JP2019184823A - Projection type video display device - Google Patents

Abstract

To provide a projection type video display device that has inexpensive constitution without greatly spoiling the number of displayable pixels nor lightness.SOLUTION: A projection type video display device comprises: a light source part which emits, on a time-division basis, first component lights having wavelength bands of two colors selected out of the three primary colors, and second component lights having a wavelength band common to a first component light and a different wavelength band from the first component light; a first video display element which performs brightness modulation on a component light having the wavelength band common to the second component light between first component lights color-separated by a color separation part according to pixel information corresponding to the component light, and performs brightness modulation on a component light having the wavelength band common to the first component light between color-separated second component lights according to pixel information corresponding to the wavelength band; and a second video display element which performs brightness modulation on a component light having the different wavelength band from a second component light between the first component lights according to pixel information corresponding to the wavelength band, and also performs brightness modulation on a component light having the different wavelength band from the first component light between the second component lights.SELECTED DRAWING: Figure 2

Description

  The present disclosure relates to a projection display apparatus such as a projector.

The projector of Patent Document 1
(1) a light source emitting at least red, green and blue light;
(2) light separating means for separating the light source into three components of red, green, and blue;
(3) a first liquid crystal panel that is inserted into an optical path of green light and whose luminance is modulated by green image information;
(4) a second liquid crystal panel that is inserted into the optical path of red light and blue light, and whose luminance is modulated by red and blue image information;
(5) light combining means for combining light transmitted through the first and second liquid crystal panels;
(6) projection means for projecting the light synthesized by the light synthesis means on a screen;
Is provided.

  Therefore, according to the projector of Patent Document 1, the optical system can be configured easily and inexpensively without causing significant image quality degradation.

JP-A-3-261933

  However, in the projector of Patent Document 1, since it is necessary to independently modulate the luminance of the red light and the blue light in the second liquid crystal panel, the number of pixels of the red light and the blue light is halved. This is not efficient because the luminance loss of the minute increases.

  An object of the present disclosure is to solve the above-described problems and to provide an efficient projection-type image display apparatus that reduces luminance loss as compared with the prior art.

A projection display apparatus according to an aspect of the present disclosure is provided.
A first component light having a wavelength band of two colors selected from red, green, and blue, and a second component light having a wavelength band common to the first component light and a wavelength band different from the first component light A light source unit that emits light in a time-sharing manner,
A color separation unit for color-separating the first component light and the second component light from the light source unit respectively into two predetermined wavelength bands;
Out of the first component light color-separated by the color separation unit, the component light having the same wavelength band as the second component light is subjected to luminance modulation according to the pixel information corresponding to the wavelength band, and the light after luminance modulation is output. The component light having a wavelength band common to the first component light among the second component light color-separated by the color separation unit is converted to pixel information corresponding to the wavelength band or the wavelength band and at least another wavelength. A first image display element that performs luminance modulation in accordance with pixel information corresponding to a band and outputs light after luminance modulation;
Of the first component light, the component light having a wavelength band different from that of the second component light is subjected to luminance modulation according to the pixel information corresponding to the wavelength band, and the light after luminance modulation is output. A second video display element for performing luminance modulation on component light having a wavelength band different from the component light according to pixel information corresponding to the wavelength band and outputting light after luminance modulation;
A light combining unit that combines the light from the first video display element and the light from the second video display element to output combined light;
A projection unit that projects the synthesized light synthesized by the light synthesis unit onto a screen.

  Therefore, according to the present disclosure, it is possible to increase the light utilization efficiency that has been impaired in the related art while maintaining an inexpensive and simple optical configuration.

1 is an external perspective view showing an example of the overall configuration of a projector according to Embodiment 1. FIG. It is a block diagram which shows the example of an internal structure of the projector of FIG. FIG. 3 is a plan view of the phosphor wheel in FIG. 2. FIG. 4 is a longitudinal sectional view taken along line A-A ′ of FIG. 3. FIG. 4 is a longitudinal sectional view taken along line B-B ′ of FIG. 3. It is a top view of the color wheel of FIG. It is a spectrum figure which shows the transmission wavelength band of the color wheel of FIG. 3 is a timing chart illustrating a first control example of the projector in FIG. 2. It is a block diagram which shows the functional structural example of the control part of the projector of FIG. 6 is a timing chart illustrating a second control example of the projector in FIG. 2. 6 is a timing chart illustrating a third control example of the projector in FIG. 2. 10 is a timing chart illustrating a fourth control example of the projector in FIG. 2. 10 is a timing chart illustrating a fifth control example of the projector in FIG. 2. 10 is a timing chart illustrating a sixth control example of the projector in FIG. 2. 10 is a timing chart illustrating a seventh control example of the projector in FIG. 2. 3 is a timing chart showing a control example of the projector of FIG. 2. FIG. 5 is a block diagram illustrating an internal configuration example of a projector according to a second embodiment. It is a top view of the fluorescent substance wheel of Drawing 11A. It is a timing chart which shows the example of control of the projector of FIG. 11A. FIG. 10 is a block diagram illustrating an internal configuration example of a control unit of a projector according to a third embodiment. It is a timing chart which shows the example of control of the control part of the projector of FIG.

