CN117769637A

CN117769637A - Measuring system

Info

Publication number: CN117769637A
Application number: CN202280053775.8A
Authority: CN
Inventors: 鹿岛启二; 古川正; 大川晃次郎; 谷口幸夫; 藤崎英明
Original assignee: Dai Nippon Printing Co Ltd
Current assignee: Dai Nippon Printing Co Ltd
Priority date: 2021-08-05
Filing date: 2022-07-19
Publication date: 2024-03-26

Abstract

The invention provides a measuring system which is easy to manufacture and can perform high-precision measurement. The mark (1) measured by the measurement system (500) is provided with: a base material layer (10); a 1 st layer (20) which is laminated on one surface of the base material layer (10) and is observed as a 1 st color; and a 2 nd layer (30) which is partially laminated on the 1 st layer (20), is observed as a 2 nd color different from the 1 st color, and partially shields the 1 st layer (20), the 1 st layer (20) being observable in a region where the 2 nd layer (30) is not laminated, the 2 nd layer (30) being composed of a resist material.

Description

Measuring system

Technical Field

The present invention relates to measurement systems.

Background

Various automatic control devices attach a mark to an object in order to identify the object, thereby realizing high-precision automatic control. Such markers are used, for example, for the control of robots in production sites or for cosmic tasks.

Conventionally, as an example of such a mark, a mark in which a mark is printed on paper has been widely used for the reason that such a mark can be easily produced. However, in such a simple mark, when the boundary line of the mark is not clear or the size of the mark or the interval between a plurality of marks is changed by the expansion and contraction of paper, high precision control is required, a sufficient precision cannot be ensured.

Accordingly, as a technique for realizing a high-precision marking, patent document 1 discloses a technique for forming a hole in a metal plate by cutting and embedding a resin as a marking. However, in the technique of patent document 1, since the precision of machining needs to be set to be high, the production of the marker takes a lot of effort, and there is a limit in improving the precision.

Prior art literature

Patent literature

Patent document 1: japanese patent laid-open No. 5-312521

Disclosure of Invention

Problems to be solved by the invention

The invention provides a measuring system which is easy to manufacture and can measure with high precision.

Means for solving the problems

The present invention solves the above problems by the following means. For ease of understanding, reference numerals corresponding to the embodiments of the present invention are given to the description, but the present invention is not limited thereto.

The 1 st invention is a measurement system (500) provided with: a marker (1, 1B, 1C); an imaging unit (201) that images the marks (1, 1B, 1C); and a calculation unit (202) that calculates at least one of a relative positional relationship between the imaging unit (201) and the marks (1, 1B, 1C), a size of an object in the vicinity of the marks (1, 1B, 1C) or a distance between specified positions, a distance between the marks (1, 1B, 1C) in which a plurality of marks are arranged, and a posture of the marks (1, 1B, 1C) using the image of the marks (1, 1B, 1C) imaged by the imaging unit (201), wherein the marks (1, 1B, 1C) include: a base material layer (10); a 1 st layer (20, 20C) which is laminated on the observation side of the base material layer (10) and is observed as a 1 st color; and a 2 nd layer (30, 30C) which is partially laminated on the observation side of the 1 st layer (20, 20C), is observed as a 2 nd color different from the 1 st color, and partially shields the 1 st layer (20, 20C), the 1 st layer (20, 20C) being observable in a region where the 2 nd layer (30, 30C) is not laminated, the 2 nd layer (30, 30C) being composed of a resist material.

The 2 nd invention is a measurement system (500), characterized in that according to the measurement system (500) according to the 1 st invention, the 1 st layer (20, 20C) is composed of a resist material.

The 3 rd invention is a measurement system (500) comprising: a marker (1, 1B, 1C); an imaging unit (201) that images the marks (1, 1B, 1C); and an arithmetic unit (202) for calculating the imaging unit (201) and the image of the mark (1, 1B, 1C) imaged by the imaging unit (201)At least one of a relative positional relationship of the marks (1, 1B, 1C), a size of an object in the vicinity of the marks (1, 1B, 1C) or a distance between specified positions, a distance between the marks (1, 1B, 1C) in which a plurality of the marks (1, 1B, 1C) are arranged, and a posture of the marks (1, 1C), wherein the marks (1, 1B, 1C) are provided with: a base material layer (10); a 1 st layer (20, 20C) which is laminated on the observation side of the base material layer (10) and is laminated on the entire surface of the base material layer (10) and which is observed as the 1 st color; and a 2 nd layer (30, 30C) which is partially laminated on the observation side of the 1 st layer (20, 20C), is observed as a 2 nd color different from the 1 st color, and partially shields the 1 st layer (20, 20C), the 1 st layer (20, 20C) being observable in a region where the 2 nd layer (30, 30C) is not laminated, the linear expansion coefficient of the base material layer (10) being 10×10 ^-6 And/or lower.

The 4 th aspect of the present invention is the measurement system (500) according to any one of the 1 st aspect to the 3 rd aspect of the present invention, wherein the base material layer (10) is made of glass.

The 5 th aspect of the present invention is the measurement system (500) according to any one of the 1 st to 4 th aspects of the present invention, wherein one of the 1 st layers (20, 20C) and the 2 nd layers (30, 30C) is observable as marks (2) having independent shapes, and the marks (2) are arranged at 3 or more intervals.

The 6 th aspect of the present invention is a measurement system (500) according to the 5 th aspect of the present invention, wherein a pattern (5) for identification is arranged in the measurement system (500), and the arithmetic unit (202) identifies the marks (1, 1B, 1C) by referring to the pattern (5).

The 7 th aspect of the present invention is a measurement system (500), wherein in the measurement system (500) according to the 6 th aspect of the present invention, the arithmetic unit (202) performs arithmetic processing as follows: a 1 st arithmetic processing of calculating at least one of a relative positional relationship between the imaging unit (201, 450) and the marker (1), a size of an object in the vicinity of the marker (1) or a distance between specified positions, a distance between the markers (1) in which a plurality of the markers are arranged, and a posture of the marker (1), based on an image of the marker (2) included in the image of the marker (1); and a 2 nd arithmetic processing of calculating at least one of a relative positional relationship between the imaging unit (201, 450) and the marker (1), a size of an object in the vicinity of the marker (1) or a distance between specified positions, a distance between the markers (1) where a plurality of the markers are arranged, and a posture of the marker (1) based on an image of the recognized figure (5) included in the image of the marker (1).

The 8 th aspect of the present invention is the measurement system (500) according to the 7 th aspect of the present invention, wherein the arithmetic unit (202) outputs the arithmetic result of the 1 st arithmetic processing when the 1 st arithmetic processing is able to perform arithmetic appropriately, and outputs the arithmetic result of the 2 nd arithmetic processing when the 1 st arithmetic processing is not able to perform arithmetic appropriately.

The 9 th aspect of the present invention is the measurement system (500) according to the 8 th aspect of the present invention, wherein the arithmetic unit (202) performs the 1 st arithmetic processing and the 2 nd arithmetic processing in parallel.

The 10 th aspect of the present invention is a measurement system (500) according to any one of the 1 st to 3 rd aspects of the present invention, wherein the measurement system (500) includes a control unit (203), and the control unit (203) controls the measurement system based on a result of the calculation by the calculation unit (202).

The 11 th aspect of the present invention is the measurement method of the measurement system (500) according to any one of the 1 st aspect to the 3 rd aspect of the present invention, wherein the measurement method of the measurement system (500) comprises the steps of: the photographing section (201) photographs the marks (1, 1B, 1C); and the computation unit (202) uses the image of the marks (1, 1B, 1C) captured by the capture unit (201) to compute at least one of the relative positional relationship between the capture unit (201) and the marks (1, 1B, 1C), the size of an object in the vicinity of the marks (1, 1B, 1C) or the distance between specified positions, the distance between the marks (1, 1B, 1C) where a plurality of marks are arranged, and the posture of the marks (1, 1B, 1C).

The 12 th invention is the program of the measurement system (500) according to any one of the 1 st to 3 rd inventions, wherein the program of the measurement system (500) is configured to cause a computer (202, 203) to execute: the photographing section (201) photographs the marks (1, 1B, 1C); and the computation unit (202) uses the image of the marks (1, 1B, 1C) captured by the capture unit (201) to compute at least one of the relative positional relationship between the capture unit (201) and the marks (1, 1B, 1C), the size of an object in the vicinity of the marks (1, 1B, 1C) or the distance between specified positions, the distance between the marks (1, 1B, 1C) where a plurality of marks are arranged, and the posture of the marks (1, 1B, 1C).

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, a mark that is easy to manufacture and has high accuracy can be provided.

Further, according to the present invention, a mark capable of displaying moire brightly can be provided.

Further, according to the present invention, it is possible to provide a mark that can be easily recognized even in an environment where sunlight, illumination light, or the like is irradiated on the mark.

Drawings

Fig. 1 is a diagram showing a mark 1 according to embodiment 1.

Fig. 2 is a cross-sectional view of the mark cut at the position of arrow A-A in fig. 1.

Fig. 3 is a diagram showing a manufacturing process of the mark 1.

Fig. 4 is a partially enlarged view of the result of capturing the mark 2 of the present embodiment and the comparative example.

Fig. 5 is a graph showing a change in light intensity with respect to a change in position at the boundary of black of the 1 st layer 20 and white of the 2 nd layer 30.

Fig. 6 is a diagram showing a mark 1B of embodiment 2.

Fig. 7 is a diagram showing a mark 1C according to embodiment 3.

Fig. 8 is a cross-sectional view of the mark cut at the position of arrow B-B in fig. 7.

Fig. 9 is a diagram showing a manufacturing process of the mark 1C. Fig. 9 shows the reverse and forward (up and down) directions, as opposed to fig. 8.

Fig. 10 is a diagram showing the multi-surface tag arrangement 100.

Fig. 11 is a diagram showing a mode in which the electrode layer 95 is provided.

Fig. 12 is a diagram showing a modification of embodiment 1 in which layer 1 20 is white and layer 2 30 is black.

Fig. 13 is a diagram showing a modification of embodiment 1 in which layer 1 20 is white and layer 2 30 is black.

Fig. 14 is a diagram showing a modification of embodiment 3 in which layer 1 20C is black and layer 2 30C is white.

Fig. 15 is a diagram showing a modification of embodiment 3 in which layer 1 20C is black and layer 2 30C is white.

Fig. 16 is a cross-sectional view showing a modification of the embodiment 1 in which a planarizing layer 91 is provided in an opening 30a of the layer 2 30.

Fig. 17 is a diagram showing embodiment 4 of the mark of the present invention.

Fig. 18 is a cross-sectional view of the mark cut at the position of arrow A-A in fig. 17.

Fig. 19 is a view in which the vicinity of the 2 nd pattern 43 is enlarged for explaining the cause of occurrence of unwanted moire.

Fig. 20 is a diagram illustrating details of the 1 st pattern 23 and the 2 nd pattern 43.

Fig. 21 is a diagram showing a state in which the marker 1 is viewed from an oblique direction.

Fig. 22 is a diagram showing embodiment 5 of the mark of the present invention.

Fig. 23 is a cross-sectional view of the mark cut at the position of arrow A-A in fig. 22.

Fig. 24 is a graph showing the effect of the light diffusion layer 80.

Fig. 25 is a diagram showing a state in which the marker 1 is viewed from an oblique direction.

Fig. 26 is a diagram showing a modification of the color of the 1 st layer 20 and the 2 nd layer 30.

Fig. 27 is a diagram showing embodiment 6 of the mark of the present invention.

Fig. 28 is a diagram showing a tray P to which embodiment 6 of the mark 1 is attached.

Fig. 29 is a diagram showing a measurement system 500 including a marker 1 of embodiment 6.

Fig. 30 is a flowchart showing a flow of control operations of the forklift 200 using the measurement system 500 according to the present embodiment.

Fig. 31 is a diagram showing embodiment 7 of the mark of the present invention.

Fig. 32 is a diagram showing a multi-surface marker array 100 according to embodiment 7.

Fig. 33 is a diagram showing a tray P to which a mark 1 of embodiment 7 is attached.

Fig. 34 is a diagram showing a measurement system 500 including a mark 1 of embodiment 7.

Fig. 35 is a flowchart showing a flow of control operations of the forklift 200 using the measurement system 500 according to the present embodiment.

Fig. 36 is a diagram showing a state in which a part of the marker 2 is not properly photographed due to an obstacle.

Fig. 37 is a diagram showing a 1 st modification of the usage pattern of the mark 1 according to embodiment 7.

Fig. 38 is a diagram showing a 2 nd modification of the usage pattern of the mark 1 according to embodiment 7.

Detailed Description

The best mode for carrying out the present invention will be described below with reference to the accompanying drawings.

In the measurement system of the present invention, the form of the mark is important by taking a picture of the mark with a camera to accurately measure the relative positional relationship between the mark and the camera, and the like. Therefore, first, the following embodiments 1 to 6 will illustrate examples of specific forms of the markers, and a measurement system including the marker 1 of embodiment 6 will be described.

(embodiment 1)

Fig. 1 is a diagram showing a mark 1 according to embodiment 1.

The drawings shown below, including fig. 1 and 2, are schematically shown, and the size and shape of each part are appropriately exaggerated or omitted for easy understanding.

In the following description, specific numerical values, shapes, materials, and the like are shown and described, but these may be appropriately changed.

In the present specification, the terms plate, sheet, film and the like are used, but these are used as general methods of use in order of thickness from thick to thin, and are used in this specification in a manner similar to this. However, such a distinction is not technically significant, and therefore these terms can be appropriately replaced.

In the present invention, transparent means transmitting at least light of a wavelength to be used. For example, even if visible light is not transmitted, if infrared light is transmitted, the light is considered to be transparent when used for infrared applications.

The specific numerical values set forth in the specification and claims should be construed as including general error ranges. That is, the difference of about ±10% is not substantially different, and the numerical value is set within a range slightly exceeding the numerical value range of the present application, which should be interpreted as being substantially within the scope of the present invention.

