JP2011145368A - Projector and method for adjusting color balance of projected image in projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a projector showing no degradation in the color balance of a projected image with lapse of time. <P>SOLUTION: The projector 1000 includes: an illumination device 10 having a solid light source device 20 that emits light including two color beams from different light sources; a color separating and guiding optical system 200 having a function of separating the illumination light from the illumination device 10 into a plurality of color beams; liquid crystal optical modulation devices 400R, 400G, 400B modulating the plurality of color beams in accordance with image information; and a projection optical system 600. The projector further includes: a light quantity monitor 700 measuring the light quantities of the two color beams and outputting as light quantity information; and a control unit 800 adjusting the color balance of a projected image by controlling the emission quantity of the solid light source device 20 and the modulation amount of the liquid crystal optical modulation device 400B based on the light quantity information of each color beam outputted by the light quantity monitor 700. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a projector and a color balance adjustment method for a projected image in the projector.

  2. Description of the Related Art Conventionally, a white solid light source device that has a blue solid light source that emits blue light and a fluorescent layer that converts part of the blue light into fluorescence including red light and green light and emits white light as illumination light is known. It has been. Further, an illumination device including the white solid light source device, a color light separation unit that separates illumination light from the illumination device into a plurality of color lights, and a light that modulates the plurality of color lights from the color light separation unit according to image information A projector is known that includes a modulation device and a projection optical system that projects modulated light from the light modulation device as a projection image (see, for example, Patent Document 1).

  According to the conventional projector, it is possible to project a full-color projection image while using a solid light source (blue solid light source) that emits monochromatic light.

JP 2008-268639 A

  However, in a conventional projector, two colored lights emitted from a white solid light source device with different light sources ("blue light" using a blue solid light source as a light source and "red light using a fluorescent layer as a light source) Or “green light”) (“blue light amount” and “red light amount or green light amount”) with various factors (for example, temperature change, deterioration over time, etc.). The light intensity of the light source changes, the light emission wavelength changes, and the light emission efficiency of the fluorescent layer changes.) The color balance of the projected image in the projector becomes worse over time. There is a problem.

  Accordingly, the present invention has been made to solve the above-described problem, and an object thereof is to provide a projector in which the color balance of a projected image does not deteriorate with the passage of time. It is another object of the present invention to provide a method for adjusting the color balance of a projected image in a projector that does not deteriorate the color balance of the projected image over time.

[1] A projector according to the present invention includes an illumination device including a light source device that emits light including at least two color lights having different light emission sources, and color light separation means that separates illumination light from the illumination device into a plurality of color lights. A light modulation device that modulates the plurality of color lights from the color light separation means according to image information, and a projection optical system that projects the modulated light from the light modulation device as a projection image, A light amount monitor that measures the light amounts of the two color lights and outputs them as light amount information, and the light emission amount of the light source device and the modulation amount of the light modulation device based on the light amount information of each color light output by the light amount monitor. And a control unit that adjusts the color balance of the projected image by controlling.

  Therefore, according to the projector of the present invention, the light emission amount of the light source device and the modulation amount of the light modulation device are controlled based on the light amount information obtained by measuring each of the two color lights having different light emission sources. Since the control unit for adjusting the color balance of the projected image is provided, the color balance of the projected image does not deteriorate even if the light amounts of the two color lights described above change with the passage of time. .

[2] In the projector according to the aspect of the invention, the light source device emits a blue solid light source that emits blue light as the light emission source, and converts a part of the blue light into fluorescence including red light and green light. It is preferable to have a fluorescent layer and emit white light including the blue light and the fluorescence.

  Even when the light source device is a white solid light source device having the above-described configuration, “color light using a blue solid light source as a light source (blue light)” and “color light using a fluorescent layer as a light source ([a] red) By controlling the light emission amount of the light source device and the modulation amount of the light modulation device based on the light amount information obtained by measuring each of “light, [b] green light or [c] mixed color light)” It is possible to adjust the color balance of the projected image.

[3] In the projector according to the aspect of the invention, it is preferable that the fluorescent layer includes a yellow phosphor that emits fluorescence including red light, green light, and yellow light when excited by blue light.

  Even when the fluorescent layer is a fluorescent layer as described above, “color light using a blue solid light source as a light source (blue light)” and “color light using a fluorescent layer as a light source ([a] red light, [b] Controlling the light emission amount of the light source device and the modulation amount of the light modulation device based on the light amount information obtained by measuring each of “green light, [c] yellow light, or [d] mixed color light)”. Thus, the color balance of the projected image can be adjusted.

[4] In the projector according to the aspect of the invention, the fluorescent layer includes a red phosphor that emits fluorescence including red light when excited by blue light, and fluorescence that includes green light when excited by blue light. It is preferable to contain the green phosphor to be emitted.

  Even when the fluorescent layer is a fluorescent layer as described above, “color light using a blue solid light source as a light source (blue light)” and “color light using a fluorescent layer as a light source ([a] red light, [b] The color balance of the projected image is controlled by controlling the light emission amount of the light source device and the modulation amount of the light modulation device based on the light amount information obtained by measuring each of “green light or [c] color light in which these are mixed”). Adjustments can be made.

[5] In the projector according to the aspect of the invention, the light modulation device includes a plurality of light modulation devices that modulate red light, green light, and blue light, and the light amount monitor measures a light amount of the blue light. A first light amount monitor that outputs the first light amount; and a second light amount monitor that measures the light amount of at least one color light included in the light emitted from the fluorescent layer and outputs the second light amount, and the control unit Calculates a ratio between the first light amount output from the first light amount monitor and the second light amount output from the second light amount monitor, and is based on the ratio between the first light amount and the second light amount. It is preferable to control the light emission amount of the light source device and the modulation amount of the light modulation device.

  In the case where the projector is a three-plate projector, by configuring as described above, the first light amount measured for blue light and at least one color light (for example, [[ a) red light, [b] green light, [c] yellow light, or [d] color light in which these are appropriately mixed) and the light emission amount of the light source device and the light modulation device It is possible to adjust the color balance of the projected image by controlling the modulation amount.