  Hereinafter, a projector that is a projection display apparatus according to an embodiment of the present disclosure will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, it should be noted that the drawings are schematic and ratios of dimensions and the like are different from actual ones. Therefore, specific dimensions and the like should be determined in consideration of the following description. Moreover, it is a matter of course that portions having different dimensional relationships and ratios are included between the drawings.

(Embodiment 1)
The first embodiment will be described below with reference to FIGS. Hereinafter, a projector will be described as a specific embodiment of the projection display apparatus according to the present disclosure.

  FIG. 1 is an external perspective view showing an example of the overall configuration of a projector P1 according to the first embodiment. In FIG. 1, the projector P <b> 1 forms a projected display image 102 by projecting the projected video light 101 generated according to the video signal onto the projection surface or the like of the screen 27.

[1-1] Configuration of Projector P1 Hereinafter, an internal configuration of the projector P1 will be described.

  FIG. 2 is a block diagram showing an example of the internal configuration of the projector P1 shown in FIG.

  2, the projector P1 includes a light source unit 60, a rod integrator 19, a color wheel 28, a relay optical system 20, a dichroic mirror 24, image display elements 1 and 2, a prism 25, and a projection lens 26. It is configured with. Here, the light source unit 60 includes the blue laser light source 11, the excitation optical system 10, and the phosphor wheel 17. The excitation optical system 10 includes lenses 12 and 13, a dichroic mirror 14, a wave plate 15, and lenses 16 and 18.

  The light from the laser light source 11 is separated and reflected by the dichroic mirror 14 through the lenses 12 and 13 and then enters the phosphor wheel 17 through the lens 16. The phosphor wheel 17 is rotated by a motor 17M whose rotation is controlled by the phosphor wheel controller 42, and is converted into a predetermined color and reflected as will be described in detail later, and the reflected light is converted into a lens 16, a wave plate 15, and a dichroic mirror. 14 and the lens 18 and enter the input end of the rod integrator 19. The rod integrator 19 makes the light from the light source unit 60 uniform and enters the dichroic mirror 24 via the color wheel 28 and the relay optical system 20. The color wheel 28 is rotated by a motor 28 </ b> M whose rotation is controlled by a color wheel controller 43. Next, the dichroic mirror 24 performs color separation into two colors, and outputs light of one color to the video display element 1 via the prism 25 and outputs the other color to the video display element 2. Each of the video display elements 1 and 2 modulates the incident light according to the corresponding pixel information of the input video signal, and then modulates the two lights subjected to the luminance modulation into a prism 25 that combines the two lights. Projection is performed on the screen 27 via the projection lens 26.

  FIG. 3 is a plan view of the phosphor wheel 17 of FIG. 4A is a longitudinal sectional view taken along line A-A ′ of FIG. 3, and FIG. 4B is a longitudinal sectional view taken along line B-B ′ of FIG. 3.

  In FIG. 3, the phosphor wheel 17 is composed of two phosphor regions of 180 degrees each. In the present embodiment, the phosphor wheel 17 is composed of a yellow phosphor 32 region and a green phosphor 33 region. In the former region of the yellow phosphor 32, as shown in FIG. 4A, the yellow phosphor 32 is formed on the wheel substrate 30 via the adhesive layer 31. In the latter region of the green phosphor 34, as shown in FIG. 4B, the green phosphor 33 is formed on the wheel substrate 30 via the adhesive layer 31, and the transflective film 34 is further formed thereon. Is done.

  The laser light source 11 is configured by juxtaposing a plurality of blue laser light sources in a two-dimensional shape. When blue excitation light from the laser light source 11 enters the yellow phosphor 32 of the phosphor wheel 17, first component light composed of red component light and green component light generated from the excited yellow phosphor 32 is generated. The Further, when the excitation light from the blue laser light source 11 is incident on the green phosphor 33 of the phosphor wheel 17, the first light composed of green component light and blue component light from the green phosphor 33 having the excited transflective film 34. Two component light is generated.