As shown in fig. 1, the mark 1 is formed in a substantially square plate shape when viewed from a normal direction of a front surface provided with a protective layer 70 described later, and the mark 1 is provided with a plurality of marks 2. In the present embodiment, the shape as viewed from the front side is formed in a substantially square shape of 60mm×60mm (having a chamfer shape at each corner), and the round marks 2 are arranged one at each of the vicinity of the 4 corners of the mark 1, and four marks in total are arranged at intervals. The number of marks 2 is preferably at least 3. This is because, for example, if the position of the center of gravity of the 3-point mark 2 is calculated from the observation result of the mark 2, the relative position, slope, and posture of the observation position (camera or the like) and the mark 1 can be accurately detected. If the number of marks 2 is greater than 3, for example, if some marks 2 are not clearly observed due to some obstacle, position detection can be performed based on the observation results of the remaining marks 2. In addition, by using a plurality of marks 2, the accuracy of position detection can be improved.

The mark 1 is attached to a side surface of a measurement object such as a pallet on which a load is placed, for example, and is used for automatic driving control of an automatic driving forklift equipped with a camera. That is, the relative positional relationship between the forklift and the pallet can be accurately grasped from the imaging result of the camera, and the driving of the forklift can be controlled based on the relative positional relationship. For such applications, the size of the marker 1 as viewed from the front side is preferably 100mm×100mm or less, but according to the marker 1 of the present embodiment, even with such a small size, it is possible to perform very high-precision position detection.

The outer shape of the marker 1 is not limited to the above example, and may be appropriately changed to, for example, 10mm×10mm, 20mm×20mm, 40mm×40mm, 44mm×44mm, 80mm×80mm, or the like.

In the present embodiment, the symbol 2 is formed in a circular shape, but the shape is not limited to a circular shape, and may be a polygonal shape such as a triangle or a quadrangle, or may be other shapes. The label 1 is used for the following purposes: the relative positional relationship between the imaging position and the mark 1 is detected based on how the mark 2 is observed (hereinafter also simply referred to as position detection).

The label 1 is formed in a thin plate shape by stacking the base material layer 10, the 1 st layer 20, the 2 nd layer 30, the adhesive layer 60, and the protective layer 70 in this order from the back surface side. In the description of the present specification and claims, the term "stacked" is not limited to a case of being directly stacked, but includes a case of being stacked with other layers interposed therebetween. In fig. 2, the upper side (side where the protective layer 70 is provided) is the observation side (front side).

The substrate layer 10 is made of a glass plate. By forming the base material layer 10 from a glass plate, the expansion and contraction of the marker 1 due to temperature change or moisture absorption can be suppressed. The glass plate has a linear expansion coefficient of, for example, 31.7X10 ^-7 about/deg.C, the dimensional change due to the temperature change is very small.

The glass plate of the base material layer used in the present embodiment is Corning (registered trademark) EAGLE XG (registered trademark) and has a linear expansion coefficient of 3.17×10 ^-6 /℃。

The linear expansion coefficient of the glass plate was measured in accordance with JIS R3102.

The linear expansion coefficient of the ceramic is, for example, 28×10 ^-7 about/DEG C, the dimensional change due to the temperature change is very small as in glass. Therefore, ceramics may also be used for the substrate layer. In order to suppress dimensional change due to temperature change, the linear expansion coefficient of the base material layer 10 is preferably 10×10 ^-6 And/or lower.

As an example of a ceramic that can be used as a base material layer, silicon nitride (linear expansion coefficient of 2.8x10 ^-6 /(deg.C). Specifically, a DENKA SN plate (manufactured by DENKA corporation) may be exemplified. Examples of ceramics that can be used as the base layer include alumina substrates (96% alumina (manufactured by Nikko corporation), alumina zirconia substrates (manufactured by MARURA corporation), and aluminum nitride substrates (manufactured by MARURA corporation).

In the case of ceramics, the linear expansion coefficient was measured in accordance with JIS R1618.

The thickness of the base material layer 10 is preferably 0.3mm or more and 2.3mm or less. This is because if the layer thickness of the base material layer 10 is less than 0.3, the base material layer will break during the cutting process, and therefore additional processing will not be performed, and if it is 2.3 or more, the weight will be too large to convey if the base material layer is a multi-sided substrate as will be described later.

The 1 st layer 20 is formed of a resist material colored black (1 st color), and is laminated on the entire surface of the base material layer 10. In fig. 2, the hatching indicates black, and the same applies to other cross-sectional views described below.

In the description of the present specification and claims, the "resist material" means a resin composition material having photosensitivity containing a pigment or a dye. The resist material constituting the 1 st layer 20 of the present embodiment is: as a result of developing a resist material having photosensitivity used in a photolithography process, the resist material is in a state after photosensitivity is lost. As a resist material used for the 1 st layer 20 (in the case of black), PMMA, ETA, HETA, HEMA or a mixture with an epoxy resin is exemplified. Examples of the material to be colored black include carbon, titanium black, nickel oxide, and the like.

In this embodiment, since the 1 st layer 20 is formed of a resist material, the surface of the 1 st layer 20 can be formed very smoothly, and it is preferable as a substrate for forming the 2 nd layer 30 described later. In addition, since an alignment mark (not shown) at the time of forming the 2 nd layer can be formed on the outer peripheral portion of the 1 st layer 20, dimensional accuracy can be improved.

The layer thickness of the 1 st layer 20 (in the case of black) is preferably 1 μm or more and 5 μm or less. This is because the layer thickness of the 1 st layer 20 is not uniformly formed at 1 μm or less, and the curing reactivity of the resin by ultraviolet rays is insufficient at 5 μm or more.

The 2 nd layer 30 is formed of a resist material colored white (2 nd color), and is partially laminated on the 1 st layer 20 with openings. The resist material constituting the layer 2 30 of the present embodiment is: as a result of developing a resist material having photosensitivity used in a photolithography process, the resist material is in a state after photosensitivity is lost. As a resist material used for the 2 nd layer 30 (in the case of white), PMMA, ETA, HETA, HEMA or a mixture with an epoxy resin is exemplified. Examples of the material colored in white include titanium oxide, zirconium oxide, and barium titanate.

The 2 nd layer 30 is provided with an opening 30a at 4 places, which is partially opened by a photolithography process described later to visualize the 1 st layer 20. That is, the 2 nd layer 30 partially shields the 1 st layer 20, and the region not shielded (the region where the 2 nd layer 30 is not laminated) is the opening 30a. The region of the 1 st layer 20 visualized through the opening 30a is configured to be observable as a mark 2 of an independent shape. The symbol having an independent shape means that a plurality of symbols are not connected to each other but are individually identifiable.

The layer thickness of the 2 nd layer 30 (in the case of white) is preferably 3 μm or more and 100 μm or less. This is because, if the layer thickness of the 2 nd layer 30 is smaller than 3 μm, the 1 st layer 20 of the substrate is observed therethrough, and the contrast is lowered, and the visibility of the mark 2 (detection easiness by automatic recognition) is lowered. Further, if the layer thickness of the 2 nd layer 30 is thicker than 100 μm, when the mark 2 is observed from an oblique direction, the region where the 1 st layer 20 is not seen increases due to the shadow of the 2 nd layer 30 at the peripheral edge portion of the opening 30a, and the deformation of the shape of the observed mark 2 increases.

Regarding the mark 2, the contrast value of the color of the 1 st layer 20 and the color of the 2 nd layer 30 is higher, which is preferable for higher-precision detection. In the structure of the present embodiment used in white light (visible light), it is preferable that the contrast value between the color of the 1 st layer 20 (1 st color) and the color of the 2 nd layer 30 (2 nd color) is 0.26 or more, and the observed blur value between the color of the 1 st layer 20 (1 st color) and the color of the 2 nd layer 30 (2 nd color) is 0.17 or more. The contrast value and the blur value will be described later with reference to fig. 5.

The adhesive layer 60 is a layer of adhesive for adhering the protective layer 70 to the 2 nd layer 30. The adhesive layer 60 is composed of a transparent adhesive so that the 1 st layer 20 and the 2 nd layer 30 can be observed. The adhesive layer 60 is formed of, for example, PMMA, polyurethane, silicone, or the like.

The thickness of the adhesive layer 60 is preferably 0.5 μm or more and 50 μm or less. This is because, if the layer thickness of the adhesive layer 60 is less than 0.5 μm, it is difficult to achieve uniform processing and the irregularities of the substrate cannot be absorbed. In addition, if the layer thickness of the adhesive layer 60 is thicker than 50 μm, the solvent removal at the time of thick coating process takes much effort and the cost becomes high. The layer thickness of the adhesive layer 60 here means the layer thickness at the position where the thickness is the thinnest.

The protective layer 70 is a layer for protecting the 1 st layer 20 and the 2 nd layer 30, and is adhered to the 2 nd layer 30 via the adhesive layer 60. The protective layer 70 has a resin base layer 71 and a front layer 72. The resin base layer 71 may be formed using, for example, vinyl chloride, polyethylene terephthalate, polycarbonate, cyclic olefin polymer, triacetyl cellulose, or the like. For example, an acrylic resin, sol-gel, silicone, polysilazane, or the like having a property of diffusing light by mixing fine particles may be used for the front surface layer 72, but when the front surface of the resin base layer 71 is embossed or the like to form the front surface into a concave-convex shape and impart a property of diffusing light, the front surface layer 72 may be omitted. Further, by adding light diffusion to the protective layer 70 as described above, the function as a light diffusion layer can be provided.

The resin base layer 71 has the adhesive layer 60 laminated on one surface and the front surface layer 72 laminated on the other surface. The resin base layer 71 is made of a transparent resin so that the 1 st layer 20 and the 2 nd layer 30 can be observed.

In the present embodiment, it is assumed that the adhesive layer 60 and the resin base layer 71 are configured to be transparent to white light by the mark 1 under visible light. Specifically, the adhesive layer 60 and the resin base material layer 71 are preferably each: the total light transmittance in the region where the wavelength of light is 400nm to 700nm is 50% or more. More preferably, the total light transmittance in a region where the wavelength of light is 400nm to 700nm is 50% or more in a state where the adhesive layer 60 and the resin base material layer 71 are measured together.

The thickness of the resin base layer 71 is preferably 7 μm or more and 250 μm or less. This is because, if the layer thickness of the resin base layer 71 is less than 7 μm, it is difficult to perform lamination processing. In addition, if the layer thickness of the resin base layer 71 is thicker than 250 μm, the volume and weight become excessively large, and the cost becomes high.

The refractive index of the resin base layer 71 is preferably 1.45 or more and 1.55 or less.

The front layer 72 may be a layer having both an antireflection function and a hard coat function. The positive surface layer 72 has a positive reflectance of 1.5% or less with respect to light having a wavelength of 535nm, and is preferable in order to prevent the visibility of the mark 2 from being lowered by reflection on the front surface of the mark 1. For example, in the case of using annular illumination or the like arranged so as to surround the lens periphery of the camera for observing the marker 1, there may be a case where the illumination itself is reflected on the front surface of the marker 1 and observed. In this case, by preventing or suppressing front reflection by the antireflection function of the front layer 72, the outline of the mark 2 can be recognized more clearly, and high-precision detection can be performed. The hard coat function of the front surface layer 72 is preferably 1H or more in terms of pencil hardness.

The front surface layer 72 may be formed using, for example, sol gel, silicone, polysilazane, or the like.

Specific examples of the antireflection function include an Antireflection (AR) method and an antiglare method (AG), but the AR method is preferable for identifying the symbol 2 under the condition that strong light such as sunlight is not orthographically reflected. Under the condition that strong light such as sunlight is likely to be positively reflected, the AG method is preferable for identifying the symbol 2. The AR method can be produced by a known method such as multilayer thin film interference or moth-eye method, and the AG method can be produced by a known method such as forming the surface of the film into irregularities, mixing particles that diffuse light into the film, and coating the surface of the film.

Further, as a characteristic of combining the adhesive layer 60 and the protective layer 70, it is preferable that the total light transmittance is 85% or more. This is because if the total light transmittance is less than 85%, a sufficient amount of light cannot be ensured.

Further, as a characteristic of combining the adhesive layer 60 and the protective layer 70, a haze value of 30% or more, more preferably 40% or more, and still more preferably 70% or more is desirable. This is because, if the haze value is less than 70%, the antireflection effect starts to decrease, and if it is 40% or less, it is further decreased, and if it is 30% or less, it is significantly decreased. On the other hand, the haze value is preferably 95% or less. This is because, if the haze value is higher than 95%, the image of the observed mark becomes blurred.

Next, a method for manufacturing the mark 1 of the present embodiment will be described.

Fig. 3 is a diagram showing a manufacturing process of the mark 1. In fig. 3, the front and back (up and down) are shown as opposed to fig. 2.

First, a glass plate is prepared as the base material layer 10 ((a) of fig. 3).

Next, a black colored resist material (layer 1 forming step) as a raw material of layer 1 20 is applied to one surface of the base layer 10, and cured by pre-baking, and then exposed to light by a light source LS (layer 1 developing step), developed, and post-baked (layer 1 baking step), whereby layer 1 20 is stabilized (fig. 3 (b)).

Next, a white colored resist material as a material of the layer 2 30 is applied on the layer 1 20 (layer 2 forming step), and is prebaked to be cured (fig. 3 (c)).

Next, the mask M is brought into close contact with the cured layer 2 30, and a mark pattern is exposed on the layer 2 30 (the 2 nd exposure step) (fig. 3 (d)). A mask pattern is formed in advance on the mask M, and a portion of the mask pattern other than the portion corresponding to the mark 2 is transmitted through, and the portion corresponding to the mark 2 is blocked from light.

Next, the exposed 2 nd layer 30 is developed to remove the resist material at the position corresponding to the mark 2, thereby forming an opening 30a (2 nd development step) (fig. 3 (e)). After development, the 2 nd layer 30 is post-baked (2 nd baking step).

