slit light S into the object to be measured, and reference numeral 304 denotes the internal confusion of the slit light S that has entered. That is, the degree of blurring of the projected image 301 (corresponding to the original projected image 901) on the side indicated by the reference numeral 302, that is, the direction opposite to the incident side of the slit light S is large, and is symmetrical to the blurring. There is no sex. In this case, the luminance distribution 201 (luminance distribution 204) described with reference to FIG. 7 is actually a luminance distribution 311 having a large blurring on the side indicated by reference numeral 302 in FIG. 9 as shown in FIG. In the present embodiment, since it is desired to suppress this blurring that would prevent accurate measurement, the blur brightness position is set on the side where the blurring degree is larger. Therefore, the position setting unit 672 sets (defines) a position that is separated from the maximum luminance position 312 in the projection image by a predetermined distance X in the direction opposite to the slit light S (light ray) incident side as the blurring luminance position 313. In this case, the set position information is information in which a position away from the maximum luminance position in the direction opposite to the incident side of the light beam is a blurring luminance position. Note that the present invention includes not only the case where the slit light is incident from an oblique direction but also the case where the slit light is incident from the vertical direction.

  The control unit 6 has such a configuration and performs a luminance difference maximization process. That is, based on the luminance information obtained from the image (projected image) captured by the image sensor 41, the control unit 6 maximizes the luminance difference between the maximum luminance at the maximum luminance position and the luminance at the bleeding position. The light output (light emission output) of the laser light source 21, that is, the amount of light emitted to the object to be measured is automatically changed (adjusted). Specifically, the CPU 68 receives the determination result information of the luminance difference by the projection image luminance calculation unit 67 (luminance difference determination unit 674), and drives the light source control unit 61 to drive the laser light source 21 to adjust the light projection amount. Let me control. When the CPU 68 receives the determination result indicating that the luminance difference is maximized, the CPU 68 stops the light emission control unit 61 from changing the light output from the laser light source 21 and determines the light projection amount.

  This means that, as shown in FIG. 11, the light projecting means projects light onto the measurement object, the light projection means receives the projected image, and the brightness difference information is fed back to the light projecting light amount varying means. It can be said that the projecting means is adjusted until the brightness difference becomes the maximum. In other words, while monitoring the brightness difference of the projected image by the light receiving means, finding the control value of the light projecting means that can obtain the light projection amount that maximizes the brightness difference. Note that the captured image obtained by the light receiving unit when the luminance difference becomes the maximum may be handled as a desired captured image in which blurring is suppressed. By such luminance difference maximization processing, for example, the luminance distribution 201 in FIG. 7 is changed to, for example, the luminance distribution 231 shown in FIG. 12, so that the luminance difference at the same separation distance X (brightness luminance position 203) is obtained. From the initial luminance difference D, the maximum luminance difference Dmax is obtained. Similarly, in the case of FIG. 10 in which the blur is asymmetrical, the light beam output, that is, the light projection amount of the laser light source 21 is automatically adjusted so as to obtain a luminance distribution in which the luminance difference D at the separation distance X is maximized.

  The adjustment of the amount of light emitted by the laser light source 21 in actuality may directly change the light emitting device of the laser light source 21, that is, the output (light emission intensity) of the LD, specifically voltage control or PWM (Pulse Width). Modulation) may be performed by changing the output of the LD. For example, the light amount may be changed using a light amount reducing member. That is, for example, as shown in FIG. 13A, an ND filter (a neutral density filter) having various filters having different light transmittances is used, and the ND filter is driven to rotate by, for example, the light emission control unit 61, so that the laser It may be realized by switching various filters that transmit the light emitted from the light source 21. Also, for example, as shown in FIG. 13B, it is realized by using a polarizing plate, specifically, for example, at least one of them. You may implement | achieve using a pair of linearly-polarizing plate which adjusts a polarization degree by rotating. Of course, these may be used in combination. In short, any configuration that can change the amount of emitted light is acceptable.

