Light-emitting module

Abstract

To provide a light emitting module capable of easily increasing light emission intensity.SOLUTION: A light emitting module (1) includes a light emitting unit having an organic EL light emitting unit (21), an antenna coil (11) that wirelessly receives power from the outside, an integrated circuit (14) that is connected to the antenna coil (11) and operates with the power received by the antenna coil (11), a rectifier circuit (13) that rectifies the power received by the antenna coil (11) and outputs the rectified power to the light emitting unit, and resistance elements (R1, R2) that are positioned in series with the integrated circuit (14) and in parallel with the antenna coil (11).SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a light emitting module. [Background technology]

[0002] Conventionally, there are technologies such as IC cards and tags that receive power wirelessly and transmit and receive information using near-field communication (NFC), etc. There is also a technology that uses electromagnetic induction in a coil to make light-emitting elements such as organic light-emitting diodes (OLEDs) emit light using power received wirelessly (Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-106136 Summary of the Invention [Problem to be solved by the invention]

[0004] However, due to the large capacity of OLEDs, it is difficult to obtain sufficient luminous intensity using conventional wireless power supply.

[0005] An object of the present invention is to provide a light-emitting module that can easily increase the light-emitting intensity. [Means for solving the problem]

[0006] In order to achieve the above object, the present invention provides a light-emitting section having an organic EL element; a wireless power receiving unit that receives power wirelessly from an external device; an integrated circuit connected to the wireless power receiving unit and operating on power received by the wireless power receiving unit; a rectifier circuit that rectifies the power received by the wireless power receiving unit and outputs the rectified power to the light emitting unit; an impedance element located in series with the integrated circuit and in parallel with the wireless power receiving unit; The light emitting module includes: [Effects of the Invention]

[0007] According to the present invention, there is an effect that the light emission intensity of the light emitting module can be easily increased. [Brief explanation of the drawings]

[0008] [Figure 1] 1A and 1B are diagrams illustrating the configuration of a light-emitting module according to an embodiment of the present invention. [Figure 2] 10 is a modified example of the circuit diagram of the light emitting module. [Figure 3] 10 is a graph showing the results of measuring the luminance value relative to the capacitance of a capacitor and the resistance value of a resistor element. [Figure 4] 10A and 10B are diagrams illustrating modified examples of the positional relationship of each component in the light-emitting module. [Figure 5] 10A and 10B are diagrams illustrating modified examples of the positional relationship of each component in the light-emitting module. [Figure 6] 10A and 10B are diagrams illustrating modified examples of the positional relationship of each component in the light-emitting module. [Figure 7] 10A and 10B are diagrams illustrating a modified example of the connection between the circuit board and the light emitting board. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a diagram illustrating the configuration of a light-emitting module 1 according to this embodiment. FIG. 1(a) is a plan view of the light-emitting module 1 as seen from above. Here, the circuit and each component are described as being all visible, but in reality they may be covered by a cover or the like and be invisible. FIG. 1(b) is a circuit diagram of the light-emitting module 1. FIG. 1(c) is a cross-sectional view taken along the cross-sectional line AA in FIG. 1(a). Note that the aspect ratio in this cross-sectional view does not necessarily reflect the actual ratio, and is for illustrative purposes only.

[0010] The light-emitting module 1 includes a circuit board 10 and a light-emitting board 20. The light-emitting board 20 has an organic EL (Electro-Luminescence) light-emitting unit 21 (organic EL element) and a capacitor 22 (first capacitive element). The organic EL light-emitting unit 21 is, although not limited to, a panel-shaped unit, and forms an organic EL panel together with the base material of the light-emitting board 20. The organic EL light-emitting unit 21 can be lit by power supplied from the circuit board 10. The organic EL light-emitting units 21 may be driven collectively by a single electrode, or may be arranged in a matrix and each of the organic EL light-emitting units 21 may be driven by a separate electrode.

[0011] The organic EL light-emitting unit 21 has, for example, a pair of electrodes on the base material of the light-emitting substrate 20 and a thin-film organic light-emitting layer laminated between these electrodes. At least the upper surface of the electrodes is optically transparent, preferably transparent. Such a transparent electrode is, for example, an ITO (indium-tin oxide) electrode, but is not limited thereto. The organic EL light-emitting unit 21 (or the entire light-emitting substrate 20) may be sealed with a recessed sealing glass cap, an inorganic insulating film such as silicon oxide or silicon nitride formed on the organic EL light-emitting unit 21, or an aluminum foil or barrier film adhered via an epoxy resin or acrylic resin. In addition to the organic EL light-emitting unit 21, the light-emitting unit of this embodiment may also include a sealing layer made of these sealing members or an adhesive layer for adhering the sealing member.

