JP2004354880A - Lighting system and projection display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lighting system that can be downsized by improving use efficiency of light emitted from a light source, and to provide a projection display device. <P>SOLUTION: The lighting systems 11r, 11g and 11b used for lighting an area to be lighted comprises light sources 12r, 12g and 12b, and a first reflection means 16 arranged on the periphery of a prescribed area provided forward of light sources 12r, 12g and 12b. The first reflection means 16 reflects light separated from the prescribed area toward the light sources 12r, 12g and 12b. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a lighting device and a projection display device. In particular, the present invention relates to a technique for improving the use efficiency of light emitted from a light source and reducing the size of an apparatus.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, a lighting device used for a projection display device condenses light emitted from a light emitting element with a lens and irradiates the light toward a light valve.
For example, when an LED having a large light-emitting portion area is used as the light-emitting element, the emission angle region is widened, and light emitted at a wide angle is condensed by a condenser lens and is irradiated toward a light valve. . However, light incident on the outside of the entrance pupil of the condenser lens does not contribute to illumination of the light valve, and is not only lost but also becomes stray light, which causes deterioration in display quality.
[0003]
As an illuminating device that solves the above-described problem, an illuminating device that is generally formed of a light emitting element, a mold resin that seals the light emitting element, and a light reflecting portion provided on a back surface of the mold resin is known.
In the mold resin, a direct emission region for directly emitting the light of the light emitting element to the outside around the optical axis at the front interface, and a total reflection region for totally reflecting the light of the light emitting element around the direct emission region are formed. The direct emission area is formed in a convex lens shape.
[0004]
Part of the light emitted from the light emitting element is emitted forward due to a lens action when passing directly through the emission area. Another part of the light emitted from the light emitting element is totally reflected by the total reflection area, then reflected by the light reflection section, and emitted forward from the total reflection area (for example, see Patent Document 1).
[0005]
[Patent Document 1]
JP-A-2002-94129 (pages 8-9, FIG. 3)
[0006]
[Problems to be solved by the invention]
As described above, in the conventional lighting device, the light emitted at a large angle with respect to the optical axis is totally reflected in the total reflection area and returned to the rear, and further reflected by the reflecting mirror and taken out forward. There was a problem that the size was increased by the size of the reflecting mirror.
[0007]
SUMMARY An advantage of some aspects of the invention is to provide a lighting device and a projection display device which can improve the use efficiency of light emitted from a light source and can be reduced in size. With the goal.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, an illuminating device according to the present invention is used for illuminating an illuminated area, comprising: a light source; and a first reflection device disposed around a predetermined area in front of the light source. Means, and wherein the first reflecting means reflects light deviating from the predetermined area toward the light source.
[0009]
That is, in the lighting device of the present invention, the light emitted forward from the light source has various angles with respect to the optical axis, and a part of the light propagates forward in a predetermined area and travels toward the illuminated area. The remaining light deviates from the predetermined area and enters the first reflecting means, and is reflected back toward the light source. A part of the light returned to the light source is reflected forward by the light source, and another part is absorbed by the light source, emits light again, and is emitted forward. Part of the light propagating forward again passes through the predetermined area, and the rest is reflected by the first reflection means, and the above-described process is repeated.
Therefore, the light emitted from the light source is reflected by the first reflection means and the light source until it propagates through the predetermined region, so that the light use efficiency is improved.
Further, unlike the conventional example in which the light emitted from the light source is totally reflected in a direction away from the optical axis and is reflected forward by the light reflecting portion, the first reflecting means reflects the light emitted from the light source toward the light source. Therefore, the size can be reduced.
[0010]
In order to realize the above configuration, more specifically, a second reflector is provided behind the light source, and the second reflector is reflected by the first reflector and propagates backward. It is desirable to reflect light forward.
According to this configuration, since the light emitted backward from the light source can be reflected forward, the utilization efficiency of the light emitted from the light source can be improved. Furthermore, since the light transmitted through the light source among the light reflected by the first reflection means and incident on the light source can be reflected forward, the utilization efficiency of the light deviating from the predetermined region can be improved. it can.
[0011]
In order to realize the above configuration, more specifically, the first reflecting means is formed in an annular shape around the optical axis, and approaches the light source as going outward from the optical axis. It is desirable that the surface formed to be inclined and that reflects light from the light source be a flat surface.
