JP5442221B2 - Illumination device and projection display device - Google Patents

Description

  The present invention relates to an illumination device and a projection display apparatus that modulates each color component light after separating white light emitted from a white light source into a plurality of color component lights.

  Conventionally, a color separation unit that separates white light emitted from a white light source into a plurality of color component lights (red component light R, green component light G, and blue component light B), and a plurality of lights that respectively modulate the plurality of color component lights A projection display apparatus having a modulation element is known.

  White light emitted from a white light source such as a UHP lamp includes yellow component light Ye in addition to red component light R, green component light G, and blue component light B. The yellow component light Ye has a wavelength band sandwiched between the wavelength band of the red component light R and the wavelength band of the green component light G.

  In general, such a white light source outputs a relatively large amount of light in the wavelength band of the yellow component light Ye. Therefore, there is an attempt to positively use the yellow component light Ye in order to improve the amount of image light projected by the projection display apparatus. However, although the amount of emitted light is increased by using the yellow component light Ye, the color purity is lowered.

  Here, examples of the projection display apparatus include a projection display apparatus used for home theaters and the like, and a projection display apparatus used for data output and the like.

  In a projection display apparatus used in a home theater or the like, it is preferable that the color purity of each color be given priority over the amount of emitted light. On the other hand, in a projection display apparatus used for data output or the like, it is preferable that the emitted light quantity has priority over the color purity of each color.

  As described above, it is desired to switch between a mode in which the color purity of each color is prioritized (hereinafter referred to as color purity priority mode) and a mode in which the amount of emitted light is prioritized (hereinafter referred to as light amount priority mode) depending on the application of the projection display apparatus. There is a need.

  On the other hand, a projection display apparatus using a dichroic filter capable of removing a predetermined wavelength band (for example, the wavelength band of yellow component light Ye) has been proposed (for example, Patent Document 1).

  Specifically, in the color purity priority mode, a dichroic filter is disposed on the optical path of the color component light, and in the light quantity priority mode, the dichroic filter is removed from the optical path of the color component light.

As a result, switching between the color purity priority mode and the light quantity priority mode is realized by a single projection display apparatus.
JP 2000-137289 A ([0028], [0029], FIG. 1 etc.)

  However, in the above-described projection display apparatus, since it is necessary to move the dichroic filter mechanically, a failure of a mechanism for moving the dichroic filter is likely to occur.

  Therefore, the present invention has been made to solve the above-described problem, and an illumination device and a projection display capable of switching between a color purity priority mode and a light amount priority mode while suppressing the occurrence of a failure. An object is to provide an apparatus.

A lighting device according to a first feature includes a color separation unit that separates white light emitted from a white light source into a plurality of color component lights, and red component light, green component light, and blue component light separated by the color separation unit. A lighting device including a light modulation element for modulating red component light, green component light, and blue component light, respectively , and a light incident side of the light modulation element for red component light, green component light, and blue component light equipped with a polarizing rotation element provided in said polarization rotation element, the polarization direction of said turning subject light by pre Symbol light modulation device transmitting once a convoluted object light which is part of the color component light to be led to the with swirling, said turning subject light, of the color component light to be guided before Symbol light modulator, a color component light having a wavelength band monochromatic color purity is high color purity component light outside the wavelength band of Has a wavelength band.

  According to this feature, the polarization rotator rotates the polarization direction of the rotation target light that is part of the color component light incident on the one light modulation element. Therefore, when the polarization rotator does not rotate the rotation target light, the rotation target light is transmitted through the one light modulation element, so that the light amount of the color component light emitted from the one light modulation element is increased (light amount priority). mode). On the other hand, when the polarization rotator rotates the rotation target light, the rotation target light is shielded by the polarizing plate (polarizing plate provided on the light incident side) of the one light modulation element, and the one light modulation element Therefore, the color purity of the color component light emitted from one light modulation element is increased (color purity priority mode).

  As described above, the lighting device malfunctions in comparison with the conventional technique in which the dichroic filter has to be mechanically moved to switch between the light amount priority mode and the color purity priority mode by electrically controlling the polarization rotator. Is suppressed.

  In the first feature, the polarization rotator is configured to be able to switch between a state in which the polarization direction of the rotation target light is rotated by 90 ° and a state in which the polarization direction of the rotation target light is not rotated.

  In the first feature, the polarization rotation element rotates the polarization direction of the rotation target light within a range of 0 ° to 90 °.

  In the first feature, the illumination device includes a control unit that controls the amount of rotation in the polarization direction of the rotation target light by the polarization rotation element in accordance with a video input signal used for modulation amount control of the plurality of light modulation elements. A control unit 300) is further provided.

  In the first feature, the control unit calculates the saturation of a pixel based on the video input signal, and the amount of rotation in the polarization direction of the rotation target light by the polarization rotation element based on the saturation. To control.

  In the first feature, the polarization rotator is a plurality of polarization rotators corresponding to each of the plurality of light modulation elements. The control unit calculates saturation for each of a plurality of hue ranges corresponding to each of the plurality of light modulation elements based on the video input signal, and sets the saturation calculated for each of the plurality of hue ranges. Based on this, the amount of rotation in the polarization direction of the rotation target light by the plurality of polarization rotation elements corresponding to each of the plurality of hue ranges is controlled.

