Reflection-type display

Abstract

[Problem] To realize height reduction of a reflection-type display which responds to an stylus input of an electromagnetic resonance (EMR) system. [Solution] A reflection-type display according to the present invention includes: a reflection display layer 13 including a plurality of reflection elements C for reflecting light that entered from a cover glass 18 at a set gradation; a backplane 20 provided at a position farther than the reflection display layer 13 when viewed from an operation surface 1a; and a common electrode layer 14 provided between the cover glass 18 and the reflection display layer 13. The backplane 20 has, in the display region, a plurality of pixel electrodes PX arranged in a matrix along the x direction and the y direction, a plurality of data lines DL extended along the y direction, and a plurality of sensor electrodes X1 extended along the y direction. The plurality of sensor electrodes X1 are used for detecting the position of a pen P within the operation surface 1a by generating an electromagnetic resonance action with an inductor in the pen P.

Description

Reflective Display

[0001] The present invention relates to a reflective display, and more particularly to a reflective display that supports electromagnetic induction (EMR) pen input.

[0002] Electronic paper is a type of reflective display that displays images using external light. Patent Documents 1 and 2 and Non-Patent Document 1 disclose examples of the structure of electronic paper. As shown in these documents, electronic paper has a structure in which a light-reflecting layer containing reflective elements such as microcapsules is sandwiched between pixel electrodes and a common electrode. The pixel electrodes are disposed on the upper surface of a backplane that also contains pixel transistors, gate lines, data lines, etc.

[0003] JP 2015-165570 A U.S. Pat. No. 8,749,476

[0004] S. E. Burns and 21 others, “A scalable manufacturing process for flexible active-matrix e-paper displays”, Journal of the Society for Information Display, July 2005

[0005] The inventors of the present application are considering making a reflective display compatible with electromagnetic induction (EMR) pen input. However, this would require a position detection sensor to be placed below the backplane of the reflective display (on the side farther from the display surface), which would increase the overall thickness, and therefore improvements were needed.

[0006] Therefore, one object of the present invention is to provide a reflective display that can be made low-profile while still being compatible with electromagnetic induction (EMR) pen input.

[0007] A reflective display according to one aspect of the present invention includes a cover layer including an operation surface on which a position indicator having an inductor is operated, a reflective display layer including a plurality of reflective elements that each reflect light incident from the cover layer at a set gradation, a backplane provided at a position farther than the reflective display layer as viewed from the operation surface, and a common electrode layer including a common electrode provided between the cover layer and the reflective display layer, wherein the backplane has, within a display area that overlaps with the plurality of reflective elements in a planar view, a plurality of pixel electrodes arranged in a matrix along a first direction and a second direction intersecting the first direction, a plurality of data lines each extending along the first direction, and a plurality of first electromagnetic induction sensor electrodes each extending along the first direction, wherein the plurality of first electromagnetic induction sensor electrodes are used to detect the position of the position indicator within the operation surface by generating electromagnetic induction between the inductor and the plurality of first electromagnetic induction sensor electrodes.

[0008] A reflective display according to another aspect of the present invention includes a cover layer including an operation surface on which a position indicator having an inductor is operated, a reflective display layer including a plurality of reflective elements that each reflect light incident from the cover layer at a set gradation, a backplane provided at a position farther from the reflective display layer as viewed from the operation surface, and a common electrode provided between the cover layer and the reflective display layer, wherein the backplane has, within a display area that overlaps with the plurality of reflective elements in a planar view, a plurality of pixel electrodes arranged in a matrix along a first direction and a second direction intersecting the first direction, a plurality of gate lines each extending along the second direction, and a plurality of second electromagnetic induction sensor electrodes each extending along the second direction, wherein the plurality of second electromagnetic induction sensor electrodes are used to detect the position of the position indicator on the operation surface by generating electromagnetic induction between the inductor and the plurality of second electromagnetic induction sensor electrodes.

[0009] According to yet another aspect of the present invention, there is provided a reflective display including: a cover layer including an operation surface on which a position indicator having an inductor is operated; a reflective display layer including a plurality of reflective elements that each reflect light incident from the cover layer at a set gradation; a backplane provided at a position farther from the reflective display layer as viewed from the operation surface; and a common electrode provided between the cover layer and the reflective display layer, wherein the backplane has, within a display area that overlaps with the plurality of reflective elements in a planar view, a plurality of pixel electrodes arranged in a matrix along a first direction and a second direction intersecting the first direction, and a plurality of linear conductors each extending along the first direction, wherein the plurality of linear conductors are used as either a plurality of data lines used to supply data signals to the pixel electrodes in a time-division manner, or a plurality of first electromagnetic induction sensor electrodes used to detect the position of the position indicator within the operation surface by generating electromagnetic induction between the inductor and the pixel electrodes.

[0010] According to the present invention, at least one of a plurality of first electromagnetic induction sensor electrodes and a plurality of second electromagnetic induction sensor electrodes is provided within a backplane, making it possible to achieve a low-profile reflective display that supports electromagnetic induction (EMR) pen input.