[0012] The base material of the light-emitting substrate 20 is, for example, glass, metal, or resin. When light from the organic EL light-emitting unit 21 is emitted from the base side (rear side), the base material is optically transparent. Resin substrates and resin films are preferred as optically transparent base materials in terms of flexibility in thickness, weight, and shape. Transparent resin films are particularly preferred in terms of productivity, light weight, and flexibility. Examples of flexible resins include polyester-based resins such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and modified polyester; polyolefin resins such as polyethylene (PE) resin, polypropylene (PP) resin, polystyrene resin, and cyclic olefin-based resin; vinyl-based resins such as polyvinyl chloride and polyvinylidene chloride; polyether ether ketone (PEEK) resin; polysulfone (PSF) resin; polyethersulfone (ES) resin; polycarbonate (PC) resin; polyamide resin; polyimide resin; acrylic resin; triacetyl cellulose (TC) resin; and combinations thereof. The flexible resin may be an unstretched film or a stretched film.

[0013] The transparency of a resin may be determined, for example, by the total light transmittance obtained by a measurement method conforming to JIS K 7361-1:1997 (Test method for total light transmittance of plastic transparent materials). Here, the total light transmittance is preferably 50% or more, and more preferably 80% or more.

[0014] The light emitting substrate 20 may also have a gas barrier layer. The gas barrier layer has a water vapor permeability (at 25±0.5°C and a relative humidity of 90±2% RH) of 0.01 g / (m), as measured by a method conforming to JIS K 7129-1992, for example. 2 The gas barrier film may be a film (gas barrier film) having an oxygen permeability of 1.0×10 or less as measured by a method in accordance with JIS K 7126-1987. 3 ml / (m 2 ·24h·atm) or less, and the water vapor permeability is 1.0×10 -5 g / (m 224h) or less. Alternatively, the base material of the light emitting substrate 20 itself may have the properties of the gas barrier layer (gas barrier properties). There are no particular limitations on the material as long as it has the above properties.

[0015] When a voltage is applied between the pair of electrodes, the excited electrons and holes in the thin-film organic light-emitting layer recombine and release energy, causing the organic EL light-emitting section 21 to emit light.

[0016] The capacitor 22 is located between the rectifier circuit 13 and the organic EL light-emitting unit 21 on the circuit board 10, in parallel with the organic EL light-emitting unit 21. This capacitor 22 reduces the impedance between the input and output of the rectifier circuit 13. The capacitor 22 may be a chip capacitor, particularly a multilayer ceramic chip capacitor. Alternatively, as long as the required capacitance can be obtained, the capacitor 22 may be formed of a pair of electrode films located on both sides of the insulating base of the light-emitting substrate 20 (or the insulating base 10a as in the modified example described below).

[0017] The circuit board 10 has a circuit pattern made of a conductive material attached to or inside an insulating substrate (insulating base 10a). The circuit board 10 is preferably flexible. For example, the circuit board 10 may be a flexible printed circuit (FPC) made of a thin, soft insulating base 10a such as polyimide, PET, or paper, on which a conductive pattern made of copper foil, aluminum foil, or the like is formed. This allows the wiring 31 and 32 on the circuit board 10 to be flexible wiring. Alternatively, a TCP substrate (Tape-Carrier Package) or the like may be used as the flexible circuit board 10 (insulating base 10a). Alternatively, when the circuit board 10 is a rigid substrate, the insulating base may be made of, for example, glass epoxy or glass composite. Furthermore, silver paste or the like may be used for the conductive pattern. The circuit board 10 has and supports an antenna coil 11, a capacitive element 12 (second capacitive element), a rectifier circuit 13, an integrated circuit (IC) 14, resistive elements R1 and R2, and the like.

[0018] The antenna coil 11 is an induction coil having a ring-shaped portion. The ring-shaped portion may be a conductor pattern of a metal member formed on the insulating base 10a. The antenna coil 11 acquires an electric signal corresponding to an external electromagnetic field fluctuation through electromagnetic induction. Furthermore, constant external electromagnetic field (magnetic flux) fluctuations are continuously input to the antenna coil 11, thereby wirelessly supplying (receiving) power to the circuit board 10. That is, the antenna coil 11 functions as a wireless power receiving unit. The light-emitting module 1 can operate without its own battery while receiving external power. Furthermore, signals can be superimposed by appropriately modulating the electromagnetic field fluctuations. The modulation method is not particularly limited, but may be one that is resistant to current and voltage fluctuations, such as PSK (Phase-Shift Keying) modulation. The antenna coil 11 may be wound around the periphery of the circuit board 10 multiple times. Furthermore, a magnetic sheet may be superimposed on the antenna coil 11. This reduces loss associated with energy transfer between the antenna coil 11 and the surrounding conductive members. The magnetic sheet preferably has a relative magnetic permeability of 100 or more.

