JP2006337609A - Lighting system and projection type video display apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve high luminance without lowering the efficiency of using light. <P>SOLUTION: The lighting system 10 is constituted of: light source parts 1a and 1b; linearly polarized light generation parts 2a and 2b; a polarized light dependent reflection part 3; a wavelength dependent polarized light rotating part 4; and a rod integrator 5 or the like. The light source part 1a is equipped with a green LED element, and the light source part 1b is equipped with a red LED element and a blue LED element. Light beams from the respective light source parts go through the linearly polarized light generation parts 2, the polarized light dependent reflection part 3, the wavelength dependent polarized light rotating part 4, whereby they are guided to the rod integrator 5, and also converted into linearly polarized light beams having the same or nearly the same polarization direction. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an illumination device and a projection display apparatus.

  As an illuminating device used for a liquid crystal projector or the like, a lighting device such as an ultra-high pressure mercury lamp, a metal halide lamp, a xenon lamp or the like and a parabolic reflector that collimates the irradiation light is generally used. Furthermore, in recent years, it has been attempted to use a light emitting diode (LED) as a light source (see Patent Document 1).

  Some of these illuminating devices have an integration function by a rod integrator in order to reduce unevenness in the amount of light on the irradiated surface. In some lighting apparatuses employing the rod integrator, a light source unit in which three color LED elements are arranged on the same substrate is provided on the incident opening side of the rod integrator in order to further reduce the size of the lighting apparatus.

  FIG. 13 is an explanatory view showing a conventional projection display apparatus 50. The projection display apparatus 50 includes an illumination optical system including a light source unit 51 and a rod integrator 52, and a projection optical system including a liquid crystal display panel 53 and a projection lens 54.

  The light source unit 51 includes a red LED that emits red light, a blue LED that emits blue light, and a green LED that emits green light.

  FIG. 14 is a diagram illustrating a configuration of the light source unit 51. The light source unit 51 includes a substrate 112 and a red LED element 111R, a blue LED element 111B, a green LED element 111G1, a green LED element 111G2, and the like formed on the substrate 112. The reason why two green LED elements are provided in contrast to one red and blue LED elements is that the amount of green light is insufficient.

  The substrate 112 is an insulating substrate. A heat sink 113 is attached to the back surface of the substrate 112, and the heat of the LED elements is radiated from the heat sink 113.

  Referring again to FIG. 13, the light beam emitted from the light source unit 51 and incident on the rod integrator 52 is emitted as a uniform surface light source while repeating total reflection on the side surface of the rod integrator 52.

The light emitted from the rod integrator 52 is projected on a screen (not shown) through a projection optical system including a liquid crystal display panel 53, a projection lens 54, and the like. The light (image light) modulated by passing through the liquid crystal display panel 53 is enlarged and projected by the projection lens 54 and projected and displayed on the screen.
JP-A-10-186507

  However, in the illumination device using the LED element as a light source as described above, there is a problem that the amount of light projected on the screen is insufficient. This is because the LED element emits less light than a light source such as a halogen lamp.

  Therefore, as a method for increasing the brightness, it is first considered to increase the number of LED condensing elements used in the light source unit 51. However, since substantially radial light is emitted from the LED condensing element, it is necessary to enlarge the entrance opening of the rod integrator 52 in order to capture a large amount of light from the many LED condensing elements arranged. However, when the incident aperture of the rod integrator is increased, there is a problem that the light use efficiency of the liquid crystal projector optical system is lowered.

  Accordingly, in view of the above circumstances, the present invention has an object to provide an illumination device that achieves high brightness without reducing light utilization efficiency, particularly in an illumination device that employs an optical integrator such as a rod integrator. .

(Basic configuration of lighting device of the present invention)
The illumination device of the present invention is the same or substantially the same by combining the first light source unit, the second light source unit having a light emission direction different from that of the first light source unit, and the respective color lights from the first and second light source units. Combining means for guiding in the same direction. This lighting device is a so-called two-lamp type lighting device.

  This illumination device is configured such that each color light is always emitted during illumination. Alternatively, each color light is emitted in a time division manner during illumination. Furthermore, you may provide the integration means which equalizes the light radiate | emitted from the said synthetic | combination means on an illumination target object.