Finally, a film-like or sheet-like protective layer 70 prepared separately is adhered to the 2 nd layer 30 via the adhesive layer 60, thereby completing the mark 1 ((f) of fig. 3).

Since the mark 1 of the present embodiment uses a resist material, the outline shape of the mark 2 can be manufactured with very high accuracy, and control with higher accuracy can be performed based on the observed shape of the mark 2. In order to easily understand this fact, the outline shape of the mark 1 of the present embodiment and the comparative example are actually produced, and the result of the comparison is shown below.

In the comparative example, the shape of the mark 2 was printed on paper using a laser printer.

Fig. 4 is a partially enlarged view of the result of capturing the mark 2 of the present embodiment and the comparative example. Fig. 4 (a) shows the present embodiment, and fig. 4 (b) shows a comparative example. Fig. 4 shows a case where the intermediate value between black and white is binarized as a threshold value.

For the imaging of symbol 2, a digital microscope VHX-5500 (1/1.8 CMOS image sensor, effective pixel 1600 (H) ×1200 (V)) manufactured by ken corporation was used. The distance between the mark 2 and the end of the lens at the time of photographing was 15mm.

As shown in fig. 4, the outline shape of the peripheral edge portion of the mark 2 of the mark 1 of the present embodiment is represented by a very smooth curve (arc). In contrast, in the comparative example, even though the outline looks like a circle at a distance, the outline shape is greatly deformed from an arc when viewed in enlargement.

In fig. 4, binarization is performed and no representation is performed, but in the actual imaging result, the presence of the intermediate gradation instead of the black and white 2 gradations is significant in the comparative example. Therefore, in particular in the comparative example, it is considered that the shape grasped as the external shape of the mark 2 is not preferable because it varies depending on the imaging conditions (observation conditions) and the determination method (threshold value) of the boundary between black and white. In order to make it easier to compare this with the case of the present embodiment, the change in light intensity with respect to the change in position at the boundary between black and white is plotted based on the captured data.

Fig. 5 is a graph showing a change in light intensity with respect to a change in position at the boundary of black of the 1 st layer 20 and white of the 2 nd layer 30. In fig. 5, the side with the lower intensity on the vertical axis appears as the black side, and the side with the higher intensity appears as the white side. The horizontal axis corresponds to a pixel of the captured data, but the absolute value itself is not significant because the reference position is shown by being shifted so that the two pieces of broken line data do not overlap. The change in pixel value of the horizontal axis corresponds to the change in position, and 100 pixels corresponds to 1mm. The embodiment and the comparative example in fig. 5 are the same as the embodiment and the comparative example shown in fig. 4, respectively.

As described above, the contrast value between the color of the 1 st layer 20 (1 st color) and the color of the 2 nd layer 30 (2 nd color) is preferably 0.26 or more.

The reason why the contrast value is preferably 0.26 or more is considered to be that: if the contrast value is less than 0.26, automatic detection of the mark 2 using a camera becomes difficult.

Here, when the maximum value of the light intensity is Imax and the minimum value is Imin, the contrast value= (Imax-Imin)/(imax+imin).

In the example shown in fig. 5, the contrast value of the present embodiment is 0.98, and the contrast value of the comparative example is 0.98, and a large difference between the two is not observed.

As described above, the blur value of the observed color of the 1 st layer 20 (1 st color) and the observed color of the 2 nd layer 30 (2 nd color) is preferably 1.0 or more.

In particular, when the control is performed with high accuracy, the boundary of the mark is not desired to be blurred, and therefore, it is preferable that the intensity at the boundary portion between the black side and the white side is changed to be rectangular or changed rapidly.

From the data of fig. 5, the intensity change at the boundary portion of the black side and the white side was compared by digitizing. Specifically, the data of the range shown as LA and LB in the broken line in fig. 5 are quantized with their slopes. Here, the determination method of the ranges LA and LB is set to a range that can be sufficiently linearly approximated. That is, an approximate straight line is obtained for a range where the intensity variation is large, and the ranges where the measured data does not deviate are the above-described ranges LA and LB. In the above ranges LA and LB, (intensity change amount)/(pixel change amount) is obtained as a slope value (blur value) of the intensity change. As a result, in the present embodiment, the slope value (blur value) of the intensity change is 1.29. On the other hand, in the comparative example, the slope value (blur value) of the intensity change was 0.87. In this way, a clear difference was confirmed between the two, and the structure of this embodiment is a preferable mode closer to ideal.

As described above, according to the present embodiment, since photolithography is used, high-precision machining is not required, and the manufacturing can be performed easily, and high-precision marks can be formed.

In addition, the mark 1 according to the present embodiment can make the thickness of the 2 nd layer 30 extremely thin, and can suppress the shape of the mark 2 from being distorted and observed even when viewed from an oblique direction, thereby enabling higher-precision position detection.

(embodiment 2)

Fig. 6 is a diagram showing a mark 1B of embodiment 2.

The mark 1B of embodiment 2 is the same as the mark 1 of embodiment 1 except that the mark 2 is arranged more. Therefore, portions that perform the same functions as those of embodiment 1 are given the same reference numerals, and redundant description is appropriately omitted.

In the mark 1B of embodiment 2, the mark 2 is arranged more than in embodiment 1. Specifically, the marks 2 are arranged in a grid-like manner at intervals on the mark 1B.

As described above, at least 3 marks 2 are preferably arranged. This is because, for example, if the position of the center of gravity of the 3-point mark 2 is calculated from the observation result of the mark 2, the relative position and the slope between the observation position (camera or the like) and the mark 1 can be accurately detected. If the number of marks 2 is greater than 3, for example, if some marks 2 are not clearly observed due to some obstacle, position detection can be performed based on the observation results of the remaining marks 2. In addition, by using a plurality of marks 2, the accuracy of position detection can be improved.

In embodiment 2, the number of marks 2 is 9, and the number of marks 2 is greatly increased as compared with embodiment 1. Thus, in addition to the above effects, the following effects can be expected.

For example, even when a large number of marks 2 are not properly photographed (observed) because more than half of the area of the mark 1B cannot be properly photographed (observed), the possibility of being able to properly perform position detection can be improved by photographing (observing) the remaining marks 2. As a situation in which half or more of the area of the mark 1B cannot be properly photographed (observed), there are, for example, the following: the sunlight directly irradiates more than half of the area of the mark 1B, while the sunlight does not irradiate the remaining area. In such a case, if one of the exposures (gains) is made appropriate, the other one of the exposures is overexposed or underexposed. Further, the following can be exemplified: other objects physically overlap with a part of the photographing optical axis, so that more than half of the area of the mark 1B cannot be photographed (observed).

When the number of marks 2 is assumed to be substantially square as shown in fig. 6, it is preferable to set 9 or more marks because marks 2 are easily and uniformly arranged. The number of marks 2 may be larger, and may be arbitrarily arranged, that is, may be so-called random arrangement, without being limited to uniform arrangement. In addition, in the case of random arrangement, position detection can be easily performed by obtaining the arrangement data of the marks 2 in the marks 1B. Further, by setting the arrangement to be random, even when the relationship between the mark 1B and the imaging position (observation position) is rotated 180 degrees, the relative positional relationship between the two can be accurately grasped.

As described above, according to embodiment 2, the mark 1B has 9 or more marks 2. Therefore, even under more severe photographing conditions (under observation conditions), position detection can be appropriately performed.

(embodiment 3)

Fig. 7 is a diagram showing a mark 1C according to embodiment 3.

The mark 1C of embodiment 3 has the same form as that of embodiment 1, except that the mark is observed in the same form as that of embodiment 1, except that the layer 1 20C is white and the layer 2 30C on the observation side is black, the planarizing layer 91 and the intermediate layer 92 are provided, and the protective layer 70C is provided in a different form. Therefore, the same reference numerals are given to the portions that perform the same functions as those of embodiment 1, and overlapping description is omitted as appropriate.

The label 1C of embodiment 3 is formed in a thin plate shape by stacking the base material layer 10, the 1 st layer 20C, the intermediate layer 92, the 2 nd layer 30C, the adhesive layer 60, and the protective layer 70C in this order from the back surface side. Further, a planarizing layer 91 is provided in a region around the periphery where the 2 nd layer 30C is not provided.

The 1 st layer 20C is formed of a resist material colored white (1 st color), and is laminated on the entire surface of the base material layer 10. In the present embodiment, the base material layer 10 is made of alkali-free glass having a thickness of 700 μm.

In this embodiment, since the 1 st layer 20C is formed of a resist material, the surface of the 1 st layer 20C can be formed very smoothly, and the substrate for forming the 2 nd layer 30C described later is preferable. In addition, since an alignment mark (not shown) at the time of forming the layer 2 can be formed on the outer peripheral portion of the layer 1, dimensional accuracy can be improved.

The layer thickness of the 1 st layer 20C (in the case of white) is preferably 3 μm or more and 100 μm or less. This is because, if the layer thickness of the 1 st layer 20C is smaller than 3 μm, the diffuse reflectance becomes insufficient, the contrast becomes low, and the visibility of the mark 2 (detection easiness by automatic recognition) becomes low. If the layer thickness of the 1 st layer 20C is thicker than 100 μm, it is difficult to make the film thickness uniform.

In the present embodiment, the layer thickness of the 1 st layer 20C is 15 μm.

The 2 nd layer 30C is formed of a resist material colored black (2 nd color).

The 2 nd layer 30C is provided with 4 portions where the 1 st layer 20C is masked by performing partial film formation by photolithography processing described later. The region of the 2 nd layer 30C is configured to be observable as a mark 2 of an independent shape.

The layer thickness of the 2 nd layer 30C is preferably 1 μm or more and 5 μm or less. This is because the layer thickness of the 2 nd layer 30C is not uniformly formed at 1 μm or less, and the curing reactivity of the resin by ultraviolet rays is insufficient at 5 μm or more.

In embodiment 3, since the 2 nd layer 30C is black, the hiding power of the substrate is high. Therefore, the white color of the 1 st layer 20C can be sufficiently shielded without thickening the 2 nd layer 30C, and thus the thickness of the layer can be made thin as described above. Further, by forming the 2 nd layer 30C thin, a decrease in measurement accuracy due to observation of the end face of the 2 nd layer 30C can be suppressed, and measurement accuracy can be improved.

In this embodiment, the layer thickness of the 2 nd layer 30C is 1 μm.

In the mark 1C of the present embodiment, the intermediate layer 92 is laminated between the 1 st layer 20C and the 2 nd layer 30C. The intermediate layer 92 is provided to eliminate the case where the bonding force between the 1 st layer 20C and the 2 nd layer 30C cannot be sufficiently obtained. When the 2 nd layer 30C is directly laminated on the 1 st layer 20C, the 2 nd layer 30C may be repelled by the 1 st layer 20C, and in such a case, the 2 nd layer 30C can be properly laminated by providing the intermediate layer 92 which is hard to repel. Therefore, the intermediate layer 92 may be provided as needed, and may be omitted as in embodiment 1.

The intermediate layer 92 may be formed of, for example, an acrylic resin or the like, and the thickness of the layer may be about 1 μm to 2 μm, and in the present embodiment, the acrylic resin is formed at 2 μm.

Due to the relationship in which the 1 st layer 20 or 20C is laminated on the base material layer 10 and the 2 nd layer 30 or 30C is further laminated thereon, a step difference is generated at the 2 nd layer 30 or 30C after being patterned. In the case of layer 2 30 of embodiment 1, the cross-sectional shape of the portion corresponding to symbol 2 is concave, and in the case of layer 2 30C of embodiment 3, the cross-sectional shape of the portion corresponding to symbol 2 is convex.

Therefore, in the case of attaching the protective layer 70 described later, the step is buried by the adhesive layer 60 to some extent, but if the step is large, the step cannot be buried by the adhesive layer, and there is a possibility that the air layer (void) enters the vicinity of the step. Since the refractive index of the air layer is 1, which is significantly lower than the refractive index of the base material or the like of 1.4 to 1.6, reflection of light occurs at the interface between the substances, and the light becomes disturbance light when the mark 2 is detected by the camera, and the detection accuracy is significantly lowered. Therefore, in order to suppress the derivation of the air layer, the film thickness of the 2 nd layers 30, 30C is preferably 5 μm or less, more preferably 3 μm or less, and still more preferably 2 μm or less.

However, as in embodiment 1 described above, when the 2 nd layer 30 is made white, the coverage to the substrate is better than that of the black color difference, and therefore, there is a possibility that it is not desirable to make it thin, and the step difference may become large.

Therefore, when the step difference is not more than 5 μm, the planarizing layer 91 can be provided in the region around the 2 nd layers 30 and 30C and in the region where the 2 nd layers 30 and 30C are not provided, so that the air layer does not enter. The planarization layer 91 is preferably formed of a transparent material capable of identifying the mark 2, and known materials such as an acrylic material and an epoxy material can be used.

In embodiment 3, a configuration in which the planarizing layer 91 is provided to reduce the step is illustrated. By providing the planarizing layer 91, the step difference between the 2 nd layer 30C and the planarizing layer 91 can be further reduced. In embodiment 3, the 2 nd layer 30C is black, has high hiding power, and can be formed thin, so that the planarizing layer 91 can be omitted.

The protective layer 70C is a layer for protecting the 1 st layer 20C and the 2 nd layer 30C, and is adhered to the 2 nd layer 30C and the planarization layer 91 via the adhesive layer 60. In embodiment 3, an example in which the protective layer 70C is formed in a single layer is illustrated, and specifically, a matting film having a haze value of 75 and formed of a vinyl chloride resin to be 70 μm is used.

Next, a method for producing the marker 1C according to the present embodiment will be described.

Fig. 9 is a diagram showing a manufacturing process of the mark 1C. Fig. 9 shows the reverse direction (up and down) as opposed to fig. 8.

First, a glass plate is prepared as the base material layer 10 ((a) of fig. 9).