[0019] Note that wireless power supply does not have to use electromagnetic induction. For example, power supply may be via magnetic resonance, radio wave reception, or electric field coupling. In magnetic resonance, power is supplied by resonating a resonator, which is a combination of a coil and a capacitor, between communication-connected devices. In electric field coupling, power is supplied by utilizing the electric field between electrodes on the transmitting and receiving sides.

[0020] Both ends of the antenna coil 11 are connected to both electrodes of the capacitive element 12 and a pair of input terminals of the rectifier circuit 13. The capacitive element 12 is located in parallel with the antenna coil 11. The inductance of the antenna coil 11 is determined appropriately depending on the number of turns, etc. For example, the inductance may be 0.5 μH to 4.0 μH. The impedance at the receiving frequency is determined by the inductance and capacitance of the antenna coil 11. The receiving frequency is a frequency related to the RFID (Radio Frequency Identifier) ​​to be input, for example, 13.56 MHz. 13.56 MHz is a frequency related to the Near-Field Communication (NFC) standard. The impedance is set to a range that is not large relative to this receiving frequency. The capacitance of the capacitive element 12 may be on the order of several tens to several hundred pF. In addition, in order to suppress a decrease in the brightness of the organic EL light-emitting unit 21, the series resistance of the antenna coil 11 is set to 30 Ω or less, preferably 10 Ω or less.

[0021] 1(c), the capacitive element 12 may be configured by a pair of electrode films 12a and 12b located on both sides of an insulating base 10a of the circuit board 10. The material of the electrode films 12a and 12b may be the same as the metal member used for the antenna coil 11. Alternatively, the capacitive element 12 may be a chip capacitor (for example, a film type).

[0022] The rectifier circuit 13 rectifies the input AC voltage signal and outputs it as a DC signal. The rectifier circuit 13 is, for example, a bridge circuit that performs full-wave rectification. Alternatively, the rectifier circuit 13 may be another circuit. The rectifier circuit 13 may also be a circuit that performs half-wave rectification, such as a circuit that simply uses a single diode, or a circuit that performs rectification in three or more phases. The two output terminals of the rectifier circuit 13 are connected to both ends (anode and cathode) of the organic EL light-emitting unit 21 by wiring 31 and 32, respectively.

[0023] The wirings 31 and 32 may be connected at least at one location via an anisotropic conductive film. Furthermore, the connection ends of the wirings 31 and 32 to the organic EL light-emitting unit 21 are connected using a conductive connecting member 33. The conductive connecting member 33 is, for example, an anisotropic conductive film, a conductive adhesive, or a conductive tape. An anisotropic conductive film is preferable because it requires a low temperature for thermocompression bonding and can reduce the thermal load on the organic EL light-emitting unit 21. The wirings 31 and 32 output the rectified power supply signal output by the rectifier circuit 13 to the light-emitting substrate 20 (organic EL light-emitting unit 21).

[0024] The anisotropic conductive film is a film in which conductive particles are dispersed in a binder. The conductive particles are, for example, metal cores such as gold, nickel, silver, or copper, or composite particles in which these metals are plated on resin cores such as acrylic resin or styrene resin. From the viewpoint of connection reliability, composite particles plated with metals such as nickel or gold are particularly preferred. The particle diameter is typically 3 to 5 μm. The binder is, for example, a thermoplastic resin such as polyamideimide, or an epoxy resin or phenolic resin. In particular, epoxy resin is preferred from the viewpoints of resin fluidity, connection reliability, cost, pot life, and the like. The anisotropic conductive film may also be one in which nickel fibers are oriented as a filler. When the conductive connecting member 33 is a conductive adhesive, the conductive adhesive may be a conductive paste containing the above components that has been bonded and solidified.

[0025] The integrated circuit 14 is connected to both ends of the antenna coil 11 between the antenna coil 11 and the rectifier circuit 13. The integrated circuit 14 operates using the acquired power, demodulating and processing the modulated signal to perform predetermined calculations, control operations, etc. The control operations may include transmitting signals to the outside. That is, the integrated circuit 14 may be for wireless communication using RFID (NFC, etc.). The external device to which the communication connection is made may be an IC card reader / writer. The operating voltage of the integrated circuit 14 is in a range not significantly different from the light-emitting voltage of the organic EL light-emitting unit 21, for example, in the range of 1 to 5 V. It is preferable that the integrated circuit 14 consumes less current.