(First configuration of lighting device)
In the illumination device according to the present invention, in the basic configuration described above, the combining unit includes a first polarization conversion unit that converts random polarized light from the first light source unit into linearly polarized light having a first polarization direction, and the first polarization unit. A second polarized light converting means for converting random polarized light from the two light source sections into linearly polarized light in the second polarization direction; and one of the emitted lights from the first and second polarized light converting means is reflected. And polarization-dependent reflecting means for guiding the light from the first and second light source units in the same direction or substantially the same direction by transmitting the other. The synthesizing unit may further include a wavelength-dependent polarization rotating unit that converts the polarization direction of the emitted light from the first and second polarization conversion units into the same direction or substantially the same direction. The illumination device having this configuration is hereinafter referred to as a “first configuration illumination device”.

(Second configuration of lighting device)
The lighting device of the present invention may have a second configuration different from the first configuration. In the illumination device of the second configuration, in addition to the basic configuration described above, the synthesizing means reflects wavelength of either one of the emitted light from the first and second light source units and transmits the other. Reflecting means is provided.

(Third configuration of lighting device)
In addition to the basic configuration described above, the illumination device of the third configuration includes a lighting control unit that sequentially lights the first to third color light sources in a time-sharing manner. Time-division reflecting means capable of switching between reflection and transmission, and the time-division reflecting means when the predetermined light source is turned on, the time-division reflecting means is in a reflecting state, and the other predetermined light sources are turned on. Element control means for bringing the means into a transmissive state.

(Configuration of light source)
For example, the illumination device includes at least three light sources of red, blue, and green, and the combining unit can emit white light. At this time, the first light source unit includes a first color light source of the three colors, and the second light source unit includes second and third color light sources of the three colors.

  Further, as to which color is arranged in the first light source unit and which color is arranged in the second light source unit, the light synthesized by the synthesizing unit should be determined to be white light. For example, when the number of light sources is the same, and there is a color component that is insufficient to emit white light, the number of light sources of the color may be increased to compensate for the color component. For example, when the number of light sources that can be arranged in the first light source unit and the number of light sources that can be arranged in the second light source unit are substantially the same, the number of first color light sources is larger than the number of second color and third color light sources. can do. Therefore, in such a case, the light source of the insufficient color component may be arranged in the first light source unit.

  Preferably, the second light source unit includes a plurality of second color light sources and a plurality of third color light sources arranged in a predetermined region, and the second color light source and the third color. At least one of the light sources is arranged point-symmetrically with respect to the center of the predetermined region.

  By arranging each color light source symmetrically, the illuminance of the emitted light of each color from the illumination device can be made more uniform. As a result, the color unevenness of the emitted light by this illuminating device can be reduced.

  Alternatively, the first or second light source unit may further include a fourth color light source. For example, the first light source unit includes a first color light source and a fourth color light source, and the second light source unit includes a second color light source and a third color light source. Alternatively, the first light source unit may include a first color light source, and the second light source unit may include second to fourth color light sources.

  By using the fourth color light source, the color reproducibility of the lighting device can be improved. In addition, the luminance of the illumination light can be improved. When the first to third colors are the three primary colors of red, blue, and green, the fourth color is, for example, yellow.

  Further, when the first light source unit includes a plurality of first color light sources and a plurality of fourth color light sources, each of the first color light source and the fourth color light source includes: You may arrange | position symmetrically with respect to the center of the predetermined area | region in a 1st light source part.

  In addition, the lighting device may further include light sources of fifth and sixth colors such as magenta and cyan. That is, the illumination device according to claims 7 and 8 is not intended to be an illumination device provided with only four color light sources, but intended to be an illumination device provided with light sources having four or more colors.

  Alternatively, the first light source unit includes a first color first wavelength light source that is the first emission wavelength, and a first color second wavelength light source that is a second emission wavelength shorter than the first emission wavelength. , May be provided.

  For example, when the first light source unit includes a 630 nm LED element and a 600 nm LED element, the 630 nm LED element corresponds to an example of a first color first wavelength light source, and the 600 nm LED element This corresponds to an example of a first color second wavelength light source.

  By adopting light sources having a plurality of wavelengths within the same color as described above, the color reproducibility of the lighting device can be improved.