[0011] 11 is a diagram showing the configuration of a computer 1 according to a first embodiment of the present invention. It is a diagram showing the layer structure of a reflective display 2. It is a circuit diagram of the reflective display 2. It is a diagram showing the positional relationship of various wirings included in the reflective display 2. It is a diagram explaining the processing performed by the sensor controller 4 to detect the position of the pen P using the sensor electrodes X1, Y1. It is a diagram showing the planar structure of a portion of a circuit layer 11 corresponding to the circuit diagram of FIG. 3. It is a schematic cross-sectional view of a backplane 20 corresponding to line A-A shown in FIG. 6. It is a diagram showing the planar structure of a portion of a circuit layer 11 included in a computer 1 according to a second embodiment of the present invention corresponding to the circuit diagram of FIG. 3. It is a schematic cross-sectional view of a backplane 20 corresponding to line B-B shown in FIG. 8. It is a diagram showing the positional relationship of various wirings included in a reflective display 2 according to a second embodiment of the present invention. It is a diagram showing the planar structure of a portion of a circuit layer 11 included in a computer 1 according to a third embodiment of the present invention corresponding to the circuit diagram of FIG. 3. It is a schematic cross-sectional view of a backplane 20 corresponding to line C-C shown in FIG. It is a diagram showing the positional relationship of various wirings included in a reflective display 2 according to a fourth embodiment of the present invention. 14A and 14B are diagrams illustrating the planar structure of a portion of a circuit layer 11 included in a computer 1 according to a fourth embodiment of the present invention, the portion corresponding to the circuit diagram of FIG. 3; FIG. 14B is a diagram illustrating a schematic cross-sectional view of a backplane 20 corresponding to line D-D shown in FIG. 14; FIG. 14C is a diagram illustrating the positional relationship of various wiring included in a reflective display 2 according to a fifth embodiment of the present invention; (a) and (b) are diagrams illustrating the processing performed by a sensor controller 4 according to a fifth embodiment of the present invention to detect the position of a pen P using sensor electrodes X1 and Y1; (a) and (b) are diagrams illustrating the processing performed by a sensor controller 4 according to a first modified example of the fifth embodiment of the present invention; (a) and (b) are diagrams illustrating the processing performed by a sensor controller 4 according to a second modified example of the fifth embodiment of the present invention; FIG. 14C is a diagram illustrating an example of the layer structure of a reflective display 2 when sensor electrodes X1 and Y1 are arranged in a layer other than the circuit layer 11; and (b) is a diagram illustrating an example of the layer structure of a reflective display 2 when sensor electrodes X1 and Y1 are arranged in a layer other than the circuit layer 11.10 is a diagram showing the layer structure of the reflective display 2 when both sensor electrodes X1 and Y1 are used to receive a reception signal Rx. FIG.

[0012] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0013] 1 is a diagram showing the configuration of a computer 1 according to a first embodiment of the present invention. As shown in the figure, the computer 1 according to this embodiment is configured to include a reflective display 2, a host processor 3, and a sensor controller 4.

[0014] 2 is a diagram showing the layer structure of the reflective display 2. As shown in the figure, the reflective display 2 is composed of a substrate 10, a circuit layer 11, a pixel electrode layer 12, a reflective display layer 13, a common electrode layer 14, an adhesive layer 15, a touch sensor 16, an adhesive layer 17, and a cover glass 18 (cover layer). Of these, the substrate 10, the circuit layer 11, and the pixel electrode layer 12 constitute a backplane 20 of the reflective display 2. The surface of the cover glass 18 is the display surface of the reflective display 2 and also constitutes an operation surface 1a for input by a pen P (position indicator) (pen input) and input by a finger F (touch input). Note that FIG. 1 shows only a part of the layer structure shown in FIG. 2.

[0015] As will be described in detail later, a plurality of gate lines GL, a plurality of data lines DL, a plurality of common potential lines CL, and a plurality of sensor electrodes X1 and Y1 are provided on the circuit layer 11. Furthermore, a plurality of pixel electrodes PX are provided on the pixel electrode layer 12, one or more common potential lines CL (common electrodes) are provided on the common electrode layer 14, and sensor electrodes X2 and Y2 are provided on the touch sensor 16.

[0016] Each of the plurality of sensor electrodes X1, Y1 is an electromagnetic induction sensor electrode used for detecting the position of the pen P by an electromagnetic induction (EMR) method, and serves to generate electromagnetic induction between itself and an inductor that constitutes a resonant circuit provided within the pen P. The sensor electrodes X2, Y2 are electric field sensor electrodes used for detecting the position of the finger F by a capacitance method. A predetermined common potential (e.g., ground potential) is supplied from the host processor 3 to the common potential lines CL in the circuit layer 11 and the common potential lines CL, including the common potential line CL in the common electrode layer 14. The common potential line CL in the common electrode layer 14 and the sensor electrodes X2, Y2 are made of a transparent conductive film such as indium tin oxide (ITO) so as not to interfere with the display of the reflective display 2.

[0017] The pixel electrodes PX included in the pixel electrode layer 12 are arranged in a matrix along the x direction and the y direction (direction intersecting the x direction). A plurality of reflective elements C are arranged in the reflective display layer 13. Each reflective element C reflects light incident from the cover glass 18 at a gradation set by the potential of the nearest pixel electrode PX. In one example, the reflective display 2 is electrophoretic electronic paper, and in this case, the reflective elements C are formed by spherical microcapsules as shown in the figure. The reflective display 2 can also be formed by electronic powder electronic paper or a reflective liquid crystal display.

[0018] When the reflective display 2 is an electrophoretic electronic paper, the reflective element C contains oil, a plurality of white pigment elements, and a plurality of black pigment elements. These white pigment elements and black pigment elements are pre-charged, respectively, and are configured to be able to migrate within the oil. When a potential is applied to a pixel electrode PX, an amount of white pigment elements or black pigment elements corresponding to the potential migrates toward the operation surface 1a within the reflective element C near that pixel electrode PX. As a result of this migration, a black and white display is realized with a gradation (set gradation) according to the potential applied to the pixel electrode PX. Although not shown, color display is also possible by using a color filter.

[0019] Returning to FIG. 1 , a rectangular area A1 represents the display area of ​​the reflective display 2 (an area overlapping with the plurality of reflective elements C in the reflective display layer 13 in a planar view). Outside the display area A1 is a bezel area A2. As shown in FIG. 1 , a plurality of wirings SL and a terminal area TA including a plurality of terminals are arranged within the bezel area A2. Of these, the plurality of wirings SL are provided to connect wirings and electrodes arranged within the circuit layer 11, the common electrode layer 14, and the touch sensor 16 to terminals within the terminal area TA. To avoid cluttering the drawing, FIG. 1 schematically illustrates only a portion of the plurality of wirings SL actually provided in the reflective display 2. Each terminal within the terminal area TA is connected to the host processor 3 or the sensor controller 4 via wiring provided outside the reflective display 2.

[0020] Fig. 3 is a circuit diagram of the reflective display 2. Fig. 4 is a diagram showing the positional relationship of various wirings included in the reflective display 2. Fig. 3 shows a circuit for four pixel electrodes PX, but in reality, more pixel electrodes PX are provided. Fig. 4 also shows 12 gate lines GL, 12 data lines DL, 12 common potential lines CL, 8 sensor electrodes X1, and 6 sensor electrodes Y1, but in reality, more wirings are provided. This also applies to Figs. 10, 13, and 16 to 19 shown below.

