Scale, encoder, and scale manufacturing method

Abstract

The invention discloses a scale, an encoder and a scale manufacturing method. The scale manufacturing method includes: forming a metal-containing layer on a resin layer provided on at least a first surface of a substrate; forming a contour of the pattern on the metal-containing layer by irradiating the metal-containing layer with a first laser light from a side opposite to the substrate; irradiating a second laser from one side of a second surface opposite to the first surface of the base material to a side part outside the outline of the metal-containing layer; and peeling off a portion of the metal-containing layer corresponding to the edge portion.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2023-146193, filed on September 8, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0003] Certain aspects of the embodiments described herein relate to scales, encoders, and scale manufacturing methods. Background Art

[0004] A ruler in which a conductive pattern is formed on a substrate has been disclosed (see, for example, Japanese Patent Application Publication No. 2018-031777, Japanese Patent Application Publication No. 2003-241392, and Japanese Patent Application Publication No. 2016-044967). Summary of the invention

[0005] In one aspect, the present invention aims to provide a scale, an encoder and a scale manufacturing method, whose conductor pattern can be formed in a short time while reducing the use of chemicals that have a high impact on the environment.

[0006] According to one aspect of the present invention, a scale manufacturing method is provided, comprising: forming a metal-containing layer on a resin layer arranged on at least a first surface of a substrate; forming an outline of a pattern on the metal-containing layer by irradiating a first laser to the metal-containing layer from a side opposite to the substrate; irradiating a second laser to an edge outside the outline of the metal-containing layer from a side of a second surface of the substrate opposite to the first surface; and peeling off a portion of the metal-containing layer corresponding to the edge.

[0007] According to one aspect of the present invention, there is provided a ruler comprising: an optically transparent substrate having a resin layer on a first surface thereof; and a plurality of conductor patterns, the plurality of conductor patterns being arranged on the resin layer and having a structure in which a plurality of metal grids are formed at certain intervals, wherein a spot pattern is formed at certain intervals along a two-dimensional direction on an area of ​​the resin layer other than the conductor patterns. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1A is a diagram showing a configuration of an electromagnetic induction encoder 1000 including a scale according to a first embodiment;

[0009] Figure 1B A sine wave signal having a period identical to the fundamental period λ is shown;

[0010] Figure 1C is a diagram showing a transceiver coil and a receiver coil provided in a detection head;

[0011] Figure 2A is a plan view showing a scale according to a first embodiment;

[0012] Figure 2B is along Figure 2A A cross-sectional view taken along line AA in FIG.

[0013] FIG. 3A to FIG. 3F is a diagram showing a method of manufacturing a scale;

[0014] Figure 4 It is a plan view of the ruler as seen from above;

[0015] Figure 5 is a diagram showing a speckle pattern;

[0016] 6A to 6F is a diagram showing a method of manufacturing a scale;

[0017] Fig. 7A is a plan view showing a scale according to a second embodiment;

[0018] Figure 7B is along Fig. 7A A cross-sectional view taken along line AA in FIG.

[0019] FIG. 8A to FIG. 8D is a diagram showing a method of manufacturing a scale;

[0020] Fig. 9 is a plan view showing a scale;

[0021] Fig.10 is a diagram showing a scale;

[0022] Fig.11 is a diagram showing a scale; and

[0023] Fig.12 It is a diagram showing a scale. DETAILED DESCRIPTION

[0024] For example, a conductor pattern can be formed by processing a thick copper foil on the surface of a material such as a printed circuit board using photolithography and wet etching. However, wet etching requires the use of chemicals with a high environmental impact. Therefore, it has been considered to use laser processing to form a conductor pattern. However, it takes a long time to form a conductor pattern using laser processing.

[0025] The following is a description of embodiments with reference to the accompanying drawings.

