JP2002289924A - Light-emitting element, illuminator, and display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the size of a light-emitting element, having a light-emitting section which emits light, when at least a voltage or current is supplied to the section. SOLUTION: Electrodes 11 and 12, which are insulated from each other by inserting an insulation material 13 in between are laminated together into a single body. The upper end sections 11a and 12a of the electrodes 11 and 12 are given the functions of holding the light-emitting section 14, and the section 14 is held on the holding sections 11a and 12a via another insulating material 15. The light-emitting section 14 is connected to the electrodes 11 and 12 via bonded wires 16 and 17 and emits light, when a current or voltage is supplied or applied across the electrodes 11 and 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light-emitting device, a lighting device, and a display device, and more particularly, to a small-sized light-emitting device having a high light-condensing effect, a high-definition planar lighting device using the light-emitting device, and a light-emitting device. The present invention relates to a high-definition and low-cost display device using a lighting device.

[0002]

2. Description of the Related Art Various researches and developments have been made on display devices in order to realize small and high-definition displays.
Among them, in a direct-view display device, it is important to reduce the size of the light-emitting element and arrange it with high definition when viewing the light-emitting element directly. Is an important issue. Further, in a projection type display device, high definition of a light valve and downsizing of a light source are important issues. Here, a light source in a display device in which a light emitting element is directly viewed and a display device in which a light emitting element is projected will be described. As a light emitting element serving as a light source, a light emitting diode (hereinafter, referred to as an LED) will be described as a representative. FIG. 12 is a cross-sectional view schematically showing a configuration of a conventional light emitting element using LEDs, and shows a case where two LEDs are mounted in one package.
The LED as a light emitting element shown in FIG. 12 is composed of an electrode 1 connected to the anode and an electrode 2 connected to the cathode.
A book electrode (also called a lead frame) is required.

This LED has an electrode 2 corresponding to a cathode.
The light emitting unit 3 is mounted on one of the
After electrically connecting the electrodes 1, 2, and
The light emitting section 3 and the wire bonding 4 and 5 are made of a translucent resin 6.
It is sealed by filling it with a mold 7. Since such a conventional lamp-shaped LED uses two separate electrodes 1 and 2 respectively,
The ED itself had to grow. Further, the patent publication of Japanese Patent No. 2821064 also describes the miniaturization of LEDs. LE described in this publication
In D, two kinds of LEDs are stored in one package,
Mounted by wire bonding. That is, in the LED of the above-mentioned patent publication, at least two light emitting diode chips that emit light at different wavelengths are attached and wired to a lead frame, and the light emitting diode chip and the lead frame are covered with a rectangular transparent resin. In the light-emitting diode lamp, the size of the LED is reduced by securing the distance between the lead frames by providing the lead frame on a substantially diagonal line of the rectangular body.

[0004]

However, in the case of the LED described in this patent publication, since two LEDs are mounted in one package, three independent lead frames are used and one package is used. When mounting on a substrate, it is necessary to perform three wirings. In addition, when two-dimensionally arranging or simply increasing the number of mountings, it is inevitable that the cost of mounting work, board design, and the like increase and the work becomes complicated. Further, it cannot be said that any of the above-described conventional techniques has fundamentally reduced the size of the element itself. The present invention has been made in view of the above circumstances, and can reduce the size of a light-emitting element, can be formed in a high-definition and planar shape as a lighting device, and has a high-definition and high-cost light-emitting element as a display device. It is an object of the present invention to provide a light-emitting element, a lighting device, and a display device that can reduce the amount of light. An object of claim 1 of the present invention is to provide a light-emitting element which can be miniaturized by providing an electric connection means for supplying a voltage or a current to the light-emitting unit with a function of holding the light-emitting unit. Is to do. An object of claim 2 of the present invention is to provide a light-emitting element that can achieve downsizing.

[0005] It is an object of the present invention to provide a light emitting device capable of improving light use efficiency. An object of claim 4 of the present invention is to provide a light emitting device capable of improving light use efficiency. An object of claim 5 of the present invention is to provide a light emitting element which can be mounted on a substrate and connected to a driving circuit at low cost and easily. An object of claim 6 of the present invention is to provide a light emitting element which can be miniaturized and which is easy to mount. A further object of the present invention is to provide a light emitting element which can be miniaturized and can be easily mounted even in a light emitting portion formed by current injection formed on an insulating substrate. An object of claim 8 of the present invention is to provide a planar illumination device capable of performing high-definition planar illumination. An object of a ninth aspect of the present invention is to provide a display device with high definition, low mounting cost and easy manufacture. An object of a tenth aspect of the present invention is to provide a bright, small-sized, low-cost projection type display device as compared with a conventional one.

[0006]

According to a first aspect of the present invention, there is provided a light-emitting device according to the present invention, which includes a light-emitting portion that emits light by supplying at least a voltage or a current, and an electrode that electrically connects to the light-emitting portion. Electrical connection means having a function and a function of independently holding the light emitting unit. According to a second aspect of the present invention, in the light-emitting device according to the present invention, the electrical connection means including the required number of electrodes of the light-emitting portion is formed of a conductive material having at least mutual insulation and integrated. And According to a third aspect of the present invention, there is provided a light emitting device, wherein the holding section for holding the light emitting section is provided with a reflection function of reflecting light emitted from the light emitting section.
The light emitting element according to the present invention described in claim 4 is characterized in that the side of the holding section where the light emitting section is provided is covered with a light transmitting material.