  FIG. 14 is a flowchart illustrating an example of a measurement operation performed by the portable three-dimensional measurement apparatus 1 according to the first embodiment. First, slit light is projected onto the object to be measured by the laser light source 21 (step S1), and the object to be measured on which the projection image is projected is photographed by the image sensor 41 (step S2). The maximum luminance and the maximum luminance position in the projected image obtained by the photographing are detected by the maximum luminance detecting unit 671 (step S3), and the position setting unit 672 sets a blurring luminance position separated by a predetermined distance X from the maximum luminance position. (Step S4). Then, the brightness luminance detection unit 673 detects the brightness brightness at the brightness level, and the brightness difference determination unit 674 calculates the brightness difference between the maximum brightness and the brightness brightness (step S5). While determining whether or not (NO in step S7), based on this determination information, the CPU 68 (light emission control unit 61) changes the output of the laser light source 21 to adjust the light projection amount (step S6). If it is determined that the luminance difference is the maximum (YES in step S7), the CPU 68 stops changing the output of the laser light source 21 and determines the output of the laser light source 21 at this time, that is, the light projection amount (step). S8). Then, the projected image when the light is projected with the determined output of the laser light source 21 (step S9) is taken by the image sensor 41 (step S10). As a result, a photographed image in which the brightness difference between the maximum brightness and the blurring brightness is the maximum, that is, a photographed image (projected image) in which the blurring is suppressed is obtained. As a result, measurement accuracy can be increased.

(Embodiment 2)
FIG. 15 is a block configuration diagram relating to the luminance difference maximization processing of the projection image luminance calculation unit 67a in the portable three-dimensional measuring apparatus 1a according to the second embodiment. The projected image luminance calculation unit 67a includes a maximum luminance detection unit 671a, a luminance determination unit 676, a position setting unit 672a, a blurring luminance detection unit 673a, a threshold calculation unit 677, a threshold storage unit 678, and a measurement target information storage unit 675a. . Similar to the maximum brightness detection unit 671, the maximum brightness detection unit 671a detects the maximum brightness and the maximum brightness position of the projection image obtained by the imaging of the imaging sensor 41. Also in this case, as shown in FIG. 16A, the maximum luminance and the maximum luminance position 402 are detected in the projection image having the luminance distribution 401.

  The brightness determination unit 676 determines whether or not the maximum brightness value in the projected image exceeds the maximum sensitivity of the image sensor 41. Here, the “sensitivity” of the image sensor 41 indicates the magnitude of the output value when the luminance when the measurement target (subject) is imaged is used as the input value, that is, the output level with respect to the input. "" Indicates a level at which the output of the image sensor 41 is saturated (the maximum value of the output level of the image sensor 41). In the present embodiment, the luminance determination unit 676 stores information on the maximum value of the sensitivity, and outputs the output value from the image sensor 41, that is, the luminance value of each pixel of the captured image (projected image) and the maximum sensitivity value. The determination is made by comparison.

  Similarly to the position setting unit 67, the position setting unit 672a is separated from the maximum luminance position 402 in the projection image by a predetermined distance X in the direction opposite to the incident side of the slit light S (light beam), as shown in FIG. The determined position is set (defined) as the blur brightness position 403. The blur brightness detection unit 673a detects the blur brightness at the blur brightness position set by the position setting unit 672a.

  The threshold value calculation unit 677 performs calculation using a threshold value, specifically, a predetermined threshold value, and performs a cut-off calculation for cutting pixel data having a luminance equal to or lower than the threshold value in the projection image. In this cut-off calculation, the threshold calculation unit 677 first sets the threshold corresponding to the blur brightness at the blur brightness position 403. This threshold value is set as a value that is greater than the blur brightness at the blur brightness position 403 and less than the maximum brightness value.

