JPH06102026A - Three dimensional image input system - Google Patents

Abstract

PURPOSE:To allow accurate measurement of distance between a reference surface and the surface of an object to be measured by regulating the transmissivity of a filter means disposed on an optical path based on a detected data. CONSTITUTION:A liquid crystal filter 12 is disposed on the optical path A of the bundle of scattered rays, i.e., it is interposed between an object 2 to be measured and a fixed mirror 10'. When the peak value of detection data from a signal processing section 5, i.e., pixel data from a one-dimensional image sensor CCD, is larger than a preset first threshold value, an output regulating means 13 makes a decision that the detection data is affected by the shape or the surface conditions of the object or the incident angle of the bundle of measuring rays and lowers the transmissivity (applying voltage) of the filter 12 such that the data representative of the peak value is not saturated. When the peak value is lower than a second threshold value (lower than the first threshold value), incident quantity of scattered light to means 9, 11 for detecting the bundle of scattered light is low, and thereby the transmissivity of the filter 12 is increased thus increasing the output of the detecting means 9, 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light source, an irradiation means for irradiating a measuring light beam from the light source toward a measuring object on a reference surface, and a scattered light beam from the surface of the measuring object. A three-dimensional image comprising a scattered light flux detecting means and a signal processing unit for calculating and deriving the distance from the reference surface to the surface of the measuring object based on the detection data of the scattered light flux detecting means. Regarding the input device, for example, a CAD data input device for inputting an external shape from a molding die or a model of various designed products to finish a final design drawing, and a three-dimensional image material used for education or sales. The present invention relates to a three-dimensional image input device used as an input device, a medical diagnostic device, or a visual sensor of a robot.

[0002]

2. Description of the Related Art Conventionally, this type of three-dimensional image input device is
In order to detect a minute light flux incident on the scattered light flux detection means of the scattered light flux from the measurement object,
The detection accuracy is ensured by securing the intensity of the measurement light flux so as to obtain a predetermined output, or by amplifying the output of the photodetection element with a constant amplification factor. Here, a one-dimensional image sensor, a non-divided condensing position detecting element, or the like has been used as the light detecting element in the scattered light flux detecting means (Japanese Patent Application No. 3-168628).

[0003]

However, according to the above-mentioned prior art, the light flux incident on the scattered light flux detection means may be changed depending on the shape and surface condition of the object to be measured, the incident angle of the measurement light flux, and the like. It is possible that the intensity becomes larger than the expected value, and in such a case, the detection output by the scattered light flux detecting means is saturated, so that the accurate distance from the reference surface to the surface of the measurement target object. Could not be measured. For example, when a one-dimensional image sensor is used as the light detecting element, all of the adjacent pixels are saturated and the peak position cannot be detected accurately. Further, in the one configured to detect the surface color of the measurement object from the three-dimensional shape of the measurement object as well as the component ratio of each wavelength using a laser that outputs the three primary colors of RGB as the light source, When the state occurs, it is difficult to detect the color of the object accurately. An object of the present invention is to eliminate the above-mentioned conventional drawbacks.

[0004]

In order to achieve this object, the first characteristic configuration of the three-dimensional image input apparatus according to the present invention is such that a filter means having an adjustable transmittance is provided for the measurement light beam bundle or the scattered light beam bundle. An output adjusting means is provided in the optical path for adjusting the output of the scattered light flux detecting means by adjusting the transmittance of the filter means based on the detection data. And the second characteristic configuration is provided with output adjusting means for adjusting the output of the scattered light flux detecting means by adjusting the intensity of the measuring light flux output from the light source based on the detection data. In point. A third characteristic configuration is that an output adjusting means for adjusting the output of the scattered light flux detecting means based on the detection data is provided.

