WO2013187024A1

WO2013187024A1 - Electronic pen and image display system provided with electronic pen

Info

Publication number: WO2013187024A1
Application number: PCT/JP2013/003558
Authority: WO
Inventors: 一哉古割; 剛桑山; 利治大石
Original assignee: パナソニック株式会社
Priority date: 2012-06-12
Filing date: 2013-06-06
Publication date: 2013-12-19

Abstract

In order to reduce the possibility of breaking a component at the time of replacing the pen tip section of an electronic pen, the electronic pen has: a main body case; a circuit board (91) having a mounting section (92) for having a light receiving element (52) mounted thereon; and the pen tip section, which is hollow, and which has a light taking port at the leading end. The mounting section (92) is covered with the shield cases (94, 97), the circuit board (91) is disposed inside of the main body case such that the mounting section (92) protrudes from the leading end of the main body case, and the mounting section (92) is housed in the hollow of the pen tip section.

Description

Electronic pen and image display system provided with electronic pen

The present disclosure relates to an electronic pen that draws characters and drawings on an image display device, and an image display system including the electronic pen.

Some image display devices have a function that allows handwriting input of characters and drawings using a pen-type pointing device called “electronic pen” or “light pen”.

For example, Patent Document 1 describes a technique for providing a position coordinate detection period in one field only when position coordinates of an electronic pen are detected in an image display device using a plasma display panel. In the position coordinate detection period, light emission for position coordinate detection occurs, and the electronic pen detects the light emission, thereby detecting the position coordinates of the electronic pen.

Patent Document 2 describes an electronic pen that includes an electronic pen body, a pen tip that is pressed against an image display surface during a touch operation, and a connection state detection unit that detects a contact state on the image display surface. Has been.

JP 2001-318765 A JP 2011-145663 A

The electronic pen in the present disclosure includes a main body case, a circuit board having a mounting portion for mounting a light receiving element, and a pen tip portion having a hollow inside and having a light intake port at the tip. Then, the mounting portion is covered with a protective member, and the circuit board is disposed inside the main body case so that the mounting portion protrudes from the tip of the main body case, and the mounting portion is accommodated in the cavity of the pen tip portion.

Further, in the electronic pen of the present disclosure, the protection member may be formed of metal and connected to a fixed potential.

Further, in the electronic pen of the present disclosure, the light receiving element may protrude from the edge of the circuit board, and the protective member may limit the rotation of the light receiving element.

In the electronic pen of the present disclosure, the protection member may be formed of metal, the light receiving element may be a photodiode, and the cathode of the light receiving element and the protection member may be at the same potential.

Further, the electronic pen of the present disclosure may include a pen tip cap that holds the pen tip portion at the tip of the main body case.

An image display system according to the present disclosure includes an image display device in which one field period is configured by a plurality of subfields including a coordinate detection subfield that generates light emission for detecting a position coordinate of an electronic pen on an image display surface; With an electronic pen. Then, the position coordinate of the electronic pen on the image display surface is calculated based on the light emission of the coordinate detection subfield, and drawing is performed based on the calculated position coordinate.