[0026] Resistance elements R1 and R2 (impedance elements) are connected in series to the integrated circuit 14 and in parallel to the rectifier circuit 13 and the organic EL light-emitting unit 21. Resistance element R1 (part of the impedance element) is connected to one end of the integrated circuit 14, and resistance element R2 (an impedance element other than the part mentioned above) is connected to the other end of the integrated circuit 14 opposite the one end mentioned above. Resistance elements R1 and R2 reduce the amount of current to the integrated circuit 14. As a result, the current generated in the antenna coil 11 by electromagnetic induction is relatively more likely to flow to the organic EL light-emitting unit 21 via the rectifier circuit 13.

[0027] The resistive elements R1 and R2 may be dedicated resistors. Alternatively, the resistive elements R1 and R2 may be elements that increase resistance by locally narrowing the cross-sectional area (mainly the width) of a wiring pattern of a metal member formed on the insulating base 10a. In this case, the metal member may be made of the same material as the antenna coil 11 and the wiring 31 and 32. Furthermore, the resistive elements R1 and R2 may each be divided into multiple resistive portions (multiple resistive elements arranged in series and / or parallel).

[0028] FIG. 2 is a modified circuit diagram of the light emitting module 1. In FIG. Only one of the resistor elements R1 and R2 may be connected in series to the integrated circuit 14. In Fig. 2(a), the resistor element R2 is omitted. In Fig. 2(b), the resistor element R1 is omitted. Even with such a connection of the resistor elements R1 and R2, the power (current) supplied to the integrated circuit 14 can be reduced.

[0029] As described above, by connecting the capacitor 22 in parallel with the organic EL light-emitting unit 21 and supplying DC power from the rectifier circuit 13, the voltage of the organic EL light-emitting unit 21 rises above the light-emitting threshold, and the current increases, thereby increasing the light-emitting intensity (brightness). The larger the capacitance of the capacitor 22, the more effective it is. On the other hand, if the capacitance of the capacitor 22 becomes too high compared to the capacitance of the organic EL light-emitting unit 21, the current flowing through the organic EL light-emitting unit 21 will not increase, and this may even lead to a decrease in the current. Therefore, although not particularly limited, it is preferable that the capacitance of the capacitor 22 be between these values.

[0030] Furthermore, by arranging the resistor elements R1 and R2 in series with the integrated circuit 14 and in parallel with the rectifier circuit 13 and the organic EL light-emitting unit 21, the power supply to the organic EL light-emitting unit 21 increases, and the light emission intensity (brightness) thereof increases. In this case, the resistor elements R1 and R2 are set as large as possible within a range in which the input voltage to the integrated circuit 14 does not fall below the operating voltage described above. In consideration of the effect on the light emission of the organic EL light-emitting unit 21, it is preferable that the total impedance (here, the resistance value) of the resistor elements R1 and R2 be equal to or greater than the resistance value of the wiring resistance of the organic EL light-emitting unit 21.

[0031] 3 is a graph showing the results of measuring the luminance of the organic EL light-emitting unit 21 versus the capacitance of the capacitor 22 and the resistance of the resistor element R1. Here, the measurement results correspond to the capacitance of the capacitor 22 when the antenna coil 11 is wound four times, the capacitance of the capacitive element 12 is 40 pF, the size of the organic EL light-emitting unit 21 is 29 × 22 mm, and the equivalent parallel capacitance is approximately 100 nF.

[0032] In the graph shown in FIG. 3(a), the capacitance of the capacitor 22 is varied without the resistor R1. Measurement results show that the brightness of the organic EL light-emitting unit 21 increases when the capacitance of the capacitor 22 is approximately 1 / 1000 (0.1 nF) of the equivalent parallel capacitance. When the capacitance of the capacitor 22 reaches approximately the equivalent parallel capacitance (approximately 100 nF), the brightness saturates and becomes difficult to increase further. To achieve a certain increase in light intensity while keeping the size and weight of the capacitor 22 small, a capacitance of 1 / 1000 or more (more preferably 1 / 100 or more) and 1 / 20 or less of the equivalent parallel capacitance is preferable. Even at this level of capacitance, the capacitor 22 contributes to increasing the brightness of the organic EL light-emitting unit 21. On the other hand, if you want to ensure sufficient brightness rather than limit the size of the capacitor 22, a capacitance of 1 / 20 or more and 10 times or less (more preferably 1 time or less) the equivalent parallel capacitance is preferable.