  At this time, the first light source unit includes a plurality of the first color first wavelength light sources and a plurality of the first color second wavelength light sources arranged in a predetermined region. Each of the color first wavelength light source and the first color second wavelength light source may be arranged point-symmetrically with respect to the center of the predetermined region.

  Preferably, the number of light sources arranged in the first light source unit and the total number of light sources arranged in the second light source unit are the same.

  Moreover, the light source of said 1st-4th light source part is a solid light source element, for example.

(Projection-type image display device)
The projection image display device of the present invention, which employs the above-described illumination device configured so that each color light is always emitted during illumination, includes one full-color light valve provided on the emission side of the illumination device, Projection means for projecting image light that has been light-modulated through the full-color light valve.

  A projection image display apparatus according to the present invention, which employs the above-described illumination apparatus configured to emit each color light in a time-division manner during illumination, includes one light valve provided on the emission side of the illumination apparatus. And means for supplying a video signal for each color to the light valve in synchronism with the emission timing of the color light, and a projection means for projecting the video light obtained through the light valve.

  Alternatively, a plurality of illumination devices having the above-described configuration, a light valve provided on the emission side of each illumination device, and means for supplying a video signal for each color to the light valve in synchronization with the emission timing of the color light, A projection-type image display device comprising: color combining means for color-combining light emitted from the light valve; and projection means for projecting image light obtained through the combining means. May be. That is, it may be a two-plate type projection display apparatus using the two-lamp type illumination device of the present invention. Each illumination device in this type of projection display apparatus does not have to emit white light (or emit light).

  According to the present invention, it is possible to provide an illuminating device that achieves high brightness without reducing light utilization efficiency.

  Hereinafter, embodiments of the illumination device of the present invention and a projection display apparatus using the illumination device will be described.

(First embodiment)
FIG. 1 is a diagram illustrating a configuration of the illumination device 10. The illumination device 10 includes light source units 1a and 1b, linearly polarized light generating units 2a and 2b, a polarization dependent reflecting unit 3, a wavelength dependent polarization rotating unit 4, a rod integrator 5, and the like.

  The light source units 1a and 1b are an embodiment of the first and second light source units of the present invention, respectively. The linearly polarized light generators 2a and 2b are embodiments of the first and second polarization conversion means of the present invention, respectively. The polarization dependent reflector 3 is an embodiment of the polarization dependent reflector of the present invention. The wavelength dependent polarization rotation unit 4 is an embodiment of the wavelength dependent polarization rotation means of the present invention. The rod integrator 5 is an embodiment of the integrating means of the present invention.

  The light source unit 1a includes a green LED element, and the light source unit 1b includes a red LED element and a blue LED element. The direction of the principal ray of the emitted light from the light source unit 1a and the direction of the principal ray of the emitted light from the light source unit 1b are vertical or substantially perpendicular. A specific configuration of the light source units 1a and 1b will be described in detail later.

  The linearly polarized light generating unit 2a converts the green random polarized light emitted from the light source unit 1a into linearly polarized light having a predetermined polarization direction (hereinafter referred to as “P-polarized light”). The linearly polarized light generating unit 2b converts red random polarized light and blue polarized light emitted from the light source unit 1b into linearly polarized light having a predetermined polarization direction (hereinafter referred to as “S-polarized light”). The linearly polarized light generating units 2a and 2b are configured by a plurality of polarized beam splitters. The specific configuration of the linearly polarized light generators 2a and 2b will be described in detail later.

  The polarization-dependent reflecting unit 3 transmits the light (P-polarized light) from the linearly polarized light generating unit 2a and reflects the light (S-polarized light) from the linearly polarized light generating unit 2b, so that the linearly polarized light generating units 2a and 2b Are combined and guided in the same direction or substantially the same direction. The polarization-dependent reflection unit 3 is realized by a polarization beam splitter, for example. This polarizing beam splitter transmits the P-polarized light from the linearly polarized light generating unit 2a incident from the first working surface of the polarizing beam splitter, and generates the linearly polarized light incident from the second working surface opposite to the first working surface. The S-polarized light from the part 2b is reflected.