[0021] As shown in Fig. 4, the gate lines GL and the sensor electrodes Y1 each extend along the x direction. As shown in Fig. 3, the gate lines GL are provided for each row of pixel electrodes PX, and the sensor electrodes Y1 are provided at a ratio of one for every several rows of pixel electrodes PX. Therefore, the number of gate lines GL is equal to the number of rows of pixel electrodes PX, while the number of sensor electrodes Y1 is smaller than the number of rows of pixel electrodes PX. More specifically, it is preferable that the pitch of the gate lines GL be several hundred microns and the pitch of the sensor electrodes Y1 be several millimeters.

[0022] The data lines DL, common potential lines CL, and sensor electrodes X1 each extend in the y direction as shown in Fig. 4. As shown in Fig. 3, the data lines DL and common potential lines CL are each provided for each column of pixel electrodes PX, and one sensor electrode X1 is provided for every several columns of pixel electrodes PX. Therefore, the number of data lines DL and common potential lines CL matches the number of columns of pixel electrodes PX, while the number of sensor electrodes X1 is smaller than the number of columns of pixel electrodes PX. More specifically, it is preferable that the pitch between the data lines DL and common potential lines CL be several hundred microns, and the pitch between the sensor electrodes X1 be several millimeters.

[0023] As shown in Fig. 4, the multiple sensor electrodes X1 are connected to each other two at a time from one end in the x direction by a base electrode BE connected to the end farthest from the terminal area TA (see Fig. 1). The base electrodes BE are disposed within the bezel area A2 in plan view. This connection is made in order to form a loop coil using the two sensor electrodes X1 for receiving an alternating magnetic field emitted from an inductor in the pen P. The end of each sensor electrode X1 closest to the terminal area TA is connected to the sensor controller 4 via a wiring SL.

[0024] On the other hand, both ends of each sensor electrode Y1 are connected to the sensor controller 4 via wiring SL. On the other hand, each gate line GL is alternately connected to the host processor 3 via wiring SL at one end or the other end when viewed in the y direction. Furthermore, each data line DL and each common potential line CL is connected to the host processor 3 via wiring SL at the end closer to the terminal area TA.

[0025] 5 is a diagram illustrating the process performed by the sensor controller 4 to detect the position of the pen P using the sensor electrodes X1 and Y1. In this process, the sensor controller 4 is configured to select the plurality of sensor electrodes Y1 one by one in sequence, excluding two sensor electrodes Y1 from each end in the y direction, and each time select the plurality of loop coils one by one in sequence, excluding one loop coil each from each end in the x direction (the loop coil formed by two sensor electrodes X1; the same applies below).

[0026] As shown in FIG. 5, the sensor controller 4 supplies an AC current i to one end of each of the two sensor electrodes Y1 adjacent to one side of the selected sensor electrode Y1. Ａ and apply an AC current i to one end of each of the two adjacent sensor electrodes Y1 on the other side. Ｂ and the alternating current i Ａ is a current that oscillates with a constant frequency and phase, and the AC current i Ｂ is the AC current i Ａ A typical AC current i Ａ , i Ｂ is a sine wave signal as shown in the figure, but may be a square wave signal. Ａ , i Ｂ The other end of each of the four sensor electrodes Y1 that supply the current is connected to a ground terminal. Note that instead of connecting to a ground terminal, the other ends of the sensor electrodes Y1 may be connected to each other. When the sensor controller 4 performs this operation, a change in magnetic flux occurs above the selected sensor electrode Y1. When the inductor of the pen P enters the changing magnetic flux (alternating magnetic field), electromagnetic induction occurs between the sensor electrode Y1 and the inductor, causing a change in current in the inductor. As a result, an alternating magnetic field is emitted from the pen P, and an electromotive force is generated in the sensor electrode X1 located nearby.

[0027] The sensor controller 4 has a differential amplifier 4a, and is configured so that a selected loop coil and the loop coils on both sides of it are connected in series between two input terminals of the differential amplifier 4a. When an electromotive force is generated in the sensor electrode X1 by the alternating magnetic field emitted by the pen P, a current is generated in the corresponding loop coil and is supplied to the sensor controller 4 via the differential amplifier 4a. The sensor controller 4 applies an AC current i to the sensor electrode Y1 for a predetermined time. Ａ , i Ｂ The current supplied from the differential amplifier 4a immediately after the loop coil 4 is supplied is acquired as a reception signal Rx from the pen P corresponding to each loop coil.

[0028] Through the above processing, the sensor controller 4 acquires the reception signals Rx from each loop coil for each sensor electrode Y1. The sensor controller 4 derives the distribution of the signal strengths of the acquired reception signals Rx on the operation surface 1a, and derives the position of the pen P based on the distribution.

[0029] In FIG. 5, the sensor electrode Y1 is supplied with an AC current i Ａ , i Ｂ The example has been described in which an AC current i is supplied to the sensor electrode X1 and a reception signal Rx is received by the sensor electrode X1. Ａ , i Ｂ In this case, the base electrode BE is disposed on one end or the other end of the sensor electrode Y1, so that each sensor electrode Y1 is used as a loop coil, and one end of each sensor electrode X1 (the end farther from the terminal area TA) is connected in advance to a ground terminal or connected to each other.

[0030] Returning to FIG. 3 , the display operation of the reflective display 2 will be described. As shown in FIG. 3 , the reflective display 2 is configured with a pixel transistor 50 and a storage capacitor 51 for each pixel electrode PX. The control electrode of the pixel transistor 50 is connected to the corresponding gate line GL, one controlled electrode is connected to the corresponding data line DL, and the other controlled electrode is connected to the corresponding pixel electrode PX. Furthermore, one electrode of the storage capacitor 51 is connected to the corresponding pixel electrode PX, and the other electrode is connected to the corresponding common potential line CL. With this configuration, when the host processor 3 activates a certain gate line GL, a series of pixel transistors 50 connected to that gate line GL is turned on, and the corresponding series of pixel electrodes PX is connected to the corresponding data line DL. This allows the host processor 3 to control the set grayscale of each pixel by controlling the potential of the data line DL. Furthermore, while the pixel transistor 50 is on, the potential of the data line DL is also applied to the storage capacitor 51, charging it. The charge stored in the storage capacitor 51 by this charging is maintained even after the pixel transistor 50 is turned off, so the display state of each pixel is maintained even while the corresponding gate line GL is inactive.

