JP2001021996A - Illuminating device and projection type video display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an illuminating device capable of guiding light beams emitted from plural light sources on to one irradiation screen, without having to use optical members such as a cylindrical lens and a partial reflection mirror. SOLUTION: Two light sources 1 and 1 for the illuminating device are separately provided with a light emitting part 11 and a parabolic concave mirror 12. An optical path changing member 5 is arranged between the two light sources 1 and 1. The optical part changing member 5 is provided with a reflection surface 51 for a light source 1A and a reflection surface 52 for the light source 1B. Split reflection surfaces 51a to 51c of the reflection surface 51 are arranged in parallel on different planes. Likewise similar result is obtained as to the reflection surface 52. The light reflected by the split reflection surfaces 51a to 51c and 52a to 52c are diffusely projected on to the light incident surface of an integrator lens 3, not overlaying on top of another, but leaving no space between them. Furthermore, the light near the center of the light source 1 is projected near the center of the integrator lens 3, and the peripheral light is projected near the peripheral part of the integrator lens 3.

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 video display using the lighting device.

[0002]

2. Description of the Related Art Heretofore, as a device for displaying a large-screen image, a projection type in which strong light of a lighting device is irradiated on a liquid crystal panel and an image displayed on the liquid crystal panel is enlarged and projected on a screen (not shown). Video display devices are known. Japanese Patent Application Laid-Open No. H11-6979 (IPC: G0) describes an illumination device used in this type of projection type video display device.
2B 27/18). FIG.
FIG. 1 is an explanatory diagram showing a lighting device disclosed in the publication. In this lighting device, by using a plurality of light sources with small inputs, the arc length of each light source is shortened to extend the life and improve the efficiency of light collection, and the light emission stops (lamp burnout) due to the life of the light source. In such a case, the projection can be continued even if it is performed.

[0003] Such an illuminating device will be briefly described with reference to the language of the publication. The light of the first light source 102 passing through the first cylindrical lens 101 and the light of the second light source 104 passing through the second cylindrical lens 103 will be described. Are crossed, the two cylindrical lenses 101 and 103 are arranged at a predetermined angle. In the vicinity of the intersection of the light transmitted through the two cylindrical lenses 101 and 103,
A partial reflecting mirror 105 is provided at a predetermined angle with respect to both lenses. The partial reflecting mirror 105 is a light transmitting part 1 that allows light from one of the cylindrical lenses 101 to pass through.
05a and reflecting portions 105b for reflecting light from the other cylindrical lens 103 are alternately provided in parallel. With such a structure, both cylindrical lenses 101 and 103 are provided.
Transmitted through the common synthetic cylindrical lens 10
6 will be irradiated.

[0004]

However, the above-mentioned conventional illuminating device needs to be provided with the cylindrical lenses 101 and 103 for the light sources 102 and 104, and combines the lights transmitted through the cylindrical lenses 101 and 103. Therefore, the partial reflecting mirror 105 is required,
The number of parts increases. In addition, the manufacturing of the partial reflecting mirror 105 is not easy, so that it becomes expensive. Further, since the arrangement of the cylindrical lenses 101 and 103 and the partial reflecting mirror 105 requires high dimensional accuracy, assembly of the apparatus is not easy.

SUMMARY OF THE INVENTION In view of the above circumstances, the present invention provides an illuminating device and an illuminating device capable of guiding light emitted from a plurality of light sources onto one irradiation surface without using an optical member such as a cylindrical lens or a partial reflecting mirror. It is an object of the present invention to provide a projection type video display device using the same.

[0006]

The lighting device according to the present invention comprises:
A plurality of light sources having a concave reflecting mirror and emitting substantially parallel light,
An optical path changing member that irradiates the entire area of the irradiation surface by having a plurality of reflection surfaces that reflect substantially parallel light emitted by each light source toward a partial region of one irradiation surface. .

