JP3871115B2 - Shape measuring device, document scanner and projector - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an optical shape measuring device, a document scanner, and a projector for measuring the shape and distance of an object.
[0002]
[Prior art]
In a shape measuring device that measures the three-dimensional shape of an object, the object to be measured is irradiated with a slit-shaped laser beam, and the object is observed from a different field of view from the irradiation direction of the slit light while scanning perpendicularly to the longitudinal direction of the slit. There is one that measures the deformation of the slit light according to the object shape generated as described above as a shape using the principle of triangulation (hereinafter referred to as “light cutting method”).
[0003]
For example, as shown in FIG. 16, a light cutting method using an irradiation optical system by a semiconductor laser unit 101, a galvanometer mirror 102 and a cylindrical lens 103, and a detection optical system by an imaging lens 104 and a CCD 105 as a light receiving element is used. The shape measuring apparatus used is often used for industrial purposes.
[0004]
The light emitted from the semiconductor laser unit 101 in the form of a beam is scanned by the galvanometer mirror 102 in the horizontal direction of the drawing, is enlarged in the vertical direction by the cylindrical lens 103, and is irradiated to the measurement object 107 as a vertically long slit light 106. The At this time, when the reflected light 108 reflected from the measurement object 107 through the imaging lens 104 is observed by the CCD 105 from the direction in which the slit light 106 is scanned, that is, shifted from the base line direction, the depth of the measurement object 107 is measured. The linear slit light 106 is deformed and the imaging position is moved on the CCD 105 according to the unevenness. Observing the image of the reflected light 108 with the CCD 105 means that the position of each point of the measurement object 107 where the reflected light 108 enters the imaging lens 104 is triangulated, and the position where the slit light 106 is irradiated. If the position difference (baseline length) in the baseline direction of the CCD 105 is known in advance, the shape of the measurement object 107 in the portion irradiated with the slit light 106 can be measured from this deformation. By vibrating the galvanometer mirror 102 in the direction indicated by the arrow, the shape of the entire measurement object 107 can be obtained by repeating the shape measurement while scanning the slit light 106 over the entire surface of the measurement object 107.
[0005]
The principle of triangulation will be described in more detail with reference to FIG. 17 (see, for example, Toru Yoshizawa, “Optical three-dimensional measurement”, pp. 29-30, New Technology Communications, 1993). Assume that the slit light source 111 (corresponding to the reflection position of the beam light of the galvano mirror 102 in FIG. 16) and the light receiver 112 (corresponding to the CCD 105 in FIG. 16) are separated by the base line length L. If the light emitted from the slit light source 111 at an angle θ is reflected by the surface of the measurement object 113 at the position 113a and is incident at an angle φ on the position of the light receiver 112 to form an image, the relationship of equation (1)
Za = {tanθ * tanφ / (tanθ + tanφ)} * L (1)
Holds. If the distance d between the imaging lens 114 and the light receiver 112 and the distance Za of the measurement object in the vertical direction from the baseline length L are known in advance, the incident angle φ can be obtained. If the measurement object 113 is at the position 113b, assuming that the image is shifted by x with respect to the image formation position at the light receiver 112, Ψ can be found from the relationship of Ψ = arctan (x / d). (2) Relation of formula
Za = {tanθ * tan (φ + Ψ) / (tanθ + tan (φ + Ψ))} * L (2)
To obtain the distance Zb. If the slit light is scanned at the radiation angle θ so as to irradiate the entire surface of the measurement object 113 and the above procedure is repeated for each radiation angle θ, the distance Z between the reflection point and the base line of the measurement object 113, that is, the shape is Desired.
[0006]
As described above, the disadvantage of the light cutting method that sequentially scans the slit light on the measurement object requires an optical scanning optical system that scans each slit light, and usually a movable part such as the galvanometer mirror 102 in FIG. 16 is used. Therefore, it becomes weak to the vibration of the apparatus and it is necessary to repeat the shape measurement for each radiation angle θ, so that the measurement time is long. In addition, the amount of light observed by the light receiver 112 varies depending on the reflectance of the surface of the measurement object 113, and where the image of the measurement object 113 is formed in the light receiver 112 is the maximum of the amount of image formation light. It is necessary to estimate from the value or the like.
[0007]
There is a pattern light projection method as a shape measurement method that improves the disadvantage of the light cutting method that it is necessary to sequentially scan the slit light. In this method, instead of scanning the slit light, the entire slit light is arranged on the surface, and the measurement object is collectively irradiated as one pattern light. However, since it is not known which position of the pattern light corresponds to which slit light as it is, information about the correspondence with the slit light by some method in advance, that is, at which irradiation angle was irradiated, is used for information on the pattern light itself. Add (index).
[0008]
As one type of such pattern light projection method, there is a method (hereinafter referred to as “rainbow method”) in which a spectral spectrum pattern is collectively projected onto a measurement object. This method is disclosed in, for example, Japanese Patent Laid-Open No. 61-75210, and will be described with reference to FIG.
[0009]
The light transmitted from the light source 121 through the slit 122 is irradiated with a rainbow-like light pattern so as to be dispersed by the prism 123 and cover the surface of the object 124. Since the distribution of the color depending on the radiation angle α is determined by the arrangement of the prism 123 and the slit 122, an image in which the light reflected from the surface of the object 124 is imaged on the imaging surface 126 by the lens 125 is captured by the camera 127. The incident light β can be determined from the observed color. In other words, it is indexed with the color of the pattern light.
[0010]
Since the light source 121 and the camera 127 are separated by a distance D, if the radiation angle α is known, the surface shape of the object 124 can be obtained from the information by triangulation. The color is identified by changing the transmission wavelength of the filter 128 to obtain the light quantity ratio of two kinds of wavelengths of the reflected light at each point on the surface of the object 124. In other words, it can be considered that the two patterns of the intensity ratio method shown in the following example are superposed at different wavelengths, so they are members of the intensity ratio method.
[0011]
In this method, it is not necessary to sequentially scan the slit light unlike the light cutting method, and the rainbow-like light is projected onto the measurement object at once, and the reflection pattern is taken in with the color camera, so the slit light is scanned. There is no mechanically fragile movable part, and the shape measurement time can be shortened.
[0012]
On the other hand, since the radiation direction β of the irradiation light is determined by taking the ratio of the reflected light of the two wavelengths by the filter 128, the accuracy in the depth direction of the shape data is lowered if this accuracy is low. In order to improve the measurement accuracy of reflected light, it is necessary to make the S / N sufficiently high with respect to the amount of reflected light as signal light with respect to the amount of background light as noise. If the transmission wavelength width of the filter 128 is narrowed, it is possible to eliminate the influence of background light, but the signal light is also reduced at the same time, so that the S / N is limited, that is, the resolution is limited. Become. Furthermore, when the measurement object is colored, there is a problem that light other than the color is not easily reflected and the shape cannot be measured.
[0013]
As another pattern light projection method, there is an intensity ratio method (B. Carrihill and R. Hummel, “Experiments with the Intensity Ratio Depth Sensor”, Computer Vision, Graphics, and Image Processing, vol. 32, pp. 337-358, 1985 or Japanese Patent Laid-Open No. 10-48336).
