JP2003330109A - Illuminator and projection type display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an illuminator whose illuminating efficiency can be enhanced and a projection type display device which provides bright and high- contrast display. <P>SOLUTION: The illuminator 1 to be used in this projection type display device is provided with an LED array 2 having a plurality of chip LEDs 8R, 8G, 8B, a plurality of tapered rod lenses 3 which are provided in correspondence with respective chip LEDs 8R, 8G, 8B, a rod lens 4 common to the plurality of tapered rod lenses 3 and a light-emission lens 5 for making rays of light entering from the rod lens 4 exit with prescribed outgoing angles. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lighting device and a projection type display device.

[0002]

2. Description of the Related Art Projection-type display devices have been known in which image light is combined using a light modulator such as a liquid crystal light valve, and the combined image light is enlarged and projected on a screen through a projection optical system including a projection lens. Has been. In a lighting device used for this type of projection display device, light emitted from a light source such as a metal halide lamp usually has a non-uniform illuminance distribution in which a central part is bright and a peripheral part is dark. Therefore, in order to equalize the illuminance distribution in the illuminated area, specifically, the liquid crystal light valve, a lighting device for a projection display device has a fly-eye integrator composed of two fly-eye lenses, or a rod-shaped guide. A uniform illumination system such as a rod integrator made of a light body (hereinafter, also referred to as a rod lens) is usually provided. Further, as the light source itself, adoption of a surface emitting light source which is likely to obtain uniform illuminance in the plane is being considered.

[0003]

Conventionally, in order to realize a surface emitting light source, for example, a plurality of light emitting diodes (Light Emitting Diodes) are used.
There has been provided a so-called LED lamp array in which lamps are arranged in an array on a substrate. However, the conventional LED lamp is equipped with a resin lens in which each LED protrudes in a hemispherical shape,
When these were arranged in an array, the light source itself was considerably large. On the other hand, in recent years, chip-type LEDs
(Hereinafter, referred to as a chip LED) has been provided, which has enabled downsizing and thinning of a light source.

However, since the chip LED has a characteristic that the radiation angle distribution is large, there is a problem that the illumination efficiency is poor when illuminating the object to be illuminated. Also,
When used in a projection display device, a large amount of light is incident on the incident surface of an optical modulator such as a liquid crystal light valve from an oblique direction, which causes a dark display and lowers the contrast.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a lighting device capable of improving the lighting efficiency. It is another object of the present invention to provide a projection type display device that can obtain a bright and high-contrast display.

[0006]

In order to achieve the above-mentioned object, a lighting device of the present invention is provided with a light source having a plurality of solid state light emitting elements and corresponding to each of the plurality of solid state light emitting elements. A plurality of tapered light guides in which light from the solid-state light-emitting element is incident from the incident end face and emitted from the emitting end face, and the area of the emitting end face is larger than the area of the incident end face; And an optical element that emits light incident from the body at a predetermined emission angle.

In the illuminating device of the present invention, a surface emitting light source is constituted by a light source having a plurality of solid state light emitting elements.
Since the solid state light emitting element itself has a large emission angle distribution, the light emission angle distribution of the light emitted therefrom remains large only with this light source. However, in the present invention, since the tapered light guide is provided on the emission side of the light source, when the light from the solid-state light emitting element is reflected inside the tapered light guide, it is parallel to the system optical axis. Since it can be bent at an angle close to, the radiation angle distribution can be narrowed. Further, since the optical element is provided on the emission side of the tapered light guide, the light incident from the tapered light guide is emitted at a predetermined emission angle, and the emission angle is adjusted to a predetermined value. It is possible to realize more uniform illumination with high efficiency in the illuminated area. The “system optical axis” is the outgoing optical axis of the entire lighting device.

The tapered light guide may be a columnar light guide made of a material having a refractive index of 1 or more, or a tubular light guide having an inner surface as a reflecting surface. The "columnar light guide" or "tubular light guide whose inner surface is a reflection surface" is a so-called conventional rod lens. According to this structure, the structure of the present invention can be easily realized only by installing the conventional rod lens on the emission side of the light source.

