JP2008084967A - Light-emitting device, lighting system, electrooptical device, and electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light-emitting element that reduces costs and is miniaturized, prevents irregularities in luminance, and can obtain sufficient light emitting luminance even in monochrome display, and to provide a lighting system, an electrooptical device, and electronic equipment. <P>SOLUTION: A light-emitting device 1, where a plurality of light-emitting elements having different emission spectra are arranged in a package 2, has a light-emitting element circuit, having a first LED 3 for emitting blue light, and a second LED 4 that is connected to the first LED 3 inversely in parallel and emits red light having a color differing from that of the first LED 3. The light-emitting device 1 has a current supply means capable of switching a direction for allowing current to flow in an opposite direction to the light-emitting element circuit. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a light emitting device, a lighting device, an electro-optical device, and an electronic apparatus.

  Currently, liquid crystal display devices are widely used in home televisions, PC monitors, and other various electronic devices. As such a liquid crystal display device, there is known a liquid crystal display device having a structure in which light from a point light source or a linear light source is converted into planar light and irradiated onto a liquid crystal panel for display. An LED (Light Emitting Diode) is often used as the point light source, and a cold cathode tube is often used as the linear light source. Recently, it has been proposed that such a liquid crystal display device is mounted on a vehicle and used for meter display, warning display, display of information from a car navigation system, and the like.

  In a liquid crystal display device provided in a vehicle monitor system, an important warning display for a user is displayed in red. Conventionally, a desired luminescent color is usually constituted by three LEDs having luminescent colors corresponding to R, G, and B, respectively. However, when performing monochromatic display using only red, such as a warning display, there is a problem in that the emission luminance is greatly reduced compared to the case of performing white display because the other two colors can suppress light emission. Since the warning display is very important information for the user, it is a problem to realize a sufficient display luminance that the user does not overlook.

As a liquid crystal display device that solves such problems, for example, the backlight unit has a white LED and a red LED, and when a warning display is required, both the white LED and the red LED are turned on. There has been proposed a display device that secures display brightness and performs control so that only a white LED is turned on when information to be displayed is not a warning, and displays a warning in red in a display area of the LCD.
JP 2004-70193 A

  The backlight unit of the above document is configured by arranging a plurality of LEDs on both sides of a light guide plate, and alternately arranging white LEDs and red LEDs. However, with such an LED arrangement, there is a risk that brightness unevenness will occur in the light exit surface and the appearance will deteriorate, and it is difficult to reduce the size of the entire apparatus due to an increase in mounting space.

  The present invention has been made in view of the above-mentioned problems, and its object is to achieve optical properties capable of obtaining sufficient color rendering even in monochromatic display while preventing color unevenness while achieving cost reduction and downsizing. A light emitting element, a lighting device, an electro-optical device, and an electronic device which are excellent in the above are provided.

  In order to solve the above problems, a light-emitting device of the present invention is a light-emitting device in which a plurality of light-emitting elements having different emission spectra are arranged in a package, and a first light-emitting element that emits predetermined monochromatic light; A light-emitting element circuit including a second light-emitting element that is connected in parallel in the opposite direction to the first light-emitting element and emits monochromatic light having a color different from that of the first light-emitting element. The circuit is provided with a current supply means capable of switching the direction of current flow in the reverse direction.

  According to such a configuration, the emission color can be changed by switching the direction of current flow to the opposite direction. Further, the configuration is different from the conventional case where the emission color is obtained by color mixing, and since each of them emits light independently, the color rendering is good and the occurrence of uneven color can be suppressed. As a result, a light emitting device with high luminous efficiency can be obtained.

Further, the anode terminal of the first light emitting element and the cathode terminal of the second light emitting element are commonly connected to a pair of input / output terminals, and the cathode terminal of the first light emitting element and the anode of the second light emitting element. It is preferable that the terminal is shared and connected to the pair of output terminals.
According to such a configuration, either the first light-emitting element or the second light-emitting element can be selectively driven by selecting a terminal through which a current flows.

It is also preferable that the first light emitting element emits blue light and the second light emitting element emits red light.
According to such a configuration, a desired emission color can be easily obtained by selecting a light emitting element to be driven. In addition, since there are many materials that convert blue in the types of phosphors, white can be easily created by using a light emitting element that emits blue light. Furthermore, since a bright red color can be obtained by using a light emitting element that emits red light, it is suitable for warning display such as an in-vehicle display.

