JPH11281335A - Three-dimensional measuring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a three-dimensional measuring device for inputting both a distance image (an image for measuring a distance) and a color image (an image for display) by a single sensor. SOLUTION: A three-dimensional measuring device is provided with an IR cut filter 80a, a band-pass filter 80b, and a single color CCD sensor 53a. At the time of photographing a color image, the IR cut filter 80a is selected by a filter switching mechanism 81a, and at the time of photographing a distance image, the band-pass filter 80b is selected. Thus, both the color image and the distance image can be image picked-up by the single color CCD sensor 53a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-dimensional measuring device, and more particularly, to a so-called active type three-dimensional measuring device which irradiates a measuring object with reference light and receives reflected light to acquire three-dimensional data. The present invention relates to a dimension measurement device.

[0002]

2. Description of the Related Art Conventionally, there has been known a so-called active type three-dimensional measuring apparatus which projects three-dimensional data by projecting a reference beam onto an object to be measured and receiving the reflected beam. In such an active type three-dimensional measuring apparatus, a distance image (an image for measuring a distance and an image for calculating a three-dimensional shape of a measurement object) is provided.
2. Description of the Related Art There is known a device capable of inputting both an image and a color image (image for displaying a measurement object) (for example, Japanese Patent Application Laid-Open No. Hei 9-145319).

FIG. 19 shows such an active type 3
It is a block diagram showing composition of a dimension measurement device.

Referring to FIG. 1, a beam splitter (spectral prism) 52 includes a color separation film (a dichroic mirror) 52.
1. Two prisms 522, 52 sandwiching color separation film 521
3. Range image C provided on the exit surface of prism 522
It comprises a CD sensor 53 and a color image CCD sensor 54 provided on the exit surface of the prism 523.

An object to be measured is scanned by a semiconductor laser serving as reference light, and reflected light from the object to be measured is received by a light receiving lens 5.
1a.

The light incident from the light receiving lens 51a passes through the prism 522 and enters the color separation film 521. Light U0 in the oscillation band of the semiconductor laser is reflected by the color separation film 521 and then emitted toward the range image CCD sensor 53.

On the other hand, the light C0 transmitted through the color separation film 521
Is emitted toward the color image CCD sensor 54 through the prism 523.

The distance image CCD sensor 53 is driven by a distance image CCD driver 204. The color image CCD sensor 54 includes the color image CCD driver 2.
03.

The output of the range image CCD sensor 53 is A
After being processed by the / D converter (output processing circuit) 202, it is stored in the distance image frame memory 206. The output of the color image CCD sensor 54 is stored in a color image frame memory 205 after being processed by an A / D converter (output processing circuit) 201.

[0010]

As described above, in the conventional active-type three-dimensional measuring apparatus, two CCD sensors 53 and 54 are used, so that there are the following problems.

(1) In order to prevent a displacement between the distance image and the color image, it is necessary to finely adjust the mounting positions of the two CCD sensors.

(2) Since near-infrared light is mainly used as the reference light, it is necessary to manufacture a prism capable of separating near-infrared light for a distance image and visible light for a color image.

(3) The image quality of the color image depends on the spectral characteristics of the prism. The present invention has been made to solve the above problems, and has as its object to solve the problems caused by using two sensors in a three-dimensional measuring device.

[0014]

According to one aspect of the present invention, a three-dimensional measuring apparatus includes: a light projecting means for projecting a reference beam toward a measuring object; An image for calculating the three-dimensional shape of the object to be measured, and an image and a measuring object for calculating the three-dimensional shape of the object to be measured from the received reflected light. And an image for displaying is captured by the same sensor.

According to the present invention, an image for calculating the three-dimensional shape of the object to be measured and an image for displaying the object to be measured are captured by the same sensor. It is not necessary to adjust the mounting position of. In addition, it is not necessary to manufacture a prism capable of separating near-infrared light and visible light, and the image quality of a color image can be improved.