Further, a light guide body having a function of making the illuminance distribution of incident light uniform may be further provided on the emission side of the tapered light guide body. In that case, the light guide may be tapered so that the area of the exit end face is larger than the area of the entrance end face. In the present invention, the tapered light guide can narrow the radiation angle distribution of light, but by providing the light guide on the exit side, the illuminance distribution can be made more uniform. As a result, it is possible to suppress unevenness in display brightness when used as an illumination device of a display device, for example. Further, if this light guide body is tapered, it is possible to further enhance the effect of narrowing the radiation angle distribution while maintaining the effect of making the illuminance distribution uniform.

When the optical element is provided on the exit side of the tapered light guide, one optical element may be provided for a plurality of tapered light guides, or each tapered light guide may be provided. Each may be provided with an optical element. Particularly in the latter case, the emission angle can be controlled for each light flux emitted from each solid-state light emitting element, and more efficient illumination can be performed.

In particular, when an optical element is provided for each tapered light guide, the light emitted from each optical element has a predetermined emission angle, and the light emitted from the plurality of optical elements is at least partially in the illuminated area. It is desirable to have a configuration in which they are superimposed.
By making the light emitted from the plurality of optical elements partially overlap in the illuminated area, each light emitted is bright in the center, for example.
Even if the illuminance distribution is such that the surroundings are dark, the illuminance distributions are canceled out, and it is possible to obtain illumination light with uniform illuminance as a whole. Further, if the light emitted from the plurality of optical elements is all overlapped in the illuminated area, even if there is a variation in brightness among the emitted light, the variation is canceled out, and illumination light with no illuminance unevenness is obtained. be able to.

Further, it is desirable that the optical element corresponding to the solid state light emitting element located at a position deviated from the system optical axis is arranged at a position close to the system optical axis with respect to the emission optical axis of the solid state light emitting element. According to this configuration, since the direction of the optical axis emitted from the optical element approaches the system optical axis, that is, closer to the center of the illuminated area, light is not wasted and more efficient illumination can be provided.

Alternatively, it is desirable that a plurality of solid-state light emitting elements are arranged in a curved surface so as to surround the illuminated area, for example, so that their respective emission optical axes intersect. With this configuration, by arranging the intersection of the respective outgoing optical axes at the center of the illuminated area, it is possible to provide more efficient illumination without wasting light, as in the above case.

Further, a sealing layer having a light transmitting property may be provided on at least the emission surface of the solid state light emitting device. According to this configuration, by providing the sealing layer, it is possible to protect the emission surface of the solid-state light emitting element from mechanical impact or intrusion of moisture, and it is possible to improve reliability.

It is desirable that the side surface of the sealing layer has a tapered shape that is divergent toward the light emission direction. In that case, it is desirable that the side surface of the sealing layer be a reflection surface that guides the inside of the sealing layer and reflects the light reaching the side surface to the sealing layer side. Since the sealing layer has a light-transmitting property, it basically does not hinder the emission of light, but since the solid-state light emitting element has a large emission angle distribution, light emitted at a large emission angle is Total reflection on the surface of the sealing layer,
It may not be emitted to the outside. When such light is guided inside the sealing layer and reaches the side surface of the sealing layer, it has a tapered shape that diverges toward the light emission direction. Is converted into an emission angle closer to vertical to the surface of the sealing layer and reflected, so that light can be emitted to the outside and contribute to illumination.

The plurality of solid state light emitting elements may be integrated in any form. For example, an arbitrary substrate may be used and the plurality of solid state light emitting elements may be installed on one surface of the substrate. With this configuration, a plurality of solid-state light emitting elements can be easily integrated, and the light source can be handled easily.

When a plurality of solid state light emitting devices are mounted on one surface of the substrate, the external terminals of the solid state light emitting devices are led out to the surface of the substrate opposite to the solid light emitting device mounting surface through through holes penetrating the substrate. It is desirable to have a configuration. In the conventional mounting form of a solid state light emitting device, the main body of the solid state light emitting device is mounted on a substrate and the like, and terminals are led out to the outside of the solid state light emitting device body by wire bonding or the like on the mounting surface. This form requires a space for wire bonding around the main body of the solid state light emitting device, and interferes with the installation of the tapered light guide due to interference between the wire and the tapered light guide. May occur.
On the other hand, according to the above configuration, the external terminals of the solid-state light-emitting element are led out through the through holes on the surface of the substrate opposite to the surface on which the solid-state light-emitting element is mounted. It becomes unnecessary, the mounting work becomes easy, and the tapered light guide can be installed without any trouble.

