JPH11271030A - Three-dimensional measuring apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To deal with a measurement for various purposes under various measuring conditions by using one three-dimensional measuring apparatus by a method wherein a means which selects an operating mode is installed and a means by which the operating speed of reference light and the readout operation of a light receiving sensor are changed over according to the selected operating mode is installed. SOLUTION: As an operating mode, a standard mode, a high-speed mode, a wide-Z mode, a high-sensitivity mode, a high-resolution mode, a high-speed and high-wide-Z mode or the like is available according to a performance factor to which priority is given. Then, when the operating mode is set by a measurement start operation, a parameter which corresponds to the operating mode is read out. As the parameter, a readout width parameter, a line interval GT parameter, a shift number GS parameter, a high-sensitivity parameter or the like is available, and the parameter is output to a driver 55. In addition, according to the operating mode, the width and the scanning speed of slit light are set. When the wide-Z mode or the high-speed and high-wide-Z mode is set, a diaphragm is narrowed down. The processing operations are performed by a system controller 61.

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 apparatus for irradiating an object with reference light such as slit light or spot light to measure the shape of the object in a non-contact manner.

[0002]

2. Description of the Related Art Conventionally, a three-dimensional measuring apparatus to which a slit light projection method (also referred to as a light cutting method) is applied is known (Japanese Patent Laid-Open No. 9-196632). The slit light projection method
This is a method of obtaining a three-dimensional image (distance image) by optically scanning an object, and is a kind of active measurement method of irradiating a specific reference light and photographing the object. In the slit light projection method, a slit light having a linear cross section is used as reference light.

In performing three-dimensional measurement, there are various cases for the purpose of the measurement (measurement). For example, there are various purposes depending on the purpose, such as when it is desired to take a picture at high speed in as short a time as possible, when the measurement speed may be slow but it is desired to measure with high resolution, or when it is desired to measure an object having a large depth.

[0004]

However, according to the conventional three-dimensional measuring device, measurement can be performed only for the purpose corresponding to the specification of the three-dimensional measuring device. For example, the measurement speed, depth in the depth direction that can be measured, and resolution are specified as specified values as specifications, and if you want to measure at higher speed, you want to measure at higher resolution. Couldn't cope when we wanted to make a big change.

Therefore, conventionally, it has been necessary to purchase and prepare the three-dimensional measuring apparatus itself in accordance with the purpose of measurement. The present invention has been made in view of the above-described problems, and has as its object to provide a three-dimensional measurement device that can use one three-dimensional measurement device to measure various purposes under various measurement conditions.

[0006]

According to a first aspect of the present invention, there is provided an apparatus for irradiating a measuring object with a reference beam, scanning the reference beam, and receiving reflected light of the measuring object. And a means for repeatedly driving the light receiving sensor during the scanning of the reference light to read out an output signal, and measuring a three-dimensional shape of a measurement target based on the output signal of the light receiving sensor. The dimension measurement device includes means for selecting an operation mode, and means for switching a scanning speed of the reference light and a reading operation of the light receiving sensor according to the selected operation mode.

According to a second aspect of the present invention, there is provided an apparatus comprising means for selecting an operation mode, and means for switching a line width in reading out the light receiving sensor according to the selected operation mode.

According to a third aspect of the present invention, there is provided an apparatus comprising: means for selecting an operation mode; and means for switching a line interval in reading out the light receiving sensor according to the selected operation mode.

According to a fourth aspect of the present invention, there is provided an apparatus for selecting an operation mode, for switching the scanning speed of the reference light in accordance with the selected operation mode, and for selecting the operation mode in accordance with the selected operation mode. Means for switching a line width in reading out the light receiving sensor, and means for switching a line interval in reading out the light receiving sensor according to a selected operation mode.

According to a fifth aspect of the present invention, there is provided an apparatus for selecting an operation mode, and for switching a line width of an effective light receiving area of the light receiving sensor and a line interval in reading in accordance with the selected operation mode, Means for switching the number of line shifts for each frame in reading by the light-receiving sensor in accordance with the selected operation mode.

According to a sixth aspect of the present invention, there is provided an apparatus having means for switching between skipping a line in the middle or adding a read output signal when the number of shifts is plural.

As shown in FIG. 12, the measurement speed QS and the measurement range Q, which is a dynamic range in the depth direction (Z direction), are factors that indicate the performance of the three-dimensional measurement device.
There are R, resolution QD, sensitivity QB, and a measurement area QB which is a dynamic range in the vertical direction (Y direction).

These performances are determined by the number of lines (the number of readout lines) of the effective light receiving area Ae of the light receiving sensor.
GL, the entire line width (readout line width) GW of the effective light receiving area Ae, the line interval GT which is a value obtained by dividing the line width GW by the number of lines GL, the number of shifts GS, and the slit light width GP (the width of the slit light U) w).

Normally, for example, when the number of lines GL decreases, the reading is performed at a high speed.
Is faster. As the line width GW increases, the dynamic range in the depth direction (Z direction) increases, so that the measurement range QR increases. As the shift number GS decreases, the resolution QD increases.

