JP2021089264A - Marker - Google Patents

Abstract

To provide a new marker enabling the use of an existing marker mounted unit and capable of narrowing a target detection angle.SOLUTION: A marker 1 includes a lens body 10. The lens body 10 has a plurality of lens portions 11 on one surface side, and has a plurality of detected portions 12 on the other surface side. The plurality of lens portions 11 are continuously disposed in a primary dimensional direction at fixed pitches on the one surface side, and the plurality of detected portions 12 are disposed at intervals in the primary dimensional direction at fixed pitches on the other surface side. The pitch of the plurality of lens portions 11 and the pitch of the plurality of detected portions 12 are different from each other. Each lens portion 11 corresponds to each detected portion 12, and the center of the detected portion 12 is disposed in a region of 1/2 of the length of the lens portion 11 around a center axis C of the lens portion 11 in the primary dimensional direction.SELECTED DRAWING: Figure 1

Description

The present invention relates to markers.

In fields such as Augmented Reality (hereinafter, also referred to as “AR”) and robotics, so-called visual markers are used to recognize the position and orientation of an object. As the visual recognition marker, for example, a two-dimensional visual recognition marker such as an AR marker is generally used. In order to accurately detect the AR marker attached to an object, it is required to accurately detect the angle and distance of the AR marker. Therefore, it has become common to use a detection reference unit for reference for determining an angle and a distance, a variable moiré pattern (VMP) marker, and a two-dimensional marker as a marker mounting unit mounted on one substrate. There is. The detection reference unit has, for example, circular marks provided at the four corners of the substrate. Further, the VMP marker is a marker whose image changes according to a viewing angle. The VMP marker is, for example, a marker in which a lenticular lens is arranged on a black striped pattern (Patent Document 1), and when a detection device such as a camera detects a linear image appearing on the VMP marker, the VMP marker is described. The linear image moves in the direction perpendicular to the line, depending on the viewing angle of the camera with respect to the marker. Therefore, the marker mounting unit is obtained by roughly measuring the angle and distance from the change in the shape of the circular mark of the detection reference portion, and further detecting the movement of the image of the VMP marker (change in the moire pattern). You can accurately judge the rotation angle and distance of.

The range of the rotation angle detected by the VMP marker has generally been about ± 24 °. However, in recent years, there has been a demand for accurate detection at angles in a narrower range.

Japanese Unexamined Patent Publication No. 2012-145559

The range of the rotation angle of the VMP marker can be designed by changing, for example, the overall size of the marker, the shape of the lens, and the like. However, the VMP marker is usually used as a marker mounting unit having a plurality of functions required for a substrate. Specifically, a substrate on which a through hole for a VMP marker is formed in advance is used, the VMP marker is inserted into the through hole, and the detection reference unit, a two-dimensional visual recognition marker, and the like are also mounted on the substrate. By doing so, a marker mounting unit is manufactured. Therefore, in terms of manufacturing, it is required to use an existing substrate used in an existing marker mounting unit. As described above, the VMP marker can change the range of rotation angles to be detected. However, the present inventor has no choice but to change the size of the VMP marker itself when changing the range of the rotation angle to be detected, based on the common general knowledge at the time of filing, and the existing substrate cannot be used. On the other hand, it has been found that if the marker is limited to a size corresponding to the existing substrate, a problem such that an image is detected even at an angle outside the target angle range occurs.

Therefore, an object of the present invention is to provide a new marker that enables the use of an existing marker mounting unit and can narrow the range of a target detection angle.

To achieve the above object, the markers of the present invention include a lens body.
The lens body has a plurality of lens portions on one surface side and a plurality of detected portions on the other surface side.
The plurality of lens portions are continuously arranged in the one-dimensional direction at a constant pitch on one surface side thereof.
The plurality of detected portions are arranged on the other surface side at a constant pitch at intervals in the same one-dimensional direction.
The pitches of the plurality of lens portions and the pitches of the plurality of detected portions are different.
Each of the lens portions corresponds to each of the detected portions, and corresponds to each of the detected portions.
In the one-dimensional direction, the center of the detected portion is arranged in a region having a length of ½ of the lens portion, centered on the central axis of the lens portion.

As described above, the marker of the present invention makes it possible to use an existing marker mounting unit by keeping the position of the center of the detected portion within a predetermined range of the lens portion in the entire marker. , The range of the target detection angle can be narrowed. Specifically, for example, it is possible to avoid an increase in the thickness of the lens portion and narrow the range of the detection angle while maintaining the size of the marker assumed in the existing marker mounting unit. Therefore, according to the marker of the present invention, for example, the variation of the detection angle range can be easily set, and the productivity of the marker and the marker mounting unit can be improved.

FIG. 1 is a schematic view showing an example of the markers of the first embodiment. It is a figure. FIG. 2 is a cross-sectional view showing an example of one lens unit including a lens portion and a detected portion in the marker of the first embodiment. 3A and 3B are cross-sectional views showing an example of a conventional VMP marker, respectively. FIG. 4 is a partial cross-sectional view of the marker of the first embodiment and the conventional marker. FIG. 5 is a partial cross-sectional view of the marker of the first embodiment and the conventional marker. FIG. 6 is a schematic view showing the movement of the image projected on the lens portion in the marker of the first embodiment. FIG. 7 is a schematic view illustrating an angle of an optical axis in which an image is generated at the same viewing angle in the marker of the first embodiment and the conventional marker. In FIG. 8, (A) is a schematic view of a conventional marker-mounted unit, and (B) is a schematic view of a marker-mounted unit of the second embodiment. 9A and 9B are schematic views of a pair of markers in a conventional marker-mounted unit, and FIG. 9B is a schematic diagram of a pair of markers in the marker-mounted unit of the second embodiment.