In the light emitting device according to the present invention, at least one electrode is electrically connected to the light emitting portion on a side opposite to a portion for holding the light emitting portion in the portion for performing electrical connection. The electrode is electrically connected to a side surface made of a conductive material while being connected, and the remaining electrodes are electrically connected to a conductive material on the inside which is electrically insulated from the conductive material on the side surface. . The light-emitting element according to the present invention described in claim 6 has a structure in which a light-emitting layer having a function of emitting light by injecting a current is stacked on a conductive substrate, and at least one light-emitting layer is formed on the stacked light-emitting layer. Providing a portion that performs an electrical connection means, connected to one of the electrodes via a conductive material, or having an electrical connection means to connect to the electrode using wire bonding on the conductive material and the light emitting layer, It is characterized in that a means for insulating at least between different electrodes is provided on a surface in contact with the holding portion. 8. The light-emitting device according to claim 7, wherein the light-emitting portion has a light-emitting layer that emits light by injecting a current into at least an insulating material, and at least one light-emitting layer is provided on the light-emitting layer. And electrical connection means, and the electrical connection means and the light emitting unit are connected by wire bonding.

[0008] According to a second aspect of the present invention, there is provided a spread illuminating apparatus according to the present invention, wherein at least a light emitting portion that emits light by supplying a voltage or a current, and a portion that holds the light emitting portion out of portions that are electrically connected. On the opposite side, at least one electrode is electrically connected to the light emitting portion and electrically connected to a side surface made of a conductive material, and the other electrode is electrically insulated from the conductive material on the side surface. And a light-emitting element having an electrical connection means electrically connected to the conductive material on the inside.
According to a ninth aspect of the present invention, there is provided a display device comprising three color light emitting diodes that emit red, green, and blue light by supplying at least a voltage or a current.
A light-emitting portion formed by a light-emitting diode arranged two-dimensionally with a pixel as a unit, and at least one of the electrodes for electrical connection is opposite to a portion holding the light-emitting portion. While being electrically connected to the light emitting portion, it is electrically connected to the side surface made of a conductive material, and the remaining electrodes are electrically connected to the inside conductive material which is electrically insulated from the conductive material on the side surface. An electrical connection unit to be connected, and a unit for individually turning on and off each of the light emitting diodes, and comprising an on / off controlled light emitting diode configured to display an image by blinking. I have.

According to a tenth aspect of the present invention, there is provided a projection type display device, comprising: a light-emitting portion comprising a light-emitting diode in which light-emitting layers for emitting red, green and blue light are respectively supplied by supplying at least a voltage or a current. On the other side of the portion that performs the electrical connection, the opposite side of the portion that holds the light emitting portion, at least one electrode is electrically connected to the light emitting portion, and is electrically connected to a side surface made of a conductive material, The other electrode is a planar illumination having a light emitting element mounted on a substrate, the light emitting element having an inner conductive material electrically insulated from the conductive material on the side surface and an electrical connection means electrically connected thereto. It is characterized by comprising a light source by the device and an optical system for condensing light generated from the light source and projecting the light to a predetermined portion.

[0010]

In other words, the light emitting device according to the first aspect of the present invention has a light emitting portion that emits light by supplying at least a voltage or a current, and has a function as an electrode for making an electrical connection to the light emitting portion. In particular, the provision of the electric connection means having a function of holding the light-emitting portion makes it possible to reduce the size of the light-emitting element. The light-emitting device according to the second aspect of the present invention is characterized in that the light-emitting portion emits light by constructing and integrating at least electrical connection means comprising the required number of electrodes with conductive materials having at least insulating properties from each other. The element can be reduced in size. In the light emitting device according to the third aspect of the present invention, the use efficiency of light can be increased by providing the holding portion with a reflection function of reflecting light emitted from the light emitting portion. In the light emitting device according to the invention of claim 4 of the present invention, the use efficiency of light emitted from the light emitting unit can be enhanced by covering the light emitting unit side with the light transmitting material. .

In a light emitting device according to a fifth aspect of the present invention, at least one electrode is electrically connected to the light emitting portion on a side opposite to a portion for holding the light emitting portion among the portions for electrical connection. And the other electrode is electrically connected to the conductive material on the inside, which is electrically insulated from the conductive material on the side surface. And the connection to the drive circuit can be made cheap and easy. Claim 6 of the present invention
The light emitting device according to the invention is characterized in that a light emitting layer having a function of emitting light by injecting a current is stacked on a conductive substrate, and at least one or more electrical connection means is provided on the stacked light emitting layer. A portion to be provided is provided, and one of the electrodes is connected to the electrode via a conductive material, or the conductive material and the light-emitting layer have electrical connection means for connecting to the electrode by using wire bonding. Providing at least a means for insulating between different electrodes enables a light-emitting portion formed on a conductive substrate by current injection to be reduced in size.

In a light emitting device according to a seventh aspect of the present invention, the light emitting portion has at least one light emitting layer which emits light by injecting a current into an insulating material, and at least one light emitting layer is provided on the light emitting layer. A light-emitting element that is small in size and easy to mount even with a light-emitting portion formed on an insulating substrate by current injection by providing an electric connection means and connecting the light-emitting portion to the light-emitting portion by wire bonding. Can be realized. The planar lighting device according to the invention of claim 8 of the present invention has a light emitting portion that emits light by supplying at least a voltage or a current, and a portion of the portion that performs electrical connection opposite to a portion that holds the light emitting portion. And at least one electrode is electrically connected to the light emitting unit,
An electrical connection means electrically connected to the side surface made of a conductive material, and the remaining electrodes electrically connected to the inside conductive material electrically insulated from the conductive material on the side surface; By mounting the light emitting element provided on the substrate,
High-definition planar illumination can be realized.

