JP5146566B2 - Projection apparatus and projector - Google Patents

Description

  The present invention relates to an image projection apparatus and a projector that project an image.

  Conventionally, a projector light source that magnifies and displays a color image is a discharge lamp that has a wide emission spectrum band and a high light emission output, such as an ultra-high pressure mercury lamp. By switching the color filter in a time division manner, only a predetermined wavelength is extracted from the emission spectrum of the discharge lamp, or a wavelength region having components of each color by optical components that can be selected as in Patent Document 2. The light of each color light was generated by extracting only the light of.

JP 2000-227782 A Japanese Patent Laid-Open No. 10-171045

  However, in the conventional method, the wavelength region to be extracted and used in the emission spectrum emitted from the light source is limited to the band in which the color light flux is generated. Therefore, the light in the unused region is wasted and the light source is efficiently used. Could not be used. Furthermore, since the light source emits light in the unused area together, it is necessary to emit light with high output to obtain high-luminance color light. On the other hand, the light energy in the unused area depends on each optical component. Therefore, it is necessary to constantly cool the periphery of the light source and each optical component.

In order to solve the above-described problems, a projection apparatus according to the present invention includes a light source device that emits a light beam, a light modulation device that modulates the incident light beam according to image information to form an optical image, and the optical image. A projection optical system that projects a plurality of light sources that emit light of different colors, and alternately guides the light source that emits the luminous flux from the plurality of light sources to a predetermined position. The color information switching unit that switches the color light of the luminous flux, the light emission control unit that causes the one of the guided light sources to emit light and the other light source to extinguish, and the image information according to the switched color light And an image information generation unit for generating the image information.
According to the present invention, since the light source that emits the light flux is alternately switched from among the plurality of light sources, it is possible to emit only the light source that emits the light flux and to quench the light source that does not emit the light flux. Since power is concentratedly supplied to the emitted light source, high-luminance light emission is possible and the light source can be used efficiently. Furthermore, since light emission in an unnecessary band is suppressed, heat generation due to unnecessary light can be suppressed.

  In the present invention, the color light switching unit may include a linear guide unit that sequentially guides the light source to a predetermined position by reciprocating movement, and a rotation guide that sequentially guides the light source to a predetermined position by a circular operation. A part may be provided.

In the present invention, it is preferable that the predetermined position is substantially on the optical axis on the incident side of the light modulation device.
According to the present invention, since the light source that emits light is moved on the optical axis on the incident side of the light modulation device, the light source does not match the optical axis of the light modulation device with an optical component or the like. Can be incident on the light modulation device, so that optical components can be reduced.

In the present invention, it is preferable that the plurality of light sources emit at least red color light, green color light, and blue color light.
According to the present invention, a color image with three primary colors can be projected.

  In the present invention, the light source is preferably a semiconductor light emitting element, and the semiconductor light emitting element may be a semiconductor light emitting diode or a semiconductor laser.

In the present invention, the light source preferably includes a light guide that guides incident light to a predetermined region and emits the light.
According to the present invention, it is possible to efficiently irradiate by limiting a region without diverging light emitted from a light source.

In the present invention, it is preferable that the color light switching unit switches the color light that irradiates the light beam according to a timing defined according to the color light, and the time during which the light beam of the green color light is irradiated It is preferable that each time is longer than each time when irradiation is performed.
According to the present invention, it is possible to adjust the color balance according to the characteristics of the human eye.
By applying the above-described projection apparatus to a projector, it is possible to cope with low power consumption and miniaturization.

1 is a diagram illustrating a schematic configuration of a projector according to a first embodiment of the invention. 5 is a timing chart for switching light sources according to the first embodiment of the present invention. FIG. 6 is a diagram illustrating a schematic configuration of a projector according to a second embodiment of the invention. The side view and front view of a rotation guide part and a light source part which concern on Embodiment 2 of this invention. The timing chart which switches the light source which concerns on Embodiment 2 of this invention.