[0033] In the graph shown in Figure 3(b), the resistance value of resistor element R1 is changed without placing capacitor 22. Measurement results show that the brightness of organic EL light-emitting unit 21 increases as the resistance value of resistor element R1 increases. The resistance value saturates at about 50 Ω, and it becomes difficult to become brighter than this.

[0034] In this way, by including at least one of the capacitor 22 and the resistor elements R1 and R2 in the circuit, the brightness of the organic EL light-emitting unit 21 can be increased easily and effectively.

[0035] Next, the positional relationship of each component in the light-emitting module 1 will be described. In the example of FIG. 1( a), when the circuit board 10 is viewed from above (perpendicular to the circuit pattern surface including the surface (power receiving surface) on which the coil wiring of the antenna coil 11 is located), the capacitive element 12, rectifier circuit 13, and integrated circuit 14 are located inside the annular antenna coil 11. Meanwhile, the organic EL light-emitting unit 21 and capacitor 22 are located outside the antenna coil 11. This allows the organic EL light-emitting unit 21 to suppress the effects of electromagnetic induction in the circuit (wiring) of the organic EL light-emitting unit 21 due to changes in the electromagnetic field (magnetic flux) that the antenna coil 11 is subjected to. Furthermore, the insulating base 10a of the circuit board 10 on which the antenna coil 11 is located and the base material of the light-emitting substrate 20 may be different and suitable for each. The specific wiring locations are not limited to those shown in the figure. The wiring may be located on both sides and / or inside the insulating base 10a, as appropriate.

[0036] Alternatively, the positional relationship between the components in the light-emitting module 1 can be changed in various ways. 4 to 6 are diagrams showing modified examples of the positional relationship of each component in the light-emitting module 1. In FIG. For example, as shown in FIG. 4(a), the organic EL light-emitting unit 21 and / or the capacitor 22 may be located within (inside) the loop of the antenna coil 11. In this case, the organic EL light-emitting unit 21, the antenna coil 11, the capacitive element 12, the rectifier circuit 13, the integrated circuit 14, and the resistive elements R1 and R2 may be located on the same insulating substrate. As long as the area of ​​the organic EL light-emitting unit 21 is not particularly large compared to the area of ​​the antenna coil 11 (in this case, less than half), it will not significantly affect either the antenna coil 11 or the organic EL light-emitting unit 21. Furthermore, by integrating the organic EL light-emitting unit 21 and the capacitor 22 (particularly the multilayer ceramic capacitor) with other components on the circuit board 10, design freedom and flexibility are improved. Therefore, a light-emitting module 21 with such a structure is easy to manufacture.

[0037] 4(b), the organic EL light-emitting unit 21 may be located on (overlaps with) the loop of the antenna coil 11, with a portion inside the loop and another portion outside the loop. In this case, the light-emitting surface of the organic EL light-emitting unit 21 may be located on the opposite side of the insulating substrate from the side where the antenna coil 11 is located. In this way, all components can be arranged on a single insulating base 10a, which allows for unification of the manufacturing process. Furthermore, the space inside the antenna coil 11 is effectively utilized, which facilitates miniaturization.

[0038] 5(a), the organic EL light-emitting unit 21 and the capacitor 22 may be positioned so as to overlap each other in a planar view. In this case, as shown in the cross-sectional view of FIG. 5(b), the organic EL light-emitting unit 21 and the capacitor 22 may be positioned on opposite sides of the base material of the light-emitting substrate 20. The organic EL 21 emits light toward the side exposed to the outside. That is, the capacitor 22 is positioned on the side opposite the light-emitting surface of the organic EL 21. This allows the area of ​​the light-emitting substrate 20 to be reduced. The sides on which the organic EL light-emitting unit 21 and the capacitor 22 are positioned may be interchanged. Depending on how the light-emitting module 1 is used, it is preferable that the organic EL light-emitting unit 21 be positioned on the side that allows the user to visually recognize the light-emitting state when the light-emitting surface of the organic EL light-emitting unit 21 emits light.

[0039] 6(a), at least some (here, all) of the rectifier circuit 13, the integrated circuit 14, and the resistive elements R1 and R2 may be located outside the loop of the antenna coil 11. In this case, the capacitive element 12 may also be located outside the loop of the antenna coil 11.