[0016]

FIG. 1 is a diagram showing a configuration of a measuring system 1 according to a first embodiment of the present invention. Referring to the drawings, a measurement system 1 includes a three-dimensional camera (range finder) 2 that performs three-dimensional measurement by a slit light projection method.
And a host 3 for processing output data of the three-dimensional camera 2.

The three-dimensional camera 2 displays color information of the object Q together with measurement data (slit image data) for specifying the three-dimensional positions of a plurality of sampling points on the object Q.
Outputs a three-dimensional image and data necessary for calibration. The host 3 is in charge of calculating the coordinates of the sampling points using the triangulation method.

The host 3 includes a CPU 3a, a display 3
b, a keyboard 3c, a mouse 3d, and the like. Software for processing measurement data is incorporated in the CPU 3a. Between the host 3 and the three-dimensional camera 2, both online and offline data transfer by the portable recording medium 4 is possible. As the recording medium 4, a magneto-optical disk (MO), a mini disk (MD),
There are memory cards and the like.

FIG. 2 is a view showing the appearance of the three-dimensional camera 2. A light projecting window 20a and a light receiving window 20b are provided on the front surface of the housing 20. The light emitting window 20a is a light receiving window 20.
b. Slit light emitted from the internal optical unit OU (band-like laser beam with a predetermined width w)
U travels toward the measurement target object (subject or measurement target) through the light projecting window 20a. Length direction M of slit light U
The radiation angle φ of 1 is fixed. A part of the slit light U reflected on the surface of the object enters the optical unit OU through the light receiving window 20b. Note that the optical unit OU includes a two-axis adjustment mechanism for optimizing the relative relationship between the light projecting axis and the light receiving axis.

On the upper surface of the housing 20, zooming buttons 25a and 25b, a manual focusing button 26
a, 26b and a shutter button 27 are provided. As shown in FIG. 2B, a liquid crystal display 21, a cursor button 22, a select button 23, a cancel button 24, an analog output terminal 3
2, a digital output terminal 33, and a detachable opening 30a for the recording medium 4 are provided.

The liquid crystal display 21 (LCD) is used as a scanning screen display means and an electronic finder. The photographer can set the photographing mode by using the buttons 22 to 24 on the back. Digital output terminal 3
3 outputs the measurement data, and the analog output terminal 32
Outputs a two-dimensional image signal in, for example, the NTSC format. The digital output terminal 33 is, for example, a SCSI terminal.

FIG. 3 is a block diagram showing a functional configuration of the three-dimensional camera 2. In the figure, solid arrows indicate the flow of electric signals, and broken arrows indicate the flow of light.

The three-dimensional camera uses the optical unit OU described above.
The two optical systems 40 and 5 on the light emitting side and the light receiving side that constitute
It has 0. In the optical system 40, a laser beam having a wavelength of 670 nm emitted from the semiconductor laser (LD) 41 passes through the light projecting lens system 42, becomes slit light U, and is deflected by the galvanomirror (scanning means) 43. The driver 44 of the semiconductor laser 41, the drive system 45 of the light projecting lens system 42, and the drive system 46 of the galvanomirror 43 are controlled by a system controller 61.

In the optical system 50, a zoom unit 51
The light condensed by the light enters the filter 80A.
Details of the filter 80A will be described later. Filter 8
The incident light through 0A is a color measurement sensor (CCD) 5
3a. The zoom unit 51 is of an in-focus type, and a part of the incident light is used for auto focusing (AF). The AF function is realized by an AF sensor 57, a lens controller 58, and a focusing drive system 59. The zooming drive system 60 is provided for electric zooming.