When a conductor forming a part of the external terminal of the solid state light emitting device is provided on the mounting surface of the substrate, it is desirable to cover the conductor with an insulating film. In that case, a tapered light guide can be provided on the insulating film. According to this configuration,
It is possible to prevent problems such as a short circuit of a conductor forming a part of the external terminal with other members. Accordingly, a tapered light guide can be provided on the insulating film, and for example, in the case of a tubular tapered light guide, this can be installed close to the solid-state light emitting element, so The utilization efficiency of the emitted light can be improved.

In the illumination device of the present invention, the plurality of solid state light emitting elements forming the light source may include solid state light emitting elements that emit colored lights of different colors. According to this configuration, it can be used as an illumination device of a color projection type display device of a color sequential drive (color sequential) system, for example. In that case, for example, unlike the conventional three-panel projection type display device using three light valves for each color light,
Only one light valve is required (single plate method), and one lighting system is required. Further, since the color separation optical system and the color synthesis optical system are unnecessary, the number of parts can be greatly reduced, the device configuration can be simplified, and the cost can be reduced.

The projection type display device of the present invention comprises the above-mentioned illumination device of the present invention, an optical modulator for modulating the light from the illumination device, and a projection lens for projecting the light modulated by the optical modulator. It is characterized by having at least. According to this configuration, by including the illumination device of the present invention,
Light with a narrow radiation angle distribution and a uniform illuminance distribution is emitted from the illuminating device, so that it is possible to reproduce a high-contrast image with less uneven brightness.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION [Illumination Device According to First Embodiment] An illumination device according to a first embodiment of the present invention will be described below with reference to FIG. In this embodiment, an example in which a chip LED is used as a solid-state light emitting element that constitutes a light source is shown. FIG. 1 is a schematic diagram showing the overall configuration of the lighting device 1, in which reference numeral 2 is an LED array (light source), 3 is a tapered rod lens (tapered light guide), and 4 is a rod lens (light guide). 5,
Is an emission lens (optical element). Reference numeral 6 indicates a liquid crystal light valve (light modulator) which is an illuminated body.

As shown in FIG. 1, the lighting device 1 of the present embodiment has a plurality of (only three are shown in FIG. 1) chip LEDs 8 on one surface of an arbitrary substrate 7 such as a printed circuit board.
The LED array 2 is configured by mounting R, 8G, and 8B. The mounting form of the chip LEDs 8R, 8G, 8B will be described in later embodiments. As the chip LEDs, an LED 8R capable of emitting R (red) color light, an LED 8G capable of emitting G (green) color light, and an LED 8B capable of emitting B (blue) color light are mounted on one substrate 7. There is.

Then, one chip LED 8R, 8G,
One taper rod lens 3 is provided corresponding to 8B. In the present embodiment, the taper rod lens 3 formed of a tubular mirror arranged so that the inner surface serves as a reflecting surface is used. In addition, a tapered rod lens made of a material having a refractive index of 1 or more, for example, a columnar body such as glass may be used. In FIG. 2, the left side surface of the tapered rod lens 3 is the incident end surface 3a, and the right side surface is the output end surface 3b.
The taper rod lens 3 has a tapered shape that is divergent from the incident end face 3a side toward the emitting end face 3b side.

1 is provided on the exit side of the plurality of tapered rod lenses 3.
Individual rod lenses 4 are provided. In the present embodiment, the rod lens 4 is also composed of a tubular mirror arranged so that its inner surface serves as a reflecting surface. The outermost mirror of the plurality of taper rod lenses 3 and the rod lens 4
Is directly connected to the mirror. Further, an exit lens 5 composed of a normal convex lens is provided at a position apart from the rod lens 4 on the exit side of the rod lens 4.