  The wavelength-dependent polarization rotation unit 4 aligns the polarization direction of the light synthesized by the polarization-dependent reflection unit 3 in one direction. As an example, the wavelength-dependent polarization rotation unit 4 is designed so as to act as a half-wave plate for blue light and red light and not as a wave plate for green light. As a result, red light and blue light from the light source unit 1b are converted from S-polarized light to P-polarized light. On the other hand, the green light from the light source unit 1a remains P-polarized light. Thereby, both the lights synthesized by the polarization-dependent reflecting unit 3 become P-polarized light. As described above, an element that selects only an appropriate wavelength region and rotates the polarization axis is well known, and has already been commercialized, for example, under the name “Color Select” by Color Link. (← Referenced to [0141] of JP2003-287818).

  The rod integrator 5 has a quadrangular cylindrical structure (hollow structure) whose inner surface is a mirror surface, or a quadrangular prism structure (glass rod). Alternatively, it may have a shape other than a quadrangular prism, or may have a tapered shape in which the sizes of the entrance opening and the exit opening are different. The light beam from the wavelength-dependent polarization rotation unit 4 incident on the rod integrator 5 is emitted as a uniform surface light source while repeating total reflection on the side surface of the rod integrator 5.

  FIG. 2 is a diagram illustrating a configuration of the light source unit 1a. The light source unit 1a includes a substrate 12a and four green LED elements 11G formed on the substrate 112a. The substrate 12a is an insulating substrate. A heat sink 13a is mounted on the back surface of the substrate 12a, and the heat of the LED elements is radiated from the heat sink 13a.

  FIG. 3 is a diagram illustrating a configuration of the light source unit 1b. The light source unit 1b includes a substrate 12b, two red LED elements 11R and two blue LED elements 11B formed on the substrate 112b.

In the illumination device 10, the number of green LED elements is larger than that of blue LED elements and red LED elements. The reason why the number of light sources is different is that the illumination device 10 can output white light. Green has higher visibility than blue and red, and the luminance (cd / m ² ) needs to be higher than other colors. Therefore, the problem of insufficient luminance may be solved by increasing the number of green LEDs than the number of LEDs of other colors.

  Alternatively, when white light is emitted using LED light sources of three colors having a predetermined spectrum (the light emission amounts of the LED light sources of red, blue, and green are Lr, Lb, and Lg), each color (red When it is known that white light can be generated when the light quantity ratio of Lr ′: Lb ′: Lg ′ is Lr / Lr ′, Lb / Lb ′, and Lg / Lg ′ The number of light sources having the smallest color light may be increased.

  In the example of the light source units 1a and 1b, the color for which the number of light sources is to be increased is arranged in the light source unit 1a, and the other two colors are arranged in the light source unit 1b.

  FIG. 4 is a diagram illustrating a configuration of the linearly polarized light generation unit 2a. The linearly polarized light generating unit 2a includes a polarizing beam splitter array 21 including polarizing beam splitters 21a, 21b, 21c, and 21d, and half-wave plates 22a and 22b disposed on the light output side of the polarizing beam splitters 21b and 21c. And reflecting mirrors 23a and 23b arranged on the light incident side of the polarization beam splitters 21a and 21d.

  When the randomly polarized light enters the polarizing beam splitters 21b and 21c, the P-polarized light passes through the polarizing beam splitters 21b and 21c, respectively.

  On the other hand, the S-polarized light is reflected by the polarization beam splitter 21b or 21c and proceeds in the direction of the polarization beam splitter 21a or 21d. The light traveling to the polarization beam splitters 21a and 21d is reflected. Then, the polarization direction of each light is rotated by 90 degrees by the half-wave plates 22a and 22b to become P-polarized light, which is emitted from the linearly polarized light generating unit 2a, and directed to the polarization-dependent reflecting unit 3. .

  The reason why the reflection mirror 23 is provided on the light incident side of the polarization beam splitters 21a and 21d is to prevent light from the light source unit 1a from directly entering the polarization beam splitters 21a and 21d. This is because, when light from the light source unit 1a directly enters the polarization beam splitters 21a and 21d, S-polarized light is emitted from the linearly polarized light generation unit 2a in the above example.

  Note that the light beam incident side of the polarization beam splitters 21a and 21d need not be limited to the reflection mirror 23 described above, and may be any member that can block light.