According to this configuration, light emitted from the light source and incident on the first reflection unit can be reflected on the light source.
Further, since the light reflecting surface is formed as a flat surface, less labor is required for processes such as processing and polishing, and the manufacturing can be facilitated.
[0012]
In order to realize the above configuration, more specifically, it is preferable that the first reflecting means is formed in an annular shape with the optical axis as a center, and the light reflecting surface is a concave curved surface. More desirably, the concave surface has an aspherical shape that reflects all light from the light source to the light source.
According to this configuration, almost all of the light emitted from the light source and incident on the first reflecting means can be reflected on the light source. Therefore, it is possible to further increase the ratio of light emitted from the light source, propagated in the predetermined area, and irradiated to the illuminated area, that is, the light use efficiency.
[0013]
In order to realize the above configuration, it is desirable that the first reflecting means is formed of a light retroreflector. More specifically, it is desirable that the light retroreflector is constituted by a corner cube array in which a plurality of pyramidal corner cubes are arranged.
According to this configuration, the light retroreflector constituted by the corner cube array in which a plurality of corner cubes are arranged can reflect the incident light in substantially the same direction as the incident direction. The light can be reflected to the light source even if the arrangement accuracy of the light source is reduced. Therefore, the labor for arranging the first reflecting means can be reduced, and the manufacturing can be facilitated.
[0014]
In order to realize the above configuration, more specifically, the light retroreflector may be a bead aggregate in which a plurality of spherical beads are arranged.
According to this configuration, since the bead aggregate in which a plurality of spherical beads that are relatively easy to manufacture are arranged becomes the light retroreflector, the first reflection unit can be easily manufactured.
[0015]
In order to realize the above-mentioned configuration, a third reflection unit may be provided around the light source to reflect light propagating backward to the front.
According to this configuration, of the light that is reflected by the first reflection means and propagates backward, the light spilled around without being incident on the light source is incident on the third reflection means and is reflected forward. In other words, light spilled around the light source can also be used, so that the ratio of light emitted from the light source and propagated in the predetermined area and irradiated to the illuminated area, that is, the light use efficiency is further increased. can do.
[0016]
In order to realize the above configuration, more specifically, it is preferable that the third reflecting means is formed in an annular shape around the optical axis, and the light reflecting surface is a flat surface.
According to this configuration, light spilled around the light source can be used, so that the light use efficiency can be further increased.
Further, since the light reflecting surface is formed as a flat surface, less labor is required for processes such as processing and polishing, and the manufacturing can be facilitated.
[0017]
In order to realize the above configuration, more specifically, it is preferable that the third reflecting means is formed in an annular shape around the optical axis, and the light reflecting surface is a concave curved surface.
According to this configuration, almost all of the light reflected by the first reflection means and spilled around the light source can be reflected to the predetermined area in front. Therefore, it is possible to further increase the ratio of light emitted from the light source, propagated in the predetermined area, and irradiated to the illuminated area, that is, the light use efficiency.
[0018]
In order to realize the above configuration, the light source may be a light emitting diode (hereinafter, referred to as an LED).
At present, LEDs with high output for each color light such as R, G, B, etc. are provided, and since these kinds of LEDs can be arranged in an array in a plane or a curved surface, the size of the light source can be reduced. be able to. Therefore, a light source suitable for the lighting device of the present invention can be obtained.
[0019]
In order to realize the above configuration, a condensing lens may be provided in the predetermined area, and the light incident on the predetermined area may be condensed on the illuminated area by the condensing lens.
According to this configuration, the light incident on the predetermined area is condensed on the illuminated area by the condenser lens without leakage, so that the ratio of the light emitted from the light source and applied to the illuminated area, that is, Usage efficiency can be further increased.
[0020]
A lighting device having a light source, a light modulating means for modulating light from the lighting device, and a projecting means for projecting the light modulated by the light modulating means. The lighting device of the present invention can be provided.
By using the above-described lighting device for the lighting device of the projection display device, the utilization efficiency of light emitted from the light source can be improved, and the size of the lighting device can be reduced, and thus the size of the projection display device can be reduced. it can.
[0021]
BEST MODE FOR CARRYING OUT THE INVENTION
[First Embodiment]
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.