In the illuminating device 1 of the present embodiment, since the taper rod lens 3 is provided on the emission side of the LED array 2 having the plurality of chips LEDs 8R, 8G, 8B, the chips LEDs 8R, 8G, 8B are used. The light is reflected on the inner surface while being guided inside the tapered rod lens 3, and the light L having an angle close to parallel to the system optical axis S is obtained.
The radiation angle distribution can be narrowed. Since the rod lens 4 is provided on the exit side of the tapered rod lens 3, the illuminance distribution can be made uniform. further,
Since the emission lens 5 is provided on the emission side of the rod lens 4, the light incident on the emission lens 5 is emitted at a predetermined emission angle, and the emission angle is appropriately adjusted to the liquid crystal light valve 6. Efficient and uniform illumination can be realized. As a result, when it is used as an illumination device of a projection display device, for example, it is possible to improve illumination efficiency, improve contrast, and suppress unevenness in display brightness.

Further, a liquid crystal light valve 6 which is an object to be illuminated.
When the outer diameter of the exit end surface of the rod lens 4 is set to be smaller than the outer diameter of the liquid crystal, and the enlarged illumination optical system is used, the incident angle when light enters the liquid crystal light valve 6 is inversely proportional to the enlargement ratio. The angle of incidence on the light valve 6 can be reduced, and the illumination efficiency is further improved, and at the same time, the contrast is further improved.

[Illumination Device According to Second Embodiment] An illumination device according to a second embodiment of the present invention will be described below with reference to FIGS. FIG. 2 is a schematic diagram showing the overall configuration of the lighting device of the present embodiment, but the same components as those in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 2, the illumination device 11 of the present embodiment has a plurality of chip LEDs 8R, 8 on one surface of the substrate 7.
G and 8B are mounted, and the LED array 2 is configured. Further, one taper rod lens 3 is provided corresponding to one chip LED 8R, 8G, 8B. The configuration so far is almost the same as that of the first embodiment. In the first embodiment, the rod lens 4 and the exit lens 5 are sequentially installed on the exit side of the taper rod lens 3, but in the present embodiment, there is no rod lens, and the exit end surface of each taper rod lens 3 is normally formed. The exit lens 12 which is a convex lens is directly installed. Air may be present in the internal space of the taper rod lens 3, or a material having a lower refractive index than the exit lens 12 may be filled. Then, the outgoing light L emitted from each outgoing lens 12
The output angle of the output light L from each output lens 12 is set so that all the liquid crystal light valves 6 are superposed on each other.

Also in this embodiment, it is possible to efficiently and uniformly illuminate the liquid crystal light valve 6. For example, when the liquid crystal light valve 6 is used as an illumination device for a projection type display device, the contrast is improved and the display brightness is improved. It is possible to obtain the same effect as that of the first embodiment such that unevenness can be suppressed.

Further, in the case of the present embodiment, since the output lens 12 is provided for each taper rod lens 3, the output angle can be controlled for each light beam emitted from each chip LED 8R, 8G, 8B. Therefore, it is possible to perform more efficient lighting. Specifically, in order to make the outgoing lights emitted from the respective outgoing lenses 12 all overlap on the entire surface of the liquid crystal light valve 6, for example, as shown in FIG. Emitting lens 12 corresponding to the chip LEDs 8R, 8B in
The center C1 of R and 12B may be arranged at a position closer to the system optical axis S with respect to the emission optical axis C2 of each chip LED 8R and 8B. Alternatively, as shown in FIG. 4, a plurality of chip LEDs 8R, 8G, 8B are arranged in a curved surface so as to surround the liquid crystal light valve 6, and each chip LED 8R, 8G is arranged.
The output optical axes C3 from G and 8B may intersect at substantially the center of the liquid crystal light valve 6. Multiple chips L
The light emitted from the EDs 8R, 8G, and 8B is only partially overlapped on the liquid crystal light valve 6, and the center of each light is bright,
You can offset the illuminance distribution that the surroundings are dark,
In the case of this embodiment, a plurality of chip LEDs 8R, 8G,
Since the emitted light from 8B is all superimposed on the liquid crystal light valve 6, even if there is a luminance variation among the plurality of chip LEDs 8R, 8G, 8B, the variation is canceled out,
It is possible to obtain illumination light without uneven illuminance.