FIG. 1 is a circuit block diagram of an image display system according to Embodiment 1 of the present disclosure. FIG. 2 is an exploded perspective view of the panel of the image display system according to the first embodiment of the present disclosure. FIG. 3 is a waveform diagram of a driving voltage applied to the panel of the image display system according to the first embodiment of the present disclosure. FIG. 4 is a schematic diagram illustrating a position coordinate detection method of the image display system according to Embodiment 1 of the present disclosure. FIG. 5 is a schematic diagram illustrating an example of drawing of the image display system according to the first embodiment of the present disclosure. FIG. 6 is a three-view diagram illustrating an appearance of the electronic pen of the image display system according to the first embodiment of the present disclosure. FIG. 7 is a two-view diagram and a cross-sectional view illustrating the shape of the tip portion of the main body case of the electronic pen according to the first embodiment of the present disclosure. FIG. 8 is a three-view diagram illustrating the shape of the mounting board of the electronic pen according to the first embodiment of the present disclosure. FIG. 9 is a perspective view illustrating the shape of the mounting board of the electronic pen according to the first embodiment of the present disclosure. FIG. 10 is an exploded perspective view illustrating details of the mounting board of the electronic pen according to the first embodiment of the present disclosure. FIG. 11 is a two-view diagram and a cross-sectional view illustrating the shape of the pen tip portion of the electronic pen according to the first embodiment of the present disclosure. FIG. 12 is a two-view diagram and a cross-sectional view illustrating the shape of the pen tip cap of the electronic pen according to the first embodiment of the present disclosure. FIG. 13 is a cross-sectional view illustrating the structure of the tip of the electronic pen according to the first embodiment of the present disclosure. FIG. 14A is an exploded view of the tip portion of the electronic pen according to the first embodiment of the present disclosure. FIG. 14B is an exploded view of the tip portion of the electronic pen according to the first embodiment of the present disclosure. FIG. 14C is an exploded view of the tip portion of the electronic pen according to the first embodiment of the present disclosure. FIG. 15 is a perspective view schematically showing a state in which a pressing force is applied to the light receiving element and the light receiving element rotates. FIG. 16A is a perspective view schematically showing an example of the shape of the protective member in the second embodiment of the present disclosure. FIG. 16B is a diagram schematically illustrating a circuit board to which the protection member according to the second embodiment of the present disclosure is attached. FIG. 17A is a perspective view schematically showing another example of the shape of the protective member in the second embodiment of the present disclosure. FIG. 17B is a diagram schematically illustrating a circuit board to which the protection member according to the second embodiment of the present disclosure is attached. FIG. 18A is a perspective view schematically showing still another example of the shape of the protective member according to Embodiment 2 of the present disclosure. FIG. 18B is a diagram schematically illustrating a circuit board to which the protection member according to the second embodiment of the present disclosure is attached.

Hereinafter, an image display system according to an embodiment of the present disclosure will be described with reference to the drawings.

(Embodiment 1)
FIG. 1 is a circuit block diagram of an image display system 100 according to the first embodiment of the present disclosure.

The image display system 100 includes an image display device 30, a drawing device 40, and a plurality of electronic pens 50. A single electronic pen 50 may be used.

The image display device 30 includes a display device that displays an image and a drive circuit that drives the display device. Hereinafter, an image display apparatus 30 using a plasma display panel (hereinafter abbreviated as “panel”) 10 as a display device will be described as an example, but the display device may be a liquid crystal, an organic EL, or the like.

The image display device 30 includes, as drive circuits, an image signal processing unit 31, a data electrode drive unit 32, a scan electrode drive unit 33, a sustain electrode drive unit 34, and a control unit that controls the operation of each circuit block (see FIG. And a power supply unit (not shown) for supplying power necessary for each circuit block.

The image signal processing unit 31 synthesizes an image signal input from the outside and a drawing signal output from the drawing device 40, or outputs one of them to the data electrode driving unit 32. The data electrode driver 32 generates a drive voltage waveform applied to the data electrode 22, the scan electrode driver 33 generates a drive voltage waveform applied to the scan electrode 12, and the sustain electrode driver 34 applies to the sustain electrode 13. Generate a drive voltage waveform.

FIG. 2 is an exploded perspective view of the panel 10 of the image display system 100 according to the first embodiment of the present disclosure.

The panel 10 is configured such that a front substrate 11 and a rear substrate 21 are arranged to face each other. A plurality of display electrode pairs 14 including scan electrodes 12 and sustain electrodes 13 are formed on the front substrate 11. A plurality of data electrodes 22 are formed on the rear substrate 21, and a phosphor layer 25 is further provided. The discharge space inside the panel 10 is divided into a plurality of sections by partition walls 24, and discharge cells are formed at the intersections between the display electrode pairs 14 and the data electrodes 22. These discharge cells discharge and emit light, whereby an image is displayed in the image display area of the panel 10.

Next, the driving voltage waveform applied to each electrode of the panel 10 will be described. In the present embodiment, a plurality of image display subfields (not shown) for displaying an image and a plurality of coordinate detection subfields for detecting “position coordinates” of the electronic pen 50 in one field period. (Shown in FIG. 3). “Position coordinates” are coordinates (coordinates indicating the position of the electronic pen 50) indicated by the electronic pen 50 in the image display area of the panel 10.

Since the drive voltage waveform in the image display subfield is the same as the conventional drive voltage waveform, the description with reference to the drawings is omitted. The image display subfield is composed of a plurality of subfields having a predetermined luminance weight. An image is displayed on the panel 10 by controlling light emission / non-light emission of each image display subfield for each discharge cell.

FIG. 3 is a waveform diagram of a drive voltage applied to the panel 10 of the image display system according to the first embodiment of the present disclosure. FIG. 3 shows drive voltage waveforms applied to the respective electrodes of the panel 10 in each of the coordinate detection subfields.

