TW201543314A - Position sensor and sheet-shaped optical waveguide used in same - Google Patents

Abstract

Provided are: a position sensor such that when information such as characters are input by means of an input body such as a pen, unnecessary sections such as the little finger of the hand holding the input body, the base section of said little finger, and the like are not detected; and a sheet-shaped optical waveguide used in same. The position sensor is provided with: a sheet-shaped optical waveguide in which a lattice-shaped core is sandwiched by an under-cladding layer and an over-cladding layer; a light-emitting element connected to one end surface of the core; and a light receiving element connected to the other end surface of the core. The elastic modulus of the core is set to be greater than the elastic moduli of the under-cladding layer and over-cladding layer, when the surface of the sheet-shaped optical waveguide is pressed, the rate of deformation of the cross-section of the core in the pressing direction is less than the rate of deformation of the cross-section of the under-cladding layer and over-cladding layer. The intersecting sections of the lattice-shaped core are such that at least one direction of intersection is split by a gap and thus is a discontinuous intersection.

Description

Position sensor and plate-shaped optical waveguide for the position sensor Field of invention

The present invention relates to a position sensor for optically detecting a pressing position and a plate-shaped optical waveguide for use in the position sensor.

Background of the invention

Heretofore, there has been proposed a position sensor that optically detects a pressing position (see, for example, Patent Document 1). The sensor is formed by arranging a plurality of core materials to be optical paths in the longitudinal and lateral directions, and covering the peripheral portions of the core materials with a cladding layer to form a plate shape, and causing light from the light-emitting elements to be incident. To one end surface of each of the above core materials, light passing through each of the core materials is detected by the light receiving element on the other end surface of each of the core materials. Then, when a part of the surface of the plate-shaped position sensor is pressed with a finger or the like, the core material of the pressing portion can be flattened (the cross-sectional area of the core material in the pressing direction becomes small) due to the pressing portion In the core material, the detection level of light on the light-receiving element is lowered, so that the pressed position can be detected.

On the other hand, as an input device such as an input character, a device having a pressure sensitive touch panel and a display has been proposed (see, for example, Patent Document 2). When the pen is used to input characters or the like on the pressure sensitive touch panel, the pressure sensitive touch panel detects the pressurization position of the pen tip and loses The display is displayed on the display, and the inputted characters and the like are displayed on the display.

Prior technical literature Patent literature

Patent Document 1: Japanese Patent Laid-Open No. Hei 8-234895

Patent Document 2: Japanese Patent Laid-Open Publication No. 2006-172230

Summary of invention

Generally, when a character is written on a paper with a writing instrument such as a pen, the little finger of the hand holding the writing instrument or the finger base portion thereof (small fish) or the like is also in contact with the surface of the paper.

Therefore, when a character or the like is input using a writing instrument such as a pen on the surface of the plate-shaped position sensor of Patent Document 1, it is not only the tip of the pen, but also the little finger or the finger root portion of the hand holding the note device. Since the above-described plate-shaped position sensor is pressed, not only the input characters and the like are detected, but also the above-mentioned little finger or its finger root portion and the like are detected.

In the case where the input device of the above-mentioned Patent Document 2 inputs a character or the like, the pressure sensitive touch panel detects not only the pressed position of the pen tip but also the little finger or finger of the hand holding the note device. The pressing position of the root portion or the like is therefore not only displayed, but also the above-mentioned little finger or its finger root portion and the like are displayed on the display.

The present invention has been made in view of such circumstances, and an object thereof is to provide a position sensor and a plate-shaped optical waveguide for use in the position sensor, which does not input information such as characters by using an input body such as a pen. Will detect An undesired portion such as the little finger or the finger root portion of the hand holding the input body.

In order to achieve the above object, the present invention provides the first position sensor having a plate-shaped optical waveguide, a light-emitting element, and a light-receiving element. The plate-shaped optical waveguide has a plurality of linear core materials forming a lattice shape, a lower cladding layer supporting the core materials, and an upper cladding layer covering the core material, and the light-emitting element is connected to one of the core materials In the end surface, the light-receiving element is connected to the other end surface of the core material, and a part or a part of the lattice-shaped portion formed by the plurality of linear core materials is formed in a state in which at least one of the intersecting directions is broken by the gap. Continuously intersecting, and the elastic modulus of the core material is set to be larger than the elastic modulus of the lower cladding layer and the elastic modulus of the upper cladding layer, and the core of the pressing direction is in a pressed state of the surface of the plate-shaped optical waveguide The deformation rate of the cross section of the material is smaller than the deformation rate of the cross section of the upper cladding layer and the lower cladding layer, and the light of the core material is caused by pressing anywhere on the surface of the position sensor. The amount of change in the amount of the specific pressure is pressed.