[Illumination Device According to Third Embodiment] An illumination device according to a third embodiment of the present invention will be described below with reference to FIGS. FIG. 5 is a schematic diagram showing the overall configuration of the lighting device of the present embodiment, but the same components as those of the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 5, the lighting device 17 of the present embodiment has a plurality of chip LEDs 8R, 8 on one surface of the substrate 7.
G and 8B are mounted, and the LED array 2 is configured. Then, the plurality of chip LEDs 8R, 8G, 8B are sealed with a translucent material such as acrylic resin,
The sealing layer 18 is formed. Side surface 18a of sealing layer 18
Is flat and has a tapered shape that is divergent toward the light emission direction, and a mirror 19 having an inner surface as a reflection surface is provided on the side surface 18a.

In the case of this embodiment, since the sealing layer 18 has a light-transmitting property, there is basically no problem in emitting light. However, the chip LEDs 8R, 8G, 8
Since the emission angle distribution of B is large, light emitted at a large emission angle may be totally reflected on the surface of the sealing layer 18, and may not be emitted to the outside of the sealing layer 18. As a measure against this, the side surface of the sealing layer 18 has a taper shape that is divergent toward the light emission direction, and is a reflecting surface by the mirror 19, so that the light is sealed as indicated by the arrow L1. Since it is converted into an emission angle that is closer to vertical to the surface of the stop layer 18, it can be emitted to the outside of the sealing layer 18 and contribute to illumination.

Although the side surface 18a of the sealing layer 18 is flat in FIG. 5, the side surface 18b of the sealing layer 18 may be curved as shown in FIG. 6 instead of this structure. In this way, the emission angle of the light reflected by the side surface of the sealing layer 18 to the outside of the sealing layer can be adjusted appropriately.

Further, as shown in FIG. 7, a taper rod lens 24 may be further added to the emitting side of the sealing layer 18 of the illuminating device 17 shown in FIG. This makes it possible to further narrow the radiation angle distribution of the light emitted from the lighting device 23. Further, the exit lens 26 may be directly installed on the exit side of the tapered rod lens 24 of the illumination device 23 shown in FIG. 7 as shown in FIG. 8, or the rod lens 28 may be installed directly as shown in FIG. You may.

[Illumination Device According to Fourth Embodiment] An illumination device according to a fourth embodiment of the present invention will be described below with reference to FIGS. Although the overall configuration of the lighting device has been described in the above embodiment, the mounting structure of the chip LED will be described in this embodiment. FIG. 10 is a sectional view showing the mounting structure of the chip LED of this embodiment.

As shown in FIG. 10, the mounting structure of the chip LED 8 of the present embodiment has a surface mounting type chip LED main body on the upper surface of the substrate 7 such that the light emitting surface is on the upper side and the electrode forming surface is on the lower side. 8a is mounted. The substrate 7 in the present embodiment is, for example, a double-sided printed wiring board, conductor patterns 29a and 29b are formed on the upper and lower surfaces, and the conductor patterns 29a and 29b are formed on the substrate 7.
Are electrically connected via a through hole 30 penetrating through. Then, the two conductor patterns 29 on the upper surface of the substrate 7
The positive and negative electrodes on the lower surface side of the chip LED body 8a are connected to a, respectively. With this configuration, the chip LE
The external terminal of D8 is led out to the surface opposite to the mounting surface of the substrate 7. The conductor pattern 29a on the upper surface of the substrate is covered with an insulating film 31 such as a resist film, and the taper rod lens 3 is provided on the insulating film 31.

In the conventional mounting form of the chip LED, the chip LED main body is mounted on a substrate or the like, and the external terminals are led out from the electrodes by wire bonding or the like on the mounting surface. With this configuration, a space for wire bonding is required around the chip LED body, which may hinder the installation of the taper rod lens. On the other hand, according to the configuration of this embodiment, the substrate 7
Since the external terminals are led out to the surface opposite to the mounting surface of the chip LED 8 through the through hole 30, wire bonding on the mounting surface is not required and high density mounting can be achieved. In addition, the conductor pattern 29a on the upper surface of the substrate
Are covered with the insulating film 31, and the taper rod lens 3 is provided on the insulating film 31, so that the taper rod lens 3 is prevented from being short-circuited with another member or the taper rod lens 3 itself, and at the same time, the taper is reduced. The rod lens 3 can be installed close to the chip LED 8. As a result, the utilization efficiency of the light emitted from the chip LED 8 can be improved.

As shown in FIG. 11, the upper surface of the chip LED 8 and the insulating film 31 of the lighting device 33 shown in FIG. 10 is covered with the sealing layer 18 similar to that shown in FIGS. May be. As a result, the chip LED 8 and the conductor pattern 29a can be reliably protected.