In the above configuration, for example, assuming that two light sources are provided, substantially parallel light emitted from one of the light sources is reflected by one reflecting surface of an optical path changing member having two reflecting surfaces, and is irradiated onto the irradiation surface. Similarly, the substantially parallel light emitted from the other light source is reflected by the other reflection surface of the optical path changing member and guided to the other half region of the irradiation surface. As described above, since one irradiation surface is irradiated by using a plurality of light sources, it is possible to achieve a long life and a high efficiency of light collection. Basically, a normal reflecting member may be used as an optical path changing member. Such a normal reflecting member is easy and inexpensive to manufacture, and high-precision mounting work such as when a partial reflecting mirror is provided. Since it is not required, assembly of the device is also facilitated.

[0008] It is preferable that the light incident surface of the integrator lens having a large number of convex lenses be an irradiation surface, and the edge of the reflection surface be positioned corresponding to the valley between the convex lenses of the integrator lens. Here, the edge of the reflection surface hardly contributes to the reflection of light, and when the edge of the reflection surface is located corresponding to the convex lens of the integrator lens, the dark portion due to the edge is widened by the convex lens of the integrator lens. As a result, not only the existence of the convex lens becomes meaningless, but also luminance unevenness may occur. Such a problem can be avoided if the edge of the reflection surface is located corresponding to the valley between the convex lenses of the integrator lens.

A reflecting surface corresponding to each light source is divided into a plurality of portions and arranged on different planes which are parallel to each other. Light from the plurality of light sources is guided alternately on the irradiation surface so as not to overlap with each other. It is preferable that the light near the center is guided near the center of the irradiation surface, and the light near the periphery of each light source is guided near the periphery of the irradiation surface.

Here, for example, substantially parallel light emitted from one of the two light sources is guided to the right half area of the irradiation surface, and substantially parallel light emitted from the other light source is emitted to the left half area of the irradiation surface. If one of the light sources is cut off when the light is guided, even if the above-described integrator lens is used, the light incident on the light source is largely deviated to one side, causing luminance unevenness. With the configuration using the above-mentioned divided reflecting surface, since the light from each light source can be dispersed and radiated to the irradiation surface, such a problem is solved, and the light near the center of the light source is not irradiated to the irradiation surface. Is applied to the vicinity of the center of the image, so that the light use efficiency is also improved.

Two light sources are arranged facing each other,
The reflecting surface or the divided reflecting surface corresponding to the two light sources may be configured by arranging the edges of the two reflecting mirrors in a mountain shape, or two adjacent surfaces of the triangular prism member as mirror surfaces. It may be constituted by doing. The use of the triangular prism member has the advantage that the fabrication of the optical path changing member is simpler and the assembly is easier.

[0012] Further, a projection type video display device of the present invention comprises:
Any of the lighting devices described above, a light valve that modulates light emitted from the lighting device based on a video signal, and a projection lens that enlarges and projects the light modulated by the light valve. Features. Further, in such a projection type video display device, the light from the illumination device is separated into three primary colors and guided to the light valves for each color light, respectively.
The light modulated by the light valve for each color light may be combined and projected.

[0013]

(Embodiment 1) Hereinafter, Embodiment 1 of the present invention will be described with reference to FIGS. 1 and 2. FIG. FIG.
FIG. 2 is an explanatory view showing the lighting device of this embodiment, and FIG.
FIG. 2 is an explanatory diagram showing an example in which two lighting devices of FIG. 1 are combined.

The illuminating device shown in FIG. 1 comprises two light sources 1 and 1 arranged opposite to each other, and an optical path changing member 2 arranged between these two light sources 1 and 1. Each light source 1 includes a light emitting unit 11 composed of a metal halide lamp, etc.
And a parabolic concave mirror 12 for converting the light emitted from the light into substantially parallel light and emitting the light. The optical path changing member 2 corresponds to the positional relationship between each light source 1 and the integrator lens 3 so as to reflect substantially parallel light emitted from each light source 1 toward a partial area of the light incident surface of the integrator lens 3 which is an irradiation surface. It has two reflection surfaces 21 and 22 arranged as follows.

The two light sources 1 and 1 are arranged so that their emission optical axes coincide with each other, and the integrator lens 3 is arranged so that the normal to the light incident surface is perpendicular to the emission optical axis. I have. The reflection surface 21 is arranged at an angle of 45 ° with respect to the emission optical axis of the light source 1A, and guides the emission light of the light source 1A to an upper half region from the center of the integrator lens 3 in the figure. The reflection surface 22 is arranged at an angle of 45 ° with respect to the emission optical axis of the light source 1 </ b> B, and guides the emission light of the light source 1 </ b> B to a lower half region than the center of the integrator lens 3.