[0005]

In the three-dimensional image input device according to the present invention,
Output data of the scattered light flux detection means, or from the incident light amount of the scattered light flux to the scattered light flux detection means back calculated from the output data of the scattered light flux detection means, indirectly, the shape or surface state of the measurement object, or The influence of the incident angle of the measurement light bundle is detected and the output is adjusted so as not to saturate. That is, according to the first characteristic configuration, if the amount of light incident on the scattered light flux detection means is small, the transmittance of the filter means is increased to increase the output of the scattered light flux detection means, and If the amount of incident light is large, the transmittance of the filter means is increased to reduce the output of the scattered light flux detection means to a level at which it is not saturated. According to the second characteristic configuration,
If the amount of incident light to the scattered light flux detecting means is small, the intensity of the measuring light flux output from the light source is increased to increase the output of the scattered light flux detecting means, and the amount of incident light to the scattered light flux detecting means is large. If so, the intensity of the measurement light flux output from the light source is reduced to reduce the output of the scattered light flux detection means.
According to the third characteristic configuration, if the amount of incident light to the scattered light flux detecting means is small, the output of the scattered light flux detecting means is increased by the output adjusting means, and the amount of incident light to the scattered light flux detecting means is large. If so, the output adjusting means lowers the output of the scattered light flux detecting means. Here, as the output adjusting means, for example, when a CCD image sensor is used as the light detecting element, a means for adjusting the charge accumulation time can be considered.

[0006]

Therefore, according to the present invention, the intensity of the light incident on the scattered light flux detecting means varies greatly depending on the shape and surface condition of the object to be measured, the incident angle of the measurement light flux, and the like. Also, it is possible to accurately measure the distance from the reference surface to the surface of the measurement object, using a laser that outputs the three primary colors of RGB as the light source, the three-dimensional shape of the measurement object together with the component ratio of each wavelength from the measurement object A three-dimensional image input device capable of accurately detecting the color of an object can be provided even if the surface color is also detected.

[0007]

EXAMPLES Examples will be described below. As shown in Figure 1,
The three-dimensional image input device includes a reference plane 1 on an XY plane,
A measuring unit 3 for irradiating the measuring light beam 2 placed above it on the reference plane 1 with the measuring light beam and detecting a scattered light beam from the surface of the measuring object 2, and the measuring unit. The measurement control unit 4 for controlling the measurement operation of the measurement unit 3;
The signal processing unit 5 for calculating and deriving the distance in the Z direction from the reference plane 1 to the surface of the measurement target 2 based on the measurement data according to, and the measurement target 2 from the three-dimensional data derived by the signal processing unit 5. It is composed of a model generation unit 6 for reconstruction.

The measuring unit 3 includes a light source 8 composed of a laser and an X light source.
A light receiving element 9 composed of a one-dimensional image sensor CCD arranged along the axial direction is arranged so as to be opposed to each other with a scanning mirror 7 interposed therebetween, and a measuring light flux from the light source 8 is transmitted to the scanning mirror 7.
And an optical head which irradiates the measuring object 2 via the fixed mirror 10 and guides the scattered light flux from the surface of the measuring object 2 to the light receiving element 9 via the fixed mirror 10 'and the scanning mirror 7. It is composed of a scanning mechanism (not shown) that performs scanning in the Y-axis direction by moving the optical head in the Y-axis direction.

The measurement control unit 4 includes the scanning mirror 7
Is rotated about an axis parallel to the Y-axis, and the measurement light beam from the light source 8 is passed through the reference plane 1 including the object 2.
And irradiate the same with the scattered ray bundle, and the fixed mirror 10 'and the scanning mirror 7
The scanning mechanism scans the optical head in the Y-axis direction while guiding the light to the light receiving element 9 via the condenser lens 11. That is, the measurement unit 3 and the measurement control unit 4 constitute an irradiation unit that irradiates the measurement light beam from the light source 8 toward the measurement object 2 on the reference surface 1, and the measurement light beam from the light source 8 is emitted. A scanning means for scanning the object 2 on the reference plane 1 at a set scanning density is configured, and the condenser lens 11 and the light receiving element 9 detect a scattered light flux from the surface of the object 2 to be measured. The scattered light flux detecting means is configured.