In addition, it is preferable that the first light-emitting element and the second light-emitting element have a protective function of preventing currents in opposite directions from being supplied to the other light-emitting elements.
According to such a configuration, it is possible to prevent an internal circuit from being damaged due to a reverse current flowing from static electricity or the like. By providing such a protection function, product performance can be maintained for a long time.

It is also preferable that the plurality of first light emitting elements are connected in series and the plurality of second light emitting elements are connected in series.
According to such a configuration, since a plurality of first light emitting elements and a plurality of second light emitting elements are provided, the light emission luminance of the light emission color by each light emitting element can be improved and luminance unevenness can be prevented. .

It is also preferable that the light emitting surface of the first light emitting element is covered with a phosphor.
According to such a configuration, the phosphor is excited based on, for example, blue light irradiation to generate yellow light (green light), and this yellow light (green light) is the blue light described above. When mixed with the above, white light is generated due to the complementary color relationship. Therefore, the emission color of the first light-emitting element can be white.

It is also preferable that the phosphor is formed only on the light emitting surface of the first light emitting element and not formed on the second light emitting element.
According to such a configuration, since the phosphor is not formed in the second light emitting element, vivid red light can be obtained without being discolored by the phosphor.

It is also preferable that the first light-emitting element and the second light-emitting element are sealed with a resin containing a phosphor.
According to such a configuration, the phosphor can be provided on the first light emitting element simply by filling the resin containing the phosphor into the recess of the package, as in the conventional case. Manufacture is facilitated as compared with the case of coating on the light emitting surface of the light emitting element.

An illuminating device of the present invention includes the above light emitting device and a light guide plate that converts light emitted from the light emitting device into planar light.
According to the illumination device of the present invention, it is possible to obtain irradiation light with high luminance. In particular, the luminance and saturation of the light emission color of the second light emitting element are improved, and the display luminance due to red monochromatic light can be ensured. Further, since a light emitting device having a plurality of light emitting elements having different emission spectra is provided in the package, a plurality of colors can be reproduced in one package. Therefore, since it is not necessary to provide a plurality of packages for each color, the overall configuration of the apparatus is simplified and the size can be reduced. Thereby, the cost can be reduced and the yield is improved.

An electro-optical device of the present invention includes the above-described illumination device and a light modulation device that modulates light from the illumination device.
According to the electro-optical device of the present invention, there is no luminance unevenness and color unevenness, and an image can be displayed with high quality.

An electronic apparatus according to the present invention includes the electro-optical device as described above.
According to the electronic device of the present invention, it can have a high-luminance illumination function. Therefore, the user can be surely recognized without missing the warning display.

  Embodiments of the present invention will be described below with reference to the drawings. In the following drawings, the film thicknesses and dimensional ratios of the respective components are appropriately changed in order to make the drawings easy to see.

[Light emitting device]
FIG. 1 is a plan view showing a schematic configuration of the light emitting device in the present embodiment. FIG. 2 is a side sectional view showing a schematic configuration of the light emitting device. FIG. 3 is an internal circuit diagram of the light emitting device.
As shown in FIG. 1, the light emitting device 1 of the present embodiment has a plurality of light emitting elements having different emission spectra, and these light emitting elements are mounted in a recess 2 a of a package 2. In the present embodiment, a first LED 3 (first light emitting element) that emits blue monochromatic light and a second LED 4 (second light emitting element) that emits red monochromatic light are provided.

  The first LED 3 is formed of a Zener diode that emits blue light (wavelength is, for example, 430 to 470 nm) such as InGaN or GaN.

  The second LED 4 is composed of a Zener diode that emits red light (wavelength is, for example, 580 to 780 nm) such as GaP-based or GaAlAs mixed crystal.

  As shown in FIG. 2, the light emitting surface 3a (irradiation area) of the first LED 3 is coated with a phosphor 5 that receives blue light and emits fluorescence of other colors. The phosphor 5 can be configured using, for example, a YAG-based phosphor (YAG: Ce phosphor) that emits yellow light when excited by blue light. A material that emits complementary color light for blue light is used as the material.

  The phosphor 5 is formed on the light emitting surface 3a of the first LED 3 with a uniform thickness. By making the thickness of the phosphor 5 uniform, it is possible to obtain a light emission color with little variation in chromaticity (color unevenness) in the light emission observation direction.