Hereinafter, embodiments of the present invention will be described using a projector including a projection apparatus.
(Embodiment 1)

<Overall configuration>
FIG. 1 is a diagram showing a schematic configuration of a projector 1 as Embodiment 1 of the invention. The projector 1 includes a light source device 10, a color light switching unit 20, a light modulation device 30, an image information generation unit 40, an image signal processing unit 50, a light emission control unit 60, a light emission power supply unit 65, a projection. And an optical system 70. Among these, the light source device 10 includes a light source unit 80 and a uniform illumination optical system 15 and emits parallel light beams. The color light switching unit 20 includes a linear guide unit 90, a displacement magnifying unit 92, and a light source selection unit 25, and switches the color light of the light beam emitted from the light source device 10.

  The light source unit 80 includes light sources of three primary colors, that is, a light source (R) 82 that emits red color light, a light source (G) 84 that emits green color light, and a light source (B) 86 that emits blue color light. These light sources 82 to 86 are constituted by semiconductor light emitting elements, specifically, semiconductor light emitting diodes 110 (FIG. 4) that emit light of each color. Further, each of the light sources 82 to 86 is provided with the reflecting mirror 115 (FIG. 4), so that the light emitted from the light sources 82 to 86 is radiated to one side. Further, the light source unit 80 is connected to the linear guide unit 90 via a displacement enlarging unit 92. The semiconductor light-emitting element is not limited to the single-color semiconductor light-emitting diode 110, and a semiconductor light-emitting diode (3 in 1 chip LED) formed by integrating three primary colors can also be used. Furthermore, it is not limited to a semiconductor light emitting diode, for example, a semiconductor laser can be adopted, and these may be mixed.

  Although not shown in the figure, the uniform illumination optical system 15 converts the incident light into a substantially uniform light beam having a substantially uniform intensity distribution and emits it, for example, by a fly-eye lens. Further, the optical axes of the uniform illumination optical system 15 and the light modulation device 30 are arranged so as to substantially coincide with each other, and the light beam of the light source (G) 84 moved on the optical axis is parallel to the uniform illumination optical system 15. After being emitted, the light enters the light modulation device 30.

  The light source selection unit 25 selects a light source that emits colored light at every predetermined timing from among the light sources 82 to 86 of the light source device 10, and generates an electrical signal corresponding to the selected light source. The data is sent to the control unit 60 and the image information generation unit 40. The timing for selecting the light source and the electrical signal will be described later.

  The linear guide unit 90 is configured by, for example, an actuator using a piezo element (PZT), and moves in a linear direction in accordance with an electrical signal from the light source selection unit 25. Note that three stop positions can be set by laminating the piezo elements in two layers and selecting a piezo element to be driven from the two layers. In addition, a displacement enlarging unit 92 and the light source unit 80 described above are added to the linear guide unit 90 via the displacement enlarging unit 92. The displacement magnifying unit 92 has a function of mechanically magnifying the movement amount, that is, the displacement of the linear guide unit 90 based on the principle of “leverage” (details of the displacement magnifying unit are disclosed in, for example, JP-A-2005-86881). Issue publicity). With such a configuration, the linear guide unit 90 can move any one of the light sources 82 to 86 on the optical axis of the uniform illumination optical system 15 in accordance with an instruction from the light source selection unit 25.

  In response to the electrical signal from the light source selection unit 25, the light emission control unit 60 causes the light source that emits colored light to emit light and extinguishes other light sources. Specifically, the power from the light emission power supply unit 65 is supplied only to the light source that emits light.

  The image signal processing unit 50 converts the image signal input from the image input terminal 55 into a digital image signal that can be separated into red, green, and blue image signals by AD conversion processing. The converted digital image signal is sent to the image information generation unit 40.

  The image information generation unit 40 extracts an image signal corresponding to the color of the light source selected by the light source selection unit 25 from the digital image signal sent from the image signal processing unit 50, and is configured by a binary signal. Image information is generated and sent to the light modulation device 30.

  Although not specifically shown, the light modulation device 30 includes a transmissive liquid crystal panel (light valve) inside, and an image generated by the image information generation unit 40 using the light beam incident from the uniform illumination optical system 15. An optical image is formed by modulation according to information. Here, since the incident light flux is the color light of the selected light source, and the image information is an image signal corresponding to the color of the selected light source, the formed optical image is the input image signal. Is an image obtained by color-separating the selected image with the color of the selected light source.