  Further, instead of the polarizing beam splitters 21a and 21d, a reflection mirror may be used.

  FIG. 5 is a diagram illustrating a configuration of the linearly polarized light generation unit 2b. In the figure, members having the same functions as those of the linearly polarized light generating unit 2a shown in FIG.

  The P-polarized light transmitted through the polarizing beam splitters 21b and 21c is converted into S-polarized light by the half-wave plate 22c.

  On the other hand, the S-polarized light reflected by the polarization beam splitter 21b or 21c is directed to the polarization-dependent reflecting unit 3 while remaining as S-polarized light.

  FIG. 6 is a diagram showing a projection display apparatus 100 using the illumination device 10. The projection display apparatus 100 includes the illumination device 10 described above, a liquid crystal panel 31, a projection lens 32, and the like.

  The liquid crystal panel 31 has a structure with an RGB color filter or a structure without an RGB color filter. When the liquid crystal panel 31 having the structure including the RGB color filters is used, all LED light sources are turned on simultaneously to guide white light to the liquid crystal panel 31. When the liquid crystal panel 31 having a structure not including the RGB color filter is used, each color LED light source is turned on in a time-division manner for each color sequentially for a predetermined time, and each color is displayed on the liquid crystal panel 31 in synchronization with the lighting timing for the predetermined time. Video signal.

  The light (image light) modulated by transmitting through the liquid crystal panel 31 is enlarged and projected by the projection lens 32 and projected and displayed on a screen (not shown).

  Note that the wavelength-dependent polarization rotation unit 4 described above converts both the light from the light source unit 1a and the light from the light source unit 1b to P-polarized light, but both may be S-polarized light. In this case, the wavelength-dependent polarization rotation unit 4 can be realized by designing it to act as a half-wave plate for green light and not to act as a wave plate for blue light and red light.

  The liquid crystal panel 31 of the projection display apparatus 100 corresponds to one embodiment of the light valve (or full color light valve) of the present invention, but as another embodiment of the light valve of the present invention. May be based on DLP (Digital Light Processing: registered trademark) using DMD (Digital Micromirror Device: registered trademark). In the DMD, it is not necessary to align the polarization direction of incident light in a predetermined direction as in a liquid crystal panel, and therefore the wavelength-dependent polarization rotation unit 4 is not necessary in the illumination device 10.

(Second Embodiment)
FIG. 7 is a diagram illustrating a configuration of the lighting device 20. The illumination device 20 includes light source units 1c and 1d, a wavelength dependent reflection unit 16, a rod integrator 5, and the like.

  The light source unit 1c includes four red LED elements 11R (see FIG. 8), and the light source unit 1d includes two blue LED elements 11B and two green LED elements 11G (see FIG. 9).

  The wavelength dependent reflection unit 16 transmits the red light from the light source unit 1c, reflects the blue light and the green light from the light source unit 1d, and reflects the light from the light source unit 1c and the light from the light source unit 1d. Lead in the same direction or substantially the same direction. The wavelength-dependent reflection unit 16 is realized by, for example, a dichroic mirror.

  A polarization conversion element (not shown) for converting each randomly polarized light into linearly polarized light having the same polarization direction is provided at the subsequent stage (projection optical system side) of the rod integrator 5. Alternatively, the polarization conversion element may be provided before the rod integrator 5.

(Third embodiment)
FIG. 10 is a diagram showing another illumination device 30 of the present invention. The illuminating device 30 includes the light source units 1a and 1b, the time division mirror 17, the rod integrator 5, and the like.

  As with the illumination device 10 of FIG. 1, the light source unit 1a includes four green LED elements, and the light source unit 1b includes two red LED elements and two blue LED elements.

  The time division mirror 17 can switch between reflection and transmission according to the presence or absence of voltage application, and can be configured using, for example, DigiLens (registered trademark) which is a switching diffraction element (Japanese Patent Publication No. 2002-520648). Gazettes (in particular, see paragraphs “0008” and “0009” of the specification) and Japanese Patent Publication No. 2002-525646. The time division mirror 17 is controlled by a mirror control circuit (not shown).

  Each color light source of the light source units 1a and 1b is driven on and off in a time division manner for each color. The time division mirror 17 is switched in synchronism with the on / off drive of each color light source of the light source units 1a and 1b.