[6] In the projector according to the aspect of the invention, the light modulation device may be a single time division drive type light modulation device, and the color light separation unit may separate the illumination light emitted from the illumination device by a time division method. A rotating color wheel that generates at least the plurality of color lights,
The light quantity measurement monitor measures the light quantity of the blue light when the blue light emitted from the blue solid light source is irradiated on the light modulation device, outputs the light quantity as a first light quantity, and emits the fluorescent light emitted from the fluorescent layer. When the light modulation device is irradiated with at least one color light, the light quantity of the at least one color light is measured and output as a second light quantity, and the control unit outputs the second light quantity from the light quantity monitor. It is preferable to calculate a ratio between the first light amount and the second light amount, and to control the light emission amount of the light source device and the modulation amount of the light modulation device based on the ratio of the first light amount and the second light amount. .

  In the case where the projector is a projector including a single time-division drive type light modulation device, by configuring as described above, the first light amount measured for blue light and the light emitted from the fluorescent layer can be reduced. Based on a ratio with a second light amount measured for at least one color light (for example, [a] red light, [b] yellow light, [c] green light, or [d] color light in which these are appropriately mixed) By controlling the light emission amount of the light source device and the modulation amount of the light modulation device, the color balance of the projected image can be adjusted.

[7] In the projector according to the aspect of the invention, the control unit controls a light emission amount of the light source device so that a value of the second light amount is constant, and a ratio between the first light amount and the second light amount. Based on the above, it is preferable to control the modulation amount of the blue light in the light modulation device.

  With this configuration, the brightness of the projected image does not vary with time. In addition, since the control unit only needs to control the modulation amount only for the blue light, the modulation amount can be easily controlled.

[8] A method for adjusting a color balance of a projected image in a projector according to the present invention separates illumination light emitted from a light source device that emits light including at least two color lights having different light emission sources, and separates the light into a plurality of color lights. Then, a method for adjusting the color balance of a projected image in a projector that modulates the plurality of color lights with a light modulation device according to image information and projects the modulated light as a projected image, wherein the light amounts of the two color lights are measured. A light amount measuring step that outputs the light amount information, and the light emission amount of the light source device and the modulation amount of the light modulation device are controlled based on the light amount information of each color light output in the light amount measuring step. And a color balance adjustment step for performing color balance adjustment.

  For this reason, according to the color balance adjustment method of the projected image in the projector of the present invention, the light emission amount and the light modulation of the light source device based on the light amount information obtained by measuring each of the two color lights having different light emission sources. Since it is possible to adjust the color balance of the projected image by controlling the amount of modulation of the apparatus, even if the light amounts of the two color lights described above change with the passage of time, the projected image The color balance will not deteriorate.

FIG. 2 is a plan view showing an optical system of the projector 1000 according to the first embodiment. 1 is a cross-sectional view of a solid state light source device 20 according to Embodiment 1. FIG. 3 is a graph showing the light emission intensity characteristics of the solid-state light source 24 and the light emission intensity characteristics of the phosphor in the first embodiment. FIG. 2 is a block diagram illustrating a control system of the projector 1000 according to the first embodiment. 6 is a graph shown for explaining the operation principle of the control unit 800 in the projector 1000 according to the first embodiment. 6 is a flowchart illustrating a method for adjusting a color balance of a projected image in the projector 1000 according to the first embodiment. FIG. 9 is a diagram for explaining a projector 1002 according to a second embodiment. 6 is a graph showing the emission intensity characteristics of each phosphor in the second embodiment. FIG. 6 is a block diagram showing a control system of a projector 1002 according to a second embodiment. FIG. 10 is a plan view showing an optical system of a projector 1004 according to a modification. 10 is a graph shown for explaining the operation principle of the control unit 802 in a projector 1006 (not shown) according to Modification 2.

  The projector of the present invention will be described below based on the embodiments shown in the drawings.

[Embodiment 1]
FIG. 1 is a plan view showing an optical system of a projector 1000 according to the first embodiment.
FIG. 2 is a cross-sectional view of the solid-state light source device 20 according to the first embodiment.
FIG. 3 is a graph showing the emission intensity characteristics of the solid-state light source 24 and the emission intensity characteristics of the phosphor in the first embodiment. FIG. 3A is a graph showing the emission intensity characteristics of the solid light source 24, and FIG. 3B is a graph showing the emission intensity characteristics of the yellow phosphor contained in the fluorescent layer. Luminescence intensity characteristics are the characteristics of what wavelength of light is emitted with what intensity when a voltage is applied to a solid light source and excitation light is incident on a phosphor. Say. The vertical axis of the graph represents relative light emission intensity, and the light emission intensity at the wavelength where the light emission intensity is strongest is 1. The horizontal axis of the graph represents the wavelength.
FIG. 4 is a block diagram illustrating a control system of the projector 1000 according to the first embodiment.
1, 3, and 4, the symbol R indicates red light, the symbol G indicates green light, the symbol B indicates blue light, and the symbol Y indicates yellow light.

First, the configuration of the projector 1000 according to the first embodiment will be described.
As shown in FIGS. 1 and 4, the projector 1000 according to the first embodiment includes an illumination device 10, a color separation / light guiding optical system 200, three liquid crystal light modulation devices 400 </ b> R, 400 </ b> G, and 400 </ b> B, and a cross dichroic prism 500. A projection optical system 600, a light amount monitor 700, and a control unit 800.
Thereafter, the configuration of the projector 1000 is changed to (a) the optical system of the projector 1000 (mainly the illumination device 10, the color separation light guide optical system 200, the three liquid crystal light modulation devices 400R, 400G, 400B, the cross dichroic prism 500, and the projection optical system). 600) and (b) the control system of the projector 1000 (mainly the light quantity monitor 700 and the control unit 800).

(A) Optical system of projector 1000 The illuminating device 10 includes a solid light source device 20, a collimating optical system 30, and a rod integrator optical system 40.

  The solid-state light source device 20 is a light source device that emits light including colored light (blue light and fluorescence, which will be described later) with different light emitting sources. Specifically, as shown in FIG. 2, the solid light source device 20 is a light emitting diode having a base 22, a solid light source 24, a fluorescent layer 26, and a sealing member 28, and includes red light, green light, blue light, and This is a white solid light source device that emits white light including yellow light (see FIGS. 3A and 3B). The solid-state light source device 20 has lead wires and the like in addition to the above-described components, but illustration and description thereof are omitted.

The base 22 is a base on which the solid light source 24 is mounted.
The solid light source 24 is a blue solid light source that emits blue light (peak of emission intensity: about 460 nm, see FIG. 3A) as main excitation light. The solid light source 24 is mainly composed of gallium nitride and has a pn junction type structure. Note that the solid light source may not have a pn junction type structure, and may have a double heterojunction type, a quantum well junction type, or the like.
A reflective layer (not shown) is formed between the solid light source 24 and the base 22, and the blue light emitted from the solid light source 24 to the base 22 side is directed to the fluorescent layer 26 side by the reflective layer. Reflected.

