Position detecting device

Abstract

A position detecting device includes a tablet which has a magnetic sheet and two conductor sheets. The magnetic sheet is formed by weaving a group of warp elements (or weft elements) having multiple insulating fibers and a plurality of relatively long magnetic elements disposed among the fibers at predetermined regular spacings and a group of weft elements (or warp elements) having multiple insulating fibers into a plain weave fabric, which is hardened into a sheet-like configuration. Each of the conductor sheets has a plurality of linear conductor elements extending substantially parallel to each other. The two conductor sheets are respectively overlaid on the upper and lower sides of the magnetic sheet so that the conductor elements and the magnetic elements extend orthogonally with respect to each other. The corresponding conductor elements of the upper and lower conductor sheets are connected to from alternate exciting and detecting lines. The device further includes a driving current source for supplying the exciting lines with a cyclic alternating current designating, a position designating magnetic generator for generating a stationary magnetic field, and a position detecting for calculating, from the voltages respectively induced in the detecting lines, coordinate values of the position designated by the position magnetic generator.

What is claimed is: 
     
       1. A position detecting device comprising: a tablet having a magnetic sheet formed by weaving a group of warp elements (or weft elements) composed of a multiplicity of insulating fibers and a plurality of relatively long magnetic elements disposed among said insulating fibers at predetermined regular spacings and a group of weft elements (or weft elements) composed of a multiplicity of insulating fibers into a plain weave fabric, this fabric being hardened into a sheet-like configuration by means of an insulating resin, and two conductor sheets each having a plurality of linear conductor element formed thereon so as to extend substantially parallel to each other, said two conductor sheets being respectively overlaid on the upper and lower sides of said magnetic sheet so that said conductor elements and said magnetic elements extend orthogonally with respect to each other, and the corresponding conductor elements of the upper and lower conductor sheets being connected to each other, thereby alternately forming exciting lines and detecting lines;   a driving current source for supplying said exciting lines with an alternating current of a predetermined cycle;   a position designating magnetic generator for generating a stationary magnetic field; and   a position detecting circuit for obtaining voltages respectively induced in said detecting lines and calculating, from these induced voltages, coordinate values of a position designated by said position designating magnetic generator.   
     
     
       2. A position detecting device according to claim 1, further comprising another magnetic sheet disposed on each of the outer sides of said conductor sheets so that its magnetic elements extend parallel to the magnetic elements of said magnetic sheet interposed between said conductor sheets. 
     
     
       3. A position detecting device according to claim 2, further comprising a shielding sheet made of a non-magnetic metal and disposed on the outer side of said another magnetic sheet. 
     
     
       4. A position detecting device according to claim 1, further comprising a shielding sheet made of a non-magnetic metal and disposed on each of the outer sides of said conductor sheets. 
     
     
       5. A position detecting device comprising: a tablet having two magnetic sheets each formed by weaving a group of warp elements (or weft elements) composed of a multiplicity of insulating fibers and a plurality of relatively long magnetic elements disposed among said insulating fibers at predetermined regular spacings and a group of weft elements (or warp elements) composed of a multiplicity of insulating fibers into a plain weave fabric, this fabric being hardened into a sheet-like configuration by means of an insulating resin, and four conductor sheets each having a plurality of linear conductor elements formed thereon so as to extend substantially parallel to each other, said two magnetic sheets being disposed such that the magnetic elements of one of them extend in a direction X, while the magnetic elements of the other extend in a direction Y, two of said four conductor sheets being respectively disposed on the upper and lower sides of the magnetic sheet the magnetic elements of which extend in the X direction so that the respective conductor elements thereof extend orthogonally with respect to the X direction, the other two of said four conductor sheets being respectively disposed on the upper and lower sides of the magnetic sheet the magnetic elements of which extend in the Y direction so that the respective conductor elements thereof extend orthogonally with respect to the Y direction, and the corresponding conductor elements, extending in the same direction, of each pair of upper and lower conductor sheets being connected together, thereby alternately forming exciting lines and detecting lines for the X direction and exciting lines and detecting lines for the Y direction;   a driving current source for supplying and exciting lines for the X and Y directions with an alternating current of a predetermined cycle;   a position designating magnetic generator for generating a stationary magnetic field; and   a position detecting circuit for obtaining voltages respectively induced in said detecting lines for the X and Y directions and calculating coordinate values of a position designated by said position designating magnetic generator from these induced voltages.   
     