  For example, referring to FIG. 10, each color light source is turned on in the order of red → blue → green. When the red LED element of the light source unit 1b is turned on, the time-division mirror 17 reflects the red light and guides it toward the rod integrator 5 (see (a) of the figure). When the blue LED element of the light source unit 1b is lit, the time division mirror 17 reflects the blue light and guides it toward the rod integrator 5 (see FIG. 5A). When the green LED element of the light source unit 1c is lit, the time-division mirror 17 transmits green light and guides it toward the rod integrator 5 (see (a) of the figure).

  That is, the mirror control circuit that controls the time division mirror 17 sets the time division mirror in a reflective state (applying or not applying voltage) when a predetermined light source is turned on, and other predetermined light sources are turned on. Sometimes the time-sharing mirror is in a transmissive state (no voltage application or application).

(Other light source color arrangement examples)
The LED elements arranged in each light source unit are not limited to the above color pattern.

  For example, in the first embodiment, four blue LED elements 11B may be arranged in the light source unit 1a, and two red LED elements 11R and two green LED elements 11G may be arranged in the light source unit 1d. In this case, for example, the wavelength-dependent polarization rotation unit 4 needs to be designed so as to act as a half-wave plate for blue light and not as a wave plate for green light and red light. There is.

  In the above example, four LED elements are arranged (2 × 2 array) in each of the light source units 1a to 1d, but the number is not limited to this. For example, a 3 × 3 array, a 5 × 5 array, a 4 × 3 array, or a polygon array may be used.

  Alternatively, in the second embodiment, four blue LED elements 11B may be arranged in the light source unit 1c, two red LED elements 11B, and two green LED elements 11G may be arranged in the light source unit 1d. At this time, the wavelength-dependent reflection unit 16 transmits the blue light from the light source unit 1c, reflects the green light and the red light from the light source unit 1d, and transmits the light from the light source unit 1c and the light source unit 1d. Are designed to guide light in the same direction or substantially the same direction.

  Alternatively, instead of the light source unit 1c of FIG. 8, a light source unit 1c 'as shown in FIG. 11 may be employed. The light source unit 1c of FIG. 8 includes four red LED elements 11R having the same or substantially the same wavelength. On the other hand, the light source unit 1c 'includes two red LED elements 11R1 having a first wavelength (for example, 600 nm) and two red LED elements 11R2 having a second wavelength (for example, 630 nm). As described above, the color reproducibility of the lighting device can be improved by using two types of LED elements having the same color but slightly different wavelengths. Alternatively, instead of the red LED elements 11R1 and 11R2, the green LED element having the first wavelength and the green LED element having the second wavelength, or the blue LED element having the first wavelength and the blue LED element having the second wavelength, May be provided.

  In addition, the color reproducibility of the illumination device 10 may be improved by employing two types of green LED elements having different wavelengths instead of the light source unit 1a of FIG.

  In addition to the above red, blue, and green, a fourth color solid light source element may be used. For example, by adopting a yellow light source, it is possible to improve the color reproducibility of the lighting device or improve the luminance of the illumination light. Furthermore, the color reproducibility may be further improved by further using solid light source elements of the fifth and sixth colors. For example, a color such as cyan or magenta may be used as the light source. Alternatively, cyan, magenta, etc. may be used as the fourth color light source instead of yellow.

(Projection-type image display device with multiple lighting devices)
FIG. 12 is a diagram showing a projection display apparatus 200 using a plurality of illumination devices. The projection display apparatus 200 includes a plurality of illumination devices 40 (40a and 40b), liquid crystal panels 41 and 42, a combining unit 43, a projection lens 44, and the like.

  The configuration of the illumination device 40 (40a, 40b) is substantially the same as the configuration of the illumination device 40 described above. However, the illumination devices 40a and 40b are provided with light sources of different colors, and are different in that white light is not emitted like the illumination device 10a. For example, the illumination device 40a includes red and yellow light sources, and the illumination device 40b includes blue and green light sources. The light emitted from the illumination device 40a is modulated by passing through the liquid crystal panel 41. The liquid crystal panel 41 is supplied with red and yellow video signals from a liquid crystal display panel driver (not shown). The light emitted from the illumination device 40b is modulated by passing through the liquid crystal panel 42. Blue and green video signals are supplied to the liquid crystal panel 42 from a liquid crystal display panel driver (not shown). The light modulated by the liquid crystal panel 41 and the light modulated by the liquid crystal panel 42 are combined by the combining means 43, enlarged and projected by the projection lens 44, and projected and displayed on a screen (not shown).