The fluorescent layer 26 is a fluorescent layer that converts a part of blue light into fluorescent light including red light and green light and emits the fluorescent light. The fluorescent layer 26 includes a layer containing a yellow phosphor that emits fluorescence including red light, green light, and yellow light when excited by blue light, and is disposed on the illuminated region side of the solid light source 24. . The yellow phosphor is composed of YAG phosphor (Y, Gd) ₃ (Al, Ga) ₅ O ₁₂ : Ce. The yellow phosphor may be composed of a phosphor other than those described above. For example, the yellow phosphor may be composed of a YAG phosphor, a silicate phosphor, a TAG phosphor, or the like other than those described above.
The fluorescent layer 26 uses blue light emitted from the solid light source 24 as red light (peak of emission intensity: about 610 nm), green light (peak of emission intensity: about 540 nm), and yellow light (peak of emission intensity: The light is converted into about 580 nm and emitted (see FIG. 3B).

  The sealing member 28 is made of a transparent epoxy resin and protects the solid light source 24 and the fluorescent layer 26.

  As shown in FIG. 1, the collimating optical system 30 includes a first lens 32 that is a convex meniscus lens that suppresses the spread angle of light from the solid-state light source device 20, and a convex lens that substantially parallelizes the light from the first lens 32. And has a function of making the light from the solid-state light source device 20 substantially parallel as a whole. Note that the collimating optical system may include only one lens, or may include three or more lenses. In short, the collimating optical system only needs to have a function of collimating light from the solid-state light source device 20 as a whole.

The rod integrator optical system 40 includes a convex lens 42, an integrator rod 44 and a convex lens 46.
The convex lens 42 collects the parallel light from the collimating optical system 30 and guides it to the incident surface of the integrator rod 44.
The integrator rod 44 is a solid columnar rod, which makes light incident from the incident surface uniform by multiple reflection on the inner surface, and emits light having a uniform in-plane light intensity distribution from the emission surface. As the integrator rod, a hollow columnar rod can be used in place of the solid columnar rod.
The convex lens 46 substantially collimates the light emitted from the exit surface of the integrator rod 44 and guides the light to the image forming areas in the liquid crystal light modulation devices 400R, 400G, and 400G.
Note that a lens integrator optical system including a plurality of lens arrays and superimposing lenses can be used instead of the rod integrator optical system.

  The color separation light guide optical system 200 includes dichroic mirrors 210, 230, and 240, a partial transmission mirror 220, a reflection mirror 250, and relay lenses 260 and 270. The color separation light guide optical system 200 separates the light from the illumination device 10 into red light, green light, blue light, and yellow light, and each color light of red light, green light, and blue light is liquid crystal light that is an illumination target. It has a function of guiding light to the modulation devices 400R, 400G, and 400B. That is, the color separation light guide optical system 200 has a function as color light separation means.

The dichroic mirrors 210, 230, and 240 are mirrors in which a wavelength selective transmission film that reflects light in a predetermined wavelength region and passes light in another wavelength region is formed on a substrate.
The dichroic mirror 210 reflects red light, green light, and yellow light, and transmits blue light.
The dichroic mirror 230 reflects green light and allows red light and yellow light to pass therethrough.
The dichroic mirror 240 reflects red light and allows yellow light to pass through.
The partial transmission mirror 220 basically has the same configuration as that of the dichroic mirror, but reflects most of the incident blue light and transmits a part thereof.
The reflection mirror 250 reflects red light.

The red light reflected by the dichroic mirror 210 passes through the dichroic mirror 230, and further passes through the relay lens 260, the dichroic mirror 240, the relay lens 270, and the reflection mirror 250, and the image forming area of the liquid crystal light modulation device 400R for red light. Is incident on. The relay lenses 260 and 270, the dichroic mirror 240, and the reflection mirror 250 have a function of guiding the red light component that has passed through the dichroic mirror 230 to the liquid crystal light modulation device 400R.
The green light reflected by the dichroic mirror 210 is further reflected by the dichroic mirror 230 and enters the image forming area of the liquid crystal light modulation device 400G for green light.
Most of the blue light that has passed through the dichroic mirror 210 is reflected by the partial transmission mirror 220 and enters the image forming region of the liquid crystal light modulation device 400B for blue light. Part of the blue light that has passed through the partial transmission mirror 220 is incident on a first light amount monitor 710 (described later).
The yellow light reflected by the dichroic mirror 210 passes through the dichroic mirror 230, the relay lens 260, and the dichroic mirror 240 in order, and enters the second light amount monitor 720 (described later).

  The reason why such relay lenses 260 and 270 are provided in the optical path of the red light is that the length of the optical path of the red light is longer than the length of the optical path of the other color light. This is to prevent a decrease in usage efficiency. The projector 1000 according to the first embodiment has such a configuration because the length of the optical path of red light is long. However, the length of the optical path of blue light is increased and the relay lenses 260 and 270 are connected to the blue light. A configuration for use in the optical path is also possible.

The liquid crystal light modulation devices 400R, 400G, and 400B form color images by modulating incident color light according to image information, and are illumination targets of the illumination device 10. Although not shown, between the reflection mirror 250 and the liquid crystal light modulation device 400R, between the dichroic mirror 230 and the liquid crystal light modulation device 400G, and between the partial transmission mirror 220 and the liquid crystal light modulation device 400B, Each of the incident side polarizing plates is interposed, and between each of the liquid crystal light modulation devices 400R, 400G, and 400B and the cross dichroic prism 500, the outgoing side polarizing plate is interposed. The incident-side color light is modulated by the incident-side polarizing plate, the liquid crystal light modulation devices 400R, 400G, and 400B and the emission-side polarizing plate.
The liquid crystal light modulators 400R, 400G, and 400B are transmissive liquid crystal light modulators in which a liquid crystal that is an electro-optical material is hermetically sealed in a pair of transparent glass substrates. In accordance with the received image signal, the polarization direction of one type of linearly polarized light emitted from the incident side polarizing plate is modulated.
Since the projector 1000 includes three liquid crystal light modulation devices, the projector 1000 is a so-called three-plate projector.