An embodiment of the present invention will be described with reference to the drawings. The present invention is not limited or limited by the following embodiments. In each figure, the same parts are designated by the same reference numerals. In each figure, the Z-axis direction is the vertical direction, and the upward direction is the visual viewing side. The X-axis direction is a one-dimensional direction (longitudinal direction) in which the lens portion is continuous. The X-axis direction is also referred to as a rotation direction. The rotation direction is, for example, a direction of rotational movement with respect to the viewing side, and a movement direction of an image appearing on the surface of the lens body 10. The Y-axis direction is a direction orthogonal to the X-axis direction (short direction). In the present embodiment, for convenience, the longitudinal direction and the lateral direction are described, but the directions may be intersecting and are not limited to the actual length.

[Embodiment 1]
FIG. 1 shows an example of the markers of the present embodiment. FIG. 1 is a schematic view showing an example of the marker 1 of the present embodiment. The right side is a top view, a sectional view in the I-I direction, and a bottom view from the top, and the left side is in the Y-axis direction (short direction). It is a side view.

The marker 1 has a lens body 10, and the lens body 10 has a plurality of lens portions 11 on one surface side (upper surface side) and a plurality of lens portions 11 on the other surface side (lower surface side). It has a detected portion 12 of the above. When the marker 1 is used, the detected portion 12 is projected as an image moving in the X-axis direction on the upper surface side of the lens body 10, and can be optically detected. Specifically, for example, the marker 1 is generally converted into image data by detecting an image with light in a visible light region (for example, 400 nm to 700 nm) and photographing the image with a camera. In the present invention, the light for detecting the marker 1 is not limited to the light in the visible light region, and is, for example, an ultraviolet light region (for example, 250 nm to 400 nm) or an infrared light region (for example, 700 nm to 4,000 nm). The image may be detected and photographed by the light of the above, and converted into image data. When the image is detected by light other than the visible light region, for example, it is not necessary to change the configuration of the marker 1, and a camera or a filter matching the wavelength of the light may be used. Further, by using light other than the visible light region, for example, noise caused by lighting during work can be reduced, so that the image can be captured more clearly, and further, lighting during work can be performed. The range of condition selection can be expanded.

Marker 1 is, for example, a variable moire pattern (VMP) marker. Hereinafter, a VMP marker will be given as a specific example of the marker 1, but the present invention is not limited thereto.

In the lens body 10, for example, as shown in FIG. 1, a plurality of lens portions 11 are continuously arranged on the upper surface side in a one-dimensional direction (X-axis direction) and a direction intersecting the one-dimensional direction (Y-axis direction). It has a lens array structure. The intersections may be, for example, orthogonal, non-parallel and non-orthogonal. Further, the lens body 10 is not limited to the lens array structure. For example, the lens portion 11 has a cylindrical structure, and a plurality of lens portions 11 are continuously arranged in a one-dimensional direction (X-axis direction). It may have a lenticular lens structure. A plurality of lens unit 11 in the X-axis direction, are arranged at a constant pitch (P _L). In the present invention, the "lens unit pitch" means the pitch between adjacent lens units 11 in the one-dimensional direction (X-axis direction), and is, for example, the distance between the central axes of the lens units 11. Further, the "pitch of the lens unit" can be said to be the width of the lens unit 11 when the length of each lens unit 11 in the X-axis direction is constant, for example, as shown in FIG. The central axis of the lens unit 11 is an axis in the vertical direction that passes through the apex of the lens unit.

The plurality of detected portions 12 are arranged on the lower surface side at intervals in the same X-axis direction as the lens portion 11. A plurality of the detecting section 12 in the X-axis direction, are arranged at a constant pitch (P _D). In the present invention, the "pitch of the detected portion" means the pitch between adjacent detected portions 12 in the one-dimensional direction (X-axis direction), for example, the distance between the central axes of the detected portions 12. Is. As shown in FIG. 1, for example, the detected portion 12 is a line extending in the Y-axis direction, and a plurality of detected portions 12 form a solid line striped pattern parallel to the Y-axis direction. Further, the detected unit 12 is not limited to this example, and is, for example, a dot line in which a plurality of dots are connected at intervals in the Y-axis direction, and is parallel to the Y-axis direction by the plurality of detected units 12. A striped pattern of dot lines may be formed.

Each lens portion 11 on the upper surface side corresponds to each detected portion 12 on the lower surface side (also referred to as “pair”). In the lens body 10 of FIG. 1, for example, one row of lens units 11 extending in the Y-axis direction corresponds to a single detected unit 12 extending in the Y-axis direction. In the lens body 10, a pitch of the plurality of lenses 11 and _{(P L),} the pitch of the plurality of detected portions 12 _{(P D)} is different. In Figure 1, the relationship between the pitch _{(P L)} and the detected portion 12 pitch _{(P D)} of the lens unit 11 is a PL> PD, this is not limited, for example, may be PL> PD However, PL <PD may be used.