  This will be described with reference to FIG. 16A. First, the threshold value calculation unit 677 sets, for example, the luminance level indicated by reference numeral 404 as a threshold value (threshold line, threshold level), and truncates pixel data having a luminance equal to or lower than this threshold value (threshold value). Since the following low-intensity part is cut, it is also expressed as “low-intensity cut”). Specifically, a process of replacing the luminance value (each pixel value) equal to or lower than the threshold value indicated by reference numeral 405 in the projected image with a predetermined luminance value (here, zero value indicated by reference numeral 406) lower than the luminance value. I do. As shown in FIG. 16B, this threshold value may be set to the same brightness level as the blur brightness at the blur brightness position 403 indicated by reference numeral 407 (the blur brightness itself may be used as the threshold). In this case as well, the low luminance cut (foot cut) is performed by replacing the luminance value equal to or lower than the threshold with the zero value indicated by reference numeral 408. In any case, the threshold value is set in accordance with the blur brightness (bright brightness brightness level), that is, a value between the blur brightness and the maximum brightness, or a value of the blur brightness itself. It can be said that the threshold value changes according to the brightness.

  The threshold storage unit 678 stores information on the threshold (low luminance cut threshold) used in the threshold calculation unit 677. This threshold value information may be information on a plurality of types of threshold values that are predetermined as corresponding to various blurring brightness values (for example, a look-up table that describes the relationship between the blurring brightness and the threshold value).

  Similar to the measurement target information storage unit 675, the measurement target information storage unit 675a stores information (set position information) of various separation positions (various blemishes luminance positions) set corresponding to various measurement targets. . Also in the present embodiment, the blur brightness position may be changed according to the measurement target.

  The control unit 6a of the portable three-dimensional measuring apparatus 1a has such a configuration and performs a luminance difference maximization process. That is, the control unit 6a is configured so that the maximum luminance at the maximum luminance position is the highest within a range not exceeding the sensitivity maximum value of the imaging sensor 41 based on luminance information obtained from a captured image (projected image) by the imaging sensor 41. In addition, the light output of the laser light source 21, that is, the amount of light emitted to the object to be measured is automatically changed (adjusted). Specifically, the CPU 68 of the control unit 6a receives the determination result information from the projection image luminance calculation unit 67a (luminance determination unit 676) and drives the light source control unit 61 to drive the laser light source 21 in order to adjust the light projection amount. Let me control. When the CPU 68 receives the determination result indicating that the maximum luminance value at the maximum luminance position is the maximum value within the range not exceeding the sensitivity maximum value, the CPU 68 causes the light emission control unit 61 to change the light output from the laser light source 21. Stop and confirm the light intensity.

  On the other hand, the control unit 6a sets the blur brightness position by the position setting unit 672a, and detects the blur brightness at this position by the blur brightness detection unit 673a. Then, the threshold value calculation unit 677 sets a threshold value according to the blur brightness at the blur brightness position, compares each pixel value of the projected image with this threshold value, and replaces the pixel value equal to or lower than the threshold value with a zero value. Perform foot cut (low brightness cut) with. As a result, for example, as shown in FIGS. 16A and 16B, the luminance difference between the maximum luminance and the bleed luminance at the same separation distance X (brightness luminance position 403) is changed from the initial luminance difference D to the luminance difference. It will spread to D1. Note that the point indicated by reference numeral 403 ′ in the drawing is a position separated by the same distance X from the maximum luminance position 402, but indicates that the luminance at this position has become zero by performing the cut-off process. Is. As described above, in the luminance difference maximization processing of the second embodiment, first, the maximum luminance value is set as large as possible within the sensitivity range of the image sensor 41, and in that state, the threshold value or less is cut off. Thus, the influence of the blur component on the slit image detection can be reduced. In other words, by cutting out the blur that is a noise component, the contour of the slit image can be clearly captured, and the luminance gravity center position can be accurately obtained.