Next, a white colored resist material (layer 1 forming step) as a raw material of layer 1 20 is coated on one surface of the base layer 10, and is prebaked and dried, and then exposed to light by a light source LS (development step 1), and further developed and post-baked (baking step 1), so that layer 1 20C is stabilized (fig. 9 (b)).

Next, an intermediate layer 92 is formed on the 1 st layer 20C, and a black colored resist material is further applied thereon as a material of the 2 nd layer 30C (2 nd layer forming step), and the resultant is prebaked and dried (fig. 9 (C)).

Next, the mask M is brought into close contact with the dried layer 2 30C to expose the mark pattern on the layer 2 30C (the 2 nd exposure step) (fig. 9 (d)). A mask pattern is formed in advance on the mask M, and the mask pattern transmits light at a position corresponding to the mark 2, and blocks light at other positions.

Next, the exposed 2 nd layer 30C is developed to remove the resist material except for the portion corresponding to the mark 2 (the periphery of the mark 2), thereby forming an opening 30a (2 nd development step) (fig. 9 (e)). After development, the 2 nd layer 30C is post-baked (2 nd baking step). Further, the planarizing layer 91 is provided in a region where the 2 nd layer 30C is not formed (a region where the resist material is removed).

Finally, a film-like or sheet-like protective layer 70 prepared separately is adhered to the 2 nd layer 30C and the planarizing layer 91 via the adhesive layer 60, and the marking 1C is completed ((f) of fig. 9).

Fig. 10 is a diagram showing the multi-surface tag arrangement 100.

In the production of the marks 1C described in fig. 9, a plurality of marks 1C are arranged in an array, that is, a multi-surface mark array 100 with a plurality of marks 1C is produced. Then, each of the marks 1C is cut out from the multi-sided mark array 100 and singulated, thereby obtaining the mark 1C.

In the above-described manufacturing process, since a resist material is used and an exposure process is used, manufacturing with extremely high precision can be realized. That is, the outer shape of the marks 2 in the 1-multifaceted mark array 100 and the dimensional deviation of the arrangement pitch of the marks 2 in the respective marks 1C may be set to ±10 μm or less. More specifically, in the present embodiment, the dimensional deviation between the outer shape of the marks 2 in the 1-multifaceted mark array 100 and the arrangement pitch of the marks 2 in each mark 1C is ±1 μm or less. In the present embodiment, the outer shape of the mark 2 refers to the diameter of the mark 2, and the arrangement pitch of the marks 2 in each mark 1C refers to Px and Py shown in fig. 10.

As described above, according to embodiment 3, the 2 nd layer 30C provided on the observation side is black, and the 1 st layer 20C is white. As a result, the hiding power of the 2 nd layer 30C against the substrate becomes high, and therefore the layer thickness of the 2 nd layer 30C can be made thinner than that of embodiment 1. Therefore, when the mark 2 formed of the 2 nd layer 30C is observed, the influence on the measurement accuracy due to the observation of the side end surface of the 2 nd layer 30C can be reduced as much as possible, and measurement with higher accuracy can be realized.

Further, according to embodiment 3, by providing the planarizing layer 91, occurrence of voids due to lamination of the adhesive layer 60 can be suppressed, and a decrease in measurement accuracy can be suppressed.

In the marks 1, 1B, and 1C of embodiment 1 to embodiment 3 described above, the protective layers 70 and 70C are laminated with the adhesive layer 60 interposed therebetween. With this structure, the marks 1, 1B, 1C have very high reliability. For example, in the case where a certain object collides with the markers 1, 1B, 1C or the like in use, since the base material layer 10 is a glass plate, it is conceivable that: the substrate layer 10 may crack. However, since the protective layers 70, 70C are laminated via the adhesive layer 60, the protective layers 70, 70C function as a scattering prevention layer, and scattering of fragments of the base material layer 10 can be prevented. In addition, even when a crack occurs in the base material layer 10, the 1 st layer 20, 20C and the 2 nd layer 30, 30C are not damaged, and the function as a mark can be maintained.

This is presumed to be: since the bonding force of the 1 st layer 20, 20C and the 2 nd layer 30, 30C with respect to the base material layer 10 is weaker than the bonding force with respect to the adhesive layer 60, damage is avoided by making the 1 st layer 20, 20C and the 2 nd layer 30, 30C follow the adhesive layer 60. Therefore, the bonding force of the 1 st layer 20, 20C and the 2 nd layer 30, 30C to the base material layer 10 is preferably weaker than the bonding force of the 1 st layer 20, 20C and the 2 nd layer 30, 30C to the adhesive layer 60. It was confirmed by a drop test of the object that even if the base material layer 10 was cracked, the 1 st layer 20, 20C and the 2 nd layer 30, 30C were not damaged.

As described above, no crack is observed in the base material layer 10, either when a crack is generated in the base material layer 10 or when the crack is observed from the observation side. Therefore, a sensor for detecting damage may be provided on the back side of the base material layer 10.

The electrode layer 95 can be formed on substantially the entire back side of the base material layer 10, and can function as a sensor for detecting damage. The electrode layer 95 may be, for example, ITO, copper foil, aluminum foil, or the like, but it is necessary that damage occurs together with the base material layer 10 when the base material layer 10 is damaged. If the electrode layer 95 is damaged and the resistance value is changed, the damage of the base material layer 10 can be detected by electrically monitoring the same.

Further, by forming the electrode layer 95 from a material such as a metal having high light reflectivity, external light or detection light can be reflected by the electrode layer 95, and the visibility of the mark 2 in a dark place can be improved.

In addition, in the case where the electrode layer 95 is provided, the protective layer 70C may be omitted.

(embodiment 4)

Fig. 17 is a diagram showing embodiment 4 of the mark of the present invention.

The drawings shown below are schematic drawings, including fig. 17, and the size and shape of each part are exaggerated or omitted as appropriate for easy understanding.

As shown in fig. 17, the mark 1 is formed in a substantially square plate shape when viewed from the normal direction of the front surface provided with a protective layer 70 described later, and includes a mark 2 and moire display areas 3 and 4. In the present embodiment, the shape as viewed from the front side is formed in a square shape of 60mm×60 mm. The mark 1 detects the relative positional relationship between the imaging position and the mark 1 (hereinafter, also simply referred to as position detection) based on how the mark 2 is observed, and further, can detect the position with higher accuracy based on how moire displayed in the moire display regions 3 and 4 is observed. In addition, with regard to the mark 1, the surface shown in fig. 17 is the front side (front surface) to be observed, the opposite side thereof is the back side (back surface), and in fig. 18 described later, the side on which the protective layer 70 is provided is the front side (front surface) to be observed.

The marks 2 are arranged at two positions near the upper two corners in fig. 17, and at one position near the lower left and right centers, and a total of 3 marks are arranged at intervals. The symbol 2 is configured to be observable as a symbol of an independent shape. The symbol having an independent shape means that a plurality of symbols are not connected to each other but are individually identifiable.

Preferably at least 3 markings 2 are provided. This is because, for example, if the position of the center of gravity of the 3-point mark 2 is calculated from the observation result of the mark 2, the relative position and the slope between the observation position (camera or the like) and the mark 1 can be accurately detected. If the number of marks 2 is greater than 3, for example, if some marks 2 are not clearly observed due to some obstacle, position detection can be performed based on the observation results of the remaining marks 2. In addition, by using a plurality of marks 2, the accuracy of position detection can be improved.

In the present embodiment, the symbol 2 is formed in a circular shape, but the shape is not limited to a circular shape, and may be a polygonal shape such as a triangle or a quadrangle, or may be other shapes.

The moire display regions 3, 4 display moire patterns M. Fig. 17 shows a state in which the moire M is displayed in the center of the moire display regions 3, 4 in both the moire display regions 3, 4. The position where the moire M is displayed moves when the relative position (angle) of the mark 1 and the observation position changes. In the present embodiment, the length of each of the moire display regions 3 and 4 in the longitudinal direction is 30mm, and the position of the moire M displayed in the longitudinal direction is shifted. The moire display region 3 and the moire display region 4 are arranged so that the longitudinal directions thereof are orthogonal. Since the display regions 3 and 4 have the same configuration except for the arrangement direction, the display region 3 will be described in the following description.

The mark 1 includes a base material layer 10, a 1 st layer 20, a 2 nd layer 30, a 3 rd layer 40, a reflective layer 50, an adhesive layer 60, and a protective layer 70, and is formed in a thin plate shape. The order of lamination of these layers is the order of the reflective layer 50, the 3 rd layer 40, the base material layer 10, the 1 st layer 20, the 2 nd layer 30, the adhesive layer 60, and the protective layer 70 from the back surface side.

The measurement of the linear expansion coefficient of the glass plate used as the base material layer 10 was performed in accordance with JIS R3102.

The linear expansion coefficient of the ceramic is, for example, 28×10 ^-7 about/DEG C, the dimensional change due to the temperature change is very small as in glass. Therefore, ceramics may also be used for the substrate layer. In order to suppress dimensional change due to temperature change, the linear expansion coefficient of the base material layer 10 is preferably 35×10 ^-6 at/DEG CAnd (3) downwards.

The thickness of the base material layer 10 is preferably 0.3mm or more and 2.3mm or less. This is because if the layer thickness of the base material layer 10 is less than 0.3mm, the base material layer will break during the cutting process, and therefore additional processing will not be performed, and if it is thicker than 2.3mm, the weight will be too large to be transported. The thickness of the base material layer 10 of the present embodiment was 0.7mm.

The 1 st layer 20 is formed of a resist material colored black (1 st color). The resist material constituting the 1 st layer 20 of the present embodiment is: as a result of developing a resist material having photosensitivity used in a photolithography process, the resist material is in a state after photosensitivity is lost. As a resist material used for the 1 st layer 20 (in the case of black), PMMA, ETA, HETA, HEMA or a mixture with an epoxy resin is exemplified. Examples of the material to be colored black include carbon, titanium black, and nickel oxide.

In this embodiment, since the 1 st layer 20 is formed of a resist material, the surface of the 1 st layer 20 can be formed very smoothly, and it is preferable as a substrate for forming the 2 nd layer 30 described later. Further, since the 1 st layer 20 is formed of a resist material, the 1 st pattern 23 described below can be manufactured with high accuracy and in a simple manner.

The layer thickness of the 1 st layer 20 (in the case of black) is preferably 1 μm or more and 5 μm or less. This is because the layer thickness of the 1 st layer 20 is not uniformly formed at 1 μm or less, and the curing reactivity of the resin by ultraviolet rays is insufficient at a thickness of more than 5 μm.

Layer 1, 20, constitutes the black-appearing portion of the symbol 2. The 1 st layer 20 forms a 1 st pattern 23 for displaying moire in the moire display region 3. The 1 st pattern 23 is arranged on one surface (front surface) of the base material layer 10 in a region to be the moire display region 3.

In the 1 st pattern 23, the 1 st display lines 21 are arranged at equal intervals along a certain arrangement direction in the longitudinal direction of the moire display region 3. The 1 st non-display area 22 is a portion between the adjacent 1 st display lines 21 where the 1 st display line 21 is not provided, and the 1 st display lines 21 and the 1 st non-display area 22 are alternately arranged. The 1 st pattern 23 is formed by a photolithography process.

Layer 2 30 is formed of a resist material colored white (color 2). The resist material constituting the layer 2 30 of the present embodiment is: as a result of developing a resist material having photosensitivity used in a photolithography process, the resist material is in a state after photosensitivity is lost. As a resist material used for the 2 nd layer 30 (in the case of white), PMMA, ETA, HETA, HEMA or a mixture with an epoxy resin is exemplified. Examples of the material colored in white include titanium oxide, zirconium oxide, and barium titanate.

The 2 nd layer 30 is provided with an opening 31 for visualizing the 1 st layer 20 by opening the position of the mark 2 at 3 positions, and is provided with an opening 32 for visualizing the 1 st layer 20 and the 3 rd layer 40 by opening the position of the moire display regions 3 and 4 at 2 positions. These openings 31 and 32 are formed by photolithography.

The layer thickness of the 2 nd layer 30 is preferably 3 μm or more and 100 μm or less. This is because, if the layer thickness of the 2 nd layer 30 is smaller than 3 μm, the 1 st layer 20 of the substrate is observed through the 2 nd layer 30, and the contrast is lowered, and the visibility of the mark 2 (the ease of detection by automatic recognition) is lowered. If the layer thickness of the 2 nd layer 30 is thicker than 100 μm, when the mark 2 is observed from an oblique direction, the region where the 1 st layer 20 is not seen is increased by the shadow of the 2 nd layer 30 at the peripheral edge of the opening 31, and the deformation of the shape of the observed mark 2 is increased.

Layer 3 40 is formed of a resist material that is colored black (color 1). The 3 rd layer 40 of the present embodiment is made of the same material as the 1 st layer 20, and its preferable film thickness is also the same as the 1 st layer 20. Since the 3 rd layer 40 is formed of a resist material, the 2 nd pattern 43 described below can be manufactured with high accuracy and in a simple manner.

The 3 rd layer 40 is provided with a 2 nd pattern 43 for displaying moire in the moire display region 3. The 2 nd pattern 43 is disposed opposite to the 1 st pattern 23 in a region serving as the moire display region 3 on the back surface of the base material layer 10. In the present embodiment, the 1 st pattern 23 is provided on one surface of the base material layer 10, and the 2 nd pattern 43 is provided on the other surface, but the present invention may be configured so that: they are formed by being attached to other substrates, etc., after being separately provided.

In the 2 nd pattern 43, the 2 nd display lines 41 are arranged at equal intervals in a certain arrangement direction in the longitudinal direction of the moire display region 3. The portion between the adjacent 2 nd display lines 41 where the 2 nd display line 41 is not provided is the 2 nd non-display region 42, and the 2 nd display lines 41 and the 2 nd non-display regions 42 are alternately arranged. The 2 nd pattern 43 is formed by a photolithography process.