[0014]
This intensity ratio method will be described with reference to FIG. The left-right direction in FIG. 19 is the baseline direction, and the pattern light source 131 (corresponding to the slit light source 111 in FIG. 17) and the light receiver 132 (corresponding to the light receiver 112 in FIG. 17) are the same as in the case of FIG. Are in different positions. The pattern light source 131 emits a planar light pattern that simultaneously irradiates the entire measurement surface 133 having a light quantity distribution with respect to the baseline direction. Assuming that the intensity distributions of the two light patterns with respect to the radiation angle θ are G1 (θ) and G2 (θ), each of the intensity distributions G1 (θ) and G2 (θ) has a reflectance σ having a measurement surface 133. When the light amounts reflected by the points and received by the light receiver 132 are P1 and P2, and the light amount of the pattern light source 131 is S, the relationship of equations (3a) and (3b)
P1 = K * σ * G1 (θ) * S (3a)
P2 = K * σ * G2 (θ) * S (3b)
Holds. Here, K is a coefficient determined from the positional relationship between the pattern light source 131, the light receiver 132, and the measurement surface 133. The reflectance σ of the measurement surface 133 depends on the characteristics of the surface of the measurement surface 133 and cannot be determined in advance. However, when the ratio of the equations (3a) and (3b) is taken, the relationship of the equation (4)
P2 / P1 = G2 (θ) / G1 (θ) (4)
Thus, it can be seen that the ratio of P2 and P1 depends only on the radiation angle θ. That is, the indexing is performed by the ratio of the light intensity of the two pattern lights. By irradiating the measurement surface 133 with an optical pattern having two intensity distribution lights G1 (θ) and G2 (θ) and measuring P2 / P1, θ can be uniquely obtained with respect to the radiation angle θ. As shown in FIG. 16, it is not necessary to sequentially detect the amount of light by the CCD while scanning the slit light with respect to the base line direction, and it is sufficient to observe the image of the CCD with respect to the two pattern lights. There is an advantage that is shortened. However, G2 (θ) / G1 (θ) needs to be a monovalent function with respect to θ. For example, if G1 (θ) is a monotone decreasing function with respect to θ and G2 (θ) is a monotone increasing function with respect to θ, G2 (θ) / G1 (θ) is a monotonically increasing function with respect to θ. Θ is uniquely obtained from P2 / P1.
[0015]
Incidentally, the above-mentioned B.I. In Carrihill's paper example, G1 (θ) has a uniform distribution regardless of θ, and G2 (θ) has a distribution in which the amount of light increases linearly, whereas in the example of Japanese Patent Laid-Open No. 10-48336, , G1 (θ) is a linearly decreasing distribution and G2 (θ) is a linearly increasing distribution, but the two radiation patterns only need to be monotonous. There is no significant difference.
[0016]
As described above, the intensity ratio method has an advantage in that it can be measured by irradiating two patterns at a time without depending on the reflectance of the measurement surface, but has a drawback as well. The problem with the intensity ratio method is that the reflected light amount, which is signal light, is sufficient with respect to the background light amount, which is noise, in order to increase the S / N of the measurement when taking the ratio of the light amount received by the light receiving element of the two light patterns. It is necessary to make it high. That is, if the minimum value of G1 (θ) or G2 (θ) is too small, the S / N is lowered, and the influence appears as a shape error. That is, the dynamic range of P2 / P1 does not increase. On the other hand, since there is a lower limit in the light amount resolution of the CCD, there is a lower limit in the resolution of the radiation angle θ that can be measured, resulting in a problem that the resolution of the measured shape is lowered.
[0017]
Further, the depth accuracy of the shape is determined depending on the S / N of the measured light quantity of the reflected light, as in the rainbow method shown in the previous example.
[0018]
[Problems to be solved by the invention]
The problems of the conventional example are summarized as follows.
[0019]
The light cutting method generally used for three-dimensional shape measurement requires an optical scanning optical system and has a problem that the measurement time is long.
[0020]
In the rainbow method, which is a type of pattern light projection method that has improved the problem, the radiation direction θ of the irradiated light is determined by taking the ratio of the reflected light of the pattern light of the two wavelengths. The measurement accuracy is limited and the accuracy is not so high.
[0021]
Similarly, in the intensity ratio method, which is a kind of pattern light projection method, the radiation direction θ of the irradiation light is determined by taking the ratio of two different reflected lights although the wavelength is the same. The accuracy is not so high.
[0022]
By the way, as another pattern light projection method, there is a proposal example of a region division intensity ratio method in which a measurement region is divided and pattern light is irradiated. This method will be described with reference to FIGS.
[0023]
Light emitted from the light sources 142a, 142b, and 142c incorporated in the illumination device 141 passes through the filters 143a, 143b, and 143c, is synthesized by the prism 144, and is irradiated onto the measurement object 145 as irradiation light 147. The reflected light 148 from the measurement object 145 is collected by the imaging lens 150 incorporated in the camera 149 and received by the color CCD 151.
[0024]
The transmittance distribution characteristics in the parallax direction of the filter 143 are shown in FIG. 21B and 21C, the measurement area A of the measurement object 145 is divided into six partial areas A1, A2,...
[0025]
21 (a) for the combination of the light source 142a and the filter 143a, FIG. 21 (b) for the combination of the light source 142b and the filter 143b, FIG. 21 (c) for the combination of the light source 142c and the filter 143c, and the light sources 142b and 142c. The combination with the filters 143b and 143c is shown in FIG. 21D, and the measurement area A is irradiated with a light amount proportional to this. When the radiation patterns of FIGS. 21A and 21D are used, the light quantity data obtained from the color CCD 151 based on the principle of the intensity ratio method described above is input to the rough shape estimation device 152 using the reflected light quantity distribution at that time as input. Can be generated. Since this data was obtained by a normal intensity ratio method, the accuracy is not so high.
[0026]
Next, using the radiation patterns shown in FIGS. 21B and 21C, the intensity ratio method is applied to the six partial areas A1, A2,... Shape data at A2,..., A6 can be obtained. In the normal intensity ratio method, which of the six partial areas A1, A2,. Although it cannot be determined and the ambiguity of the partial area is generated, the rough shape determination can be performed for each pixel of the color CCD 151 because the approximate shape data is obtained here. The shape estimation device 153 can calculate the shape of the entire measurement region E without ambiguity of the region from FIGS. 21B and 21C and the schematic shape data.
[0027]
The good point of this area division intensity ratio method is that the radiation pattern shown in FIGS. 21B and 21C irradiates with a light amount distribution that changes abruptly with respect to the parallax direction, so that the detection accuracy of the light amount in the color CCD 151 is high. As a result, the shape measurement accuracy is improved. By increasing the change in the light quantity distribution with respect to the parallax direction, the same effect as that obtained by increasing the light quantity resolution of the color CCD 151 can be obtained. On the other hand, the reason why the accuracy is low in the normal intensity ratio method is that the light intensity change between the measurement points adjacent in the parallax direction is small because the entire measurement area is irradiated with pattern light with continuous light intensity change. Is the cause. However, since the measurement area A is divided into partial areas A1, A2,..., A6, the partial areas A1, A2,..., A6 must be determined. In combination, the ambiguity of the partial region determination is removed, and the number of light sources, the number of filters, and the number of photographing increases as compared with the case of only the normal intensity ratio method. In addition, there is a problem that it is difficult to determine which boundary part belongs to the boundary part between the partial areas A1, A2,.
[0028]
As described above, in the area division intensity ratio method with improved resolution of the intensity ratio method, the measurement accuracy is improved by applying the intensity ratio method to a plurality of partial areas. Instead, it is necessary to perform partial area determination. There is a problem that the device configuration tends to be somewhat complicated.
[0029]
An object of the present invention is to use a pattern light projection method that irradiates a light pattern onto a plurality of partial regions such as a region division intensity ratio method (this intensity ratio method includes a rainbow method). It is to clarify the separation between the partial areas and to remove the ambiguity of the partial area determination.
[0030]
In addition, an object of the present invention is to ensure that the partial area can be specified.