The operation mode includes a standard mode, a high-speed mode, and a high-speed mode depending on which of the performance factors is prioritized.
There are a wide Z mode, a high sensitivity mode, a high resolution mode, and a high speed and wide Z mode. There are various variations in each operation mode. By setting these operation modes in various ways, it is possible to cope with various purposes of measurement.

[0016]

FIG. 1 is a configuration diagram of a measurement system 1 according to the present invention. The 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 that processes 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 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,
There are a magneto-optical disk (MO), a mini disk (MD), and a memory card.

FIG. 2 is a view showing the appearance of the three-dimensional camera 2. A light emitting window 20a and a light receiving window 2 are provided on the front of the housing 20.
0b is provided. The light projecting window 20a is located above the light receiving window 20b. Slit light (band-like laser beam with a predetermined width w) U emitted from the internal optical unit OU
Goes to the object (subject) to be measured through the light emitting window 20a. The radiation angle φ in the length direction M1 of the slit light U 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, on the back of the housing 20,
A liquid crystal display 21, a cursor button 22, a select button 23, a cancel button 24, analog output terminals 31 and 32, 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 display means for an operation screen and as an electronic finder.
The photographer can set the photographing mode by using the buttons 21 to 24 on the back. In particular, select button 23
The operation mode is set. The analog output terminal 31 outputs measurement data, and the analog output terminal 31 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. 3D camera 2
Has two optical systems 40 and 50 on the light projecting side and the light receiving side that constitute the optical unit OU described above. Optical system 40
, The wavelength 6 emitted by the semiconductor laser (LD) 41
The 85 nm laser beam becomes slit light U by passing through the light projecting lens system 42 and is deflected by a galvanomirror (scanning means) 43. Semiconductor laser 4
The driver 44, the driving system 45 of the light projecting lens system 42, and the driving 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 beam splitter 52 is split by the beam splitter 52. The light in the oscillation wavelength band of the semiconductor laser 41 is
The light enters the sensor 53 for measurement. Light in the visible band enters the monitor color sensor 54. The sensor 53 and the color sensor 54 are both CCD area sensors. 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 aperture driving system 59a is provided for controlling the aperture of the aperture.

The information captured by the sensor 53 is transmitted to the driver 5.
5 and is transferred to the output processing circuit 62 in synchronization with the clock from the fifth clock. Measurement data corresponding to each pixel of the sensor 53 is generated by the output processing circuit 62 and stored in the memories 63 and 64. Thereafter, when the operator instructs data output, the measurement data is transmitted to the SCSI controller 66 or N
The data is output online in a predetermined format by the TSC conversion circuit 65 or stored in the recording medium 4. An analog output terminal 31 or a digital output terminal 33 is used for online output of measurement data. Image information from the color sensor 54 is transferred to the color processing circuit 67 in synchronization with a clock from the driver 56. The color-processed imaging information is output online via the NTSC conversion circuit 70 and the analog output terminal 32, or quantized by the digital image generation unit 68 and stored in the color image memory 69. Thereafter, the color image data is transferred from the color image memory 69 to the SCSI controller 66, output online from the digital output terminal 33, or stored in the recording medium 4 in association with the measurement data. In addition,
The color image is an image having the same angle of view as the distance image obtained by the sensor 53, and is used as reference information during application processing on the host 3 side. The processing using color information includes, for example, processing of generating a three-dimensional shape model by combining a plurality of sets of measurement data having different camera viewpoints, and processing of thinning out unnecessary vertices of the three-dimensional shape model. The system controller 61 gives an instruction to the character generator 71 to display appropriate characters and symbols on the screen of the LCD 21.

FIG. 4 is a schematic diagram showing the configuration of the light projecting lens system 42. FIG. 4A is a front view, and FIG. 4B is a side view. The projection lens system 42 includes the collimator lens 4
21, a variator lens 422, and an expander lens 423. The laser beam emitted from 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 (slit scanning direction) M1.

The variator lens 422 is provided to allow the slit light U having a width of three or more pixels to enter the sensor 53 irrespective of the photographing distance and the angle of view of photographing. The drive system 45 moves the variator lens 422 so as to keep the width w of the slit light U on the sensor 53 constant according to an instruction from the system controller 61. The variator lens 422 and the zoom unit 51 on the light receiving side are linked. Further, in accordance with an instruction from the system controller 61, the width w of the slit light U is controlled according to an operation mode described later.

By increasing the slit length before deflection by the galvanomirror 43, distortion of the slit light U can be reduced as compared with the case where deflection is performed after deflection. 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. 5 is a diagram illustrating the principle of calculating a three-dimensional position in the measurement system 1, FIG. 23 is a diagram illustrating an outline of the slit light projection method, and FIG. 24 is a diagram illustrating the principle of measurement by the slit light projection method. is there. 5 and FIG.
Elements corresponding to 4 are denoted by the same reference numerals.