In this embodiment, an example of a three-panel projection type liquid crystal display device will be described. FIG. 1 is a schematic diagram showing the overall configuration of a projection display device 10, in which reference numerals 11r, 11g, 11g denote illumination devices, 31, 32, 33 liquid crystal light valves (light modulating means), 35 a cross dichroic prism, 41 is a projection lens (projection means).
[0022]
As shown in FIG. 1, the projection display device 10 of the present embodiment includes illumination devices 11r, 11g, and 11b capable of emitting R, G, and B color lights, and illumination devices 11r, 11g, and 11b, respectively. Liquid crystal light valves 31, 32, and 33 corresponding to the emitted R, G, and B color lights, a cross dichroic prism 35 that combines the respective color lights modulated by the liquid crystal light valves 31, 32, and 33, and a combined light beam And a projection lens 41 that projects the image on the screen S.
[0023]
FIG. 2 is a schematic diagram illustrating a configuration of the lighting device of the present embodiment.
As shown in FIGS. 1 and 2, the lighting devices 11r, 11g, and 11b include LED chips (light sources) 12r, 12g, and 12b that emit R, G, and B color lights, respectively, and a lead frame 13p that includes electrodes p. , An electrode p, a lead frame 13q, a bonding wire 14, a condenser lens 18, and a reflection ring (first reflection means) 16.
On the upper end surface of the electrode p13p, a pedestal (second reflecting means) 17 on which the LED chips 12r, 12g, 12b are placed is formed. The pedestal 17 is formed in a concave curved surface, and the surface is formed by an LED. It is formed to reflect light emitted from the chips 12r, 12g, 12b. Note that the shape of the base 17 may be formed in various shapes such as a spherical shape, an aspherical shape, a flat surface, and a shape obtained by combining flat surfaces.
[0024]
The upper surfaces of the LED chips 12r, 12g, 12b and the electrodes q13q are electrically connected by bonding wires 14, and the lower surfaces of the LED chips 12r, 12g, 12b and the base 17 are electrically conductive adhesive ( (Not shown), electrical connection and fixation are performed.
A condenser lens 18 is disposed between the LED chips 12r, 12g, 12b and the liquid crystal light valves 31, 32, 33, and the center axis of the condenser lens 18 and the optical axis of each of the LED chips 12r, 12g, 12b in the color light emission direction. They are arranged to match. A reflection ring 16 is arranged between the LED chips 12r, 12g, 12b and the condenser lens 18, and the reflection ring 16 is arranged so that its central axis coincides with the optical axis. The reflection ring 16 is formed in an aspherical shape with a concave surface on the side of the LED chips 12r, 12g, 12b, and this aspherical shape reflects all the light incident on the reflection ring 16 into the LED chips 12r, 12g, It is formed in a shape reflecting on 12b.
[0025]
The liquid crystal light valves 31, 32, and 33 each include a liquid crystal panel, an incident-side polarizing plate (not shown), and an emission-side polarizing plate (not shown). 2. Description of the Related Art A TN (Twisted Nematic) mode active matrix type transmissive liquid crystal cell using a Thin Film Transistor (hereinafter abbreviated as TFT) is used.
The cross dichroic prism 35 is formed by laminating four right angle prisms, and a dielectric multilayer film that reflects red light and a dielectric multilayer film that reflects blue light are formed in a cross shape on the inner surface.
[0026]
Next, the operation of the projection display device 10 having the above configuration will be described.
The color lights R, G, and B emitted from the illumination devices 11r, 11g, and 11b respectively enter the liquid crystal light valves 31, 32, and 33 corresponding to the color lights, as shown in FIG. Each of the incident color lights is modulated by the liquid crystal light valves 31, 32, and 33 and emitted to the cross dichroic prism 35. The modulated color lights are combined in the cross dichroic prism 35 and output to the projection lens 41. The projection lens 41 enlarges and projects the combined color lights toward the screen S.
[0027]
Next, the operation of the lighting devices 11r, 11g, and 11b, which are features of the present invention, will be described.
The LED chips 12r, 12g, and 12b supplied with current from the lead frame 13p and the lead frame 13q emit the corresponding R, G, and B color lights in all directions, as shown in FIGS. . Among them, the color light emitted backward enters the base 17 and is reflected forward, transmits through the LED chips 12r, 12g, and 12b and propagates forward.
[0028]
Of the color lights propagating forward, the light incident on the condenser lens 18 is emitted so as to be condensed on the liquid crystal light valves 31, 32, 33.