[0031]
Furthermore, the objective of this invention is providing the method of implement | achieving the said objective simply.
[0032]
Another object of the present invention is to make it possible to simply and reliably perform shape correction of a document scanner that reads a document with unevenness such as a book shape.
[0033]
It is another object of the present invention to correct the tilt of the projection screen of the projector so that correction can be easily performed so that the screen can be projected in a rectangular shape even on an obliquely arranged screen.
[0034]
[Means for Solving the Problems]
The shape measuring apparatus according to the first aspect of the present invention is divided into n slit-shaped partial areas Ai (i: 1 to n) which are divided perpendicularly to the parallax direction and do not overlap each other with the separation area Wi interposed therebetween. For each measurement area A consisting of a partial area number), for each area paired with each partial area Ai and separation area Wi 2 Illuminating means for illuminating the light pattern Pi described above, light receiving means for receiving the reflected light of the light pattern Pi illuminated on the measurement area A with a parallax to the illumination means specified, and reflected light received by the light receiving means The shape for estimating the shape data Si of the partial area Ai using the parallax between the illumination means and the light receiving means while leaving the ambiguity of the partial area number i regarding the partial area Ai based on the information of the light quantity Ri of An estimation means; Based on the information on the light amount Ri of the reflected light, the position of each separation area Wi is specified, and the position of the partial area Ai adjacent to the specified separation area Wi is specified. , For each partial area Ai The ambiguity of the partial area number i in the estimated shape data Si is removed for each partial area Ai. Of partial area number i Shape correction means for obtaining shape data Zi without ambiguity.
[0035]
Therefore, by providing the separation regions Wi between the partial regions Ai of the region division method, the partial regions Ai can be clearly separated from each other, and the abnormal value of the shape generated at the boundary of the partial regions Ai can be removed. Since the boundary of the partial area Ai disappears, an incorrect shape is not given.
[0036]
The shape measuring apparatus according to a second aspect of the present invention is divided into n pieces of slit-shaped partial areas Ai (i: 1 to n) which are divided perpendicularly to the parallax direction and do not overlap each other with the separation area Wi interposed therebetween. For each measurement area A consisting of a partial area number), for each area paired with each partial area Ai and separation area Wi 2 Illuminating means for illuminating the light pattern Pi described above, light receiving means for receiving the reflected light of the light pattern Pi illuminated on the measurement area A with a parallax to the illumination means specified, and reflected light received by the light receiving means The corresponding partial region aI is identified using the information on the light amount Ri of the reflected light from the separation region Wi in the information on the light amount Ri, and triangulation using the parallax between the illumination unit and the light receiving unit is performed. Shape calculation means for obtaining shape data Zi for each partial area Ai based on the principle.
[0037]
Therefore, by providing the separation areas Wi between the partial areas Ai of the area division method and simultaneously identifying the adjacent partial areas Ai from the information of the light pattern of the separation area Wi, the determination of the partial areas Ai of the area division method is simplified. Therefore, the shape can be measured easily with high accuracy.
[0038]
According to a third aspect of the present invention, in the shape measuring apparatus according to the second aspect, the width of the separation region Wi is different.
[0039]
Therefore, in the shape measuring apparatus according to the second aspect, since the width of the separation region Wi is changed for each separation region Wi, the partial region Ai adjacent to the separation region Wi can be easily determined.
[0040]
According to a fourth aspect of the present invention, in the shape measuring apparatus according to the second aspect, the light pattern in the separation region Wi includes a light stripe having a different amount of light for each separation region Wi.
[0041]
Accordingly, in the shape measuring apparatus according to the second aspect, since the light pattern in the separation region Wi includes light stripes having different light amounts for each separation region Wi, the partial region Ai adjacent to the separation region Wi can be easily determined.
[0042]
According to a fifth aspect of the present invention, in the shape measuring apparatus according to the fourth aspect, there are two types of the light patterns Pi, and the light quantity ratio of the light stripes in the separation region Wi between the two types of light patterns Pi is equal to each separation region Wi. It is set to be different for each.
[0043]
Therefore, in the shape measuring apparatus according to claim 4, since there are two types of patterns Pi and the light quantity ratio of the light stripes in the separation region Wi is different for each separation region Wi, the partial region Ai adjacent to the separation region Wi can be easily determined. Can be judged.
[0044]
According to a sixth aspect of the present invention, in the shape measuring apparatus according to the second aspect, the amount of light for each wavelength of the light stripe in the separation region Wi is different for each separation region Wi.
[0045]
Therefore, in the shape measuring apparatus according to the second aspect, the amount of light for each wavelength of the light stripe inside the separation region Wi is different for each separation region Wi, so that the partial region Ai adjacent to the separation region Wi can be easily determined.
[0046]
A seventh aspect of the present invention is the shape measuring apparatus according to the second aspect, wherein the light pattern in the separation region Wi includes a light stripe encoded for each separation region Wi.
[0047]
Therefore, in the shape measuring apparatus according to the second aspect, since the optical pattern including the optical stripe encoded for each separation region Wi is used, the partial region Ai adjacent to the separation region Wi can be easily determined.
[0048]
According to an eighth aspect of the present invention, in the shape measuring apparatus according to the second aspect, the light pattern in the separation region Wi is a pattern of a constant light amount distribution in which the light amount is different for each separation region Wi.
[0049]
Therefore, in the shape measuring apparatus according to the second aspect, since a constant light pattern having a different amount of light is used for each separation region Wi, the partial region Ai adjacent to the separation region Wi can be easily determined.
[0050]
According to a ninth aspect of the present invention, in the shape measuring apparatus according to the eighth aspect, there are two types of the light patterns Pi, and a constant light quantity ratio in the separation regions Wi of the two types of light patterns Pi is provided for each separation region Wi. Are set to be different.
[0051]
Therefore, in the shape measuring apparatus according to the eighth aspect, since a constant light pattern having a different light quantity ratio is used for each separation region Wi, the partial region Ai adjacent to the separation region Wi can be easily determined.
[0052]
According to a tenth aspect of the present invention, in the shape measuring apparatus according to the eighth aspect, a constant light amount ratio for each wavelength in the separation region Wi is different for each separation region Wi.
[0053]
Therefore, in the shape measuring apparatus according to the eighth aspect, since the constant light pattern in which the light amount ratio for each wavelength is different for each separation region Wi is used, the partial region Ai adjacent to the separation region Wi can be easily determined.
[0054]
A document scanner according to an eleventh aspect of the invention includes the shape measuring apparatus according to any one of the first to tenth aspects, wherein a measurement region is set using a document original as a measurement object.
[0055]
Accordingly, since the shape measuring apparatus according to any one of claims 1 to 10 having a high measurement accuracy and a simple configuration is provided, the shape correction of the document scanner for reading a document with unevenness such as a book shape can be simply and reliably performed. Yes.
[0056]
According to a twelfth aspect of the present invention, there is provided a projector according to any one of the first to tenth aspects, wherein a measurement region is set with a projection screen as a measurement object.
[0057]
Accordingly, since the shape measuring device according to any one of claims 1 to 10 having a high measurement accuracy and a simple configuration is provided, the tilt of the projection screen of the projector is corrected, and the projection screen arranged obliquely is projected into a rectangle. Correction that can be performed can be performed easily.
[0058]
DETAILED DESCRIPTION OF THE INVENTION
A first embodiment of the present invention will be described with reference to FIGS.
[0059]
First, the principle and outline of the present embodiment will be described with reference to FIG.