  By the way, also in the case of this embodiment, as described with reference to FIGS. 9 and 10 above, the slit light S is actually incident on the object to be measured at a predetermined incident angle. The luminance distribution is also indicated by a luminance distribution 501. Also in this case, the position setting unit 672a causes the position where the degree of blurring in the projected image is larger, that is, the position separated from the maximum luminance position 502 by a predetermined distance X in the direction opposite to the slit light S (light ray) incident side. The brightness position 503 is set. The maximum luminance value is maximized within a range that does not exceed the sensitivity maximum value of the image sensor 41, and a threshold is set according to the blurring luminance at the blurring luminance position 503 (in FIG. 17, the luminance level at the blurring luminance position 503). The threshold value 504) is used to cut off pixel data below this threshold value in the same way as when the blurring is symmetric.

  When the bleed is asymmetric as described above, as shown in FIG. 17, the center of gravity (luminance centroid) position in the luminance distribution is an ideal in the case of an original projection image (projection projection image) without blemishes. Deviation occurs from the position (for example, the arrow position indicated by reference numeral 511) (for example, deviation to the arrow position indicated by reference numeral 512). For example, even when the projected image is shaped using the luminance centroid calculation method, the centroid position is shifted by the calculation. However, by cutting off the low luminance side by the cut off operation as in the present embodiment, the influence of blurring on the luminance centroid is reduced, and the luminance centroid position of the original projected image (for example, the arrow position indicated by reference numeral 513) is reduced. Get closer.

  As shown in FIG. 18, the brightness difference maximization processing of the present embodiment is performed by projecting light onto a measurement object by a light projecting unit and receiving a projection image by the light projecting by the light receiving unit. Projection image when the maximum brightness value is maximized while feedback to the light intensity variable means is performed to control the light intensity so that the brightness value is maximized within the range not exceeding the sensitivity maximum value of the light receiving means. Each pixel value is compared with a threshold value (read out from the threshold value storage means) set according to the brightness level (by the comparison means), and the pixel value with low brightness is cut off, so that the so-called original photographed image can be obtained. It can be said that it is a correction. This corrected photographed image may be handled as a desired photographed image with reduced blurring.

  FIG. 19 is a flowchart illustrating an example of a measurement operation performed by the portable three-dimensional measurement apparatus 1a according to the second embodiment. First, slit light is projected onto the object to be measured by the laser light source 21 (step S21), and the object to be measured on which the projection image is projected is photographed by the image sensor 41 (step S22). The maximum luminance value in the projected image obtained by the photographing is detected by the maximum luminance detecting unit 671a (step S23), and whether or not the maximum luminance value exceeds the maximum sensitivity of the image sensor 41 by the luminance determining unit 676. While determining (NO in step S24), the CPU 68 (light emission control unit 61) adjusts the light projection amount by changing the output of the laser light source 21 based on the determination information (step S25). When it is determined that the maximum luminance value is the maximum value within the range of the sensitivity maximum value (YES in step S24), the CPU 68 stops changing the output of the laser light source 21, and the laser light source 21 at this time This is determined by the output, that is, the amount of light emitted. Then, a projected image when projected with the determined output of the laser light source 21 is photographed by the imaging sensor 41 (step S26), and the maximum luminance position in the photographed projected image is detected by the maximum luminance detecting unit 671a (step S27). ). Next, the position setting unit 672a sets a blur brightness position that is a predetermined distance X away from the detected maximum brightness position (step S28), and the blur brightness detection unit 673a detects the blur brightness at this position (step S28). S29). Then, the threshold value calculation unit 677 sets a threshold value corresponding to the detected blur brightness (step S30), and performs a cut-off calculation for pixel data with low luminance equal to or less than this threshold value (step S31). As a result, a photographed image in which the brightness difference between the maximum brightness and the blurring brightness is maximum, that is, a photographed image (projected image) in which the blurring is suppressed is obtained.