     
       6. A position detecting device according to claim 5, further comprising four other magnetic sheets, two of them being respectively disposed on the outer sides of said conductor sheets the conductor elements of which extend orthogonally with respect to the X direction such that their magnetic elements extend in the X direction, and the other two of said four magnetic sheets being respectively disposed on the outer sides of said conductor sheets the conductor elements of which extend orthogonally with respect to the Y direction such that their magnetic elements extend in the Y direction. 
     
     
       7. A position detecting device according to claim 6 further comprising a shielding sheet made of a non-magnetic metal and disposed on each of the other sides of the uppermost and lowermost magnetic sheets of said four other magnetic sheets. 
     
     
       8. A position detecting device according to claim 5, further comprising a shielding sheet made of a non-magnetic metal and disposed-on each of the outer sides of the uppermost and lowermost conductor sheets of said four conductor sheets. 
     
     
       9. A position detecting device comprising: a tablet having a magnetic sheet formed by weaving a group of warp elements (or weft elements) composed of a multiplicity of insulating fibers and a plurality of relatively long magnetic elements disposed among said insulating fibers at predetermined regular spacings and a group of weft elements (or warp elements) having an arrangement similar to that of said group of warp elements (or weft elements) into a plain weave fabric, this fabric being hardened into a sheet-like configuration by means of an insulating resin, and four conductor sheets each having a plurality of linear conductor elements formed thereon so as to extend substantially parallel to each other, said magnetic sheet being disposed such that the magnetic elements in either said group of warp elements or said group of weft elements extend in a direction X, while those in the other of the two extend in a direction Y, said four conductor sheets being laid on the upper and lower sides of said magnetic sheet in pairs, respectively, such that the conductor elements of one of each pair of conductor sheets extend in the X direction, while the conductor elements of the other extend in the Y direction, and the corresponding conductor elements of the conductor sheets which extend in the same direction being connected together, thereby alternately forming exciting lines and detecting lines for the X direction and exciting lines and detecting lines for the Y direction;   a driving current source for supplying said exciting lines for the X and Y directions with an alternating current of a predetermined cycle;   a position designating magnetic generator for generating a stationary magnetic field, and   a position detecting circuit for obtaining voltages respectively induced in said detecting lines in the X and Y directions and calculating coordinate values of a position designated by said position designating magnetic generator from these induced voltages.   
     
     
       10. A position detecting device according to claim 9, further comprising another magnetic sheet disposed on each of the outer sides of the uppermost and lowermost conductor sheets of said four conductor sheets such that the magnetic elements in either said group of warp elements or said group of weft elements extend in the X direction, with those in the other of the two extend in the Y direction. 
     
     
       11. A position detecting device according to claim 9, further comprising a shielding sheet made of a non-magnetic metal and disposed on each of the outer sides of the uppermost and lowermost conductor sheets of said four. 
     
     
       12. A position detecting device according to claim 10, further comprising a shielding sheet made of a non-magnetic metal and disposed on the outer side of said another magnetic sheet. 
     
     
       13. In a position detecting device for detecting a position on a tablet designated by a position designating magnetic generator, the magnetic generator generating a stationary magnetic field, the detecting device comprising: a coordinate input device with a display, the input device including a back light and a liquid crystal display, the back light and the liquid crystal display superposing over the tablet through a shielding plate made of a non-magnetic metal, the back light being interposed between the liquid crystal display and the shielding plate. .Iadd.   
     