The positional relationship of the detected unit 12 with respect to the corresponding lens unit 11 is as follows. That is, for the total length of the lens unit 11 in the X-axis direction _{(L L),} in the region of the length of 1/2 about the central axis C of the lens unit 11 _{(L L} / 2), the detection unit Twelve centers are arranged. FIG. 2 shows a cross-sectional view of the lens body 10 in the cross-sectional view taken in the I-I direction of FIG. 1 in which one unit including the lens portion 11 and the detected portion 12 is extracted. As shown in FIG. 2, when the total length of the lens portion 11 in the X-axis direction is _LL , it is within the region of _{1/2 length (LL} / 2) centered on the central axis C of the lens portion 11. , The center of each detected portion 12 is arranged. Specifically, in FIG. 2, in the combination of the lens unit 11 and the detected unit 12 included in the marker 1, the centers of all the detected units 12 are arranged in the region. The length of the region is _LL / 2, preferably _LL / 3. Further, as described above, the center of the detected portion 12 may be within the region, and for example, it is more preferable that the detected portion 12 is arranged within the region.

The size of the lens body 10 and each part is not particularly limited, and can be appropriately determined depending on, for example, the number of lens parts 11, the use of the marker 1, and the like.

Lens unit 11, the length of the X-axis direction _{(L L)} is, for example, a 5 to 150 mm, the length in the Y-axis direction, for example, 1 to 30 mm. The thickness of the lens portion 11 is, for example, the thickness of the central axis, which is 0.2 to 10 mm. In the lens body 10, the number of lens units 11 is not particularly limited, and the number in the X-axis direction is, for example, 20 to 250. When the lens body 10 is a lens array, the number of lens units in the Y-axis direction is the number. For example, 19 to 249 pieces, 4 to 50 pieces.

The surface shape of the lens unit 11 is, for example, a shape having a function of collecting light from the surface (condensing function). The shape of the lens portion 11 of the marker 1 shown in FIG. 1 is a spherical shape (also referred to as an R shape), and specifically, is a convex curved surface. The surface shape of the lens portion 11 is, for example, a shape in a cross section in the thickness direction Z along the X axis. It is preferable that all the lens portions 11 included in the lens body 10 have the same surface shape, for example. The curvature of the curved surface of the lens portion 11 is not particularly limited. The curved surface of the lens unit 11 in the X-axis direction has a radius of curvature (R) of, for example, 0.1 to 10 mm. When the lens body 10 is the lens array of FIG. 1, the curved surface of the lens unit 11 in the Y-axis direction may be the same as, for example, the radius of curvature of the curved surface in the X-axis direction, and is preferably the same. ..

The detected portion 12, the length of the X-axis direction _{(L D)} is, for example, a 5 to 1000 m, the length in the Z-axis direction (thickness) is, for example, 1 to 30 [mu] m. The detected portion 12 may be formed, for example, in a state of protruding from the lower surface (exposed surface) of the lens body 10 in the Z-axis direction of the marker 1, or the lower surface (exposed surface) of the lens body 10 has a recess. However, it may be formed in the recess.

In the lens body 10, the size, shape, and the like of the recess can be appropriately set according to, for example, the detected portion 12. The length (depth) of the recess in the Z-axis direction is not particularly limited, and is, for example, 1 to 100 μm.

The length of the detected unit 12 in the X-axis direction can be appropriately determined, for example, according to the pitch between adjacent lens units 11. In the X-axis direction, the ratio between the pitch _{(P L)} between the length of the detector 12 _{(L D),} the lens unit 11, for example, 1: 200 to 1: 5. X-axis direction length of the detector 12 (L _D), relative to the pitch (P _L) between the lens unit 11, by setting relatively large, for example, a relative image contrast to be detected By setting it to be relatively large and relatively small, for example, the sensitivity of the detected unit 12 can be further improved.

The lens body 10 may be formed by separately preparing a lens unit having a lens portion 11 and connecting the lens units, or may be an integrally molded product having the lens portion 11 on the surface. The lens body 10 is, for example, an injection-molded product, and in particular, in the case of the integrally molded product, it is preferably an injection-molded product.

The method of forming the lens portion 11 in the lens body 10, particularly the method of forming the lens surface is not particularly limited, and for example, precision machining (extreme machining), cutting by a machining center or the like, laser machining such as a fiber laser, electric discharge machining, electrochemical machining. Processing, etching processing, photomask processing, etc. can be adopted. Further, the lens portion 11 of the lens body 10 may be further subjected to a wrap treatment, a polishing treatment, a blast treatment, or the like on the surface thereof, for example.

The lens body 10 is, for example, a translucent member. The translucent member is not particularly limited, and examples thereof include resin and glass. Examples of the resin include polycarbonate, acrylic resins such as polymethyl methacrylate (PMMA), cycloolefin polymers (COP), cycloolefin copolymers (COC) and the like.

The detected unit 12 may be optically detected, and examples thereof include a colored film. The color of the coloring film is not particularly limited, and is, for example, black. The colored film is, for example, a coating film and can be formed by a paint. The coating material is not particularly limited, and may be, for example, a liquid coating material or a powder coating material. The coating film can be formed, for example, by applying and / or solidifying. Examples of the coating method include spray coating and screen printing. Examples of the solidification method include drying of the liquid paint, curing of a curing component (for example, a radically polymerizable compound, etc.) in the paint, baking of the powder paint, and the like.