The image information obtained by the color measuring sensor 53a is synchronized with a clock from the driver 55 and stored in the memory 63.
Alternatively, it is transferred to the color processing circuit 67. The imaging information subjected to the color processing in the color processing circuit 67 is NTS
The image data is output online via the C conversion circuit 70 and the analog output terminal 32, or is quantized by the digital image generation unit 68 and stored in the color image memory 69. afterwards,
The color image data is transferred from the color image memory 69 to the SCSI.
The data is transferred to the controller 66, output online from the digital output terminal 33, or stored in the recording medium 4 in association with the measurement data. Note that the color image is an image having the same angle of view as the distance image obtained by the color measurement sensor 53a, and is used as reference information during application processing on the host 3 side. Examples of the process using color information include a process of generating a three-dimensional shape model by combining a plurality of sets of measurement data having different camera focal points.
There is a process of thinning out unnecessary vertices of the three-dimensional shape model. The system controller 61 gives a character generator (not shown) an instruction to display appropriate characters and symbols on the screen of the LCD 21.

The output processing circuit 62 has an amplifier for amplifying the photoelectric conversion signal of each pixel g output from the color measuring sensor 53a, and an A / D converter for converting the photoelectric conversion signal into 8-bit light receiving data. ing. The memory 63 has 20
This is a readable / writable memory having a storage capacity of 0 × 32 × 33 bytes, and stores light receiving data output from the output processing circuit 62. The memory control circuit 63A includes the memory 6
3 is specified.

The center-of-gravity calculating circuit 73 generates a grayscale image corresponding to the shape of the object to be measured based on the received light data stored in the memory 63, and outputs the grayscale image to the display memory 74.
Further, it calculates data serving as a basis for calculating the three-dimensional position, and outputs the calculated data to the output memory 64. On the screen of the LCD 21, a grayscale image stored in the display memory 74, a color image stored in the color image memory 69, and the like are displayed.

Note that the NTSC conversion circuit 70 outputs the video D /
A (analog image generation circuit). Filter 8
0A is switched by the filter switching mechanism 81A.

FIG. 4 is a diagram showing details of the periphery of the filter 80A and the filter switching mechanism 81A of FIG.

Referring to the figure, filter 80A has an IR
An (infrared) cut filter 80a and a band pass filter 80b are included. The filter switching mechanism 81A
The light incident via the light receiving lens 51a included in the zoom unit 51 is incident on the color measurement sensor 53a via the IR cut filter 80a, or the color measurement sensor 53a via the band pass filter 80b.
Is switched to be incident on the. That is, when capturing the distance image, the bandpass filter 80b corresponding to the wavelength of the reference light is used.
The IR cut filter 80a is used when a color image for display is captured. Color measurement sensor 53
a is driven by the driver 55. As described above, the distance image is processed by the output processing circuit 62 and then loaded into the memory 63. The color image data is output to the color processing circuit 67.

As described above, in the measurement system according to the present embodiment, both the distance image and the color image are captured by the same color measurement sensor 53a by shifting the timing. When the measurement object is in a stationary state or moves extremely slowly, this timing shift does not cause any particular problem in measurement.

Note that, depending on the light receiving lens 51a used and the wavelength of the reference light, a shift may occur between the focus position of the visible light and the focus position of the reference light. In this case, by changing the thickness of the filters 80a and 80b used, adjustment can be made so that the focal positions coincide.

As the color measuring sensor 53a (CCD), a sensor having a light receiving sensitivity characteristic in the wavelength band of the reference light in at least one channel is used. When some of the channels of the color measurement sensor 53a have light receiving sensitivity characteristics in the wavelength band of the reference light, only the specific channel having light receiving sensitivity characteristics is used for capturing a distance image. For example, only the R (red) channel is used for distance image capture. When all the channels of the color measurement sensor 53a have the light receiving sensitivity characteristics in the wavelength band of the reference light (when the measurement sensitivity is not affected), all the channels (R, G (green), B (Blue)) is used for range image capture.

The filter 80A may be placed anywhere before the color measuring sensor 53a. However, the light receiving lens 51a and the color measuring sensor 53
It is desirable to install between them. This is because the area of the filters 80a and 80b can be reduced, and the load on the filter switching mechanism 81A can be reduced.

In this embodiment, (R, G,
Although the example using the color CCD having the configuration B) has been described, the color CCD having the configuration (G, Cy, Ye, Mg) may be used as the color measurement sensor 53a.