  FIG. 5 is a plan view of the color wheel 38 of FIG. The color wheel 38 is rotationally controlled in synchronization with the rotation of the phosphor wheel 17, and is synchronized with the region of the yellow light transmitting portion 35 that is rotationally controlled in synchronization with the region of the yellow phosphor 32 and the region of the green phosphor 33. And a red trimming unit 36 whose rotation is controlled.

  6 is a spectrum diagram showing the wavelength bands of the first component light that has passed through the yellow light transmitting portion 35 and the second component light that has passed through the red trimming portion 36 in the color wheel 38 of FIG. The dichroic mirror 24 of the color separation unit in FIG. 2 reflects the light component in the green band out of the light components from the color wheel 28 and outputs the reflected light component to the image display element 2 via the prism 25, while in the blue and red bands. After transmitting the light component, the light component is output to the image display element 1 through the prism 25.

  FIG. 7 shows a control example of the projector P1 of FIG. 2, for example, the display color and video display of the video display element 1 when the phosphor wheel 17 is rotated at a triple speed with respect to a video signal of one frame of 60 Hz. 3 is a timing chart showing the display color of the element 2 and the display color of the screen 27. FIG. Since the configuration of the light component in the green band reflected by the dichroic mirror 24 is different between the first component light and the second component light, the color of the first component light in the green band is the first green G1, and the green color of the second component light is If the color of the band is the second green G2, the timing of each green G1, G2 displayed in a time division manner is as shown in FIG.

  During the period in which the first component light is emitted, the red band component light R is guided to the video display element 1 and the green band component light G1 is guided to the video display element 2. In the period in which the second component light is emitted, the blue band component light B is guided to the video display element 1 and the green band component light G2 is guided to the video display element 2. Here, each component light whose luminance has been modulated by the video display element 1 and the video display element 2 is guided to the prism 25 of the color synthesis unit, and projected onto the screen 27 via the projection lens 26. For example, when the image display element 1 and the image display element 2 are subjected to luminance modulation so that the luminance on the screen 27 becomes 100%, the first component light displayed in time division is yellow Ye, second The component light becomes cyan C on the screen 27.

[1-2] Configuration of Control Unit 40 FIG. 8 is a block diagram illustrating a functional configuration example of the control unit 40 of the projector P1 of FIG.

  8, the control unit 40 includes a main controller 50 having a memory 50m storing a predetermined program, a signal conversion circuit 41, a phosphor wheel controller 42, a color wheel controller 43, and a light source controller 44. Composed. Here, the main controller 50 is composed of, for example, a CPU, an MPU, and the like, and controls the overall operation of the projector P1 by executing a program stored in the memory 50m. The control unit 40 controls the phosphor wheel 17, the laser light source 11 of the light source unit 60, and the video display elements 1 and 2 in synchronization. In the present embodiment, the control unit 40 controls the operation of the laser light source 11 of the light source unit 60 based on a predetermined light source control timing (details will be described later) stored in the memory 50m. Further, the control unit 40 supplies the video signals of the respective colors to the video display elements 1 and 2 in a time-sharing manner based on predetermined video control timing (details will be described later) stored in the memory 50m.

  The function of the control unit 40 is realized by cooperation of hardware and software. However, the control unit 40 may be realized only by a hardware circuit configured exclusively for realizing a predetermined function. For example, the control unit 40 can be composed of not only a CPU and MPU, but also a DSP, FPGA, ASIC, and the like.

[1-3] Operation of Control Unit 40 The operation of projector P1 configured as described above will be described below with reference to FIG.

  The signal conversion circuit 41 receives a video signal from a video supply device such as a DVD player or a PC (personal computer) connected to the projector P1. Further, the signal conversion circuit 41 generates a synchronization signal (for example, 60 Hz) and supplies it to the phosphor wheel controller 42, the color wheel controller 43, and the light source controller 44.

  The signal conversion circuit 41 converts the received video signal into a video signal indicating a video having a resolution corresponding to the number of pixels of the video display elements 1 and 2. Further, the signal conversion circuit 41 indicates a green video signal indicating a green monochrome image, a blue video signal indicating a blue monochrome image, and a red monochrome image for each frame (1/60 second). Convert to red video signal. Here, the signal conversion circuit 41 synchronizes with the synchronization signal, based on a predetermined video control timing (details will be described later) in one cycle (1/180 seconds) of a frequency three times the frequency of the synchronization signal. The signal, the blue video signal, and the red video signal are supplied to the video display elements 1 and 2 in a time division manner, respectively.