The reflective layer 50 reflects light reaching from the front side (observation side) of the mark 1 through the opening 32 toward the front side. The reflective layer 50 may be formed using PMMA, ETA, HETA, HEMA, a mixture with an epoxy resin, or the like, and is preferably white in order to improve contrast with the 1 st display line 21 and the 2 nd display line 41. Examples of the material colored in white include titanium oxide, zirconium oxide, and barium titanate.

Here, the reflective layer 50 may be a reflective member or the like formed by disposing another member on the rear surface side of the marker 1, in addition to the structure in which the reflective layer is laminated so as to be integrally with the marker 1 as in the present embodiment. However, the structure of the present embodiment in which the reflective layer 50 is laminated so as to be integral with the mark 1 is more preferable in that moire M can be made particularly easily visible. The reason for this will be described below.

The moire M that is originally intended to be observed is a moire observed by interference between the 1 st display line 21 and the 2 nd display line 41. However, even if only the 1 st display line 21 and only the 2 nd display line 41 are used, unwanted moire (excessive noise image) is generated depending on conditions.

Fig. 19 is a view in which the vicinity of the 2 nd pattern 43 is enlarged to explain the cause of unwanted moire generation. Fig. 19 (a) shows a structure in which the reflection layer 50 is laminated so as to bury the 2 nd non-display region 42. Fig. 19 (b) shows a structure in which the reflection layer 50 is laminated so as not to bury the 2 nd non-display region 42. Fig. 19 (c) shows a structure in which the reflection layer 50 is laminated via a bonding layer 51 such as an adhesive layer. As in the case of the modes (b) and (c) of fig. 19, when the 2 nd non-display region 42 is not buried by the reflective layer 50, the light L1 incident from the observation side is reflected by the end portion or the like of the 2 nd display line 41, and the unnecessary light L3 and L4 returned to the observation side are generated. Since such unnecessary light L3 and L4 is also periodically generated, it is considered that unnecessary moire is generated. On the other hand, in the structure in which the reflective layer 50 is laminated so as to cover the 2 nd non-display region 42 as in fig. 19 (a), since the light cannot reach the end portion or the like of the 2 nd display line 41, the normal reflected light L2 returns to the observation side, and the occurrence of unnecessary moire can be suppressed, and clear moire can be observed.

In this way, when unnecessary moire of the 2 nd display line 41 is generated by light that is scattered and returned to the observer side at the side surface portion of the 2 nd display line 41, that is, at the end surface portion of the 2 nd display line 41 existing on the 2 nd non-display area 42 side, it is conceivable that it interferes with the moire M that is originally desired to be seen, and becomes an obstacle to observing the moire M. Therefore, by designing the reflective layer 50 so as to bury the 2 nd non-display region 42, the above phenomenon can be avoided, and the moire M can be more clearly observed.

For the above reasons, the reflective layer 50 may be provided at least in the 2 nd non-display region 42, but is preferably provided so as to cover the back surface side of the 2 nd display line 41 as shown in fig. 18. The reason for this is that: the bounce of light from the edge portion on the back surface side of the 2 nd display line 41 is suppressed, and the main component of the bounce light having periodicity disappears.

The thickness of the adhesive layer 60 is preferably 0.5 μm or more and 50 μm or less. This is because, if the layer thickness of the adhesive layer 60 is less than 0.5 μm, it is difficult to uniformly process, and the irregularities of the substrate cannot be absorbed. In addition, if the layer thickness of the adhesive layer 60 is thicker than 50 μm, the solvent removal at the time of thick coating process takes much effort and the cost becomes high.

The protective layer 70 is a layer for protecting the 1 st layer 20 and the 2 nd layer 30, and is adhered to the 2 nd layer 30 via the adhesive layer 60. The protective layer 70 has a resin base layer 71 and a front layer 72.

The resin base layer 71 has the adhesive layer 60 laminated on one surface and the front layer 72 laminated on the other surface. The resin base layer 71 is made of a transparent resin so that the 1 st layer 20 and the 2 nd layer 30 can be observed.

In the present embodiment, it is assumed that the adhesive layer 60 and the resin base layer 71 are configured to be transparent to white light by the mark 1 under visible light. Specifically, it is preferable that the total light transmittance of the adhesive layer 60 and the resin base layer 71 is 50% or more in the region where the wavelength of light is 400nm to 700nm, respectively. More preferably, the total light transmittance in the region where the wavelength of light is 400nm to 700nm is 50% or more in a state where the adhesive layer 60 and the resin base material layer 71 are measured together.

The front surface layer 72 is a layer having both an antireflection function and a hard coat function. In order to prevent the visibility of the mark 2 and the moire display regions 3, 4 from being reduced by reflection on the front surface of the mark 1, it is preferable that the front surface layer 72 has a reflectance of 1.5% or less for light having a wavelength of 535 nm. The hard coat function of the front surface layer 72 is preferably 1H or more in terms of pencil hardness.

The 1 st non-display region 22 described above is filled with the adhesive layer 60, but the adhesive layer 60 and the protective layer 70 are transparent, and the base material layer 10 is also made of glass and transparent, so that the 2 nd pattern 43 of the 3 rd layer 40 can be seen through the 1 st non-display region 22. Therefore, when the mark 1 is viewed from the front side, the 1 st pattern 23 and the 2 nd pattern 43 are viewed in a superimposed state, and moire M can be observed.

The total light transmittance is preferably 85% or more as a characteristic of combining the adhesive layer 60 and the protective layer 70. If the total light transmittance is less than 85%, a sufficient amount of light cannot be ensured.

Further, as a characteristic of combining the adhesive layer 60 and the light diffusion layer 70, a haze value of 30% or more, more preferably 40% or more, and still more preferably 70% or more is desirable. This is because, if the haze value is less than 70%, the effect of the present invention starts to decrease, and if it is 40% or less, it is further decreased, and if it is 30% or less, it is significantly decreased. On the other hand, the haze value is preferably 95% or less. This is because, if the haze value is higher than 95%, the image of the observed mark becomes blurred.

Conventionally, as described in patent document 1 (U.S. Pat. No. 8625107), when moire fringes are generated by overlapping a plurality of patterns, light is blocked by the patterns disposed on the observation side, and the entire appearance is dark. Even if moire fringes are generated in the process of being dark as a whole, the moire fringes are not clear, and it is sometimes difficult to take a picture of the moire fringes with a camera and determine the positions of the moire fringes. Therefore, in the present embodiment, moire can be more clearly observed by modifying the 1 st pattern 23 and the 2 nd pattern 43.

Fig. 20 is a diagram illustrating details of the 1 st pattern 23 and the 2 nd pattern 43. Fig. 20 shows the same cross section as fig. 18, but shows only 3 layers of the base material layer 10, the 1 st layer 20, and the 3 rd layer 40.

In the present embodiment, the width of the 1 st non-display area 22 is different from the width of the 2 nd non-display area 42. Specifically, in the present embodiment, the width of the 1 st non-display area 22 is set to 0.64mm, and the width of the 2 nd non-display area 42 is set to 0.1mm. Since the 1 st non-display region 22 is disposed on the observation side (front side), the 1 st non-display region 22 has a wider width than the 2 nd non-display region 42, and thus the light passes through the 1 st pattern 23 to reach the 2 nd pattern 43 in a large amount, and most of the light reflected and returned to the observation side can pass through the 1 st pattern 23 to reach the observation position. Therefore, the moire M can be more brightly observed.

In addition, the width of the 1 st display line 21 is different from the width of the 2 nd display line 41. As a result, moire M can be more clearly observed than in the case where the widths of both are the same. Specifically, the width of the 1 st display line 21 is set to 0.1mm, and the width of the 2 nd display line is set to 0.4mm. By making the width of the 1 st display line 21 smaller than the width of the 2 nd display line in this way, the light passing through the 1 st pattern 23 becomes more, and the moire M can be more brightly observed.

The 1 st pitch, which is the pitch at which the 1 st display lines 21 are arranged, was set to 0.74mm, and the 2 nd pitch, which is the pitch at which the 2 nd display lines 41 are arranged, was set to 0.5mm, so that the two pitches were different. Thus, moire M can be more clearly observed. Further, since the 1 st pitch is set to be wider than the 2 nd pitch, as a result, the 1 st non-display region 22 is wider than the 2 nd non-display region 42, and moire M can be more brightly observed.

Next, an example of a method of using the marker 1 of the present embodiment will be described.

Fig. 21 is a diagram showing a state in which the marker 1 is viewed from an oblique direction. Fig. 21 illustrates such a state: the mark 1 is observed from an oblique direction indicated by an arrow B in fig. 18, but is not obliquely observed in the up-down direction in fig. 17.

When the mark 1 is observed from an oblique direction oblique to the normal direction of the mark 1, for example, as shown in fig. 21, the moire M of the moire display region 3 is moved in the longitudinal direction of the moire display region 3 and is observed. Further, if the mark 1 is observed from the vertical oblique direction oblique from the normal direction of the mark 1 to the longitudinal direction of the moire display area 4, the moire M of the moire display area 4 is moved in the longitudinal direction of the moire display area 4 and is observed. Therefore, by observing both the moire M of the moire display region 3 and the moire M of the moire display region 4, the relative position (angle of inclination) of the mark 1 and the observation position can be accurately detected. That is, the marker 1 can be used in combination with the imaging unit and the computing unit to form a part of the angle sensor.

Here, when the observation position is moved to a position greatly shifted from the normal direction of the mark 1, another moire pattern is observed, and the moire patterns are observed in sequence. Therefore, when the observation position is located at a position greatly deviated from the normal direction of the mark 1, accurate position detection may not be performed.

However, the mark 1 of the present embodiment is provided with a mark 2. In the position detection by the mark 2, even if the observation position is a position greatly deviated from the normal direction of the mark 1, the position detection can be performed. On the other hand, the position detection using the moire display regions 3 and 4 can be performed with higher accuracy than the position detection based on the mark 2. Therefore, by using both the position detection using the mark 2 and the position detection using the moire display regions 3 and 4, the application range can be enlarged as compared with the case where only the moire display regions 3 and 4 are used. That is, even if the observation position is greatly deviated from the normal direction of the mark 1, the position detection can be performed by the mark 2, and the observation position is automatically moved based on the detection result, and the position detection using the moire display areas 3 and 4 is performed at a stage where the final high-precision position control is required.

As described above, according to the mark 1 of the present embodiment, since the 1 st non-display region 22 has a wider width than the 2 nd non-display region 42, more light can be introduced into the moire display regions 3 and 4, and more light can be returned to the observation side, so that the moire M can be displayed more brightly. Therefore, even if the moire pattern M displayed in the moire pattern display regions 3 and 4 is photographed by a camera or the like, the position thereof can be acquired more accurately, and thus highly accurate position detection can be realized.

(embodiment 5)

Fig. 22 is a diagram showing embodiment 5 of the mark of the present invention.

The drawings shown below are schematic drawings including fig. 22, and the size and shape of each part are exaggerated or omitted as appropriate for easy understanding.

In the following description, specific numerical values, shapes, materials, and the like are shown and described, but these can be appropriately changed.

As shown in fig. 22, the mark 1 is formed in a substantially square plate shape when viewed from the normal direction of the front surface provided with a light diffusion layer 80 described later, and includes a mark 2 and moire display areas 3 and 4. In the present embodiment, the shape as viewed from the front side is formed in a square shape of 60mm×60 mm. The mark 1 detects the relative positional relationship between the imaging position and the mark 1 (hereinafter, also simply referred to as position detection) based on how the mark 2 is observed, and further, can detect the position with higher accuracy based on how moire displayed in the moire display regions 3 and 4 is observed. Note that, with reference numeral 1, the surface shown in fig. 22 is the front side (front surface) to be observed, the opposite side is the back side (back surface), and in fig. 23 described later, the side on which the light diffusion layer 80 is provided is the front side (front surface) to be observed.

The marks 2 are arranged at two positions near the upper two corners in fig. 22, and at one position near the lower left and right centers, and a total of 3 marks are arranged at intervals. The symbol 2 is configured to be observable as a symbol of an independent shape. The symbol having an independent shape means that a plurality of symbols are not connected to each other but are individually identifiable.

The moire display regions 3, 4 display moire patterns M. Fig. 22 shows a state in which moire M is displayed in the center of the moire display regions 3, 4 in both the moire display regions 3, 4. The position where the moire M is displayed moves when the relative position (angle) of the mark 1 and the observation position changes. In the present embodiment, the length of each of the moire display regions 3 and 4 in the longitudinal direction is 30mm, and the position of the moire M displayed in the longitudinal direction is shifted. The moire display region 3 and the moire display region 4 are arranged so that the longitudinal directions thereof are orthogonal. Since the moire display regions 3 and 4 have the same configuration except that the arrangement direction is different, the moire display region 3 will be described in the following description.

The mark 1 includes a base material layer 10, a 1 st layer 20, a 2 nd layer 30, a 3 rd layer 40, a reflective layer 50, an adhesive layer 60, and a light diffusion layer 80, and is formed in a thin plate shape. The order in which these layers are stacked is: the reflective layer 50, the 3 rd layer 40, the base material layer 10, the 1 st layer 20, the 2 nd layer 30, the adhesive layer 60, and the light diffusion layer 80 are in this order from the back surface side.

The linear expansion coefficient of the ceramic is, for example, 28×10 ^-7 about/DEG C, the dimensional change due to the temperature change is very small as in glass. Therefore, ceramics may also be used for the substrate layer. In order to suppress dimensional change due to temperature change, the linear expansion coefficient of the base material layer 10 is preferably 35×10 ^-6 And/or lower.

The 1 st layer 20 is formed of a resist material colored black (1 st color). The resist material constituting the 1 st layer 20 of the present embodiment is: as a result of developing a resist material having photosensitivity used in a photolithography process, the resist material is in a state after photosensitivity is lost. As a resist material used for the 1 st layer 20 (in the case of black), PMMA (polymethyl methacrylate), ETA (eicosatetraenoic acid), HETA (hydroxyeicosatetraenoic acid), HEMA (2-hydroxyethyl methacrylate), or a mixture with an epoxy resin can be exemplified. Examples of the material to be colored black include carbon, titanium black, and nickel oxide.