  The projection optical system 70 enlarges and projects the optical image formed by the light modulation device 30 to form a large screen image on the screen 75. That is, on the screen 75, a monochromatic image based on the color of the light source selected by the light source selection unit 25 is always displayed.

  The projector 1 includes electronic devices such as a CPU, a RAM, and a ROM (not shown) as hardware resources. The CPU reads various programs and data such as a basic control program stored in the ROM, develops and executes these various programs and data in a main memory area provided in the RAM, and controls each unit included in the projector 1. Running. Further, the light source selection unit 25, the light emission control unit 60, the image signal processing unit 50, and the image information generation unit 40 are configured such that these hardware resources and various software stored in a RAM, a ROM, and the like are organically combined. Each function is realized by collaborating.

<Operation of color light switching unit>
Next, the light source switching operation by the color light switching unit 20 will be described with reference to FIG. FIG. 2 is a timing chart for explaining the timing of switching the light source. This timing chart shows the clock output (CLK), the light emission timings of the light sources 82 to 86, the driving timing of the piezo elements, and the color and intensity of the light beam emitted from the light source unit 80 from the top with the horizontal axis as the time axis. . In the first embodiment, the light source switching operation is performed based on the clock output of the clock built in the CPU.

  Here, for example, as shown in FIG. 1, the light sources 82 to 86 of the light source unit 80 are stacked in the order of the light source (B) 86, the light source (G) 84, and the light source (R) 82 from the bottom. ) 84 is selected by the light source selection unit 25, using the predetermined clock output as a trigger, the light source selection unit 25 sends a predetermined signal to the linear guide unit 90 in order to move the light source unit 80 downward. Send to. In response to this signal, the linear guide unit 90 sends a pulse (PZT drive pulse) for moving in one direction to the piezo actuator, and the light source unit 80 moves downward. As a result, the light source (R) 82 is disposed on the optical axis of the uniform illumination optical system 15. In addition, the light source selection unit 25 sends a predetermined signal to the light emission control unit 60 in order to turn on the light source (R) 82. Upon receiving this signal, the light emission control unit 60 sends the power from the light emission power supply unit 65 only to the light source (R) 82. As a result, the light source device 10 emits a red light beam. Therefore, a red image is projected on the screen 75 by the functions of the image information generation unit 40 and the light modulation device 30 described above, and this state is continued for a predetermined time (T1).

  Subsequently, upon receiving a clock output indicating the passage of a predetermined time (T1), the linear guide unit 90 generates a pulse to be moved in the other direction and sends it to the piezo actuator, and the light source unit 80 moves upward, A light source (G) 84 is disposed on the optical axis of the uniform illumination optical system 15. The light emission control unit 60 stops the power supply to the light source (R) 82 and sends the power from the light emission power supply unit 65 only to the light source (G) 84. In addition, the emission intensity of the light beam decreases until the color light beam emitted from the light source device 10 is completely switched. Using this short time, the image information generation unit 40 rewrites the display on the liquid crystal panel of the light modulation device 30. As a result, a green image is projected on the screen 75, and this state is continued for a predetermined time (T2).

  Similarly, a blue image is projected on the screen 75 for a predetermined time (T3), and a green image is again projected on the screen 75 for a predetermined time (T4), completing one cycle (T0). .

  In this way, by sequentially switching the image on the screen 75 in red, green, blue, green, red, green,... Within 20 μs, the viewer of the screen 75 can It is known that monochromatic images projected in division can be combined and recognized as a color image.

Each predetermined time in one cycle (T0) has the following relationship.
(T2 + T4)> T1 = T3

  That is, the time (T1) when the red light beam is emitted is equal to the time (T3) when the blue light beam is emitted, and these are shorter than the time (T2 + T4) when the green light beam is emitted. As a result, since the green single-color image that is difficult to be seen by human eyes is displayed for a longer time than the other single-color images, the projector 1 displays a bright color image in which the three primary colors of red, green, and blue are harmonized. it can. In addition, since the projector 1 uses the semiconductor light emitting diode 110 as a light source and emits light of a required color for a required time, the projector 1 does not require a cooling unit and can be held and projected by a hand. Suitable for portable projectors.

