JP2008058554A - Display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display panel with additional functions other than image display functions. <P>SOLUTION: The display panel 17, mounted with peripheral drive circuits, such as scanning line driving circuits 13 and 14, a data line drive circuit 15, and a precharge circuit 16 together with a pixel array part 12, has pattern wirings 20A spirally formed by two or more turns at its outer peripheral part (peripheral edge part), and the pattern wirings 20A are used as a coil. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a display device, and more particularly to a panel type (planar type) display device in which pixels including electro-optic elements are arranged in a matrix (matrix shape).

  In recent years, in the field of display devices, panel type display devices such as liquid crystal display (LCD), EL (electro luminescence) display, plasma display panel (PDP), etc. are thin, light, Due to its high-definition features, it is becoming the mainstream in place of conventional CRT (Cathode Ray Tube) display devices.

  This panel type display device basically includes a display panel in which pixels including electro-optic elements are arranged in a matrix (matrix shape) on an insulating substrate, and a peripheral driving circuit. Yes. A wiring layer called a so-called guard ring layer is pattern-wired on the outer periphery of the display panel for the purpose of inspecting the display panel. (For example, refer to Patent Document 1).

JP-A-10-268784

  However, considering that the guard ring layer is formed for the purpose of inspecting the display panel, the display panel has only an image display function. On the other hand, panel-type display devices are widely used as display units of portable devices such as mobile phones. When considering applications to various electronic devices such as portable devices, additional functions other than the image display function are required for the display panel.

  Accordingly, an object of the present invention is to provide a display device in which an additional function other than the image display function is provided on the display panel.

  A display device according to the present invention includes a display panel in which pixels including an electro-optical element are arranged, and wiring formed on the outer peripheral portion of the display panel with two or more turns.

  In the display device having the above structure, the wiring has a function as a coil when the wiring is formed on the outer peripheral portion of the display panel with two or more turns. Possible applications of the coil include, for example, a secondary coil of a power supply circuit that generates a power supply voltage used in the display panel, and a coil for communication between the display panel and the outside.

  According to the present invention, since the wiring can be used as a coil by forming the wiring in the outer peripheral portion of the display panel with two or more turns, the display panel can have additional functions other than the image display function. Can be given.

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

[First Embodiment]
FIG. 1 is a system configuration diagram showing an outline of the configuration of a display device according to the first embodiment of the present invention. As shown in FIG. 1, the display device according to the present embodiment includes a pixel array unit 12 in which pixels 11 including electro-optical elements are two-dimensionally arranged in a matrix (matrix shape), and the periphery of the pixel array unit 12. The driving circuit includes scanning line driving circuits 13 and 14, a data line driving circuit 15, and a precharge circuit 16, and these peripheral driving circuits are mounted on the same insulating substrate as the pixel array unit 12 to form a display panel 17. It is said.

  In the pixel array unit 12, scanning lines 18-1 to 18-m are wired for each pixel row with respect to a pixel array of m rows and n columns, and data lines (signal lines) 19-1 to 19- n is wired. The scanning line drive circuits 13 and 14 are connected to both ends of the scanning lines 18-1 to 18-m, and scan lines 18-1 to 18-m for selectively scanning each pixel 11 of the pixel array unit 12 in units of rows. Drive.

  The data line driving circuit 15 drives the data lines 19-1 to 19-n in order to write a video signal to each pixel 11 in the row selectively scanned by the scanning line driving circuits 13 and 14. The precharge circuit 16 applies a precharge signal of a predetermined level to each pixel 11 in the same selected row before the video line is written by the data line drive circuit 15 to each pixel 11 in the selected row by the scanning line drive circuits 13 and 14. Data lines 19-1 to 19-n are driven.

  As described above, in the display panel 17 in which peripheral drive circuits such as the scanning line drive circuits 13 and 14, the data line drive circuit 15, and the precharge circuit 16 are mounted together with the pixel array unit 12, The pattern wiring 20A is spirally formed of a metal material such as aluminum (Al) or molybdenum (Mo) with two or more turns. FIG. 1 shows a pattern wiring 20 in the case of two-turn winding for the sake of simplification of the drawing.

  FIG. 2 shows a cross section taken along the line AA ′ of FIG. As shown in FIG. 2, the pattern wiring 20A is spirally formed in the same wiring layer. Then, both ends of the pattern wiring 20A are connected to two terminals (pads) 21A and 21B located at both ends of the terminal group (pad group), respectively, as shown in FIG.