Further, the present invention is directed to the second aspect of the present invention, wherein the plate-shaped optical waveguide has a plurality of linear core materials formed in a lattice shape, a lower cladding layer supporting the core materials, and the coating layer. The upper cladding of the core material. In addition, a part or all of the intersecting portions formed in a lattice shape of the plurality of linear core materials are formed so as to be discontinuously intersected in a state in which at least one of the intersecting directions is broken by the gap, and the elastic modulus of the core material is set to More than the elastic modulus of the lower cladding layer and the elastic modulus of the upper cladding layer Big.

In addition, the "deformation rate" in the present invention means the ratio of the thickness of each of the thicknesses in the pressing direction to the thickness of each of the thicknesses before the pressing of the core material, the upper cladding layer, and the lower cladding layer. .

The present inventors have placed a surface of a position sensor that forms a lattice-shaped plate-shaped optical waveguide in a plurality of linear core materials, and does not detect the holding of the input body when information such as characters is input by using an input body such as a pen. The light propagation of the above-mentioned core material of the part of the hand is repeated. In the course of this research, it is not assumed that the core material (the cross-sectional area becomes smaller) is used as the pressure of the hand using the pen tip or the pen holding the hand, but instead, the core material is not crushed by the above pressure (maintaining the cross-section) area). Therefore, the elastic modulus of the core material is set to be larger than the elastic modulus of the lower cladding layer and the elastic modulus of the upper cladding layer. Therefore, the portion of the nib and the portion of the hand cause the upper cladding layer and the lower cladding layer to be deformed to be crushed in the pressing direction, and the core material is bent along the nib or the portion of the hand while maintaining the sectional area as it is. Trapped into the lower cladding. Further, the degree of bending of the core material is a sharp bend in the portion of the pen tip, and a gentle curve in the portion of the hand. As a result, in the core material of the nib portion, leakage (scattering) of light from the core material occurs due to the sharp bending of the core material, and the core material in the hand portion is flattened due to the bending of the core material. Therefore, leakage (scattering) of the above light does not occur. That is to say, on the core material of the pen tip portion, the detection level (light receiving amount) of the light on the light receiving element is lowered, and the detection level is not lowered on the core material of the portion of the hand. It is also found that the position of the nib can be detected from the decrease of the detection level of the light, and the portion of the hand whose detection level is not lowered is the same as the state without being pressed, and will not be detected. Thus, the present invention has been achieved.

In particular, when a part or all of the intersection portions of the lattice-shaped core material formed by the plurality of linear core materials are formed so that at least one of the intersecting directions is discontinuously intersected by the gap, the light can be reduced. Cross loss. The inventors of the present invention have also obtained such knowledge and insights.

The position sensor of the present invention sets the elastic modulus of the core material to be larger than the elastic modulus of the lower cladding layer and the elastic modulus of the upper cladding layer. Therefore, when the surface of the upper cladding layer of the optical waveguide is pressed, the deformation ratio of the cross section of the core material in the pressing direction becomes smaller than the deformation ratio of the cross section of the upper cladding layer and the lower cladding layer, and the pressing can be maintained. The cross-sectional area of the core material in the direction. Further, when an input body such as a pen is used to input information such as characters on the surface of the position sensor, the degree of bending of the core material is along the input body at the pressing portion caused by the front end input portion such as the pen tip. The sharp bend of the front end input portion causes leakage (scattering) of light from the core material, and the bending degree of the core material is gentle along the hand on the pressing portion formed by the portion of the hand holding the input body. The above light leakage (scattering) does not occur. Therefore, it is possible to form a case where the detection level of light on the light receiving element is lowered on the core material pressed by the front end input portion such as the pen tip, and the core material pressed by the hand holding the input body is used. The detection bit criterion does not decrease. Further, it is possible to detect the position of the front end input portion of the pen tip or the like from the lowering of the detection level of the light, and the portion of the hand whose detection level is not lowered is the same as the state of not being pressed, and thus is not detected. To. Further, a part of the lattice shape formed by the above-mentioned core material or even all of the intersection portions The at least one direction that becomes the intersection forms a discontinuous intersection in a state in which the gap is broken, so that the cross loss of light can be reduced. Therefore, the detection sensitivity of the position of the front end input portion such as the pen tip can be improved.