By employing the configuration of the present embodiment, the distance image and the color image are read by the same sensor, so that it is not necessary to adjust the mounting positions of the two sensors as in the related art. In addition, it is not necessary to manufacture a prism capable of separating the near-infrared light and the visible light, and the quality of a color image can be improved.

Further, since only one sensor is required, the number of peripheral circuits can be reduced as compared with the related art.

FIG. 5 is a block diagram showing a configuration of a three-dimensional camera according to the second embodiment of the present invention. The differences between the three-dimensional camera in the second embodiment and the first embodiment will be described below. In the second embodiment, a filter 80B is used instead of the filter 80A (see FIG. 3) in the first embodiment.
Further, a filter switching mechanism 81B is used instead of the filter switching mechanism 81A (see FIG. 3). Further, a monochrome measurement sensor (monochrome CCD) 53b is used instead of the color measurement sensor 53a (see FIG. 3). In the second embodiment, a monochrome measurement sensor 53b
Is directly input to the digital image generation unit 68. That is, in the second embodiment, the color processing circuit 67
Is not provided.

FIG. 6 shows a filter 80 according to this embodiment.
FIG. 5B is a diagram illustrating a configuration around B and a monochrome measurement sensor 53b.

The filter 80B includes a B filter 80c, a G filter 80d, an R filter 80e, and a band pass filter 80f. The B filter 80c, the G filter 80d, and the R filter 80e are filters for a color image. The filter switching mechanism 81B controls the respective filters so that the reflected light incident through the light receiving lens 51a is incident on the monochrome measuring sensor 53b after passing through any of the filters. The monochrome measurement sensor 53b is driven by the driver 55, and the output of the monochrome measurement sensor 53b is input to the memory 63 or the digital image generation unit 68 via the output processing circuit 62.

In this embodiment, the filters are switched by the filter switching mechanism 81B, and a bandpass filter 80 corresponding to the wavelength of the reference light is used at the time of capturing a range image.
Use f. On the other hand, when a color image is captured, R, G, B
Using the filters 80c to 80e sequentially, three image captures corresponding to the color images are performed.

In this embodiment, since the monochrome measuring sensor 53b can be used, the number of driving circuits and processing circuits around the sensor 53b can be reduced as compared with the first embodiment, and the cost of the apparatus can be reduced. be able to.

In the above embodiment, R,
G and B color separation filters are used,
An M, Y color separation filter may be used. Further, if a color image is reproduced, a configuration of another color may be adopted.

FIG. 7 is a block diagram showing a configuration of a three-dimensional camera according to the third embodiment of the present invention. The differences between the three-dimensional camera of the present embodiment and the first embodiment will be described below. No color image is displayed on the three-dimensional camera in the present embodiment. Only the monochrome luminance image is displayed on the LCD 21. Instead of the filter 80A and the color measurement sensor 53a in FIG.
A sensor 53c for 0C and monochrome measurement (or a sensor for color measurement) may be employed. FIG.
Filter switching mechanism 81A and color processing circuit 6
7, a digital image generator 68 and a color image memory 69
The NTSC converter 70 and the analog output terminal 32 are not employed in the present embodiment.

FIG. 8 is a diagram for explaining the configuration around the filter 80C and the monochrome measuring sensor 53c of FIG.

The filter 80C is a bandpass filter 80.
Contains only g. The reflected light from the measurement object input via the light receiving lens 51a is input to the monochrome measurement sensor 53c via the band pass filter 80g. The monochrome measurement sensor 53c is driven by the driver 55. The output of the monochrome measurement sensor 53c is input to the memory 63 via the output processing circuit 62.

In the present embodiment, image data picked up by the monochrome measuring sensor 53c is used as a distance image and a display image. That is, also in the present embodiment, the distance image and the display image are input by one sensor.

As a monochrome luminance image used for display, $ xi, which is data used for calculating the center of gravity, is used. First, the method of obtaining Σxi and the reason why it can be used as a monochrome luminance image for display will be described.