The object Q is irradiated with a relatively wide slit light U corresponding to a plurality of pixels on the imaging surface S2 of the sensor 53. The width of the slit light U is set to 5 pixels in the standard mode, but is switched to a different pixel according to the operation mode. For example, when the line interval is “2” in the high-speed mode or the wide Z mode, the width w is set to 10 pixels. Further, the slit light U is deflected for scanning the object Q. The moving direction of the slit light U is shown in FIG.
Is a direction from the top to the bottom on the imaging surface S2 shown in FIG. In the standard mode, the moving speed of the slit light U is set so as to move by one pixel pitch pv on the imaging surface S2 every sampling period, but is switched to a different speed according to the operation mode. For example, when a later-described shift number GS is set to “2” in the high-speed mode or the wide Z mode, the image is moved by two pixel pitches (2 pv) every sampling period. One frame of photoelectric conversion information is output from the sensor 53 every sampling period.

Focusing on one pixel g on the imaging surface S2,
Effective light receiving data is obtained in five samplings out of N samplings performed during scanning. The timing at which the optical axis of the slit light U passes through the object surface ag in the range in which the target pixel g is glazed (the time barycenter Npeak: the time when the amount of received light of the target pixel g is maximum) is obtained by an interpolation operation on these five received light data. . In the example of FIG. 5B, the amount of received light is maximum between the n-th time and the (n-1) -th time immediately before the n-th time. The position (coordinate) of the object Q based on the relationship between the irradiation direction of the slit light at the obtained timing and the incident direction of the slit light on the target pixel
Is calculated. 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 the amount of received light in the five samplings is constant regardless of the absolute amount of received light. That is, the shading of the object color does not affect the measurement accuracy.

In the measurement system 1 of this embodiment, the three-dimensional camera 2 outputs the received light data of five times for each pixel g of the sensor 53 to the host 3 as measurement data, and the host 3 outputs the object Q based on the measurement data. Calculate the coordinates. The output processing circuit 62 (see FIG. 3) of the three-dimensional camera 2 is responsible for generating measurement data corresponding to each pixel g.

FIG. 6 is a block diagram of the output processing circuit 62, FIG. 7 is a diagram showing a reading range of the sensor 53, and FIG. 8 is a diagram showing an example of a configuration in the case of interline transfer of the CCD area sensor.

The output processing circuit 62 includes an AD converter 620 for converting the photoelectric conversion signal of each pixel g output from the sensor 53 into 8-bit light receiving data, and four frame delay memories 621a to 624a and 621 connected in series.
b to 624b, selectors 621c to 624c, valid 5
Five memory banks 625A to 625A for storing the received light data of the times, a memory bank 625F for storing a frame number (sampling number) FN in which the received light data is maximum, a comparator 626, a generator 627 for indicating the frame number FN, And the memory bank 625
It is composed of memory control means (not shown) for specifying addresses A to F. Each memory bank 625A-E
Has a capacity capable of storing the same number of received light data as the number of measurement sampling points (that is, the number of effective pixels of the sensor 53).

The AD conversion unit 620 outputs 32
The light receiving data D620 for the line is serially output in the arrangement order of the pixels g. Four frame delay memories 621
a to 624a and 621b to 624b are for delaying data, respectively, so that light receiving data for 5 frames for each pixel g can be stored in the memory banks 625A to 625A at the same time. . Four frame delay memories 621a to 624a
And 621b to 624b are respectively 31 (= 32−
1) A FIFO having a capacity for a line or 15 (= 16-1) lines. Selectors 621c to 624c
Corresponds to the frame delay memory 62 according to the operation mode.
One of the outputs 1a to 624a or 621b to 624b is selected.

The reading of one frame by the sensor 53 is performed not on the entire imaging surface S2 but on only a part of the effective light receiving area (band image) Ae of the imaging surface S2 as shown in FIG. Done. The number of pixels in the shift direction (vertical direction) of the effective light receiving area Ae (that is, the number of lines GL)
Is "32" in the standard mode, but is set to "16" or "64" depending on the operation mode. Further, the effective light receiving area Ae shifts by a predetermined pixel for each frame with the deflection (scanning) of the slit light U. The shift number GS for each frame is one pixel in the standard mode, but is two pixels depending on the operation mode.

As described above, the number of lines GL and the number of shifts GS of the effective light receiving area Ae are changed according to the mode. The control for the change is performed by the system controller 61 outputting an instruction signal to the driver 55 of the sensor 53 for measurement. The driver 55 drives the sensor 53 while controlling the number of lines GL and the number of shifts GS of the effective light receiving area Ae of the sensor 53 based on an instruction signal from the system controller 61.

A method of reading out only a part of the captured image of the CCD area sensor is disclosed in Japanese Patent Laid-Open Publication No. Hei 7-174536. In this embodiment, in order to read out only the effective light receiving area Ae from the sensor 53, In order to read only necessary lines in the effective light receiving area Ae,
The method is applied.