The moire M that is originally intended to be observed is a moire observed by interference between the 1 st display line 21 and the 2 nd display line 41. However, even if only the 1 st display line 21 and only the 2 nd display line 41 are used, unwanted moire (excessive noise image) is generated depending on conditions. When unwanted moire of the 2 nd display line 41 is generated by light that is scattered and returned to the observer side at the side surface portion of the 2 nd display line 41, that is, at the end surface portion of the 2 nd display line 41 existing on the 2 nd non-display area 42 side, it is conceivable that it interferes with the moire M that is originally desired to be seen, and becomes an obstacle to observing the moire M. Therefore, by designing the reflective layer 50 so as to bury the 2 nd non-display region 42, the above phenomenon can be avoided, and the moire M can be more clearly observed.

For the above reasons, the reflective layer 50 may be provided at least in the 2 nd non-display region 42, but is preferably provided so as to cover the back surface side of the 2 nd display line 41 as shown in fig. 23. The reason for this is that: the bounce of light from the edge portion on the back surface side of the 2 nd display line 41 is suppressed, and the main component of the bounce light having periodicity disappears.

The adhesive layer 60 is a layer of adhesive for adhering the light diffusion layer 80 to the 2 nd layer 30. The adhesive layer 60 is formed of, for example, PMMA, polyurethane, silicone, or the like.

The adhesive layer 60 is provided only in the same range as the range in which the light diffusion layer 80 is provided.

The light diffusion layer 80 covers the mark 2 and the moire display areas 3 and 4 via the adhesive layer 60, and is provided in an island shape in a slightly larger range than these. Specifically, the light diffusion layer 80 is provided in an island shape in a range of 2 to 3mm larger than the mark 2 on one side (radius). Similarly, the light diffusion layer 80 is provided in an island shape in a range of 2 to 3mm larger than the moire display regions 3 and 4 on one side (the width of the expansion on one side).

By providing the light diffusion layer 80 in an island shape and not providing the light diffusion layer 80 at other portions, the light diffusion layer can be easily provided later as needed. In addition, the following can be prevented: when strong light such as solar rays is incident on only one island-shaped light diffusion layer 80, if the light diffusion layers 80 (including the resin base material layer 81) are connected, the resin base material layer 81 becomes a light guide plate and propagates to the other island-shaped light diffusion layers 80, and thus affects the other islands.

The light diffusion layer 80 has a resin base material layer 81 and a front surface layer 82.

The resin base layer 81 is laminated with the adhesive layer 60 on one side and the front layer 82 on the other side. The resin base layer 81 is composed of a transparent resin so that the 1 st layer 20 and the 2 nd layer 30 can be observed.

In the present embodiment, it is assumed that the adhesive layer 60 and the resin base layer 81 are configured to be transparent to white light by the mark 1 under visible light. Specifically, it is preferable that the total light transmittance of the adhesive layer 60 and the resin base material layer 81 is 50% or more in the region where the wavelength of light is 400nm to 700nm, respectively. More preferably, the total light transmittance in the region where the wavelength of light is 400nm to 700nm is 50% or more in a state where the adhesive layer 60 and the resin base material layer 81 are measured together.

The layer thickness of the resin base layer 81 is preferably 7 μm or more and 250 μm or less. This is because, if the layer thickness of the resin base layer 81 is less than 7 μm, it is difficult to perform lamination processing. In addition, if the layer thickness of the resin base layer 81 is thicker than 250 μm, the volume and weight become excessively large, and the cost becomes high.

The refractive index of the resin base layer 81 is preferably 1.45 or more and 1.55 or less.

The front layer 82 is a layer that plays a role of light diffusion. The front layer 82 of the present embodiment has a fine uneven shape on the surface, and constitutes a so-called rough surface (rough surface). The front surface layer 82 diffuses the surface reflected light by the fine uneven shape.

The front layer 82 having such fine irregularities may be applied to various antireflection layers suitable for antiglare films. For example, the front surface layer 82 may be produced by embossing, may be produced by mixing light-transmitting fine particles to form a roughened surface, may be produced by dissolving a surface with a drug to form a roughened surface (so-called chemical roughened surface), or may be produced by a shaping treatment using a shaping resin layer.

In addition, the front surface layer 82 has a hard coat function. The hard coat function of the front surface layer 82 is preferably 1H or more in terms of pencil hardness. By providing the front surface layer 82 with a hard coat function, the light diffusion layer 80 can also have a function as a protective layer.

In order to prevent the visibility of the mark 2 and the moire display regions 3 and 4 from being reduced by reflection on the front surface of the mark 1, it is preferable that the regular reflectance of the front surface layer 82 with respect to light having a wavelength of 535nm is 1.5% or less.

Further, as a characteristic of combining the adhesive layer 60 and the light diffusion layer 80, it is preferable that the total light transmittance is 85% or more. If the total light transmittance is less than 85%, a sufficient amount of light cannot be ensured.

Further, as a characteristic of combining the adhesive layer 60 and the light diffusion layer 80, a haze value of 30% or more, more preferably 40% or more, and still more preferably 70% or more is desirable. This is because, if the haze value is less than 70%, the effect of the present invention starts to decrease, and if it is 40% or less, it is further decreased, and if it is 30% or less, it is significantly decreased. On the other hand, the haze value is preferably 95% or less. This is because, if the haze value is higher than 95%, the image of the observed mark becomes blurred.

Fig. 24 is a graph showing the effect of the light diffusion layer 80.

In order to confirm the effect of providing the light diffusion layer 80, two kinds of marks are actually made according to the presence or absence of the light diffusion layer 80. Then, the positions of the marks 2 of the two marks are irradiated with illumination light so that the reflected light is strongly returned to the camera to capture them, and the change in light intensity in the vicinity of the portion where the black and white of the marks 2 are inverted is digitized and shown in fig. 24.

As shown in fig. 24, when the light diffusion layer 80 is not provided, reflection of the illumination light is directly expressed as a waveform, and no waveform corresponding to the shape of the mark 2 is found. The light intensity without the light diffusion layer 80 was too high, exceeding the measurement limit (2.50e+02).

In contrast, when the light diffusion layer 80 is provided, data is obtained which can be identified by appropriately distinguishing the light intensity of the white portion and the light intensity of the black portion in accordance with the position of the mark 2. Further, the light diffusion layer 80 was measured by using a haze meter "HM-150" manufactured by Country color research according to JIS K7136, and as a result, the total light transmittance was 90.3%, and the haze value was 75.1%.

As can be seen from fig. 24, if the light diffusion layer is disposed so as to span the mark and its peripheral portion, the shape (outline) of the mark can be clearly captured by the camera.

When the light diffusion layer is disposed only on the mark in the same shape and size as the mark, the resin base layer of the light diffusion layer functions as a light guide plate, and thus the following problems occur: light is emitted from the end of the resin base layer, and the shape (outline) of the symbol becomes unclear.

Fig. 25 is a diagram showing a state in which the marker 1 is viewed from an oblique direction. Fig. 25 illustrates such a state: the mark 1 is observed from an oblique direction indicated by an arrow B in fig. 23, but is not obliquely observed in the up-down direction in fig. 22.

When the mark 1 is observed from an oblique direction oblique to the normal direction of the mark 1, for example, as shown in fig. 25, the moire M of the moire display region 3 is moved in the longitudinal direction of the moire display region 3 and is observed. Further, if the mark 1 is observed from the vertical oblique direction oblique from the normal direction of the mark 1 to the longitudinal direction of the moire display area 4, the moire M of the moire display area 4 is moved in the longitudinal direction of the moire display area 4 and is observed. Therefore, by observing both the moire M of the moire display region 3 and the moire M of the moire display region 4, the relative position (angle of inclination) of the mark 1 and the observation position can be accurately detected. That is, the marker 1 can be used in combination with the imaging unit and the computing unit to form a part of the angle sensor.

As described above, the relative positions of the observation position and the marker 1 are assumed to have various positional relationships. Therefore, there are also cases where: the position relationship is such that illumination light, sunlight, etc. are reflected in regular directions toward the observation position. Even in such a case, since the mark 1 of the present embodiment has the light diffusion layer 80, the reflected light can be appropriately diffused, and the conditions of the mark 2 and the moire display areas 3 and 4 in which the mark can be observed can be increased.

As described above, according to the marker 1 of the present embodiment, it is possible to improve the situation where it is difficult to recognize the index or the like shown in the marker 1 by the illumination light or the sunlight, and it is possible to provide a marker which is easy to recognize even in an environment where the sunlight or the illumination light or the like is irradiated on the marker.

(embodiment 6)

Fig. 27 is a diagram showing embodiment 6 of the mark of the present invention.

The mark 1 of embodiment 6 includes a mark 2, moire display areas 3 and 4, and an identification mark 5. The mark 1 of embodiment 6 is identical to the other embodiment described above except that the arrangement of the mark 2 and moire display regions 3 and 4 is different, and that the identification mark 5 is provided. Therefore, portions that realize the same functions as those of the above-described embodiments are given the same reference numerals, and repetitive description thereof will be omitted as appropriate. Note that, the layer structure of the mark 1 of embodiment 6 is the same as that of the mark 1 of embodiment 1, but may be configured in the same manner as that of the mark 1C of embodiment 3.

In the present embodiment, the marks 2 are provided near the 4 corners, respectively. In addition, moire display regions 3 are provided near the upper and lower end portions in fig. 27, respectively. The moire display areas 4 are provided near the left and right end portions in fig. 27, respectively. An identification mark 5 is provided at the center of the mark 1.

The identification mark 5 is a pattern (pattern for identification) in which a specific meaning is associated with a pattern of the mark and unique information is displayed by the pattern. For example, the identification mark 5 is associated with a unique number, letter, or the like for each different pattern. The identification mark 5 may be a two-dimensional bar code, a three-dimensional bar code, a QR code (registered trademark), an ArUco, or the like. As described above, various known identification codes or the like can be used for the identification mark 5, but the identification mark 5 according to the present embodiment, which is formed in a large pattern by reducing the number of patterns, can be easily detected by a camera.

The mark 1 of the present embodiment is attached to, for example, a tray P for logistics, and can be used when the tray P is identified as a detection target. Therefore, for example, based on the result of imaging by the camera of the automated forklift, the relative positional relationship between the forklift and the pallet can be accurately grasped, and the driving of the forklift can be controlled based on the relative positional relationship, and further, the pallet P can be individually identified.

In addition, as for the method of attaching the marker 1 to the detection object, for example, an adhesive or a bonding agent may be used, or an attachment shape for attaching the marker 1 to the tray P may be provided and attached thereto so as to be detachable.

According to the marker 1 of the present embodiment, since the identification mark 5 is provided, the marker can be used not only for position detection as in the other embodiment described above, but also for identification of an object to which the marker 1 is attached.

Note that, although the mark 1 having the moire display regions 3 and 4 is illustrated in fig. 27 and 28, since the purpose of the moire display region is to measure the inclination of the mark with high accuracy, the moire display region can be omitted if the measurement accuracy by the mark 2 alone is sufficient to satisfy the target accuracy.

In the case where the tag 1 is mounted on the tray P for logistics, the protective layers 70, 70C are preferably laminated with the adhesive layer 60 interposed therebetween. Even when, for example, the claws of a forklift strike the mark 1, the protective layers 70 and 70C function as scattering prevention layers, and therefore scattering of fragments of the base material layer 10 is prevented. In addition, even when a crack occurs in the base material layer 10, the 1 st layer 20, 20C and the 2 nd layer 30, 30C are not damaged, and the function as a mark can be maintained.

The measurement system 500 is not limited to the mark 1 of embodiment 6, and marks 1, 1B, 1C and the like described in embodiment 1 to embodiment 6 can be used.

The measurement system 500 includes the pallet P on which the mark 1 of embodiment 6 described above is mounted, and the forklift 200.

The forklift 200 includes a camera (imaging unit) 201, a computing unit 202, and a control unit 203.

The camera (imaging unit) 201 is provided for imaging the front of the forklift 200, and is provided for imaging the mark 1.

The calculation unit 202 calculates the relative positional relationship between the camera 201 and the marker 1 using the image of the marker 2 included in the image of the marker 1 captured by the camera 201.

The calculation method (measurement method) performed by the calculation unit 202 for calculating the size or the orientation of the mark 2 using the captured image of the mark 2 is a method described in "the basic and latest trends of AR mark technology" which is known in the field (vol.97, no.8,2014, p.734-740).

In addition, this is a technology also disclosed in the following internet URL. "Detection of ArUco Marker" [ order and 6 th 4, retrieval ], internet < URL: https:/docs. Opencv. Org/4.X/d 5/dae/tutorial_structure_detection html >. In the column "Pose Estimation" of this web page, if the center of each of the 4 tokens 2 is regarded as the coordinate vector of the four corners of the ArUco Marker, the calculation can be easily performed using the function of OpenCV (Open Source Computer Vision Library).

In the case of the present embodiment for controlling the forklift 200, the calculation unit 202 calculates (measures) the relative positional relationship between the camera 201 and the marker 1, but other calculations (measurements) may be performed. For example, the arithmetic section 202 may perform the following calculation.

Operational example 1

First, the computing unit 202 can compute the relative positional relationship between the camera 201 and the mark 2. The relative positional relationship between the camera 201 and the mark 2 includes not only the size (distance) from the camera 201 to the mark 2, but also the direction in which the front of the mark 2 (mark 1) faces, that is, the posture of the mark (posture of the mark 1 including the mark 2). Here, the posture of the symbol 2 is represented by, for example, roll, yaw, and pitch.

Operational example 2

The calculation unit 202 can calculate the size of an object or the like located in the vicinity of the marker 2. For example, the height of a person standing near the marker 1 displaying the sign 2 may be measured. The person can be identified automatically. The present invention is not limited to humans, and may be, for example, tree heights, animal sizes, or the like, or window sizes, or the like.