FIG. 9 is a schematic diagram showing the structure of the light projecting lens system 42. FIG. 9A is a front view, and FIG. 9B is a side view.

The light projecting lens system 42 includes the collimator lens 4
21, a variator lens 422, and an expander lens 423. The laser beam emitted by the semiconductor laser 41 is subjected to an optical process for obtaining an appropriate slit light U in the following order. First, the beam is collimated by the collimator lens 421. Next, the beam diameter of the laser beam is adjusted by the variator lens 422. Finally, the beam is expanded by the expander lens 423 in the slit length direction M1.
Spread out.

The variator lens 422 is provided to allow the slit light U having a width of three or more pixels to enter the measuring sensor 53c regardless of the photographing distance and the angle of view of photographing. The drive system 45 operates according to an instruction from the system controller 61 so that the width w of the slit light U on the measurement sensor 53c is kept constant.
Move 2 The variator lens 422 and the zoom unit 51 on the light receiving side are linked.

By increasing the slit length before the polarization by the galvanomirror 43, the distortion of the slit light U can be reduced as compared with the case where the polarization is performed after the polarization. By arranging the expander lens 423 at the last stage of the light projecting lens system 42, that is, by bringing it closer to the galvanometer mirror 43, the size of the galvanometer mirror 43 can be reduced.

FIG. 10 is a principle diagram of calculation of a three-dimensional position in the measurement system 1. In the figure, only five samplings of the amount of received light are shown for easy understanding.

The object Q is irradiated with a relatively wide slit light U of a plurality of pixels on the imaging surface S2 of the measurement sensor 53c. Specifically, the width of the slit light U is set to 5 pixels. The slit light U is applied to the imaging surface S every sampling cycle.
Polarized from top to bottom in FIG. 10 so as to move by one pixel pitch pv on 2, thereby scanning the object Q. One frame of light reception data (photoelectric conversion information) is output from the monochrome measurement sensor 53c for each sampling cycle. This polarization is actually performed at a constant angular velocity.

Focusing on one pixel g on the imaging surface S2,
In the present embodiment, 32 light reception data are obtained by 32 samplings performed during scanning. By calculating the center of gravity of these 32 received light data,
The object surface ag in the range where the pixel of interest g glare is slit light U
(Time centroid Npeak or centroid ip) is determined.

If the surface of the object Q is flat and there is no noise due to the characteristics of the optical system, the amount of light received by the target pixel g is
As shown in FIG. 10B, the number increases at the timing when the slit light U passes, and usually approaches a normal distribution. When the amount of received light is maximum between the n-th time and the immediately preceding (n-1) -th time as shown in the figure, the timing substantially coincides with the time barycenter Npeak.

The position (coordinates) of the object Q is calculated based on the relationship between the irradiation direction of the slit light at the calculated time barycenter Npeak and the incident direction of the slit light on the target pixel. This enables measurement with a higher resolution than the resolution defined by the pixel pitch pv of the imaging surface.

The amount of light received by the target pixel g depends on the reflectance of the object Q. However, the relative ratio of each received light amount of sampling is constant regardless of the absolute amount of received light. That is, the shading of the object color does not affect the measurement accuracy.

FIG. 11 is a diagram showing a reading range of the monochrome measuring sensor 53c. As shown in FIG. 11, the reading of one frame by the monochrome measurement sensor 53c is not performed on the entire imaging surface S2 but on the imaging surface S2 in order to increase the speed.
Is performed only for the effective light receiving area (band-shaped image) Ae which is a part of. The effective light receiving area Ae is an area on the imaging surface S2 corresponding to the measurable distance range d 'of the object Q at a certain irradiation timing of the slit light U, and one pixel for each frame according to the polarization of the slit light U. shift. In the present embodiment, the number of pixels in the shift direction of the effective light receiving area Ae is fixed to 32. A method of reading out only a part of a captured image of a CCD area sensor is disclosed in
No. 536.