The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, in the above-described embodiment, the LED is used as the solid-state light emitting element that constitutes the light source.
An electroluminescence element or the like can be used. Further, although a normal convex lens is used as the optical element for controlling the emission angle to the illuminated body, an aspherical lens such as a Fresnel zone plate, a hologram, a diffractive element or the like can be used.

[Projection Display Device According to First Embodiment] A projection display device according to a first embodiment of the present invention will be described below with reference to FIG.
2 will be described. The projection type display device of the present embodiment is an example of a transmission type liquid crystal projector using a transmission type liquid crystal light valve as a light modulator. FIG. 12 is a schematic configuration diagram of the liquid crystal projector of this embodiment.

As shown in FIG. 12, the liquid crystal projector 41 of the present embodiment has the illuminating device 1 of the first embodiment shown in FIG. 1 and the liquid crystal light valve 6. That is, a plurality of chips LE capable of emitting R, G, and B color lights
LED array 2 in which D8R, 8G, 8B are arranged in a plane, a plurality of taper rod lenses 3 installed corresponding to the chip LEDs 8R, 8G, 8B, and a common arrangement for the plurality of taper rod lenses 3 Rod lens 4
An exit lens 5, a liquid crystal light valve 6 that synthesizes an image by modulating each color light incident from the exit lens 5, and a projection lens 44 that magnifies and projects the image synthesized by the liquid crystal light valve 6 onto a screen 43. It is composed of In addition, in order to further increase the light utilization efficiency, a configuration may be provided in which a PBS (polarization beam splitter) array that aligns the light from the chip LEDs 8R, 8G, and 8B with the polarized light used for display by the liquid crystal light valve 6 is provided.

The LED array 2 is connected to a light source drive circuit (not shown), and each LED is connected by this light source drive circuit.
The timing at which 8R, 8G, and 8B emit light is controlled, and, for example, R, G, B, and R from each LED 8R, 8G, and 8B.
G, B, and so on are configured to be capable of emitting colored light in time sequence.

The liquid crystal light valve 6 has a thin film transistor as a pixel switching element.
(hereinafter, abbreviated as TFT), a TN mode active matrix type transmissive liquid crystal cell 45 is used, and an incident side polarization plate 46 and an emission side polarization plate 47 are transmitted to the outer surface of the liquid crystal cell 45. The axes are arranged so as to be orthogonal to each other. For example, in the off state, the s-polarized light incident on the liquid crystal light valve 6 is converted into p-polarized light and emitted, while in the on-state, the light is blocked.

The liquid crystal light valve 6 is connected to a liquid crystal light valve drive circuit (not shown), and this liquid crystal light valve drive circuit can drive the liquid crystal light valve 6 in time sequence in accordance with each incident color light. The structure is possible. Further, the projection display device 41 of the present embodiment is provided with a synchronization signal generation circuit (not shown), and this synchronization signal generation circuit generates a synchronization signal to cause the light source drive circuit and the liquid crystal light valve drive circuit to operate. By inputting, the timing for emitting the color light from each of the LEDs 8R, 8G, 8B and the timing for driving the liquid crystal light valve 6 corresponding to the color light are synchronized.

That is, in the projection type display device 41 of the present embodiment, one frame is time-divided and the LEDs 7r, 7g,
The LEDs 7r, 7g, 7g, 7g, and 7b are synchronized with the timing of emitting the colored light of each of the LEDs 7r, 7g, 7b and the timing of driving the liquid crystal light valve 5 by sequentially emitting the respective colored lights of R, G, B from 7b. The liquid crystal light valve 5 is sequentially driven in time corresponding to the color light emitted from 7b, and the color image is synthesized by outputting the image signal corresponding to the color light emitted from each of the LEDs 7r, 7g, 7b. It is possible.

The projection type display device 41 of the present embodiment employs a drive system called a so-called "color sequential drive (color sequential) system". Therefore,
Unlike the conventional three-panel type projection display device that uses three liquid crystal light valves for each color light, only one liquid crystal light valve 6 is required (single plate type), and the liquid crystal light valve 6 is illuminated. The device 1 also needs only one system. Further, since the color separation optical system and the color synthesis optical system are unnecessary, the number of parts can be greatly reduced, the device configuration can be simplified, and the cost can be reduced. Further, since the liquid crystal light valve 6 is irradiated with light having a narrow radiation angle distribution and a uniform illuminance distribution from the illumination device 1, it is possible to reproduce a high-contrast image with less uneven brightness.