In the display device according to the ninth aspect of the present invention, by supplying at least a voltage or a current, one pixel is constituted by light emitting diodes of three colors emitting red, green and blue light, respectively. At least one electrode is electrically connected to the light emitting unit on the opposite side of the part that holds the light emitting unit among the light emitting units formed by the light emitting diodes arranged two-dimensionally as one unit and the part that performs the electrical connection. An electrical connection means electrically connected to the side surface made of a conductive material, and the remaining electrodes electrically connected to the inside conductive material electrically insulated from the conductive material on the side surface. And means for individually turning on and off each of the light-emitting diodes, and displaying an image by blinking the light-emitting diodes to be turned on and off, thereby achieving high definition. Implementation cost is low and manufacture can be realized easily direct view type display device.
The projection type display device according to the tenth aspect of the present invention is configured such that a light emitting unit including a light emitting diode in which light emitting layers emitting red, green, and blue light are laminated by supplying at least a voltage or a current, respectively, is electrically connected. Out of the part that holds the light emitting unit, at least one electrode is electrically connected to the light emitting unit,
The remaining electrode has an electrical connection means electrically connected to the inner conductive material electrically insulated from the conductive material on the side surface and electrically connected to the conductive material side surface. By providing a light source of a planar lighting device in which a light emitting element is mounted on a substrate, and an optical system for condensing light generated from the light source and projecting the light to a predetermined portion, the size is smaller than a conventional one. In addition, a low-cost and bright projection display device can be realized.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a light emitting device, a lighting device, and a display device according to the present invention will be described in detail based on embodiments with reference to the drawings. FIG. 1 is a perspective view showing an external configuration of a light emitting device according to a first embodiment of the present invention,
FIG. 2 is a cross-sectional view illustrating the configuration of the light emitting device. Before explaining with reference to FIGS. 1 and 2, first, the outline of the features of the first embodiment of the light emitting device of the present invention will be described.
The light emitting device of the first embodiment has a small light emitting device by using a holding portion as a holding mechanism for the light emitting device as an electrical connection means for electrically connecting to a light emitting portion which is a light emitting mechanism. It will be realized. As a light-emitting element according to the present invention, by applying a voltage or flowing a current,
Any element that emits light, that is, an element that emits light by supplying a voltage or a current can be used. Specifically, the light emitting portion as a light emitting element is a current injection type LED,
An organic EL, an electroluminescent inorganic EL, or the like can be used. Considering controllability, stability and lifetime, LED
Is preferred.

Here, as the light emitting element of the first embodiment, an LED will be described as an example. This LED is
2, as shown in the conventional example, the electrode 2 connected to the cathode mounts the light emitting portion 3 and is electrically connected by wire bonding 4, 5, etc., and the two electrodes 1 and 2 are separately Because of the connection, miniaturization of the shape of the LED itself has been hindered. On the other hand, in the first embodiment, the size of the light emitting element is reduced, and FIG.
As shown in FIGS. 2A and 2B, two types of electrodes 11 and 12 (made of a conductive material such as a metal) are attached to each other by sandwiching an insulating material 13 such as a mica plate and bonding them together. Integrally forming the electrical connection means, and grinding into a flat surface to mount the light emitting unit 14 on one end (the upper part in FIGS. 1 and 2) of the electrical connection means,
a and 12a. This holding part 11
a, a light emitting portion 14 (L
(ED chip) is bonded and held. A prototype LED having a diameter of 1.5 mm was realized based on such a configuration.

When a lighting test of a prototype of the LED having a diameter of 1.5 mm was performed, it was confirmed that the LED operates normally. Therefore, the size can be reduced to half of the diameter of the conventional commercial product. The electrodes 11 and 12 as the electrical connection means are thus made of the insulating material 1.
3 while holding the light-emitting unit 14 at the top while maintaining the insulating properties.
By having both of the light emitting elements 12a, the size of the light emitting element can be reduced. The light emitting section 14 is connected to the electrodes 11 and 12 via wire bondings 16 and 17. The insulating material 15 used for the light emitting section 14
Is unnecessary when the side of the light emitting section 14 in contact with the electrodes 11 and 12 is insulative. On the other hand, when both ends of the light emitting section 14, that is, the sides in contact with the electrodes 11 and 12 respectively expose the electrode portions required for light emission, the mounting is performed face down to perform wire bonding 16 and 17.
Can be omitted, and the process can be simplified.

In this case, it is preferable that a horizontal surface is formed in the electrode portion for performing face-down mounting. When one of the electrodes required for the light emitting unit 14 is formed on the substrate (not shown) of the light emitting unit 14 and the other is formed on the substrate (not shown) of the light emitting unit 14, one of the electrodes is used. On the side connected face-down and in contact with the other electrode, an insulative material is provided on the electrodes 11 and 12 or on a corresponding portion of the light emitting section 14, and the connection can be made by wire bonding. Regarding the shape of the holding portions 11a and 12a, a portion where electrical connection is made by the electrodes 11 and 12 has a mechanism for holding the light emitting portion 14, and the electrodes necessary for the light emitting portion 14 are integrated with each other while maintaining insulation from each other. Although the shape is not limited except that the light emitting portion 14 is held, the portion holding the light emitting portion 14 is more preferably
By forming the entire structure 2a, the heat capacity of the holding unit is increased, and the temperature rise of the light emitting unit 14 can be prevented. The method of division does not impose any restrictions other than the integration while maintaining the insulation (corresponding to claim 2).

Next, a description will be given of a second embodiment of the light emitting device according to the present invention. FIG. 3 is a perspective view showing the configuration of the second embodiment. In the second embodiment, the light emitting section 1 is provided on the holding sections 11a and 12a of the electrical connection means.
4 illustrates a case in which a mechanism for reflecting light emitted from the light source 4 is provided. By providing the reflecting mechanism in the holding units 11a and 12a, the light emitted from the light emitting unit 14 can be collected before diffusing from the light emitting unit 14. In the embodiment shown in FIG. 3, the holding unit 11 holding the light emitting unit 14
The case where a and 12a are parabolic shapes is illustrated (in FIG. 3, the shape of the surface is different from the actual shape and is schematically shown). In this case, the light emitting unit 14 is mounted near the focal position of the paraboloid. The electrodes 11 and 12 have an insulating property mutually with the insulating material 13 interposed therebetween. The holding surfaces of the holding portions 11a and 12a for holding the light emitting portion 14 on the upper surfaces of the electrodes 11 and 12 are formed as paraboloids as described above. The light-emitting portion 14 can be placed near the focal point of the paraboloid by adjusting the thickness of the insulating material 15.