  The phosphor wheel controller 42 controls the number of rotations of the phosphor wheel 17. Specifically, the phosphor wheel controller 42 has a rotation speed three times the rotation speed corresponding to the frequency of the synchronization signal from the signal conversion circuit 41 (for example, a rotation speed three times the rotation speed corresponding to 60 Hz, that is, The number of rotations of the motor 17M is controlled at 1/180 second).

  The color wheel controller 43 controls the number of rotations of the color wheel 28. Specifically, the color wheel controller 43 has a rotation speed three times the rotation speed corresponding to the frequency of the synchronization signal from the signal conversion circuit 41 (for example, a rotation speed three times the rotation speed corresponding to 60 Hz, that is, 1 The number of rotations of the motor 28M is controlled at 1 rotation per 180 seconds).

  The light source controller 44 controls the operation of the laser light source 11 by controlling the drive circuit 45. Specifically, the light source controller 44 synchronizes with the synchronization signal from the signal conversion circuit 41, and is one cycle (1/180 seconds) of a frequency three times the frequency of the synchronization signal (for example, a frequency three times 60 Hz). ), The operation of the laser light source 11 is controlled based on a predetermined light source control timing (details will be described later).

  FIG. 9 shows a control example of the projector P1 of FIG. 2, for example, the display color and video display of the video display element 1 when the phosphor wheel 17 is rotated at a triple speed with respect to a video signal of one frame of 60 Hz. 4 is a timing chart showing the display color of the element 2, the display color of the screen 27, and the on / off light amount of the laser light source 11. In particular, FIG. 9 shows an example of a timing chart of the light source control operation by the light source controller 44 of the control unit 40 of the projector P1 according to the first embodiment.

  In FIG. 9, as in FIG. 7, the phosphor wheel 17 is rotated once for a video signal (for example, 60 Hz) for a time corresponding to one period (1/180 seconds) of three times the frequency. Meanwhile, the light source controller 44 controls the light output of the laser light source 11 in accordance with the light emission period of each phosphor. The video display elements 1 and 2 perform luminance modulation corresponding to the video signals at the timing shown in FIG. Specifically, the luminance modulation of the red (R) period is performed according to the red video signal, the luminance modulation of the blue (B) period is performed according to the blue video signal, and the first green is performed according to the green video signal. Either or both of the luminance modulations are performed in the G1 period and the second green G2 period. Accordingly, when the luminance modulation is sequentially performed in the period of the first green G1 and the period of the second green G2 in accordance with the green video signal, the green brightness of the projector P1 is determined by the afterimage of the human eye. Since it is the sum of the period of green G1 and the period of second green G2, bright green can be displayed.

  Hereinafter, another control example by the control unit 40 will be described with reference to FIGS. 10A to 10F. 10A to 10F, the display of X% means that the display of the corresponding color is caused to emit light by PWM modulation for the time period of X% of the period.

  FIG. 10A is a control example of the projector P1 of FIG. 2, for example, the phosphor wheel 17 is rotated at a triple speed with respect to a video signal of one frame of 60 Hz, and the input video signal is (R, G , B) = (0%, 50%, 0%), the display color of the video display element 1, the display color of the video display element 2, the display color of the screen 27, and the on / down of the light amount of the laser light source 11. It is a timing chart which shows. At this time, the video display element 1 is controlled so that the amount of light is 0% in the red R period and the blue B period, and the video display element 2 is in the first green G1 period and the second green G2 period. Control is performed by the controller 40 so that the amount of light is 50%.

  FIG. 10B is a control example of the projector P1 of FIG. 2, for example, the phosphor wheel 17 is rotated at a triple speed with respect to a video signal of one frame of 60 Hz, and the input video signal is (R, G , B) = (50%, 70%, 40%), the display color of the video display element 1, the display color of the video display element 2, the display color of the screen 27, and the on / down reduction of the light quantity of the laser light source 11. It is a timing chart which shows. At this time, as in FIG. 10A, the video display element 1 is controlled by the control unit 40 so that the amount of light in the red R period is 50% and the period of blue B is 40%, as in FIG. 10A. Control is performed by the control unit 40 so that the amount of light in the first green G1 period and the second green G2 period is 70%. On the other hand, since the first green G1 of the first component light generated from the yellow phosphor 32 has a lot of yellow components, it is controlled by the control unit 40 as yellow, that is, the control unit 40 performs the red video signal and the green video signal. Luminance modulation may be performed according to both. Furthermore, FIG. 10C and FIG. 10D show an embodiment when the first green G1 is controlled as yellow.