  The synthesizing unit 43 includes a polarization beam splitter, a dichroic mirror, or the like. When the combining means 43 is a polarization beam splitter, the illumination device 40 and the liquid crystal panels 41 and 42 are designed so that light transmitted through the liquid crystal panel 41 is P-polarized light and light transmitted through the liquid crystal panel 42 is S-polarized light. . When the combining means 43 is a dichroic mirror, the dichroic mirror is designed to transmit red and yellow and reflect blue and green.

  Alternatively, in the projection display apparatus 200, the illumination device 10 that emits white light may be used instead of the illumination device 40. In this case, a polarization beam splitter is used as the combining means 43.

  In the above description, the light modulation means (the liquid crystal panel 41 and the liquid crystal panel 42) are arranged in the previous stage of the synthesizing means 43. However, the light modulation means may be arranged in the subsequent stage of the synthesizing means 43. For example, one liquid crystal panel may be disposed between the combining unit 43 and the projection lens 44. In this case, red, yellow, blue, and green video signals are supplied to the liquid crystal panel from a liquid crystal display panel driver (not shown).

  Also in the projection display apparatus 200 described above, a DLP may be used for the light valve instead of the liquid crystal panel.

  It should be considered that the embodiments and experimental examples disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and is intended to include meanings equivalent to the scope of claims for patent and all modifications within the scope.

  For example, in the above embodiment, each LED element has been described as being disposed on the same substrate, but may be disposed on a separate substrate.

  In the above description, the rod integrator is described as an example of the “optical integrator” of the present invention. However, the optical integrator may be a fly-eye lens (group).

  In the above description, the LED element is described as an example of the “light source” of the present invention, but a solid light source element other than the LED element may be used. Alternatively, a small light source other than the solid light source element may be used.

1 is a diagram illustrating a configuration of a lighting device 10. FIG. It is a figure which shows the structure of the light source part 1a. It is a figure which shows the structure of the light source part 1b. It is a figure which shows the structure of the linearly polarized light production | generation part 2a. It is a figure which shows the structure of the linearly polarized light production | generation part 2b. 1 is a diagram showing a projection display apparatus 100 using an illumination device 10. FIG. It is a figure which shows the structure of the illuminating device 20. FIG. It is a figure which shows the structure of the light source part 1c. It is a figure which shows the structure of the light source part 1d. It is a figure which shows the illuminating device 30. FIG. It is a figure which shows the structure of light source part 1c '. It is a figure which shows the projection type video display apparatus 200 using several illuminating devices. It is explanatory drawing which showed the conventional projection type video display apparatus. It is a figure which shows the structure of the light source part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1a, 1b Light source part 2a, 2b Linearly polarized light production | generation part 3 Polarization dependence reflection part 4 Wavelength dependence polarization conversion part 5 Rod integrator 10 Illumination device 11R Red LED element 11G Green LED element 11B Blue LED element 21 Polarizing beam splitter array 21a, 21b, 21c, 21d Polarizing beam splitter 22 Half-wave plate 100 Projection-type image display device

Claims (21)