The light that has propagated in the direction deviating from the condenser lens 18 enters the reflection ring 16 and is reflected toward the LED chips 12r, 12g, and 12b. Part of each color light incident on the LED chips 12r, 12g, 12b is absorbed by a light emitting layer (not shown) of the LED chips 12r, 12g, 12b, and the remaining color light is transmitted without being absorbed.
[0029]
Each color light absorbed by the light emitting layer gives the energy of the electrons of the light emitting layer to an excited state, and is emitted again as each color light when the excited state of the electrons is released. Each color light transmitted through the LED chips 12r, 12g, and 12b is incident on the pedestal portion 17, reflected forward, transmitted through the LED chips 12r, 12g, and 12b again, and propagates forward.
[0030]
According to the above configuration, each color light emitted from the LED chips 12r, 12g, and 12b is reflected between the base 17, the reflection ring 16, and the LED chips 12r, 12g, and 12b until entering the condenser lens 18. are doing. That is, each color light is not lost in the illumination devices 11r, 11g, and 11b until it is transmitted through the condenser lens 18 and extracted, so that the light use efficiency can be increased.
[0031]
By providing the condenser lens 18, it is possible to irradiate the liquid crystal light valves 31, 32 and 33 without diffusing all of the respective color lights emitted from the illumination devices 11 r, 11 g and 11 b. That is, loss of each color light can be prevented between the lighting devices 11r, 11g, and 11b and the liquid crystal light valves 31, 32, and 33, and the light use efficiency can be increased.
[0032]
Since the reflection ring 16 has a light reflecting surface formed in an aspherical shape, almost all of the color lights incident on the reflection ring 16 can be reflected on the LED chips 12r, 12g, and 12b. Therefore, the ratio of each color light emitted from the LED chips 12r, 12g, and 12b and irradiated on the liquid crystal light valves 31, 32, and 33, that is, the light use efficiency can be further increased.
[0033]
In addition, since the reflection ring 16 reflects the light emitted from the LED chips 12r, 12g, and 12b toward the LED chips 12r, 12g, and 12b, the reflection ring 16 is better than the conventional lighting device that improves the light use efficiency. Also, the size of the lighting devices 11r, 11g, and 11b can be reduced. As a result, the size of the projection display device 10 can be reduced.
[0034]
[Second embodiment]
Next, a second embodiment of the present invention will be described with reference to FIGS.
The basic configuration of the projection display device of the present embodiment is the same as that of the first embodiment, but the configuration of the illumination device is different from that of the first embodiment. Therefore, in this embodiment, only the periphery of the lighting device will be described with reference to FIGS. 3 and 4, and the description of the liquid crystal light valve and the like will be omitted.
FIG. 3 is a schematic diagram illustrating a configuration of the lighting device of the present embodiment.
As shown in FIG. 3, the illumination devices 50r, 50g, and 50b have a reflection ring (first reflection means) 51 disposed between the LED chips 12r, 12g, and 12b and the condenser lens 18, and the center thereof. The axis and the optical axis are arranged so as to coincide with each other.
A corner cube array (light retroreflector) 52 in which a plurality of pyramid-shaped corner cubes 52a are arranged in a matrix is provided on the surface of the reflection ring 51 on the LED chip 12r, 12g, 12b side. . The corner cube 52a is a combination of a triangular plate having a light reflecting surface and a triangular pyramid shape with the light reflecting surface facing inward. The corner cube 52a can reflect light incident thereon in substantially the same direction as the incident direction of the light.
[0035]
Next, the operation of the lighting devices 50r, 50g, and 50, which are features of the present invention, will be described.
Of the color lights emitted forward from the LED chips 12r, 12g, and 12b and the color lights emitted backward and reflected forward by the base 17, the light incident on the condenser lens 18 is a liquid crystal light valve 31, 32. , 33 so as to be condensed.
[0036]
FIG. 4 is a diagram schematically showing light reflection in the corner cube array.
Each color light propagating in a direction deviating from the condenser lens 18 is incident on the corner cube array 52 of the reflection ring 51. As shown in FIG. 4, each color light incident on the corner cube array 52 is reflected a plurality of times by the light reflecting surface of each corner cube 52a, and is reflected in substantially the same direction as the incident light, that is, toward the LED chips 12r, 12g, and 12b. Is done.