  As shown in FIG. 3, the first LED 3 and the second LED 4 are connected in parallel in opposite directions to constitute a light emitting element circuit 6. Then, the anode terminal of the first LED 3 and the cathode terminal of the second LED 4 are shared and connected to the first current supply unit 7 composed of a pair of terminals, and the cathode terminal of the first LED 3 and the anode terminal of the second LED 4 are shared. Are connected to a second current supply unit 8 composed of a pair of terminals.

  The first current supply unit 7 and the second current supply unit 8 are current supply means that can switch the direction of current flow to the light emitting element circuit 6 in the reverse direction, and one of a pair of terminals that each has. Is for the blue signal and the other is for the red signal. This current supply means fulfills the function of changing the direction of current flow so that a forward current flows to the first LED 3 or the second LED 4, and can thereby select the LED to emit light.

  Specifically, the first current supply unit 7 includes a green signal input terminal A1 and a red signal output terminal C2, and the second current supply unit 8 includes a green signal output terminal C1 and a red signal input terminal A2. The first current supply unit 7 and the second current supply unit 8 are drawn from both sides of the package 2.

  Since each of the LEDs 3 and 4 is formed of a Zener diode, the LED 3 and 4 have a protection function for preventing currents flowing in opposite directions from each other. In this way, for example, even if static electricity flowing through the terminal flows to the LED side different from the LED side to be emitted, a reverse current is prevented from flowing to the LED, so that the light emitting element circuit 6 can be protected.

  The first LED 3 and the second LED 4 are mounted on a heat sink (not shown) made of a material having good thermal conductivity such as aluminum or copper. At this time, it arrange | positions so that the direction of 1st LED3 which discharge | releases white light may become higher heat dissipation than 2nd LED4. For example, the heat dissipation of the first LED 3 is enhanced by arranging the first LED 3 in the center of the heat sink and arranging the second LED 4 toward the corner. Alternatively, only the first LED 3 may be mounted on the heat sink.

  Since the driving time of the first LED 3 is longer than that of the second LED 4 in an electronic device to be described later, the amount of heat generated is inevitably larger than that of the second LED 4. Therefore, it is important to increase the heat dissipation of the first LED 3 in order to extend the life.

  In the above embodiment, the phosphor 5 is formed directly on the light emitting surface 3a of the first LED 3. However, as shown in FIG. 4, the silicon resin 9 mixed with the phosphor 5 is used as the recess 2a of the package 2. The first LED 3 and the second LED 4 may be sealed inside. Further, as shown in FIGS. 5A and 5B, a cap 10 made of silicon rubber including the phosphor 5 may be attached so as to cover the light emitting surface 1 a of the light emitting device 1. However, in order to avoid the discoloration of red light from the second LED 4, it is preferable to provide the phosphor 5 only in the first LED 3. As a result, it is possible to obtain emitted light suitable for monochromatic display without reducing the luminance and saturation of the second LED 4.

  Further, a plurality of LEDs 3 and 4 may be provided. By connecting the plurality of first LEDs 3 in series and connecting the plurality of second LEDs 4 in series, the light emission luminance of each emission color by the LEDs 3 and 4 is improved, and the luminance unevenness of white light or red light is improved. Can be prevented.

[Lighting device]
FIG. 6 is a perspective view illustrating an example of a lighting device according to the present embodiment, and FIG. 7 is a plan view illustrating a schematic configuration of the light emitting unit.
The illuminating device 11 of this embodiment is used as a backlight of a liquid crystal device, for example, and is provided on the outer surface side of the liquid crystal panel. As shown in FIG. 6, a light emitting unit 13 including a plurality of light emitting devices 1, a light guide plate 14 that converts light from the light emitting units 13 into a planar light source, a light diffusion sheet 15, a first prism sheet 16, the 2nd prism sheet 17, the reflective polarizing plate 18, the reflective sheet 19, the heat radiator 20, and the flame | frame 21 which covers these are comprised.

  As shown in FIG. 7, the light emitting unit 13 is configured such that each light emitting surface 1 a faces the same direction so that the light emitted from each light emitting device 1 is not blocked by the other light emitting devices 1. At this time, the first current supply unit 7 of the light emitting device 1e and the first current supply unit 7 of the light emitting device 1f are connected by connecting the corresponding green signal input terminals A1 and red signal input terminals A2. Moreover, the 2nd current supply part 8 of the light-emitting device 1f and the 2nd current supply part 8 of the light-emitting device 1g are connected by connection of corresponding green signal output terminal C1 and red signal input terminal A2.