[0040] 6(b), the capacitor 22 may be located on the circuit board 10. In this case, the organic EL light-emitting unit 21 may be attached separately to the circuit board 10. Placing the capacitor 22 on the circuit board 10 in this manner is also possible in the arrangements shown in FIGS. 1 and 5.

[0041] Furthermore, when the circuit board 10 and the light emitting board 20 are separate bodies as in FIGS. 1, 5, and 6, the circuit board 10 and the organic EL light emitting section 21 do not need to be directly connected. FIG. 7 is a diagram showing a modified example of the connection between the circuit board 10 and the light emitting board 20 of the light emitting module 1. In FIG. In this modification, the circuit board 10 and the light-emitting board 20 are connected by electric cables 31a and 32a. The electric cables 31a and 32a are coated copper wires, which are copper wires or the like coated with an insulating material (such as vinyl resin). The two electric cables 31a and 32a may be further bundled together. The electric cables 31a and 32a can be bent, twisted, rotated, and the like more easily than the circuit board 10, such as an FPC. The lengths of the electric cables 31a and 32a can be set arbitrarily. That is, even with the same combination of circuit board 10 and light-emitting board 20, the lengths of the electric cables 31a and 32a can be easily changed. In this case, the coated copper wires may be connected and fixed to the circuit board 10 and the light-emitting board 20 with solder 34 or the like. Fixing with solder 34 facilitates disassembly of the light-emitting module 1 and partial replacement of the circuit board 10, the light-emitting board 20, or the electric cables 31a and 32a themselves.

[0042] Furthermore, even when the circuit board 10 and the light-emitting board 20 are directly connected as described above, the size of the circuit board 10 can be adjusted according to the distance that is desired to be secured between the antenna coil 11 and the organic EL light-emitting unit 21. In this case, the relay portion of the circuit board 10 that is outside the loop of the antenna coil 11 and that is connected to the light-emitting board 20 may be narrower in width than the portion where the antenna coil 11 is located.

[0043] As described above, the light-emitting module 1 of this embodiment includes a light-emitting unit having an organic EL light-emitting unit 21, an antenna coil 11 that receives power wirelessly from an external device, an integrated circuit 14 that is connected to the antenna coil 11 and operates using the power received by the antenna coil 11, a rectifier circuit 13 that rectifies the power received by the antenna coil 11 and outputs the rectified power to the light-emitting unit, and resistor elements R1 and R2 that serve as impedance elements and are located in series with the integrated circuit 14 and in parallel with the rectifier circuit 13 and the organic EL light-emitting unit 21. In this way, the light-emitting module 1 suppresses the current flowing through the integrated circuit 14 using the resistor elements R1 and R2. This allows the light-emitting module 1 to more efficiently supply a current related to the induced electromotive force of the antenna coil 11 to the organic EL light-emitting unit 21, thereby increasing the light-emitting intensity of the organic EL light-emitting unit 21.

[0044] Furthermore, the resistive element may be connected only to one end of the integrated circuit 14. That is, only one of the resistive elements R1 and R2 may be connected to the integrated circuit 14. Even if only one resistive element is provided, and whether that resistive element is R1 or R2, the current value of the integrated circuit 14 does not change, and signal demodulation is not affected. Therefore, in this light-emitting module 1, the resistive elements can be collectively formed on one side of the circuit board 10.

[0045] Alternatively, a portion of the impedance element (resistance element R1) may be connected to one end of the integrated circuit 14, and another impedance element (resistance element R2) may be connected to the other end opposite the one end. No matter how the resistance elements R1 and R2 are connected, as long as they are connected in series with the integrated circuit 14 and in parallel with the organic EL light-emitting unit 21, there is no problem as long as the required voltage and current are maintained as described above. Therefore, the light-emitting module 1 may be formed with the resistance elements separated into two locations on the circuit board 10 by appropriately utilizing the space. Even if they are separated on both sides on the circuit, the resistance elements R1 and R2 may be positioned side by side on the insulating base 10a.

[0046] Furthermore, the total impedance (resistance value) of the resistor elements R1 and R2 is equal to or greater than the resistance value of the wiring resistance of the organic EL light-emitting unit 21. This makes it possible to more effectively reduce the current flowing through the resistor elements R1 and R2 and the integrated circuit 14 compared to the current flowing to the organic EL light-emitting unit 21. Therefore, the light-emitting module 1 can easily increase the brightness of the organic EL light-emitting unit 21.