[0060]
In general, in the area division intensity ratio method, the measurement area A is divided into a plurality of partial areas Ai, and each partial area Ai is irradiated with a separate light pattern Pi. The boundary of the partial area Ai differs from the light pattern that is originally intended to be irradiated due to the positional deviation of the irradiation optical system and the bleeding of the pattern in the measurement area of the light pattern. Therefore, the result of passing through the shape estimation means and the shape correction means based on the light amount Ri obtained around the boundary of the partial area Ai becomes an abnormal value.
[0061]
Therefore, in the present embodiment, as shown in FIG. 1, it is divided perpendicularly to the parallax direction connecting the illumination means L and the light receiving means D, and the separation area Wi (i = 1 to n−1) is interposed between them. With respect to the measurement area A composed of n slit-shaped partial areas Ai (i: a natural number indicating a partial area number of 1 to n) that are not overlapped with each other, each partial area Ai and separation area Wi Illumination means L for illuminating one or more types of light patterns Pi for each paired area, light receiving means D for receiving reflected light of the light pattern Pi illuminated on the measurement area A, and reflection received by the light receiving means D Shape estimation means for estimating the shape data Si of the partial area Ai using the parallax between the illumination means L and the light receiving means D while leaving the ambiguity of the partial area number i regarding the partial area Ai based on the information on the light quantity Ri of the light G and estimated shape data S Is a shape correction unit C for the ambiguity is removed obtaining the shape data unambiguous for each partial area Ai of the partial area number i, the configuration with the.
[0062]
That is, the measurement area A is irradiated with the light pattern Pi irradiated from the illumination unit L as illumination light. The light pattern illuminates the measurement area A by dividing it into n parts, but the separation areas Wi (W1, W2,..., Wn−1) are arranged between the partial areas Ai (A1, A2,..., An) obtained by dividing the measurement area A into n parts. ) Makes it clear that the data corresponding to the separation area Wi is data that cannot be used for shape recovery. In other words, the reflected light of the partial area Ai is detected by the light receiving means D and used to obtain the shape in the measurement area A, but the shape is obtained even if the reflected light in the separation area Wi is detected by the light receiving means D. Not used for that. By providing the separation region Wi, an abnormal value of the shape generated at the end of the partial region Ai can be removed.
[0063]
Here, the separation region Wi needs to be distinguished from the partial region Ai by some method. Various methods are conceivable. For example, if light is not irradiated over the entire separation region Wi, it can be easily determined from the value of the light amount Ri detected by the light receiving means D. From the information on the light quantity Ri obtained by the light receiving means D, the shape estimating means G can detect an extremely small area as the separation area Wi and determine how far the partial area Ai can be measured for the shape. . For example, if the light receiving means D is a CCD, the separation area Wi and the partial area Ai are arranged in order with respect to the base line direction corresponding to the light receiving cells of the CCD. If the cell of the CCD is searched in the baseline direction, the range of the separation area Wi can be specified. Therefore, an estimated shape Si in which the ambiguity of the partial area Wi is left is obtained by the shape estimation means G for the remaining partial area Ai. The final shape data Zi can be obtained by the correction means C.
[0064]
Other methods for separating the partial region Ai and the separation region Wi include irradiating the entire separation region Wi with a constant light amount, changing the irradiation wavelength only in the separation region Wi, changing the light amount distribution in the separation region Wi, etc. However, the method is not limited as long as it can be distinguished from the partial region Ai. In particular, when a light pattern that monotonously increases (or decreases) in the base line direction is irradiated for each partial area Ai by the region division intensity ratio method, it decreases monotonously (or increases) in the reverse base line direction. ) The configuration of irradiating the light pattern is easy to detect because the change in the intensity ratio in the baseline direction is reversed only by the separation region Wi, and can be easily realized in designing the light pattern.
[0065]
According to such a method, the amount of light applied to the separation region Wi can be controlled simply by designing the light pattern Pi applied to the measurement region A. Therefore, the irradiation optical system itself by the illumination means L is the same as the region division intensity ratio method. There is an advantage that you can do with things.
[0066]
By providing the separation region Wi, the measurement region A is divided into the partial region Ai and the separation region Wi. Therefore, the width of the partial region Ai in which shape measurement is actually possible is reduced, so the width of the separation region Wi is necessary. It is desirable to minimize it. For example, the width around the boundary of the region of the light pattern to be irradiated may be set wider than a width that cannot actually be used for shape measurement.
[0067]
In any of the embodiments including the present embodiment, since it is assumed that the separation region Wi is detected by the light receiving means D, the measurement object placed in the measurement region A is an object having a smooth shape. It is desirable that the reflected light can be obtained anywhere. In addition, the configuration in which the separation region Wi is provided between the partial regions Ai can be applied as long as it is a pattern light projection method that irradiates a light pattern divided into a plurality of regions, and the application is not limited to the intensity ratio method. .
[0068]
Next, a more practical configuration example of the present embodiment based on such a principle and outline will be described with reference to FIGS.
[0069]
First, in FIG. 2, the illumination means L is the illumination device 1, the light receiving means D is the camera 2, the parallax direction is the horizontal direction of the drawing, the reflected light amount Ri is the light amount value received by the CCD 3 in the camera 2, and the shape estimating means G Corresponds to the shape estimation device 4, and the shape correction means C corresponds to the shape correction device 5. The illumination device 1 includes a flash light source 6 and a filter 7. The camera 2 includes an imaging lens 8 and a CCD 3. Here, n = 4, and the measurement area A is divided into four partial areas A1, A2, A3, and A4, and three separation areas W1, W2, and W3 are interposed.
[0070]
Illumination light 9 transmitted through the filter 7 illuminated from the back surface by the flash light source 6 is reflected by the measurement object 10 in the measurement area A, collected as reflected light 11 by the imaging lens 8 of the camera 2, and detected by the CCD 3. The Since the base line length L which is the distance between the flash light source 6 and the CCD 3 is known, and the light receiving angle ψ is known from the image formation position on the CCD 3, if the irradiation angle θ can be obtained by any method, the measurement object 10 can be obtained by the principle of triangulation. You can see the distance. In the present embodiment, the filter 7 is replaced, and two types of light patterns can be projected. For each light pattern, the amount of light received by the CCD 3 is light amount data. In the shape estimation device 4, the region is indefinite (the subregion Ai to which it belongs is not yet determined) from the light amount data, the base length L, the irradiation angle θ, and the light receiving angle ψ using the principle of triangulation and the principle of the intensity ratio method. The shape data Si with the ambiguity left is calculated. This is finally corrected by the shape correction device 5, and unambiguous shape data Zi is obtained.
[0071]
As shown in FIG. 3, the filter 7 has a concentration gradient in which the transmittance monotonously increases (or monotonously decreases) in the baseline direction divided into four so as to control the irradiation intensity with respect to the parallax direction in the horizontal direction of the drawing. The attached filter is illuminated by a thin flash light source 6 whose longitudinal direction is perpendicular to the parallax direction. By exchanging the filter 7, two light stripe patterns are irradiated. Since the filter 7 can be easily created, the cost can be reduced when a large amount is created. Further, illumination with the flash light source 6 that can be regarded as a point light source with respect to the parallax direction eliminates the need for the imaging lens of the illumination device 1 and is advantageous in terms of downsizing and cost reduction.