Operational example 3

The calculation unit 202 can calculate the size (distance) between the positions specified in the vicinity of the mark 2. The position specified in the vicinity of the symbol 2 means: a position specified by the user within a range photographed together with the mark 2 on the photographed image photographed by the camera 201.

Operational example 4

The calculation unit 202 can calculate the size (distance) between the marks 1 (marks 2) arranged in plurality. When a plurality of marks 1 are arranged, the camera 201 captures a plurality of marks 2 in one screen, whereby the size (distance) between the marks 2 arranged in plurality can be calculated. As described above, the calculation unit 202 can calculate the relative positional relationship between the camera 201 and the mark 1 (mark 2). Therefore, even if the plurality of marks 1 are respectively imaged without almost moving the position of the camera 201, the size (distance) between the plurality of marks 1 (marks 2) can be calculated. In this case, the marks 1 can be separately identified based on the unique information indicated by the identification mark 5, and thus the calculation can be accurately performed.

The control unit 203 performs control based on the calculation result of the calculation unit 202. In the present embodiment, the control performed by the control unit 203 is overall control of driving including up-and-down operations of the forks 200a of the forklift 200.

The control unit 203 has information such as the shape and size of the tray P and at which position of the tray P the mark 1 is attached. Therefore, the control unit 203 can grasp the relative positional relationship between the pallet P and the forklift 200 from the relative positional relationship between the mark 1 and the camera 201 calculated by the calculation unit 202. The control unit 203 can accurately grasp the relative positional relationship between the pallet P and the forklift 200, which are changed at the time, to accurately move the forklift 200 with respect to the pallet P as the target, and can appropriately operate the pallet fork 200 a. Here, since the identification mark 5 is provided on the mark 1, each tray P can be identified.

The arithmetic unit 202 and the control unit 203 of the present embodiment are configured by installing a computer program in a computer. More specifically, the computing unit 202 and the control unit 203 of the present embodiment are configured by installing the application program for the measurement system of the present invention in a computer for controlling the forklift 200. The computer used for controlling the forklift 200 may be a general-purpose smart phone, a tablet terminal, a notebook computer, or the like, or a special-purpose computer dedicated to controlling the forklift 200. The computer in the present invention refers to an information processing device including a control unit, a storage device, and the like.

In the present embodiment, the example in which the arithmetic unit 202 and the control unit 203 are mounted on the forklift 200 has been described, but the arithmetic unit 202 and the control unit 203 may be provided on a server or the like provided at a position distant from the forklift 200, for example. In this case, the information from the plurality of forklifts 200 can be integrated to more appropriately control the operation of each forklift 200. The computing unit 202 may be mounted on the forklift 200, and the control unit 203 may be provided on the server.

In step (hereinafter, simply referred to as S) 11, the control unit 203 starts shooting by the camera 201 and movement of the forklift 200. In this example, for simplicity, it is assumed that the control unit 203 starts operation from a state where the current position of the forklift 200 is grasped.

In S12, the control section 203 continues shooting and moving.

In S13, the control unit 203 determines whether the mark 1 is detected or not from the image captured by the camera 201. If the mark 1 is detected, the routine proceeds to S14, and if the mark 1 is not detected, the routine returns to S12 and repeats the detection operation of the mark 1.

In S14, the control unit 203 recognizes the mark 1 on which tray P the mark 1 is provided by a pattern (recognition mark 5).

In S15, the calculation unit 202 calculates the relative position between the camera 201 and the marker 1 based on the mark 2 in the image captured by the camera 201.

In S16, the control unit 203 controls the operation of the forklift 200 based on the operation result of the operation unit 202. For example, the up-down position of the fork 200a, or the position of the fork truck 200.

In S17, the control unit 203 determines whether or not to end the operation, returns to S12 when the operation is continued, and ends the operation when the operation is not continued.

The above steps are performed in a computer by an application program for the measurement system.

As described above, according to the measuring system 500 of the present embodiment, by providing the mark 1 on the pallet P as the object to be measured, the relative positional relationship between the pallet P and the forklift 200 can be measured (grasped) with very high accuracy, and the forklift 200 can be appropriately controlled.

(embodiment 7)

Fig. 31 is a diagram showing embodiment 7 of the mark of the present invention.

The mark 1 of embodiment 7 includes a mark 2 and an identification mark 5. The mark 1 of embodiment 7 is the same as that of embodiment 6 except that it does not include moire display regions 3 and 4. Therefore, portions that realize the same functions as those of the above-described embodiments are given the same reference numerals, and overlapping descriptions are appropriately omitted.

In embodiment 7, arUco is used for the identification mark 5. ArUco is a technique disclosed in the Internet URL below.

"Detection of ArUco Marker" [ order and 4, 3, 23, search ], internet < URL: https: pecv/org/4. X/d 5/dae/tutorial_arc_detetection.

In this web page, a scheme of performing position and orientation measurement using ArUco is also described. The measurement of the position and orientation using the ArUco can be performed in the same manner as the measurement of the position and orientation using the mark 2 described above. Further, the measurement of the position and orientation using the mark 2 can be performed with higher accuracy than the measurement of the position and orientation using the ArUco.

In the present embodiment, the position and orientation are measured using the marks 2. However, in the measurement of the position and orientation using the mark 2, if the mark 2 is not properly captured by the camera (capturing unit) 201, accurate measurement cannot be performed. For example, if a part of the mark 2 is contaminated, blocked by an obstacle, or is unclear due to reflection of light, the position and orientation cannot be accurately measured.

Therefore, in the present embodiment, the constitution is as follows: in addition to the measurement of the position and orientation using the mark 2, the measurement of the position and orientation using the identification mark 5 (ArUco) is performed in parallel. The measurement operation will be described later.

In the present embodiment, since the position and orientation of the identification mark 5 are also measured, the identification mark 5 is configured in the same manner as the mark 2, and is formed in the same manner as the mark 2 by the photolithography step. This can improve the accuracy of measurement of the position and orientation using the identification mark 5. The method of forming the identification mark 5 is the same as that of the mark 2, and is performed simultaneously with the formation of the mark 2, and therefore, a detailed description thereof will be omitted. In addition, in the case of giving priority to convenience over accuracy, the identification mark 5 may be formed by printing, or may be formed by attaching a label or a sticker on which the identification mark 5 is printed separately.

In the production of the mark 1 according to embodiment 7, a plurality of marks 1 are arranged in an array, that is, a multi-surface mark array 100 in which a plurality of marks 1 are arranged along a surface is produced. Then, each of the marks 1 is cut out from the multi-surface mark array 100 and singulated, thereby obtaining the marks 1.

In the polyhedral mark array 100 shown in fig. 32, 4 ArUco id=0 are arranged for the uppermost row of mark 1 in the figure. Then, the ids=1 of the 4 arucco are arranged in the next row, the ids=2 of the 4 arucco are arranged in the next row, the ids=3 of the 4 arucco are arranged in the next row, the ids=4 of the 4 arucco are arranged in the next row, and the ids=5 of the 4 arucco are arranged in the next row. That is, the configuration is performed by changing the ID of ArUco for each row. Further, the present invention is not limited to such an arrangement, and for example, arucc (identification mark 5) having the same ID may be arranged for all the marks 1 in the 1-multifaceted mark array 100, or arucc (identification mark 5) having different IDs may be arranged for all the marks 1.

The mark 1 of the present embodiment is attached to, for example, a pallet P for logistics, as in embodiment 6, and can be used when the pallet P is identified as a detection object. The structure of the tray P to which the mark 1 of embodiment 7 is attached is the same as that of embodiment 6.

The configuration of the measurement system 500 including the mark 1 of embodiment 7 is the same as that of the measurement system 500 of embodiment 6 except that part of the processing in the arithmetic unit 202 is different. The arithmetic unit 202 of the present embodiment can perform the same operations as those of the arithmetic examples 1 to 4 in embodiment 6. At this time, the position and orientation of the identification mark 5 (ArUco) are measured in parallel with the position and orientation of the mark 2.

When the position and orientation using the mark 2 can be appropriately measured, the calculation unit 202 outputs a measurement result of the position and orientation using the mark 2.

On the other hand, when a part of the mark 2 is hidden or the like and cannot be properly photographed, the calculation unit 202 outputs a measurement result using the position and orientation of the identification mark 5 (ArUco).

In S21, the control unit 203 starts shooting by the camera 201 and movement of the forklift 200. In this example, for simplicity, the control unit 203 will be described as starting from a state in which the current position of the forklift 200 is grasped.

In S22, the control unit 203 continues shooting and moving.

In S23, the control section 203 determines whether the mark 1 is detected based on the image captured by the camera 201. If the mark 1 is detected, the routine proceeds to S24, and if the mark 1 is not detected, the routine returns to S22 and repeats the detection operation of the mark 1.

In S24, the control unit 203 recognizes the mark 1 as the mark 1 of which tray P the mark 1 is provided on by a pattern (recognition mark 5).

In S25, the calculation unit 202 performs calculation of the relative position between the mark 1 and the camera 201 (forklift 200) using the mark 2 (hereinafter referred to as "1 st calculation process").

In S26, the calculation unit 202 performs calculation of the relative position between the mark 1 and the camera 201 (forklift 200) using the pattern (identification mark 5) (hereinafter referred to as "2 nd calculation process").

The 1 st arithmetic processing in S25 and the 2 nd arithmetic processing in S26 are performed in parallel. The term "parallel operation processing" is not limited to the case of completely parallel operation (so-called parallel operation), but includes substantially simultaneous operation processing such as immediately performing the 2 nd operation processing after the 1 st operation processing and immediately performing the 1 st operation processing after the 1 st operation processing. That is, the mode is not to continue the 1 st arithmetic processing but not to normally continue the 2 nd arithmetic processing, but to continue both arithmetic processing. Thus, the operation results of both the 1 st operation process and the 2 nd operation process can be immediately output without time lag.

In S27, the arithmetic unit 202 determines whether or not the relative position between the mark 1 and the camera 201 (forklift 200) can be calculated by the 1 st arithmetic processing. If the calculation of the relative position is possible, the process proceeds to S28, and if the calculation of the relative position is not possible, the process proceeds to S29.

In S28, the operation unit 202 outputs the result of the operation of the relative position between the mark 1 and the camera 201 (forklift 200) obtained by the 1 st operation processing to the control unit 203.

In S29, the operation unit 202 outputs the result of the operation of the relative position between the mark 1 and the camera 201 (forklift 200) obtained by the 2 nd operation to the control unit 203.

In S30, the control unit 203 controls the operation of the forklift 200 based on the result of the operation by the operation unit 202. For example, the up and down position of the fork 200a, or the position of the fork truck 200.

In S31, the control unit 203 determines whether or not to end the operation, returns to S22 when the operation is continued, and ends the operation when the operation is not continued.

The above steps are executed by a computer by an application program for a measurement system.

For example, as shown in fig. 36, when two marks 2 cannot be properly captured due to the obstacle S, the calculation unit 202 cannot calculate the relative positions of the mark 1 and the camera 201 (forklift 200) using the marks 2. In this case, the flow advances to S29, where the operation unit 202 outputs the result of the operation of the relative position between the mark 1 and the camera 201 (forklift 200) calculated using the pattern (identification mark 5) to the control unit 203. This can avoid a situation in which the control of the forklift 200 is disabled due to the inability of the calculation. If the obstacle S moves and the like during the control of the forklift 200 thereafter and the mark 2 can be properly captured, the determination of S27 is yes, and thus the control by the 1 st arithmetic processing can be restored.

As described above, according to embodiment 3, the position and orientation measurement (the 2 nd arithmetic processing) using the figure (the identification mark 5) is performed in parallel with the position and orientation measurement (the 1 st arithmetic processing) using the mark 2, and therefore, the position and orientation measurement can be continued without interruption even in a case where the mark 2 cannot be properly captured.

(modification mode)

The present invention is not limited to the above-described embodiments, and various modifications and alterations are possible, and they are also within the scope of the present invention.

(1) In embodiments 1 to 3, the description has been given taking an example in which the symbol 2 is black and the periphery thereof is white. For example, the mark 2 may be white and the periphery may be black.

More specifically, for example, in embodiment 1, the 1 st layer 20 may be white and the 2 nd layer 30 on the observation side may be black.

Fig. 12 and 13 are diagrams showing modifications of embodiment 1 in which layer 1 20 is white and layer 2 30 is black.

As shown in fig. 13, the 1 st layer 20 of embodiment 1 is white and the 2 nd layer 30 on the observation side is black, whereby the mark 2 is white and the periphery thereof is black as in the mark 1 shown in fig. 12.

For example, in embodiment 3, the 1 st layer 20C may be black and the 2 nd layer 30C on the observation side may be white.

Fig. 14 and 15 are diagrams showing modifications in which layer 1 20C is black and layer 2 30C is white in embodiment 3.

As shown in fig. 15, the 1 st layer 20C of embodiment 3 is black, and the 2 nd layer 30 on the observation side is white, whereby the mark 2 is white and the periphery thereof is black as in the mark 1C shown in fig. 14.

(2) In embodiment 1 to embodiment 3, the explanation has been given by taking an example in which the symbol 2 is displayed using two colors of black and white. For example, the color is not limited to this, and may be formed by combining other colors such as blue and yellow. Further, a 3 rd layer observed as 3 rd color may be added, and a structure in which more layers observed as 3 or more colors are stacked may be made. In addition, the difference in color in the present invention is not limited to the difference in color exhibited by the combination of RGB, but can also include the difference exhibited by the single-color multi-gradation expression.

(3) In embodiments 1 to 3, the description has been given taking an example in which the symbol 2 can be observed under visible light. For example, the mark 2 may be detected using light in a specific wavelength region such as an infrared light region (near infrared light wavelength region of 780nm or more). More specifically, for example, the mark 2 may be observed in the near infrared light region, the mark 2 may not be observed in the white light (visible light) region, or the mark 2 may be inconspicuous. If the marks 2 are formed of a near-infrared absorbing material, the marks 2 can be recognized by the near-infrared light receiving element only when the near-infrared light is irradiated, and cannot be recognized by the human eye. As the near infrared ray absorbing material, known materials such as ITO, ATO, cyanine compounds, phthalocyanine compounds, dithiol metal complexes, naphthoquinone compounds, diimmonium compounds, azo compounds, and the like can be used. This can be used for a use where the mark 1 (B) is not intended to be highlighted.