The coordinate detection subfield is a generic name for the synchronization detection subfield SFo, the y coordinate detection subfield SFy, and the x coordinate detection subfield SFx. The synchronization detection subfield SFo is a subfield that generates light for the electronic pen 50 to synchronize with the coordinate detection subfield of the image display device 30. The y coordinate detection subfield SFy is a subfield that emits light for detecting the y coordinate of the position coordinates of the electronic pen 50. The x-coordinate detection subfield SFx is a subfield that emits light for detecting the x-coordinate of the position coordinates of the electronic pen 50.

In the synchronization detection subfield SFo, the entire image display surface of the panel 10 is caused to emit light a plurality of times at predetermined time intervals. In this embodiment, four discharges are generated that occur at intervals of time To1, time To2, and time To3.

In the y-coordinate detection subfield SFy, the y-coordinate detection voltage Vdy is applied to the data electrode 22, and y is applied to each scan electrode 12 from the scan electrode 12 in the first row to the scan electrode 12 in the n-th row. Coordinate detection pulses Vay are sequentially applied. Accordingly, the discharge cell rows sequentially emit light one by one from the first discharge cell row to the nth discharge cell row. The “discharge cell row” is an aggregate of discharge cells constituting one row.

Thus, in the y coordinate detection subfield SFy, a horizontal line that moves from the upper end to the lower end of the image display surface is displayed on the panel 10. Therefore, as described later, the electronic pen 50 can detect the y-coordinate of the position coordinates of the electronic pen 50 by receiving the light emission of the discharge cell row and detecting the timing of the light emission. In addition, since the moving speed of the horizontal line is very fast, it looks visually as if the entire image display surface is slightly brightened.

In the x-coordinate detection subfield SFx, an x-coordinate detection voltage Vax is applied to the scanning electrode 12 and one or more data electrodes 22 are provided from the first column data electrode 22 to the m-th column data electrode 22. The x coordinate detection pulse Vdx is sequentially applied to each book. As a result, one or more of the discharge cell columns sequentially emit light from the first discharge cell column to the mth discharge cell column. Note that the “discharge cell column” is an aggregate of discharge cells constituting one column.

Thus, in the x coordinate detection subfield SFx, a vertical line moving from the left end portion to the right end portion of the image display surface is displayed on the panel 10. Therefore, as will be described later, the electronic pen 50 can detect the x coordinate of the position coordinate of the electronic pen 50 by receiving the light emission of the discharge cell array and detecting the timing of the light emission. Since the moving speed of the vertical line is very fast, it looks visually as if the entire image display surface is slightly brighter.

As described above, the image display device 30 forms one field period with a plurality of subfields including a coordinate detection subfield that generates light emission for detecting the position coordinates of the electronic pen 50.

The electronic pen 50 is for inputting characters, drawings and the like on the image display surface of the panel 10 by handwriting. The electronic pen 50 receives light emitted from the panel 10 and outputs position coordinates (x coordinate, y coordinate) of the electronic pen 50. As shown in FIG. 1, the electronic pen 50 includes a drawing switch 51, a light receiving element 52, a synchronization detection unit 54, a coordinate calculation unit 56, and a transmission unit 58.

The drawing switch 51 is attached near the tip of the electronic pen 50, and is turned on when the electronic pen 50 is in contact with the image display surface of the panel 10, and is turned off when the electronic pen 50 is separated from the image display surface.

The light receiving element 52 is attached to the tip of the electronic pen 50, receives light emitted from the panel 10, and outputs a light receiving signal. The light reception signal is output to each of the synchronization detection unit 54 and the coordinate calculation unit 56.

The synchronization detection unit 54 detects a predetermined light emission from the received light signal, creates a coordinate reference signal, and outputs it to the coordinate calculation unit 56. The coordinate reference signal is a signal generated in synchronization with the coordinate detection subfield and is a reference signal for detecting position coordinates.

The coordinate calculation unit 56 calculates the position coordinates (x coordinate, y coordinate) of the electronic pen 50 based on the coordinate reference signal and the light reception signal.

FIG. 4 is a schematic diagram illustrating a position coordinate detection method of the image display system 100 according to Embodiment 1 of the present disclosure. In FIG. 4, the image display area of the panel 10 is indicated by a broken line, but this broken line is not actually displayed on the panel 10.