  As is apparent from FIG. 1, there are various types of terminals between the other terminals 22 and the peripheral drive circuits such as the scanning line drive circuits 13, 14, the data line drive circuit 15, and the precharge circuit 16. A wiring group 23 composed of wirings is formed. Since these wiring groups 23 are also formed in the same wiring layer as the pattern wiring 20 </ b> A, the pattern wiring 20 </ b> A intersects the wiring group 23 in the vicinity of the terminal group 22.

  Therefore, in the pattern wiring 20A, the pattern wiring 20A ′ in the vicinity of the terminal group 22 is formed in a wiring layer different from the wiring part of the main part of the pattern wiring 20A. Then, by electrically connecting both ends of the pattern wiring 20A ′ and both ends of the main wiring portion of the pattern wiring 20A via the contact portions 24A and 24B, the wiring shape in a plan view of the pattern wiring 20A becomes spiral. .

  Thus, the pattern wiring 20A according to the first embodiment can be used as a coil because it is formed in a spiral shape with two or more turns. Specific usage as a coil will be described later. Further, the pattern wiring 20A can be used as a coil, and at the same time, since the pattern wiring 20A is formed on the peripheral edge of the display panel 17, it can also be used as an inspection wiring for the display panel 17.

  Specifically, the display panel 17 is inspected for defects such as cracks and chips in the display panel 17 in the manufacturing stage. If the display panel 17 has a defect such as a crack or chip, the pattern wiring 20 </ b> A formed on the peripheral edge of the display panel 17 is disconnected due to the crack or chip of the display panel 17. Therefore, the presence or absence of defects such as cracks or chips in the display panel 17 can be inspected by measuring the resistance value between the terminals 21A and 21B in the inspection process at the manufacturing stage. As a result, the quality of the display panel 17 can be determined.

[Second Embodiment]
FIG. 3 is a system configuration diagram showing an outline of the configuration of the display device according to the second embodiment of the present invention. In FIG. 3, the same parts as those in FIG.

  The display device according to the present embodiment is the same as the first embodiment in that the pattern wiring 20B is formed in a spiral shape with the number of turns of two or more turns on the outer peripheral portion (peripheral portion) of the display panel 17. In the first embodiment, the pattern wiring 20A is formed in the same wiring layer, but in the present embodiment, the pattern wiring 20B is formed in a different wiring layer.

  In FIG. 3, for simplification of the drawing, the pattern wiring 20 </ b> B in the case of two-turn winding is illustrated. In order to facilitate understanding, the pattern wiring 20B-1 formed in the first wiring layer is illustrated by a one-dot chain line, and the pattern wiring 20B-2 formed in the second wiring layer is illustrated by a two-dot chain line. This is shown in the figure.

  In the first wiring layer, terminals (pads) 21A and 21B and other terminal groups 22 are formed together with the pattern wiring 20B-1, and one end of the pattern wiring 20B-1 and the terminal 21A are electrically connected in the wiring layer. Connected to. The other end of the pattern wiring 20B-1 is electrically connected to one end of the pattern wiring 20B-2 formed in another wiring layer via the contact portion 25A.

  Since the pattern wiring 20B-2 is formed in a wiring layer different from the wiring layer in which the terminals 21A and 21B and other terminal groups 22 are formed, the pattern wiring 20B-2 crosses the wiring connected to each terminal of these terminal groups. Will be formed. The other end of the pattern wiring 20B-2 is electrically connected to the terminal 24B via the contact portion 25B and the first layer wiring.

  FIG. 4 shows a cross section taken along the line BB ′ of FIG. Here, the case where the number of turns of the pattern wiring 20B is two turns is shown, but in each of the first and second wiring layers, the pattern wirings 20B-1 and 20B-2 are spirally wound in multiple turns. Can be formed. At this time, when adopting a configuration in which the terminals 21A and 21B and other terminal groups 22 are formed in the same wiring layer as the pattern wiring 20B-1, the pattern wiring 20B-1 and the terminal group are used as described in the first embodiment. It is necessary to provide a contact portion for avoiding the intersection with the wiring connected to each terminal.