[0031] FIG. 6 is a diagram schematically illustrating the planar structure of a portion of the circuit layer 11 corresponding to the circuit diagram in FIG. 3, and FIG. 7 is a schematic cross-sectional view of the backplane 20 corresponding to line A-A shown in FIG. 6. Since both FIGS. 6 and 7 are schematic diagrams for understanding the structure, the configurations shown in each diagram do not necessarily match. In order to facilitate understanding of the structure, FIG. 7 also illustrates a portion of the reflective element C in the reflective display layer 13. These points also apply to FIGS. 8, 9, 11, 12, 14, and 15 shown below. Below, the structure within the backplane 20 will be described in detail with reference to FIGS. 6 and 7.

[0032] As shown in FIGS. 6 and 7, the circuit layer 11 is configured to include a gate conductor film 41 , a gate insulating film 42 , a semiconductor film 43 , a source / drain conductor film 44 , a passivation film 31 , and an overcoat film 32 .

[0033] The gate conductor film 41 is a metal film formed on the upper surface of the substrate 10, and constitutes the gate line GL, the control electrode of the pixel transistor 50, one electrode of the storage capacitor 51, and the sensor electrode Y1. The portion of the gate conductor film 41 that constitutes the sensor electrode Y1 extends along the gate line GL.

[0034] The gate insulating film 42 is an insulating film formed so as to cover the upper surface of the gate conductor film 41, and constitutes the gate insulating film of the pixel transistor 50 and a dielectric disposed between the electrodes of the storage capacitor 51. The gate insulating film 42 is also configured to have a contact hole 42h above a portion that is an extension of a portion of the gate conductor film 41 that constitutes one electrode of the storage capacitor 51.

[0035] The semiconductor film 43 is an amorphous silicon film formed on the upper surface of the gate insulating film 42 at a position overlapping the control electrode of the pixel transistor 50 in a plan view, and constitutes a channel layer of the pixel transistor 50 .

[0036] The source / drain conductive film 44 is a metal film formed on the upper surfaces of the gate insulating film 42 and the semiconductor film 43, and constitutes the data line DL, the common potential line CL, the other electrode of the storage capacitor 51, and the sensor electrode X1, as well as one and other controlled electrodes of the pixel transistor 50. The portion of the source / drain conductive film 44 that constitutes the sensor electrode X1 extends between the data line DL and the storage capacitor 51 that are adjacent in the x direction. The source / drain conductive film 44 also serves as internal wiring that connects the other controlled electrode of the pixel transistor 50 to one electrode of the storage capacitor 51 and the pixel electrode PX. The source / drain conductive film 44 is connected to the gate conductive film 41, which serves as one electrode of the storage capacitor 51, via the contact hole 42h described above.

[0037] The passivation film 31 is an insulating film for protecting the pixel transistor 50 and the storage capacitor 51 from dust and moisture, and is formed to cover the entire surface above the source / drain conductor film 44. In the passivation film 31, a contact hole 31h having a smaller diameter than the contact hole 42h is provided in the center of the contact hole 42h.

[0038] The overcoat film 32 is also a protective insulating film and is formed on the upper side of the passivation film 31 so as to cover the entire surface. In the overcoat film 32, a contact hole 32h having a larger diameter than the contact hole 42h is provided at the same position as the contact hole 31h. While the diameter of each reflective element C is about 25 μm, the diameter of the contact hole 32h is usually 10 μm or less.

[0039] The pixel electrodes PX are formed of a conductive film formed on the upper surface of the overcoat film 32. Unlike the common potential lines CL in the common electrode layer 14, the pixel electrodes PX do not need to be transparent. However, they are typically formed of indium tin oxide (ITO), the same material as the common potential lines CL in the common electrode layer 14. This is to prevent the pixel electrodes PX from oxidizing during the manufacturing process of the reflective display 2. Specifically, the backplane 20 and the layers above the reflective display layer 13 (front plane) are typically fabricated in separate processes, and then the two planes are bonded together. During this process, the pixel electrodes PX are temporarily exposed to air. If the pixel electrodes PX were made of a metal film such as aluminum, they would quickly oxidize. Forming the pixel electrodes PX using indium tin oxide (ITO) makes it possible to avoid such oxidation.

[0040] As described above, according to the computer 1 of this embodiment, the plurality of sensor electrodes X1, Y1 used for detecting the position of the pen P by the electromagnetic induction (EMR) method are provided inside the backplane 20 of the reflective display 2, so that it is possible to realize a low-profile reflective display 2 that is compatible with pen input by the electromagnetic induction (EMR) method.

[0041] Next, a computer 1 according to a second embodiment of the present invention will be described. The computer 1 according to this embodiment differs from the computer 1 according to the first embodiment in that the data line DL is used as the sensor electrode X1, rather than providing the sensor electrode X1 separately from the data line DL. In other respects, the computer 1 according to this embodiment is similar to the computer 1 according to the first embodiment, and the following description will focus on the differences from the computer 1 according to the first embodiment.

[0042] Fig. 8 is a diagram showing the planar structure of a portion of the circuit layer 11 included in the computer 1 according to the present embodiment, which corresponds to the circuit diagram of Fig. 3, and Fig. 9 is a schematic cross-sectional view of the backplane 20 corresponding to the line B-B shown in Fig. 8. As shown in Fig. 8 and Fig. 9, the circuit layer 11 according to the present embodiment differs from the circuit layer 11 according to the first embodiment in that it does not have a portion of the source-drain conductor film 44 that constitutes the sensor electrode X1.

[0043] 10 is a diagram showing the positional relationship of various wirings included in the reflective display 2 according to this embodiment. As shown in the figure, the reflective display 2 according to this embodiment is configured to have switch groups 60 and 61, each of which is made up of a plurality of switch elements.

[0044] The switch group 60 is a group of switches made up of a plurality of switch elements provided for each data line DL. Each switch element is provided midway along the wiring SL and is configured as a single-pole, double-throw switch having a common terminal connected to the end of the corresponding data line DL on the terminal area TA side, one selection terminal connected to the host processor 3, and the other selection terminal connected to the sensor controller 4.