The outline of the method will be described with reference to FIG. 8. The accumulated electric charge is discharged to the overflow drain OD up to the start line of the effective light receiving area Ae of the sensor 53. In the effective light receiving area Ae, one shift signal is input to the transfer gate, each electric charge in the lowermost vertical register is read out to the horizontal register HRG, and thereafter, one image is output by the horizontal shift signal. The charge after the end line of the effective light receiving area Ae is overflow drain OD
Discharge to

Therefore, in the operation mode in which reading is performed every other line, control is performed so that the data is discharged to the overflow drain OD every other line when reading the effective light receiving area Ae. Shift number GS of effective light receiving area Ae
Is performed by shifting the setting of the start line of the effective light receiving area Ae. In the mode for adding two lines, for example, in the high sensitivity mode, the transfer gate TG
After inputting two shift signals to the horizontal register HRG
Read from

When reading from the sensor 53, if the number of lines GL in the effective light receiving area Ae is "32", the 31-line delay output from the frame delay memories 621a to 624a is output, and if the number of lines GL is "16". To the frame delay memories 621b to 624b.
5 line delay output is selected respectively. When a mode in which the number of lines GL of the effective light receiving area Ae is set to "64" is provided, a frame delay memory for 63-line delay is further provided, and its output can be selected.

When the received light data D620 of the target pixel g output from the AD converter 620 is delayed by two frames, the comparator 626 outputs the past received light data D620 of the target pixel g stored in the memory bank 625C by the comparator 626. Is compared to the maximum value of The delayed light reception data D620 (frame delay memory 622a or 622b)
Is larger than the past maximum value, the output of the AD conversion unit 620 and the output of each frame delay memory 621a to 624a or 621b to 624b at that time are:
The data is stored in the memory banks 625A to 625E, respectively, and the stored contents of the memory banks 625A to 625E are rewritten. At the same time, the memory bank 625F contains the memory bank 625F.
The frame number FN corresponding to the light receiving data D620 stored in C is stored.

That is, when the amount of light received by the target pixel g becomes the maximum in the n-th (n <N) frame, the data of the (n + 2) th frame is stored in the memory bank 625A, and is stored in the memory bank 625B. The data of the (n + 1) th frame is stored, and the data of the nth frame is stored in the memory bank 625C.
Data of the (n-1) th frame is stored in D, data of the (n-2) th frame is stored in the memory bank 625E, and n is stored in the memory bank 625F.

Next, the operation of the three-dimensional camera 2 and the host 3 will be described together with the measurement procedure. Hereinafter, the number of measurement sampling points is assumed to be 200 × 231. That is, the number of pixels in the slit length direction on the imaging surface S2 is 231 and the substantial number of frames N is 200.

The user (photographer) determines the camera position and orientation while viewing the color monitor image displayed on the LCD 21, and sets the angle of view. At that time, a zooming operation is performed as needed. In the three-dimensional camera 2, the aperture adjustment of the color sensor 54 is not performed, and a color monitor image whose exposure is controlled by the electronic shutter function is displayed. This is because the incident light amount of the sensor 53 is increased as much as possible by opening the aperture.

FIG. 9 is a diagram showing a data flow in the three-dimensional camera 2, FIG. 10 is a diagram showing a data flow in the host 3, and FIG. 11 is a diagram showing a relationship between each point of the optical system and the object Q. .

The variator unit 51 of the zoom unit 51 is operated in accordance with the angle of view selection operation (zooming) by the user.
4 is performed. Also, manual or automatic focusing by moving the focusing unit 512 is performed.
In the course of focusing, the approximate inter-object distance d ₀ is measured.

In response to such lens driving of the light receiving system, the amount of movement of the variator lens 422 on the light projecting side is calculated by an arithmetic circuit (not shown), and the movement of the variator lens 422 is controlled based on the calculation result.

The system controller 61 controls the focusing encoder 59 via the lens controller 58.
The output of A (the feed amount Ed) and the output of the zooming encoder 60A (the zoom step value fp) are read. Inside the system controller 61, a distortion table T1, a principal point position table T2, and an image distance table T3
, And the photographing condition data corresponding to the feeding amount Ed and the zoom step value fp are output to the host 2. The photographing condition data here includes a distortion aberration parameter (lens distortion correction coefficient d1, d2), a front principal point position FH, and an image distance b. The front principal point position FH is represented by the distance between the front end point F of the zoom unit 51 and the front principal point H. Since the front end point F is fixed, the front principal point H can be specified by the front principal point position FH.

The system controller 61 calculates the output (laser intensity) of the semiconductor laser 41 and the deflection conditions (scan start angle, scan end angle, deflection angular velocity) of the slit light U. This calculation method will be described in detail. First, assuming that a planar object exists at an approximate distance d ₀ between the objectives, the projection angle is set so that the reflected light is received at the center of the sensor 53. The pulse lighting for calculating the laser intensity described below is performed at the set projection angle.

Next, the laser intensity is calculated. When calculating the laser intensity, a human body may be measured, so safety considerations are indispensable. First, the minimum strength LDm
The pulse is turned on at “in”, and the output of the sensor 53 is captured. Captured signal [Son (LDmin)] and appropriate level S
Calculate the ratio with typ and set a temporary laser intensity LD1.