In addition, the plate-shaped optical waveguide of the present invention is a discontinuous intersection in a state in which a part of the lattice shape formed by a plurality of linear core materials or all of the intersection portions are formed so that the at least one direction intersects with the gap is broken. Therefore, the cross loss of light can be reduced. Further, since the plate-shaped optical waveguide of the present invention has the elastic modulus of the core material set to be larger than the elastic modulus of the lower cladding layer and the elastic modulus of the upper cladding layer, the pressing is performed when the surface of the upper cladding layer is pressed. The deformation rate of the cross section of the core material in the direction is smaller than the deformation rate of the cross section of the upper cladding layer and the lower cladding layer, and the cross-sectional area of the core material in the pressing direction can be maintained. From the above facts, it is understood that the plate-shaped optical waveguide of the present invention is effective as the configuration of the position sensor of the present invention.

1‧‧‧Under cladding

2‧‧‧ core material

3‧‧‧Upper coating

4‧‧‧Lighting elements

5‧‧‧Light-receiving components

10‧‧‧ Input body

20‧‧‧ hands

30‧‧‧ plane table

10a‧‧‧ front-end input section

2a‧‧‧ wall

A‧‧‧ position sensor

‧‧‧Width

G‧‧‧ gap

R‧‧‧ radius of curvature

T‧‧‧ thickness

W‧‧‧Light Guide

Fig. 1 is a plan view showing an embodiment of a position sensor of the present invention.

2(a) is a plan view schematically showing an intersection of a lattice-shaped core material in the position sensor, and FIG. 2(b) is a cross-sectional model view showing a cross section of a central portion of the position sensor in an enlarged manner.

3(a) is an enlarged plan model diagram showing a travel route of light in a continuous intersection, and (b) is an enlarged plan model diagram showing a travel route of light in a discontinuous intersection.

4(a) is a cross-sectional model diagram showing a state of the position sensor pressed by the input body, and (b) is a view showing the position sensor pressed by the hand. State profile model.

5(a) to 5(e) are enlarged plan view showing a modification of the intersection of the lattice-shaped core members.

Form for implementing the invention

Next, embodiments of the present invention will be described in detail based on the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a plan view showing an embodiment of a position sensor of the present invention. The position sensor A of the embodiment includes a rectangular plate-shaped optical waveguide W having a lattice-shaped core member 2, and a light-emitting element connected to one end surface of the linear core material 2 constituting the lattice-shaped core member 2. 4. A light-receiving element 5 connected to the other end surface of the linear core material 2. Then, light emitted from the light-emitting element 4 passes through the core material 2 and is received by the light-receiving element 5. In addition, in FIG. 1, the core material 2 is shown by the chain line, and the thickness of the core material 2 is shown by the thickness of a chain line. In addition, in FIG. 1, the number of core materials 2 is abbreviate|omitted and it shows. Moreover, the arrow of Fig. 1 indicates the direction in which light travels.

In this embodiment, each of the intersecting portions of the lattice-shaped core material 2 in the plate-shaped optical waveguide W is as shown in a plan view in Fig. 2(a), and all four intersecting directions are broken by the gap G, and become Discontinuous. The width d of the gap G is set to be greater than 0 (zero) (as long as the gap G is formed), and is usually 20 μm or less. Further, as shown in the cross-sectional view of Fig. 2(b), the plate-shaped optical waveguide W is supported by the plate-shaped lower cladding layer 1 in the lattice-shaped core material 2, and is covered by the plate-like upper cladding layer 3. The state is formed. In this embodiment, the gap G is formed by the material forming the cladding layer 3.