     
       14.  Apparatus for detecting and displaying the position of an implement on a display surface, the implement including a structure interacting with a position detecting AC field derived from the apparatus, comprising a housing, an electronic two-coordinate direction display configured as a plate in the housing, the display including the display surface as an exterior face of the housing, an active light source having a light emitting surface positioned in the housing for illuminating the display surface, a panel positioned in the housing behind the display for detecting the position of the implement on the display surface, the position detecting panel including means for establishing and detecting AC fields in two coordinate directions, the AC fields interacting with the structure of the implement to cause conductors in the position sensor to derive signals indicative of the position of the implement on the display surface, means responsive to the derived signals for activating the display so the position of the implement on the display surface is displayed on the display surface, the display surface and position detecting panel being superposed and lying in different parallel planes. .Iaddend. .Iadd.15. The apparatus of claim 14 wherein the light emitting surface comprises a planar surface positioned behind and superposed with the display so it lies in a plane parallel to the display surface and the position detecting panel. .Iaddend. .Iadd.16. The apparatus of claim 15 wherein the light emitting surface is positioned between and superposed with the panel and the display. .Iaddend. .Iadd.17. The apparatus of claim 15 further including a planar metal shield plate in the housing, the shield plate lying in a plane that is parallel to the planes of the display surface, light emitting surface and position detecting panel. .Iaddend. .Iadd.18. The apparatus of claim 17 wherein the shield plate includes a metal, non-magnetic surface positioned between the position detecting panel and the light emitting surface. .Iaddend. .Iadd.19. In combination, a cordless implement adapted to be positioned on a display surface, the implement including a non-powered structure that interacts with an AC field,   apparatus for detecting and displaying the position of the implement on the display surface, the apparatus including:   a housing,   an electronic two-coordinate direction display configured as a plate in the housing, the display including the display surface as an exterior face of the housing, and   a panel positioned in the housing behind the display for detecting the position of the implement on the display surface, the position sensor including means for establishing AC fields in two coordinate directions and conductors for deriving signals in two coordinate directions in response to an interaction between the established AC fields and the structure of the implement, the AC fields interacting with the structure on the implement to cause the conductors in the panel to derive signals indicative of the position of the implement on the display surface, means responsive to the derived signals for activating the display so the position of the implement on the display surface is displayed on the display surface, the display surface and position detecting panel being superposed and lying in different parallel planes. .Iaddend. .Iadd.20. The combination of claim 12 further including a planar metal shield plate in the housing, the shield plate lying in a plane that is parallel to the planes of the display surface and position detecting panel. .Iaddend. .Iadd.21. The combination of claim 20 wherein the shield plate includes a metal, non-magnetic surface positioned between the position detecting panel and the display. .Iaddend. .Iadd.22. The combination of claim 19 wherein the housing includes an active light source having a light emitting surface positioned in the housing for illuminating the display surface. .Iaddend. .Iadd.23. The combination of claim 22 wherein the light emitting surface is a planar surface positioned behind the display so it lies in a plane parallel to and is superposed with the display surface and the position detecting panel. .Iaddend. .Iadd.24. A tablet for a position detecting device comprising a magnetic sheet, the magnetic sheet including a woven group of warp elements (or weft elements) having a multiplicity of insulating fibers and a plurality of relatively long magnetic elements disposed among said insulating fibers at predetermined regular spacings and a group of weft elements (or warp elements) having a multiplicity of insulating fibers forming a plain weave fabric, the fabric having a sheet-like configuration, and two conductor sheets each having a plurality of linear conductor elements formed thereon so as to extend substantially parallel to each other, said two conductor sheets being respectively overlaid on and electrically insulated from the upper and lower sides of said magnetic sheet so that said conductor elements and said magnetic elements extend orthogonally with respect to each other, and the corresponding conductor elements of the upper and lower conductor sheets being connected to each other, thereby alternately forming exciting lines and detecting lines for the position of an implement adapted to be moved on the tablet and including a structure adapted to interact with a magnetic field derived from the magnetic elements. .Iaddend. .Iadd.25. The tablet of claim 24 further comprising another magnetic sheet disposed on and electrically insulated from each of the outer sides of said conductor sheets so that its magnetic elements extend parallel to the magnetic elements of said magnetic sheet interposed between said conductor sheets. .Iaddend. .Iadd.26. The tablet of claim 25 further comprising a non-magnetic metal shield sheet disposed on the outer side of said another magnetic sheet. .Iaddend. .Iadd.27. The tablet of claim 24 further comprising a non-magnetic metal shield sheet disposed on the outer side of said conductor sheets. .Iaddend. .Iadd.28. A tablet for a position detecting device comprising a two magnetic sheets, each magnetic sheet including a woven group of warp elements (or weft elements) having a multiplicity of insulating fibers and a plurality of relatively long magnetic elements disposed among said insulating fibers at predetermined regular spacings and a group of weft elements (or warp elements) having a multiplicity of insulating fibers forming a plain weave fabric, the fabric having a sheet-like configuration,   and four conductor sheets each having a plurality of linear conductor elements formed thereon so as to extend substantially parallel to each other, said two magnetic sheets being disposed such that the magnetic elements of one of them extend in a direction X, while the magnetic elements of the other extend in a direction Y, two of said four conductor sheets being respectively disposed on and electrically insulated from the upper and lower sides of the magnetic sheet having magnetic elements which extend in the X direction so that the respective conductor elements thereof extend orthogonally with respect to the X direction, the other two of said four conductor sheets being respectively disposed on and electrically insulated from the upper and lower sides of the magnetic sheet having magnetic elements which extend in the Y direction so that the respective conductor elements thereof extend orthogonally with respect to the Y direction; the corresponding conductor elements, extending in the same direction, of each pair of upper and lower conductor sheets being connected together, thereby alternately forming exciting lines and detecting lines for the X direction and exciting lines and detecting lines for the Y direction for the position of an implement adapted to be moved on the tablet and including a structure adapted to interact with a magnetic field derived from the magnetic elements. .Iaddend. .Iadd.29. The tablet of claim 28 further comprising four other magnetic sheets, two of them being respectively disposed on and electrically insulated from the outer sides of said conductor sheets having conductor elements which extend orthogonally with respect to the X direction such that their magnetic elements extend in the X direction, and the other two of said four magnetic sheets being respectively disposed on and electrically insulated from the outer sides of said conductor sheets having conductor elements which extend orthogonally with respect to the y direction such that their magnetic elements extend in the Y direction. .Iaddend. .Iadd.30. The tablet of claim 29 further comprising a shielding sheet made of a non-magnetic metal and disposed on each of the outer sides of the uppermost and lowermost magnetic sheets of said four other magnetic sheets. .Iaddend. .Iadd.31. The tablet of claim 28 further comprising a shielding sheet made of a non-magnetic metal and disposed on and electrically insulated from each of the outer sides of the uppermost and lowermost conductor sheets of said four conductor sheets. .Iaddend.   
     