[0037]
According to the above configuration, the corner cube array 52 in which the corner cubes 52a are arranged can reflect each color light incident thereon in substantially the same direction as the incident direction. Therefore, even if the arrangement accuracy of the reflection ring 51 (especially the inclination angle of the light reflection surface with respect to the optical axis) is reduced, the reflection ring 51 can reflect each color light to the LED chips 12r, 12g, and 12b. Therefore, the labor required for disposing the reflective ring 51 can be reduced, and the manufacture of the lighting devices 50r, 50g, and 50b can be facilitated.
[0038]
[Third Embodiment]
Next, a third embodiment of the present invention will be described with reference to FIGS.
The basic configuration of the projection display device of the present embodiment is the same as that of the first embodiment, but the configuration of the illumination device is different from that of the first embodiment. Therefore, in this embodiment, only the periphery of the lighting device will be described with reference to FIGS. 5 and 6, and description of the liquid crystal light valve and the like will be omitted.
FIG. 5 is a schematic diagram illustrating a configuration of the lighting device of the present embodiment.
As shown in FIG. 5, in the lighting devices 60r, 60g, and 60b, a reflection ring (first reflection means) 61 is arranged between the LED chips 12r, 12g, and 12b and the condenser lens 18, and the center thereof is located at the center. The axis and the optical axis are arranged so as to coincide with each other.
On the surface of the reflective ring 61 on the LED chip 12r, 12g, 12b side, a bead aggregate (light retroreflector) 62 in which a plurality of spherical beads 62a are arranged is provided. The beads 62 a are arranged so that half of the beads 62 a are embedded in the reflective ring 61 and the other half protrudes from the reflective ring 61.
[0039]
Next, the operation of the lighting devices 50r, 50g, and 50, which are features of the present invention, will be described.
Of the color lights emitted forward from the LED chips 12r, 12g, and 12b and the color lights emitted backward and reflected forward by the base 17, the light incident on the condenser lens 18 is a liquid crystal light valve 31, 32. , 33 so as to be condensed.
[0040]
FIG. 6 is a diagram schematically showing light reflection in the bead aggregate.
Each color light propagating in a direction deviating from the condenser lens 18 is incident on the bead aggregate 62 of the reflection ring 61. As shown in FIG. 6, each color light incident on each bead 62a is reflected a plurality of times in the bead 62a, and is reflected in substantially the same direction as the incident light, that is, toward the LED chips 12r, 12g, and 12b.
[0041]
According to the above configuration, the bead aggregate 62 in which a plurality of spherical beads 62a that are relatively easy to manufacture can reflect each color light incident thereon in substantially the same direction as the incident direction. Therefore, the production of the reflection ring 61 becomes easier, and the arrangement accuracy of the reflection ring 61 can be reduced, so that the production of the lighting devices 60r, 60g, and 60b can be facilitated.
[0042]
[Fourth Embodiment]
Next, a fourth embodiment of the present invention will be described with reference to FIG.
The basic configuration of the projection display device of the present embodiment is the same as that of the first embodiment, but the configuration of the illumination device is different from that of the first embodiment. Therefore, in this embodiment, only the periphery of the lighting device will be described with reference to FIG. 7, and description of the liquid crystal light valve and the like will be omitted.
FIG. 7 is a schematic diagram illustrating a configuration of the lighting device of the present embodiment.
As shown in FIG. 7, the illumination devices 70r, 70g, and 70b have a reflection ring (first reflection means) 71 disposed between the LED chips 12r, 12g, and 12b and the condenser lens 18, and the center thereof. The axis and the optical axis are arranged so as to coincide with each other. The reflection ring 71 is formed in a spherical shape in which the surface on the LED chip 12r, 12g, 12b side is concave, and this spherical shape allows light incident on the reflection ring 71 to be reflected by the LED chips 12r, 12g, 12b and later. It is arranged in a direction in which the light is reflected by the converging ring (third reflecting means) 72.
[0043]
A light-collecting ring 72 is provided around the LED chips 12r, 12g, and 12b, and is arranged so that the central axis thereof coincides with the optical axis. The condensing ring 72 is formed in an aspherical shape in which the surface on which each color light reflected from the reflecting ring 71 is incident is concave, and this aspherical shape is a condensing lens for all the color light incident thereon. It is formed in a shape that reflects toward 18.