As is clear from FIG. 3, also in the second embodiment, the electrical connection means by the electrodes 11 and 12 which are electrically insulated from each other with the insulating material 13 interposed therebetween are integrated. Holding portion 11a on the upper surface of the electrical connection means,
The side on which the light emitting portion 14 of 12a is held and mounted is formed on a paraboloid of revolution, and an LED chip is mounted as the light emitting portion 14 in the same manner as in the first embodiment. The connection between the light emitting unit 14 and the electrodes 11 and 11 is performed. When a lighting test of the light emitting unit 14 according to the LED of the prototype based on the second embodiment was performed,
It was confirmed that it works properly. Further, the LED on which the conventional light emitting element shown in FIG.
When the light emission characteristics of the LED according to the second embodiment were compared with those of the LED according to the second embodiment, only the diffused light could be obtained from the light emitting unit in the conventional light emitting element, whereas the light emission according to the second embodiment was not obtained. The light-collecting characteristic of about 80% was obtained from the device within a radiation angle of 60 degrees. For this reason, by providing the surface on which the light emitting unit 14 is mounted with reflection characteristics, the light emitting unit 14
It was found that it was possible to condense the light generated from the light. Also in this case, as compared with the commercially available light emitting device, as in the case of the first embodiment, a reduction in size by half in diameter could be realized.

Next, a third embodiment of the light emitting device of the present invention will be described. In the third embodiment, the light-emitting portion side of the holding portion that holds the light-emitting portion is light-transmitting (light-transmitting).
By covering with a material having the above, a portion for connecting the light emitting portion and the electrode is protected. As the light-transmitting material, a transparent epoxy resin or the like can be used. Further, by using this light-transmitting material, an optical component (a condensing lens or the like) for condensing light can be provided on the light emitting portion. In this case, it is preferable that the light condensing can be performed more efficiently by combining with the holding portion having the reflection function according to the second embodiment (corresponding to claim 4). . FIG. 4 is a perspective view showing a configuration of a third embodiment of the light emitting device according to the present invention. As is clear from the comparison of FIG. 4 with FIG. 3, FIG. 4 shows that the mold body 18 in which the connection portion between the light emitting portion 14 and the electrodes 11, 12 is covered with a transparent epoxy resin is added to the configuration of FIG. Have been. Here, the third embodiment will be described in further detail. As the light emitting section, the light emitting section shown in FIG. 3 is used.

That is, there are holding portions 11a and 12a,
Electrode 1 electrically insulated from each other via insulating material 13
1, 12 and the light emitting unit 14 are integrally bonded,
Between the light emitting portion and the electrode 14, the electrode 11 and the electrode 12,
They are connected by wire bonding 16 and 17, respectively. The light emitting unit 1 is provided on the holding units 11a and 12a of the electrical connection unit.
After mounting 4, a transparent epoxy resin, which is a translucent material, is injected into the light emitting unit 14 side to form a molded body. As described above, when a light-emitting element in which a transparent epoxy resin was molded at a connection portion between the light-emitting portion 14 and the electrodes 11 and 12 was prototyped and a lighting test was performed, it was confirmed that the light-emitting element operates normally. A comparison between the characteristics of the light-emitting element prototyped based on the light-emitting element shown in FIG. 4 and the characteristics of the conventional light-emitting element shown in FIG. 12 shows that the light-emitting portion of the light-emitting element of the prototype according to the third embodiment of the present invention is provided. In the case of No. 14 (LED), about 80% of the light-collecting characteristics were obtained within a radiation angle of 45 degrees.
The light collection characteristics were of the order.

Further, when a vibration test was performed on each of the prototype of the light emitting device according to the third embodiment of the present invention and the light emitting device of the conventional prototype, the prototype according to the present invention failed. However, the prototype according to the conventional example had a 5% failure such as disconnection. Next, a fourth embodiment of the light emitting device according to the present invention will be described. In the fourth embodiment, at least one electrode has a part or all of an outer shape (or a side surface) instead of a lead type electrode structure as in the related art. It is intended to realize the implementation. That is, on the opposite side of the portion that holds the light emitting portion in the portion that performs the electrical connection, at least one electrode is electrically connected to the side surface of the light emitting element, and the remaining electrode is on the inside insulated from the electrode on the side surface It has an electrode structure. Usually, when light is emitted by electrical connection, at least two or more electrodes are required. In this case, for example, even when one lamp is individually controlled, at least one pole is set as the outer periphery of the light emitting element, so that different light emitting elements are mounted (contacted, for example, soldered) while maintaining the electrical connection from the outer periphery. Do)
Individual adjustment can be performed by ON / OFF control of the remaining electrodes.

On the surface of the outer peripheral portion having the function of the electrode 11,
By melting and attaching the solder by heating or the like, solidifying it by cooling, and plating it with a conductive material, it is possible to mount it all at once by heating after positioning at the time of mounting. This makes it possible to greatly simplify the manufacturing process (corresponding to claim 5). FIG.
FIG. 6 is an external perspective view showing a configuration of a light emitting device according to the fourth embodiment. FIG. 6 is a cross-sectional view taken along line aa of FIG. 5, and FIG. It is sectional drawing cut | disconnected and shown along the bb line of 5 of FIG. In FIGS. 5 to 7, illustration of a mold body 18 and the like made of a transparent epoxy resin as a translucent material is omitted for the sake of explanation. Of course, molding can also be used in the fourth embodiment. In FIGS. 5 to 7, the electrode 11 has insulation with the electrode 12 with the insulating material 13 interposed therebetween. The connection to the outer periphery of the electrode 12 is made from the side, and the connection to the outside of the electrode 11 is made to protrude from below.