[Projection Display Device According to Second Embodiment] A projection display device according to a second embodiment of the present invention will be described below with reference to FIG.
This will be described with reference to FIG. The projection type display device of the present embodiment is an example of a reflection type liquid crystal projector using a reflection type liquid crystal light valve as a light modulator. FIG. 13 is a schematic configuration diagram of the liquid crystal projector of this embodiment.

As shown in FIG. 13, the liquid crystal projector 51 of the present embodiment has the illumination device 11 and the liquid crystal light valve 52 of the second embodiment shown in FIG. That is, a plurality of chips L capable of emitting R, G, and B color lights
The LED array 2 in which the EDs 8R, 8G, 8B are arranged in a plane, the plurality of taper rod lenses 3 installed corresponding to the chip LEDs 8R, 8G, 8B, and the emission end surface of each taper rod lens 3 are provided. The exit lens 12, a liquid crystal light valve 52 that modulates each color light incident from the exit lens 12, and synthesizes an image, and a liquid crystal light valve 52.
A projection lens 44 for enlarging and projecting the combined image on the screen 43 is roughly configured. For the liquid crystal light valve 52, a TN mode active matrix reflective liquid crystal cell 53 using TFTs is used.
A polarizing plate 54 is provided.

Also in the liquid crystal projector 51 of the present embodiment, by providing the illumination device 11 of the above embodiment, it is possible to reproduce a high-contrast image with little brightness unevenness and the liquid crystal of the first embodiment. The same effect as the projector can be obtained.

The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, in the above embodiment, red light is provided in one lighting device,
An example of a single plate type color-sequential drive liquid crystal projector in which LEDs capable of emitting green light and blue light are mixed is given, but three lighting devices capable of emitting red light, green light, and blue light are provided. A three-plate type liquid crystal projector having a color combining optical system such as a cross dichroic prism may be used. Alternatively, it may be a three-plate liquid crystal projector that includes one illumination device that can emit white light and that includes a color separation optical system such as a dichroic mirror and a color combining optical system such as a cross dichroic prism. Further, in the above-described embodiment, the example in which the illumination device of the present invention is used for the projection type display device is shown, but it is also possible to use it for the direct view type display device.

[0052]

As described in detail above, according to the illumination device of the present invention, it is possible to realize efficient and more uniform illumination of the illuminated area. Further, according to the projection type display device of the present invention, light having a narrow radiation angle distribution and a uniform illuminance distribution is emitted from the illuminating device, so that it is possible to reproduce a high-contrast image with less uneven brightness. You can

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing a lighting device according to a first embodiment of the present invention.

FIG. 2 is a schematic configuration diagram showing a lighting device of a second embodiment of the present invention.

FIG. 3 is a schematic configuration diagram showing a modified example of an emission lens of the illumination device.

FIG. 4 is a schematic configuration diagram showing a modified example of the arrangement of chip LEDs of the illumination device.

FIG. 5 is a schematic configuration diagram showing a lighting device of a third embodiment of the present invention.

FIG. 6 is a schematic configuration diagram showing a modified example of a side surface shape of a sealing layer of the lighting device.

FIG. 7 is a schematic configuration diagram showing a modified example of the illumination device.

FIG. 8 is a schematic configuration diagram showing a modified example of the lighting device.

FIG. 9 is a schematic configuration diagram showing a modified example of the illumination device.

FIG. 10 is a schematic configuration diagram showing an illumination device according to a fourth embodiment of the present invention.

FIG. 11 is a schematic configuration diagram showing a modified example of the illumination device.

FIG. 12 is a schematic configuration diagram of a liquid crystal projector that is a projection type display device according to the first embodiment of the present invention.

FIG. 13 is a schematic configuration diagram of a liquid crystal projector which is a projection type display device according to a second embodiment of the present invention.