  However, when adopting a configuration in which the terminals 21A, 21B and the other terminal groups 22 are formed in a wiring layer different from the pattern wiring 20B-1, the intersection of the pattern wiring 20B-1 and the wiring connected to each terminal of the terminal group. It is not necessary to provide a contact portion for avoiding the above, and each of the pattern wirings 20B-1 and 20B-2 can be freely formed into a spiral shape by winding many times without considering the avoidance of intersection with other wirings. it can.

  In this way, the pattern wiring 20B-1 and the pattern wiring 20B-2 are formed in different wiring layers, and each of the pattern wirings 20B-1 and 20B-2 is spirally formed in a number of turns to thereby form the display panel 17. The pattern wiring 20B is spirally wound with a larger number of turns than in the first embodiment in which the pattern wiring 20B-1 and the pattern wiring 20B-2 are formed in the same wiring layer in the space of the limited frame (periphery). Can be formed.

  Similarly to the pattern wiring 20A according to the first embodiment, the pattern wiring 20B according to the second embodiment can be used as a coil because it is formed in a spiral shape with two or more turns. Since the pattern wiring 20 </ b> B is formed on the peripheral edge of the display panel 17, it can also be used as the inspection wiring for the display panel 17.

  As described above, in the display panel 17 in which peripheral drive circuits such as the scanning line drive circuits 13 and 14, the data line drive circuit 15, and the precharge circuit 16 are mounted together with the pixel array unit 12, the outer peripheral portion (peripheral portion). In addition, since the pattern wirings 20A and 20B can be used as a coil by forming the pattern wirings 20A and 20B in a spiral shape with two or more turns, the display panel 17 has an additional function other than the image display function. Can have a function.

[Application example of pattern wiring]
Next, specific usage examples of the pattern wiring 20 (20A, 20B) according to the first and second embodiments will be described.

When the pattern wiring 20 (20A, 20B) is used as a coil, the coil inductance L can be increased by increasing the number N of turns of the pattern wiring 20 or increasing the cross-sectional area S of the wiring. The relationship of the following equation is established between the inductance L and the number of turns N and the cross-sectional area S.
L∝N ² × S
The cross-sectional area S of the wiring is determined with respect to the outer size of the display panel 17, but the number N of turns of the pattern wiring 20 can be increased to some extent as described in the above embodiments.

(Usage example 1)
FIG. 5 is a circuit diagram showing a usage example 1 of the pattern wiring 20. In this usage example 1, the pattern wiring 20 is used as a secondary coil of a transformer circuit in a power supply circuit.

  As shown in FIG. 5, the power supply circuit 30 includes a transformer circuit 31, a rectifier circuit 32, and a secondary battery (charging capacity) 33. In the power supply circuit 30 according to this example, a half-wave rectifier circuit including one diode is used as the rectifier circuit 32.

  The transformer circuit 31 includes a primary coil 311 to which an AC voltage is applied, and a secondary coil 312 that induces an AC voltage by electromagnetic induction between the primary coil 311, and pattern wiring is used as the secondary coil 312. 20 is used. That is, the secondary coil 312 made of the pattern wiring 20 is provided in the display panel 17, whereas the primary coil 311 is provided outside the display panel 17.

  In the power supply circuit 30 configured as described above, the transformer circuit 31 operates to cause a predetermined potential difference between the nodes A and B. Accordingly, the secondary battery 33 is charged, and the potential difference between the nodes A and B is changed to the power source. The voltage is supplied from the terminals 34 and 35 to the drive target circuit 40. Here, the voltage value of the power supply voltage is determined by the turn ratio between the primary coil 311 and the secondary coil 312 of the transformer circuit 31. When the transformer circuit 31 is not working, the charging voltage of the secondary battery 33 is supplied from the terminals 34 and 35 to the drive target circuit 40 as a power supply voltage.

  The drive target circuit 40 of the power supply circuit 30 is a peripheral drive circuit mounted on the display panel 17 together with the pixel array unit 12, for example, a shift register constituting the scanning line drive circuits 13 and 14, or illustrated in FIGS. Is omitted, but the level shifter (shifting the level of a signal input from the outside of the display panel 17 to a predetermined level and giving it to the scanning line driving circuits 13, 14, the data line driving circuit 15, the precharge circuit 16, etc. Level conversion circuit).