(Embodiment 2)
Next, Embodiment 2 of the present invention will be described with reference to FIG. In the following description, the same parts as those already described are denoted by the same reference numerals and the description thereof is omitted or simplified. FIG. 3 is a diagram showing a schematic configuration of the projector 1 according to the second embodiment. In Embodiment 1 described above, the light source selected by the light source selection unit 25 is guided onto the optical axis of the uniform illumination optical system 15 by moving the light source unit 80 in the uniaxial linear direction by the linear guide unit 90.

  On the other hand, in the second embodiment, by adopting a rotation guide part 95 that is one form of a rotation guide part that rotates and guides the light source part 80, the light source part 80 is rotated in one direction. The light source selected by the light source selection unit 25 is guided on the optical axis of the uniform illumination optical system 15.

  FIG. 4 is a side view and a front view of the rotation guide unit 95 and the light source unit 80. The rotation guide unit 95 includes a pulse motor 100. The light source unit 80 includes a rotating housing 88, a light guide 120, semiconductor light emitting diodes 110 for each color, and a reflecting mirror 115 corresponding to each semiconductor light emitting diode 110.

  The rotary casing 88 has one side in the rotation axis direction connected to the end of the rotation shaft 105 of the pulse motor 100, and the other side in the rotation axis direction has a semiconductor light emitting diode 110 as a light source and a reflecting mirror. 115 are arranged at equal intervals on the locus 140 of the optical axis of the uniform illumination optical system 15 when rotated. The light sources are separated by partition plates (130A, 130B, 130C) so as to limit the emission area of the light sources, and a transparent plate 125 is provided on the surface of the rotary casing 88 on the side where light is emitted. It is glued. On the light source side of the transparent plate 125, a light guide 120 that emits light incident on the conical entrance at a predetermined intensity only in a predetermined region is opposed to each light source. Has been.

  The light emitted from the semiconductor light emitting diode 110 by the light guide 120 and radiated toward the light guide 120 by the reflecting mirror 115 is incident on the light guide 120, and the optical axis locus 140 described above. From the emission part of the light guide 120 adhered along, the light is emitted as a band of light having a uniform intensity distribution. The emission areas of the respective colors are not uniform, and the emission areas of the green light sources are arranged to be wider than the emission areas of the other light sources. Specifically, the angles indicating the red and blue emission areas are each 100 degrees, whereas the angle indicating the green emission area is 160 degrees. As a method of supplying power to the semiconductor light emitting diode 110 rotated by the rotation guide unit 95, for example, a wireless power feeding method by electromagnetic induction can be adopted.

  FIG. 5 is a timing chart for explaining the timing of switching the light source in the second embodiment. This timing chart shows the light emission timings of the light sources 82 to 86 and the color and intensity of the light beam emitted from the light source unit 80 from above with the horizontal axis as the rotation angle of the pulse motor 100. In the second embodiment, the light source switching operation is performed based on the rotation angle of the pulse motor 100.

  Here, for example, as shown in FIG. 3, when the light source (B) 86 is selected by the light source selection unit 25, the light source selection unit 25 uses the rotating housing of the light source unit 80 as a trigger. A predetermined signal is sent to the rotation guide unit 95 in order to move the body 88 clockwise (θ direction). Upon receiving this signal, the rotation guide unit 95 generates a pulse to be moved in the clockwise direction and sends it to the pulse motor 100, and the light source unit 80 rotates in the clockwise direction at a predetermined rotation speed. As a result, the state in which the optical axis of the uniform illumination optical system 15 is on the partition plate 130A is set as the origin (0 degree), that is, the starting point. Thereafter, the light emission control unit 60 supplies power to only the light source (R) 82. Therefore, red light from the light source (R) 82 enters the uniform illumination optical system 15. As a result, the light source device 10 emits a red light beam. Therefore, a red image is projected on the screen 75 by the functions of the image information generation unit 40 and the light modulation device 30, and this state is continued for a predetermined time (Tr).

  Next, immediately before a predetermined time (Tr) elapses, the light emission control unit 60 supplies power to the light source (G) 84 that is the next light source. Immediately after the predetermined time (Tr) is exceeded, the rotation angle of the light source unit 80 exceeds 100 degrees. Thereafter, the green light from the light source (G) 84 enters the uniform illumination optical system 15 for the predetermined time (Tg). Incident on the surface. The supply of power to the light source (R) 82 is paused immediately after the rotation angle of the light source unit 80 exceeds 100 degrees. In this way, the image on the screen 75 is successively and sequentially switched to red, green, blue, red, green, blue,... Within 20 μsec. The viewer can recognize the image as a color image.