[0026] (First embodiment) Figure 1A 1 is a diagram showing a configuration of an electromagnetic induction encoder 1000 including a scale 100 according to a first embodiment. Figure 1AAs shown, the electromagnetic induction encoder 1000 includes a scale 100 and a detection head 40 that moves relatively in the measurement axis direction. The scale 100 and the detection head 40 each have a substantially flat plate shape and are arranged opposite to each other with a predetermined gap therebetween. The electromagnetic induction encoder 1000 also includes a transmission signal generator 50 and a displacement amount measurer 60. Figure 1A In FIG. 1 , the X axis indicates the displacement direction (measurement axis) of the detection head 40. In the plane formed by the scale 100, the direction perpendicular to the X axis is defined as the Y axis. The direction perpendicular to the plane formed by the scale 100 is defined as the Z axis.

[0027] The detection head 40 is provided with a transceiver coil 42 and a receiver coil 44. The transceiver coil 42 is a rectangular coil having a length in the X-axis direction. The receiver coil 44 is provided inside the transceiver coil 42.

[0028] The ruler 100 is provided with a plurality of conductor patterns 23 made of a conductor on a first surface of a substrate 21. The plurality of conductor patterns 23 are arranged with a basic period λ along the X-axis direction. The basic period λ corresponds to the distance between the centers of two adjacent conductor patterns 23 in the X-axis direction. The conductor pattern 23 is, for example, a plate-like pattern without a hole or a closed-loop coil. The conductor pattern 23 is electromagnetically coupled to the transceiver coil 42 and is also electromagnetically coupled to the receiver coil 44.

[0029] The transmission signal generator 50 generates a transmission signal of a single-phase AC and supplies the generated transmission signal to the transceiver coil 42. In this case, a magnetic flux is generated in the transceiver coil 42. Therefore, an electromotive force current is generated in the plurality of conductor patterns 23. The plurality of conductor patterns 23 are electromagnetically coupled with the magnetic flux generated by the transceiver coil 42, and generate a magnetic flux that fluctuates in the X-axis direction in a predetermined spatial period. The magnetic flux generated by the conductor pattern 23 generates an electromotive force current in the receiver coil 44. The electromagnetic coupling between the conductor pattern 23 and the receiver coil 44 fluctuates according to the displacement amount of the detection head 40. Thus, a sinusoidal wave signal of the same period as the basic period λ is obtained. Therefore, the receiver coil 44 detects the phase of the magnetic flux generated by the plurality of conductor patterns 23.

[0030] The displacement measuring device 60 can use the sine wave signal as a digital quantity with minimum resolution through electrical interpolation and measure the displacement of the detection head 40. Figure 1B , the horizontal axis represents the displacement of the detection head 40 , and the vertical axis represents the output voltage of the receiver coil 44 .

[0031] The transceiver coil 42, the receiver coil 44 and the conductor pattern 23 that are electromagnetically coupled to each other form a track. Therefore, in this embodiment, the electromagnetic induction encoder 1000 has one track. In addition, the electromagnetic induction encoder 1000 may have two tracks arranged at a predetermined interval in the Y-axis direction. In this case, the basic period λ between the two tracks may be different. This allows it to be used as an absolute (ABS) encoder.

[0032] Figure 1C 4 is a diagram showing a transceiver coil 42 and a receiver coil 44 provided in the detection head 40. Figure 1C As shown, the receiver coil 44 is disposed inside the transceiver coil 42, which forms a rectangular coil. The receiver coil 44 is, for example, a circular coil, but may have other configurations.

[0033] Figure 2A is a plan view showing a scale 100 according to the first embodiment. Figure 2B is along Figure 2A A cross-sectional view taken along line AA in FIG. Figure 2A and Figure 2B As shown, a resin layer 22 is formed on the first surface of the substrate 21. A conductor pattern 23 is formed on the resin layer 22, wherein a plurality of metal grids are arranged at predetermined intervals along the X-axis direction. In a plan view observed from the +Z direction, the plurality of conductor patterns 23 have a substantially rectangular shape with the Y-axis direction as the longitudinal direction. The metal grids are spaced apart from each other. The resin layer 22 may cover the entire first surface of the substrate 21. The resin layer 22 preferably covers at least the entire area where the conductor pattern 23 is provided. The conductor pattern 23 may be covered by a protective film or the like, but may be exposed to the atmosphere.