  The cross dichroic prism 500 is an optical element that forms a color image by synthesizing an optical image modulated for each color light emitted from the emission side polarizing plate. The cross dichroic prism 500 has a substantially square shape in plan view in which four right-angle prisms are bonded together, and a dielectric multilayer film is formed on a substantially X-shaped interface in which the right-angle prisms are bonded together. The dielectric multilayer film formed at one of the substantially X-shaped interfaces reflects red light, and the dielectric multilayer film formed at the other interface reflects blue light. By these dielectric multilayer films, the red light and the blue light are bent and aligned with the traveling direction of the green light, so that the three color lights are synthesized.

  The color image emitted from the cross dichroic prism 500 is enlarged and projected by the projection optical system 600 to form an image on the screen SCR.

(A) Control system of projector 1000 As shown in FIG. 4, the light quantity monitor 700 measures the first light quantity monitor 710 that measures the quantity of blue light and the quantity of yellow light contained in the light emitted from the fluorescent layer. And a second light quantity monitor 720. The first light quantity monitor 710 outputs the measured blue light quantity as the first light quantity. The second light quantity monitor 720 outputs the measured yellow light quantity as the second light quantity. The light amount monitor 700 outputs the first light amount and the second light amount as light amount information.

  The control unit 800 includes a light source device control unit 810 that controls the light emission amount of the solid-state light source device 20, and a light modulation device control unit 820 that controls the modulation amount of the liquid crystal light modulation device 400B for blue light. The control unit 800 controls the light emission amount of the solid-state light source device 20 and the modulation amount of the liquid crystal light modulation device 400B based on the light amount information of the blue light and the light amount information of the yellow light output from the light amount monitor 700, thereby projecting the projected image. Adjust the color balance. Specifically, the control unit 800 calculates a ratio between the first light amount output from the first light amount monitor 710 and the second light amount output from the second light amount monitor 720, and the first light amount and the second light amount are calculated. Based on this ratio, the light emission amount of the solid-state light source device 20 and the modulation amount of the liquid crystal light modulation device 400B are controlled. In this case, the modulation amount control refers to controlling the modulation amount of the liquid crystal light modulation device 400B so that the color balance of the projected image can be achieved. Therefore, when an all white image as an image source is displayed on the projection screen, an all white image as a display image is displayed.

  The control unit 800 controls the light emission amount of the solid light source device 20 (the light emission amount of blue light of the solid light source 24) so that the value of the second light amount (yellow light amount) is constant (hereinafter, the light emission). The amount control is referred to as APC (auto power control).) And the liquid crystal light modulator based on the ratio of the first light quantity (blue light quantity) and the second light quantity (yellow light quantity). The modulation amount of 400B is controlled. Since yellow light, red light, and green light are emitted from the same light source (phosphor layer 26), the amount of yellow light, the amount of red light, and the amount of green light change with the same tendency. Therefore, by controlling the light emission amount of the solid light source device 20 so that the value of the second light amount (yellow light amount) is constant, the red light amount and the green light amount are also constant. As a result, the color balance can be adjusted by controlling the modulation amount for the remaining blue light.

Hereinafter, the operation principle of the controller 800 will be described in detail with reference to FIG.
FIG. 5 is a graph shown for explaining the operation principle of the control unit 800 in the projector 1000 according to the first embodiment. 5A and 5B show the emission intensity (blue light emission intensity) of the solid light source 24 and the emission intensity (green light, yellow light or red light) of the fluorescent layer 26 when the solid light source device 20 is turned on. FIG. 5C is a diagram showing how the light intensity of each color (blue light) on the projection screen when the solid-state light source device 20 is turned on and an all-white image is projected on the projection screen. It is a figure which shows how the brightness | luminance of (green light and red light) changes. 5A shows the light emission intensity when the control unit 800 is not adjusting the light emission amount in the solid light source device 20, and FIG. 5B is the control unit 800 adjusting the light emission amount in the solid light source device 20. FIG. 5C shows the light emission intensity when the modulation amount is not adjusted in the liquid crystal light modulation device 400B, and FIG. 5C shows the light emission amount adjustment in the solid-state light source device 20 and the modulation in the liquid crystal light modulation device 400B. Indicates the luminance when the amount is adjusted together. 5A to 5C, the vertical axis of the graph represents the relative light emission intensity or relative luminance when the light emission intensity or luminance immediately after lighting is 1, and the horizontal axis of the graph is from lighting. Represents time. It is assumed that color balance is achieved immediately after lighting. In FIGS. 5A and 5B, the symbol B indicates the emission intensity (blue light) of the solid light source 24, and the symbol Y indicates the emission intensity (yellow light) of the fluorescent layer 26. In FIG.5 (c), the code | symbol R, G, B shows the brightness | luminance of the blue light in a projection screen, green light, and red light, respectively.

1. When the control unit 800 does not adjust the light emission amount in the solid light source device 20, in the projector 1000 according to the first embodiment, as shown in FIG. As time passes, both the emission intensity of the solid light source 24 (emission intensity of blue light) and the emission intensity of the fluorescent layer 26 (emission intensity of green light, yellow light, or red light) tend to gradually decrease. At this time, the emission intensity of the fluorescent layer 26 (emission intensity of green light, yellow light, or red light) tends to be stronger than the emission intensity of the solid light source 24 (emission intensity of blue light). This is presumed to be caused by the temperature of the solid light source device 20 rising as time passes after the solid light source device 20 is turned on.

  Therefore, in this case, even if the solid light source device 20 is turned on and an all white image is projected on the projection screen, the color balance gradually deteriorates as the time elapses after the solid light source device 20 is turned on (bluish). Become). In addition, the brightness of the entire projection screen gradually decreases.

2. When the control unit 800 adjusts the light emission amount in the solid light source device 20 and does not adjust the modulation amount in the liquid crystal light modulation device 400B, in this case, the control unit 800 displays the light emission intensity (green light, yellow light) of the fluorescent layer 26. In order to control the light emission amount of the solid light source device 20 so that the value of the light emission intensity of light or red light is constant, the time after the solid light source device 20 is turned on as shown in FIG. Even after the passage of time, the emission intensity of the fluorescent layer 26 (emission intensity of green light, yellow light, or red light) remains constant. On the other hand, as shown in FIG. 5B, the emission intensity of the solid light source 24 (blue light emission intensity) increases as the time elapsed since the solid light source device 20 was turned on.

  Therefore, in this case, the decrease in the brightness of the entire projection screen is corrected (the brightness of the projected image gradually increases), but the deterioration of the color balance is not corrected.