The detected unit 12 may be, for example, optically distinguishable. The optically distinguishable means that, for example, the detected portion 12 can detect with an optically significant difference as compared with the other regions. The optically significant difference means, for example, having a significant difference in optical characteristics. Examples of the optical characteristics include hue such as lightness, saturation, and hue, and light intensity such as brightness. The optically significant difference may be, for example, a difference that can be visually confirmed or a difference that can be confirmed by an optical detection device such as a camera. Further, when the detected unit 12 emits fluorescence, for example, the difference may be identifiable by an operation such as irradiation with a UV lamp.

Next, the effect of the marker of the present invention will be described by comparison with a conventional marker. 3A and 3B show cross-sectional views of the conventional VMP marker in the thickness direction along the X-axis direction. In FIG. 3, the solid line C is the central axis of the lens unit 11, and the dotted line P is the optical path to which the detected unit 12 corresponding to the lens unit 11 is the focal point. When this optical path has a viewing angle, an image of the target portion 12 to be detected appears on the corresponding lens portion 11. That is, when the image is rotated in the X-axis direction, the image moves in the X-axis direction according to the rotation angle (viewing angle).

The conventional VMP marker is configured assuming, for example, detection of rotation of about ± 24 ° in the X-axis direction. Here, as an example of a VMP marker having a detection angle of ± 24 °, a marker 2 in which the lens portion 11 is _{set to have a radius of curvature R = α and a thickness (D 1} ) = β mm of the central axis C is shown in FIG. 3 (A). It is shown in the sectional view. The marker 2 has a detected portion 12 arranged on the central axis of the lens portion 11 at the center in the X-axis direction. Then, as the lens portion 11 is located on the left side, the position of each detected portion 12 moves to the right end portion side of the corresponding lens portion 11, and the detected portion 12 with respect to the lens portion 11 at the left end. Is arranged so as to be the right end portion of the lens portion 11. On the other hand, as the lens portion 11 is located on the right side, the position of each detected portion 12 moves to the left end portion side of the corresponding lens portion 11, and the detected portion 12 with respect to the lens portion 11 at the right end. Is arranged so as to be the left end portion of the lens portion 11. In this way, with respect to the continuous lens unit 11, the detected unit 12 is arranged in the entire region from the central axis to both ends of the lens unit 11, so that the lens from the left end lens unit 11 to the right end lens By moving the image in the entire area up to the part 11, detection of ± 24 ° becomes possible. However, in recent years, it has been required to be able to detect accurately in a narrower range of angles. Specifically, for example, it is required to set the detection angle to ± 10 °, ± 5 °, or the like to improve the angle detection accuracy. As a specific example, when a predetermined angle range is detected using the entire region from the left end lens portion 11 to the right end lens portion 11 using a marker having the same structure, the narrower the detection angle range, the narrower the detection angle range. It is considered that the accuracy of angle detection is improved because the moving ratio of the image with respect to the change of 1 ° increases.

Therefore, it is necessary to design a VMP marker that narrows the range of the detection angle. Further, the VMP marker is inserted into a through hole or the like provided on the substrate, and is used as a marker mounting unit together with a circular detection reference unit and an AR marker mounted on the same substrate. Therefore, when manufacturing a VMP marker with a changed detection angle, in order to utilize the existing marker mounting unit, it is required to maintain the length and width of the VMP marker from the point of insertion into the through hole. Be done. Here, an example of a conventional VMP marker having a narrowed detection angle range is shown in the cross-sectional view of FIG. 3B. The marker 3 has a length in the X-axis direction and a Y-axis direction, the number of the lens unit 11 and the detected unit 12, the pitch of the lens unit 11, and the position of the detected unit 12 with respect to the marker 2 in FIG. 3 (A). And the pitch is the same. Specifically, the position of the detected unit 12 covers the entire area from the right end to the left end of the lens unit 11. Therefore, in order to set the detection angle of the marker 3 to ± 12 °, that is, ± 12 ° is detected by moving the image of the entire region from the lens portion 11 at the left end to the lens portion 11 at the right end. to set, for the lens unit 11, and approximately 2α radius of curvature R, it is necessary to set the thickness of the central axis C of (D ₂₎ roughly 2Betamm. Further, assuming that the detection angle is further narrowed to ± 8 °, it is necessary to set the radius of curvature R of the lens unit 11 to be approximately 3α and the thickness of the central axis C to be approximately 3β mm. In this way, as the range of the detection angle is relatively narrowed, the thickness of the lens portion becomes relatively thick. For example, at ± 12 °, a thickness more than about twice ± 24 ° is required, and ± 8 °. Then, a thickness of more than about 3 times ± 24 ° is required. When the thickness is increased in this way, there is a problem that the VMP marker protrudes from the upper surface of the substrate in the thickness direction even if it can be inserted into the substrate of the existing marker mounting unit.

In addition to the problem of the thickness of the lens portion, there is also a problem that an image is generated even at an angle close to the above range that is not desired to be seen even though the detection angle is out of the target detection angle range. As a specific example, in the case of the marker 3 set to ± 12 °, for example, when the marker 3 is rotated from -12 ° to + 12 °, the image moves from the lens portion at the right end to the lens portion at the left end. (Image of the first lap) If it exceeds + 12 °, the image of the second lap will newly appear in the lens portion at the right end. The same applies to the marker 3 set to ± 8 °, and if it exceeds + 8 °, an image of the second lap is generated. If the detection angle is set to ± 3 °, the same thing will happen, and a new image will appear every 6 ° change. Even if it deviates from the target detection angle range, a new image will appear at the same position at an angle close to it, so even though the image on the second lap is noise, misreading will occur and measurement will occur. It may lead to an error.