[0034] The substrate 21 is not particularly limited as long as it has optical transparency. The substrate 21 is, for example, glass. Examples of glass that can be used include quartz glass, soda-lime glass, and non-alkaline glass. Quartz glass is a glass that is almost entirely composed of silicon dioxide (SiO2) and contains very few impurities. Soda-lime glass is a glass that is mainly composed of silicon dioxide (SiO2) and also contains sodium oxide (Na2O) and calcium oxide (CaO). Non-alkaline glass is a glass that is mainly composed of silicon dioxide (SiO2) and does not contain alkaline components such as sodium and potassium. The thickness of the substrate 21 is, for example, about 0.4 mm or more and about 6.0 mm or less.

[0035] The resin layer 22 is not particularly limited as long as it is an adhesive resin having optical transparency. Examples of the resin layer 22 include epoxy resin, polyimide, polyurethane, acrylic resin, and the like.

[0036] The conductor pattern 23 is not particularly limited as long as it is metal. The conductor pattern 23 is formed of a conductor such as copper, silver, gold or aluminum. The thickness of the conductor pattern 23 is, for example, about 3 μm to 30 μm. The width of the conductor pattern 23 in the X-axis direction is, for example, about 500 μm to 3000 μm. The interval between the conductor patterns 23 (from one end of the conductor pattern 23 to the other end of the adjacent conductor pattern 23) is also, for example, about 500 μm to 3000 μm.

[0037] Next, a method for manufacturing the scale 100 will be described. First, Figure 3A As shown, an adhesive resin is applied to the first surface of the upper side of the substrate 21 to form a resin layer 22. For example, the resin layer 22 is formed to have a thickness of 30 μm. For example, a liquid adhesive resin may be uniformly applied to the first surface of the substrate 21, or a sheet-like adhesive resin may be laminated. Thereafter, a metal foil 24 (metal-containing layer) is attached to the resin layer 22 by heat lamination or hot pressing.

[0038] Alternatively, a flexible printed circuit board material in which the resin layer 22 and the metal foil 24 are bonded together to form an integral mold may be attached to the base material 21. As the metal foil 24, a copper foil having a thickness of 12 μm may be used, for example.

[0039] Next, if Figure 3B As shown, ultrashort pulse laser treatment is performed by irradiating the metal foil 24 with an ultrashort pulse laser (first laser) having a width of about 10 μm to 50 μm from the opposite side of the substrate 21. Ultrashort pulse laser is a laser having an extremely short pulse width (time width) of the order of picoseconds to femtoseconds, and can irradiate at a repetition frequency of, for example, 10 kHz to 4 MHz at equal time intervals. By ultrashort pulse laser treatment, as Figure 3C As shown, a groove 25 corresponding to the outline of the conductor pattern 23 is formed in the metal foil 24. For example, the ultrashort pulse laser processing can be performed using a current scanner, or the ultrashort pulse laser processing can be performed by moving the workpiece on a precision stage to change the laser spot position on the workpiece. The processed end surface is smooth and tapered so that the cross section of the groove 25 has a V-shaped groove structure. The groove 25 reaches the resin layer 22. Alternatively, the groove 25 may reach the upper surface of the substrate 21 and be formed deeper than the upper surface of the substrate 21.