  FIG. 10C is an example of control of the projector P1 of FIG. 2, and for example, the phosphor wheel 17 is rotated at a triple speed with respect to a video signal of one frame of 60 Hz, and the input video signal is (R, G , B) = (0%, 50%, 0%), the display color of the video display element 1, the display color of the video display element 2, the display color of the screen 27, and the on / down of the light amount of the laser light source 11. It is a timing chart which shows. Here, the yellow component is MIN (R, G) = 0%. Therefore, the video display element 1 is controlled by the control unit 40 so that the light amount becomes 0% during the red R period and the blue B period, and the video display element 2 has the light amount 0% during the first green G1 period. Control is performed by the control unit 40 so that the amount of light in the period of 2 green G2 is 50%.

  Note that MIN (A, B) is a minimum value function that returns the minimum values of the arguments A and B.

  FIG. 10D is a control example of the projector P1 in FIG. 2, for example, the phosphor wheel 17 is rotated at a triple speed with respect to a video signal of one frame of 60 Hz, and the input video signal is (R, G , B) = (50%, 70%, 40%), the display color of the video display element 1, the display color of the video display element 2, the display color of the screen 27, and the on / down reduction of the light quantity of the laser light source 11. It is a timing chart which shows. At this time, the yellow component is MIN (R, G) = 50%, and the video display element 1 is controlled by the control unit 40 so that the light amount is 50% during the red R period and 40% during the blue B period. The video display element 2 is controlled by the control unit 40 so that the amount of light in the first green G1 period is 50% and the amount of light in the second green G2 period is 70%.

  Since the second green light G2 of the second component light generated from the green phosphor 33 has a large blue component, it is controlled by the control unit 40 as cyan, that is, the control unit 40 controls both the blue video signal and the green video signal. The luminance modulation may be performed according to the above. Furthermore, FIG. 10E and FIG. 10F show an embodiment in which the second green G2 is controlled to be cyan.

  FIG. 10E is a control example of the projector P1 of FIG. 2, for example, the phosphor wheel 17 is rotated at a triple speed with respect to a video signal of one frame of 60 Hz, and the inputted video signal is (R, G , B) = (0%, 50%, 0%), the display color of the video display element 1, the display color of the video display element 2, the display color of the screen 27, and the on / down of the light amount of the laser light source 11. It is a timing chart which shows. At this time, the video display element 1 is controlled by the control unit 40 so that the light quantity is 0% during the red R period and the blue B period, and the video display element 2 is 50% light quantity during the first green G1 period. Control is performed by the controller 40 so that the amount of light in the second green G2 period is 0%.

  FIG. 10F is a control example of the projector P1 of FIG. 2, for example, the phosphor wheel 17 is rotated at a triple speed with respect to a video signal of one frame of 60 Hz, and the input video signal is (R, G , B) = (50%, 70%, 40%), the display color of the video display element 1, the display color of the video display element 2, the display color of the screen 27, and the on / down reduction of the light quantity of the laser light source 11. It is a timing chart which shows. At this time, the video display element 1 is controlled by the control unit 40 so that the light amount is 50% during the red R period and 40% during the blue B period, and the video display element 2 is light during the first green G1 period. Control is performed by the control unit 40 so that the amount of light in the period of 70% and the second green color G2 is 40%.

  Note that only the first green G1 or only the second green G2 may be subjected to luminance modulation according to the green video signal to provide green with high color purity.

  As described above, according to the present embodiment, for example, the video display element 1 displays red R or blue B, while the video display element 2 displays the first green G1 in synchronization with the red R. Alternatively, by displaying the second green G2 in synchronization with the blue B, yellow (Ye) is displayed in synchronization with the red R and the first green G1 on the screen 27, or the blue B In addition, cyan (C) can be displayed in synchronization with the second green G2, and can be selectively switched alternately in a time division manner. Further, when luminance modulation is sequentially performed in the period of the first green G1 and the period of the second green G2 according to the green video signal, the brightness of the green color of the projector P1 is determined by the afterimage of the human eye. Since it is the sum of the period of green G1 and the period of second green G2, bright green can be displayed. Therefore, since bright green or the like can be displayed as compared with the prior art, a low-cost configuration can be achieved without a decrease in luminance and a decrease in the number of pixels as in Patent Document 1.