LD1 = LDmin × Type / MAX
[Son (LDmin)] Subsequently, the pulse is turned on again with the laser intensity LD1 and the sensor 5
Capture the output of # 3. Captured signal [Son (LD
If 1)] is an appropriate level Type or a value close thereto, LD1 is determined as the laser intensity LDs. In other cases, a temporary laser intensity LD1 is set using the laser intensity LD1 and MAX [Son (LD1)], and the output of the sensor 53 is compared with the appropriate level Styp. Until the output of the sensor 53 becomes a value within the allowable range, the temporary setting of the laser intensity and the confirmation of suitability are repeated. Note that the output of the sensor 53 is captured for the entire imaging surface S2. this is,
This is because it is difficult to estimate the light receiving position of the slit light U with high accuracy in passive distance calculation by AF. The integration time of the CCD in the sensor 53 is one field time (for example, 1/60 second), which is longer than the integration time at the time of actual measurement. Therefore, by performing pulse lighting, a sensor output equivalent to that at the time of measurement is obtained.

Next, the distance d between the objects is determined by triangulation from the projection angle and the light receiving position of the slit light U when the laser intensity is determined. Finally, the determined objective distance d
The deflection condition is calculated based on. In calculating the deflection condition, the offset doff in the Z direction (see FIG. 24) between the rear principal point H ′ of the light receiving system, which is the reference distance measuring point for the object distance d, and the projection start point A is considered. Further, in order to secure the same measurable distance range d 'as that at the center in the scanning direction, an overscan of a predetermined amount (for example, for 8 pixels) is performed. Scan start angle th1, scan end angle th
2. The deflection angular velocity ω is expressed by the following equation.

Th1 = tan ⁻¹ [β × pv (np / 2 +
8) + L) / (d + doff)] × 180 / π th2 = tan ⁻¹ [−β × pv (np / 2 + 8) + L)
/ (D + doff)] × 180 / π ω = (th1−th2) / np β: imaging magnification (= d / effective focal length freal) pv: pixel pitch np: effective number of pixels in the Y direction of the imaging surface S2 L: base line Length Next, the main emission is performed under the conditions calculated in this manner, the object Q is scanned (slit projection), and the measurement data (slits) for five frames per pixel obtained by the output processing circuit 52 is obtained. Image data) D62 is sent to the host 2. At the same time, device information D10 indicating the deflection condition (deflection control data) and the specifications of the sensor 53 are also transmitted to the host 3.
Sent to

As shown in FIG. 10, in the host 3, the slit gravity center calculation # 31, distortion correction calculation # 32, camera line-of-sight equation calculation # 33, slit plane equation calculation # 34, and three-dimensional position calculation # 35 is performed, whereby the three-dimensional position (coordinates X, Y, Z) of the 200 × 231 sampling points is calculated. The sampling point is the intersection of the camera's line of sight (a straight line connecting the sampling point and the rear principal point H ') and the slit plane (the optical axis plane of the slit light U irradiating the sampling point).

Next, the operation mode will be described. FIG. 12 is a diagram showing types of operation modes. Measurement (photographing) as a factor indicating the performance of the measurement system 1
Speed QS proportional to the reciprocal of the time required for measurement, and measurement range Q which is a dynamic range in the depth direction (Z direction)
There is an R, a resolution QD, a sensitivity QB, and a measurement area QB that is a dynamic range in the vertical direction (Y direction).

The performance is determined by the number of lines (the number of readout lines) GL of the effective light receiving area Ae and the entire line width (the readout line width) G of the effective light receiving area Ae.
W, a line interval GT which is a value obtained by dividing the line width GW by the number of lines GL, a shift number GS, and a slit light width GP (width w of the slit light U). When the line interval GT is set to “2”, reading may be performed every other line, or reading may be performed after adding two lines. If reading is performed after adding two lines, a high sensitivity mode is set.

Normally, when the number of lines GL decreases, the reading is performed at a high speed, so that the measuring speed QS increases. When the line width GW increases, the depth direction (Z direction)
, The measurement range QR is expanded. As the shift number GS decreases, the resolution QD increases.

The operation mode includes a standard mode, a high-speed mode, and a high-speed mode depending on which of the performance factors is prioritized.
There are a wide Z mode, a high sensitivity mode, a high resolution mode, and a high speed and wide Z mode. There are various variations in each operation mode.

Next, the operation of the measurement system 1, particularly the differences between the operation modes, will be mainly described. FIG. 13 is a flowchart showing an outline of the operation of the measurement system 1, and FIG. 14 is a flowchart showing a mode setting process.

In FIG. 13, first, an initial setting is performed (# 11). When an operation mode setting operation is performed, the operation mode is changed (# 12, # 13). When the measurement start operation is performed, the operation mode is set according to the operation (# 14, # 15). Thereafter, measurement is performed according to the set operation mode (# 16).

In FIG. 14, parameters corresponding to the operation mode set by the operation are read (# 2).
1). The read width (effective light receiving area A
e), the line interval GT, the number of shifts GS, and whether or not the mode is the high sensitivity mode, and those parameters are output to the driver 55 (# 22).

The parameter indicating whether or not the mode is the high sensitivity mode is used when reading is performed after adding two lines when the line interval GT is "2". Instead of outputting as a parameter, a signal indicating the type of operation mode may be output. In that case, it is necessary to perform conversion for performing an operation corresponding to the operation mode in the driver 55.

Based on the number of lines GL, the selector 621
c to 624c, the frame delay memory 621a to
624a or one of 621b to 624b is selected (# 23).