  Then, the green signal input terminal A1 and the red signal output terminal C2 (second current supply unit 8) of the light emitting device 1e pulled out from the light emitting unit main body 13a, and the green signal output terminal C1 and the red signal input terminal A2 (second output) of the light emitting device 1g. 1 current supply section 7) is electrically connected to the external electrodes. A current is supplied to each first LED 3 or each second LED 4 based on the electric power supplied from the outside to the external electrode.

  As shown in FIG. 6, the light guide plate 14 is made of a light-transmitting material such as acrylic resin or polycarbonate resin, is configured in a plate shape having a rectangular shape in plan view, and propagates from a light incident surface 14 a configured by one end surface. Light enters in the direction F and propagates in the same direction. The internally propagating light is gradually polarized in the light emitting direction (on the light emitting surface 14b side) and emitted from the light emitting surface 14b. Examples of means for polarizing the internally propagating light traveling in the propagation direction F in the light emitting direction include a concavo-convex structure or a printed layer formed on the back surface on the opposite side of the light emitting surface 14b.

  A reflection sheet 19 made of a white polyethylene sheet or the like is disposed behind the light guide plate 14 so that light leaked from the back surface is emitted from the light exit surface 14b. The reflection sheet 19 is preferably provided so as to face the end surface of the light guide plate 14.

  Such a light guide plate 14 and the light emitting unit 13 are supported by a heat radiator 20 having good thermal conductivity such as aluminum. The heat radiating body 20 is configured in a case shape that covers the back and side surfaces of the light emitting unit 13 and the light guide plate 14 and has an opening that exposes at least the light emitting surface 14b, and accommodates the light emitting unit 13 and the light guide plate 14. It is preferable to be configured. The light emitting unit 13 is mounted in the radiator 20 so that the light emitting surface 1a faces the light incident surface 14a of the light guide plate 14 at the time of assembly. At this time, it is being fixed to the inner surface of the side-plate part 20a of the heat radiator 20 via the adhesive agent with a heat conductive tape, thermal radiation grease, a thermal conductive rubber, etc. The heat dissipation area is increased by the case-like radiator 20 and the heat dissipation efficiency is increased.

  The light diffusion sheet 15 is disposed on the light emitting surface 14b of the light guide plate 14 (liquid crystal panel side). The light diffusion sheet 15 is a plate-shaped sheet member that diffuses light emitted from the light guide plate 14. As the light diffusing sheet 15, an acrylic sheet in which a diffusing agent is dispersed can be used. With this light diffusion sheet 15, the inner surface luminance of the light emitted from the light guide plate 14 can be made uniform, and the grooves of the first prism sheet 16 and the second prism sheet 17 and reflection of uneven shapes (luminance unevenness) can be prevented. It is like that. The exposed area of the light diffusion sheet 15 that is not covered by the first prism sheet 16 does not enter the display area (effective light emission area).

  The first prism sheet 16 is disposed on the upper surface 15 a side of the light diffusion sheet 15. The second prism sheet 17 is disposed on the upper surface 16 a side of the first prism sheet 16. Each of the first prism sheet 16 and the second prism sheet 17 has a prism surface on one surface side (the upper surface side in the drawing) made of a transparent acrylic resin or the like. Formed and configured. And the 1st prism sheet 16 and the 2nd prism sheet 17 are arrange | positioned so that the extending direction of the unevenness | corrugation in each prism surface may become the direction which mutually orthogonally crosses.

The reflective polarizing plate 18 is disposed on the second prism sheet 17 and transmits a first polarization component having a polarization axis oriented in a predetermined direction out of illumination light emitted from the light exit surface 14b of the light guide plate 14. It has a function of reflecting the second polarization component orthogonal to the predetermined orientation. Then, the first polarized component of the illumination light is transmitted and emitted, and the second polarized component is reflected and returned to the light guide plate 14 once. However, the reflected light is returned again by the reflection sheet 19 or the like, and eventually becomes the first polarized component. Things are emitted as illumination light. The light utilization efficiency is improved and the luminance level is increased as compared with the case where an absorption type polarizing plate is provided.
The reflective polarizing plate 18 can be omitted when polarized light is not required as illumination light.