(Embodiment 2)
FIG. 11A is a block diagram illustrating an internal configuration example of the projector P1 according to the second embodiment. In Embodiment 1 of FIG. 2A, in order to generate 1st component light and 2nd component light, the fluorescent substance layer from which the area | region of the yellow fluorescent substance 32 and the area | region of the green fluorescent substance 33 differ on the fluorescent substance wheel 17, for example It is characterized by providing. In contrast, in the second embodiment, first component light and second component light are generated from two independent laser light sources 111 and 112, respectively, and the generated first component light and second component light are selectively selected. It is characterized by high-speed switching in time division. Hereinafter, Embodiment 2 will be described with reference to FIGS. 11A to 12.

  In the projector P1 of FIG. 11A, the first component light output from the laser light source 111 in which the blue laser light source and the red laser light source are alternately juxtaposed in a two-dimensional shape, for example, is the lens 12, the first component light (blue component and It enters the dichroic mirror 24 via the rod integrator 19 for uniformizing (including the red component), the dichroic mirror 14A for allowing the first component light to pass through, and the lens 19B. On the other hand, the excitation light output from the laser light source 112 composed only of the blue laser light source passes through the phosphor wheel 17A having a yellow phosphor, so that the second component light containing the yellow component is emitted from the phosphor wheel 17A. Is output. The second component light is incident on the dichroic mirror 14A via the rod integrator 119 and the lens 119A that make the second component light uniform. The dichroic mirror 14A reflects the incident second component light and enters the dichroic mirror 24 via the lens 19B.

  Next, the dichroic mirror 24 has transmission and reflection characteristics different from those of the dichroic mirror 14A, and reflects the light component B in the blue band of the first component light and the light component G in the green band of the second component light. The first red R1 that is the light component in the red band of the one-component light and the second red R2 that is the light component in the red band of the second component light are transmitted. Then, the light component B in the blue band of the first component light and the light component G in the green band of the second component light reflected by the dichroic mirror 24 are output to the video display element 2 via the prism 25. The image display element 2 modulates the luminance of the light component B in the blue band of the first component light and the light component G in the green band of the second component light according to the input video signal, and then the prism 25 and the projection lens 26. Is projected onto the screen 27 via On the other hand, the first red R1 and the second red R2 transmitted by the dichroic mirror 24 are output to the video display element 1 via the prism 25. The video display element 1 modulates the brightness of the incident first red R1 and second red R2 in accordance with the input video signal, and then projects the luminance onto the screen 27 via the prism 25 and the projection lens 26.

  FIG. 11B is a plan view of the phosphor wheel 17A of FIG. 11A. In FIG. 11B, a yellow phosphor 32 is formed in a 360-degree region via an adhesive layer (not shown) on the wheel substrate 30B, and the phosphor wheel 17A has a region of the yellow phosphor 32 on almost the entire surface.

  FIG. 12 shows an example of control of the projector P1 in FIG. 11A. For example, when the phosphor wheel 17A is rotated at 6 × speed with respect to an image signal of one frame of 60 Hz, and the laser light sources 111 and 112 are alternately switched. 4 is a timing chart showing the display color of the video display element 1, the display color of the video display element 2, the display color of the screen 27, and on / off of the laser light sources 111 and 112. At this time, the laser light source 111 and the laser light source 112 are selectively switched alternately in a time-division manner in a period (1/360 seconds) of a frequency six times that of the video signal in one frame of the video signal (for example, 60 Hz). It is operating.

Therefore, as shown in FIG. 12, the following is displayed on the screen 27.
(1) In the first period in which the laser light source 111 is turned on and the laser light source 112 is turned off, the light of the first red R1 is projected from the image display element 1 onto the screen 27, while the blue B from the image display element 2 Is projected onto the screen 27. As a result, the screen 27 is displayed in magenta color M.
(2) In the second period in which the laser light source 111 is turned off and the laser light source 112 is turned on, the light of the second red R2 is projected from the image display element 1 onto the screen 27, while the green G is emitted from the image display element 2. Is projected onto the screen 27. As a result, the screen 27 is displayed in yellow Ye.
(3) Then, the first period and the second period are selectively switched in a time-division manner with a period (1/360 seconds) of a frequency six times that of the video signal. is doing.

  On the phosphor wheel 17 of the first embodiment, when switching between the first component light and the second component light, the first component light is switched by one phosphor wheel 17 having two regions, and the first component light is caused by an afterimage of human eyes. There is a problem that a color mixture period of light and second component light occurs, and if the color is switched at a higher speed, the color mixture period increases and the red, green, and blue periods decrease. On the other hand, according to the second embodiment, a single color wheel 17A having only one region is used, and the two laser light sources 111 and 112 are switched on / off at high speed, so that the color mixing period is achieved. Without increasing the color break, it is possible to reduce color breaks (referred to as color afterimage noise that does not become the original color due to color mixing).