The width w of the slit light U depends on the operation mode.
And the scanning speed are set (# 24). In the case of the wide Z mode or the high-speed high-wide Z mode, the aperture is stopped down (# 2)
5). That is, in the wide Z mode or the high-speed high-wide Z mode,
The measurement distance range is wide, and it is necessary to focus over a wide range. By reducing the aperture, the depth of field is deepened, making it easier to focus.

These processes are performed by the system controller 61.
Done by Hereinafter, some typical examples of each operation mode will be described. The standard mode is a mode in which the measurement speed QS, the measurement range QR, the resolution QD, the sensitivity QB, and the measurement area QB are all set to a standard state. In the standard mode, as shown in FIG. 7, the number of lines GL is “32” and the line width GW is “3”.
2 ", the line interval GT is set to" 1 ", the shift number GS is set to" 1 ", and the slit light width GP is set to" 5 ". In standard mode, measurement speed QS, measurement range Q
R, resolution QD, sensitivity QB, and measurement area QB are all “1”. The other operation modes are named by focusing on superior performance in comparison with the performance of the standard mode.

The high-speed mode is an operation mode in which measurement is performed at high speed. In the high-speed mode, the number of lines GL is set to half of that in the standard mode, and the number of shifts GS is set to twice that in the standard mode. Further, there are a case where the line width GW is kept in the standard mode and a case where the line width GT is set to “2” by setting the line width GW to half of the standard mode.

When the number of lines GL is reduced, the reading time of the received light data for one frame is shortened. Therefore, the period of shifting the frame can be shortened,
Measurement time for the entire screen is reduced. Also, when the number of shifts GS is increased, the number of frames for measuring the entire screen is reduced, so that the time for measuring the entire screen is reduced. In any case, the effective light receiving area Ae
Move at high speed, the slit light U also needs to move at high speed.

Depending on the combination of the number of lines GL and the number of shifts GS, as shown in FIG.
There are five high-speed modes. By setting the parameters appropriately, other high-speed modes can be set.

FIG. 15 shows the sensor 53 in the high-speed mode 1.
FIG. 16 shows an effective light receiving area Ae (read range) of FIG.
FIG. 17 is a diagram showing the effective light receiving region Ae in the high speed mode 2, FIG. 17 is a diagram showing the effective light receiving region Ae in the high speed mode 3, and FIG.

In the high-speed mode 1 shown in FIG. 15, the number of pixels in the shift direction of the effective light receiving area Ae is "16".
The scanning speed of the slit light U is controlled to be twice that of the standard mode. The high-speed mode 1 has the following features compared to the standard mode.

Readout time: 1/2 (measurement speed is twice) Measurement range: 1/2 Resolution: same That is, the high-speed mode 1 is effective when emphasizing the resolution QD rather than the measurement range QR.

In the high-speed mode 2 shown in FIG. 16, the line width GW of the effective light receiving area Ae, that is, the width of the pixel in the shift direction is “32”, but the line interval GT is “2”, and Since we skipped reading, the number of lines GL,
That is, the number of pixels of the received light data is “16” which is half of the number of pixels.
Becomes The slit light width GP in the high-speed mode 2 is “1”.
0 ", but half of them are skipped,
The received light data is for five pixels. The high-speed mode 2 has the following features compared to the standard mode.

Readout time: 1/2 Measurement range: Same resolution: 1/2 That is, high-speed mode 2 is effective when the measurement range QR is more important than the resolution QD.

In the high-speed mode 3 shown in FIG. 17, the number of lines GL and the line width GW of the effective light receiving area Ae are both "32", but the number of shifts GS is "2", and the effective light receiving area Ae has two lines. Shift one by one. As a result, the number of input frames is reduced, and the overall measurement time is reduced. The amount of movement of the slit light U is also controlled to be two lines for one frame. High-speed mode 3
Has the following features compared to the standard mode.

Read time: 1/2 Measurement range: Same Resolution: 1/2 In the high-speed mode 4 shown in FIG. 18, the effective light receiving area Ae
The line number GL and the line width GW are both “32” and the shift number GS is also “1”. However, the measurement is not performed over the entire imaging surface S2 of the sensor 53, but the measurement is performed only on a part of them. Do. Therefore, the measurement area QB becomes narrow. The scanning range of the slit light U is also adjusted to this. Assuming that the number of frames in the standard mode is N, the number of frames in the high-speed mode 4 is N ′, and R = N ′ / N, the features of the high-speed mode 4 with respect to the standard mode are expressed as follows using this R. You.

Readout time: R Measurement range: Same resolution: Same measurement area: R To realize the high-speed mode 4, in step # 22 of the flowchart shown in FIG. 14, the start frame number and the end frame The number and the number are output to the driver 55, and the scanning start position and the scanning end position of the slit light U are set.

Next, the wide Z mode will be described. Hiro Z
The mode is an operation mode in which the measurement range in the depth direction is expanded. In the wide Z mode, the line width GW is set to twice that in the standard mode.