The signal processing unit 5 is provided with the light receiving element 9 in front.
The position to detect the scattered light flux from the reference plane 1 and
The deviation from the detected position for the current scattered ray bundle and the previous
From the rotation angle of the scanning mirror 7, whether the reference plane 1
The surface position of the measurement object 2 is calculated and derived. That is, the figure
As shown in 2, the distance X detected by the CCD₀X₁But Δ
X₀And that the object to be measured from the reference plane 1 is
Surface position of object 2 Z₀But Z₀× θ = ΔX ₀Have a relationship
Because of that, Z₀Ask for. The model generation unit 6 has an X direction.
Measurement points obtained by scanning in the Y direction and scanning in the Y direction.
The value in the Z direction for the into (determined by the scanning density)
The specified XYZ coordinate data is used as three-dimensional image data.
Then, from them, the shape of the measuring object 2 is displayed on the computer.
Reproduce.

A liquid crystal filter 12 is provided between the optical path A of the scattered light flux, that is, the object to be measured 2 and the fixed mirror 10 '.
And an output adjusting means 13 for adjusting the outputs of the scattered light flux detecting means 9 and 11 by adjusting the transmittance of the liquid crystal filter 12 based on the detection data by the scattered light flux detecting means. is there. More specifically, the output adjusting unit 13 is configured to detect the detection data obtained from the signal processing unit 5, that is, the one-dimensional image sensor CCD.
Compare whether the data showing the peak value of the pixel data of is larger than the preset first threshold value or smaller than the second threshold value smaller than the first threshold value. If the data indicating the peak value is larger than the first threshold value, it is determined that there is an influence of the shape or surface condition of the measurement object or the incident angle of the measurement light beam, and the peak is detected. Adjust so that the data showing the values are not saturated. That is, if the peak value is smaller than the second threshold value, the amount of light incident on the scattered light flux detection means is small, so the transmittance of the liquid crystal filter 12 is increased (the applied voltage is increased).
While increasing the output of the scattered light flux detecting means, if the peak value is larger than the first threshold value, the amount of light incident on the scattered light flux detecting means is large, so the transmittance of the liquid crystal filter 12 is lowered (applied). By lowering the voltage (by lowering the voltage) to a level that does not saturate the output of the scattered light flux detection means, large fluctuations in the detection data by the scattered light flux detection means are avoided along the scanning direction. That is, the liquid crystal filter 12 serves as a filter unit whose transmittance can be adjusted.

Another embodiment of the present invention will be described below. Although the liquid crystal filter 12 is provided between the measurement object 2 and the fixed mirror 10 'in the above embodiment, the location of the liquid crystal filter 12 is not limited to this, and the light source 8 receives light. It is optional as long as it is between the elements 9.

In the above embodiment, the liquid crystal filter 12 is used as the filter means with adjustable transmittance, but the invention is not limited to this. For example, if the scanning speed is slow, it may be possible to employ a mechanical diaphragm mechanism or a shutter mechanism.

In the above embodiment, the light source using a monochromatic laser beam has been described. However, the light source is not limited to this, and a light source combining three wavelength lasers corresponding to the three primary colors RGB of light is used. It may be color compatible.

In the above embodiment, the filter means having adjustable transmittance is provided in the optical path of the measurement light beam or scattered light beam, and the transmittance of the filter device is adjusted based on the detection data. Although the one having the output adjusting means for adjusting the output of the scattered light flux detecting means has been described,
In addition to the above, an output adjusting means 13 for adjusting the outputs of the scattered light flux detecting means 9 and 11 by adjusting the intensity of the measurement light flux output from the light source based on the detection data, An output adjusting means 13 for adjusting the outputs of the scattered light flux detecting means 9 and 11 based on the detection data may be provided. The former variably adjusts the output of the light source 8 itself. If the peak value is smaller than the second threshold value, the amount of light incident on the scattered light flux detecting means is small, so the output of the light source 8 is reduced. When the peak value is higher than the first threshold value, the amount of light incident on the scattered light flux detection means is large, so the output of the light source 8 is decreased to lower the scattered light flux. The output of the bundle detecting means is lowered to a level at which it is not saturated. For the latter, for example, for a device using a CCD image sensor as the light receiving element 9, it is possible to variably adjust the charge storage time or variably adjust the amplification factor of the amplifier of the light receiving element 9. That is, if the peak value is smaller than the second threshold value, the amount of light incident on the scattered light flux detection means is small, so the charge accumulation time is increased or the amplification factor is increased to output the scattered light flux detection means. On the other hand, if the peak value is larger than the first threshold value, the amount of light incident on the scattered light flux detection means is large, so that the charge accumulation time is shortened or the amplification factor is lowered to reduce the scattered light flux detection means. The output is lowered to a level that does not saturate.