[0040] Next, if Figure 3DAs shown, at the interface between the resin layer 22 and the metal foil 24, a short pulse laser having a wavelength that transmits glass or resin is focused and irradiated from the second side of the substrate 21 opposite to the first side. The short pulse laser is a laser that has a pulse width (time width) of 1 to 100 nanoseconds and repeatedly irradiates at time intervals of 10 kHz to 1 MHz. For example, an infrared nanosecond laser can be used as the short pulse laser. When the short pulse laser is scanned on the outer side (edge) of the contour formed by the groove 25, heat is generated at the interface between the resin layer 22 and the metal foil 24 mainly in the edge, and the surface of the resin layer 22 changes and loses adhesion. As a result, as shown in FIG. Figure 3E As shown, a gap may be generated between the resin layer 22 and the metal foil 24 in the edge portion.

[0041] The energy required to change the resin layer 22 is less than the energy required to remove the metal foil 24, and the process can be performed faster and with lower energy than directly removing the metal foil 24. In addition, when positioning the scanning position using a short pulse laser, it is not important whether the short pulse laser slightly protrudes to the width of the groove around the edge, so a low-precision current scanner can be used to perform positioning of the short pulse laser.

[0042] In addition, since a short pulse laser with a large spot that reduces the energy density of the irradiation pulse can be used, the removal process can be easily performed at high speed. For example, when an expensive ultrashort pulse laser is used to remove the groove from the front surface by laser ablation, in order to remove 5% of the pattern profile from the entire area, it is necessary to repeat the pulse irradiation 10 times at a 5μm pitch in the XY direction, where the laser output is 20W and the spot is Φ20μm. On the other hand, when a low-output, inexpensive infrared short pulse laser is used to perform a stripping process by scanning and irradiating from the back surface at the same speed as the ultrashort pulse laser, even if the area of ​​the edge is 50% (which is 10 times the area of ​​the groove), if the energy is 5W, the spot diameter is Φ40μm, and the pitch in the XY direction is 30μm, the number of pulse irradiations can be one, and the stripping can be completed with irradiation 1 / 360 times less per unit area, so the stripping work can be completed about 36 times faster than the removal process. Therefore, processing can be performed with good productivity using low-cost production equipment.

[0043] In addition, by combining the stripping process from the rear surface, the etching process time of the grooves required for the front surface can be shortened. In order to speed up the single product production time, there is no need to perform non-productive processing, such as etching processes that divide a large area using multiple ultrashort pulse lasers, which takes time and requires high equipment costs.

[0044] In addition, the surface after the stripping process is prone to stains and defects that are difficult to remove, such as scorching due to strong pulse energy, alternation of circuit surfaces or dust, glass powder and spattering of molten materials. If the entire large area is removed by the stripping process, many stains and defects may occur in proportion to the area. In the stripping process, stripping is performed with a single weak pulse, and the resin surface is only slightly changed, and no scorching or staining occurs, so there are almost no defects. Since the area of ​​the groove processing performed from the front surface before stripping is small, the occurrence of changes and contamination can be reduced.

[0045] Next, if Figure 3F As shown, the metal foil 24 in the edge portion scanned by the short pulse laser is peeled off. Thus, the conductor pattern 23 can be formed. For example, the metal foil 24 of the edge portion can be peeled off by applying an adhesive tape directly to the edge portion. Alternatively, the metal foil 24 of the edge portion can be peeled off by performing brush cleaning, purging with high-pressure air, ultrasonic cleaning with pure water, etc. The peeled metal can be collected and used as a recyclable resource.

[0046] Figure 4 1 is a plan view of the scale 100 as seen from the top side. Figure 4 As shown, on the top surface of the scale 100, a speckle pattern 27 generated by short-pulse laser irradiation can be seen on the top surface of the resin layer 22. For example, when circular spot light is irradiated as a short-pulse laser, a circular speckle pattern 27 is formed to be arranged at predetermined intervals in the two-dimensional directions of the X-axis and Y-axis directions. For example, the speckle pattern 27 is formed at predetermined intervals (e.g., 10 μm to 100 μm) along the X-axis direction, and is formed at predetermined intervals (e.g., 10 μm to 100 μm) along the Y-axis direction.