As described above, in the y-coordinate detection subfield SFy, the horizontal line Ly moving from the upper end portion to the lower end portion of the image display surface is displayed on the image display device 30. Therefore, at the time tyy when the horizontal line Ly passes the coordinates (x, y) of the image display surface indicated by the electronic pen 50, the light receiving element 52 of the electronic pen 50 receives the light emission of the horizontal line Ly. Therefore, as shown in FIG. 3, the light receiving element 52 outputs a light reception signal indicating light reception at time tyy.

Also, in the x-coordinate detection subfield SFx, a vertical line Lx moving from the left end portion to the right end portion of the image display surface is displayed on the image display device 30. Accordingly, at time txx when the vertical line Lx passes through the coordinates (x, y) of the image display surface indicated by the electronic pen 50, the light receiving element 52 of the electronic pen 50 receives the light emission of the vertical line Lx. Therefore, the light receiving element 52 outputs a light reception signal indicating light reception at time txx, as shown in FIG.

The coordinate calculation unit 56 measures the time Tyy shown in FIG. 3 based on the coordinate reference signal and the light reception signal in the y coordinate detection subfield SFy. And y coordinate is calculated | required from this time Tyy. Also, the coordinate calculation unit 56 measures the time Txx shown in FIG. 3 based on the coordinate reference signal and the light reception signal in the x coordinate detection subfield SFx. And x coordinate is calculated | required from this time Txx.

The transmission unit 58 encodes the coordinates (x, y) calculated by the coordinate calculation unit 56 and transmits them to the reception unit 42 wirelessly.

As described above, the electronic pen 50 calculates the position coordinates of the electronic pen 50 based on the light emission of the coordinate detection subfield.

The drawing device 40 creates a drawing signal based on the position coordinates (x, y) of the electronic pen 50. This drawing signal is a signal for displaying characters or drawings drawn by the user on the panel 10 and is substantially the same as the image signal. As illustrated in FIG. 1, the drawing device 40 includes a receiving unit 42 and a drawing unit 46.

The receiving unit 42 receives and decodes a radio signal transmitted from the transmitting unit 58 of the electronic pen 50, converts it into coordinates (x, y), and outputs it to the drawing unit 46.

The drawing unit 46 includes an image memory 47, generates a drawing signal indicating the locus of the electronic pen 50 on the image display surface based on the coordinates (x, y) calculated by the coordinate calculation unit 56 of the electronic pen 50, and Output to the display device 30.

FIG. 5 is a schematic diagram illustrating an example of drawing of the image display system 100 according to the first embodiment of the present disclosure. In FIG. 5, the image display area of the panel 10 is indicated by a broken line, but this broken line is not actually displayed on the panel 10.

The drawing unit 46 writes a pattern of a predetermined color and size (for example, a white circle) in the image memory 47 around the pixel corresponding to the coordinates (x, y) calculated by the coordinate calculation unit 56. When the user moves the tip of the electronic pen 50 in contact with the image display surface of the image display device 30, the coordinates (x, y) calculated by the coordinate calculation unit 56 also move. The drawing unit 46 sequentially writes a predetermined pattern in the image memory 47 around the moving coordinates (x, y). In this way, the drawing unit 46 creates a drawing signal indicating the locus of the electronic pen 50 on the image display surface, as shown in FIG.

Thus, the drawing apparatus 40 creates a drawing signal based on the position coordinates calculated by the electronic pen 50.

Then, the image signal processing unit 31 of the image display device 30 synthesizes the image signal input from the outside and the drawing signal output from the drawing unit 46, and outputs them to the data electrode driving unit 32. As a result, in the image display device 30, an image based on characters or drawings input by handwriting with the electronic pen 50 and an image based on an image signal input from the outside are superimposed and displayed on the panel 10.

Next, the structure of the electronic pen 50 in the present embodiment will be described.

FIG. 6 is a three-view diagram illustrating an appearance of the electronic pen 50 according to the first embodiment of the present disclosure. FIG. 6 shows a plan view, a front view, and a side view of the electronic pen 50.

The casing that forms the external appearance of the electronic pen 50 includes a main body case 60, a pen tip portion 70, and a pen tip cap 80. In the housing of the electronic pen 50, a plurality of mounting boards (not shown) including a mounting board 90 on which the light receiving element 52, the drawing switch 51, and their peripheral circuits are mounted, and a battery ( (Not shown).