On the other hand, the marker of the present invention has a length ( _LL ) in the X-axis direction, the number of the lens unit 11 and the detected unit 12, the pitch of the lens unit 11, and the detected unit, as compared with the conventional marker 2. Even if the pitches of 12 are the same, it is not necessary to increase the thickness in the Z-axis direction as in the marker 2 for the following reasons, and even though the pitch is out of the target detection angle range, the above range It is possible to prevent the problem that an image is generated even at an angle that is close to the image that you do not want to see.

That is, in the marker of the present invention, for example, as shown in the markers 1 of FIGS. 1 and 2 described above, the center of each detected portion 12 corresponding to each lens portion 11 is the central axis of the lens portion 11. As the center, it is contained in a region of 1/2 of _{the length (LL} ) of the lens portion 11 in the X-axis direction. Here, FIGS. 4 and 5 show cross-sectional views of the marker 1 of the present embodiment and the conventional markers 2 and 3 by extracting the leftmost lens portion in the X-axis direction and comparing them, respectively.

In FIG. 4, the upper left is a partial cross-sectional view of the left end of the conventional marker 2, the upper right is a partial cross-sectional view of the left end of the marker 1 of the present embodiment, and the lower left is the cross-sectional view of the conventional marker 2 and the present embodiment. It is the figure which overlapped with the said sectional view of the marker 1. As described above, the conventional marker 2 has a detection angle of ± 24 °, a radius of curvature R = α of the lens unit 11, and a thickness (D ₁ ) β mm of the central axis C, while detecting the marker of the present invention. When the angle is set to ± 12 °, the radius of curvature R of the lens unit 11 can be set to the same α in the marker 1 of the present embodiment. As shown in the upper left figure of FIG. 4, as described above, in the conventional marker 2, the detected portion 12 is arranged over _{the entire region (LL) from the right end to the left end of the lens portion 11.} Therefore, specifically, as shown in the upper left figure of FIG. 4, the detected portion 122 is arranged at a position corresponding to the right end portion of the left end lens portion 11. On the other hand, the marker 1 of the present embodiment has a length _{of 1/2 of the length (LL} ) of the entire region and is detected within the range of the region centered on the central axis C. The center of part 12 is settled. Therefore, specifically, as shown in the upper right figure of FIG. 4, the lens portion 11 at the left end is detected not at the right end but at a position corresponding to the right end of _{LL / 2 from the center.} The unit 121 is arranged. Comparing the two optical paths, as shown in the lower left figure of FIG. 4, the optical path P1 of the marker 1 of the present embodiment has an angle with respect to the central axis (optical path of 0 °) as compared with the optical path P2 of the conventional marker 2. However, it is a narrow range. As a result, the marker 1 of the present embodiment has a range of angles at which the detected portion 12 is the focal point in the entire marker 1 even under the same thickness, the same number of lenses, and the like as compared with the conventional marker 2. Is narrowed, and the generation of an image at an angle that you do not want to see can be suppressed.

Further, the marker 1 of the present embodiment can be set to narrow the range of the detection angle in the entire marker while maintaining the same size (length, width, thickness) as the conventional marker 2, for example. By setting the range of the detection angle detected by the entire marker to be narrow in this way, for example, the image appearing on the lens portion can be greatly moved by a rotation of 1 °. Therefore, the detection sensitivity can be further improved as compared with a marker having a narrow range of movement at 1 ° rotation.

In FIG. 5, the upper left is a partial cross-sectional view of the left end of the conventional marker 3, the upper right is a partial cross-sectional view of the left end of the marker 1 of the present embodiment, and the lower left is the cross-sectional view of the conventional marker 3 and the present embodiment. It is the figure which overlapped with the said sectional view of the marker 1. As described above, the conventional marker 3 has a detection angle of ± 12 °, a radius of curvature R of the lens portion 11 R = 2α, and a thickness (D ₂ ) of the central axis C of 2β mm, while detecting the marker of the present invention. When the angle is set to ± 12 °, in the marker 1 of the present embodiment, the radius of curvature R of the lens unit 11 can be set to the same α, and the thickness (D ₁ ) of the central axis is the same as that of the conventional marker 3. Can be set to β mm. As shown in the upper left figure of FIG. 5, as described above, in the conventional marker 3, the detected portion 123 is arranged over _{the entire region (LL) from the right end to the left end of the lens portion 11.} Therefore, in order to make the detection angle ± 12 °, the thickness (D ₂ ) needs to be 2 β mm, which is twice the thickness of the conventional marker 2. On the other hand, the marker 1 of the present embodiment has a length _{of 1/2 of the length (LL} ) of the entire region and is detected within the range of the region centered on the central axis C. The center of part 12 is settled. Therefore, specifically, as shown in the upper right figure of FIG. 5, the lens portion 11 at the left end is detected not at the right end but at a position corresponding to the right end of _{LL / 2 from the center.} The center of the portion 121 is arranged. Comparing the thicknesses of the two, as shown in the lower left figure of FIG. 5, the thickness (D ₁ ) of the marker 1 of the present embodiment is halved of the thickness (D ₂ ) of the conventional marker 3. There is. As a result, the marker 1 of the present embodiment is set to a detection angle in a narrow range in the entire marker 1 without increasing the thickness as compared with the conventional marker 3, and an image is generated at an angle that is not desired to be seen. It can be suppressed.