[0047] For example, the spot pattern 27 may be a visual pattern formed on the upper surface of the resin layer 22, or may be a concavo-convex pattern formed on the upper surface of the resin layer 22, such as Figure 5 As shown. The plane shape of the speckle pattern 27 is affected by the shape of the spot light of the short pulse laser. Therefore, if the spot light of the short pulse laser has an approximately circular shape, the plane shape of the speckle pattern 27 will also be approximately circular. If the spot light of the short pulse laser has an approximately rectangular shape, the plane shape of the speckle pattern 27 will also be approximately rectangular.

[0048] Next, another method of manufacturing the scale 100 will be described. First, Fig. 6A As shown, a primer resin adhesive is applied to the first face on the upper side of the substrate 21 to form the resin layer 22. For example, the resin layer 22 is formed to have a thickness of 5 μm.

[0049] Afterwards, a metal paste 26 (metal-containing layer) having high adhesion to the primer resin is screen-printed on the resin layer 22. As an example, a silver paste with a thickness of 10 μm can be used as the metal paste 26. The edge processing accuracy of the printed pattern is poor because the ink spreads, and film thickness distribution, edge roughness and printing distortion may occur. However, a metal film with a relatively flat and uniform thickness can be obtained near the center of the printed pattern. If the printed pattern is larger than the pattern required for the finished product (including the portion to be peeled off), a pattern with uniform thickness can be obtained. A rough conductor pattern can be obtained by firing after printing. In the case of a part with a complex shape that cannot be screen-printed, a conductor solid pattern, such as a metal foil, can be obtained by spraying or brushing a paste.

[0050] Next, if Figure 6B As shown, ultrashort pulse laser treatment is performed by irradiating ultrashort pulse laser with a width of about 10 μm to 50 μm to a position within the edge of a printed pattern having a uniform film thickness. By ultrashort pulse laser treatment, as Figure 6C As shown, a groove 25 corresponding to the outline of the conductor pattern 23 is formed in the metal paste 26. For example, the ultrashort pulse laser processing can be performed using a current scanner, or the workpiece can be processed while changing the laser spot position on the precision stage. The processed end surface is smooth and tapered so that the cross section of the groove 25 has a V-shaped groove structure. The groove 25 reaches the resin layer 22. Alternatively, the groove 25 may reach the upper surface of the substrate 21 and be formed deeper than the upper surface of the substrate 21.

[0051] Next, if Fig.6D As shown, a short pulse laser having a wavelength that transmits glass or resin is focused and irradiated to the interface between the resin layer 22 and the metal paste 26 from the second surface opposite to the first surface of the substrate 21. When the short pulse laser is scanned on the edge portion separated by the groove 25 (the area other than the conductor pattern 23), heat is generated mainly at the interface between the resin layer 22 and the metal paste 26 in the edge portion, and the surface of the resin layer 22 changes and loses adhesion. As a result, as shown in FIG. Fig. 6E As shown, a gap may occur between the resin layer 22 and the metal paste 26 in the edge portion.

[0052] The energy required to change the resin layer 22 is less than the energy required to remove the metal paste 26, and the process can be performed faster and with lower energy than directly removing the metal paste 26. In addition, since it is acceptable for the short pulse laser to protrude slightly beyond the width of the groove, a low-precision current scanner can be used to position the short pulse laser. Since defects are unlikely to occur even if a portion without a silver paste pattern is irradiated, it is acceptable to irradiate a certain wide range in consideration of the edge position variation of the paste pattern. If an attempt is made to remove a portion without paste or a portion with a film thickness distribution from the surface, the processing depth will vary over a wide range, and strong energy will be applied only to the portion of the resin, which will cause the resin to burn or peel off. The peeling process can reduce the possibility of defects compared to the case where the process is performed only by removal. In addition, it is acceptable to use a short pulse laser with a large spot, which reduces the energy density, making it easier to process at high speed.