The main body case 60 includes a partial side case 60a and a partial side case 60b. On the upper surface of the electronic pen 50, various switches 68 such as a power switch and a display component 69 such as a pilot lamp are provided between the partial side case 60a and the partial side case 60b. The

partial side cases

60a and 60b have a battery case cover 65 that is opened and closed when the battery is replaced.

FIG. 7 is a two-view diagram and a cross-sectional view illustrating the shape of the tip portion of the main body case 60 of the electronic pen 50 according to the first embodiment of the present disclosure. FIG. 7 shows a plan view, a side view, and a plan sectional view of the main body case 60.

A through-hole 61 for exposing the light receiving element 52 (not shown in FIG. 7) from the main body case 60 is provided at the distal end portion of the main body case 60.

Notches

63 and 64 for positioning the pen tip portion 70 are provided around the through hole 61. A screw 62 for screwing the nib cap 80 is engraved around the tip of the main body case 60.

FIG. 8 is a three-view diagram illustrating the shape of the mounting substrate 90 of the electronic pen 50 according to the first embodiment of the present disclosure. FIG. 8 shows a plan view, a front view, and a side view of the mounting substrate 90.

FIG. 9 is a perspective view illustrating the shape of the mounting substrate 90 according to the first embodiment of the present disclosure.

FIG. 10 is an exploded perspective view illustrating details of the mounting substrate 90 according to the first embodiment of the present disclosure.

The mounting board 90 includes a circuit board 91, a drawing switch 51 mounted on the circuit board 91, a light receiving element 52, and a part of peripheral circuits (for example, a synchronization detection unit 54 and a coordinate calculation unit 56). And various electronic components (not shown).

The circuit board 91 has a mounting portion 92 protruding in the direction of the through hole 61 of the main body case 60.

The light receiving element 52 is disposed on the front surface of the circuit board 91 so that the light receiving portion of the light receiving element 52 protrudes further outward from the mounting portion 92 of the circuit board 91, and the electrode terminals of the light receiving element 52 are The circuit board 91 is mounted on the mounting portion 92 by being soldered to a pad 99 provided on the front surface of the mounting portion 92. Thus, the light receiving element 52 protrudes from the edge of the circuit board 91, and the electrode terminal of the light receiving element 52 is mounted on the mounting portion 92 of the circuit board 91.

The drawing switch 51 is mounted in the vicinity of the mounting portion 92 on the circuit board 91.

An insulating sheet 93 is provided on the back side of the circuit board 91 so as to cover various electronic components (not shown) mounted on the circuit board 91, and a shield case 94 as a protective member is attached so as to cover them. It has been.

An insulating sheet 96 is provided on the front (front) surface side of the circuit board 91 so as to cover the electrode terminals of the light receiving element 52 and the pads 99 to which the electrode terminals are soldered, and further protected so as to cover them. A shield case 97 as a member is attached.

The mounting substrate 90 is a state in which the mounting portion 92 and the light receiving element 52 of the circuit board 91 protrude from the through hole 61 to the outside of the main body case 60 (that is, a state where the mounting portion 90 protrudes from the front end of the main body case 60). It is disposed inside the case 60 and is fixed to the main body case 60.

Thus, the mounting substrate 90 is covered with the

shield cases

94 and 97 that are the protective members of the mounting portion 92 of the circuit board 91. The

shield cases

94 and 97, which are protective members, are made of metal and connected to a fixed potential (for example, ground potential) and are grounded in an alternating manner. Therefore, the protective member can reduce electromagnetic noise that jumps into the mounting portion 92 from the outside.

FIG. 11 is a two-view diagram and a cross-sectional view illustrating the shape of the pen tip portion 70 of the electronic pen 50 according to the first embodiment of the present disclosure. FIG. 11 shows a plan view, a side view, and a plan sectional view of the pen tip portion 70.

The nib portion 70 is formed of a material that is relatively soft and has an appropriate rigidity so as not to damage the surface of the panel 10 during use, for example, polyacetal, but the material may be a polyamide, a fluororesin, or the like. .

The pen point portion 70 has a cavity 72 in which the mounting portion 92 and the light receiving element 52 can be accommodated. A light capturing port 71 for capturing light received by the light receiving element 52 is provided at the tip of the pen tip portion 70. The light intake port 71 is a through hole in the present embodiment, but is not limited to the through hole, and may be formed in a window shape with a material that transmits light, for example. Further, the pen tip portion 70 is provided with a positioning claw 73 and a switch push claw 74 for mounting the pen tip portion 70 to the tip portion of the main body case 60.