(Embodiment 3)
FIG. 13 is a block diagram illustrating an internal configuration example of the control units 40 and 40A of the projectors P1 and P2 according to the third embodiment. In the first embodiment, the projector is composed of only one projector P1. On the other hand, the third embodiment is characterized in that two projectors P1 and P2 are used to project onto the same area. Note that three or more projectors may be used to project onto the same area. The third embodiment will be described below with reference to FIGS.

  In FIG. 13, two projectors P1 and P2 include control units 40 and 40A, respectively. Here, the configuration of the control unit 40 is different from that of the first embodiment only in the signal conversion circuit 41A, and the control unit 40A has the same configuration as the control unit 40 of the first embodiment. Other configurations are the same as those of the first embodiment. The signal conversion circuit 41A of the projector P1 shifts the synchronization signal (for example, 60 Hz) of the signal generation unit of the projector P1 by a half time of one period (1/180 seconds) of the triple frequency. The signal is output to the signal conversion circuit 41 of the control unit 40A of P2, and the signal conversion circuit 41 operates based on the synchronization signal. When the projector P2 receives a synchronization signal from the outside, the projector P2 operates based on the synchronization signal.

  FIG. 14 shows an example of control of the control units 40 and 40A of the projectors P1 and P2 in FIG. 13, and the phosphor wheel 17A is rotated at a 6 × speed with respect to, for example, a 60-Hz video signal of each projector P1 and P2. In addition, when the laser light sources 111 and 112 are alternately switched, the display color of the video display element 1, the display color of the video display element 2, the display color of the screen 27, and the ON / light quantity reduction of the laser light sources 111 and 112 are shown. It is a timing chart. At this time, the timing of the phosphor wheel 17 of the projector P2 is shifted by half the time of 1/180 seconds with respect to the timing of the phosphor wheel 17 of the projector P1, so that the R / R necessary for displaying one frame is displayed. All periods of B / G1 / G2 can be displayed simultaneously, and the display on the screen is always white (W) when both the video display elements 1 and 2 are 100% on.

  As described above, according to the third embodiment, the plurality of P1 and P2 are always white in each period of time display using two (or plural) projectors P1 and P2. By synchronizing these operations, color breaks can be reduced.

(Other embodiments)
Although the present disclosure has been described by using the above-described embodiments, it should not be understood that the descriptions and drawings constituting a part of this disclosure limit the present disclosure. From this disclosure, various alternative embodiments, examples and operational techniques will be apparent to those skilled in the art.

  In the first embodiment, the configuration using the color wheel 28 is disclosed. However, when a material having a small red wavelength band out of the wavelength bands generated from the green phosphor is used, the color wheel 28 for red trimming is not necessary. Obviously.

  In the second embodiment, the method of alternately turning on the laser light source 111 and the laser light source 112 has been disclosed. However, a period for turning on the light simultaneously may be provided.

  In the third embodiment, a method for outputting a synchronization signal from the projector P1 to the projector P2 has been disclosed. However, a mode for shifting the phase may be provided in advance. Specifically, the “EVEN mode” for driving the phosphor wheel 17 as in the projector P1 of FIG. 14 and the phase shift of the phosphor wheel 17 as in the projector P2 of FIG. An “ODD mode” may be provided.

  Also, in the case where two projectors P1 and P2 are used, an embodiment has been disclosed in which the phase of 180 degrees, which is 1/2 of 360 degrees, is shifted with respect to the reference synchronization signal. However, even if four projectors are used. For example, it is clear that the same effect can be obtained by shifting the phase of 1/4 or 1/2 (90 degrees or 180 degrees) of 360 degrees.

(Configuration 1) In the first embodiment, red R and blue B are selectively switched from the video display element 1 in a time-division manner, while the first green G1 and the second green G2 are selectively output from the video display element 2. The output is switched in time division.
(Configuration 2) In the second embodiment, the video display element 1 selectively outputs the first red R1 and the second red R2 by time division, while the video display element 2 selectively selects blue B and green G. The output is switched in time division.
However, you may similarly comprise as follows.
(Configuration 3) Red R and green G are selectively switched and output from one video display element in a time-division manner, while first blue B1 and second blue B2 are selectively time-division from the other video display element. Switch the output with. At this time, a magenta color M and a cyan color C are displayed on the screen 27, respectively.