[0053] Next, if Fig. 6F As shown, the metal paste 26 in the edge portion scanned by the short pulse laser is stripped. For example, the metal paste 26 in the edge portion can be stripped by applying an adhesive tape directly to the edge portion. Alternatively, the metal paste 26 in the edge portion can be stripped by brush cleaning, purging with high-pressure air, ultrasonic cleaning with pure water, etc. The stripped metal can be collected and used as a recyclable resource.

[0054] According to this embodiment, lithography, chemical etching, electroplating, etc. can be omitted, so that chemical solution management and waste liquid treatment are not required, and the number of processes can be reduced. In addition, since processing can be performed by direct drawing using a laser, circuits can be formed with good productivity even for elements of complex shapes that are difficult to use a photolithography process using a photomask.

[0055] (Second Embodiment) In the first embodiment, the scale having a structure in which the resin layer 22 is formed on the base material 21 is described, but in the second embodiment, the case in which the base material is made of resin is described.

[0056] Fig. 7A is a plan view showing a scale 100 a according to the second embodiment. Figure 7B is along Fig. 7A A cross-sectional view taken along line AA in FIG. Fig. 7A and Figure 7B As shown, a conductor pattern 23 having a plurality of metal grids arranged at predetermined intervals along the X-axis direction is formed on a first surface of a substrate 21. In this embodiment, the substrate 21 is made of a resin having optical transparency. In this way, the entire substrate 21 can be made of resin. In this embodiment, the thickness of the substrate 21 is, for example, about 0.1 mm or more and about 100 mm or less.

[0057] Although resin generally has a larger thermal expansion coefficient than glass or the like, resin has advantages that it is less likely to break, is light, thin, and allows for free formation of complex shapes. Therefore, the scale 100a according to this embodiment has advantages that it is less likely to break, is light, and allows for freedom of shape. For example, a portion having a shape in which a flat scale and a spindle to which it is attached are integrated can be scaled.

[0058] Next, a method for manufacturing the scale 100a will be described. Fig. 8A As shown, a metal foil 24 (metal-containing layer) is attached to a first face on the upper side of a base material 21 made of resin by heat lamination or heat pressing.

[0059] Next, if Figure 8B As shown, ultrashort pulse laser (first laser) is irradiated to metal foil 24 with a width of about 10 μm to 50 μm from the side opposite to substrate 21, thereby performing ultrashort pulse laser processing. The groove formed by ultrashort pulse laser processing reaches substrate 21. Alternatively, the groove may reach the top surface of substrate 21 and may be formed deeper than the top surface of substrate 21.

[0060] Next, if Figure 8C As shown, a short pulse laser having a wavelength that transmits glass or resin is focused at the interface between the substrate 21 and the metal foil 24, and the laser is irradiated from the second surface opposite to the first surface of the substrate 21. When the short pulse laser is scanned on the outside of the profile formed by the groove (edge), heat is generated mainly at the interface between the substrate 21 and the metal foil 24 in the edge, and the surface of the substrate 21 changes and loses adhesion.

[0061] Next, if Fig.8D As shown, the metal foil 24 in the edge portion scanned with a short pulse laser is peeled off. This allows the conductor pattern 23 to be formed. For example, the metal foil 24 in the edge portion can be peeled off by directly applying an adhesive tape to the edge portion. Alternatively, the metal foil 24 in the edge portion can be peeled off by performing brush cleaning, purging with high-pressure air, ultrasonic cleaning with pure water, etc. The peeled metal can be recovered and recycled.

[0062] In this embodiment, lithography, chemical etching, electroplating, etc. can be omitted, so that chemical solution management and waste liquid disposal are not required, and the number of processes can be reduced. In addition, since laser processing can be used, parts with complex shapes that are difficult to use photolithography processes, as well as resins that are not resistant to chemicals used in photolithography (such as those that dissolve and deform) can be formed.