FIG. 19 is a view showing the effective light receiving area Ae in the wide Z mode 1, and FIG. 20 is a view showing the effective light receiving area Ae in the wide Z mode 2. Wide Z mode 1 shown in FIG.
, The line width GW of the effective light receiving area Ae is “64”
However, since the reading is skipped for each pixel, the number of pixels of the received light data is “32”. The slit light width GP in the wide Z mode 1 is “10”, but half of the slit light width GP is skipped, so that light reception data is equivalent to five pixels. The wide Z mode 1 has the following features compared to the standard mode.

Readout time: Same Measurement range: 2 times Resolution: 1/2 That is, the wide Z mode 1 is effective when it is desired to widen the measurement range QR.

In the wide Z mode 2 shown in FIG. 20, the number of lines GL and the line width GW of the effective light receiving area Ae are “6”.
4 ", which is twice the standard mode. The scanning speed of the slit light U is half that of the standard mode. The wide Z mode 2 has the following features compared to the standard mode.

Readout time: 2 times Measurement range: 2 times Resolution: Same Next, the high sensitivity mode will be described. The high sensitivity mode is an operation mode in which the sensitivity of the sensor 53 is increased.

FIG. 21 shows the effective light receiving area Ae in the high sensitivity mode. In FIG. 21, the line width GW of the effective light receiving area Ae is “32”. However, since the line width GW is added every two pixels, the number of lines GL, that is, the number of pixels of light receiving data is “16”. Slit light width G in high sensitivity mode
Although P is “10”, since two pixels are added, light reception data is five pixels. The scanning speed of the slit light U is twice that of the standard mode. The high sensitivity mode has the following features compared to the standard mode.

Reading time: 1/2 Measurement range: Same Resolution: 1/2 Sensitivity: 2x Next, the high resolution mode will be described. The high resolution mode is an operation mode in which the resolution is increased.

FIG. 22 is a diagram showing the effective light receiving area Ae in the high resolution mode. In FIG. 22, the number of lines GL and the line width GW of the effective light receiving area Ae are both “3”.
2 ", but the shift number GS is 1/2. That is,
The scanning speed of the slit light U is 1/2 of the standard mode,
The frame shift is one pixel for reading two frames. Since data is read each time the slit light U moves half the pixel pitch pv, the slit light U
Can be detected with twice the accuracy of passing through the pixel. The high resolution mode has the following features compared to the standard mode.

Readout time: 2 times Measurement range: Same resolution: 2 times To realize the high resolution mode, in Step # 22 of the flowchart shown in FIG. 14, it is set so that one pixel is moved for reading out two frames. Then, in step 24, it may be set so that one pixel is read out by moving a half pixel. The selection of the frame delay memories 621a to 624a in the output processing circuit 62 is the same as in the standard mode.

The control of the number of lines GL, the line width GW, and the number of shifts GS of the effective light receiving area Ae of the sensor 53 is performed by the system controller 61 outputting an instruction signal corresponding thereto to the driver 55. Will be
The control of the scanning speed (deflection speed) of the slit light U is performed by the system controller 61 outputting an instruction signal to the drive system 46 to drive the galvanomirror 43. By changing the type or position of the variator lens 422 or the collimator lens 421, the width w of the slit light U can be changed to the imaging surface S2 of the sensor 53.
The above is switched to 5 pixels and 10 pixels.

According to the above-described embodiment, when it is desired to reduce the measurement time by switching the operation mode,
If you want to increase the measurement depth, increase the resolution,
Measurement can be performed for various purposes, such as when it is desired to increase the sensitivity. In such a case, the measurement time may be longer, the depth of the measurement may be narrower, the resolution may be lower, or the measurement area may be smaller. Various settings can be made in light of the conditions.

In the above embodiment, the three-dimensional camera 2
The sharing of functions between the host and the host 3 can be changed in various ways. Alternatively, the functions of the host 3 may be integrated by incorporating the function of the host 3 into the three-dimensional camera 2. In the above embodiment, the case where the slit light U is scanned has been described. However, the present invention can be applied to the case where the spot light is two-dimensionally scanned.

In the above-described embodiment, the setting contents of the operation mode, the combination contents, the configuration of the output processing circuit 62, the processing contents, the configuration of the whole or each part of the measuring system 1, the circuit, the processing contents, the processing order, and the processing timing The setting contents, setting values, and the like can be appropriately changed in accordance with the gist of the present invention.

[0091]

According to the present invention, a single three-dimensional measuring apparatus can be used for various purposes under various measuring conditions.

[Brief description of the drawings]

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

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

FIG. 3 is a block diagram illustrating a functional configuration of a three-dimensional camera.

FIG. 4 is a schematic diagram illustrating a configuration of a light projecting lens system.

FIG. 5 is a principle diagram of calculation of a three-dimensional position in the measurement system.

FIG. 6 is a block diagram of an output processing circuit.

FIG. 7 is a diagram showing a reading range of a sensor.

FIG. 8 is a diagram showing an example of a configuration in the case of interline transfer of a CCD area sensor.

FIG. 9 is a diagram showing a data flow in the three-dimensional camera.

FIG. 10 is a diagram showing a data flow in a host.

FIG. 11 is a diagram showing a relationship between each point of the optical system and an object.

FIG. 12 is a diagram showing types of operation modes.