  In addition, this invention can also take the following aspect. In each of the above-described embodiments, the description has been made on the assumption that the incident angle of the slit light S with respect to the object to be measured is constant, but actually, since it is a portable three-dimensional measuring device 1a (hand-held measuring device). The input angle can also change. If the incident angle is different, the state of the blur (the position and the degree of the blur) can be different, so the distance X from the maximum brightness position, that is, the position of the blur brightness can be determined according to the incident angle). desirable. Accordingly, set position information corresponding to various incident angles of the slit light S (light beam) with respect to the object to be measured is stored in the measurement target information storage unit 675 (675a), and the incident angle is set by the position setting unit 672 (672a). It is good also as a structure which sets the blurring brightness position based on different setting position information for every. However, as a method of determining the incident angle, for example, the portable three-dimensional measuring apparatus 1a may be provided with a gyro sensor or the like, and the incident angle may be determined based on posture detection information by the sensor. Alternatively, when the portable three-dimensional measuring apparatus 1a has a function of changing the emission angle of the slit light S by, for example, an input button, the determination may be made based on the switching information. In general, as the incident angle (degree of oblique incidence) increases, the symmetry of the luminance distribution is lost, and the deviation of the luminance gravity center position increases. Therefore, it is also possible to perform the blur brightness position setting such that the separation distance X becomes shorter as the incident angle is larger.

  As described above, according to the measuring apparatus (portable three-dimensional measuring apparatus 1, 1 a) according to the first and second embodiments of the present invention, light is emitted to the object to be measured by the light projecting means (laser light source 21). The projected image is projected, and a projection image by the light beam (slit light S) is captured by the imaging means (imaging sensor 41). The maximum brightness and the maximum brightness position in the captured projection image are detected by the first detection means (maximum brightness detection units 671 and 671a), and a separated position (smearing brightness position) separated from the maximum brightness position in the projection image by a predetermined distance. It is set by setting means (position setting units 672 and 672a). The second detection means (brightness brightness detection units 673 and 673a) detects the brightness at the separation position (brightness brightness), and the processing means (control units 6 and 6a) detects the difference in brightness between the maximum brightness and the brightness at the separation position. A luminance difference maximization process is performed to maximize the luminance difference.

  In this way, the brightness difference maximization process is performed so that the brightness difference between the maximum brightness in the projected image and the brightness at the separated position (brightness brightness) is maximized, so the brightness is representative of the original projected image without blurring. It is possible to relatively reduce the luminance level of a spot where a blur other than the maximum brightness occurs with respect to a certain maximum brightness, that is, between the original projected image (projected projected images 301 and 901) and the blurred image. The difference in brightness can be clarified. As a result, even if the object to be measured has translucency, it is possible to obtain a clear projected image in which blurring is suppressed (original projected image stands out) without using white powder. Accuracy can be increased.

  Further, the processing means is provided with an adjusting means for adjusting the light output by the light projecting means. By this processing means, the light output is adjusted by the adjusting means so that the brightness difference is maximized as the brightness difference maximization processing. Since the adjustment is performed, the luminance difference maximization process can be easily realized by a simple method of adjusting the light beam output.

  Further, the processing means adjusts the light beam output from the light projecting means, and the determining means for determining whether the maximum luminance value in the projected image does not exceed the maximum sensitivity value of the imaging means (luminance determining unit 676). And a cut-off means (threshold calculation unit 677) for performing a cut-off calculation for cutting pixel data having a luminance equal to or lower than a predetermined threshold in the projected image. The light output is adjusted so that the maximum luminance value becomes the highest in a range not exceeding the sensitivity maximum value determined by the determination, and a threshold is set according to the luminance at the separated position by the cutoff means, and based on the threshold. The cut-off operation is performed.

  In this way, the brightness difference maximization process is set according to the brightness (brightness brightness) of the separated position by adjusting the light output so that the maximum brightness value becomes the highest within the range not exceeding the sensitivity maximum value of the imaging means. Based on the threshold value, a so-called low brightness level image (pixel data) below the threshold value in the projected image is easily cut (cut) (see FIGS. 16A and 16B). Can be realized. Further, since the threshold value or less can be cut off, even if the luminance distribution (see FIG. 17) obtained when the light beam is incident obliquely on the object to be measured is an asymmetric projection image, for example. The luminance centroid of this luminance distribution can be easily brought close to the luminance centroid of the original projected image, and the influence of blurring on the luminance centroid can be reduced. As a result, for example, the luminance center of gravity calculation using the luminance distribution can be performed more accurately, and as a result, the measurement accuracy can be improved.