Specifically, when the movement of the image between the leftmost lens portion 11 and the rightmost lens portion 11 is set to a detection angle of ± 12 °, the marker 1 of the present embodiment is rotated from -12 ° to + 12 °. Along with that, the image moves from the lens part at the right end to the lens part at the left end (image of the first lap), but when it exceeds + 12 °, a new image of the second lap immediately appears. It never appears. For example, assuming that the lens thickness is β mm, which is the same as that of the conventional marker 2, the image of the second lap does not occur until + 36 °, and there is a difference of 24 ° between + 12 ° and + 36 °. , It is detected as noise, and the occurrence of misreading can be sufficiently avoided. Further, since the size can be designed to be the same as that of the conventional marker 2, for example, the variation of the marker can be easily increased, and the productivity of the marker mounting unit and the marker can be improved.

As a more detailed example, FIG. 6 shows a schematic diagram regarding the presence or absence of the occurrence of the image on the second lap. 6 (A) is a schematic view showing an image of the second lap of the conventional marker 3 shown in FIG. 3, and FIG. 6 (B) is an image of the second lap of the marker 1 of the present invention shown in FIG. It is a schematic diagram which shows. The conventional marker 3 and the marker 1 of the present invention have the same target angle range for detection in the first lap. In this case, in both the conventional marker 3 and the marker 1 of the present invention, for example, the optical axis changes from an inclination to the right to an inclination to the left from the central axis of the marker due to rotation in the angle range. As a result, the image appearing on the lens portion moves from the left side to the right side. Then, when further rotation beyond the target angle range occurs, the conventional marker 3 moves after the first image from the left side moves to the right end, as shown in the uppermost figure of FIG. 6 (A). Further, as shown in the second figure of FIG. 6 (A), a new image appears from the left end, and as shown in the third and fourth figures, the new image moves to the right side. In this way, due to further rotation, the image of the second lap appears while the image of the first lap remains, so that the image of the first lap appears at a small tilt angle or appears at a large tilt angle. It becomes difficult to distinguish whether it is the image of the second lap, and a problem of misrecognition occurs. On the other hand, in the case of the marker 1 of the present invention, as shown in the uppermost figure of FIG. 6A, even if further rotation occurs after the first image moves to the right end, it already appears. The first image is smaller at the right end, as shown in the second figure of FIG. 6 (B), then the first image disappears, as shown in the third and fourth figures, and then. However, at the same angle as the conventional marker 3 shown in FIG. 6 (A), the image of the second lap does not occur.

Further, FIG. 7 shows the angle of the optical axis at which an image is generated at the same position with respect to the conventional marker 3 and the marker 1 of the present invention. 7 (A) is a schematic view showing an image of the conventional marker 3 shown in FIG. 3, and FIG. 7 (B) is a schematic view showing an image of the marker 1 of the present invention shown in FIG. In FIGS. 7A and 7B, the upper figure shows the optical axis when the image of the first lap is generated at the same place of both, and the lower figure shows 2 at the same place as the upper figure. The optical axis when the image of the circumference is generated is indicated by an arrow. Then, the optical axes shown in FIGS. 7 (A) and 7 (B) are shown together with FIG. 7 (C). As shown in FIG. 7C, both the marker 3 and the marker 1 have the same optical axis angle in the first lap (straight arrow). However, the angle of the optical axis at which the image appears at the same position on the second lap is that the optical axis of the marker 3 of the present invention (broken line arrow) is larger than that of the conventional optical axis of the marker 3 (dotted line arrow). , The difference is large with respect to the central axis of 0 degrees. Therefore, as described above, even when the rotation exceeds the target angle range, the difference from the central axis is large, so that the marker of the present invention can be used even if the image of the second lap appears. It will be a point when it deviates significantly from the target angle range. Therefore, erroneous recognition can be sufficiently prevented.

Further, a marker such as a VMP marker is usually mounted by being inserted into a through hole of a main body serving as a substrate, and is used as a marker mounting unit. However, since it is inserted into the main body, the thickness of the main body generally depends on the thickness of the mounted marker. That is, the thicker the marker, the thicker the main body, and the larger the marker mounting unit becomes. Further, when two types of markers (VMP markers) having different detection angle ranges are mounted on one main body, the thickness of the markers also differs depending on the target detection angle, as illustrated in FIG. In that case, in order to use markers having different thicknesses together, the thickness of the main body must be adjusted according to the thicker marker. On the other hand, in the present invention, for example, it is not essential to change the thickness of the marker depending on the detection angle, and it is not essential to increase the thickness. Therefore, according to the present invention, the thickness of the main body of the marker (VMP marker) of the present invention and the main body of the unit on which the marker (VMP marker) is mounted can be made the same. Therefore, according to the present invention, for example, the size of the marker itself can be reduced regardless of the detection angle, and the marker-mounted unit on which the marker is mounted can be made smaller than the conventional marker-mounted unit. You can also.