The two reflecting surfaces 21 and 22 are obtained by arranging the two reflecting mirrors so as to form a mountain shape. The peaks and skirt ends of the reflection surfaces 21 and 22 are positioned so as to correspond to the valleys between the convex lenses of the integrator lens 3.

The illuminating device shown in FIG. 2 includes two illuminating devices of FIG. 1 (hereinafter referred to as basic illuminating devices), and an optical path changing member 4 is arranged between these two basic illuminating devices.
The two basic illuminators are arranged so that their optical axes after changing the optical path by the optical path changing member 2 coincide with each other, and the integrator lens 3 has a normal to its light incident surface perpendicular to the optical axis after changing the optical path. It is arranged so that it becomes. The reflecting surface 41 of the optical path changing member 4 is composed of the light source 1A and the light source 1B.
Are arranged at an angle of 45 ° with respect to the optical axis after being changed by the light path changing member 2 of the basic lighting device, and the light emitted from the light source 1A is guided to the 1/4 upper end region of the integrator lens 3 in the figure, and the light source 1B Is guided to a quarter region above the center of the integrator lens 3 in the figure. The reflecting surface 42 of the light path changing member 4 is provided on the light path changing member 2 of the basic lighting device including the light sources 1C and 1D.
The light emitted from the light source 1D is guided to the lower end area of the integrator lens 3 in the figure, and the light emitted from the light source 1C is guided to the integrator lens 3 in the figure. It leads to the 1/4 area below the center.

The two reflecting surfaces 41 and 42 are obtained by arranging the two reflecting mirrors so that the edges of the two reflecting mirrors are aligned. The peaks and the skirt ends of the reflecting surfaces 41 and 42 are positioned so as to correspond to the valleys between the convex lenses of the integrator lens 3. Further, the mountain-shaped tops and the ends of the skirts, which are the edges of the reflection surfaces 21 and 22 of the optical path changing member 2, are also positioned so as to correspond to the valleys between the convex lenses of the integrator lens 3.

In the illumination device having the above-described configuration, one irradiation surface (the light incident surface of the integrator lens 3) is irradiated by two or four light sources, so that a long life and a high efficiency of light collection are achieved. be able to. Basically, a normal reflecting member (a flat mirror, a prismatic mirror, a prism) may be used as the optical path changing members 2 and 4. Such a normal reflecting member is easy to manufacture and inexpensive. Since high-precision mounting work such as when preparing is not required,
Assembly of the entire device is also facilitated.

The reflecting surfaces 21 and 22 and the reflecting surface 4
Since the peaks and the ends of the skirts, which are the edges of 1, 42, are positioned so as to correspond to the valleys between the convex lenses of the integrator lens 3, the edges of the reflection surface correspond to the convex lenses of the integrator lens 3. The trouble that occurs when the camera is positioned at a wrong angle can be avoided.

(Embodiment 2) Hereinafter, Embodiment 2 of the present invention will be described with reference to FIGS. FIG. 3 is an explanatory view showing the lighting device of this embodiment, FIG. 4 is a modification of the lighting device of FIG. 3, and FIG. 5 is an explanation showing an example in which two lighting devices of FIG. 3 are combined. FIG. 6 is a configuration diagram of a liquid crystal projector using the illumination device of FIG. 5, and FIG. 7 is an explanatory diagram showing an integrator lens and a polarization conversion member in an enlarged manner.

The illuminating device shown in FIG. 3 comprises two light sources 1, 1 arranged opposite to each other and an optical path changing member 5 arranged between these two light sources 1, 1. Each light source 1 includes a light emitting unit 11 composed of a metal halide lamp, etc.
And a parabolic concave mirror 12 for converting the light emitted from the light into substantially parallel light and emitting the light. The optical path changing member 5 corresponds to the positional relationship between each light source 1 and the integrator lens 3 so as to reflect substantially parallel light emitted from each light source 1 toward a partial area of the light incident surface of the integrator lens 3 which is an irradiation surface. It has reflection surfaces 51 and 52 arranged as follows.