3. In this case, the control unit 800 adjusts the light emission intensity (green light, yellow light) of the fluorescent layer 26 when the control unit 800 adjusts the light emission amount in the solid-state light source device 20 and the modulation amount in the liquid crystal light modulation device 400B. In addition, since the light emission amount of the solid-state light source device 20 is controlled so that the value of the light emission intensity of red light) becomes constant, and further, the modulation amount of blue light in the liquid crystal light modulation device 400B is controlled, FIG. As shown in c), the luminance of each color light (blue light, green light, and red light) on the projection screen does not change even if the time after the solid light source device 20 is turned on has elapsed.

  Therefore, in this case, the brightness of the entire projection screen is always constant, and the color balance does not deteriorate.

  Therefore, according to the projector 1000 according to the first embodiment, since the control unit 800 as described above is provided, two color lights (“color light using a solid light source as a light source”) and “fluorescent layer as a light source as time passes. Even if the amount of “colored light”) changes according to different ways of changing, the color balance of the projected image does not deteriorate.

  Next, a method for adjusting the color balance of the projected image in the projector 1000 according to the first embodiment will be described. FIG. 6 is a flowchart illustrating a method for adjusting the color balance of a projected image in the projector 1000 according to the first embodiment.

  As shown in FIG. 6, the method for adjusting the color balance of the projected image in the projector 1000 according to the first embodiment includes a light amount measurement step S1 and a color balance adjustment step S2.

A. Light quantity measurement step S1
The light amount measuring step S1 is a step of measuring the light amounts (first light amount and second light amount) of two color lights (blue light and yellow light) and outputting them as light amount information. The light quantity measurement step S1 is performed by the light quantity monitor 700 (the first light quantity monitor 710 and the second light quantity monitor 720).

B. Color balance adjustment step S2
The color balance adjustment step S2 is based on the light amount information including the light amount of the blue light (first light amount) and the light amount of the yellow light (second light amount) output in the light amount measurement step S1. In this step, the color balance of the projected image is adjusted by controlling the modulation amount of the liquid crystal light modulation device 400B. Specifically, the ratio between the first light amount and the second light amount is calculated, and the light emission amount of the solid-state light source device 20 and the modulation amount of the liquid crystal light modulation device 400B are calculated based on the ratio between the first light amount and the second light amount. To control. The color balance adjustment step S2 is performed by the control unit 800.

  In the color balance adjustment method of the projected image in the projector 1000 according to the first embodiment, first, the light amount measurement monitor performs the light amount measurement step S1 for example every minute. Next, a control part implements color balance adjustment step S2 based on the obtained light quantity information.

  Note that the timing of performing the light quantity measurement step S1 is not limited to every minute, and can be arbitrarily determined, for example, every frame, every second, every 10 minutes.

  Next, the effect of the projector 1000 according to the first embodiment and the effect of the color balance adjustment method of the projected image in the projector 1000 according to the first embodiment will be described.

  According to the projector 1000 according to the first embodiment, the light emission amount of the solid-state light source device 20 and the liquid crystal are based on the light amount information obtained by measuring each of two color lights (blue light and yellow light) having different light emission sources. Since the control unit 800 that adjusts the color balance of the projected image by controlling the modulation amount of the light modulation device 400B is provided, even if the light amounts of the two color lights described above change due to different changes with time. Thus, the color balance of the projected image is not deteriorated.

  Further, according to the projector 1000 according to the first embodiment, the solid-state light source device 20 converts the solid-state light source 24 that emits blue light as a light source, and a part of the blue light into fluorescence including red light and green light. Even in the case of a white solid light source device that has a fluorescent layer 26 that emits light and emits white light including blue light and fluorescence, “color light using the solid light source 24 as a light source (blue light)” and “fluorescence Based on the light amount information obtained by measuring each of the “color light (yellow light) having the layer 26 as a light source”, the projection image is controlled by controlling the light emission amount of the solid-state light source device 20 and the modulation amount of the liquid crystal light modulation device 400B. Color balance adjustment can be performed.

  In the projector 1000 according to the first embodiment, when the fluorescent layer 26 is a fluorescent layer containing a yellow phosphor that emits fluorescence including red light, green light, and yellow light when excited by blue light. The solid-state light source is also based on the light quantity information obtained by measuring each of “color light using the solid light source 24 as a light source (blue light)” and “color light using the fluorescent layer 26 as a light source (yellow light)”. By controlling the light emission amount of the device 20 and the modulation amount of the liquid crystal light modulation device 400B, the color balance of the projected image can be adjusted.

  In the projector 1000 according to the first embodiment, the light modulation device includes the liquid crystal light modulation devices 400R, 400G, and 400B, the light amount monitor 700 includes the first light amount monitor 710 and the second light amount monitor 720, and is controlled. The unit 800 calculates a ratio between the first light amount output from the first light amount monitor 710 and the second light amount output from the second light amount monitor 720, and based on the ratio between the first light amount and the second light amount, In order to control the light emission amount of the solid light source device 20 and the modulation amount of the liquid crystal light modulation device 400B, the light emission amount of the solid light source device 20 and the modulation amount of the liquid crystal light modulation device 400B based on the ratio of the first light amount and the second light amount. By controlling this, it is possible to adjust the color balance of the projected image.

  Further, according to the projector 1000 according to the first embodiment, the control unit 800 controls the light emission amount of the solid light source device 20 so that the value of the second light amount is constant, and the ratio between the first light amount and the second light amount. Since the modulation amount of the liquid crystal light modulation device 400B for blue light is controlled based on the above, the brightness of the projected image does not vary with time. Further, since the control unit 800 only needs to control the modulation amount for only blue light, the control of the modulation amount can be easily performed.

  According to the color balance adjustment method of the projected image in the projector 1000 according to the first embodiment, since the light quantity measurement step S1 and the color balance adjustment step S2 are included, two color lights (blue light and yellow light) having different light emission sources are included. ), The color balance of the projected image can be adjusted by controlling the light emission amount of the solid-state light source device 20 and the modulation amount of the liquid crystal light modulation device 400B based on the light amount information obtained by measuring each of the above. Even if the light amounts of the two color lights described above change with time, the color balance of the projected image does not deteriorate.