The pen point portion 70 is disposed at the distal end portion of the main body case 60 with the mounting portion 92 and the light receiving element 52 housed in the cavity 72.

FIG. 12 is a two-view diagram and a cross-sectional view illustrating the shape of the nib cap 80 of the electronic pen 50 according to the first embodiment of the present disclosure. FIG. 12 shows a plan view, a side view, and a plan sectional view of the nib cap 80.

A penetrating hole 81 for penetrating the pen tip portion 70 is provided at the tip of the pen tip cap 80. Further, a screw 82 for screwing the main body case 60 is engraved on the inner wall of the nib cap 80. The pen tip cap 80 is detachably attached to the tip of the main body case 60 with the pen tip portion 70 penetrating the through hole 81 and protruding and held in the tip direction. The pen tip portion 70 is attached by the pen tip cap 80. The main body case 60 is fixed to the tip. Therefore, the nib portion 70 can be replaced relatively easily by removing the nib cap 80 from the main body case 60.

FIG. 13 is a cross-sectional view illustrating the structure of the tip of the electronic pen 50 according to the first embodiment of the present disclosure. In FIG. 13, components (other circuit boards, batteries, etc.) other than the mounting board 90 are omitted.

The mounting substrate 90 is disposed so that the light receiving element 52 and the mounting portion 92 of the circuit substrate 91 protrude from the through hole 61 of the main body case 60 in the distal direction, and is fixed to the main body case 60.

A spring 76 is provided between the pen tip 70 and the light receiving element 52. The nib portion 70 protrudes from the nib cap 80 in the distal end direction, and is further pressed by the spring 76 in the direction of protruding from the nib cap 80 by the elasticity of the spring 76. It is held at the tip. The pen tip portion 70 is slidable in a direction to be pushed into the main body case 60. When the pen tip portion 70 is not pushed into the main body case 60, the drawing switch 51 is “off”.

When the tip of the electronic pen 50 is pressed against the image display surface of the panel 10 and the pen tip 70 is pushed into the main body case 60, the tip of the switch pusher 74 of the pen tip 70 presses the drawing switch 51. The drawing switch 51 is turned on. When the tip of the electronic pen 50 moves away from the image display surface and the pen tip portion 70 returns to its original position due to the elasticity of the spring 76, the drawing switch 51 is turned off.

Next, the procedure for replacing the pen tip unit 70 will be described. As described above, the pen tip portion 70 is formed of a relatively soft material such as polyacetal so that the surface of the panel 10 is not damaged. For this reason, the nib portion 70 is relatively easily worn, and the worn nib portion 70 needs to be replaced.

14A, 14B, and 14C are exploded views of the tip portion of the electronic pen 50 according to the first embodiment of the present disclosure. 14A, 14B, and 14C show a procedure for exchanging the pen tip unit 70. FIG.

To replace the worn nib portion 70, first, the nib cap 80 is removed from the body case 60 as shown in FIG. 14A. As a result, the worn nib portion 70 is exposed.

Next, as shown in FIG. 14B, the worn nib portion 70 is pulled out in the longitudinal direction of the electronic pen 50 and removed from the main body case 60. Thereby, the light receiving element 52 and the spring 76 fitted into the mounting portion 92 of the circuit board 91 are exposed.

At this time, the spring 76 may come off from the light receiving element 52 and the mounting portion 92 of the circuit board 91 in some cases. When the spring 76 comes off, the spring 76 is fitted into the original position.

Next, as shown in FIG. 14C, a new pen tip portion 70 is put on the spring 76. At this time, the pen tip portion 70 is positioned by inserting the positioning claw 73 and switch push claw 74 of the pen tip portion 70 into the cutout portion 63 and the cutout portion 64 of the main body case 60.

Finally, the nib cap 80 is screwed to the main body case 60. The replacement of the pen tip unit 70 is completed by the above procedure.

As shown in FIG. 10, the light receiving element 52 is mounted on the mounting portion 92 with the electrode terminals soldered to the pads 99 provided on the mounting portion 92 of the circuit board 91. As shown in FIG. 14C, the light receiving element 52 and the mounting portion 92 protrude from the main body case 60 to the outside. Therefore, for example, when the pen tip portion 70 is replaced, the user may accidentally touch the light receiving element 52 or the mounting portion 92.

There are electronic components mounted on the mounting portion 92 that are relatively sensitive and vulnerable to static electricity (for example, a light receiving element 52 and an amplifier circuit that amplifies a received light signal). Therefore, when a user touches these electronic components, these electronic components may be damaged by static electricity.