[0044]
Next, the operation of the lighting devices 70r, 70g, and 70b, which are features of the present invention, will be described.
Of the color lights emitted forward from the LED chips 12r, 12g, and 12b and the color lights emitted backward and reflected forward by the base 17, the light incident on the condenser lens 18 is a liquid crystal light valve 31, 32. , 33 so as to be condensed.
The light propagating in a direction deviating from the condenser lens 18 is incident on the reflection ring 71 and is reflected toward the LED chips 12r, 12g, 12b and a condenser ring 72 described later. Part of the reflected light is incident on the LED chips 12r, 12g, and 12b. Light incident on the LED chips 12r, 12g, and 12b is reflected forward as described in the first embodiment. The remaining light enters the condenser ring 72 and is reflected toward the condenser lens 18.
[0045]
According to the above configuration, light that is reflected by the reflecting ring 71 and spills around without being incident on the LED chips 12r, 12g, and 12b is incident on the focusing ring 72 and is reflected forward.
That is, since light spilled around the LED chips 12r, 12g, and 12b can also be used, the ratio of the light emitted from the LED chips 12r, 12g, and 12b and applied to the liquid crystal light valves 31, 32, and 33 can be used. That is, the light use efficiency can be further increased.
[0046]
Further, since the shape of the surface of the condensing ring 72 on which the light is incident is formed on an aspherical surface, almost all of the light spilled around the LED chips 12r, 12g, and 12b is directed to the condensing lens 18. Can be reflected. Therefore, the ratio of the light emitted from the LED chips 12r, 12g, and 12b and applied to the liquid crystal light valves 31, 32, and 33, that is, the light use efficiency can be further increased.
[0047]
[Fifth Embodiment]
Next, a fifth embodiment of the present invention will be described with reference to FIG.
The basic configuration of the projection display device of the present embodiment is the same as that of the first embodiment, but the configuration of the illumination device is different from that of the first embodiment. Therefore, in this embodiment, only the periphery of the illumination device will be described with reference to FIG. 8, and description of the liquid crystal light valve and the like will be omitted.
FIG. 8 is a schematic diagram illustrating a configuration of the lighting device of the present embodiment.
As shown in FIG. 8, the lighting devices 80r, 80g, and 80b are sealed with the LED chips 12r, 12g, and 12b, the lead frame 13p, the lead frame 13q, and the bonding wires 14 by a sealing portion 81 made of resin. Have been.
Protrusions 82 are provided on the liquid crystal light valves 31, 32, and 33 sides of the sealing portion 81, and are arranged such that the central axis and the optical axis coincide. The convex portion 82 is formed in a lens shape such that each color light passing therethrough is condensed on the liquid crystal light valves 31, 32, and 33. On the side surface of the sealing portion 81, a reflection ring 83 is arranged so that its central axis coincides with the optical axis. The reflection ring 83 is formed in an aspherical shape having a concave surface on the side of the LED chips 12r, 12g, 12b, and this aspherical shape allows all the light incident on the reflection ring 83 to reach the LED chips 12r, 12g, It is formed in a shape reflecting on 12b.
[0048]
Next, the operation of the lighting devices 80r, 80g, and 80b, which are features of the present invention, will be described.
Of the color lights emitted forward from the LED chips 12r, 12g, and 12b and the color lights emitted backward and reflected forward by the pedestal portion 17, the light incident on the convex portion 82 is the liquid crystal light valve 31, 32, The light is emitted so as to be converged on 33.
The light that has propagated in the direction deviating from the convex portion 82 enters the reflection ring 83 and is reflected in the direction of the LED chips 12r, 12g, and 12b. The reflected light enters the LED chips 12r, 12g, and 12b, and is reflected forward as described in the first embodiment.
[0049]
According to the above configuration, each component of the lighting devices 80r, 80g, and 80b is provided inside or on the surface of the sealing portion 81. Therefore, even if each component is reduced in size and its strength is reduced, it is supported by the sealing portion 81 and the reduction in strength can be compensated for, so that the lighting devices 80r, 80g, and 80b can be easily reduced in size.
In addition, since the lighting devices 80r, 80g, and 80b can be handled as one component, the number of components handled when manufacturing the projection display device can be reduced, and the manufacturing can be facilitated.
[0050]
Note that the technical scope of the present invention is not limited to the above embodiment, and various changes can be made without departing from the spirit of the present invention.