As described above, in the lattice-shaped core member 2, when the intersection portion is discontinuous, the cross-loss loss of light can be reduced. That is, as shown in FIG. 3(a), in the case where all of the four intersecting directions are continuous intersections, attention is paid to one direction of the intersection [upward direction in FIG. 3(a)]. At the time, a part of the light incident on the intersection portion reaches the wall surface 2a of the core material 2 which is orthogonal to the forward core material 2, and penetrates the core material 2 because the reflection angle on the wall surface is large. [Refer to the arrow of the two-dot chain line of Fig. 3 (a)]. The penetration of light like this also occurs in the direction opposite to the above (the downward direction in Fig. 3(a)]. On the other hand, as shown in FIG. 3( b ), when one of the intersecting directions (the upward direction in FIG. 3( b )) is not continuous due to the gap G, the gap G and the core material 2 are formed. The interface, and a portion of the light penetrating the core material 2 in FIG. 3(a) will have a smaller angle of reflection at the interface, so that there will be no penetration, and it will be reflected at the interface and continue to The core material 2 advances (see the arrow of the two-dot chain line of Fig. 3(b)]. The reflection of light like this also occurs in the direction opposite to the opposite side (the downward direction in FIG. 3(b)). Thus, as described above, when the intersection portion is made discontinuous, the cross-loss loss of light can be reduced.

Further, the plate-shaped optical waveguide W is such that the elastic modulus of the core member 2 is set to be larger than the elastic modulus of the lower cladding layer 1 and the elastic modulus of the upper cladding layer 3. Thereby, when the surface of the plate-shaped optical waveguide W is pressed, the deformation rate of the cross section of the core material 2 in the pressing direction is smaller than the deformation rate of the cross section of the upper cladding layer 3 and the lower cladding layer 1.

That is, as shown in the cross-sectional views of FIGS. 4(a) and 4(b), the position sensor A is placed on a flat table 30 such as a table, and is placed on the surface of the position sensor A and the grid. The area corresponding to the core material 2 is used on the hand 20 When the input body 10 such as a pen writes information such as a character and inputs it, the pressing portion caused by the front end input portion 10a such as a pen tip (see FIG. 4(a)) and the little finger of the hand 20 or its finger root portion (small fish) In the cross section in the pressing direction of the pressing portion (see FIG. 4(b)), the upper cladding layer 3 and the lower cladding layer 1 are flattened and deformed, and the core having a large elastic modulus is large. The material 2 is bent along the portion of the front end input portion 10a or the hand 20 to be caught in the lower cladding layer 1 while maintaining the sectional area.

Further, in the pressing portion caused by the front end input portion 10a, as shown in Fig. 4(a), since the front end input portion 10a is pointed, the degree of bending of the core material 2 is more imperfect, and occurs from Leakage (scattering) of light of the core material 2 [refer to the arrow of the two-dot chain line of Fig. 4 (a)]. On the other hand, in the pressing portion caused by the hand 20 holding the input body 10, as shown in FIG. 4(b), since the hand 20 is relatively large and spherical in comparison with the front end input portion 10a, Therefore, the degree of bending of the core material 2 is relatively gentle, and leakage (scattering) of the light (the light does not leak in the core material 2) does not occur (see the arrow of the two-dot chain line of FIG. 4(b)]. Therefore, in the core material 2 pressed by the front end input portion 10a, the detection level of the light on the light receiving element 5 is lowered, and in the core material 2 pressed by the hand 20 holding the input body 10, This detection level will not decrease. Further, the position (coordinate) of the front end input portion 10a can be detected from the decrease in the detection level of the light. Since the portion of the hand 20 that has not been lowered in the detection level is the same as the state in which it is not pressed, it is not detected.

At this time, as described above, since the lattice-shaped intersection portion formed by the core material 2 is formed as a discontinuous intersection, the light cross is reduced. Since the state of the loss is lost, the detection sensitivity of the position of the front end input portion 10a such as the pen tip can be increased.

Further, the input body 10 may press the surface of the position sensor A as described above, and may be not only a writing instrument written on paper by ink or the like, but also a simple writing of ink on paper. The body of the bar. When the pressing is released (the input of the front end input unit 10a or the writing is completed), the lower cladding layer 1, the core material 2, and the upper cladding layer 3 are restored to their original states by the respective restoring forces. [Refer to FIG. 2(b)]. Further, the sinking depth D of the core material 2 with respect to the lower cladding layer 1 is preferably set to a maximum of 2000 μm. When the sinking depth D exceeds 2000 μm, there is a fear that the lower cladding layer 1, the core material 2, and the upper cladding layer 3 cannot be restored to the original state, or the plate-shaped optical waveguide W may be broken.