As is apparent from the cross-sectional views of FIGS. 6 and 7, the electrodes 11 and 12 maintain the insulating property via the insulating material 13, and the electrode 11 passes through the inside of the electrode 12. External connection. Even in the case of the embodiments shown in FIGS. 5 to 7, the light emitting unit 1 is attached to the holding units 11a and 12a.
4 can be mounted face-down, thereby simplifying the mounting process. In addition,
In the present invention, there is no limitation on the divided shape of the electrode. For example, an electrode using the side surface may completely cover the side surface, and may have a structure in which a counter electrode keeps the insulating property through an insulating material. The present invention also relates to the thickness of the metal part,
There is no particular restriction. By increasing the thickness of the electrode, the heat capacity of the electrode increases, and the cooling function of the light emitting unit can be improved. FIG. 8 shows a pattern when nine light-emitting elements 14n according to the fourth embodiment are mounted. In the prototype according to the fourth embodiment, the outer circumference is 1 mm.
The pole and the other pole are created with an insulating material sandwiched between the outer poles. At the time of mounting, a through-hole TH for one pole is created on the board, and for the connection using the outer circumference, the outer circumferences are soldered separately. It was realized by doing.

Here, 3 based on the fourth embodiment will be described.
FIG. 12 shows a case where 9 prototype LEDs in mmφ are mounted.
Compared with the case where nine conventional 3 mmφ lamp-type LEDs are mounted as shown in FIG.
The mounting part of the prototype based on the embodiment is 4.5 × 4.
In contrast to 5 mm, in the conventional example, the size was increased to 9 × 9 mm. In connection with the electrodes, in the fourth embodiment, it is only necessary to prepare a single-pole wiring for the LED, and the wiring work is easy because the number of wirings is small even when wiring is performed individually. Next, a fifth embodiment of the present invention will be described. The present invention does not limit the structure constituting the light emitting layer. In the case where the mechanism (light emitting portion) related to light emission is formed on a semiconductor or conductor having conductivity, a small light emitting element can be obtained by the mounting method applied to the present invention. In a light-emitting mechanism (light-emitting portion) in which a hole injection layer and an electron injection layer are stacked on a conductive substrate, the surface of the conductive substrate opposite to the surface on which light emission is stacked is covered with an insulating material. Or mounted on an electrode mechanism (electrical connection means having a holding portion for holding the light emitting layer) via an insulating material.

The connection with the electrode can be made by wire bonding by providing a portion for electrical connection on the surface on which the mechanism (light emitting portion) relating to light emission is laminated. Further, in place of the above, the surface in contact with one electrode is used for directly connecting the substrate surface of the light emitting mechanism (light emitting portion) having conductivity, and the surface in contact with the other electrode is covered with an insulating material. Or mounting with an insulating material in between. On the layer relating to the light emitting layer, it can be connected to the other electrode by wire bonding. In a light emitting unit using a substrate such as sapphire having no conductivity, a substrate having no conductivity is connected to an electrode holding mechanism (holding unit), and connection by wire bonding is performed on the light emitting unit. By doing so, it can be implemented. Further, as a mechanism (light emitting portion) that emits light by injecting a current, there is an LED, an organic EL, or the like. The light-emitting mechanism (light-emitting unit) for injecting a current into these elements does not require a high voltage, and therefore has an advantage that the driving circuit does not require a high voltage and can be driven relatively easily. Corresponding to item 7).

Next, a sixth embodiment of the present invention will be described. In the sixth embodiment, the light emitting device obtained in the third embodiment is mounted on a substrate to obtain a planar illumination device. That is, a planar light source is realized by arranging the light emitting elements obtained in the third embodiment two-dimensionally. Of course, the three primary colors of light {R (red), G (green), and B (blue)} that are already developed are of course possible, but in the present invention, it is particularly necessary because high density mounting is possible. By summarizing the intensity ratio and the number of LEDs for obtaining a desired color, any color can be obtained with better visibility than the conventional technology. In the sixth embodiment, specifically, a light-emitting element having the shape shown in FIG. 5 is manufactured using an LED, mounted on a substrate, and combined with R, G, and B to sequentially form red and blue. A lighting device which produces yellow was manufactured. Each of the colors R and B emits red and blue respectively, and R and G emit light at the same time, whereby yellow is emitted. Also, R, G, B
A total of 36 pieces each of 12 pieces can be used to manufacture a planar lighting device.

A spread illuminating device made by using a 3 mm light emitting element of a prototype according to the present invention and a conventional 3 mm diameter LE
D was used to fabricate a planar lighting device capable of producing the same color, and the characteristics were compared. As a result of this comparison, the color development itself was obtained in the same manner for both the planar lighting device of the present invention and the conventional planar lighting device. However, in terms of mounting area, in the case of the present invention, it was 9 × 9 mm. In the case of the conventional example, since there are two electrodes with a diameter of 3 mm, the pitch of one light emitting element is 3.5 mm on mounting, and the final mounting area is 21 × 2.
1 mm. In the case of the conventional planar lighting device, wiring is always more complicated than the mounting area, and it is necessary to create a wiring pattern as a common electrode on at least a substrate. On the other hand, in the case of the planar lighting device according to the present invention, it has been found that a small and low-cost lighting device can be manufactured (corresponding to claim 8).

Next, a seventh embodiment of the present invention will be described. In the seventh embodiment, a direct-view display device is realized using the light emitting device according to the present invention. The direct-view display device according to the seventh embodiment is configured by two-dimensionally arranging the light-emitting elements of R, G, and B, which are the three primary colors of light, as one unit. R, G,
By controlling B on and off according to the image information,
A high-definition direct-view display device could be created. As the light emitting element used in the direct-view display device according to the seventh embodiment, the light emitting element as shown in FIG. 5 obtained in the fourth embodiment is appropriate. When this light emitting element is used, it is laid out and mounted as shown in FIG. FIG. 9 is a plan view seen from above the light emitting surface of the LED, and uses a light emitting element according to the present invention having a blue light emitting element 19, a green light emitting element 20, and a red light emitting element 21. These blue light emitting element 19, green light emitting element 20,
The red light emitting elements 21 can be combined in an appropriate number according to the size, resolution, etc. of the display device, and the corresponding blue light emitting elements 19, green light emitting elements 20,
A display device that individually controls on and off of the red light emitting elements 21 can be manufactured.