  The reflection sheet 19 is disposed behind the light guide plate 14 and the light emitting unit 13 and is made of a white polyethylene sheet or the like, reflects the light leaked from the back surface of the light guide plate 14 and the light emitting unit 13 and is emitted from the light emitting surface 14b. It is like that. The reflection sheet 19 is configured in a case shape that covers the back and side surfaces of the light guide plate 14 and the light emitting unit 13 and has an opening that exposes at least the light emitting surface 14 b of the light guide plate 14. It is formed to accommodate. In the illustrated example, a plurality of light emitting units 13 are arranged at predetermined intervals along the light incident surface 14 a of the light guide plate 14. The case-like reflection sheet 19 allows the light guide plate 14 and the light emitting unit 13 to be appropriately positioned as necessary.

  Each component described above is covered with a frame 21 made of synthetic resin, stainless steel, or the like from the reflective polarizing plate 18 side. The frame 21 is fixed to the heat radiating body 20 in a state in which the respective constituent members are accommodated. The frame 21 is provided with an opening area 21a that at least optically exposes an illumination area AL set in a predetermined range of the light emitting surface 14b of the light guide plate 14. And each said structural member is accommodated and hold | maintained by the flame | frame 21 and the heat radiator 20 in the up-down direction, and the illuminating device 11 of this embodiment is comprised.

  According to the illuminating device 11 configured as described above, when a current is supplied from the green signal input terminal A1 to the green signal output terminal C1 of the light emitting unit 13 illustrated in FIG. Since the current flows, the first LED 3 is driven. The driven first LED 3 emits blue light. When the blue light emitted from the first LED 3 passes through the phosphor 5, a part of the blue light is wavelength-converted (excited) by the YAG-based phosphor 5 and thus yellow light, that is, green light and red light. It is converted into mixed light with light, and this is mixed with blue light transmitted through the YAG phosphor 5 and emitted to generate white light.

  This white light is a standard xy chromaticity diagram showing the hue area for the Munsell hue established by the CIE (Commission Internationale de l'Eclairage) in FIG. 8 (where x is the wavelength of red light (700 nm)) y belongs to the standard white (WHITE) region in the wavelength of green light (546 nm). Since the white light obtained in this way is generated only by the first LED 3, white light can be effectively obtained with a simpler configuration than in the case of the conventional additive color mixing method.

  On the other hand, when a current is passed from the red signal input terminal A2 to the red signal output terminal C2 of the light emitting unit 13 shown in FIG. 7, the second LED 4 is driven because a forward current (forward current) flows to the second LED 4. . The driven second LED 4 emits red light. Since the second LED 4 is not provided with the phosphor 5, the second LED 4 is vivid red light with good color rendering without the influence (discoloration) of the phosphor 5.

  Since the red light thus obtained is generated only by the second LED 4, the red light can be obtained efficiently. Since it is monochromatic light emission, it becomes a uniform light emission color with no color unevenness.

  The light generated from the first LED 3 and the second LED 4 as described above enters the light guide plate 14. The incident light propagates through the light guide plate 14 and is emitted from the light exit surface 14 b side of the light guide plate 14 by reflection by the reflection sheet 19 or diffusion by the diffusion sheet 15.

  According to the illuminating device 11 of the present embodiment, in the current supply means (the first current supply unit 7 and the second current supply unit 8), the first LED 3 or the second LED 4 is selectively driven by selecting a terminal through which a current flows. Can be made. That is, the emission color can be changed by switching the direction of current flow in the reverse direction. Since the configuration differs from the conventional case where the emission color is obtained by color mixing, white light and red light are emitted separately from each LED 3 and 4, so that irradiation light with good color rendering properties is generated without causing color unevenness. Obtainable. In particular, the brightness and saturation of red are improved, and the visibility of monochromatic display can be improved. As described above, it is possible to efficiently secure emitted light having a sufficient color rendering property even in a single color display with a simple configuration. In addition, the simplification of the configuration can reduce the size and the cost can be expected to improve the yield.

[Electro-optical device]
FIG. 9 is a schematic configuration diagram of the electro-optical device, and is a perspective view in which a part of the illumination device is cut away.
The electro-optical device of the present embodiment is a liquid crystal device 100 including the illumination device 11 having the above-described configuration and a liquid crystal panel 25 (light modulation device) including a color filter. The liquid crystal panel 25 is formed by laminating transparent substrates 26 and 27 made of glass, plastic, or the like with a sealing material, and encapsulating liquid crystals between the opposing substrates 26 and 27. The liquid crystal panel 25 is provided with a polarizing plate 28. Normally, a pair of polarizing plates is provided, but the polarizing plate on the side of the illumination device 11 is omitted because it can be substituted by the reflective polarizing plate 18 provided in the illumination device 11.