[0072]
Next, FIG. 4 shows an example of a light pattern irradiated on the measurement region A. For example, when two types of light patterns a and b as shown in FIGS. 4A and 4B are used, the irradiation angle θ is specified from the ratio of the light patterns a and b in each partial region Ai. From the principle of the law, the shape can be calculated for each partial area Ai. On the other hand, a separation region Wi where the transmittance of the filter 7 is zero, that is, the amount of light is zero on the measurement region A surface, is provided at the end of the partial region Ai. If there is no separation area Wi, the light pattern blur occurs when the light quantity changes of the light patterns a and b jump, and the shape data there is incorrect, but the received light quantity becomes zero as in this embodiment. By providing the separation region Wi, it is not necessary to calculate an incorrect shape in the separation region Wi. If necessary, even if the partial area Ai is close to the end of the separation area Wi, a shape error is likely to occur. Therefore, it is possible to perform processing in which the shape is not calculated for safety within a certain distance from the separation area Ai.
[0073]
In addition, when two types of light patterns c and d as shown in FIGS. 4C and 4D are used, no discontinuity occurs in the light amount change in the separation region Wi, and thus there is a blur of the light pattern. However, even when there is a sudden change in the amount of light, it is possible to reduce the influence of the light in the bright part around the dark part. However, in the combination of the light patterns c and d, it is impossible to determine where the separation area Wi is based on the light amount alone, but when the intensity ratio of the light patterns c and d is scanned in the baseline direction, the change in the intensity ratio between the partial area Ai and the separation area Wi. Therefore, the separation area Wi can be determined using this.
[0074]
A second embodiment of the present invention will be described with reference to FIGS. The same parts as those shown in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted (the same applies to the following embodiments in order).
[0075]
In the present embodiment, the area division intensity ratio method of the first embodiment is improved by removing the ambiguity of the determination of the partial area Ai, and the reflected light received by the light receiving means D is reduced. Triangulation using the parallax (baseline length) between the illumination means L and the light receiving means D by identifying the corresponding partial area Ai using the information on the light quantity Ri of the reflected light from the separation area Wi among the information on the light quantity Ri. On the basis of the above principle, shape calculation means G (shape calculation device 21) for obtaining shape data Zi for each partial area Ai is provided.
[0076]
That is, as in the case of the first embodiment, the separation regions Wi are arranged between the partial regions Ai of the light pattern of the region division intensity ratio method, but some different information is given to each light pattern Pi of the separation region Wi. By mounting, the separation area Wi is identified based on the information of the reflected light Ri, and the partial area Ai adjacent to the separation area Wi is identified.
[0077]
If the light receiving means D can detect the separation area Wi based on the information of the light amount Ri, it can be determined to what extent the separation area Wi is. If the light receiving means D is a CCD, the separation region Wi and the partial region Ai are arranged in order with respect to the base line direction corresponding to the light receiving cells of the CCD. If the CCD cell is searched in the base line direction, the range of the separation area Wi and the type of the separation area Ai can be specified, so the partial area Ai sandwiched between the specified separation areas Wi is determined. Since the partial area number i can be specified, the shape calculation means G (shape calculation apparatus 21) can apply the intensity ratio method to the information on the light amount Ri for the specified partial area Ai. An unambiguous shape Zi can be obtained for each region Ai.
[0078]
In the case of the present embodiment, the optical system configuration is advantageous in that the design of the light pattern Pi is different from that in the case of the first embodiment, and the irradiation optical system itself can be the same as the area division intensity ratio method. .
[0079]
Referring to FIG. 5, the illumination light 9 transmitted through the filter 7 illuminated from the back surface by the flash light source 6 is reflected by the measurement object 10 in the measurement region A and is reflected by the imaging lens 8 of the camera 2 as the reflected light 11. The light is collected and detected by the CCD 3. Since the base line length which is the distance between the flash light source 6 and the CCD 3 is known, and the light receiving angle ψ is known from the imaging position on the CCD 3, if the irradiation angle θ can be obtained by any method, the measurement object 10 can be obtained by the principle of triangulation. You can see the distance. The filter 7 is replaced, and two types of light patterns can be projected. For each light pattern, the amount of light received by the CCD 3 is light amount data.
[0080]
In the present embodiment, as shown in FIG. 6, since the widths of the irradiation angles of the separation regions W1, W2, and W3 are different for each region, the light amount data received by the CCD 3 in the shape calculation device 21 is the baseline direction. If the scanning is performed, the separation regions W1, W2, and W3 can be distinguished from each other. As a result, the partial areas A1, A2, A3, and A4 can be identified from the position of the separation area Wi, and the intensity ratio obtained from the light quantity data and the shape data without ambiguity from the partial area Ai to which the light quantity data belongs. Can be obtained.
[0081]
As a result, the problem that the partial region Ai to which the region division intensity ratio method belongs is ambiguous is solved. Since there is no need to estimate the partial area Ai, it is only the shape calculation device 21 that obtains shape data from the light amount data.
[0082]
In particular, according to the present embodiment, since the width of the separation region Wi is different for each separation region Wi, the partial region WI adjacent to the separation region Wi can be determined with a simple configuration. For example, if the amount of light in the separation region Wi is set to zero, a black stripe-shaped light shielding mask having a different light shielding width for each stripe may be placed on the light emission side of the illumination device 1.
[0083]
The width of the separation area Wi observed from the light receiving means D depends on the three-dimensional shape of the measurement object 10 in the measurement area A, so that the width of the separation area Wi is not observed by the light receiving means D according to the width of the separation area Wi. Absent. This problem can be avoided if the width change for each separation region Wi in the present embodiment is made larger than the width change resulting from the change in the undulation of the three-dimensional shape with respect to the baseline direction.
[0084]
A third embodiment of the present invention will be described with reference to FIG. In the present embodiment, the basic configuration is the same as in the second embodiment, but the light pattern is changed (the design of the filter 7 is changed), and the light pattern in the separation region Wi has a light amount for each separation region Wi. Different light stripes are included.
[0085]
That is, an optical stripe is provided in the separation region Wi, and a plurality of separation regions Wi are specified from the absolute value of the light amount of the light stripe. For example, an optical pattern is prepared in which the isolation region Wi is shielded from light and an optical stripe is arranged in the center of the isolation region Wi. The absolute value of the light stripe is changed for each separation region Wi. If the distribution of the light amount Ri obtained by the light receiving means D is scanned in the baseline direction, the portion where the light amount becomes zero is the separation region Wi, and the portion where the light amount locally increases inside it specifies the separation region Wi. For light stripes. Since this light quantity is known from the light quantity Ri, it is possible to specify the separation regions Wi on both sides of the light stripe. Even if the separation region Wi is brightened over the entire surface and the amount of light is reduced only in the light stripe portion, the light stripe can be similarly identified. Unlike the case of the second embodiment, since the isolation region Wi is specified only by the optical stripe, the width of the isolation region Wi can be minimized.
[0086]
The amount of light reflected by the light stripe changes depending on the reflectance of the measurement object 10, but a larger change than the change of the reflectance of the measurement object 10 may be set to the light amount value of the light stripe in the separation region Wi.
[0087]
FIG. 7 shows an example of transmittance distribution characteristics of the filter 7 of the present embodiment. The light pattern a shown in FIG. 7A is provided with light stripes having different amounts of light for each separation region Wi, and the light amount data received by the CCD 3 is scanned in the baseline direction, thereby allowing the light having different separation regions Wi and light amounts. Since the stripe can be detected, the separation regions W1, W2, and W3 and the corresponding partial regions AI, A2, A3, and A4 can be specified from the difference in the amount of light received by the light stripe, and an unambiguous shape can be calculated. Since the separation region Wi is determined based on the light amount of the light stripe, the light pattern b may not include the light stripe as shown in FIG.
[0088]
A fourth embodiment of the present invention will be described with reference to FIG. In the present embodiment, there are two types of light patterns Pi that illuminate the measurement area A, and the light quantity ratios of the light stripes inside the separation areas Wi of the two light patterns Pi are made different for each separation area Wi. Is.