FIG. 12 is a diagram showing the relationship between lines and frames on the imaging surface S2 of the monochrome measuring sensor 53c. FIGS. 13 to 15 are diagrams showing the storage state of the light receiving data of each frame in the memory 63.

As shown in FIG. 12, frame 1 which is the first frame of the image pickup surface S2 includes lines 1 to 3
Light reception data for 32 (lines) × 200 pixels up to 2 is included. Frame 2 is from line 2 to line 33
Frame 3 is shifted by one line per frame, such as from line 3 to line 34. Frame 32 is from line 32 to line 63. As described above, one line has 200 pixels.

The received light data from frame 1 to frame 32 are sequentially transferred to memory 63 via output processing circuit 62 and stored in memory 63 in the state shown in FIG.

That is, the memory 63 stores the frame 1,
The light receiving data is stored in the order of 2, 3,. The data of the line 32 included in each frame is shifted upward by one line for each frame, such as the 32nd line for the frame 1 and the 31st line for the frame 2. When the light reception data from frame 1 to frame 32 is stored in the memory 63, the time barycenter Npeak is calculated for each pixel on the line 32.

While the calculation for the line 32 is being performed, the received light data of the frame 33 is transferred to the memory 63 and stored. As shown in FIG.
Is stored in the area next to the frame 32 of the memory 63. When the data of the frame 33 is stored in the memory 63, the time barycenter Npe is calculated for each pixel of the line 33 included in the frames 2 to 33.
ak is calculated.

While the calculation for the line 33 is being performed, the received light data of the frame 34 is transferred to the memory 63 and stored. As shown in FIG.
Is overwritten in the area stored in the frame 1. At this point, since the data of frame 1 has been processed, it can be erased by overwriting. When the data of the frame 34 is stored in the memory 63, for each pixel of the line 34, the time centroid Npeak
Is calculated. When the processing of the light reception data of the frame 34 is completed, the light reception data of the frame 35 is overwritten on the area stored in the frame 2.

In this way, the time barycenter Npeak is calculated for a total of 200 lines up to the last line 231.

As described above, of the light reception data stored in the memory 63, new light reception data is sequentially overwritten and stored in the area where unnecessary data is stored, so that the capacity of the memory 63 is reduced. You.

Next, the configuration of the center-of-gravity calculating circuit 73 and the calculation processing of the time center-of-gravity Npeak by the center-of-gravity calculating circuit 73 will be described.

FIG. 16 is a block diagram showing the structure of the center-of-gravity calculating circuit 73, FIG. 17 is a diagram showing the concept of data transfer timing, and FIG. 18 is a diagram showing the concept of the time center of gravity Npeak.

As shown in FIG. 18, the time center of gravity Npe
ak is the center of gravity of 32 pieces of received light data obtained by 32 samplings. Sampling numbers 1 to 32 are assigned to 32 pieces of received light data for each pixel. The i-th received light data is represented by xi. i is 1
Is an integer of up to 32. At this time, i indicates the number of frames for one pixel after the pixel enters the effective light receiving area Ae.

The center of gravity ip for the 1st to 32nd received light data x1 to x32 is calculated by calculating the value of i ·
It is obtained by dividing the sum Σi · xi of xi by the sum Σxi of xi. That is,

[0072]

(Equation 1)

Is obtained.

The center-of-gravity calculating circuit 73 calculates the center of gravity ip (that is, the time center of gravity Npeak) for each pixel based on the data read from the memory 63. However, instead of using the data read from the memory 63 as it is, a value obtained by subtracting the steady light data ks from each data (0 when the value is negative) is used. That is, the offset is given to the received light data output from the measurement sensor 53c by subtracting the amount of the stationary light data ks.