  Further, since the threshold is set to a value that is greater than or equal to the luminance at the separated position and less than the maximum luminance value by the cut-off means (see FIG. 16A), the effect of the blur component on the slit image detection due to the cut-off. Can be reduced. In other words, by cutting out the blur that is a noise component, the contour of the slit image can be clearly captured, and the luminance gravity center position can be accurately obtained.

  Further, since the threshold is set to the value of the luminance at the separated position by the cut-off means (see FIG. 16B), the setting of the threshold according to the luminance at the separated position sets the luminance at the separated position as the threshold value. This makes it easy to do.

  In addition, the setting means sets a separation position that is separated from the maximum luminance position by a predetermined distance in the direction opposite to the incident side of the light beam with respect to the object to be measured (see FIG. 17). Even when projected at an incident angle of 2 mm, it is possible to set a separation position (a position in the direction opposite to the incident side of the light beam) that can suppress blurring more, and thus to the incident angle of the light beam. Regardless of this, it is possible to suppress blurring and increase measurement accuracy.

  Also, the storage means stores set position information, which is information of various separation positions set corresponding to various objects to be measured, and the setting means determines the separation positions for each object to be measured based on the set position information. Since it is set, blurring can be effectively suppressed for each object to be measured.

  Further, the storage unit stores set position information corresponding to various incident angles of the light beam to the object to be measured, and the setting unit sets a separation position corresponding to the incident angle based on the set position information. It becomes possible to suppress blurring effectively for each angle.

  In addition, according to the measurement methods according to the first and second embodiments of the present invention, a light beam is projected onto the object to be measured in the light projecting step, and a projected image by the light beam is captured in the imaging step. In the first detection step, the maximum luminance and the maximum luminance position in the captured projection image are detected, and in the setting step, a separation position (brightness luminance position) that is separated from the maximum luminance position in the projection image by a predetermined distance is set. The Then, the brightness at the separated position is detected in the second detection step, and the brightness difference maximization process for maximizing the brightness difference between the maximum brightness and the brightness at the separated position is performed in the processing step.

  In this way, the brightness difference maximization process is performed so that the brightness difference between the maximum brightness in the projected image and the brightness at the separated position (brightness brightness) is maximized, so the brightness is representative of the original projected image without blurring. It is possible to relatively reduce the brightness level of a spot where a blur other than the maximum brightness occurs with respect to a certain maximum brightness, that is, to clarify the difference in brightness between the original projected image and the blur image. it can. As a result, even if the object to be measured has translucency, it is possible to obtain a clear projected image in which blurring is suppressed (original projected image stands out) without using white powder. Accuracy can be increased.

  Further, the processing step has an adjustment step of adjusting the light output by the light projection step. In this processing step, the light output is adjusted by the adjustment step so that the luminance difference is maximized as the luminance difference maximization processing. Therefore, the luminance difference maximization processing can be easily realized by a simple method of adjusting the light beam output.

  Furthermore, the processing step includes an adjustment step for adjusting the light output in the light projection step, a determination step for determining whether or not the maximum luminance value in the projection image exceeds the maximum sensitivity value in imaging, and a predetermined threshold in the projection image In this processing step, as a luminance difference maximization process, the maximum luminance value is determined by the above-mentioned determination. The light output is adjusted so as to be the highest in a range not exceeding the value, and a threshold is set according to the luminance at the separated position by the cutoff process, and a cutoff operation is performed based on the threshold.