Here, when the characteristics of the direct-view display device obtained in the seventh embodiment and the characteristics of the conventional direct-view display device are compared, the substrate of the conventional direct-view display device is the same as that of the present invention. As in the case of the seventh embodiment, a common electrode pattern was not formed. By wiring 300 common electrodes and 300 individual electrodes on the manufactured substrate, a conventional direct-view display device was manufactured. The time required for this was much longer than the time required for making the direct-view display device of the present invention. Further, a common electrode pattern was formed on a substrate applied to a conventional direct-view display device. In this case, the cost for manufacturing the conventional display device has greatly increased the cost for manufacturing the substrate applied to the direct-view display device of the present invention. Further, regarding the display quality, when the direct-view display device of the present invention is compared with the conventional direct-view display device, the display by the direct-view display device of the present invention shows that the dots are fine, so that the conventional direct-view display device Higher definition than the device could be realized. In addition, the production cost of the direct-view display device of the present invention was lower (corresponding to claim 9).

Next, an eighth embodiment of the present invention will be described. In the eighth embodiment, a projection display device is configured by using the planar illumination device obtained in the sixth embodiment as a light source. By using an LED as a light-emitting unit of the projection display device, a thin planar light-emitting body (that is, the planar illumination device obtained in the sixth embodiment) is realized, and this is used as a projection-type display device. This is realized as a display device. In the projection display device of the present invention,
Since high definition can be realized, a small light source can be manufactured, and the entire device can be reduced in size. FIG. 10 is a configuration explanatory diagram showing the configuration of the optical system of the projection display device according to the eighth embodiment. In the case of FIG. 10, three-color primary surface illumination devices of R, G, and B are individually created. That is, in FIG. 10, the red planar lighting device 22, the green planar lighting device 23,
Red, green, and blue planar lights are emitted from the blue planar illumination device 24, respectively. The red planar illuminator 22 and the blue planar illuminator 24 are disposed so as to face each other, and the green planar illuminator 23 is perpendicular to the red planar illuminator 22 and the blue planar illuminator 24. Is arranged.

In order to align the polarization of each of the red, green, and blue emitted light, a polarization conversion is performed in front of the red planar illuminator 22, the green planar illuminator 23, and the blue planar illuminator 24, respectively. Polarization conversion means (for example, a polarization filter or the like) 25 to 27 for performing the operation are arranged. Further, light valves 28 to 30 (hereinafter, referred to as “LV”) are arranged in front of these polarization conversion units 25 to 27, respectively. Polarization conversion means 25-27 and LV28-30
Constitutes a part of the optical system. In the embodiment shown in FIG. 10, LVs 28 to 30 are, for example, transmission type LVs.
Is used. The red, green, and blue light emitted from each of the red planar lighting device 22, the green planar lighting device 23, and the blue planar lighting device 24
The light is respectively polarized by ２７ to 27 and is incident on LVs 28 to 30, and is modulated by the LVs 28 to 30. LV28-30
A dichroic prism 31 is arranged in front of the. The red, green, and blue emission lights modulated by the LVs 28 to 30 enter the dichroic prism 31,
The light is synthesized by the dichroic prism 31.

A projection lens 32 is disposed in front of the dichroic prism 31, that is, in the right side of FIG. The projection lens 32 is a dichroic prism 31
This is a lens for projecting a red, green, and blue combined color light synthesized by the above on a screen (not shown). The projection-type display device according to the eighth embodiment having the above-described configuration can realize a reduction in the size of the entire device. The characteristics of the projection type display device shown in FIG. 10 and a conventional projection type display device will be compared. For this comparison, in the projection display device according to the present invention, a light source was prepared using an LED having a diameter of 3 mm, and this was mounted in a layout as shown in FIG. The projection type display device according to the present invention has about 20% higher brightness than the conventional projection type display device. On the other hand, in the conventional projection display device, since the light source is larger than the projection display device according to the present invention, if the device dimensions are equal,
Since the irradiation light irradiates other than the LV, a decrease in the illuminance on the LV was observed (corresponding to claim 10).

In the conventional projection display device, in order to obtain the same illuminance as the projection display device according to the present invention, it is necessary to reduce the light from the light source. Therefore, the cost of the optical components increases. Further, in order to realize the same manufacturing cost of the conventional projection display device and the projection display device according to the present invention, the light source position in the conventional projection display device is determined by the light source position in the projection display device according to the invention. The projection type display device of the related art is larger in size as a whole. As described above, according to the eighth embodiment, with the same outer shape at the same manufacturing cost, the illuminance can be increased by the eighth embodiment, and when the illuminance and the manufacturing cost are equal, the device can be downsized. I understood. FIG. 11 is a diagram illustrating the configuration of a projection display device obtained in the ninth embodiment according to the present invention. In FIG. 11, a reflection type LV {for example, a digital mirror device (DM)
D), an example using ferroelectric liquid crystal or the like is shown.