In this case, it is preferable that the contrast value between the 1 st color of the 1 st layer 20 and the 2 nd color of the 2 nd layer 30 is 0.26 or more when viewed using light in a specific wavelength region, and the contrast value between the 1 st color and the 2 nd color is 1.0 or less when viewed using visible light. This makes it possible to detect a position with high accuracy under light in a specific wavelength range while being inconspicuous under visible light.

(4) In embodiment 1 to embodiment 3, the structure in which the protective layer 70 is attached by the adhesive layer 60 is exemplified. For example, the protective layer may be directly laminated on the 2 nd layer 30, or the protective layer may be omitted depending on the use environment.

(5) In embodiment 1 to embodiment 3, an example was described in which the mask M was used in the 2 nd exposure step of exposing the mark pattern to the 2 nd layer 30. For example, the exposure of the mark pattern may be performed by a direct drawing method using a laser.

(6) In embodiment 1 to embodiment 3, description has been made taking an example in which the 1 st layer 20 can be observed as a mark of an independent shape. For example, the present invention may be configured as: layer 2 30 can be viewed as an independent shaped symbol. In this connection, the resist material forming the 2 nd layer 30 may be either positive or negative.

(7) In embodiment 1 to embodiment 3, a layer for improving adhesion, a layer for improving surface properties, a layer for diffusing light to form an antiglare effect, or the like may be appropriately interposed between the layers, the frontmost surface, or the like.

(8) In embodiment 3, an example in which the planarizing layer 91 is provided is described. Such a planarizing layer may be provided in embodiment 1.

Fig. 16 is a cross-sectional view showing a modification in which a planarizing layer 91 is provided in an opening 30a of the layer 2 30 of embodiment 1.

As shown in fig. 16, by providing the planarizing layer 91 in the opening 30a of the 2 nd layer 30, occurrence of voids can be prevented.

In addition, although the example in which the height of the planarization layer 91 is lower than that of the 2 nd layers 30 and 30C is shown in the embodiment of fig. 16 and 3 rd embodiment, the height of the planarization layer 91 may be slightly higher than that of the 2 nd layers 30 and 30C, and more preferably the same height as that of the 2 nd layers 30 and 30C.

(9) In embodiment 4, an example was described in which the 1 st layer 20 was black and the 2 nd layer 30 was white. For example, the 1 st layer 20 may be white and the 2 nd layer 30 may be black, and the composition is not limited to a combination of black and white, but may be a combination of blue and yellow.

(10) In embodiment 4, the description has been given by taking an example in which the black portion of the mark 2 and the 1 st pattern 23 are formed by the 1 st layer 20. For example, the mark 2 and the 1 st pattern 23 may be provided on different layers.

(11) In embodiment 4, a structure in which the protective layer 70 is attached by the adhesive layer 60 is exemplified. For example, the protective layer may be directly laminated on the 2 nd layer 30, or the protective layer may be omitted depending on the use environment.

(12) In embodiment 4, an example has been described in which the moire display region 3 and the moire display region 4 are arranged so that their longitudinal directions are orthogonal. For example, a moire display region may be further added. In this case, the longitudinal direction of the additional moire display region may be arranged in a direction intersecting the moire display region 3 and the moire display region 4 at an angle of 45 degrees or the like. With such a configuration, the accuracy of position detection can be further improved.

(13) In embodiment 5, an example was described in which a sheet member was attached to a light diffusion layer. For example, the light diffusion layer may be formed by coating a resin or the like.

(14) In embodiment 5, an example was described in which the light diffusion layer has fine irregularities on the front surface. For example, the light diffusion layer may have a structure having light diffusion particles therein, or may have both fine irregularities on the front surface and light diffusion particles therein.

(15) In embodiment 5, an example was described in which the light diffusion layer is provided in a partially island shape. For example, the light diffusion layer may be provided on the entire surface of the mark.

(16) In embodiment 5, an example in which the 1 st layer 20 is black and the 2 nd layer 30 is white is described. For example, as shown in fig. 26, the 1 st layer 20 may be white and the 2 nd layer 30 may be black, and the composition is not limited to a combination of black and white, but may be a combination of other colors such as blue and yellow. Further, a 3 rd layer or the like observed as 3 rd color may be added, and a structure in which more layers observed as 3 or more colors are stacked may be made. The difference in color in the present invention is not limited to the difference in color expressed by the combination of RGB, and may include a difference expressed by a single-color multi-gradation expression.

(17) In each embodiment, an example was described in which the resist material composition was used for each of the 1 st layer 20 and the 2 nd layer 30. For example, the 1 st layer 20 and the 2 nd layer 30 may be formed by laminating thermosetting resins on the necessary portions by an inkjet method. Even in such a case, the linear expansion coefficient of the base material layer 10 is set to 10×10 ^-6 Even at a temperature of not higher than/DEG C, sufficient accuracy can be ensured depending on the application.

(18) In embodiment 6, an example in which the measurement system of the present invention is applied to control of the forklift 200 has been described. The measurement system of the present invention is not limited to this, and can be applied to various fields. For example, the marker 1 may be disposed in various places in a room, and may be applied to movement control of various conveyers, robots, and the like that move in the room. The present invention may be applied to movement control of various conveyors, robots, and the like that move in a room by arranging cameras around the room and arranging marks on various conveyors, robots, and the like that move in the room. Further, the present invention is not limited to the indoor space, and may be applied to the outdoor space for movement control of an unmanned aerial vehicle or the like. In addition, the present invention may be used for various measurements of infrastructure such as a construction site, a dam, or a bridge, without performing movement control.

(19) In embodiment 6, an example in which the measurement system of the present invention is applied to control of the forklift 200 has been described. Without being limited thereto, the constitution may be as follows: the control unit is not provided, and only the measurement result is obtained.

(20) In embodiment 7, description has been made by taking an example in which measurement of the position and orientation using the mark 2 (the 1 st arithmetic processing) and measurement of the position and orientation using the pattern (the identification mark 5) are performed in parallel (the 2 nd arithmetic processing). For example, in the case of an application in which time lag in computation switching does not become a problem, the following means may be used: only the 1 st arithmetic processing is continued, and normally the 2 nd arithmetic processing is not performed, but only when the 1 st arithmetic processing cannot be performed, the processing is switched to the 2 nd arithmetic processing.

(21) In embodiment 7, description has been made taking an example in which the mark 1 is attached to the tray P and used. For example, the tag 1 may be attached to a shelf on which articles are displayed for use.

In the example shown in fig. 37, a mark 1 is attached to the shelf T at the intersection (intersection point) of the shelf T1 and the column T2 of the shelf T. Also, arUco, which is the identification mark 5 provided on the tag 1, is assigned a different ID.

In this case, the camera, the calculation unit, and the control unit are provided in the automatic conveyer (robot) 300, and the automatic conveyer 300 can accurately grasp the crossing position (crossing point) with the column T2 of the rack T by capturing the mark 1 and measuring the position of the mark 1. The shelf can be specified based on the information obtained from the identification mark 5, and the automatic conveyor 300 can be automatically controlled to move to an appropriate position, and can be automatically operated to perform replenishment, exchange, pickup, and the like of the articles placed on the shelf T. The structure can be applied to, for example, a commodity shelf in a store, a shelf located in a warehouse, a factory, or the like.

(22) In embodiment 7, description has been made taking an example in which the mark 1 is attached to the tray P and used. For example, the mark 1 may be attached to a windshield of an automobile.

In fig. 38, a state in which the automobile 401 and the automobile 402 are parked in a parking lot is shown.

In the example shown in fig. 38, the ID of the identification mark 5 of the mark 1 attached to the windshield of the automobile 401 is different from the ID of the identification mark 5 of the mark 1 attached to the windshield of the automobile 402.

A camera (imaging unit) 450 is disposed in the parking lot, and images the vehicle parked in the parking lot, and is connected to an unillustrated arithmetic unit. The vehicle shape, weight, number, owner, etc. are associated as data for each ID of the identification mark 5 of each tag 1. Accordingly, the payment of the fee for the parking lot can be automated based on the photographing result of the camera 450. In addition, by performing position measurement using the mark 1, it is possible to accurately grasp which car is stopped at which position. Therefore, when the vehicle is parked at the wrong position, the notification of the intention can be made or the worker can be prompted to respond. In addition, in the case of an automobile, it is assumed that the windshield is contaminated with defoliation, mud, or the like, but even in such a case, by performing both the 1 st arithmetic processing and the 2 nd arithmetic processing, a situation in which position measurement cannot be performed can be avoided.

In addition, arUco of the identification mark 5 is different from the number of the car, and cannot be easily interpreted by an ordinary person only at a glance, so that privacy protection can be facilitated.

Further, a system for reading a license plate and for payment of a fee has been put to practical use, but the position/orientation cannot be measured with high accuracy by the license plate. In contrast, by using the mark 1, the position of the vehicle can be accurately grasped in the entire parking lot.

In addition, although the embodiments and modifications can be appropriately combined and used, a detailed description thereof is omitted. The present invention is not limited to the above-described embodiments.

Description of the reference numerals

1. 1B, 1C: marking;

2: marking;

3. 4: moire fringe display areas;

5: identifying the mark;

10: a substrate layer;

20. 20C: layer 1;

21: 1 st display line;

22: 1 st non-display area;

23: pattern 1;

30. 30C: layer 2;

30a: an opening portion;

31: an opening portion;

32: an opening portion;

40: layer 3;

41: a 2 nd display line;

42: a 2 nd non-display area;

43: pattern 2;

50: a reflective layer;

60: an adhesive layer;

70: a protective layer;

71: a resin base material layer;

72: a front layer;

80: a light diffusion layer;

81: a resin base material layer;

82: a front layer;

91: a planarization layer;

92: an intermediate layer;

100: a multi-faceted marker arrangement;

200: a fork truck;

201: a camera (photographing section);

202: an arithmetic unit;

203: a control unit;

300: an automatic conveyor;

401. 402: an automobile;

450: a camera (photographing section);

500: a measurement system.

Claims

1. A measurement system, comprising:

marking;

A photographing unit that photographs the mark; and

a calculation unit that calculates at least one of a relative positional relationship between the imaging unit and the marker, a size of an object in the vicinity of the marker or a distance between specified positions, a distance between the markers in which a plurality of the markers are arranged, and a posture of the marker, using the image of the marker imaged by the imaging unit,

wherein,

the mark is provided with:

a substrate layer;

a 1 st layer which is laminated on the observation side of the base material layer and is observed as a 1 st color; and

a layer 2 which is partially laminated on the observation side of the layer 1, is observed as a 2 nd color different from the 1 st color, and partially shields the layer 1,

the layer 1 can be observed in the region where the layer 2 is not laminated,

the 2 nd layer is composed of a resist material.

2. The measurement system of claim 1, wherein the measurement system comprises a sensor,

the 1 st layer is composed of a resist material.

3. A measurement system, comprising:

marking;

a photographing unit that photographs the mark; and

Wherein,

the mark is provided with:

a substrate layer;

a 1 st layer which is laminated on the observation side of the base material layer and is laminated on the entire surface of the base material layer, and is observed as a 1 st color; and

the layer 1 can be observed in the region where the layer 2 is not laminated,

the linear expansion coefficient of the substrate layer is 10×10 ^-6 And/or lower.

4. A measuring system according to any one of claims 1 to 3, characterized in that,

the substrate layer is composed of glass.

5. A measuring system according to any one of claims 1 to 3, characterized in that,

one of the layers 1 and 2 can be viewed as a mark of an independent shape,

the marks are arranged at intervals of 3 or more.

6. The measurement system of claim 5, wherein the measurement system comprises a sensor,

the measurement system is configured with a pattern for identification,

the arithmetic unit refers to the pattern to identify the mark.

7. The measurement system of claim 6, wherein the measurement system comprises a sensor,

The arithmetic unit performs the following arithmetic processing:

a 1 st operation process of calculating at least one of a relative positional relationship between the imaging unit and the mark, a size of an object in the vicinity of the mark or a distance between specified positions, a distance between the marks where a plurality of the marks are arranged, and a posture of the mark, based on an image of the mark included in the image of the mark; and

and a 2 nd arithmetic processing of calculating at least one of a relative positional relationship between the imaging unit and the marker, a size of an object in the vicinity of the marker or a distance between specified positions, a distance between the markers in which a plurality of the markers are arranged, and a posture of the marker, based on an image of the recognized pattern included in the image of the marker.

8. The measurement system of claim 7, wherein the measurement system comprises a sensor,

the operation unit outputs the operation result of the 1 st operation process when the 1 st operation process is able to perform the operation appropriately, and outputs the operation result of the 2 nd operation process when the 1 st operation process is unable to perform the operation appropriately.

9. The measurement system of claim 8, wherein the measurement system comprises a sensor,

the arithmetic unit performs the 1 st arithmetic processing and the 2 nd arithmetic processing in parallel.

10. A measuring system according to any one of claims 1 to 3, characterized in that,

the measurement system includes a control unit that controls the measurement system based on the calculation result of the calculation unit.

11. A measuring method of a measuring system according to any one of claims 1 to 3, wherein,

the measurement method of the measurement system comprises the following steps:

the photographing part photographs the mark; and

the computation unit computes at least one of a relative positional relationship between the imaging unit and the marker, a size of an object in the vicinity of the marker or a distance between specified positions, a distance between the markers where a plurality of the markers are arranged, and a posture of the marker, using the image of the marker imaged by the imaging unit.

12. A program of a measuring system according to any one of claims 1 to 3, wherein,

the program of the measuring system is for causing a computer to execute the steps of:

The photographing part photographs the mark; and