Here, the elastic modulus of the core material 2, the lower cladding layer 1, and the upper cladding layer 3 will be described in more detail.

The elastic modulus of the core material 2 is preferably in the range of 1 GPa to 10 GPa, and more preferably in the range of 2 GPa to 5 GPa. When the modulus of elasticity of the core material 2 is less than 1 GPa, the cross-sectional area of the core material 2 (the core material 2 is not crushed) by the pressure of the front end input portion 10a sometimes due to the shape of the front end input portion 10a such as the nib. In the case of this, there is a fear that the position of the front end input unit 10a cannot be detected correctly. On the other hand, when the elastic modulus of the core material 2 exceeds 10 GPa, the bending of the core material 2 due to the pressure of the front end input portion 10a does not become a sharp curve along the front end input portion 10a but becomes gentle. The situation of bending. Therefore, leakage (scattering) of light from the core material 2 does not occur, and the detection level of light on the light receiving element 5 does not change. Since it is low, there is a fear that the position of the front end input unit 10a cannot be detected correctly. Further, the size of the core material 2 is set to, for example, a thickness of 5 to 100 μm and a width of 1 to 300 μm.

The elastic modulus of the upper cladding layer 3 is preferably in the range of 0.1 MPa or more and less than 10 GPa, and more preferably in the range of 1 MPa or more and less than 5 GPa. When the elastic modulus of the upper cladding layer 3 is less than 0.1 MPa, it may be too soft, and the shape of the front end input portion 10a such as a pen tip may be damaged under the pressure of the front end input portion 10a, and it may become impossible. Protect the core material 2. On the other hand, when the modulus of elasticity of the upper cladding layer 3 is 10 GPa or more, even if the pressure is applied to the front end input portion 10a or the hand 20, the core material 2 is not crushed and is not formed correctly. The position of the front end input unit 10a is detected. Further, the thickness of the upper cladding layer 3 is set to be, for example, in the range of 1 to 200 μm.

The elastic modulus of the lower cladding layer 1 is preferably in the range of 0.1 MPa to 1 GPa, and more preferably in the range of 1 MPa to 100 MPa. When the modulus of elasticity of the lower cladding layer 1 is less than 0.1 MPa, it is too soft, and it does not return to the original state after being pressed by the front end input portion 10a such as a pen tip, and cannot be continuously performed. On the other hand, when the modulus of elasticity of the lower cladding layer 1 exceeds 1 GPa, even if the pressure transmitted through the front end input portion 10a or the hand 20 does not become flattened, the core material 2 is crushed, and the front end cannot be accurately detected. The position of the input unit 10a is a concern. Further, the thickness of the lower cladding layer 1 is set to, for example, a range of 20 to 2000 μm.

The material for forming the core material 2, the lower cladding layer 1 and the upper cladding layer 3 may be, for example, a photosensitive resin or a thermosetting resin, and may be used. The plate-shaped optical waveguide W is manufactured by a method of forming a material. Further, the refractive index of the core material 2 is set to be larger than the refractive indices of the lower cladding layer 1 and the upper cladding layer 3. Further, the above-described elastic modulus and adjustment of the refractive index can be adjusted by, for example, selecting the type or composition ratio of each type of forming material. Further, a rubber sheet may be used for the lower cladding layer 1, and the core material 2 may be formed in a lattice shape on the rubber sheet.

Further, an elastic layer such as a rubber layer may be provided on the back surface of the lower cladding layer 1. In this case, even if the restoring force of the lower cladding layer 1, the core material 2, and the upper cladding layer 3 is deteriorated, or the lower cladding layer 1 or the like is originally a layer formed of a material having a poor recovery force, It is still possible to use the elastic force of the elastic layer to assist the above-described poor restoring force, and to return to the original state after the pressing by the front end input portion 10a of the input body 10 is released.