[Embodiment 2]
FIG. 7 is a diagram for explaining a projector 1002 according to the second embodiment. FIG. 7A is a plan view showing the optical system of the projector 1002 according to the second embodiment, and FIG. 7B is a front view showing the rotary color wheel 202.
FIG. 8 is a graph showing the emission intensity characteristics of each phosphor in the second embodiment. FIG. 8A is a graph showing the emission intensity characteristic of the red phosphor contained in the fluorescent layer 27, and FIG. 8B is a graph showing the emission intensity characteristic of the green phosphor contained in the fluorescent layer 27. FIG.
FIG. 9 is a block diagram illustrating a control system of the projector 1002 according to the second embodiment.
7-9, the code | symbol R shows red light, the code | symbol G shows green light, and the code | symbol B shows blue light.

The projector 1002 according to the second embodiment basically has the same configuration as that of the projector 1000 according to the first embodiment. However, the configuration of the illumination device, the color light separation unit, the light modulation device, and the light amount monitor is the projector according to the first embodiment. 1000 is different. Accordingly, the configuration of the control unit is different from that of the projector 1000 according to the first embodiment in that a relay optical system is provided.
Hereinafter, the configuration of the projector 1002 will be described. Note that description of matters similar to those of the first embodiment is omitted as appropriate.

As illustrated in FIG. 7A, the illumination device 12 includes a solid light source device 21, a collimating optical system 30, and a condenser lens 48.
The solid light source device 21 basically has the same configuration as that of the solid light source device 20 in the first embodiment, but the configuration of the fluorescent layer 27 (not shown) is different. The fluorescent layer 27 includes a red phosphor that emits fluorescence including red light when excited by blue light, and a green phosphor that emits fluorescence including green light when excited by blue light. Consists of. The red phosphor is made of, for example, CaAlSiN ₃ red phosphor. The green phosphor is, for example, a β sialon green phosphor. Each phosphor is not limited to those described above, and other phosphors can be used as long as each color light is emitted by light from a solid light source.
The fluorescent layer 27 converts the blue light emitted from the solid light source 24 into red light (emission intensity peak: about 640 nm) and green light (emission intensity peak: about 540 nm), respectively, and emits it (FIG. 8). (See (a) and FIG. 8 (b).)

  The condensing lens 48 condenses the parallel light from the collimating optical system 30 and guides it to the incident surface of the integrator rod 50 via the rotary color wheel 202 (described later).

The rotary color wheel 202 is color light separation means that separates illumination light emitted from the illumination device 12 by a time division method to generate red light, green light, and blue light, and is rotationally driven by the color wheel driving device 280. The The color wheel driving device 280 has, for example, a motor, and rotationally drives the rotary color wheel 202 by the motor.
As shown in FIG. 7A, the rotary color wheel 202 is disposed immediately before the entrance surface of the integrator rod 50.
As shown in FIG. 7B, the rotary color wheel 202 includes a red light passing region 204R that allows red light to pass therethrough, a green light passing region 204G that allows green light to pass therethrough, and a blue light passing region 204B that allows blue light to pass. Are arranged along the circumferential direction. Each passing region transmits predetermined color light by reflecting or absorbing color light other than the predetermined color light emitted by each passing region. The rotary color wheel 202 separates and emits the white light from the illuminating device 12 as a color light string composed of red light, green light, and blue light by the above-described respective color light passing regions by a time division method.

  The integrator rod 50 is a solid columnar rod, which makes each color light incident from the incident surface uniform by multiple reflection on the inner surface, and emits each color light having a uniform in-plane light intensity distribution from the emission surface. As the integrator rod, a hollow columnar rod can be used in place of the solid columnar rod.

As shown in FIG. 7A, the relay optical system 60 includes a relay lens 62, a partial transmission mirror 64, and a field lens 66. The relay optical system 60 guides the color light train from the integrator rod 50 to the micromirror light modulator 402.
The relay lens 62 condenses the color light columns emitted from the integrator rod 50 so as to form an image on the image modulation region of the micromirror light modulator 402.
The partial transmission mirror 64 reflects most of the incident color light row toward the micromirror light modulator 402 and allows a part thereof to pass. The color light train that has passed through the partial transmission mirror 64 enters a light amount monitor 702 (described later).
Although the detailed description is omitted, the field lens 66 guides the color light train from the partial transmission mirror 64 to the micromirror light modulator 402 and projects the color light train from the micromirror light modulator 402 to the projection optical system 602. A lens for guiding light to

  The micromirror type light modulation device 402 is a single time-division drive type light modulation device. Specifically, the color mirror from the relay optical system 60 is converted by a micromirror corresponding to each pixel according to image information. This is a reflection direction control type light modulation device having a function of reflecting and emitting the light toward the projection optical system 602. Although the detailed description is omitted, the micromirror light modulator 402 is disposed at a position conjugate with the exit surface of the integrator rod 50.

  The projection optical system 602 projects a color light string representing a projection image from the micromirror light modulator 402 on the external screen SCR as a projection image. The micromirror light modulator 402 and the projection optical system 602 are arranged so that their central axes coincide.

  On the screen SCR, a red projection image, a green projection image, and a blue projection image are sequentially projected while being switched. However, since these switching speeds are sufficiently fast, It is recognized as a color image by the eyes.

  As shown in FIG. 9, the light amount monitor 702 measures the amount of blue light when the blue light emitted from the solid light source 24 is irradiated on the micromirror-type light modulation device 402 and outputs it as a first light amount. When the red light contained in the fluorescence emitted from the fluorescent layer is irradiated on the light modulation device, the light amount of the red light is measured and output as the second light amount.

  The control unit 804 includes a light source device control unit 810 that controls the light emission amount of the solid light source device 21 and a light modulation device control unit 822 that controls the modulation amount of the micromirror light modulation device 402. The control unit 802 calculates a ratio between the first light amount and the second light amount output from the first light amount monitor, and based on the ratio between the first light amount and the second light amount, the light emission amount of the solid light source device 21 and the micro light amount. The modulation amount of the mirror type light modulation device 402 is controlled.

  Hereinafter, effects of the projector 1002 according to the second embodiment will be described.

  As described above, the projector 1002 according to the second embodiment is different from the projector 1000 according to the first embodiment in the configuration of the illumination device, the color light separation unit, the light modulation device, the light amount monitor, and the like, but has a different emission source. The color of the projected image is controlled by controlling the light emission amount of the solid-state light source device 21 and the modulation amount of the micromirror light modulation device 402 based on the light amount information obtained by measuring each of the two color lights (blue light and red light). Since the control unit 802 that performs the balance adjustment is provided, similarly to the projector 1000 according to the first embodiment, even if the light amounts of the two color lights described above change with time, the color of the projected image changes. The balance will not get worse.