In FIG. 11, the ferroelectric liquid crystal LV33
And the spread illuminating devices 34 shown in FIG. 9 are arranged so as to have a positional relationship in a direction perpendicular to each other. The spread illuminating device 34 is capable of lighting R, G, and B, respectively. In front of the spread illuminating device 34, the R, G, and B light emitted from the spread illuminating device 34 is polarized. Polarizing means 3
5 are arranged. The polarizing means 35 and the LV 33 constitute an optical system for performing polarization conversion and irradiating light onto the LV. A polarizing beam splitter 36 is arranged in common in front of the polarizing means 35 and the LV 33. Polarizing beam splitter 36
The projection lens 37 is disposed in front of (right side in FIG. 11). With this configuration, the R, G, and B light emitting elements of the planar illumination device 34 are switched and driven, and the R, G, and B emitted light emitted from the planar illumination device 34 are polarized by the polarization unit 35. After aligning the polarized light, the display data corresponding to each of the R, G, and B emitted lights can be time-divisionally applied to the LV 33 to perform field sequential driving.

In the ninth embodiment, the display device can be further reduced in size by reducing the size of the light source. FIG. 1 shows a ninth embodiment in which an LED is used as a light-emitting unit, the planar illumination device obtained in the fifth embodiment is used, and a ferroelectric liquid crystal (reflection type) is used as an LV.
Thus, a projection-type illumination device (projector) as shown in FIG. This projection type illuminator has a ferroelectric liquid crystal LV33,
The planar illumination device 34 obtained in the above-described embodiment, as described above, the polarization unit 35 and the polarization beam splitter 3 that constitute an optical system for performing polarization conversion and irradiating light onto the LV.
6. It is composed of a projection lens 37. R, G, and B of the LEDs of the light emitting unit are sequentially turned on in a time-division manner, and field sequential driving for displaying display data corresponding to each of R, G, and B on the LV 33 is performed. Thus, a small-sized and low-cost projection illuminating device can be obtained also in the ninth embodiment.

[0037]

As described above, according to the present invention, at least a light-emitting portion that emits light by supplying a voltage or a current has a function as an electrode for making an electrical connection to the light-emitting portion, and is used alone. Since the structure includes the electric connection means having a function of holding the light emitting portion, a very small light emitting element can be provided. According to the invention of claim 2 of the present invention, the electrical connection means including the required number of electrodes of the light-emitting portion is made of a conductive material having at least mutual insulation, and integrated.
A very small light-emitting element can be provided. According to the light emitting element of the third aspect of the present invention, the holding portion for holding the light emitting portion is provided with a reflection function of reflecting the light emitted from the light emitting portion. Can increase the efficiency of use.

According to the light emitting element of the fourth aspect of the present invention, since the side of the holding section on which the light emitting section is provided is covered with a translucent material, the utilization efficiency of light emitted from the light emitting section is improved. Can be increased. According to the invention of claim 5 of the present invention, at least one electrode is electrically connected to the light emitting unit on the opposite side of the part holding the light emitting unit, among the electric connection parts, and is made of a conductive material. And the remaining electrodes are electrically connected to the inside conductive material that is electrically insulated from the conductive material on the side surface. In addition, it is possible to provide a light emitting element that can be easily and inexpensively connected to a driving circuit.

According to the invention of claim 6 of the present invention, a light emitting layer having a function of emitting light by injecting a current is stacked on a conductive substrate, and at least one light emitting layer is provided on the stacked light emitting layer. A portion for performing the above electrical connection means is provided, and has an electrical connection means for connecting to one electrode via a conductive material or for connecting to the electrode using wire bonding on the conductive material and the light emitting layer. In addition, since the surface in contact with the holding unit is provided with means for insulating at least different electrodes, a light emitting unit that can be miniaturized can be realized even in a light emitting unit formed by current injection on a conductive substrate. An element can be provided.

According to the invention of claim 7 of the present invention, the light emitting section has a light emitting layer which emits light by injecting a current into at least an insulating material, and at least one light emitting layer is provided on the light emitting layer. Since the electric connection means is provided and the electric connection means and the light emitting section are connected by wire bonding, downsizing can be realized even with the light emitting section by current injection formed on the insulating substrate. A light-emitting element can be provided. According to the invention of claim 8 of the present invention, at least one of the light emitting portion that emits light by supplying a voltage or a current and the portion that electrically connects the light emitting portion opposite to the portion that holds the light emitting portion is at least one. One of the electrodes is electrically connected to the light emitting portion and the other is electrically connected to a side surface made of a conductive material, and the other electrode is a conductive material on the inside that is electrically insulated from the conductive material on the side surface. And a light-emitting element including an electric connection means electrically connected to the light-emitting element, and particularly, a high-definition planar illumination device can be provided.

According to the ninth aspect of the present invention, by supplying at least a voltage or a current, three colors of light emitting diodes emitting red, green, and blue light, respectively, are used.
A light-emitting portion formed by a light-emitting diode arranged two-dimensionally with a pixel as a unit, and at least one of the electrodes for electrical connection is opposite to a portion holding the light-emitting portion. While being electrically connected to the light emitting portion, it is electrically connected to the side surface made of a conductive material, and the remaining electrodes are electrically connected to the inside conductive material which is electrically insulated from the conductive material on the side surface. Electrical connection means to be connected, and means for individually turning on and off each of the light emitting diodes, and comprising an on / off controlled light emitting diode to display an image by blinking,
A direct-view display device with high definition, low mounting cost, and easy manufacture can be provided. According to the invention of claim 10 of the present invention, by supplying at least a voltage or a current, a light-emitting portion composed of a light-emitting diode in which light-emitting layers that emit red, green, and blue light are respectively stacked, and a portion that performs electrical connection On the other side of the portion holding the light emitting portion, at least one electrode is electrically connected to the light emitting portion, and is electrically connected to a side surface made of a conductive material, and the remaining electrodes are formed on the side surface. A light source provided by a planar lighting device having a light emitting element mounted on a substrate, the light emitting element having an electrically connecting means electrically connected to a conductive material inside which is electrically insulated from the conductive material; And an optical system for condensing the light generated from the light and projecting the light to a predetermined portion. Therefore, it is possible to provide a small-sized, low-cost, and bright projection display device.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an external configuration of a light emitting device according to a first embodiment of the present invention.