As mentioned above, although this invention was demonstrated based on embodiment shown in figure, this invention is not limited to this Embodiment 1 and 2, The modification as described below can also be assumed.
(1) The light modulation device 30 is not limited to a transmissive light valve, and may be a method using LCOS (Liquid Crystal On Silicon) which is a reflective liquid crystal element, or a DMD using a micromirror. A modulation method using (Digital Micromirror Device) may be used.
(2) The light source unit 80 is not limited to red, blue, and green light sources, and may further include a light source that emits other color light such as white.

  DESCRIPTION OF SYMBOLS 1 ... Projector, 10 ... Light source device, 15 ... Uniform illumination optical system, 20 ... Color light switching part, 25 ... Light source selection part, 30 ... Light modulation apparatus, 40 ... Image information generation part, 50 ... Image signal processing part, 55 ... Image input terminal 60 ... Light emission control part 65 ... Light emission power supply part 70 ... Projection optical system 75 ... Screen 80 ... Light source part 82-86 Light source 88 ... Rotary casing 90 ... Linear guide part 92 ... Displacement expansion part, 95 ... Rotation guide part, 100 ... Pulse motor, 105 ... Rotating shaft, 110 ... Semiconductor light emitting diode, 115 ... Reflector, 120 ... Light guide, 125 ... Transparent plate, 130 ... Partition plate, 140 ... trajectory of the optical axis.

Claims (11)

A light source device that emits a light beam, a color light switching unit that switches color light of the light beam, a light modulation device that modulates the incident light beam according to image information to form an optical image, and projection optics that projects the optical image With the system,
The light source device
A plurality of light sources emitting different colored lights,
A plurality of light guides provided corresponding to each of the plurality of light sources and guiding the light emitted from the light sources and emitting from the emission region,
The color light switching unit is
A rotation guide unit for rotating the light source unit to sequentially guide the emission region corresponding to the plurality of light sources to a predetermined position for emitting a light beam from the light source device;
A light emission control unit for causing the light source corresponding to the guided emission region to emit light and for quenching other light sources;
An image information generation unit that generates the image information according to the switched color light ,
The plurality of light sources are arranged at regular intervals on a locus of the predetermined position when a cyclic operation is performed by the color light switching unit,
The emission regions of the plurality of light guides are arranged so that the emission region corresponding to the light source of a predetermined color is a light source of another color on the locus of the predetermined position when the cyclic operation by the color light switching unit is performed. A projection apparatus, wherein the projection apparatus is arranged so as to be wider than a corresponding emission area . The projection device according to claim 1,
The projection apparatus , wherein the light guide is configured to emit incident light from the emission region with uniform intensity . The projection apparatus according to claim 1 or 2 ,
The light source device includes a uniform illumination optical system, and light emitted from the light guide is incident on the uniform illumination optical system, and light emitted from the uniform illumination optical system is emitted from the light source device. Projection device. The projection apparatus according to any one of claims 1 to 3,
The projection apparatus characterized in that the predetermined position is substantially on the optical axis on the incident side of the light modulation device. In the projection device according to any one of claims 1 to 4,
The projection device, wherein the plurality of light sources emit at least red color light, green color light, and blue color light. The projection apparatus according to any one of claims 1 to 5,
The projection apparatus, wherein the light source is a semiconductor light emitting element. The projection apparatus according to claim 6, wherein
The projection apparatus, wherein the semiconductor light emitting element is a semiconductor light emitting diode. The projection apparatus according to claim 6, wherein
The projection apparatus, wherein the semiconductor light emitting element is a semiconductor laser. The projection apparatus according to any one of claims 1 to 8,
The projection apparatus, wherein the color light switching unit switches the color light to irradiate the light beam according to a timing defined according to the color light. The projection apparatus according to claim 9 , wherein
The projection apparatus characterized in that the time for which the light flux of green color light is irradiated is longer than the time for which the light flux of other color light is irradiated. Projector comprising a projection device according to any one of claims 1 to 10.

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