  In addition, according to the projector 1002 according to the second embodiment, the fluorescent layer 27 emits a red phosphor that emits fluorescence including red light when excited by blue light, and emits green light when excited by blue light. Even in the case of a fluorescent layer containing a green phosphor that emits fluorescent light, each of “color light using a solid light source 24 as a light source (blue light)” and “red light using a fluorescent layer 27 as a light source” It is possible to adjust the color balance of the projected image by controlling the light emission amount of the solid-state light source device 21 and the modulation amount of the micromirror light modulation device 402 based on the light amount information obtained by measuring the above.

  As mentioned above, although this invention was demonstrated based on said embodiment, this invention is not limited to said embodiment. The present invention can be carried out in various modes without departing from the spirit thereof, and for example, the following modifications are possible.

(1) In Embodiment 1 above, the amount of yellow light was measured as the amount of colored light using the fluorescent layer 26 as a light source, but the present invention is not limited to this. FIG. 10 is a plan view showing an optical system of a projector 1004 according to the first modification. In FIG. 10, reference numeral 252 denotes a partial transmission mirror that reflects most of the red light and transmits a part thereof. In the projector of the present invention, as in the projector 1004 according to the first modification, red light may be measured as the amount of color light using the fluorescent layer as a light source. In addition, as the color light using the fluorescent layer as the light source, the amount of green light may be measured, or the amount of color light mixed with red light, green light, or the like may be measured. In the projector having such a configuration, a light emitting source that does not emit yellow light can be used.

(2) In the first embodiment, the emission intensity of the fluorescent layer 26 (green light, yellow light, or red light emission intensity) tends to decrease more strongly than the emission intensity of the solid light source 24 (blue light emission intensity). However, the present invention is not limited to this example.

  FIG. 11 is a graph for explaining the operation principle of the control unit 804 in the projector 1006 (not shown) according to the second modification. In the projector 1006 according to the modified example 2, the light emission intensity (blue light emission intensity) of the solid light source 24 tends to decrease more strongly than the light emission intensity (green light, yellow light, or red light emission intensity) of the fluorescent layer 26. It shall be in 11A and 11B show the emission intensity of the solid light source 24 (emission intensity of blue light) and the emission intensity of the fluorescent layer 26 (green light, yellow light or red light) when the solid light source device 20 is turned on. 11 (c) shows how the light intensity of the color changes in the projection screen when the solid light source device 20 is turned on and an all white image is projected onto the projection screen. It is a figure which shows how the brightness | luminance of (green light and red light) changes. 11A shows the light emission intensity when the control unit 804 does not adjust the light emission amount in the solid light source device 20, and FIG. 11B shows the light emission intensity in the solid light source device 20 adjusted by the control unit 804. FIG. 11C shows the light emission intensity when the adjustment of the modulation amount in the liquid crystal light modulation device 400B is not performed, and FIG. 11C shows the adjustment of the light emission amount in the solid light source device 20 and the modulation in the liquid crystal light modulation device 400B. Indicates the luminance when the amount is adjusted together. 11A to 11C, the vertical axis of the graph represents the relative light emission intensity or relative luminance when the light emission intensity or luminance immediately after lighting is 1, and the horizontal axis of the graph is from lighting. Represents time. Note that immediately after lighting, the emission intensity of the solid light source 24 (emission intensity of blue light) is relatively stronger than the emission intensity of the fluorescent layer 26 (emission intensity of green light, yellow light, or red light). In FIGS. 11A and 11B, the symbol B indicates the emission intensity (blue light) of the solid light source 24, and the symbol Y indicates the emission intensity (yellow light) of the fluorescent layer 26. In FIG. 11C, symbols R, G, and B respectively indicate the luminances of blue light, green light, and red light on the projection screen.

  In the present invention, as in the case of the projector 1006 according to the second modification, the emission intensity of the solid light source 24 (emission intensity of blue light) is the emission intensity of the fluorescent layer 26 (emission of green light, yellow light, or red light). Even if it tends to decrease more strongly than the intensity, immediately after lighting, the emission intensity of the solid light source 24 (emission intensity of blue light) becomes the emission intensity of the fluorescent layer 26 (green light, yellow light or red light). 11, the control unit 804 controls the modulation amount of the blue light in accordance with this, and as shown in FIG. 11, the projector according to the first embodiment. As in the case of 1000, color balance adjustment can be performed.

(3) In the second embodiment, the amount of red light is measured as the amount of color light using the fluorescent layer 27 as a light source, but the present invention is not limited to this. The amount of green light may be measured as the amount of color light using the fluorescent layer as the light source. Alternatively, the light amount of red light and the light amount of green light may be measured, and the average value thereof may be used as the second light amount.

(4) In Embodiment 1 described above, the fluorescent layer 26 contains a yellow phosphor that emits fluorescence including red light, green light, and yellow light, but the present invention is not limited to this. For example, the fluorescent layer may contain a red phosphor that emits red light and a green phosphor that emits green light. In Embodiment 2, the fluorescent layer 27 includes a red phosphor that emits red light and a green phosphor that emits green light. However, the present invention is not limited to this. For example, the fluorescent layer may contain a yellow phosphor that emits fluorescence including red light, green light, and yellow light.

(5) In each of the above embodiments, the solid-state light source device 20 including the solid-state light source 24 and the light-emitting diode having the fluorescent layer 26 is used as the light source device that emits light including at least two color lights with different light-emitting sources. However, the present invention is not limited to this. A semiconductor laser having a solid light source and a fluorescent layer, an organic light emitting diode having a solid light source and a fluorescent layer, or the like may be used. A light source other than a solid light source (for example, a high-pressure mercury lamp, a halogen lamp, etc.) and a light source device having a fluorescent layer may be used.

(6) In each of the above-described embodiments, the solid-state light source device 20 including the solid-state light source 24 and the light-emitting diode having the fluorescent layer 26 is used as the light source device that emits light including at least two color lights with different emission sources. However, the present invention is not limited to this. For example, a light source device having two types of solid light sources may be used. Moreover, you may use the light source device which has two types of light sources other than a solid light source. Moreover, you may use the light source device which has light sources other than a solid light source, and a solid light source.