  However, the drive target circuit 40 of the power supply circuit 30 is not limited to the drive circuit around the pixel array unit 12 mounted on the display panel 17, that is, the circuit inside the display panel 17. For example, for example, a driving circuit (an IC driving outside the panel) or the like that is provided outside the display panel 17 and generates a video signal or a synchronization signal to be input to the display panel 17 and performs display driving is used as a power source. It is also possible to use the circuit to be driven 40 of the circuit 30.

  In the above application example, the power supply circuit 30 is exemplified by a circuit configuration in which the rectifier circuit 32 is a half-wave rectifier circuit. However, as shown in FIG. 6, the rectifier circuit 32 'is a full-wave rectifier circuit. The power supply circuit 30 ′ having the circuit configuration as described above may be used, and according to the power supply circuit 30 ′, the efficiency of the rectifier circuit 32 ′ can be improved.

  Further, in the above usage example, the configuration in which the rectifier circuit 32 and the secondary battery 33 of the power supply circuit 30 are built in the display panel 17 is taken as an example. However, as shown in FIG. It can also be provided as an external circuit of the display panel 17.

  The primary coil 311 of the transformer circuit 31 is the same as in the above example of use, but is patterned on an external substrate 41 different from the display panel 17. By providing the external substrate 41 so as to overlap the display panel 17, an alternating voltage is induced at both ends of the secondary coil 312 by electromagnetic induction between the primary coil 311 and the secondary coil 312. It will be.

  By the way, in the power supply circuits 30 and 30 ′, the secondary battery 33 is indispensable. However, when the secondary battery 33 is built in the display panel 17, the capacity of the secondary battery 33 is set to the display panel. 17 can be formed. Here, as the display panel 17, for example, an organic EL panel using a low-temperature polysilicon TFT (Thin Film Transistor) will be described as an example.

  As shown in FIG. 8, the organic EL panel 50 includes a molybdenum (Mo) layer 51, an insulating film 52, a polysilicon (PS) layer 53, an insulating film 54, an aluminum (Al) layer 55, an insulating film 56, and an organic EL element. A transparent conductive film 57 forming the anode electrode, an organic layer 58, and a metal layer 59 serving as a cathode electrode of the organic EL element are sequentially laminated. The organic layer 58 has a structure in which a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer are sequentially deposited.

  In the organic EL panel 50 having such a layer structure, first, an example in which the aluminum layer 55 is used as a basic layer for capacitance formation is shown in FIG. As shown in FIG. 9, the molybdenum layer 51 and the metal layer 59 in a floating state are electrically connected to the aluminum layer 55 via the contact portions 61 and 62. Further, the floating polysilicon layer 53 and the transparent conductive film 57 are connected to a fixed potential, for example, a ground potential.

  As a result, a capacitor C11 is formed between the molybdenum layer 51 and the polysilicon layer 53, a capacitor C12 is formed between the polysilicon layer 53 and the aluminum layer 55, and between the aluminum layer 55 and the transparent conductive film 57. The capacitor C13 is formed, the capacitor C14 is formed between the transparent conductive film 57 and the metal layer 59, and the capacitors C11 to C14 are electrically connected in parallel. As a result, the combined capacity of these capacities C11 to C14 can be used as the capacity constituting the secondary battery 33.

  Next, FIG. 10 shows an example in which the molybdenum layer 51 is used as a basic layer for capacitance formation. As shown in FIG. 10, the aluminum layer 55 and the metal layer 59 in a floating state are electrically connected to the molybdenum layer 51 via the contact portions 63 and 64. Further, the polysilicon layer 53 and the transparent conductive film 57 in a floating state are connected to a fixed potential, for example, a ground potential.

  As a result, a capacitor C21 is formed between the molybdenum layer 51 and the polysilicon layer 53, a capacitor C22 is formed between the polysilicon layer 53 and the aluminum layer 55, and the space between the aluminum layer 55 and the transparent conductive film 57. The capacitor C23 is formed, the capacitor C24 is formed between the transparent conductive film 57 and the metal layer 59, and the capacitors C21 to C24 are electrically connected in parallel. As a result, the combined capacity of these capacities C21 to C24 can be used as the capacity constituting the secondary battery 33.

  Here, when the pattern wiring 20 is used as the secondary coil 312 of the transformer circuit 31 in the power supply circuits 30 and 30 ′, the capacitance formed in the display panel 17 (in this example, the organic EL panel 50) Although the case where it used as a capacity | capacitance which comprises the secondary battery 33 of the power supply circuits 30 and 30 'was mentioned as an example, it is not restricted to this usage example.