FIG. 2 is a sectional view showing a configuration of a light emitting device according to a first embodiment of the present invention.

FIG. 3 is a perspective view showing an external configuration of a light emitting device according to a second embodiment of the present invention.

FIG. 4 is a perspective view showing a configuration of a third embodiment of the light emitting device according to the present invention.

FIG. 5 is a perspective view illustrating a configuration of a light emitting device according to a fourth embodiment of the present invention.

FIG. 6 is a sectional view taken along line aa of FIG. 5;

FIG. 7 is a sectional view taken along line bb of FIG. 5;

FIG. 8 is a perspective view showing a state in which an LED is mounted on a substrate in a fourth embodiment of the light emitting device according to the present invention.

FIG. 9 is a plan view of a light emitting element according to a fourth embodiment of the present invention, as viewed from the light emitting surface of the LED when the LEDs are arranged in a plane and applied to a direct-view display device.

FIG. 10 shows an LE of a light emitting section in a light emitting device according to the present invention.
FIG. 2 is a configuration explanatory diagram showing a configuration of a projection type display device using R, G, and B of D as individual light sources.

FIG. 11 is a configuration explanatory view showing a configuration of a projection type display device using a planar lighting device composed of light emitting elements according to the present invention and using a ferroelectric liquid crystal for a light valve.

FIG. 12 is a cross-sectional view illustrating a configuration of a conventional light emitting element.

[Explanation of symbols]

 11, 12 Electrode 11a, 12a Holding portion 13, 15 Insulating material 14 Light emitting portion 14n LED 16, 17 Wire bonding 18 Molded body 19 Blue light emitting device 20 Green light emitting device 21 Red light emitting device 22 Red planar lighting device 23 Green planar illumination Device 24 Blue planar illumination device 25 to 27, 35 Polarization conversion means 28 to 30, 33 LV (light valve) 31 Dichroic prism 32 Projection lens 34 Planar illumination device 36 Polarization beam splitter 37 Projection lens

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kazuya Miyagaki 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Co., Ltd. (72) Inventor Ikuo Kato 1-3-6 Nakamagome, Ota-ku, Tokyo Ricoh Co., Ltd. (72) Inventor Yasuyuki Takiguchi 1-3-6 Nakamagome, Ota-ku, Tokyo F-term in Ricoh Co., Ltd. 5C094 AA15 BA25 CA19 CA24 5F041 AA24 AA47 DA01 DA07 DA39 FF01 FF11

Claims (10)

[Claims] 1. A light emitting unit that emits light by supplying at least a voltage or a current, and an electrical connection having a function as an electrode for electrically connecting the light emitting unit and a function of holding the light emitting unit alone. And a light emitting element. 2. The light-emitting device according to claim 1, wherein the electric connection means comprising the required number of electrodes of the light-emitting portion is made of a conductive material having at least mutual insulation and integrated. . 3. The light-emitting device according to claim 1, wherein the holding unit that holds the light-emitting unit has a reflection function of reflecting light emitted from the light-emitting unit. 4. The light emitting device according to claim 3, wherein a side of the holding section on which the light emitting section is provided is covered with a translucent material. 5. A portion of the portion for making an electrical connection, which is opposite to a portion for holding the light emitting portion, has at least one electrode electrically connected to the light emitting portion and electrically connected to a side surface made of a conductive material. The light emitting device according to claim 4, wherein the light emitting element is electrically connected to an inner conductive material which is electrically connected to the inner surface of the side surface and electrically insulated from the conductive material. 6. A portion in which a light emitting layer having a function of emitting light by injecting an electric current is stacked on a conductive substrate, and at least one or more electrical connection means are provided on the stacked light emitting layer. And an electrical connection means for connecting to one of the electrodes via a conductive material, or for connecting the conductive material and the electrode using wire bonding on the light emitting layer, and having at least a different surface for contacting the holding portion. The light emitting device according to any one of claims 1 to 5, further comprising means for insulating the electrodes. 7. The light emitting section has a light emitting layer that emits light by injecting a current into at least an insulating material,
7. The method according to claim 1, wherein at least one or more electrical connection means are provided on the light emitting layer, and the electrical connection means and the light emitting unit are connected by wire bonding.
The light-emitting device according to any one of the above items. 8. A light-emitting portion that emits light by supplying at least a voltage or a current, and at least one electrode of a portion that performs electrical connection opposite to a portion that holds the light-emitting portion has at least one electrode connected to the light-emitting portion. It is electrically connected and electrically connected to the side surface made of a conductive material, and the remaining electrodes are electrically connected to the inside conductive material which is electrically insulated from the conductive material on the side surface. A spread illuminating device comprising: a light emitting element having electrical connection means mounted on a substrate. 9. A light-emitting diode in which one pixel is constituted by light-emitting diodes of three colors that emit red, green, and blue light by supplying at least a voltage or a current, respectively, and the two-dimensionally arranged light-emitting diodes are used as a unit. At least one electrode is electrically connected to the light emitting unit, and is electrically connected to a side surface made of a conductive material. The remaining electrodes are electrically connected to the conductive material on the inside, which is electrically insulated from the conductive material on the side surface, and each of the light emitting diodes is individually turned on. A display device comprising: an off-control means; and displaying an image by blinking of a light-emitting diode controlled to be on and off. 10. A light-emitting portion including a light-emitting diode in which light-emitting layers that emit red, green, and blue light are stacked by supplying at least a voltage or a current, respectively, On the opposite side of the holding part, at least one electrode is electrically connected to the light emitting portion and electrically connected to a side surface made of a conductive material, and the remaining electrodes are electrically connected to the conductive material on the side surface. A light source provided by a planar lighting device having a light emitting element mounted on a substrate and having a light emitting element having an electrically connecting means electrically connected to a conductive material on the inside that is electrically insulated, and condensing light generated from the light source And an optical system for projecting light to a predetermined portion.