[0045] The switch group 61 is a switch group consisting of a plurality of switch elements provided for each pair of adjacent data lines DL. Each switch element is provided midway on a base electrode BE connected to the end of each data line DL farther from the terminal area TA, and is configured as a single-pole, single-throw switch having one terminal connected to one of the corresponding two data lines DL and the other terminal connected to the other of the corresponding two data lines DL.

[0046] The sensor controller 4 according to this embodiment also uses the linear conductors constituting the data lines DL as sensor electrodes X1 in a time-division manner. Specifically, the sensor controller 4 first sets each switch element constituting the switch group 60 to the host processor 3 side and turns off each switch element constituting the switch group 61 when the host processor 3 drives the data lines DL. This allows the host processor 3 to drive the data lines DL as usual. Meanwhile, during a blank period when the host processor 3 does not drive the data lines DL, the sensor controller 4 sets each switch element constituting the switch group 60 to the sensor controller 4 side and turns on each switch element constituting the switch group 61. This allows a loop coil to be formed by the linear conductors constituting the data lines DL, enabling the sensor controller 4 to obtain a received signal Rx from the pen P via the sensor electrode X1, as in the first embodiment.

[0047] As described above, in the computer 1 according to this embodiment, the plurality of sensor electrodes X1, Y1 used for detecting the position of the pen P by the electromagnetic induction (EMR) method are provided in the backplane 20 of the reflective display 2, so that it is possible to realize a low-profile reflective display 2 that is compatible with pen input by the electromagnetic induction (EMR) method.

[0048] Furthermore, according to the computer 1 of this embodiment, the linear conductors that make up the data lines DL are also used as the sensor electrodes X1, so that it is possible to reduce the number of wires in the display area A1.

[0049] Next, a computer 1 according to a third embodiment of the present invention will be described. The computer 1 according to this embodiment differs from the computer 1 according to the first embodiment in the structure of the storage capacitor 51. In other respects, the computer 1 according to this embodiment is similar to the computer 1 according to the first embodiment, and the following description will focus on the differences from the computer 1 according to the first embodiment.

[0050] Fig. 11 is a diagram schematically illustrating the planar structure of a portion of the circuit layer 11 included in the computer 1 according to the present embodiment, which corresponds to the circuit diagram of Fig. 3, and Fig. 12 is a schematic cross-sectional view of the backplane 20 corresponding to the line CC shown in Fig. 11. As shown in Figs. 11 and 12, the circuit layer 11 according to the present embodiment differs from the circuit layer 11 according to the first embodiment in that the electrode of the storage capacitor 51 is composed of the pixel electrode PX and a conductive film 45 formed on the upper surface of the overcoat film 32.

[0051] 7 and 12 , the gate conductor film 41 and the source / drain conductor film 44 according to this embodiment do not have any portions that constitute the electrodes of the storage capacitor 51. On the other hand, in this embodiment, a conductive film 45 is formed on the upper surface of the overcoat film 32, and a second passivation film 33 is further formed on the upper surface of the conductive film 45. The pixel electrode PX is formed on the upper surface of the passivation film 33. The storage capacitor 51 according to this embodiment is configured with the conductive film 45 thus formed as the other electrode and the pixel electrode PX as one electrode. The passivation film 33 serves as a dielectric disposed between the electrodes of the storage capacitor 51. Similar to the common potential line CL described in the first embodiment, a predetermined common potential (e.g., ground potential) is supplied to the conductive film 45 from the host processor 3.

[0052] The conductive film 45 is configured to have a contact hole 45h at the same position as the contact hole 32h, the diameter of which is larger than that of the contact hole 32h in the overcoat film 32. Furthermore, the passivation film 33 is configured to have a contact hole 33h at the same position as the contact hole 31h in the passivation film 31, the contact hole 33h having approximately the same diameter as the contact hole 31h. The pixel electrode PX according to the present embodiment is connected to the source / drain conductor film 44 that constitutes the other controlled electrode of the pixel transistor 50 via the contact holes 31h and 46h.

[0053] The computer 1 according to this embodiment is similar to the first embodiment in that the plurality of sensor electrodes X1, Y1 used for detecting the position of the pen P by the electromagnetic induction (EMR) method are provided within the backplane 20 of the reflective display 2, and therefore, like the first embodiment, it is possible to realize a low-profile reflective display 2 that is compatible with pen input by the electromagnetic induction (EMR) method.

[0054] Next, a computer 1 according to a fourth embodiment of the present invention will be described. The computer 1 according to this embodiment differs from the computer 1 according to the third embodiment in that the connection between each gate line GL and the host processor 3 is realized via gate wiring GW extending within the display area A1. In other respects, the computer 1 according to this embodiment is similar to the computer 1 according to the third embodiment, and the following description will focus on the differences from the computer 1 according to the third embodiment.

[0055] Fig. 13 is a diagram showing the positional relationship of various wirings included in the reflective display 2 according to this embodiment. Fig. 14 is a diagram showing a schematic planar structure of a portion of the circuit layer 11 included in the computer 1 according to this embodiment, which corresponds to the circuit diagram in Fig. 3, and Fig. 15 is a schematic cross-sectional view of the backplane 20 corresponding to the line DD shown in Fig. 14.

[0056] The circuit layer 11 according to the present embodiment is configured to have a gate wiring GW and a gate via conductor GV for each gate line GL. The gate via conductor GV is a via conductor provided to penetrate the gate insulating film 42, and serves to connect the corresponding gate wiring GW and gate line GL to each other. The gate wiring GW is a wiring that extends in the y direction from the position of the gate via conductor GV toward the terminal area TA side, and is connected to the host processor 3 at its end on the terminal area TA side via a wiring SL.

[0057] The computer 1 according to this embodiment is similar to the third embodiment in that the plurality of sensor electrodes X1, Y1 used for detecting the position of the pen P by the electromagnetic induction (EMR) method are provided within the backplane 20 of the reflective display 2, and therefore, like the third embodiment, it is possible to realize a low-profile reflective display 2 that is compatible with pen input by the electromagnetic induction (EMR) method.

[0058] Furthermore, according to the computer 1 of this embodiment, the wiring SL in the bezel area A2 in the lateral direction as viewed from the terminal area TA can be reduced, so that the bezel area A2 can be narrowed.