  In this way, the brightness difference maximization processing is set according to the brightness (brightness brightness) of the separated position by adjusting the light beam output so that the maximum brightness value becomes the highest in a range not exceeding the sensitivity maximum value in imaging. Based on the threshold value, it can be easily realized by a simple method of cutting (cutting) an image (pixel data) of a so-called low luminance level below the threshold value in the projection image. Further, since the threshold value or less can be cut off, even if the luminance distribution is an asymmetric projection image obtained when, for example, a light beam is incident obliquely on the object to be measured, The luminance centroid can be easily brought close to the luminance centroid of the original projected image, and the influence of blurring on the luminance centroid can be reduced. As a result, for example, the luminance center of gravity calculation using the luminance distribution can be performed more accurately, and as a result, the measurement accuracy can be improved.

It is a perspective view which shows the portable three-dimensional measuring apparatus which concerns on 1st Embodiment. It is a side view of the portable three-dimensional measuring apparatus shown in FIG. It is a perspective view which shows the measurement area | region of the portable three-dimensional measuring apparatus shown in FIG. It is a perspective view which shows the irradiation condition of the slit light S with respect to the to-be-measured object (measurement object) which has a three-dimensional shape. It is a block diagram which shows the electric constitution of the portable three-dimensional measuring apparatus shown in FIG. It is a block block diagram regarding the brightness | luminance difference maximization process of the projection image brightness | luminance calculating part in the portable three-dimensional measuring apparatus shown in FIG. It is a figure which shows an example of the luminance distribution in the incident surface direction of the slit light with respect to the to-be-measured object surface of a projection image. It is a luminance distribution diagram for demonstrating the difference in the setting position by a measurement object (measurement object) differing. It is a perspective view for demonstrating a blurring state when slit light injects with respect to a to-be-measured object with a predetermined incident angle. It is a figure which shows an example of the luminance distribution of a projection image when slit light injects with respect to a to-be-measured object with a predetermined incident angle. It is a schematic diagram for demonstrating notionally the brightness | luminance difference maximization process in 1st Embodiment. It is a figure which shows an example of the luminance distribution of the projection image after the luminance difference maximization process with respect to the luminance distribution shown in FIG. It is a schematic diagram for demonstrating an example for adjusting the light emission amount by a laser light source, Comprising: (a) is a ND filter, (b) is a figure which shows a polarizing plate. It is a flowchart which shows an example of the measurement operation | movement by the portable three-dimensional measuring apparatus in 1st Embodiment. It is a block block diagram regarding the brightness | luminance difference maximization process of the projection image brightness | luminance calculating part in the portable three-dimensional measuring apparatus which concerns on 2nd Embodiment. It is a figure which shows an example of the brightness distribution of the projection image for demonstrating the brightness | luminance difference maximization process in 2nd Embodiment, Comprising: (a) sets a threshold value to the brightness level higher than a blurring brightness and less than a maximum brightness. (B) is a figure which shows the case where a threshold value is set to the level of a blurring brightness. It is a figure for demonstrating the setting of a threshold value, the difference in a brightness | luminance gravity center position, etc. in the asymmetrical brightness distribution in case slit light injects into a to-be-measured object diagonally. It is a schematic diagram for demonstrating notionally the brightness | luminance difference maximization process in 2nd Embodiment. It is a flowchart which shows an example of the measurement operation | movement by the portable three-dimensional measuring apparatus in 2nd Embodiment. It is a perspective view for demonstrating the projection image (original projection image and blemishes) of the to-be-measured object surface. It is a figure which shows an example of the luminance distribution of the projection image shown in FIG.

Explanation of symbols

1, 1a Portable three-dimensional measuring device (measuring device)
21 Laser light source (light projection means)
41 Imaging sensor (imaging means)
6, 6a Control unit (processing means)
61 Light emission control unit (adjustment means)
67, 67a Projected image luminance calculation unit 671, 671a Maximum luminance detection unit (first detection means)
672, 672a Position setting unit (setting means)
673, 673a Brightness luminance detection unit (second detection means)
674 Luminance difference determination unit 675, 675a Measurement object information storage unit 676 Brightness determination unit (discrimination means)
677 Threshold value calculation unit (cutting off means)
678 Threshold value storage unit 68 CPU
201, 231, 311, 401, 501, 911, 912 Luminance distribution 202, 312, 402, 502 Maximum luminance position 203, 313, 403, 403 ', 503
301 Projection Projection Image 404, 407, 504 Threshold 901 Original Projection Image X Separation Distance D Luminance Difference D1 Luminance Difference Dmax Luminance Difference S Slit Light (Ray)
100, 900 DUT