  The liquid crystal panel 25 is arranged such that the display area AD overlaps with the opening area 21a (illumination area AL) of the frame 21. One end portion of the wiring board is mounted on the liquid crystal panel 25, and the other end portion 31 of the wiring board 30 is disposed behind the lighting device 11 (on the back surface of the bottom plate portion 20b of the radiator 20). It is mounted on the substrate 33. Although not shown, electrical components (not shown) are mounted on the control circuit board 33, which is not shown. In the present embodiment, the wiring board 30 passes through the outside of the side portions of the frame 21 and the radiator 20 and extends to the back side.

  FIG. 10 is a schematic block diagram showing the configuration of the control system of the liquid crystal device 100. The control system includes a control circuit 33A, a liquid crystal drive circuit 27A controlled by the control circuit 33A, and an illumination device drive circuit 33B controlled by the control circuit 33A. Specifically, the control circuit 33A and the lighting device drive circuit 33B are configured on the control circuit board 33, and the liquid crystal drive circuit 27A is configured in the electronic component 29.

  The control circuit 33A sends a control signal to the liquid crystal drive circuit 27A, and the liquid crystal drive circuit 27A displays a predetermined image in the display area AD of the liquid crystal panel 25 based on the control signal. In addition, the control circuit 33A sends a control signal to the illumination device drive circuit 33B, and the illumination device drive circuit 33B supplies predetermined power independently to the first LED 3 and the second LED 4 in the illumination device 11. Further, the control circuit 33A sends a timing signal to the lighting device driving circuit 33B, and the lighting device driving circuit 33B drives the lighting device 11 based on this timing signal, so that the light emission characteristics of the lighting device 11 are driven by liquid crystal. The circuit 27A can be changed in synchronization with the display drive timing. Here, the control circuit 33A and the illumination device drive circuit 33B constitute the illumination color control means.

  In this embodiment, the light emission luminance of the first LED 3 and the second LED 4 of different colors in the illumination device 11 can be controlled independently by driving the illumination device 11 via the illumination device drive circuit 33B by the control circuit 33A. Therefore, the chromaticity of the illumination light irradiated from the illumination device 11 to the liquid crystal panel 25 can be optimized. Further, since the control circuit 33A can control the chromaticity of the light emitted from the illumination device 11 according to the display mode of the liquid crystal panel 25, the chromaticity of the illumination light can be set in association with the display mode, Alternatively, the color rendering properties can be improved and the chromaticity range of the expression mode can be expanded by changing the display mode in association with the display mode.

  For example, once the liquid crystal panel 25 is configured, the transmission filter characteristics of the color filter cannot be changed, but the color reproduction characteristics of the display mode can be changed by changing the emission spectrum distribution of the illumination light. The color rendering properties of the display mode can be set or improved. Further, even when the liquid crystal panel 25 is not provided with a color filter, the display mode can be changed to a pseudo color by changing the emission spectrum of illumination light, for example, black and white display, red black display, green black display, blue black display, etc. Can be changed.

  According to the liquid crystal device 100 of the present embodiment, since the illumination device 11 is provided, it is possible to provide an image with high quality without luminance unevenness and color unevenness.

[Electronics]
Finally, an embodiment of an electronic apparatus equipped with the liquid crystal device will be described with reference to FIG. FIG. 11 is a schematic perspective view showing an appearance of an example of an electronic apparatus according to the present invention. The electronic apparatus 1000 in the illustrated example is an in-vehicle car navigation system, and includes a main body 1010 and a display unit 1020 connected to the main body 1010. The main body 1010 is provided with an operation surface 1011 provided with operation buttons and the like, and an inlet 1012 for a recording medium such as a DVD. The liquid crystal device 100 is stored inside the display unit 1020, and the display by the liquid crystal device 100, that is, the display of the navigation image can be visually recognized on the display screen 1020a of the display unit 1020.