The two light sources 1 and 1 are arranged so that their outgoing optical axes coincide with each other, and the integrator lens 3 is arranged so that the normal to its light incident surface is perpendicular to the outgoing optical axis. I have. The reflection surface 51 is arranged at an angle of 45 ° with respect to the emission optical axis of the light source 1A, and the reflection surface 52 is arranged at an angle of 45 ° with respect to the emission optical axis of the light source 1B.

The reflecting surface 51 is composed of divided reflecting surfaces 51a to 51c. These divided reflecting surfaces 51a to 51c are parallel to each other, but are arranged in different planes shifted in the direction of the emission optical axis of the light source 1. The reflecting surface 52 is a divided reflecting surface 52
a to 52c. These divided reflecting surfaces 52a to 52c
Are parallel to each other, but in different planes shifted in the direction of the emission optical axis of the light source 1, and
It is located corresponding to the separated portion 51c, and the edge of each divided reflecting surface is made to correspond exactly to the edge of the other divided reflecting surface on the optical axis. Thereby, the divided reflection surface 51a
51c and the light reflected by the divided reflecting surfaces 52a-52c do not overlap with each other and have no gap.
Irradiated alternately on the light incident surface of.

Furthermore, since the divided reflecting surfaces 51b and 52b which receive a large amount of light at the central portions of the light sources 1A and 1B are arranged corresponding to the center of the integrator lens 3, light near the centers of the light sources 1A and 1B is provided. Is irradiated near the center of the integrator lens 3, and light near the periphery of the light sources 1A and 1B is irradiated near the periphery of the integrator lens 3.

The reflecting surfaces 51a and 52a, the reflecting surfaces 51b and 5
2b and the reflecting surfaces 51c and 52c are obtained by arranging the edges of two reflecting mirrors in a mountain shape. And
The edges of the peaks and the skirts, which are the edges of each reflection surface, are positioned so as to correspond to the valleys between the convex lenses of the integrator lens 3.

An optical path changing member 5 'in the illumination device of FIG.
Is provided with triangular prism members 53, 54, 55, instead of arranging the edges of two reflecting mirrors in a mountain-shape so that two adjacent surfaces are mirror surfaces. The use of the triangular prism members 53, 54, and 55 has an advantage that it is easier to manufacture and assemble more easily than using the triangular prism members 53, 54, and 55 as compared with the case where the edges of the two reflecting mirrors are arranged in a mountain shape. The method using the triangular prism member can be applied to the lighting device shown in the first embodiment or the lighting device shown in FIG. 5 described below.

The illuminating device shown in FIG. 5 includes two illuminating devices shown in FIG. 3 (hereinafter, referred to as basic illuminating devices), and an optical path changing member 6 is arranged between these two basic illuminating devices.
The two basic illumination devices are arranged so that the optical axes after the optical path change by the optical path changing member 5 coincide with each other, and the integrator lens 3 is such that the normal line of the light incident surface is aligned with the optical axis after the optical path change. It is arranged to be vertical. Then, the reflection surface 61 of the optical path changing member 6 includes the light source 1A and the light source 1
B is disposed at an angle of 45 ° with respect to the optical axis after being changed by the light path changing member 5 of the basic lighting device composed of the light source 1C and the light source 1D. It is arranged at an angle of 45 ° with respect to the optical axis after the change by the changing member 5.

The reflection surface 61 is composed of divided reflection surfaces 61a to 61c. These divided reflecting surfaces 61a to 61c are parallel to each other, but are arranged in different planes shifted in the direction of the emission optical axis of the basic illumination device. The reflection surface 62 includes divided reflection surfaces 62a to 62c. These divided reflecting surfaces 62a-
62c are parallel to each other, but in different planes shifted in the direction of the emission optical axis of the basic illumination device, and are positioned corresponding to the separated portions in the divided reflecting surfaces 61a to 61c, and The edges of the surface correspond exactly to the edges of the other divided reflecting surfaces on the optical axis. Thereby, the divided reflection surfaces 61a to 61c and the divided reflection surfaces 62a to 62c
In the figure, the reflected light is, in order from the upper end of the integrator lens 3, the light of the light source 1A → the light of the light source 1B → the light source 1C.
The light from the light source 1D → the light from the light source 1A is not alternately overlapped and is irradiated onto the light incident surface of the integrator lens 3 without any gap.