     
        .Iadd. 2.  A tablet for a position detecting device comprising a magnetic sheet including a woven group of warp elements (or weft elements) having a multiplicity of insulating fibers and a plurality of relatively long magnetic elements disposed among said insulating fibers at predetermined regular spacings and a group of weft elements (or warp elements) having a multiplicity of insulating fibers forming a plain weave fabric, the fabric having a sheet-like configuration, and four conductor sheets each having a plurality of linear conductor elements formed thereon so as to extend substantially parallel to each other, said magnetic sheet being disposed such that the magnetic elements in either said group of warp elements or said group of weft elements extend in a direction X, while those in the other of the two extend in a direction Y, said four conductor sheets lying on and being electrically insulated from the upper and lower sides of said magnetic sheet in pairs, respectively, such that the conductor elements of one of each pair of conductor sheets extend in the X direction, while the conductor elements of the other extend in the Y direction, and the corresponding conductor elements of the conductor sheets which extend in the same direction being connected together, thereby alternately forming exciting lines and detecting lines for the X direction and exciting lines and detecting lines for the Y direction for the position of an implement adapted to be moved on the tablet and including a structure adapted to interact with a magnetic field derived from the magnetic elements. .Iaddend. .Iadd.33. The tablet of claim 32 further comprising another magnetic sheet disposed on and electrically insulated from each of the other sides of the uppermost and lowermost conductor sheets of said four conductor sheets such that the magnetic elements in either said group of warp elements or said group of weft elements extend in the X direction, while those in the other of the two extend in the Y direction. .Iaddend. .Iadd.34. The tablet of 33 further comprising a non-magnetic metal shield sheet disposed on the outer side of said another magnetic sheet. .Iaddend. .Iadd.35. The tablet of claim 32 further comprising a non-magnetic metal shield sheet disposed on the outer side of said uppermost and lowermost conductor sheets. .Iaddend.