[0047] The light-emitting unit may also be located outside the antenna coil 11. This separates the light-emitting unit itself from the operating parts of electromagnetic induction, making the wiring of the light-emitting unit less susceptible to the effects of magnetic flux changes related to electromagnetic induction. On the other hand, if the insulating base 10a of the circuit board 10 is an FPC or the like, the antenna coil 11 and the organic EL light-emitting unit can be easily folded 180 degrees as needed to overlap each other. Therefore, in this case, space can be saved when the light-emitting module 1 is in use, even if they are not all assembled onto a single board during the manufacturing stage of the light-emitting module 1.

[0048] Alternatively, the light emitting portion may be located inside the antenna coil 11. This allows the space inside the antenna coil 11 to be used effectively, thereby enabling the light emitting module 1 to be made smaller.

[0049] Furthermore, the light emitting unit has a portion located on the antenna coil 11, and part of it may be located outside the antenna coil 11, and another part may be located inside the antenna coil 11. Depending on the size of the antenna coil 11 and the area occupied by other components placed inside the antenna coil 11, part of the light emitting unit may extend outside the annular range of the antenna coil 11. By arranging the light emitting unit so that it is only within the range of the antenna coil 11, it is possible to efficiently utilize the top surface of the insulating base 10a (surface including the front and back sides).

[0050] Furthermore, the rectifier circuit 13, the integrated circuit 14, and the resistor elements R1 and R2 may be located either outside or inside the antenna coil 11. By locating these inside, the space within the loop of the antenna coil 11 can be effectively utilized, and the circuit board 10 can be made smaller. On the other hand, by locating these outside, overlapping of wiring can be reduced and each component can be easily arranged.

[0051] Alternatively, some of the rectifier circuit 13, the integrated circuit 14, and the resistor elements R1 and R2 may be located inside the wireless power receiving unit, and the rest may be located outside the wireless power receiving unit. That is, depending on the space allocation of the circuit board 10, the rectifier circuit 13, the integrated circuit 14, and the resistor elements R1 and R2 may be appropriately distributed across the inside and outside of the antenna coil 11. This allows the space on the circuit board 10 to be used appropriately.

[0052] Furthermore, the resistive elements R1 and R2 may be made of the same material as the conductor pattern of the metal member formed on the insulating base 10a as the antenna coil 11. Therefore, the antenna coil 11 and the resistive elements R1 and R2 can be easily formed together and positioned appropriately on the insulating base 10a. This allows the light-emitting module 1, particularly the circuit board 10, to be easily obtained at low cost.

[0053] Furthermore, the wiring connecting the light-emitting unit and the antenna coil 11 may be flexible wiring. By making the wiring bendable, it is possible to appropriately orient the wiring between the components related to power supply and signal reading and the components related to light emission. This further improves user convenience.

[0054] The wiring may also include an electric cable. An electric cable allows for more flexible changes in the position and orientation of the light-emitting unit. Furthermore, electric cables are often easier to attach and detach than connections between or within boards, making it easier to perform partial adjustments and replacements.

[0055] The wiring may also include a portion located on a flexible substrate, and the substrate may be an FPC. By being able to bend the wiring together with the substrate, concerns about the durability of the connection portion of the wiring, which is relatively prone to weakening in connection strength, can be alleviated.

[0056] At least one of the wirings may be connected by an anisotropic conductive film, which requires a low temperature for thermocompression bonding, thereby reducing the thermal influence on the organic EL light-emitting unit 21.

[0057] At least one of the wirings may be connected with a conductive adhesive. Depending on the joining location and the joining object, the joining can be easily achieved by using a conductive adhesive (paste).

[0058] The present invention is not limited to the above-described embodiment, and various modifications are possible. For example, the capacitor 22 described in the above embodiment does not need to be included. That is, as shown in Fig. 3(b), the light-emitting module 1 can increase the brightness of the organic EL light-emitting unit 21 using only the resistor element R1 (and R2).

[0059] In the above embodiment, the light emitting module 1 is described as including one integrated circuit 14, but this is not limiting. The light emitting module 1 may include a plurality of integrated circuits 14.

[0060] Furthermore, in the above embodiment, the resistive elements R1 and R2 are connected in series to the integrated circuit 14. However, other elements, such as a coil (inductive element) or a capacitor (capacitive element), may be used as long as they increase the impedance. These elements do not need to be dedicated electronic components, but may be formed by wiring patterns formed on the insulating base 10a or electrodes sandwiching the insulating base 10a itself. In these cases, the magnitude of the impedance need only be determined within a range that allows demodulation of the input signal. Furthermore, in these cases, the magnitude of the impedance depends on the frequency of the signal. Therefore, the impedance design may be based on the frequency of the external magnetic flux fluctuation to be received (such as that associated with the RFID (NFC)).