  For example, when the series resonant circuit (A) or the parallel resonant circuit (B) is configured on the display panel 17 using the pattern wiring 20 as the coil L as shown in FIG. 9 and the capacitance formed in the panel as shown in FIG. 10 can be used as the capacitance C of the series resonance circuit (A) or the capacitance C of the parallel resonance circuit (B).

(Usage example 2)
Next, as a usage example 2 of the pattern wiring 20, a case where the pattern wiring 20 is used as a communication coil, for example, an antenna coil will be described as an example.

  A panel type display device such as a liquid crystal display device or an organic EL display device has advantages such as a thin shape, a light weight, and a high definition, and is therefore mounted as a display unit in a mobile device such as a mobile phone. As a matter of course, a portable device such as a cellular phone has a built-in antenna in order to communicate with the outside.

  Therefore, when a panel type display device such as a liquid crystal display device or an organic EL display device is mounted as a display unit in a portable device, the pattern wiring 20 formed in a spiral shape on the outer peripheral portion (peripheral portion) of the display panel 17 is provided as an antenna. Use as a coil. As a result, it is not necessary to provide an antenna on the main body side of a portable device such as a cellular phone, so that the added value of the display panel 17 can be increased.

  In particular, a mobile phone called a so-called Osaifu-Keitai (registered trademark of NTT DoCoMo) that has a simple and convenient prepaid electronic money function that can be paid simply by bringing it close to a dedicated device, that is, communications other than calls and e-mails. In the cellular phone having a function, the pattern wiring 20 formed in a spiral shape on the outer peripheral portion of the display panel 17 can also be used as the communication coil.

  As mentioned above, although the usage example in the case of using the pattern wiring 20 formed in the spiral shape in the outer peripheral part of the display panel 17 as a coil was demonstrated as usage examples 1 and 2, these usage examples are only examples and are limited to these. It is not a thing.

It is a system configuration figure showing the outline of the composition of the display concerning a 1st embodiment of the present invention. It is AA 'arrow sectional drawing of FIG. It is a system block diagram which shows the outline of a structure of the display apparatus which concerns on 2nd Embodiment of this invention. FIG. 4 is a cross-sectional view taken along the line BB ′ in FIG. 3. It is a circuit diagram which shows the usage example 1 of pattern wiring. It is a circuit diagram which shows the circuit example in case a rectifier circuit consists of a full wave rectifier circuit. It is a circuit diagram which shows the modification of the usage example 1 of pattern wiring. It is sectional drawing which shows an example of the layer structure of an organic electroluminescent panel. It is sectional drawing which shows the example in the case of making an aluminum (Al) layer into a basic layer of capacity | capacitance formation in an organic electroluminescent panel. It is sectional drawing which shows the example in the case of making a molybdenum (Mo) layer into a basic layer of capacity | capacitance formation in an organic electroluminescent panel. It is a circuit diagram which shows the other usage example of a coil, (A) has shown the series resonance circuit, (B) has shown the parallel resonance circuit, respectively.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... Pixel, 12 ... Pixel array part, 13, 14 ... Scan line drive circuit, 15 ... Data line drive circuit, 16 ... Precharge circuit, 17 ... Display panel, 18-1 to 18-m ... Scan line, 19- 1 to 19-n... Data line (signal line) 20, 20A, 20B... Pattern wiring, 30, 30 '... power supply circuit, 31 ... transformer circuit, 32, 32' ... rectifier circuit, 33 ... secondary battery (charging) Capacity), 40 ... driven circuit, 311 ... primary coil, 312 ... secondary coil

Claims (7)

A display panel in which pixels including electro-optic elements are arranged;
A display device comprising: an outer peripheral portion of the display panel; and a wiring formed with two or more turns. The display device according to claim 1, wherein the wiring is used as a coil. The display device according to claim 2, wherein the coil is a secondary coil of a transformer circuit in a power supply circuit that generates a power supply voltage used in the display panel. The display device according to claim 2, wherein the coil is a coil for communication between the display panel and the outside. The display device according to claim 1, wherein the wiring is also used as a wiring for inspection of the display panel. The display device according to claim 1, wherein the wiring is formed in the same wiring layer of the display panel. The display device according to claim 1, wherein the wiring is formed in a different wiring layer of the display panel via a contact portion that electrically connects the different wiring layers.

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