Therefore, the marker mounting unit of the present invention includes a substrate and a pair of markers, and one of the pair of markers is the marker of the present invention having a detection angle different from that of the other marker. The pair of markers are inserted into the recesses of the substrate. Specifically, the substrate has, for example, a pair of recesses, and each of the pair of markers is inserted into each of the pair of recesses. In the marker mounting unit of the present invention, the marker of the present invention and the substrate can incorporate the description of the marker of the present invention.

[Embodiment 2]
In the marker mounting unit of the present embodiment, the recess may be, for example, a bottomed recess provided on the substrate or a bottomless recess (through hole). In the marker mounting unit of the present embodiment, the markers can be mounted on the substrate by inserting the pair of markers into the recesses.

In the marker mounting unit of the present embodiment, it is preferable that the pair of markers have, for example, substantially the same thickness. As described above, the marker of the present embodiment can be adjusted to a desired detection sensitivity so as to fit in the size of the recess set in the substrate without requiring thickening, for example. Therefore, in the construction of the marker mounting unit, when there is a substrate and a marker that fits in the recess and a marker having a different detection angle as a pair of the markers is mounted, the marker of the present embodiment is the other. The desired detection angle can be achieved with the same size as the marker. As for the pair of markers, one marker may be the marker of the present embodiment, and the other marker may be, for example, the marker of the present embodiment, or the lens as shown in FIG. 3A described above. A marker may be used in which the detected portion is arranged in the entire range up to both ends of the portion.

In the marker mounting unit of the present embodiment, for example, it is preferable that the pair of markers having different detection angles are mounted in parallel. Since the pair of markers have different detection sensitivities, for example, one of them has a narrower detection angle than the other, so that the marker has a relatively high sensitivity, and the other has a wider detection sensitivity than the other. , It is possible to detect in a relatively wide range. As described above, by mounting the pair of markers having different detection characteristics based on the detection angle on the same substrate in parallel, the marker mounting unit of the present embodiment becomes a marker having more excellent measurement accuracy.

Further, the marker mounting unit of the present embodiment may further mount the markers in a direction different from the direction in which the pair of markers are mounted. The different directions are not particularly limited, and for example, orthogonal directions are preferable.

Here, an example of the marker-mounted unit of the present embodiment will be given, and the difference from the conventional marker-mounted unit will be described with reference to the drawings.

First, FIG. 8 shows a marker mounting unit including a pair of markers having different detection angles. In FIG. 8, (A) is a conventional marker-mounted unit, and (B) is a marker-mounted unit of the present embodiment. In FIGS. 8A and 8B, the first is a top view, the second is a side view, the third is a separated sectional view in the IIA-IIA direction, and the fourth is a separated sectional view in the IIB-IIB direction. ..

The conventional marker mounting unit 200 of FIG. 8A includes a substrate 5 and two pairs of markers (2/3, 6/6). The substrate 5 has an upper substrate 51 and a lower substrate 52. The upper substrate 51 has circular through holes at four corners, and has a pair of rectangular through holes parallel to the X-axis direction and a pair of rectangular through holes W parallel to the Y-axis direction between the through holes. The center of the upper surface is an arrangement portion of the two-dimensional marker such as AR. The lower substrate 52 has convex portions protruding upward at locations corresponding to the through holes at the four corners of the upper substrate 51. The lower substrate 52 and the upper substrate 51 are laminated so that the convex portions at the four corners are inserted into the through holes at the four corners. The upper surface of the convex portion of the lower substrate 52 is exposed at the through holes at the four corners of the upper substrate and serves as the detection reference portion 520. In the substrate 5 in which the lower substrate 52 and the upper substrate 51 are laminated, the two pairs of markers (2/3, 6/6) are formed in the gaps W formed by the two pairs of through holes W of the upper substrate 51 on the lower substrate 52. Is inserted.

In the conventional marker mounting unit 200, when a pair of markers arranged in parallel in the X-axis direction are markers having different detection angles, there are the following problems. Hereinafter, an example in which markers having different detection angles are mounted in parallel in the X direction will be given. However, the markers 6 mounted along the Y-axis direction may be, for example, one or two, and the detection angle may be one. Is not particularly limited.

When mounting markers having different detection angles in parallel in the X direction, for example, one is made a high-sensitivity marker (high-sensitivity marker) by making the width of the detection angle narrower than the other, and the other is used. It is conceivable to use a marker (wide-angle compatible marker) capable of detecting a detection angle having a wider width than one of them. However, the gap W for the marker on the substrate 5 generally has the same length and width in consideration of the overall size of the marker mounting unit 200 and the balance between the two-dimensional marker and the detection reference unit. Therefore, in order to make a pair of markers having the same length and width have different detection angles, it is necessary to change the focal length of the markers to the detected portion 12, so that the pair of markers must have different thicknesses. Specifically, when the upper marker 3 in FIG. 8A is a high-sensitivity marker having a narrower detection angle than the lower marker 2, the marker 3 is as shown in the third cross-sectional view. The thickness in the Z-axis direction is thicker than that of the marker 2 in the fourth cross-sectional view. The gap W in the substrate 5 is deeper in the Z-axis direction than the gap W in the fourth cross-sectional view for mounting the marker 2. There is a need to. Therefore, since the thickness of the markers mounted on the same substrate 5 is different, it is necessary to change the void W for each marker. Further, since the thickness of the marker 3 becomes thick, the total thickness of the marker mounting unit 200 also becomes thick depending on the thickness of the marker 3.