For example, in the above-described embodiment, the description has been made by adapting the surface of the reflective ring that reflects light to be formed in an aspherical shape. However, the present invention is not limited to the one formed in this aspherical shape. However, the present invention can be applied to other various shapes such as a flat shape.
Further, in the above-described embodiment, the light reflecting surface of the condensing ring has been described as being applied to an aspheric surface, but is limited to the aspheric surface. Without being limited to those formed in a planar shape or a spherical shape, the present invention can be applied to other various shapes.
In this case, it is easy to form the light reflecting surfaces of the reflection ring and the light collection ring, so that less labor is required for processes such as processing and polishing, and it is easy to manufacture the illumination device and the projection display device.
[0051]
Further, in the above embodiment, the illumination device has been described as being applied to a device provided with a condensing lens or a convex portion, but is not limited to a device provided with a condensing lens or a convex portion. The present invention can be applied to a form having no other various light condensing functions, such as a lens having no condensing lens or a convex portion.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing a projection display device according to a first embodiment of the present invention.
FIG. 2 is a schematic diagram showing a lighting device according to the first embodiment of the present invention.
FIG. 3 is a schematic diagram illustrating a lighting device according to a second embodiment of the present invention.
FIG. 4 is a schematic diagram showing light reflection in the corner cube array of FIG. 3;
FIG. 5 is a schematic view showing a lighting device according to a third embodiment of the present invention.
FIG. 6 is a schematic diagram showing light reflection in the bead aggregate of FIG. 5;
FIG. 7 is a schematic diagram illustrating a lighting device according to a fourth embodiment of the present invention.
FIG. 8 is a schematic diagram showing a lighting device according to a fifth embodiment of the present invention.
[Explanation of symbols]
10 Projection display device, 11r, 11g, 11b, 50r, 50g, 50b, 60r, 60g, 60b, 70r, 70g, 70b Illumination device, 12r, 12g, 12b LED chip (light source), 16, 51, 61, 71 Reflection ring (first reflection means), 17 bases (second reflection means), 18 condenser lens, 31, 32, 33 liquid crystal light valve (light modulation means), 41 projection lens (projection means), 52 Corner cube array (light retroreflector), 62a bead aggregate (light retroreflector), 72 light-collecting ring (third reflection means)

Claims (13)

An illumination device used to illuminate an illuminated area, comprising: a light source; and a first reflection unit disposed around a predetermined area in front of the light source,
The lighting device according to claim 1, wherein the first reflecting means reflects light deviating from the predetermined area toward the light source. A second reflecting means is provided behind the light source,
The lighting device according to claim 1, wherein the second reflection unit reflects light reflected by the first reflection unit and propagating backward, toward the front. The first reflection means is formed in an annular shape around the optical axis of light emitted from the light source, and is formed so as to be inclined toward the light source as going outward from the optical axis. ,
The lighting device according to claim 1, wherein a surface that reflects light emitted from the light source is a flat surface. The first reflection means is formed in an annular shape around an optical axis of light emitted from the light source, and a surface reflecting light from the light source is formed as a concave curved surface. The lighting device according to claim 1. The lighting device according to any one of claims 1 to 4, wherein the first reflecting means is made of a light retroreflector. The lighting device according to claim 5, wherein the light retroreflector is a corner cube array in which a plurality of pyramidal corner cubes are arranged. The lighting device according to claim 5, wherein the light retroreflector is a bead aggregate in which a plurality of spherical beads are arranged. The lighting device according to any one of claims 1 to 4, further comprising a third reflection unit provided around the light source to reflect light propagating rearward forward. 9. The lighting device according to claim 8, wherein the third reflecting means is formed in an annular shape around the optical axis, and the light reflecting surface is a flat surface. 9. The lighting device according to claim 8, wherein the third reflecting means is formed in an annular shape around an optical axis, and the light reflecting surface is a concave curved surface. The lighting device according to any one of claims 1 to 10, wherein the light source is a light emitting diode. A condenser lens is provided in the predetermined area,
The illumination device according to claim 1, wherein the light incident on the predetermined region is collected on the illumination target region by the condenser lens. An illumination device including a light source, a light modulation unit that modulates light from the illumination device, and a projection display device including a projection unit that projects light modulated by the light modulation unit,
A projection display device, wherein the lighting device is the lighting device according to claim 1.

Images