[0063] The resin can be easily molded into various shapes using injection molding or a 3D printer. Therefore, the resin can be processed into various shapes, such as a column, a cylinder, a disk, or a sphere. For example, a ruler having these shapes can be used to form an encoder used in a robot joint. Note that even if the structure of the ruler has a resin layer on glass, the structure can be processed into these shapes.

[0064] For example, the scale 100 a may have an approximately circular shape in a plan view. Fig. 9 is a plan view showing the scale 100a in this case. Fig. 9 As shown, in the scale 100a, the base material 21 has an approximately circular shape in a plan view. The conductor patterns 23 are arranged on the first face on the upper surface side of the base material 21 at predetermined intervals along the periphery, on the inner side of the periphery. Fig. 7A In FIG. 1 , the conductor pattern 23 is arranged along the dotted line. The cross-sectional shape along the dotted line is as follows: Figure 7B shown.

[0065] Alternatively, the scale 100a may have a substantially cylindrical shape. Fig.10 is a diagram showing the scale 100a in this case. Fig.10 As shown, in the scale 100a, the base material 21 has a cylindrical shape. On the inner surface of the cylindrical shape, the conductor patterns 23 are arranged at predetermined intervals. For example, the conductor patterns 23 are arranged on the inner surface of the cylindrical shape along the circumferential direction.

[0066] Alternatively, the scale 100a may have a substantially cylindrical shape. Fig.11 is a diagram showing the scale 100a in this case. Fig.11 As shown, in the scale 100a, the base material 21 has a cylindrical shape. The conductor patterns 23 are arranged on the outer surface of the cylindrical shape at predetermined intervals. For example, the conductor patterns 23 are arranged along the axial direction of the cylindrical shape.

[0067] Alternatively, the scale 100a may have a substantially spherical shape. Fig.12 is a diagram showing the scale 100a in this case. Fig.12 As shown, in the scale 100a, the base material 21 has a spherical shape. The conductor patterns 23 are arranged at predetermined intervals around the outer circumference of the sphere. For example, the conductor patterns 23 are arranged along a predetermined circumference of the sphere.

[0068] The present invention is not limited to the specifically disclosed embodiments and variations, but may include other embodiments and variations without departing from the scope of the present invention.

Claims

1. A method for manufacturing a ruler, comprising: forming a metal-containing layer on the resin layer disposed on at least the first side of the substrate; forming a pattern profile on the metal-containing layer by irradiating a first laser toward the metal-containing layer from a side opposite to the substrate; irradiating a second laser beam from a side of a second surface of the substrate opposite to the first surface toward a side portion outside the outline of the metal-containing layer; and A portion of the metal-containing layer corresponding to the edge portion is peeled off.

2. The method according to claim 1, in, Using ultrashort pulse laser as the first laser, Here, short pulse laser is used as the second laser.

3. The method according to claim 1, The substrate is made of resin.

4. The method according to claim 1, And the base material has a structure in which the resin layer is provided on a glass substrate.

5. The method according to claim 1, in, When the first laser is irradiated, the profile is formed by forming a groove reaching the resin layer.

6. The method according to claim 1, wherein the base material has a structure in which the resin layer is disposed on a glass substrate, in, The contour is formed by forming a groove reaching the glass substrate when the first laser is irradiated.

7. The method according to claim 1, in, The substrate has a flat plate shape.

8. The method according to claim 1, The substrate has a spherical shape or a cylindrical shape.

9. A ruler comprising: an optically transparent substrate having a resin layer on a first surface thereof; as well as a plurality of conductor patterns, the plurality of conductor patterns being provided on the resin layer and having a structure in which a plurality of metal grids are formed at intervals, Wherein, a dot pattern is formed at intervals in a two-dimensional direction on a region of the resin layer except for the conductor pattern.

10. The scale according to claim 9, And the spot pattern is concavities and convexities formed on the surface of the resin layer.

11. An encoder comprising the scale according to claim 9.

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