[0089]
That is, when there are two or more light patterns Pi to be irradiated (this condition is always satisfied in the intensity ratio method), the position of the light stripe is the same for the two light patterns, but the intensity ratio of the two light stripes Is changed for each separation region Wi. Since the intensity ratio does not depend on the reflectance of the measurement object 10, the influence of the reflectance of the measurement object 10 can be removed, and shape measurement independent of the reflectance of the measurement object 10 can be performed.
[0090]
In other words, the separation region Wi is specified in the same manner as in the third embodiment, except that the region determination is performed based on the intensity ratio obtained from the two light stripes rather than the absolute value of the light amount of the light stripe.
[0091]
FIG. 8 shows an example of the transmittance distribution characteristic of the filter 7 of the present embodiment. In the present embodiment, the light patterns a and b shown in FIGS. 8A and 8B are provided with light stripes having different light quantity ratios for each separation region Wi at the same irradiation angle. Since the separation area Wi and the light stripe can be detected by scanning the light quantity data received by the CCD 3 in the baseline direction, the separation areas WI, W2, W3 and the corresponding parts are determined from the intensity ratio of the received light quantity of the two light stripes. Regions AI, A2, A3, and A4 can be specified, and an unambiguous shape can be calculated.
[0092]
A fifth embodiment of the present invention will be described with reference to FIG. In the present embodiment, the amount of light for each wavelength of the light stripe inside the separation region Wi is different for each separation region Wi.
[0093]
That is, the configuration is similar to that of the fourth embodiment except that the intensity ratio of two lights having different wavelengths is used instead of a simple intensity ratio of two light stripes. For example, a light stripe is used in which the mixing ratio of red and blue is changed for each separation region Wi and the color is sequentially changed from blue to red from the left end to the right end in the baseline direction. By using information of a plurality of wavelengths, the condition that there are a plurality of light patterns as in the case of the fourth embodiment becomes unnecessary.
[0094]
When the measurement object 10 is colored, if the reflectance at a certain wavelength is lower than the other wavelengths, the light used in the present embodiment may be set to a wavelength that is not low in reflectance.
[0095]
FIG. 9 shows an example of the transmittance distribution characteristic of the filter 7 of the present embodiment. In the present embodiment, the light patterns a and b shown in FIGS. 9A and 9B are provided with light stripes having different wavelengths for each separation region Wi at the same irradiation angle. In the light pattern a, light stripes are arranged in the order of the separation regions W1, W2, and W3 in the order of red, green, and blue, and in the light pattern b, green and blue. , Red (red). The reason why the wavelengths of the light stripes are different between the two light patterns a and b is that if the reflectance of a specific wavelength is low in the measurement object 10, the light quantity is detected by either of the light stripes. By scanning the light amount data received by the CCD 3 in the base line direction, the separation area Wi and the light stripe can be detected, so that the separation areas W1, W2, W3 and the corresponding partial areas are determined from the intensity ratio of the paired light stripes. A1, A2, A3, and A4 can be specified, and an unambiguous shape can be calculated.
[0096]
A sixth embodiment of the present invention will be described with reference to FIG. In the present embodiment, the light pattern in the separation region Wi includes a plurality of light stripes encoded for each separation region Wi.
[0097]
In other words, the configuration example is similar to that of the third embodiment, except that there are a plurality of optical stripes instead of one, and the separation region Wi is encoded using the number of optical stripes, the interval, and the like. Encoding by the number of light stripes can reliably determine the separation region Wi as long as the light stripe is observed by the light receiving means D. However, when the number of separation regions Wi is large, the number of light stripes arranged in the separation region Wi is Increase. In that case, the number of light stripes can be reduced by changing the interval between the light stripes.
[0098]
However, as in the case of the second embodiment, the interval between the light stripes observed by the light receiving means D depends on the three-dimensional shape of the measurement object 10, and therefore the interval between the light stripes is the shape of the measurement object 10. A width larger than the fluctuation of the optical stripe width resulting from the change is given. Furthermore, as in the fourth and fifth embodiments, the intensity ratio of two optical stripes may be used, or encoding may be performed using optical stripes having different colors.
[0099]
FIG. 10 shows an example of the transmittance distribution characteristic of the filter 7 of the present embodiment. In the present embodiment, the light patterns a and b shown in FIGS. 10A and 10B are provided with different numbers of light stripes for each separation region Wi. For example, in the isolation region W1, the optical patterns a and b are each provided with 1 and 0 optical stripes, the isolation region W2 is 0 and 1 respectively, and the isolation region W3 is 1 and 1 respectively. Since the separation area Wi and the light stripe can be detected by scanning the light amount data received by the CCD 3 in the base line direction, the separation areas W1, W2, W3 and the corresponding partial area A1 are determined from the number of light stripes of the two light patterns. , A2, A3, A4 can be specified, and an unambiguous shape can be calculated.
[0100]
A seventh embodiment of the present invention will be described with reference to FIG. In the present embodiment, the light pattern in the separation region Wi is configured to have a constant light amount distribution in which the light amount is different for each separation region Wi.
[0101]
That is, the configuration is similar to that of the second embodiment, but in the second embodiment, the separation area Wi is specified by the width of the separation area Wi, while the separation area Wi is irradiated with a constant light amount. However, the difference is that the amount of light differs for each separation region Wi. The separation area Wi can be specified from the change in the absolute value of the light amount Ri of the separation area Wi. Since it is not necessary to provide an optical stripe in the isolation region Wi, there is an advantage that the width of the isolation region Wi can be reduced.
[0102]
In this case, as in the case of the third embodiment, the amount of reflected light in the separation area Wi changes depending on the reflectance of the measurement object 10, but a change larger than the change in the reflectance of the measurement object 10 is changed. The light quantity value may be set to.
[0103]
Furthermore, in the present embodiment, a constant light amount ratio is different for each separation region Wi in the separation region Wi of the two light patterns Pi. That is, the intensity of the separation region Wi is changed by two light patterns, and the intensity ratio is different for each separation region Wi. Since the intensity ratio does not depend on the reflectance of the measurement object 10, the influence of the reflectance of the measurement object 10 can be removed, and shape measurement independent of the reflectance of the measurement object 10 can be performed.
[0104]
FIG. 11 shows an example of transmittance distribution characteristics of the filter 7 of the present embodiment. In the present embodiment, the light patterns a and b shown in FIGS. 11A and 11B are set so that the intensity ratios are different when the ratio of the light amounts is taken for each partial area Ai. Since the separation areas W1, W2, and W3 can be detected by scanning the light amount data received by the CCD 3 in the baseline direction, the separation areas W1, W2, and W3 can be detected from the intensity ratios of the separation areas W1, W2, and W3 of the light patterns a and b. W2, W3 and the corresponding partial areas A1, A2, A3, A4 can be specified, and an unambiguous shape can be calculated.
[0105]
An eighth embodiment of the present invention will be described with reference to FIG. In the present embodiment, the constant light amount ratio for each wavelength in the separation region Wi is different for each separation region Wi.
[0106]
That is, the configuration is the same as in the seventh embodiment, but the difference is that the intensity ratio of two lights having different wavelengths is used instead of comparing them with a simple intensity ratio of two light stripes. For example, as in the case of the fourth embodiment, the mixing ratio of red and blue is changed for each separation region Wi, and a light pattern that sequentially changes from blue to red from the left end to the right end in the baseline direction is used for the separation region Wi. By using information of a plurality of wavelengths, the condition that a plurality of light patterns are necessary is eliminated.
[0107]
Similarly to the case of the fourth embodiment, when the measurement object 10 is colored, if the reflectance of a certain wavelength is lower than the other wavelengths, the light used in this embodiment is reflected in the reflectance. What is necessary is just to set to the wavelength which is not low.