The stationary light data ks is data calculated based on the light receiving data of the pixel when the slit light U is not incident. The stationary light data ks may use a predetermined fixed value, or the monochrome measurement sensor 53c
May be obtained in real time using the data output from. In the case of a fixed value, the monochrome measurement sensor 53 is used.
When the output of c is 8 bits (256 gradations), for example, “5”, “6” or “10” is set. In the case of real-time calculation, 32
The average value of the received light data for each of the two pixels before and after the received light data is obtained, and the smaller of the average values is determined as the constant light data k.
s. The reason is that the slit light U does not enter before or after the effective light receiving area Ae, so that the light receiving data when the slit light U does not enter can be reliably obtained in real time. is there. Alternatively, the larger one of the average values of the received light data for each of the two pixels before and after may be used as the stationary light data ks. The average value of the light reception data of the two pixels before the 32 light reception data or the average value of the light reception data of the two pixels after the 32 light reception data may be used. Light reception data for one pixel may be used. Further, depending on the shape of the object Q or the state of noise included in the received light data, a value obtained by adding a predetermined value (for example, “5”) to these values is used as the constant light data ks
, The offset may be increased, and unnecessary noise components may be more reliably cut.
In these cases, the size of one frame is 36 lines, 34 lines, or 33 lines, and the data of the center of gravity ip may be calculated using 32 data of 32 lines.

Now, referring to FIG.
Comprises a stationary light data storage unit 731, a subtraction unit 732, a first addition unit 733, a second addition unit 734, and a division unit 735. These are realized by using software, but it is also possible to configure all or some of them by a hardware circuit.

The stationary light data storage section 731 stores the stationary light data ks. The subtraction unit 732 subtracts the steady term data ks from the input light receiving data. Here, the data output from the subtraction unit 732 is referred to as light reception data xi again. The first adding unit 733 adds i · xi for i = 1 to 32 and outputs the total value. Second adder 73
4 adds xi for i = 1 to 32 and outputs the total value. The divider 735 divides the output value of the first adder 733 by the output value of the second adder 734, and outputs the center of gravity ip. The barycenter ip output from the divider 735 is stored in the display memory 74. The output value of the first adder 733 and the output value of the second adder 734 are stored in the output memories 64a and 64b, respectively. Output memory 6
The data stored in 4a and 64b is output from the digital output terminal 33 to the host 3 via the SCSI controller 66, or stored in the recording medium 4. In the host 3, a three-dimensional position calculation process is performed based on these data, and the reliability of these data is determined.

Referring to FIG. 17, memory control circuit 63A
Specifies the address of the memory 63 sequentially for each pixel so that the above-described processing by the centroid operation circuit 73 is performed for one pixel. For example, for the first line 32, line 3 included in frame 1 shown in FIG.
Data of the first pixel of line 2, line 3 included in frame 2
For the first pixel data of the line 32, a total of 3
Two data are sequentially addressed. By addressing, data is read from the memory 63 and sent to the center-of-gravity calculating circuit 73. While the calculation for the line 32 is being performed, the received light data of the next frame 33 is transferred to the memory 63. Thereafter, reading from and writing to memory 63 are performed in parallel, whereby the circuit operates efficiently.

In the center-of-gravity calculating circuit 73, the division unit 735 outputs the center of gravity ip when 32 data are input. Subsequently, processing is sequentially performed up to the data of the 200th pixel, such as the data of the second pixel and the data of the third pixel, and the calculation of the barycenter ip for the line 32 is completed.
After the calculation of the center of gravity ip for the line 32 is completed, the calculation of the center of gravity ip is performed for all 200 lines up to the line 231 such as the line 33, the line 34, and the line 35.

The monochrome measuring sensor 53c, which is a CCD area sensor, has an integration area and an accumulation area, and when the integration operation in the integration area is completed, charges are transferred to the accumulation area at once, and sequentially from the accumulation area to the outside. Output.

The center of gravity ip stored in the display memory 74
Is displayed on the screen of the LCD 21. The center of gravity ip is related to the position of the surface of the object Q to be measured. When the position of the surface of the object Q is close to the three-dimensional camera 2, the value of the center of gravity ip increases, and when the position of the surface of the object Q is far, the value of the center of gravity ip decreases. . Therefore, the distance distribution can be expressed by displaying a grayscale image using the center of gravity ip as the density data.