In addition, since these electronic components have relatively high impedance, they are vulnerable to electromagnetic noise and are relatively susceptible to electromagnetic noise. For example, if the S / N ratio of the received light signal is reduced due to the influence of electromagnetic wave noise on the light receiving element 52 and the peripheral circuit of the light receiving element 52, the detection accuracy of the position coordinates is lowered.

However, the electronic pen 50 in the present embodiment forms a pen-shaped main body case 60 having a through-hole 61 at the tip, a circuit board 91 having a mounting portion 92 on which the light receiving element 52 is mounted, and a cavity 72 formed therein. A pen tip portion 70 having a light intake port 71 at the tip portion, and a pen tip cap 80 for holding the pen tip portion 70 at the tip portion of the main body case 60 in a replaceable manner. The mounting portion 92 of the circuit board 91 is covered with a protective member, and the mounting portion 92 is protruded from the through hole 61 of the main body case 60 to hold the circuit board 91 inside the main body case 60. The mounting portion 92 and the light receiving element 52 are housed in the cavity 72 and the pen tip portion 70 is held at the tip portion of the main body case 60.

As described above, since the mounting portion 92 of the circuit board 91 is covered with the shield case 94 and the shield case 97 that are protective members, it is possible to prevent the user from touching the pen tip portion 70 by mistake when the pen tip portion 70 is replaced. Can do. Since the shield case 94 and the shield case 97, which are protective members, are formed of metal and connected to a fixed potential (low voltage side or high voltage side of the power source) and are grounded in an alternating current manner, Electromagnetic wave noise that is received by the manufactured electronic component can be reduced.

(Embodiment 2)
FIG. 15 is a perspective view schematically showing a state where the light receiving element 52 is rotated by applying a pressing force to the light receiving element 52.

As shown in FIG. 10, the light receiving element 52 is supported by the mounting portion 92 by soldering and fixing the tip of the electrode terminal to the pad 99.

Therefore, for example, when the user accidentally touches the light receiving element 52 during replacement of the pen tip portion 70 and a physical pressing force is applied to the light receiving element 52, as shown in FIG. May be bent, and the light receiving element 52 may rotate about the portion fixed to the pad 99 as a fulcrum.

As shown in FIGS. 14A, 14B, and 14C, the light receiving element 52 is arranged so that the optical axis of the light receiving element 52 passes through substantially the center of the light capturing port 71 provided in the pen tip portion 70. It is fixed to the pad 99. Therefore, the light emitted from the panel 10 is received by the light receiving element 52 through the light intake port 71.

However, if the light receiving element 52 rotates and the optical axis of the light receiving element 52 is deviated from the original position, the light receiving element 52 cannot receive the light emitted from the panel 10 normally.

Therefore, in the present embodiment, the protective member is extended until the end of the protective member abuts on the back surface (surface on which the electrode terminal is provided) of the light receiving portion of the light receiving element 52 or until just before the abutting. Thus, the rotation of the light receiving element 52 is limited by the protective member.

FIG. 16A is a perspective view schematically showing an example of the shape of the protective member in the second embodiment of the present disclosure. In FIG. 16A, the shield case 97 shown in the first embodiment is also shown for comparison.

FIG. 16B is a diagram schematically illustrating the circuit board 91 to which the shield case 197 according to the second embodiment of the present disclosure is attached.

As shown in FIG. 16A, in the present embodiment, the shield case 197 that is a protective member is compared with the shield case 97 in the direction in which the light receiving element 52 is installed (the tip direction in the longitudinal direction of the electronic pen 50). Extend. Specifically, as shown in FIG. 16B, the end of the shield case 197 on the side where the light receiving element 52 is installed is brought into contact with the back surface of the light receiving portion of the light receiving element 52 (the surface on which the electrode terminals are provided). Extend until or just before contact.

By making the shield case 197 like this, even if a physical pressing force is applied to the light receiving element 52, the back side of the light receiving element 52 abuts against the end of the shield case 197 as shown in FIG. 16B. Therefore, the rotation of the light receiving element 52 is restricted, and therefore it is possible to prevent the light receiving element 52 from rotating and the optical axis of the light receiving element 52 from deviating from the original position.

It should be noted that the shape of the protective member in the present embodiment is not limited to the shape of the shield case 197 shown in FIGS. 16A and 16B.