These configurations 1 to 3 are summarized as follows.
(A) The light source unit includes a first component light having wavelength bands of two colors selected from red, green, and blue, a wavelength band common to the first component light, and a wavelength band different from the first component light. And the second component light having a time-division emission.
(B) The color separation unit separates the first component light and the second component light from the light source unit into two predetermined wavelength bands, respectively.
(C) The first image display element has a luminance of component light having a wavelength band common to the second component light among the first component light color-separated by the color separation unit according to pixel information corresponding to the wavelength band. Pixels corresponding to the wavelength band are output as light after modulation and luminance modulation, and component light having a wavelength band common to the first component light among the second component light color-separated by the color separation unit Luminance modulation is performed according to information or pixel information corresponding to at least one other wavelength band and the wavelength band, and light after luminance modulation is output.
(D) The second image display element performs luminance modulation on the component light having a wavelength band different from that of the second component light in the first component light according to the pixel information corresponding to the wavelength band, and outputs the light after luminance modulation. The component light having a wavelength band different from the first component light among the second component light is subjected to luminance modulation according to the pixel information corresponding to the wavelength band, and the light after luminance modulation is output.

  The present disclosure can be applied to a projection display apparatus such as a projector.

1, 2 Video display element 10 Excitation optical system 11 Laser light source 12, 13, 16, 18 Lens 14, 14A Dichroic mirror 15 Wave plate 17, 17A Phosphor wheel 17M Motor 19, 119 Rod integrator 19A, 19B, 119A Lens 20 Relay Optical system 21, 22, 23 Lens 24 Dichroic mirror 25 Prism 26 Projection lens 27 Screen 28 Color wheel 28M Motor 30, 30A, 30B Wheel substrate 31 Adhesive layer 32 Yellow phosphor 33 Green phosphor 34 Transflective film 35 Yellow light transmission Unit 36 red trimming unit 40, 40A control unit 41, 41A signal conversion circuit 42 phosphor wheel controller 43 color wheel controller 44 light source controller 45 drive circuit 50 main controller 50m memory 60 Light source 101 Projected image light 102 Projected display image 111.112 Laser light source P1, P2 Projector

Claims (6)

A first component light having a wavelength band of two colors selected from red, green, and blue, and a second component light having a wavelength band common to the first component light and a wavelength band different from the first component light A light source unit that emits light in a time-sharing manner,
A color separation unit for color-separating the first component light and the second component light from the light source unit respectively into two predetermined wavelength bands;
Out of the first component light color-separated by the color separation unit, the component light having the same wavelength band as the second component light is subjected to luminance modulation according to the pixel information corresponding to the wavelength band, and the light after luminance modulation is output. The component light having a wavelength band common to the first component light among the second component light color-separated by the color separation unit is converted to pixel information corresponding to the wavelength band or the wavelength band and at least another wavelength. A first video display element that performs luminance modulation according to pixel information corresponding to a band and outputs light after luminance modulation;
Of the first component light, the component light having a wavelength band different from that of the second component light is subjected to luminance modulation according to the pixel information corresponding to the wavelength band, and the light after luminance modulation is output. A second video display element for performing luminance modulation on component light having a wavelength band different from the component light according to pixel information corresponding to the wavelength band and outputting light after luminance modulation;
A light combining unit that combines the light from the first video display element and the light from the second video display element to output combined light;
A projection display apparatus comprising: a projection unit that projects the synthesized light synthesized by the light synthesis unit onto a screen. The first video display element performs luminance modulation on the selected red and blue and switches and outputs in a time-sharing manner,
The second image display element switches and outputs a first green having a green band of the first component light and a second green having a green band of the second component light in a time division manner. Item 4. A projection display apparatus according to Item 1. The first video display element performs luminance modulation on the selected blue and green and switches and outputs in a time-sharing manner,
The second video display element switches and outputs, in a time division manner, a first red color having a red band of the first component light and a second red color having a red band of the second component light. Item 4. A projection display apparatus according to Item 1. The light source unit is
A first laser light source that emits first component light;
The projection display apparatus according to any one of claims 1 to 3, further comprising a second laser light source that is provided independently of the first laser light source and emits second component light. Comprising at least two projection display devices according to any one of claims 1 to 4,
The at least two projection display devices project onto the same screen;
A projection display apparatus in which first component light and second component light are generated at different timings. Comprising at least two projection display devices according to any one of claims 1 to 4,
The at least two projection display devices project onto the same screen;
A projection display apparatus in which first component light and second component light are generated at the same timing.

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