Further, as described above, in order to detect only the position of the distal end input portion 10a such as the pen tip, the hand 20 of the input body 10 such as a pen is not detected, and the core material 2 of the pressing portion caused by the distal end input portion 10a is The amount of light leakage (scattering) caused by rapid bending is important. Therefore, for example, a ratio A (=R/T) of the radius of curvature R (unit: μm) of the front end input portion 10a such as a pen tip to the thickness T (unit: μm) of the core material 2 is used, and the core material 2 and the lower package are specified. When the refractive index difference Δ between the cladding layer 1 and the upper cladding layer 3 is Δmax, the maximum value Δmax of the refractive index difference Δ becomes the following formula (1). In other words, when the refractive index difference Δ is larger than the maximum value Δmax, even if the front end input portion 10a is pressed, the amount of light leakage (scattering) is reduced, and the detection position of the light on the light receiving element 5 is small. It is not sufficient to reduce it, so it is difficult to distinguish the position of the front end input portion 10a from the position of the hand 20.

[Number 1] Δmax = 8.0 × 10 ^{-2 -} A × (5.0 × 10 ^-4 ) (1)

On the other hand, the minimum value Δmin of the refractive index difference Δ is expressed by the following formula (2). That is, when the refractive index difference Δ is smaller than the minimum value Δmin, even if the pressed portion is caused by the hand 20, light leakage (scattering) occurs, and the position of the front end input portion 10a and the hand 20 are The difference in location becomes difficult.

[Number 2] Δmin = 1.1 × 10 ^{-2 -} A × (1.0 × 10 ^-4 ) (2)

Therefore, the above refractive index difference Δ is preferably set between the minimum value Δmin and the maximum value Δmax. Here, for example, the radius R (unit: μm) of the front end input portion 10a is in the range of 100 to 1000, and the thickness T (unit: μm) of the core material 2 is in the range of 10 to 100, and When the ratio A is in the range of 1 to 100, the refractive index difference Δ is in the range of 1.0 × 10 ^-3 to 7.95 × 10 ^-2 . Further, when the ratio A exceeds 100, the minimum value Δmin is made 1.0 × 10 ^-3 (fixed).

Further, the position of the front end input unit 10a detected by the position sensor A and the movement trajectory (character or figure) of the front end input unit 10a that is continuous at the position are stored as memories, for example, as electronic data. In the body or the like, it is transmitted to the display and displayed on the display.

In addition, in the above-described embodiment, the intersection of the lattice-shaped core material 2 is discontinuously discontinuous in all four directions intersecting (see FIG. 2(a)). Make other forms of discontinuous intersections. For example, as shown in FIG. 5(a), only one direction of intersection is The gap G is broken and becomes discontinuous, and as shown in Figs. 5(b) and 5(c), the two directions may be crossed [Fig. 5(b) is the two directions facing each other, and Fig. 5(c) is The two adjacent directions are discontinuous, and as shown in FIG. 5(d), the three intersecting directions may be discontinuous. Further, the discontinuous intersection shown in Fig. 2 (a), Figs. 5 (a) to (d), and the continuous intersection in which all of the four directions intersecting are continuous may be obtained (refer to Fig. 5 (e )]] Two or more types of intersecting lattices.

Next, the embodiment will be described together with the comparative example. However, the invention is not limited to the embodiments.

Example

[Forming material of the upper cladding layer]

Component A: 30 parts by weight of epoxy resin (Epogosey PT, manufactured by Yokkaichi Synthetic Co., Ltd.).

Component B: Epoxy resin (manufactured by DAICEL Co., Ltd., EHPE 3150) 70 parts by weight.

Component C: 4 parts by weight of a photoacid generator (manufactured by SAN-APRO Co., Ltd., CPI 200K).

Component D: 100 parts by weight of ethyl lactate (manufactured by Wako Pure Chemical Industries, Ltd.).

The materials for forming the upper cladding layer are prepared by mixing the components A to D.

[Forming material of core material]

Component E: Epoxy resin (manufactured by DAICEL Co., Ltd., EHPE 3150) 80 parts by weight.

Component F: 20 parts by weight of an epoxy resin (YDCN700-10, manufactured by Nippon Steel Chemical Co., Ltd.).

Component G: 1 part by weight of a photoacid generator (SP170, manufactured by ADEKA CORPORATION).

Component H: 50 parts by weight of ethyl lactate (manufactured by Wako Pure Chemical Industries, Ltd.).

The material for forming the core material is prepared by mixing the components E to H.