A lighting device including light sources of at least three colors of red, blue, and green,
A first light source unit comprising a first color light source of the three colors;
Of the three colors, a second light source unit including second and third color light sources, and a light emitting direction different from the first light source unit;
And a combining unit that combines the respective color lights from the first and second light source units and guides them in the same or substantially the same direction.
The number of color light sources arranged in the first and second light source units is set so that the combining unit can generate white light by combining the color lights from the first and second light source units. Item 2. The lighting device according to Item 1.
The synthesis means includes
First polarization conversion means for converting randomly polarized light from the first light source unit into linearly polarized light in a first polarization direction;
Second polarization conversion means for converting randomly polarized light from the second light source unit into linearly polarized light in a second polarization direction;
By reflecting one of the polarized light emitted from the first and second polarization conversion means and transmitting the other, the light from the first and second light source units is directed in the same direction or substantially in the same direction. The lighting device according to claim 1, further comprising a polarization-dependent reflecting means for guiding the light.
The illuminating device according to claim 3, further comprising wavelength-dependent polarization rotation means for converting the polarization direction of the light emitted from the first and second polarization conversion means into the same direction or substantially the same direction.
The synthesis means includes
The illumination device according to claim 1, further comprising wavelength-dependent reflection means that reflects either one of the light emitted from the first and second light source units and transmits the other.
The second light source unit is
A plurality of second color light sources and a plurality of third color light sources are arranged in a predetermined area,
6. The device according to claim 1, wherein at least one of the second color light source and the third color light source is arranged in point symmetry with respect to the center of the predetermined region. Lighting equipment.
The illuminating device according to claim 1, further comprising a fourth color light source in either the first or second light source unit.
The first light source unit further includes a fourth color light source,
The first light source unit includes a plurality of first color light sources and a plurality of fourth color light sources arranged in a predetermined area.
7. The device according to claim 1, wherein at least one of the first color light source and the fourth color light source is arranged in point symmetry with respect to the center of the predetermined region. Lighting equipment.
The first light source unit is
A first color first wavelength light source that is the first emission wavelength;
The lighting device according to claim 1, further comprising: a first color second wavelength light source having a second emission wavelength shorter than the first emission wavelength.
The first light source unit is
A plurality of the first color first wavelength light sources and a plurality of the first color second wavelength light sources are arranged in a predetermined region,
The lighting device according to claim 9, wherein at least one of the first color first wavelength light source and the first color second wavelength light source is arranged symmetrically with respect to the center of the predetermined region. .
A first light source unit;
A second light source unit having a light emission direction different from that of the first light source unit;
And combining means for combining the respective color lights from the first and second light source sections and guiding them in the same or substantially the same direction,
The synthesis means includes
First polarization conversion means for converting randomly polarized light from the first light source unit into linearly polarized light in a first polarization direction;
Second polarization conversion means for converting randomly polarized light from the second light source unit into linearly polarized light in a second polarization direction;
By reflecting one of the polarized light emitted from the first and second polarization conversion means and transmitting the other, the light from the first and second light source units is directed in the same direction or substantially in the same direction. An illumination device comprising a polarization-dependent reflecting means for guiding.
The illuminating device according to claim 11, further comprising wavelength-dependent polarization rotation means for converting the polarization direction of the light emitted from the first and second polarization conversion means into the same direction or substantially the same direction.
The illumination device according to any one of claims 1 to 12, further comprising an integration unit that uniformizes light emitted from the synthesis unit on an illumination target.
The lighting device according to claim 1, wherein the number of light sources arranged in the first light source unit and the total number of light sources arranged in the second light source unit are the same. .
The lighting device according to claim 1, wherein the light source is a solid light source element.
A lighting control means for sequentially lighting the first to third color light sources in a time-sharing manner;
The synthesis means includes
Time-division reflecting means capable of switching between reflection and transmission according to the presence or absence of voltage application;
Element control means for setting the time-division reflecting means in a reflective state when a predetermined light source is turned on, and for making the time-division reflecting means in a transmissive state when another predetermined light source is turned on. The lighting device according to any one of claims 1 to 15.
The lighting device according to any one of claims 1 to 15, wherein each color light is always emitted during illumination.
The illumination device according to any one of claims 1 to 16, wherein each color light is emitted in a time division manner during illumination.
An illumination device according to claim 17;
One full-color light bulb provided on the exit side of the illumination device;
A projection type image display apparatus comprising: projection means for projecting image light that is light-modulated through the full-color light valve.
The lighting device according to claim 18;
One light valve provided on the exit side of the illumination device;
Means for supplying a video signal for each color to the light valve in synchronization with the emission timing of the color light;
And a projection means for projecting image light obtained by passing through the light valve.
A plurality of lighting devices according to claim 17 or 18,
A light valve provided on the exit side of each lighting device;
Means for supplying a video signal for each color to the light valve in synchronization with the emission timing of the color light;
Color synthesizing means for color synthesizing light emitted from the light valve;
And a projection means for projecting image light obtained by passing through the synthesizing means.

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