On the other hand, the marker mounting unit 100 of the present embodiment has, as a basic structure, a substrate 4 in which the upper substrate 41 is laminated on the lower substrate 42 and two pairs of markers (2/1, 6 /) as the marker mounting unit 200. 6), the detection reference unit 420 is provided on the upper surface of the upper substrate 41, and the two pairs of markers (2/1, 6/6) are inserted into the gap W. However, similarly to the marker mounting unit 200, when mounting a pair of markers (2/1) having different detection angles, it is possible to avoid the problem of thickness as in the marker mounting unit 200. That is, specifically, when the upper marker 1 in FIG. 8B is a high-sensitivity marker having a narrower detection angle than the lower marker 2, as shown in the third and fourth cross-sectional views. In addition, the markers 1 and 2 can be set to have the same thickness.

This is due to the following reasons. Here, FIG. 9 shows a schematic view of a pair of markers having different detection angles in FIG. 8A and 8B are cross-sectional views of a pair of markers 3 and 2 in the conventional marker-mounted unit 200, and FIG. 8B is a cross-sectional view of the pair of markers 1 and 2 in the marker-mounted unit 100 of the present embodiment. It is a figure. In FIGS. 9A and 9B, the marker 2 is the same marker shown in FIG. 3A, and as described above, the detected portion 12 is the entire area from the central axis to both ends of the lens portion. It is located in the area. The marker 3 in FIG. 8 (A) is the same as the marker in FIG. 3 (B), and the arrangement of the detected unit 12 is the same as that in the marker 2 in the entire region. Therefore, the thickness is thicker than that of the marker 2. On the other hand, the marker 1 of FIG. 9B in the marker mounting unit 100 of the present embodiment is the same as the marker 1 of FIG. 1, and is different from the marker 3 of the conventional marker mounting unit 200, and corresponds to each lens unit. The center of each detected portion 12 is within a region of 1/2 of _{the length (LL} ) of the lens portion 11 in the X-axis direction about the central axis of the lens portion. Therefore, unlike the marker 3, it is not necessary to make the thickness thicker than that of the marker 2, and by setting the arrangement of the detected portion 12 as the above condition, the thickness can be kept the same as that of the marker 2. Therefore, unlike the conventional marker mounting unit 200, the marker mounting unit 100 of the present embodiment can mount a pair of markers having different detection angles, for example, and can make the thicknesses of the markers uniform. It is also possible to avoid increasing the thickness of the entire marker mounting unit.

The marker mounting unit of the present embodiment may include, for example, a two-dimensional pattern code as described above in addition to the marker.

The two-dimensional pattern code is not particularly limited, and examples thereof include an AR marker and a QR marker. Examples of the AR marker include ARTToolKit, ARTag, CyberCode, ARTToolKitPlus and the like. The two-dimensional pattern code may be arranged on the substrate together with the marker of the present invention, for example, as described above.

Although the invention of the present application has been described above with reference to the embodiment, the invention of the present application is not limited to the above embodiment. Various changes that can be understood by those skilled in the art can be made within the scope of the present invention in terms of the structure and details of the present invention.

This application claims priority on the basis of Japanese application Japanese Patent Application No. 2019-12969 filed on November 26, 2019, and incorporates all of its disclosures herein.

As described above, as described above, the marker of the present invention can use the existing marker mounting unit by keeping the position of the detected portion within a predetermined range of the lens portion in the entire marker. Moreover, the range of the target detection angle can be narrowed. Specifically, for example, it is possible to avoid an increase in the thickness of the lens portion and narrow the range of the detection angle while maintaining the size of the marker assumed in the existing marker mounting unit. Therefore, according to the marker of the present invention, for example, the variation of the detection angle range can be easily set, and the productivity of the marker and the marker mounting unit can be improved.

1, 2, 3, 6 Marker 11 Lens part 12, 121, 122, 123 Detected part 4, 5 Board 41, 51 Upper board 42, 52 Lower board 420, 520 Detected part W void

Claims (4)

Including the lens body
The lens body has a plurality of lens portions on one surface side and a plurality of detected portions on the other surface side.
The plurality of lens portions are continuously arranged in the one-dimensional direction at a constant pitch on one surface side thereof.
The plurality of detected portions are arranged on the other surface side at a constant pitch at intervals in the same one-dimensional direction.
The pitches of the plurality of lens portions and the pitches of the plurality of detected portions are different.
Each of the lens portions corresponds to each of the detected portions, and corresponds to each of the detected portions.
The feature is that the center of the detected portion is arranged in a region having a length of 1/2 of the total length of the lens portion in the one-dimensional direction with respect to the central axis of the lens portion. Marker to do. The first aspect of the present invention, wherein the center of the detected portion is arranged in a region having a length of 1/3 of the lens portion about the central axis of the lens portion in the one-dimensional direction. Marker. The first or second aspect of the present invention, wherein the lens body is a cylindrical lens in which the lens portion is continuous only in the one-dimensional direction, or a lens array in which the lens portion is continuous in the one-dimensional direction and the direction intersecting the one-dimensional direction. Marker. Includes a substrate with recesses and a pair of markers
The marker according to any one of claims 1 to 3, wherein one of the pair of markers has a different detection angle from the other marker.
A marker mounting unit characterized in that the pair of markers is inserted into a recess of the substrate.

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