[0059] Next, a computer 1 according to a fifth embodiment of the present invention will be described. The computer 1 according to this embodiment differs from the computer 1 according to the first embodiment in the way in which the sensor electrodes X1 and Y1 are used to detect the position of the pen P. In other respects, the computer 1 according to this embodiment is similar to the computer 1 according to the first embodiment, and therefore the following description will focus on the differences from the computer 1 according to the first embodiment.

[0060] 16 is a diagram showing the positional relationship of various wirings included in the reflective display 2 according to this embodiment. However, in this figure, the gate lines GL, data lines DL, and common potential lines CL are omitted. As shown in this figure, the reflective display 2 according to this embodiment is configured with switch groups 62 to 64, each of which is composed of a plurality of switch elements.

[0061] The switch group 62 is a group of switches consisting of a plurality of switch elements that connect two adjacent sensor electrodes Y1 with one sensor electrode Y1 sandwiched between them. Each switch element is provided midway through the base electrode BE that is connected to one end of each sensor electrode Y1, and is configured as a single-pole, single-throw switch having one terminal connected to one of the corresponding two sensor electrodes Y1 and the other terminal connected to the other of the corresponding two sensor electrodes Y1.

[0062] The switch group 63 is a switch group consisting of a plurality of switch elements that mutually connect two adjacent sensor electrodes Y1 among the plurality of sensor electrodes Y1 that are not connected to the switch group 62. Each switch element is provided midway through the base electrode BE that is connected to the other end of each sensor electrode Y1, and is configured as a single-pole, single-throw switch having one terminal connected to one of the corresponding two sensor electrodes Y1 and the other terminal connected to the other of the corresponding two sensor electrodes Y1.

[0063] The switch group 64 is a group of switches consisting of a plurality of switch elements that interconnect two adjacent sensor electrodes X1. Each switch element is provided midway on the base electrode BE that is connected to the end of each sensor electrode X1 that is farther from the terminal area TA, and is configured as a single-pole, single-throw switch having one terminal connected to one of the corresponding two sensor electrodes X1 and the other terminal connected to the other of the corresponding two sensor electrodes X1.

[0064] 17(a) and 17(b) are diagrams illustrating the process performed by the sensor controller 4 according to this embodiment to detect the position of the pen P using the sensor electrodes X1 and Y1. When starting the position detection process, the sensor controller 4 according to this embodiment first turns on all of the switch elements constituting the switch groups 62 and 64, as shown in FIG. 17(a). Then, every other switch element constituting the switch group 64 is turned on, and the sensor electrodes Y1 at the farthest ends in the y direction are selected from the multiple sensor electrodes Y1, excluding one sensor electrode Y1 at each end in the y direction. By turning on every other switch element constituting the switch group 64, multiple loop coils are formed. The sensor controller 4 includes a differential amplifier 4a (shown in FIG. 5) for each loop coil thus formed, and both ends of the formed loop coil are connected to the two input terminals of the corresponding differential amplifier 4a.

[0065] Next, the sensor controller 4 supplies an AC current i to one end of one sensor electrode Y1 adjacent to one side of the selected sensor electrode Y1. Ａ and an AC current iＢ and supply AC current i Ａ , i Ｂ The specific content of is as explained in the first embodiment. This causes a change in the magnetic flux above the selected sensor electrode Y1. When the inductor of the pen P enters the changing magnetic flux (alternating magnetic field), electromagnetic induction occurs between the sensor electrode Y1 and the inductor, causing a change in current in the inductor. As a result, an alternating magnetic field is emitted from the pen P, and an electromotive force is generated in the sensor electrode X1 located nearby. The electromotive force thus generated generates a current in each loop coil, which is supplied to the sensor controller 4 via the differential amplifier 4a. The sensor controller 4 supplies an AC current i to the sensor electrode Y1 for a predetermined time. Ａ , i Ｂ The current supplied from the differential amplifier 4a immediately after the loop coil 4 is supplied is acquired as a reception signal Rx from the pen P corresponding to each loop coil.

[0066] 17(b), the sensor controller 4 switches on and off a plurality of switch elements constituting the switch group 64, and connects both ends of the newly formed loop coil to each of the two corresponding input terminals of the differential amplifier 4a. Then, by performing the same process as above, the reception signal Rx from the pen P corresponding to each loop coil is acquired.

[0067] The sensor controller 4 repeatedly executes the above process while shifting the selected sensor electrode Y1 one by one. When the selection of all sensor electrodes Y1 and the subsequent process are completed, the sensor controller 4 acquires the reception signals Rx of each loop coil for each sensor electrode Y1. The sensor controller 4 derives the distribution of the signal strengths of the acquired multiple reception signals Rx on the operation surface 1a, and derives the position of the pen P based on the distribution.

[0068] The computer 1 according to this embodiment is similar to the first embodiment in that the plurality of sensor electrodes X1, Y1 used for detecting the position of the pen P by the electromagnetic induction (EMR) method are provided within the backplane 20 of the reflective display 2, and therefore, like the first embodiment, it is possible to realize a low-profile reflective display 2 that is compatible with pen input by the electromagnetic induction (EMR) method.

[0069] Furthermore, according to the computer 1 of this embodiment, it is possible to simultaneously acquire reception signals Rx from pens P corresponding to multiple loop coils, making it possible to derive the position of the pen P with high frequency.

[0070] 18A and 18B are diagrams illustrating the processing performed by the sensor controller 4 according to the first modified example of the present embodiment. The sensor controller 4 according to this modified example applies an AC current i to one end of each of the two sensor electrodes Y1 adjacent to one side of the selected sensor electrode Y1. Ａ and apply an AC current i to one end of each of the two adjacent sensor electrodes Y1 on the other side. Ｂ This differs from the sensor controller 4 of the present embodiment in that it supplies the AC current i Ａ , i Ｂ The method of supplying the alternating magnetic field is the same as that described in the first embodiment. This makes it possible to increase the intensity of the alternating magnetic field generated above the sensor electrode Y1.

[0071] 19(a) and 19(b) are diagrams illustrating the processing performed by the sensor controller 4 according to a second modified example of the present embodiment. The sensor controller 4 according to this modified example differs from the sensor controller 4 according to the present embodiment in that it emits an alternating magnetic field from the sensor electrode X1 and receives the alternating magnetic field emitted by the pen P at the sensor electrode Y1.