[Forming material of lower cladding layer]

Component I: 75 parts by weight of epoxy resin (Epogosey PT, manufactured by Yokkaichi Synthetic Co., Ltd.).

Component J: Epoxy resin (manufactured by Mitsubishi Chemical Corporation, JER1007) 25 parts by weight.

Component K: 4 parts by weight of a photoacid generator (manufactured by SAN-APRO Co., Ltd., CPI 200K).

Component L: 50 parts by weight of ethyl lactate (manufactured by Wako Pure Chemical Industries, Ltd.).

The components of I to L are mixed by the components to prepare a material for forming the lower cladding layer.

[Production of plate-shaped optical waveguide]

The upper cladding layer was formed by a spin coating method using the above-mentioned upper cladding layer forming material on the surface of the glass substrate. The upper cladding layer had a thickness of 5 μm, an elastic modulus of 1.2 GPa, and a refractive index of 1.503.

Next, the core material forming material is used on the surface of the upper cladding layer, and a lattice-shaped core material is formed by photolithography. Each of the lattice-shaped intersecting portions is formed such that all of the four intersecting directions are broken by the gap and become discontinuous discontinuous intersections (see FIG. 2( a )). The width of the above gap was made 10 μm. Further, the core material had a thickness of 30 μm, and the core material of the lattice-like portion had a width of 100 μm, a pitch of 600 μm, an elastic modulus of 3 GPa, and a refractive index of 1.523.

Next, the above-mentioned under cladding is used to cover the core material The layer forming material is formed on the surface of the upper cladding layer by spin coating to form a lower cladding layer. The thickness of the lower cladding layer (thickness from the surface of the upper cladding layer) was 200 μm, the modulus of elasticity was 3 MPa, and the refractive index was 1.503.

Then, a double-sided tape (thickness: 25 μm) was adhered to one surface of a PET substrate (thickness: 1 mm). Next, the other adhesive surface of the double-sided tape is adhered to the surface of the lower cladding layer, and in this state, the upper cladding layer is peeled off from the glass substrate.

[Comparative example]

[Forming material of the upper cladding layer]

Component M: Epoxy resin (manufactured by Yokkaichi Synthetic Co., Ltd., Epogosey PT) 40 parts by weight.

Component N: Epoxy resin (manufactured by DAICEL Co., Ltd., 2021P) 60 parts by weight.

Component O: 4 parts by weight of a photoacid generator (SP170, manufactured by ADEKA CORPORATION).

The components of the upper cladding layer are prepared by mixing the components M to O.

[Forming material of core material]

Component P: 30 parts by weight of epoxy resin (Epogosey PT, manufactured by Yokkaichi Synthetic Co., Ltd.).

Component Q: 70 parts by weight of an epoxy resin (EXA-4816, manufactured by DIC Corporation).

Component R: 4 parts by weight of a photoacid generator (SP170, manufactured by ADEKA CORPORATION).

The material for forming the core material is prepared by mixing the components P to R.

[Forming material of lower cladding layer]

Ingredient S: Epoxy resin (made by Yokkaichi Synthetic Co., Ltd., Epogosey PT) 40 Parts by weight.

Component T: 60 parts by weight of an epoxy resin (manufactured by DAICEL Co., Ltd., 2021P).

Component U: 4 parts by weight of a photoacid generator (SP170, manufactured by ADEKA CORPORATION).

The material for forming the lower cladding layer is prepared by mixing the components S~U.

[Production of plate-shaped optical waveguide]

In the same manner as in the above embodiment, a plate-shaped optical waveguide having the same size was produced. However, the modulus of elasticity is 1 GPa for the upper cladding layer, 25 MPa for the core material, and 1 GPa for the lower cladding layer. Further, the refractive index was 1.504 for the upper cladding layer, 1.532 for the core material, and 1.504 for the lower cladding layer.

[Production of position sensor]

A light-emitting element (XH85-S0603-2s, manufactured by Optowell Co., Ltd.) was connected to one end surface of the core material of each of the plate-shaped optical waveguides of the above-described examples and comparative examples, and a light-receiving element was connected to the other end surface of the core material (Japanese-Japanese Hamamatsu Photon) Each of the position sensors of the examples and the comparative examples was produced by Hamamatsu Photonics Co., Ltd., s10226.