[Explanation of symbols]

1,11,13,15,17,21,23,25,2
7,33 Illumination device 2 LED array (light source) 3,24 Tapered rod lens (tapered light guide) 4,28 Rod lens (light guide) 5,12,12r, 12b, 26 Emission lens (optical element) 6 , 52 liquid crystal light valve (illuminated area, light modulator) 7 substrate 8, 8R, 8G, 8B chip LED (solid-state light emitting element) 18 sealing layers 19, 22 mirrors 29a, 29b conductor pattern 30 through hole 31 insulating film 41 , 51 Liquid crystal projector 44 Projection lens

Front page continuation (51) Int.Cl. ⁷ Identification code FI theme code (reference) G02F 1/13 505 G03B 21/00 D 3K042 1/13357 H01L 33/00 M 5F041 G03B 21/00 N H01L 33/00 F21Y 101: 02 F21M 1/00 R // F21Y 101: 02 F term (reference) 2H042 AA02 AA18 AA26 2H052 BA02 BA03 BA09 BA14 2H088 EA13 EA15 EA16 HA24 HA28 MA06 2H091 FA26X FA26Z FA45X FA45Z LA17 LA30 MA04 A01A02 A01 A01 A01 A02 BA05 BA11 BC42 BC50 CA40 3K042 AA01 AC06 BC08 BC09 5F041 AA06 DA13 DA14 DA36 DA43 DA78 EE25 FF11

Claims (17)

[Claims] 1. A light source having a plurality of solid state light emitting devices, and light sources provided corresponding to each of the plurality of solid state light emitting devices. Light from the solid state light emitting devices enters from an incident end face and is emitted from an emitting end face. A plurality of tapered light guides having a larger area of the exit end surface than the area of the entrance end surface;
An illumination device, comprising: an optical element that emits the light incident from the tapered light guide at a predetermined emission angle. 2. The tapered light guide is a columnar light guide made of a material having a refractive index of 1 or more, or a tubular light guide having an inner surface as a reflecting surface. The lighting device according to claim 1. 3. The illumination according to claim 1, further comprising a light guide body having a function of making an illuminance distribution of incident light uniform on an emission side of the tapered light guide body. apparatus. 4. The illumination device according to claim 3, wherein the light guide is tapered such that the area of the exit end face is larger than the area of the entrance end face. 5. The optical element is provided on the emission side of each of the tapered light guides, respectively.
Or the illumination device according to 2. 6. The light emitted from each of the optical elements has a predetermined emission angle, and the light emitted from the plurality of optical elements is at least partially overlapped in the illuminated area. Illumination device described. 7. The optical element corresponding to the solid-state light-emitting element at a position deviated from the system optical axis is arranged at a position near the system optical axis with respect to the emission optical axis of the solid-state light-emitting element. The lighting device according to claim 5 or 6, characterized in that. 8. The lighting device according to claim 5, wherein the plurality of solid-state light emitting elements are arranged so that their emission optical axes intersect with each other. 9. The lighting device according to claim 1, wherein a sealing layer having a light-transmitting property is provided on at least the emission surface of the solid-state light emitting element. 10. The lighting device according to claim 9, wherein a side surface of the sealing layer has a tapered shape that is divergent toward a light emission direction. 11. The side surface of the sealing layer is a reflection surface that guides the inside of the sealing layer and reflects the light reaching the side surface toward the sealing layer side. The illumination device according to 10. 12. The lighting device according to claim 1, wherein the plurality of solid-state light emitting elements are provided on one surface of a substrate. 13. The solid-state light-emitting device is mounted on one surface of the substrate, and the solid-state light-emitting device is mounted on a surface of the substrate opposite to the solid-state light-emitting device mounting surface through a through hole penetrating the substrate. The lighting device according to claim 12, wherein an external terminal is led out. 14. The mounting surface of the substrate is provided with a conductor forming a part of an external terminal of the solid-state light-emitting element, and the conductor is covered with an insulating film.
The lighting device according to. 15. The lighting device according to claim 14, wherein the tapered light guide is provided on the insulating film. 16. The lighting device according to claim 1, wherein the plurality of solid state light emitting elements forming the light source include solid state light emitting elements that emit colored lights of different colors. 17. The illumination device according to claim 1, an optical modulator that modulates the light from the illumination device, and a projection lens that projects the light modulated by the optical modulator. A projection-type display device comprising at least.