[0072] Specifically, when starting the position detection process, the sensor controller 4 according to this embodiment first turns on all of the switch elements constituting the switch group 64, as shown in FIG. 19( a). Then, in each of the switch groups 62 and 64, every other switch element is turned on, and of the multiple sensor electrodes X1, excluding two sensor electrodes X1 at each end in the x direction, the sensor electrodes X1 at the farthest end in the x direction are selected. By turning on every other switch element in each of the switch groups 62 and 64, multiple loop coils are formed. The sensor controller 4 includes a differential amplifier 4 a shown in FIG. 5 for each of the loop coils thus formed, and both ends of the formed loop coil are connected to the two input terminals of the corresponding differential amplifier 4 a.

[0073] Next, the sensor controller 4 supplies an AC current i to one end of two sensor electrodes X1 adjacent to one side of the selected sensor electrode X1. Ａ and apply an AC current i to one end of each of the two adjacent sensor electrodes X1 on the other side. Ｂ are supplied to the sensor electrode Y1. This causes a change in the magnetic flux above the selected sensor electrode X1. When the inductor of the pen P enters the changing magnetic flux (alternating magnetic field), electromagnetic induction occurs between the sensor electrode X1 and the inductor, causing a change in current in the inductor. As a result, an alternating magnetic field is sent out from the pen P, and an electromotive force is generated in the sensor electrode Y1 located nearby. The electromotive force thus generated generates a current in each loop coil, which is supplied to the sensor controller 4 via the differential amplifier 4a. The sensor controller 4 supplies the alternating current i to the sensor electrode X1 for a predetermined time. Ａ , i Ｂ The current supplied from the differential amplifier 4a immediately after the loop coil 4 is supplied is acquired as a reception signal Rx from the pen P corresponding to each loop coil.

[0074] 19(b), the sensor controller 4 switches on and off the multiple switch elements that make up the switch groups 62 and 64, connecting both ends of the newly formed loop coils to the two corresponding input terminals of the differential amplifier 4a, respectively.Then, by performing the same processing as above, the received signal Rx from the pen P corresponding to each loop coil is acquired.

[0075] The sensor controller 4 repeatedly executes the above process while shifting the selected sensor electrode X1 one by one. When the selection of all sensor electrodes X1 and the subsequent process are completed, the sensor controller 4 acquires the reception signal Rx at each loop coil for each sensor electrode X1. The sensor controller 4 derives the distribution of the signal strength of the acquired multiple reception signals Rx on the operation surface 1a, and derives the position of the pen P based on the distribution. In this way, this modification also makes it possible to derive the position of the pen P, similarly to the sensor controller 4 of this embodiment. Note that the sensor controller 4 of this modification can be configured, similarly to the sensor controller 4 of this embodiment, by applying an AC current i to one end of each of the sensor electrodes Y1 adjacent to one side of the selected sensor electrode Y1. Ａ and an AC current i Ｂ Of course, it may be configured to supply

[0076] Although the preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and it goes without saying that the present invention can be embodied in various forms without departing from the spirit of the present invention.

[0077] For example, in the above-described embodiments, the sensor electrodes X1 and Y1 are arranged in the circuit layer 11, but by arranging the sensor electrodes X1 and Y1 in another layer, it is possible to achieve a low profile of the reflective display 2 that is compatible with electromagnetic induction (EMR) pen input, as in the above-described embodiments. Specific examples will be described below.

[0078] 20 and 21 are diagrams showing examples of the layer structure of the reflective display 2 when the sensor electrodes X1 and Y1 are arranged on a layer other than the circuit layer 11. FIG.

[0079] 20 is an example in which a sensor electrode X1 is provided in the common electrode layer 14. In this case, the sensor electrode X1 may be provided separately from the common potential line CL in the common electrode layer 14, or the common potential line CL may be used as the sensor electrode X1 in a time-division manner. Also, a sensor electrode Y1 may be provided in the common electrode layer 14 instead of the sensor electrode X1. In this case, too, the sensor electrode Y1 may be provided separately from the common potential line CL in the common electrode layer 14, or the common potential line CL may be used as the sensor electrode Y1 in a time-division manner.

[0080] 20 is an example in which a sensor electrode X1 is provided in the touch sensor 16. In this case, the sensor electrode X1 may be provided separately from the sensor electrode X2, or the sensor electrode X2 may be used as the sensor electrode X1 by time division. Alternatively, the sensor electrode Y1 may be provided in the touch sensor 16 instead of the sensor electrode X1. In this case, the sensor electrode Y1 may be provided separately from the sensor electrode Y2, or the sensor electrode Y2 may be used as the sensor electrode Y1 by time division.

[0081] In addition, in each of the above embodiments, one of the sensor electrodes X1, Y1 is used to transmit an alternating magnetic field and the other is used to receive the reception signal Rx, but it is also possible to use both of them to receive the reception signal Rx.

[0082] 22 is a diagram showing the layer structure of the reflective display 2 when both sensor electrodes X1, Y1 are used to receive the reception signal Rx. As shown in the figure, in this modification, a battery 70 is provided inside the pen P, and the pen P emits an alternating magnetic field from an inductor using power supplied from this battery 70. The sensor controller 4 forms loop coils using each of the sensor electrodes X1, Y1, and derives the position of the pen P by receiving the alternating magnetic field emitted by the pen P at each loop coil.