Further, the divided reflecting surfaces 61b and 62b which receive a large amount of light at the central portions of the light sources 1A, 1B, 1C and 1D are arranged corresponding to the center of the integrator lens 3, so that the light sources 1A, 1B, Light near the center of 1C and 1D is irradiated near the center of the integrator lens 3,
Light near the periphery of the light sources 1A, 1B, 1C, and 1D is irradiated near the periphery of the integrator lens 3.

The reflecting surfaces 61a and 62a, the reflecting surfaces 61b and 6
2b and the reflecting surfaces 61c and 62c are obtained by arranging the edges of two reflecting mirrors in a mountain shape. And
The edges of the peaks and the skirts, which are the edges of each reflection surface, are positioned so as to correspond to the valleys between the convex lenses of the integrator lens 3. Further, the peak-shaped top and the end of the skirt, which are the edges of the reflection surface of the optical path changing member 5, are also positioned so as to correspond to the valleys between the convex lenses of the integrator lens 3.

In FIG. 5, two syntheses are performed on the four light sources using the optical path polarizing members 5, 5, and 6 in a two-dimensional plane. Y in direction
Axis, the z-axis is taken in the direction perpendicular to the paper surface. For example, the first synthesis is performed from the x-axis direction to the y-axis direction, and the second synthesis is performed with y.
It is also possible to perform the processing three-dimensionally, such as from the axial direction to the z-axis direction. The same applies to the lighting device shown in FIG.

FIG. 6 shows a liquid crystal projector using the illumination device of FIG. The white light emitted from the illumination device is applied to the integrator lens 3, and the light passing through the integrator lens 3 reaches the polarization conversion device 71. The integrator lens 3 is composed of a pair of lens groups, each of which is designed so as to illuminate the entire surface of the liquid crystal panel, which will be described later. Averaging is performed to reduce the difference in light amount between the center and the periphery of the screen.

As shown in FIG. 7, the polarization conversion device 71 is configured by alternately arranging a polarization beam splitter section (hereinafter referred to as a PBS section) 711 and a mirror body 712. The convex lens of the integrator lens 3 faces a basic structural unit including the PBS unit 711 and the mirror body 712. The mirror body 712 is located corresponding to the valley between the convex lenses of the integrator lens 3, a partial light shielding plate 713 is provided on the rear side (the integrator lens 3 side) of the mirror body 712, and the front side (light emission side) of the mirror body 712. ) Is provided with a 1 / 2λ plate 714.

The PBS section 711 includes a polarization separating film 711 a, and allows only the P wave (indicated by a dotted line in the figure) of the light from the integrator lens 3 to pass therethrough, and the S wave to the light emission direction of the integrator lens 3. Is reflected by changing the optical path by 90 °. The mirror body 712 is a PBS unit 711
And a reflection film 712a inclined by 45 ° with respect to the reflected optical axis, and reflects the S wave reflected by the PBS unit 711 in the same direction as the light emission direction of the integrator lens 3. The S wave reflected by the mirror body 712 is transmitted through the 1 / 2λ plate 714, whereby the polarization plane is rotated and converted into a P wave. In this way, all the light passing through the polarization converter 71 is converted into a P-wave. Since the liquid crystal panels 81, 82, and 83, which will be described later, transmit only polarized light corresponding to the alignment direction of the liquid crystal molecules, if the transmitted polarized light is unified into P waves, all light will pass, and the light use efficiency will be improved. improves. The PBS unit 71
If the P wave passing through 1 passes through the 1 / 2λ plate 714, all the light is converted into the S wave.

The light that has been converted into a single polarized light through the polarization conversion device 71 passes through the condenser lens 72 and passes through the total reflection mirror 7.
The light path is changed by 90 ° by 3 to be guided to the first dichroic mirror 74. First dichroic mirror 7
Numeral 4 transmits light in a red wavelength band and reflects light in a cyan (green + blue) wavelength band. First dichroic mirror 7
The light in the red wavelength band that has passed through 4 is reflected by a total reflection mirror 75, guided to a transmissive liquid crystal panel 81 for red light, and transmitted therethrough to be light-modulated. On the other hand, the light in the cyan wavelength band reflected by the first dichroic mirror 74 is guided to the second dichroic mirror 76.