FIG. 17A is a perspective view schematically illustrating another example of the shape of the protective member according to Embodiment 2 of the present disclosure. FIG. 17B is a diagram schematically showing the circuit board 91 to which the shield case 297 according to the second embodiment of the present disclosure is attached.

FIG. 18A is a perspective view schematically showing still another example of the shape of the protective member according to Embodiment 2 of the present disclosure. FIG. 18B is a diagram schematically showing the circuit board 91 to which the shield case 397 according to the second embodiment of the present disclosure is attached.

17A and 18A also show the shield case 97 shown in the first embodiment for comparison.

For example, as in the shield case 297 shown in FIGS. 17A and 17B, a part of the end of the shield case 297 on the side where the light receiving element 52 is installed is connected to the back surface of the light receiving portion of the light receiving element 52 (the electrode terminal is provided). It may be extended until it abuts on the surface) or just before it abuts.

Alternatively, as in the shield case 397 shown in FIGS. 18A and 18B, one side of the end of the shield case 397 on the side where the light receiving element 52 is installed is connected to the back surface (electrode terminal is provided) of the light receiving portion of the light receiving element 52. It may extend until it abuts on the surface) or just before it abuts.

As described above, the protective member may be formed in the shape of the shield case 297 shown in FIGS. 17A and 17B or the shield case 397 shown in FIGS. 18A and 18B. The rotation of the light receiving element 52 can be restricted by bringing the back side of the element 52 into contact with the end of the protection member.

For example, if the light receiving element 52 is a photodiode, the region other than the region that captures the light of the photodiode is covered with a metal film, and the metal film and the cathode of the photodiode have the same potential, an electrical short circuit occurs. Therefore, the

shield cases

197, 297, and 397 are set to the same potential as the cathode of the photodiode.

It should be noted that the specific numerical values used in the embodiments are merely examples, and it is desirable to set them to optimal values as appropriate according to the specifications of the electronic pen, the characteristics of the image display device, and the like.

The present disclosure is useful as an image display system including an electronic pen and an electronic pen because the possibility of parts being damaged when the pen tip is replaced can be reduced.

DESCRIPTION OF SYMBOLS 10 Panel 11 Front substrate 12 Scan electrode 13 Sustain electrode 14 Display electrode pair 15, 23 Dielectric layer 16 Protective layer 21 Back substrate 22 Data electrode 24 Partition 25 Phosphor layer 30 Image display device 31 Image signal processing unit 32 Data electrode drive unit DESCRIPTION OF SYMBOLS 33 Scan electrode drive part 34 Sustain electrode drive part 40 Drawing apparatus 42 Reception part 46 Drawing part 47 Image memory 50 Electronic pen 51 Drawing switch 52 Light receiving element 54 Synchronization detection part 56 Coordinate calculation part 58 Transmission part 60

Main body case

60a, 60b Partial

side surface Case

61, 81 Through-

hole

62, 82

Screw

63, 64 Notch 65 Battery case cover 68 Switch 69 Display component 70 Pen tip 71 Light inlet 72 Cavity 73 Positioning claw 74 Switch push claw 76 Spring 80 Pen tip cap 90 Mounting Plate 91 circuit board 92 mounting

portion

93, 96 insulating sheet 94,97,197,297,397 shielding case 99 pad 100 image display system

Claims

A main body case, a circuit board having a mounting portion for mounting the light receiving element, and a pen tip portion having a hollow inside and having a light intake port at the tip,
The mounting portion is covered with a protective member, and the circuit board is disposed in the main body case so that the mounting portion protrudes from the tip of the main body case.
An electronic pen, wherein the mounting portion is housed in a cavity of the pen tip portion.
The electronic pen according to claim 1, wherein the protection member is made of metal and connected to a fixed potential.
The electronic pen according to claim 1, wherein the light receiving element protrudes from an edge of the circuit board, and the protection member restricts rotation of the light receiving element.
4. The electronic pen according to claim 3, wherein the protection member is made of metal, the light receiving element is a photodiode, and the cathode of the light receiving element and the protection member have the same potential.
The electronic pen according to any one of claims 1 to 4, further comprising a pen tip cap that holds the pen tip portion at a tip of the main body case.
An image display device in which one field period is constituted by a plurality of subfields including a coordinate detection subfield for generating light emission for detecting the position coordinates of the electronic pen on the image display surface;
The electronic pen according to claim 1,
An image display system that calculates a position coordinate of the electronic pen on the image display surface based on light emission of the coordinate detection subfield and performs drawing based on the calculated position coordinate.