Claims (11)

A light projecting means for projecting a light beam onto the object to be measured;
An image pickup means for picking up a projected image by the light beam;
First detection means for detecting a maximum brightness and a maximum brightness position in the captured projection image;
Setting means for setting a separation position that is a predetermined distance away from the maximum luminance position in the projection image;
Second detection means for detecting the luminance of the separated position;
A measuring apparatus comprising: processing means for performing brightness difference maximization processing for maximizing a brightness difference between the maximum brightness and the brightness at the separated position. The processing means includes
It comprises an adjusting means for adjusting the light output by the light projecting means,
The measurement apparatus according to claim 1, wherein, as the luminance difference maximization processing, the light output is adjusted by the adjusting unit so that the luminance difference becomes maximum. The processing means includes
Adjusting means for adjusting light output by the light projecting means;
A discriminating means for discriminating whether or not a maximum luminance value in the projected image exceeds a maximum value of sensitivity of the imaging means;
A cut-off means for performing a cut-off operation for cutting pixel data having a luminance equal to or lower than a predetermined threshold in the projected image,
As the brightness difference maximization process,
The adjustment means adjusts the light output so that the maximum brightness value is highest in a range not exceeding the maximum sensitivity value determined by the determination, and the threshold means determines the threshold according to the brightness of the separation position. The measurement apparatus according to claim 1, wherein the cut-off calculation is performed based on the threshold value. The cutting means is
The measurement apparatus according to claim 3, wherein the threshold is set to a value that is greater than or equal to the luminance at the separated position and less than the maximum luminance value. The cutting means is
The measurement apparatus according to claim 3, wherein the threshold value is set to a luminance value at the separated position. The setting means includes
5. The measuring apparatus according to claim 3, wherein the separation position is set apart from the maximum luminance position by a predetermined distance in a direction opposite to the light incident side with respect to the object to be measured. Storage means for storing set position information, which is information of various separation positions set corresponding to various objects to be measured;
The setting means includes
The measurement apparatus according to claim 1, wherein the separation position for each object to be measured is set based on the set position information. The storage means
Further storing the set position information according to various incident angles of the light beam to the object to be measured;
The setting means includes
The measurement apparatus according to claim 1, wherein the separation position corresponding to the incident angle is set based on the set position information. A light projecting process for projecting light rays onto the object to be measured;
An imaging step of capturing a projected image by the light rays;
A first detection step of detecting a maximum brightness and a maximum brightness position in the captured projection image;
A setting step of setting a separation position that is a predetermined distance away from the maximum luminance position in the projection image;
A second detection step of detecting the brightness of the separated position;
And a processing step of performing a brightness difference maximization process for maximizing a brightness difference between the maximum brightness and the brightness at the separated position. The processing step includes
It has an adjustment step of adjusting the light output by the light projection step,
The measurement method according to claim 9, wherein the luminance difference maximization processing is a step of adjusting the light output by the adjustment step so that the luminance difference is maximized. The processing step includes
An adjusting step of adjusting the light output in the light projecting step;
A determination step of determining whether the maximum luminance value in the projected image does not exceed the maximum value of sensitivity in the imaging;
A step of performing a cut-off operation for cutting pixel data having a luminance equal to or lower than a predetermined threshold in the projected image,
As the brightness difference maximization process,
In the adjusting step, the light output is adjusted so that the maximum luminance value is highest in a range not exceeding the sensitivity maximum value determined by the determination, and in the cutoff step, the threshold value is set according to the luminance at the separation position. The measurement method according to claim 9, wherein the cut-off calculation is performed based on the threshold value.