The second dichroic mirror 76 transmits light in the blue wavelength band and reflects light in the green wavelength band. The light in the green wavelength band reflected by the second dichroic mirror 76 is guided to a transmissive liquid crystal panel 82 for green light,
Light is modulated by transmitting the light. Further, the light in the blue wavelength band transmitted through the second dichroic mirror 76 is guided to the transmission type liquid crystal panel 83 for blue light through the total reflection mirrors 77 and 78, and is light-modulated by transmitting the liquid crystal panel 83.

The modulated light (image light of each color) obtained through the liquid crystal panels 81, 82, 83 is applied to a dichroic prism 79.
Are combined into a color image light. The color image light is enlarged and projected by the projection lens 80, and is projected and displayed on a screen (not shown).

Although the liquid crystal projector uses the lighting device of FIG. 5, the liquid crystal projector is constructed by using the lighting device of FIG. 1, the lighting device of FIG. 2, the lighting device of FIG. 3, or the lighting device of FIG. You can also. Here, in the lighting device of FIG. 1 or FIG. 2, since the light from one light source is not dispersed and applied to the integrator lens 3, if one light source is cut off, the light enters the integrator lens 3. Large unevenness occurs in the projected light, and uneven brightness (uneven color) becomes conspicuous in the projected image. On the other hand, in the case of the lighting device of FIG. 3, the lighting device of FIG. 4, or the lighting device of FIG. 5, light from one light source is dispersed and radiated to the integrator lens 3. Since light from another light source that is emitting light is dispersed and emitted from one end of the integrator lens 3 to the other end, luminance unevenness is not so noticeable, and it is possible to continue image projection. It is also possible to deliberately turn off some light sources to set the economy mode. If the composition is three-dimensionally combined, the light is dispersed and emitted in a matrix.

In the example described above, the case where the number of light sources is two or four is shown. However, the number of light sources may be plural, and the number is not limited to these. In FIGS. 3 to 5, the number of divisions of the reflecting surface for each light source or each basic lighting device in the optical path changing members 5, 5 ′, and 6 is set to 3, but is not limited to this number. Further, the number of divisions of the reflection surfaces of the optical path changing member 5 and the optical path changing member 6 in the lighting device of FIG. 5 may be different. The lighting device of the present invention may be used for devices other than the projection type video display device. In FIG. 5, a dichroic prism is used to combine image light of each color as a projection type image display device.
Although a plate-type liquid crystal projector has been described, a configuration in which video light of each color is combined by a dichroic mirror may be used. Also, 3
The invention is not limited to the plate-type liquid crystal projector, but may be a single-plate type liquid crystal projector. Further, a configuration using a light valve other than the liquid crystal panel may be used.

[0041]

As described above, according to the illuminating device of the present invention, one irradiation surface is illuminated by using a plurality of light sources, so that it is possible to extend the life and improve the efficiency of light collection. it can. Basically, a normal reflecting member may be used as an optical path changing member. Such a normal reflecting member is easy and inexpensive to manufacture, and high-precision mounting work such as when a partial reflecting mirror is provided. Since it is not required, the assembly of the entire device is also facilitated. For this reason, the lighting device of the present invention can be manufactured at low cost.

If the light incident surface of the integrator lens having a large number of convex lenses is used as the irradiation surface and the edge of the reflecting surface is positioned corresponding to the valley between the convex lenses of the integrator lens, the convex lens of the convex lens may be used. Practical use is made, and luminance unevenness hardly occurs.

The reflecting surface corresponding to each light source is divided into a plurality of portions and arranged on different planes which are parallel to each other. Light from the plurality of light sources is guided alternately so as not to overlap on the irradiation surface. If the light near the center is guided near the center of the irradiation surface, and the light near the periphery of each light source is guided near the periphery of the irradiation surface, the light from each light source is dispersed and applied to the irradiation surface. Therefore, even when any one of the plurality of light sources is cut off, luminance unevenness can be made less noticeable. In addition, since light near the center of the light source is irradiated near the center of the irradiation surface, light use efficiency is also improved.