[0061] Furthermore, the capacitive element 12 does not need to be provided in the circuit of the light-emitting module 1, as long as there is no problem with the signal output from the antenna coil 11 at an appropriate amplitude (induced electromotive force).

[0062] In the above embodiment, the RFID frequency used for NFC in the HF band has been described as an example, but the present invention is not limited to this. It may be applied to a lower LF band (135 kHz) or a higher UHF band (860-960 MHz). In this case, the parameters of each element may be adjusted appropriately.

[0063] In the above embodiment, when the capacitor 22 is located outside the circuit board 10, it is described as being on the same substrate as the organic EL light-emitting unit 21, but this is not limited to this. The substrate on which the capacitor 22 is located and another substrate on which the organic EL light-emitting unit 21 is located may be joined together.

[0064] Furthermore, the structures, configurations, and positional relationships thereof shown in the above-described embodiments and modifications may be arbitrarily combined with those shown in other embodiments or modifications within the scope of not contradicting each other. In addition, the specific configurations, contents and procedures of the processing operations, etc. shown in the above embodiments can be modified as appropriate without departing from the spirit of the present invention. The scope of the present invention includes the scope of the invention described in the claims and its equivalents. [Explanation of symbols]

[0065] 1 Light-emitting module 10 Circuit Board 10a Insulating substrate 11 Antenna coil 12 Capacitive elements 12a, 12b electrode membrane 13 Rectifier circuit 14 Integrated Circuits 20 Light-emitting substrate 21 Organic EL light-emitting section 22 Capacitor 31, 32 Wiring 31a, 32a Electrical cables 33 Conductive connecting member 34 Solder R1, R2 Resistor elements

Claims

1. a light-emitting section having an organic EL element; a wireless power receiving unit that receives power wirelessly from an external device; an integrated circuit connected to the wireless power receiving unit and operating on power received by the wireless power receiving unit; a rectifier circuit that rectifies the power received by the wireless power receiving unit and outputs the rectified power to the light emitting unit; an impedance element located in series with the integrated circuit and in parallel with the light emitting unit and the rectifier circuit; A light emitting module comprising:

2. 2. The light-emitting module according to claim 1, wherein the impedance element is connected only to one end of the integrated circuit.

3. 2. The light emitting module according to claim 1, wherein a part of the impedance element is connected to one end of the integrated circuit, and the other part of the impedance element is connected to the other end opposite to the one end of the integrated circuit.

4. 2. The light-emitting module according to claim 1, wherein the impedance of the impedance element is equal to or greater than the resistance of the wiring resistance of the light-emitting section.

5. The light-emitting module according to claim 1 , wherein the light-emitting unit is located outside the wireless power receiving unit.

6. The light-emitting module according to claim 1 , wherein the light-emitting unit is located inside the wireless power receiving unit.

7. The light-emitting module according to claim 1 , wherein the light-emitting unit has a portion located above the wireless power receiving unit, a part of which is located outside the wireless power receiving unit.

8. 2. The light-emitting module according to claim 1, wherein the light-emitting unit has a portion located above the wireless power receiving unit, a part of which is located inside the wireless power receiving unit.

9. The light-emitting module according to claim 1 , wherein the rectifier circuit, the integrated circuit, and the impedance element are located outside the wireless power receiving unit.

10. The light-emitting module according to claim 1 , wherein the rectifier circuit, the integrated circuit, and the impedance element are located inside the wireless power receiving unit.

11. 2. The light-emitting module according to claim 1, wherein some of the rectifier circuit, the integrated circuit, and the impedance element are located inside the wireless power receiving unit, and the remaining parts are located outside the wireless power receiving unit.

12. 2. The light-emitting module according to claim 1, wherein the impedance element is made of the same material as the wireless power receiving section.

13. 2. The light-emitting module according to claim 1, wherein the wiring connecting the light-emitting unit and the wireless power receiving unit is a flexible wiring.

14. 14. The light emitting module of claim 13, wherein the wiring includes an electrical cable.

15. The light-emitting module according to claim 13 , wherein the wiring includes a portion located on a flexible substrate.

16. The light emitting module according to claim 13 , wherein the wiring includes wiring on a flexible printed circuit board.

17. 14. The light-emitting module according to claim 13, wherein at least one of the wirings is connected by an anisotropic conductive film.

18. 14. The light-emitting module according to claim 13, wherein at least one of the wirings is connected with a conductive adhesive.

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