[0108]
FIG. 12 shows an example of the transmittance distribution characteristic of the filter 7 of the present embodiment. In the present embodiment, the light patterns a and b shown in FIGS. 12A and 12B have different wavelengths to be irradiated for each partial region Ai. In the light pattern a, the wavelengths are red, green, and blue in the order of the separation regions W1, W2, and W3, and in the light pattern b, green, blue, and red (red). ) In order. By scanning the light amount data received by the CCD 3 in the baseline direction, the separation regions W1, W2, and W3 can be detected, so that the separation regions W1, W2, and W3 can be detected from the wavelengths of the separation regions W1, W2, and W3 of the light patterns a and b. W3 and the corresponding partial areas A1, A2, A3, A4 can be specified, and an unambiguous shape can be calculated.
[0109]
A ninth embodiment of the present invention will be described with reference to FIG. In this embodiment, a shape correction function is provided by providing the document scanner 32 with the shape measuring device 31 according to any one of the embodiments described above.
[0110]
For example, the document scanner 32 schematically illuminates the original reading surface 34a of the original 34 mounted on the flat bed 33 with an illuminating device 35 from above and captures an image based on the reflected light with the imaging device 36. Thus, the original image is read.
[0111]
Here, since the depth of the document 34 viewed from the image pickup device 36 is changed around the binding 34b of a page of a book document such as a dictionary or a telephone book where the document 34 is thick, the shape of the document 34 is changed. It is necessary to read and correct the defocus. Normally, a three-dimensional shape is estimated from a two-dimensional image without depth information under an appropriate assumption. As in the present embodiment, the shape measuring device 31 according to each of the above-described embodiments is also used for shape correction. As a result, depth data can be obtained precisely and defocus correction can be performed accurately.
[0112]
Even if there is no defocusing, it is necessary to correct the shape even when the document 34 is placed obliquely in the depth direction. For example, when a rectangular paper is placed obliquely in the optical axis direction of the image pickup device 36, the closer side looks long and the far side looks like a trapezoid. Since the imaging device 36 itself does not have the distance information of the document 34, it cannot be determined whether the document is a trapezoidal document or a document whose rectangle is inclined in the optical axis direction. As in the present embodiment, by using the shape measuring device 31 according to each of the above-described embodiments in combination, the depth information of the document 34 is obtained from the solid shape information of the document 34, and the image is read into the original rectangle. Data can be corrected.
[0113]
In particular, since the optical shape measuring device 31 using the region division intensity ratio method in which the separation between the partial regions is improved by providing the separation region, the certainty of the measured shape is increased. As a result, a three-dimensional original can be corrected more reliably.
[0114]
Referring to FIG. 13, first, the illumination device 35 irradiates the illumination data of two types of light stripe patterns given from the shape calculation device 37 toward the document 34, and the imaging device 36 applies to each pattern. (Here, the illuminating device 35 is also used as the illuminating means L, and the imaging device 36 is also used as the light receiving means D). The shape information 34 is calculated, and the shape data is sent to the document shape correcting device 38. Next, the image pickup device 36 reads a three-dimensional image of the document 34 and sends the image data of the document 34 to the document shape correction device 38. The original shape correcting device 38 corrects the image data of the three-dimensional original 34 to flat image data based on the uneven shape data, and outputs the corrected original data to a personal computer, a printer, a storage device, or the like.
[0115]
In the present embodiment, the image of the original 34 having only two-dimensional information is compared with the three-dimensional comparison of the original image data corrected by estimating the three-dimensional shape from the deformation of the image. It is possible to correct the shape of a three-dimensional original correctly from an error-free three-dimensional shape obtained by actually measuring information.
[0116]
A tenth embodiment of the present invention will be described with reference to FIGS. In the present embodiment, the projector 52 is provided with the shape measuring device 51 according to any one of the above-described embodiments, so that the tilt correction function of the projection screen 53 is provided.
[0117]
In general, the projector 52 is connected to a personal computer (PC) 55 or the like on the projection screen 53 supported by the support legs 54 or the like, and projects projection light according to image information from the projection device 56. Thus, an image is projected and displayed.
[0118]
Here, when the projection screen 53 is arranged obliquely with respect to the optical axis of the projector 52, for example, as shown in FIG. 15, the image that should have been projected in a rectangular shape is transformed into a trapezoid due to the difference in distance. End up. In this regard, if the depth of the projection screen 53 is measured using the shape measuring device 51 as in this embodiment, an imaging device 57 such as a normal camera is provided on the projector 52 side (as the illumination means L). For example, the projection device 56 can be used), and the tilt correction can be performed with higher accuracy than the determination of the tilt of the projection screen 53 from the deformation of the shape.
[0119]
In particular, as described above, since the optical shape measuring device 51 using the area division intensity ratio method in which the separation between the partial areas is improved by providing the separation area, the certainty of the measured shape is increased. As a result, the tilt correction of the projection screen 53 can be more reliably performed.
[0120]
Referring to FIG. 15, the projection device 56 in the projector 52 irradiates the projection screen 53 with illumination data of two types of light stripe patterns given from the shape calculation device 58 and images each of the light patterns. The image data is fetched from the device 57 to the shape calculation device 58, the shape information of the projection screen 53 is calculated based on the principle of the striped intensity ratio method, and the obtained shape data is sent to the projection correction device 59. Next, the image data sent from the PC 55 is sent to the projection correction device 59, and irradiated onto the projection screen 53 by the projection device 56 as corrected image data obtained by correcting the tilt of the projection screen 53 obtained from the shape data.
[0121]
Thus, according to the projector 52 of the present embodiment, the projection image is corrected by measuring the shape of the tilt of the projection screen 53, and the projection screen 53 is inclined with respect to the projector 52 as shown in FIG. Even if it is arranged, the projected screen can be projected as a rectangle without being transformed into a trapezoid. Further, since the actual shape of the projection screen 53 is measured, the deformation on the projection screen 53 can be corrected not only when the projection screen 53 is simply tilted but also when it is wavy. .
[0122]
【The invention's effect】
According to the first aspect of the present invention, by providing the separation regions Wi between the partial regions Ai of the region division method, the partial regions Ai can be clearly separated from each other, and the shape abnormality that occurs at the boundary of the partial regions Ai Since the value can be removed, there is no possibility of giving an incorrect shape because the boundary of the partial area Ai disappears.
[0123]
According to the second aspect of the present invention, the separation region Wi is provided between the partial regions Ai of the region division method, and at the same time, the adjacent partial region Ai is specified from the information of the optical pattern of the separation region Wi, thereby the region division method. Since the determination of the partial area Ai can be simplified, the shape can be measured easily with high accuracy.
[0124]
According to the invention described in claim 3, in the shape measuring apparatus according to claim 2, since the width of the separation region Wi is changed for each separation region Wi, the partial region Ai adjacent to the separation region Wi is easily determined. be able to.
[0125]
According to a fourth aspect of the invention, in the shape measuring apparatus according to the second aspect, since the light pattern in the separation region Wi includes the light stripes having different light amounts for each separation region Wi, it is easily adjacent to the separation region Wi. The partial area Ai can be determined.
[0126]
According to the fifth aspect of the invention, in the shape measuring apparatus according to the fourth aspect, there are two types of patterns Pi, and the light quantity ratio of the light stripes in the separation area Wi is different for each separation area Wi. The partial area Ai adjacent to Wi can be determined.
[0127]
According to the sixth aspect of the present invention, in the shape measuring apparatus according to the second aspect, the amount of light for each wavelength of the light stripe inside the separation region Wi is different for each separation region Wi. The area Ai can be determined.