(7) Although the transmissive projector is used in the first embodiment, the present invention is not limited to this. For example, a reflective projector may be used. Here, “transmission type” means that a light modulation device as a light modulation means such as a transmission type liquid crystal display device transmits light, and “reflection type” This means that the light modulation device as the light modulation means, such as a reflective liquid crystal display device, is a type that reflects light. Even when the present invention is applied to a reflective projector, the same effect as that of a transmissive projector can be obtained.

(8) In the second embodiment, the micromirror type light modulation device 402 is used as a single time division drive type light modulation device, but the present invention is not limited to this. A transmission type liquid crystal light modulation device, a reflection type liquid crystal light modulation device, or the like may be used as a single time division drive type light modulation device.

(9) In the first embodiment, a polarization conversion device may be further provided on the incident surface side of the integrator rod 50. The polarization conversion device is a polarization conversion element that converts light including both one polarization component and the other polarization component into substantially one type of linearly polarized light having a uniform polarization direction.

(10) In the first embodiment, the projector using three liquid crystal light modulation devices has been described as an example. However, the present invention is not limited to this. The present invention can also be applied to a projector using one, two, four or more liquid crystal light modulation devices.

(11) The present invention can be applied to a rear projection type projector that projects from a side opposite to the side that observes the projected image, even when applied to a front projection type projector that projects from the side that observes the projected image. Is also possible.

(12) In the second embodiment, the rotary color wheel 202 includes the red light passage region 204R, the green light passage region 204G, and the blue light passage region 204B. However, the present invention is not limited to this. Absent. The rotary color wheel may further include a color light passage region other than the above. Moreover, you may further have the area | region (For example, white passage area | region which passes all of red light, green light, and blue light) through which several color light is passed.

(13) In the first embodiment, the control unit 800 controls the modulation amount of the liquid crystal light modulation device 400B for blue light, but the present invention is not limited to this. For example, the light modulation device for red light and the light modulation device for green light may be controlled, or all the light modulation devices may be controlled.

DESCRIPTION OF SYMBOLS 10, 12, 14 ... Illuminating device, 20, 21 ... Solid light source device, 22 ... Base, 24 ... Solid light source, 26 ... Fluorescent layer, 28 ... Sealing member, 30 ... Collimating optical system, 32 ... 1st lens, 34 ... second lens, 40 ... rod integrator optical system, 42, 46 ... convex lens, 44, 50 ... integrator rod, 48 ... condensing lens, 60 ... relay optical system, 62, 260, 270 ... relay lens, 64, 220 252 ... Partially transmitting mirror 66 ... Field lens 200 ... Color separation light guide optical system 202 ... Rotating color wheel 204R ... Red light passing area 204G ... Green light passing area 204B ... Blue light passing area 210 , 230, 240 ... Dichroic mirror, 250 ... Reflection mirror, 280 ... Color wheel drive device, 400R, 400G, 400B ... Liquid Light modulator 402, micromirror light modulator, 500 cross dichroic prism, 600 projection optical system, 700, 702 light quantity monitor, 710 first light quantity monitor, 720, 730 second light quantity monitor, 800, 802, 804 ... control unit, 810 ... light source device control unit, 820, 822 ... light modulation device control unit, 1000, 1002, 1004 ... projector, SCR ... screen

Claims (8)

An illuminating device including a light source device that emits light including at least two color lights having different light emission sources;
Color light separating means for separating the illumination light from the illumination device into a plurality of color lights;
A light modulation device that modulates the plurality of color lights from the color light separation means according to image information;
A projector including a projection optical system that projects the modulated light from the light modulation device as a projection image,
A light amount monitor that measures the light amount of the two color lights and outputs the light amount information;
A control unit that adjusts the color balance of the projected image by controlling the light emission amount of the light source device and the modulation amount of the light modulation device based on the light amount information of each color light output by the light amount monitor; Projector. The projector according to claim 1.
The light source device includes, as the light emitting source, a blue solid light source that emits blue light, and a fluorescent layer that converts a part of the blue light into fluorescence including red light and green light, and emits the blue light. And a white light containing the fluorescence. The projector according to claim 2,
The phosphor layer includes a yellow phosphor that emits fluorescence including red light, green light, and yellow light when excited by blue light. The projector according to claim 2,
The phosphor layer includes a red phosphor that emits fluorescence including red light when excited by blue light, and a green phosphor that emits fluorescence including green light when excited by blue light. Projector. The projector according to claim 2,
The light modulator comprises a plurality of light modulators that modulate each of red light, green light, and blue light,
The light amount monitor measures a light amount of blue light and outputs it as a first light amount, and measures a light amount of at least one color light included in light emitted from the fluorescent layer and outputs it as a second light amount. And a second light quantity monitor that
The control unit calculates a ratio between the first light amount output from the first light amount monitor and the second light amount output from the second light amount monitor, and calculates the ratio between the first light amount and the second light amount. A projector that controls a light emission amount of the light source device and a modulation amount of the light modulation device based on a ratio. The projector according to claim 2,
The light modulation device comprises a single time division drive type light modulation device,
The color light separating means comprises a rotary color wheel that separates the illumination light emitted from the illumination device by a time division method to generate at least the plurality of color lights,
The light quantity measurement monitor measures the light quantity of the blue light when the blue light emitted from the blue solid light source is irradiated on the light modulation device, outputs the light quantity as a first light quantity, and emits the fluorescent light emitted from the fluorescent layer. When at least one color light included in the light is irradiated on the light modulation device, the light amount of the at least one color light is measured and output as a second light amount,
The control unit calculates a ratio between the first light amount and the second light amount output from the light amount monitor, and based on the ratio between the first light amount and the second light amount, the light emission amount of the light source device And a projector for controlling a modulation amount of the light modulation device. The projector according to claim 5 or 6,
The control unit controls a light emission amount of the light source device so that a value of the second light amount is constant, and based on a ratio between the first light amount and the second light amount, a blue color in the light modulation device. A projector characterized by controlling a light modulation amount. After separating the illumination light emitted from the light source device that emits light including at least two color lights of different light emission sources into a plurality of color lights, the plurality of color lights are separated by a light modulation device according to image information. A method for adjusting the color balance of a projected image in a projector that modulates and projects modulated light as a projected image,
A light amount measuring step of measuring the light amounts of the two color lights and outputting them as light amount information;
A color balance adjustment step for adjusting the color balance of the projected image by controlling the light emission amount of the light source device and the modulation amount of the light modulation device based on the light amount information of each color light output in the light amount measurement step. A method for adjusting a color balance of a projected image in a projector, comprising:

Images