Note that the configuration shown in FIGS.
This is also adopted in the second embodiment.

In this embodiment, a monochrome luminance image can be displayed on the display 3b by using $ xi.
Can be displayed. That is, Σxi is the total output of 32 frames. In any one of the 32 frames, the reflected light of the slit light from the subject is received (here, it is assumed that the subject is within the measurable range). Bandpass filter 8
Since the ambient light is almost cut by 0g,
Is the sum of the components of the slit light irradiated during the period of 32 frames. Similarly, the sum of the slit light components is obtained for all the pixels. When Σxi of each pixel is treated as display luminance data of each pixel, a monochrome image (monochrome image with respect to the slit light wavelength) is obtained.

For example, if the data range of $ xi is 1
If 3 bits are prepared and 8-bit data is used for monochrome luminance display, 8 bits obtained by removing the upper 3 bits and the lower 2 bits of $ xi may be used. Which 8-bit data is used depends on
What is necessary is just to determine in consideration of the value which Σxi actually takes.

In the present embodiment, a case where a CCD is used as an image sensor has been described. However, a distance image and a color image can be captured even when a CMOS image sensor or the like is used as an image sensor.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration of a measurement system according to a first embodiment of the present invention.

FIG. 2 is a diagram showing an appearance of a three-dimensional camera 2.

FIG. 3 is a block diagram showing a functional configuration of the three-dimensional camera 2.

FIG. 4 is a diagram showing a configuration around a filter 80A and a filter switching mechanism 81A.

FIG. 5 is a block diagram of a three-dimensional camera according to a second embodiment of the present invention.

FIG. 6 is a diagram showing a configuration around a filter 80B and a filter switching mechanism 81B.

FIG. 7 is a block diagram illustrating a configuration of a three-dimensional camera according to a third embodiment of the present invention.

FIG. 8 is a diagram showing a configuration around a filter 80C.

FIG. 9 is a schematic diagram showing a configuration of a light projecting lens system.

FIG. 10 is a principle diagram of calculation of a three-dimensional position in the measurement system.

FIG. 11 is a diagram showing a reading range of a sensor.

FIG. 12 is a diagram illustrating a relationship between a line and a frame on an imaging surface of a sensor.

FIG. 13 is a diagram illustrating a storage state of light reception data of each frame in a memory.

FIG. 14 is a diagram illustrating a storage state of light reception data of each frame in a memory.

FIG. 15 is a diagram showing a storage state of light reception data of each frame in a memory.

FIG. 16 is a block diagram illustrating a configuration of a centroid operation circuit.

FIG. 17 is a diagram illustrating the concept of data transfer timing.

FIG. 18 is a diagram illustrating a concept of a time center of gravity.

FIG. 19 is a view for explaining a configuration of a conventional active type three-dimensional measuring apparatus.

[Explanation of symbols]

 53a-53c Measurement Sensor (CCD) 80A-80C Filter 81A-81C Filter Switching Mechanism

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hideki Tanabe 2-3-13 Azuchicho, Chuo-ku, Osaka City Osaka International Building Minolta Co., Ltd. (72) Inventor Eiichi Ide 2-chome Azuchicho, Chuo-ku, Osaka City No. 3-13 Osaka International Building Minolta Co., Ltd. (72) Inventor Koichi Sukebe 2-3-1 Azuchicho, Chuo-ku, Osaka City Osaka International Building Minolta Co., Ltd.

Claims (1)

[Claims] A light projecting unit for projecting a reference light toward the object to be measured; a light receiving unit for receiving light reflected from the object to be measured; A three-dimensional measuring apparatus comprising: a calculating unit that calculates a three-dimensional shape, wherein an image for calculating a three-dimensional shape of the measurement target and an image for displaying the measurement target are the same sensor. A three-dimensional measuring device characterized in that it is taken in by a.