FIG. 13 is a flowchart showing an outline of the operation of the measurement system.

FIG. 14 is a flowchart illustrating a mode setting process.

FIG. 15 is a diagram showing an effective light receiving area of the sensor in a high-speed mode 1.

FIG. 16 is a diagram showing an effective light receiving area in a high-speed mode 2.

FIG. 17 is a diagram showing an effective light receiving area in a high-speed mode 3;

FIG. 18 is a diagram showing an effective light receiving area in a high-speed mode 4.

FIG. 19 is a diagram showing an effective light receiving area in the wide Z mode 1.

FIG. 20 is a diagram showing an effective light receiving area in the wide Z mode 2;

FIG. 21 is a diagram showing an effective light receiving area in the high sensitivity mode.

FIG. 22 is a diagram showing an effective light receiving area in the high resolution mode.

FIG. 23 is a diagram showing an outline of a slit light projection method.

FIG. 24 is a diagram for explaining the principle of measurement by the slit light projection method.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Measurement system (three-dimensional measurement device) 23 Select button (means for selecting operation mode) 41 Semiconductor laser (irradiation means) 43 Galvano mirror (scanning means) 53 Sensor (light receiving sensor) 55 Driver (means for reading output signal) 61) System controller (means for switching scanning speed, means for switching line width, means for switching line interval, means for switching the number of shifts) Q Object (measurement target) U Slit light (reference light)

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Makoto Miyazaki 2-3-1-13 Azuchicho, Chuo-ku, Osaka-shi, Osaka Inside Osaka International Building Minolta Co., Ltd. (72) Inventor Eiichi Ide Azuchi, Chuo-ku, Osaka-shi, Osaka (3) Osaka International Building Minolta Co., Ltd. (72) Inventor Hiroshi Uchino 2-3-1-13 Azuchicho, Chuo-ku, Osaka-shi, Osaka Osaka International Building Minolta Co., Ltd. (72) Inventor Toshio Kaida Osaka International Building Minolta Co., Ltd. 2-3-1-13 Azuchicho, Chuo-ku, Osaka-shi, Osaka

Claims (6)

[Claims] A means for irradiating the measurement target with reference light; a means for scanning the reference light; a light receiving sensor for receiving light reflected by the measurement target of the reference light; Means for selecting an operation mode, comprising: a means for repeatedly driving a sensor to read an output signal; and a means for selecting an operation mode in a three-dimensional measuring apparatus for measuring a three-dimensional shape of a measurement target based on the output signal of the light receiving sensor. Means for switching the scanning speed of the reference light and the reading operation of the light receiving sensor in accordance with the operation mode set forth above. A means for irradiating the object to be measured with reference light; a means for scanning the reference light; a light-receiving sensor for receiving light reflected by the object for measurement of the reference light; Means for selecting an operation mode, comprising: a means for repeatedly driving a sensor to read an output signal; and a means for selecting an operation mode in a three-dimensional measuring apparatus for measuring a three-dimensional shape of a measurement target based on the output signal of the light receiving sensor. Means for switching a line width in reading of the light receiving sensor in accordance with the operation mode performed. A means for irradiating the object to be measured with reference light; a means for scanning the reference light; a light-receiving sensor for receiving light reflected by the object for measurement of the reference light; Means for selecting an operation mode, comprising: a means for repeatedly driving a sensor to read an output signal; and a means for selecting an operation mode in a three-dimensional measuring apparatus for measuring a three-dimensional shape of a measurement target based on the output signal of the light receiving sensor. Means for switching a line interval in reading out the light receiving sensor according to the operation mode set. 4. A means for irradiating the object to be measured with reference light, a means for scanning the reference light, a light-receiving sensor for receiving light reflected by the object for measurement of the reference light, and a light-receiving sensor for scanning the reference light. Means for selecting an operation mode, comprising: a means for repeatedly driving a sensor to read an output signal; and a means for selecting an operation mode in a three-dimensional measuring apparatus for measuring a three-dimensional shape of a measurement target based on the output signal of the light receiving sensor. Means for switching the scanning speed of the reference light, according to the selected operation mode, means for switching the line width in reading out the light receiving sensor, according to the selected operation mode, and according to the selected operation mode, Means for switching a line interval in reading of the light receiving sensor; and a three-dimensional measuring apparatus. 5. A means for irradiating a measurement target with reference light, a means for scanning the reference light, a light receiving sensor for receiving light reflected by the measurement target of the reference light, and a light receiving sensor for scanning the reference light. Means for selecting an operation mode, comprising: a means for repeatedly driving a sensor to read an output signal; and a means for selecting an operation mode in a three-dimensional measuring apparatus for measuring a three-dimensional shape of a measurement target based on the output signal of the light receiving sensor. Means for switching the line width of the effective light receiving area of the light receiving sensor and the line interval in reading according to the selected operation mode; and the number of line shifts per frame in reading by the light receiving sensor in accordance with the selected operation mode. A three-dimensional measuring apparatus, comprising: 6. The three-dimensional measuring apparatus according to claim 5, further comprising means for switching between skipping a line in the middle or adding a read output signal when the number of shifts is plural.