With a configuration in which the edges of two reflecting mirrors are aligned in a mountain shape or a configuration in which two adjacent surfaces of a triangular prism member are mirror surfaces, an optical path changing member can be manufactured at a low cost.
Low cost of the lighting device can be realized. Also, the use of the triangular prism member facilitates assembly.

The projection type video display device using the lighting device can be reduced in cost because the lighting device can be realized at low cost. Further, in particular, if it is a projection-type image display device using the illumination device capable of the above-described dispersed irradiation, the color unevenness of the image projected on the screen can be reduced, and
Even if one of the plurality of light sources is cut off, the projection can be continued although the image becomes slightly dark, and the inconvenience of interruption of the projection is eliminated.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram illustrating a lighting device according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a lighting device configured by using two lighting devices of FIG. 1;

FIG. 3 is an explanatory diagram showing a lighting device according to a second embodiment of the present invention.

FIG. 4 is an explanatory view showing a modification of the lighting device of FIG. 3;

FIG. 5 is an explanatory diagram showing a lighting device configured by using two lighting devices of FIG. 3;

FIG. 6 is an explanatory diagram illustrating a liquid crystal projector configured using the lighting device of FIG. 5;

FIG. 7 is an enlarged explanatory view showing a part of an integrator lens and a polarization conversion device in FIG. 6;

FIG. 8 is an explanatory diagram of a conventional lighting device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 light source 11 light emitting section 12 parabolic concave mirror 2 optical path changing member 21 reflecting surface 22 reflecting surface 3 integrator lens (irradiating surface) 4 optical path changing member 41 reflecting surface 42 reflecting surface 5 optical path changing member 51 a to 51 c split reflecting surface 52 a to 52 c split Reflecting surface 6 Optical path changing member 61a to 61c Dividing reflecting surface 62a to 62c Dividing reflecting surface 81 Liquid crystal panel 82 Liquid crystal panel 82 Liquid crystal panel

Continued on the front page F term (reference) 2H088 EA14 EA15 HA13 HA20 HA21 HA24 MA02 MA16 2H091 FA14Z FA17Z FA26Z FA29Z FA41Z FD01 LA11 LA12 MA07

Claims (7)

[Claims] 1. A light source comprising: a plurality of light sources having a concave reflecting mirror for emitting substantially parallel light; and a plurality of reflecting surfaces for reflecting the substantially parallel light emitted by each light source toward a partial area of one irradiation surface. A light path changing member for irradiating the entire area of the irradiation surface with the light source. 2. The lighting device according to claim 1, wherein
A lighting device, wherein a light incident surface of an integrator lens having a number of convex lenses is used as an irradiation surface, and an edge of the reflection surface is positioned corresponding to a valley between the convex lenses of the integrator lens. 3. The lighting device according to claim 1, wherein a reflecting surface corresponding to each light source is divided into a plurality of portions, arranged in different planes parallel to each other, and provided from a plurality of light sources. Light is guided alternately on the irradiation surface so that it does not overlap, light near the center of each light source is guided near the center of the irradiation surface, and light near the periphery of each light source is guided near the periphery of the irradiation surface. A lighting device, comprising: 4. The lighting device according to claim 1, wherein the two light sources are arranged so as to face each other, and the reflection surface or the divided reflection surface corresponding to the two light sources has two reflection surfaces. An illuminating device characterized by being configured by arranging mirrors in a mountain shape with their edges aligned. 5. The lighting device according to claim 1, wherein the two light sources are arranged so as to face each other, and the reflecting surfaces or the divided reflecting surfaces corresponding to the two light sources are arranged on the triangular prism member. An illumination device, wherein two adjacent surfaces are mirror surfaces. 6. A lighting device according to claim 1, a light valve for modulating light emitted from the lighting device based on a video signal, and a light valve modulated by the light valve. A projection type video display device comprising: a projection lens for enlarging and projecting light. 7. The projection type image display device according to claim 6, wherein light from the illumination device is separated into three primary colors, guided to light valves for the respective color lights, and modulated by the light valves for the respective color lights. A projection-type image display device, wherein the projection-type image display device is configured to synthesize and project the combined light.