The configuration of the measuring unit 3 is not particularly limited and may be appropriately configured. For example, as shown in FIG. 3, the optical head scans the scanning light flux only and the scattered light flux is a light receiving element. It may be configured by a fixed optical system that leads to the optical axis 9, or a scanning mechanism that performs scanning in the Y-axis direction by moving the optical head in the Y-axis direction (this can be easily configured by using a motor and a pulley). 4), a rotatable reflection mirror is provided around a shaft plug parallel to the X-axis in order to scan the plane formed by the measurement light beam bundle and the reflected light beam bundle in the Y-axis direction, as shown in FIG. You may comprise.

It should be noted that reference numerals are added to the claims for convenience of comparison with the drawings, but the present invention is not limited to the configurations of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of a three-dimensional image input device.

FIG. 2 is an explanatory diagram showing the principle.

FIG. 3 is a configuration diagram of a main part showing another embodiment.

FIG. 4 is a configuration diagram of a main part showing another embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 reference surface 2 measurement object 3,4 irradiation means 5 signal processing section 8 light source 9,11 scattered light flux detection means 12 filter means 13 output adjustment means

Claims (3)

[Claims] 1. A light source (8), and irradiation means (3), (4) for irradiating a measurement light flux from the light source (8) toward a measurement object (2) on a reference surface (1). , Scattered light flux detecting means (9), (11) for detecting the scattered light flux from the surface of the measurement object (2), and the scattered light flux detecting means (9),
A three-dimensional image input device configured to include a signal processing unit (5) for calculating and deriving a distance from the reference surface (1) to the surface of the measurement object (2) based on the detection data of (11). By providing a filter means (12) with adjustable transmittance in the optical path of the measurement light beam or scattered light beam, and adjusting the transmittance of the filter means (12) based on the detection data. A three-dimensional image input device provided with output adjusting means (13) for adjusting the outputs of the scattered light flux detecting means (9), (11). 2. A light source (8), and irradiation means (3), (4) for irradiating a measuring ray bundle from the light source (8) toward an object to be measured (2) on the reference surface (1). , Scattered light flux detecting means (9), (11) for detecting the scattered light flux from the surface of the measurement object (2), and the scattered light flux detecting means (9),
A three-dimensional image input device configured to include a signal processing unit (5) for calculating and deriving a distance from the reference surface (1) to the surface of the measurement object (2) based on the detection data of (11). Output adjustment for adjusting the output of the scattered light flux detection means (9), (11) by adjusting the intensity of the measurement light flux output from the light source (8) based on the detection data. A three-dimensional image input device provided with means (13). 3. A light source (8), and irradiation means (3), (4) for irradiating a measuring ray bundle from the light source (8) toward an object to be measured (2) on the reference surface (1). , Scattered light flux detecting means (9), (11) for detecting the scattered light flux from the surface of the measurement object (2), and the scattered light flux detecting means (9),
A three-dimensional image input device configured to include a signal processing unit (5) for calculating and deriving a distance from the reference surface (1) to the surface of the measurement object (2) based on the detection data of (11). And output adjusting means (13) for adjusting the output of the scattered light flux detecting means (9), (11) based on the detection data.
A three-dimensional image input device provided with.