[0128]
According to the seventh aspect of the present invention, in the shape measuring apparatus according to the second aspect, since the optical pattern including the optical stripe encoded for each separation region Wi is used, the portion adjacent to the separation region Wi is easily provided. The area Ai can be determined.
[0129]
According to the eighth aspect of the invention, in the shape measuring apparatus according to the second aspect, since a constant light pattern having a different amount of light is used for each separation region Wi, the partial region Ai adjacent to the separation region Wi can be easily obtained. Can be determined.
[0130]
According to the ninth aspect of the invention, in the shape measuring apparatus according to the eighth aspect, since the constant light pattern having a different light quantity ratio is used for each separation region Wi, the partial region Ai adjacent to the separation region Wi can be easily used. Can be determined.
[0131]
According to the tenth aspect of the present invention, in the shape measuring apparatus according to the eighth aspect, since the constant light pattern in which the light amount ratio for each wavelength is different for each separation region Wi is used, it is adjacent to the separation region Wi easily. The partial area Ai can be determined.
[0132]
According to the document scanner of the eleventh aspect of the present invention, since the shape measuring apparatus according to any one of the first to tenth aspects of the present invention is provided with a high measurement accuracy and a simple configuration, a document having irregularities such as a book shape can be obtained. The shape of the document scanner to be read can be corrected simply and reliably.
[0133]
According to the projector of the twelfth aspect of the present invention, since the shape measuring device according to any one of the first to tenth aspects having a high measurement accuracy and a simple configuration is provided, the tilt of the projection screen of the projector is corrected, Correction that can be projected onto a rectangle even on an obliquely arranged screen can be easily performed.
[Brief description of the drawings]
FIG. 1 is a principle perspective view showing a shape measuring apparatus according to a first embodiment of the present invention.
FIG. 2 is a schematic plan view showing a more practical configuration example.
FIG. 3 is a schematic perspective view showing a filter.
FIG. 4 is a transmittance distribution characteristic diagram of a filter showing a configuration example of an optical pattern.
FIG. 5 is a schematic plan view showing a configuration example of a shape measuring apparatus according to a second embodiment of the present invention.
FIG. 6 is a characteristic diagram showing a configuration example of an optical pattern.
FIG. 7 is a transmittance distribution characteristic diagram of a filter showing a configuration example of an optical pattern according to a third embodiment of the present invention.
FIG. 8 is a transmittance distribution characteristic diagram of a filter showing a configuration example of an optical pattern according to a fourth embodiment of the present invention.
FIG. 9 is a transmittance distribution characteristic diagram of a filter showing a configuration example of an optical pattern according to a fifth embodiment of the present invention.
FIG. 10 is a transmittance distribution characteristic diagram of a filter showing a configuration example of an optical pattern according to a sixth embodiment of the present invention.
FIG. 11 is a transmittance distribution characteristic diagram of a filter showing a configuration example of an optical pattern according to a seventh embodiment of the present invention.
FIG. 12 is a transmittance distribution characteristic diagram of a filter showing a configuration example of an optical pattern according to an eighth embodiment of the present invention.
FIG. 13 is a schematic perspective view illustrating a configuration example of a document scanner according to a ninth embodiment of the present invention.
FIG. 14 is a schematic plan view showing a configuration example of a projector according to a tenth embodiment of the invention.
FIG. 15 is a schematic perspective view thereof.
FIG. 16 is a perspective view for explaining an optical cutting method.
FIG. 17 is a schematic plan view for explaining the principle of triangulation.
FIG. 18 is a schematic plan view for explaining a rainbow method.
FIG. 19 is a perspective view for explaining an intensity ratio method.
FIG. 20 is a schematic plan view for explaining a region division intensity ratio method.
FIG. 21 is a transmittance distribution characteristic diagram of a filter showing a configuration example of an optical pattern.
[Explanation of symbols]
L Illumination means
D Light receiving means
A Measurement area
Ai partial area
Wi separation area
1 Illumination means
2 Light receiving means
4 Shape estimation means
5 Shape correction means
21 Shape calculation means
31 Shape measuring device
34 Document Manuscript
51 Shape measuring device
53 Projection screen

Claims (12)

Partial region numbers consisting of n slit-shaped partial regions Ai (i: 1 to n) that are divided perpendicularly to the parallax direction and do not overlap each other with the separation region Wi (i = 1 to n−1) therebetween. Illuminating means for illuminating two or more light patterns Pi for each paired region of the partial region Ai and the separation region Wi with respect to the measurement region A consisting of
A light receiving means for receiving the reflected light of the light pattern Pi with the parallax for the illumination means specified in advance and illuminated on the measurement area A;
Based on the information on the light amount Ri of the reflected light received by the light receiving means, the partial area Ai is used by using the parallax between the illumination means and the light receiving means while leaving the ambiguity of the partial area number i regarding the partial area Ai. Shape estimation means for estimating the shape data Si of
Based on the information on the light amount Ri of the reflected light, the position of each separation area Wi is specified, the position of the partial area Ai adjacent to the specified separation area Wi is specified, and the estimation is performed for each partial area Ai. A shape measuring device comprising: shape correcting means for removing the ambiguity of the partial area number i in the obtained shape data Si and obtaining the unambiguous shape data Zi of the partial area number i for each partial area Ai. Partial region numbers consisting of n slit-shaped partial regions Ai (i: 1 to n) that are divided perpendicularly to the parallax direction and do not overlap each other with the separation region Wi (i = 1 to n−1) therebetween. Illuminating means for illuminating two or more light patterns Pi for each paired region of the partial region Ai and the separation region Wi with respect to the measurement region A consisting of
A light receiving means for receiving the reflected light of the light pattern Pi with the parallax for the illumination means specified in advance and illuminated on the measurement area A;
Among the information of the light quantity Ri of the reflected light received by the light receiving means, the corresponding partial area Ai is specified using the information of the light quantity Ri of the reflected light from the separation area Wi, and the illumination means and the light receiving means A shape measuring device comprising: shape calculating means for obtaining shape data Zi for each partial area Ai based on the principle of triangulation using the parallax.   The shape measuring apparatus according to claim 2, wherein the widths of the separation regions Wi are different from each other.   The shape measuring apparatus according to claim 2, wherein the light pattern in the separation region Wi includes a light stripe having a different amount of light for each separation region Wi.   5. The shape measuring apparatus according to claim 4, wherein there are two types of the light patterns Pi, and the light quantity ratio of the light stripe in the separation region Wi is set to be different for each separation region Wi between the two types of light patterns Pi.   The shape measuring apparatus according to claim 2, wherein the amount of light for each wavelength of the light stripe in the separation region Wi is different for each separation region Wi.   The shape measuring apparatus according to claim 2, wherein the light pattern in the separation region Wi includes a light stripe encoded for each separation region Wi.   The shape measuring apparatus according to claim 2, wherein the light pattern in the separation region Wi is a pattern having a constant light amount distribution in which the light amount is different for each separation region Wi.   9. The shape measuring apparatus according to claim 8, wherein there are two types of the light patterns Pi, and a constant light amount ratio is set to be different for each separation region Wi in the separation regions Wi of the two types of light patterns Pi.   The shape measuring apparatus according to claim 8, wherein a constant light amount ratio for each wavelength in the separation region Wi is different for each separation region Wi.   A document scanner comprising the shape measuring apparatus according to claim 1, wherein a measurement region is set with a document original as a measurement object.   A projector comprising the shape measuring device according to claim 1, wherein a measurement area is set using a projection screen as a measurement object.

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