[Evaluation of position sensor]

The surface of each of the position sensors described above was pressed with a pen tip (curvature radius of 350 μm) with a load of 1.47 N, and pressed with a human index finger (curvature radius of 1 cm) at a load of 19.6 N. Then, the detection level (light-receiving amount) of the light of the light-receiving element is measured without receiving the load and the condition, and the attenuation rate is calculated according to the following formula (3).

[Number 3]

As a result, in the position sensor of the embodiment, the attenuation rate at the time of pen tip pressing was 80%, and the attenuation rate at the time of index finger pressing was 0%. On the other hand, in the position sensor of the comparative example, the attenuation rate at the time of pen tip pressing was 60%, and the attenuation rate at the time of index finger pressing was 50%.

That is, it can be seen that in the position sensor of the embodiment, since the detection level of the light of the light receiving element is lowered at the time of pressing the pen tip, the position of the pen tip is not detected when the index finger is pressed, so that the position of the pen tip can be detected only. The position is the same as the unpressed state and will not be detected. On the other hand, it can be seen that in the position sensor of the comparative example, the detection level of the light on the light receiving element is reduced to an equal degree regardless of whether the pen tip is pressed or the index finger is pressed, so that it is not only detected. The position of the nib, even the position of the unwanted index finger will be detected.

In addition, even if the intersecting portions in which the intersecting portions of the lattice-shaped core material are intersected in one to three directions become discontinuous discontinuous intersections (see FIGS. 5(a) to (d)), the display and the above-described implementation can be obtained. The result of the same tendency. Further, even if it is provided with discontinuous intersections in which 1 to 4 directions intersecting are discontinuous (see FIG. 2(a), FIGS. 5(a) to (d)), and all four directions of intersection are The results of the same tendency as the above-described embodiment can be obtained even if two or more intersecting lattice patterns in the continuous continuous intersection [see FIG. 5(e)] are obtained.

In the above embodiments, although specific embodiments of the present invention have been shown, the above embodiments are merely illustrative and not limited. By. Various modifications known to those of ordinary skill in the art to which the invention pertains are within the scope of the invention.

Industrial availability

The position sensor of the present invention can be applied to a case where, when a character or the like is input by holding a pen or the like by hand, only the position or movement trajectory of the front end input portion such as a necessary nib is detected, and the unnecessary trajectory is not detected. The position of the hand, etc. Further, the plate-shaped optical waveguide of the present invention can be applied as a configuration of the position sensor described above.

1‧‧‧Under cladding

2‧‧‧ core material

3‧‧‧Upper coating

4‧‧‧Lighting elements

5‧‧‧Light-receiving components

W‧‧‧Light Guide

A‧‧‧ position sensor

Claims (2)

A position sensor is a plate-shaped position sensor including a plate-shaped optical waveguide, a light-emitting element, and a light-receiving element, and the plate-shaped optical waveguide has a plurality of linear core materials forming a lattice shape, and supports the core materials a lower cladding layer, and an upper cladding layer covering the core material, the light emitting element is connected to one end surface of the core material, and the light receiving element is connected to the other end surface of the core material, and the position sensor is characterized in that A part or all of the intersection portions of the lattice-shaped core material formed by the plurality of linear core materials are formed so as to be discontinuously intersected in a state in which at least one of the intersecting directions is broken by the gap, and the elastic modulus of the core material is set. The elastic modulus of the lower cladding layer and the elastic modulus of the upper cladding layer are larger than the elastic modulus of the upper cladding layer, and the deformation ratio of the cross section of the core material in the pressing direction is higher than that of the upper cladding layer. The deformation rate of the cross section of the layer and the lower cladding layer is smaller, and the pressing portion is specified by a change in the amount of light propagation of the core material caused by pressing at any position on the surface of the position sensor. A plate-shaped optical waveguide having a plurality of linear core materials formed in a lattice shape, a lower cladding layer supporting the core materials, and an upper cladding layer covering the core material, wherein the plate-shaped optical waveguide is characterized by A part or all of the intersecting portions formed in a lattice shape of the plurality of linear core materials are formed so as to be discontinuously intersected in a state in which at least one of the intersecting directions is broken by the gap. Further, the elastic modulus of the core material is set to be larger than the elastic modulus of the lower cladding layer and the elastic modulus of the upper cladding layer.