[0083] 1 Computer 1a Operation surface 2 Reflective display 3 Host processor 4 Sensor controller 4a Differential amplifier 10 Substrate 11 Circuit layer 12 Pixel electrode layer 13 Reflective display layer 14 Common electrode layer 15, 17 Adhesion layer 16 Touch sensor 18 Cover glass 20 Backplane 31, 33 Passivation film 31h, 32h, 33h, 45h, 46h Contact hole 32 Overcoat film 41 Gate conductor film 42 Gate insulating film 43 Semiconductor film 44 Source drain conductor film 45 Conductive film 50 Pixel transistor 51 Storage capacitor 60 to 64 Switch group 70 Battery A1 Display area A2 Bezel area BE Base electrode C Reflective element CL Common potential line DL Data line F Finger GL Gate line GV Gate via conductor GW Gate wiring P Pen PX Pixel electrode SL Wiring TA Terminal area X1, Y1 Electromagnetic induction sensor electrode X2, Y2 Electric field sensor electrode

Claims

1. A reflective display comprising: a cover layer including an operation surface on which a position indicator having an inductor is operated; a reflective display layer including a plurality of reflective elements each reflecting light incident from said cover layer at a set gradation; a backplane provided at a position farther than said reflective display layer as viewed from said operation surface; and a common electrode layer including a common electrode provided between said cover layer and said reflective display layer, wherein said backplane has, within a display area overlapping with said plurality of reflective elements in a planar view, a plurality of pixel electrodes arranged in a matrix along a first direction and a second direction intersecting with the first direction, a plurality of data lines each extending along said first direction, and a plurality of first electromagnetic induction sensor electrodes each extending along said first direction, wherein said plurality of first electromagnetic induction sensor electrodes are used to detect the position of said position indicator on said operation surface by generating an electromagnetic induction effect between said inductor and said pixel electrodes.

2. The reflective display of claim 1, wherein the backplane further has, within the display area, a plurality of gate lines each extending along the second direction, and a plurality of second electromagnetic induction sensor electrodes each extending along the second direction, the plurality of second electromagnetic induction sensor electrodes being used to detect the position of the position indicator within the operation surface by generating an electromagnetic induction effect between the inductor and the second electromagnetic induction sensor electrodes.

3. The reflective display of claim 1, wherein the common electrode layer further has a plurality of second electromagnetic induction sensor electrodes each extending along the second direction within the display area, and the plurality of second electromagnetic induction sensor electrodes are used to detect the position of the position indicator within the operation surface by generating an electromagnetic induction effect between the inductor and the second electromagnetic induction sensor electrodes.

4. The reflective display of claim 1, further comprising a touch sensor provided between the cover layer and the common electrode layer, the touch sensor having a plurality of second electromagnetic induction sensor electrodes each extending along the second direction within the display area.

5. A reflective display comprising: a cover layer including an operation surface on which a position indicator having an inductor is operated; a reflective display layer including a plurality of reflective elements each reflecting light incident from said cover layer at a set gradation; a backplane provided at a position farther from said reflective display layer as viewed from said operation surface; and a common electrode provided between said cover layer and said reflective display layer, wherein said backplane has, within a display area overlapping with said plurality of reflective elements in a planar view, a plurality of pixel electrodes arranged in a matrix form along a first direction and a second direction intersecting with the first direction, a plurality of gate lines each extending along said second direction, and a plurality of second electromagnetic induction sensor electrodes each extending along said second direction, wherein said plurality of second electromagnetic induction sensor electrodes are used to detect the position of said position indicator on said operation surface by generating an electromagnetic induction effect between said inductor and said pixel electrodes.

6. A reflective display comprising: a cover layer including an operation surface on which a position indicator having an inductor is operated; a reflective display layer including a plurality of reflective elements each reflecting light incident from the cover layer at a set gradation; a backplane provided at a position farther from the reflective display layer as viewed from the operation surface; and a common electrode provided between the cover layer and the reflective display layer, wherein the backplane has, within a display area overlapping with the plurality of reflective elements in a planar view, a plurality of pixel electrodes arranged in a matrix along a first direction and a second direction intersecting the first direction, and a plurality of linear conductors each extending along the first direction, wherein the plurality of linear conductors are used as either a plurality of data lines used for supplying data signals to the pixel electrodes by time division, or a plurality of first electromagnetic induction sensor electrodes used for detecting the position of the position indicator on the operation surface by generating an electromagnetic induction effect between the inductor.

7. A reflective display as described in claim 2, wherein the backplane further has a plurality of pixel transistors within the display area, the pixel transistors corresponding to each of the plurality of pixel electrodes, a control electrode of each of the plurality of pixel transistors being connected to one of the plurality of gate lines, one controlled electrode of each of the plurality of pixel transistors being connected to one of the plurality of data lines, and the other controlled electrode of each of the plurality of pixel transistors being connected to the corresponding pixel electrode.

8. The reflective display according to claim 7, wherein the backplane further comprises a plurality of storage capacitors provided in the display area corresponding to each of the plurality of pixel electrodes, and one electrode of each of the plurality of storage capacitors is connected to the corresponding pixel electrode.

9. The reflective display of claim 8, wherein the plurality of first electromagnetic induction sensor electrodes extend between the data lines and the storage capacitors adjacent in the second direction.

10. The reflective display according to claim 9, wherein the number of the first electromagnetic induction sensor electrodes is smaller than the number of the data lines.

11. The reflective display of claim 8, wherein the backplane further comprises an insulating film covering the plurality of data lines, and a plurality of conductive films provided between each of the plurality of pixel electrodes and the insulating film, and the other electrode of each of the storage capacitors is formed by a corresponding one of the conductive films.

12. A reflective display as claimed in claim 2 or 5, wherein the plurality of second electromagnetic induction sensor electrodes are connected to each other by base electrodes provided at the ends.

13. The reflective display according to claim 12, wherein the base electrode is disposed in an area outside the display area in a plan view.

14. A reflective display as described in claim 2 or 5, wherein each of the multiple second electromagnetic induction sensor electrodes generates an electromagnetic induction effect between itself and the inductor by causing a change in magnetic flux when an alternating current supplied from a sensor controller flows through it.

15. A reflective display as described in claim 1, wherein each of the plurality of first electromagnetic induction sensor electrodes generates an electromagnetic induction effect between the inductor and the electromotive force corresponding to a change in magnetic flux caused by a change in current flowing through the inductor.

16. A reflective display as described in claim 2, wherein each of the plurality of first electromagnetic induction sensor electrodes generates an electromagnetic induction effect between itself and the inductor by causing a change in magnetic flux when an alternating current supplied from a sensor controller flows through it.

17. A reflective display as described in claim 16, wherein each of the plurality of second electromagnetic induction sensor electrodes generates an electromagnetic induction effect between the inductor and the electromotive force generated in response to a change in magnetic flux caused by a change in current flowing through the inductor.

18. The reflective display according to claim 2 or 5, wherein each of the plurality of gate lines is connected to a routing wiring at either one end or the other end, alternately when viewed in the first direction.

19. The reflective display of claim 2 or 5, wherein each of the plurality of gate lines is connected to a routing line within the display area.