  Since the electronic apparatus 1000 according to the present embodiment is used in a car navigation system, it is necessary to perform a warning display to warn the user that the engine hydraulic pressure is insufficient or the fuel is insufficient. Since the electronic apparatus 1000 includes the liquid crystal device 100 described above, display is performed by the same processing as the liquid crystal device 100 illustrated in FIG. Control is performed so that each first LED 3 of the lighting device 11 is turned on during normal display, and each second LED 4 is turned on during warning display. In this way, white light can be generated by driving only the first LED 3, and red light can be generated by driving only the second LED 4, so that compared to the conventional method in which emission color is obtained by color mixing, Luminous light with little color unevenness and good color rendering can be obtained. Therefore, the red light emission luminance and light intensity necessary for the warning display can be sufficiently ensured, and the user can recognize without overlooking the information displayed in a single color.

  Note that the illumination device 11, the liquid crystal device, and the electronic apparatus of the present invention are not limited to the illustrated examples described above, and it is needless to say that various modifications can be made without departing from the gist of the present invention. For example, the illuminating device 11 is not limited to the one mounted on the liquid crystal device as described above, but may be used as a single luminaire, or integrated with various other devices other than the liquid crystal device. May be used.

  Further, the first LED 3 and the second LED 4 may be LEDs that emit light colors other than those described above, and are appropriately selected according to the purpose.

It is a top view which shows schematic structure of the light-emitting device which concerns on embodiment of this invention. It is a sectional side view which shows schematic structure of the light-emitting device which concerns on embodiment of this invention. It is an internal circuit diagram of a light-emitting device. It is a top view which shows schematic structure of another light-emitting device. It is a top view which shows schematic structure of another light-emitting device. It is a perspective view which shows an example of the illuminating device which concerns on this embodiment. It is a top view which shows schematic structure of a light emission unit. It is a standard xy chromaticity diagram showing a hue area with respect to Munsell hue established by the International Commission on Illumination (CIE: Commision Internationale de l'Eclairage). 1 is a schematic configuration diagram of an electro-optical device according to an embodiment of the invention. It is a schematic block diagram which shows the structure of the control system of the liquid crystal device which concerns on embodiment of this invention. It is a schematic perspective view which shows the external appearance of an example of the electronic device which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Light-emitting device, 3 ... 1st LED (1st light-emitting device), 4 ... 2nd LED (2nd light-emitting device), 5 ... Phosphor, 6 ... Light emitting element circuit, 7 ... 1st electric current supply part (electric current supply) Means), 8 ... second current supply unit (current supply means), 11 ... illumination device, 100 ... liquid crystal device (electro-optical device), 1000 ... electronic device

Claims (11)

A light emitting device in which a plurality of light emitting elements having different emission spectra are arranged in a package,
A first light emitting element that emits light of a predetermined color;
A light emitting element circuit having a second light emitting element that is connected in parallel in the opposite direction to the first light emitting element and emits light of a color different from that of the first light emitting element;
A light-emitting device comprising current supply means capable of switching a current flow direction in a reverse direction with respect to the light-emitting element circuit.     The anode terminal of the first light emitting element and the cathode terminal of the second light emitting element are connected in common to a pair of input / output terminals, and the cathode terminal of the first light emitting element and the second light emitting element The light emitting device according to claim 1, wherein the anode terminal is connected to a pair of output terminals in common.     The light emitting device according to claim 1, wherein the first light emitting element emits blue light and the second light emitting element emits red light.     4. The device according to claim 1, wherein the first light-emitting element and the second light-emitting element have a protective function of preventing currents that are opposite to each other from being supplied to other light-emitting elements. The light-emitting device according to any one of the above.     5. The plurality of first light emitting elements are connected in series, and the plurality of second light emitting elements are connected in series. 5. The light emitting device according to 1.     The light emitting device according to any one of claims 1 to 5, wherein a light emitting surface of the first light emitting element is covered with a phosphor.     7. The phosphor according to claim 1, wherein the phosphor is formed only on the light emission surface of the first light emitting element and is not formed on the second light emitting element. 8. The light-emitting device of description.     The light emitting device according to claim 6, wherein the first light emitting element and the second light emitting element are sealed with a resin containing a phosphor.     9. A lighting device comprising: the light-emitting device according to claim 1; and a light guide plate that converts light emitted from the light-emitting device into planar light.     An electro-optical device comprising: the illumination device according to claim 9; and a light modulation device that modulates light from the illumination device.     An electronic apparatus comprising the electro-optical device according to claim 10.

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