  In the first feature, the control unit calculates a hue for each of a plurality of hue ranges corresponding to each of the plurality of light modulation elements based on the video input signal, and is calculated for each of the plurality of hue ranges. Based on the hue, the amount of rotation in the polarization direction of the rotation target light by the polarization rotation element is adjusted.

  In the first feature, the control unit calculates the luminance of a pixel based on the video input signal, and adjusts the amount of rotation in the polarization direction of the rotation target light by the polarization rotator based on the luminance. To do.

  In the first feature, the polarization rotator is constituted by a plurality of regions. The control unit calculates saturation for each of the plurality of regions based on the video input signal corresponding to each of the plurality of regions, and based on the saturation calculated for each of the plurality of regions, The amount of rotation in the polarization direction of the rotation target light by the polarization rotation element is controlled for each of the plurality of regions.

  In the first feature, the resolution of the polarization convolution element is lower than the resolution of the plurality of light modulation elements.

A projection display apparatus according to a second feature includes a color separation unit that separates white light emitted from a white light source into a plurality of color component lights, and red component light, green component light, and blue separated by the color separation unit. Projects light modulation elements for red component light, green component light, and blue component light that respectively modulate component light, and each color component light modulated by the light modulation elements for red component light, green component light, and blue component light A projection lens unit comprising: a polarization rotator provided on a light incident side of a light modulation element for red component light, green component light, and blue component light; and rotation element, with swirling the polarization direction of said turning subject light by causing the pre-Symbol light convoluted object light which is part of the color component light to be guided to the modulation element transmits once, said turning subject light, said light Of the color component light guided to the modulation element, single color Purity having a waveband outside the color component light at a high color purity component light having higher becomes wavelength band.

  According to the present invention, it is possible to provide an illumination device and a projection display apparatus that can switch between a color purity priority mode and a light amount priority mode while suppressing the occurrence of a failure.

  Hereinafter, a projection display apparatus according to an embodiment of the present invention 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.

[First Embodiment]
(Configuration of projection display device)
Hereinafter, the configuration of the projection display apparatus according to the first embodiment will be described with reference to the drawings. FIG. 1 is a diagram showing a configuration of a projection display apparatus 100 according to the first embodiment.

  As shown in FIG. 1, the projection display apparatus 100 includes a projection lens unit 110 and an illumination device 120.

  In FIG. 1, it should be noted that a fly-eye lens that homogenizes the light emitted from the light source 10, a PBS (Polarized Beam Splitter) that aligns the polarization direction of the light emitted from the light source 10, and the like are omitted.

  The projection lens unit 110 projects the image light emitted from the illumination device 120 onto a screen (not shown).

  The illumination device 120 includes a light source 10, a plurality of liquid crystal panels 30 (a liquid crystal panel 30R, a liquid crystal panel 30G, and a liquid crystal panel 30B), and a plurality of polarization rotators 40 (a polarization rotator 40R, a polarization rotator 40G, and a polarization rotator 40B. ) And a cross dichroic prism 50.

  The light source 10 is a UHP lamp that emits white light. That is, the light emitted from the light source 10 includes at least red component light R, green component light G, and blue component light B.

  The liquid crystal panel 30R modulates the red component light R in accordance with the video input signal (red input signal Rin). Similarly, the liquid crystal panel 30G and the liquid crystal panel 30B modulate the green component light G and the blue component light B according to the video input signals (the green input signal Gin and the blue input signal Bin).

  Here, these liquid crystal panels 30 are provided with polarizing plates (not shown) on the light incident side and the light emission side.

  The polarization rotator 40R is provided on the light incident side of the liquid crystal panel 30R. The polarization rotation element 40R rotates the polarization direction of rotation target light (hereinafter, rotation target light Rr) that is a part of the red component light R incident on the liquid crystal panel 30R. Here, in the mode in which the color purity of the red component light R is prioritized, the rotation target light Rr is a color component light (hereinafter referred to as a red high color purity component light Rt) having a wavelength band in which the color purity of red single color is high. It has a wavelength band outside the wavelength band. That is, the polarization rotator 40R is configured to be able to rotate the rotation target light Rr without rotating the red high color purity component light Rt.

  Here, the polarization rotation element 40R is an optical element configured to be able to selectively switch between a state in which the polarization direction of the rotation target light Rr is not rotated and a state in which the polarization direction of the rotation target light Rr is rotated 90 °. The polarization rotator 40R may be an optical element that rotates the polarization direction of the rotation target light Rr within the range of 0 ° to 90 °. Details of the polarization rotator 40R will be described later (see FIG. 3).

  Similarly, the polarization rotator 40G and the polarization rotator 40B are provided on the light incident side of the liquid crystal panel 30G and the liquid crystal panel 30B.

  The polarization rotation element 40G rotates the polarization direction of rotation target light (hereinafter referred to as rotation target light Gr) that is a part of the green component light G incident on the liquid crystal panel 30G. Here, in the mode in which the color purity of the green component light G is prioritized, the rotation target light Gr is a color component light (hereinafter, green high color purity component light Gt) having a wavelength band in which the color purity of a single green color is high. It has a wavelength band outside the wavelength band. That is, the polarization rotation element 40G is configured to be able to rotate the rotation target light Gr without rotating the green high-color purity component light Gt.

  The polarization rotation element 40B rotates the polarization direction of the rotation target light (hereinafter referred to as the rotation target light Br) that is a part of the blue component light B incident on the liquid crystal panel 30B. Here, in the mode in which the color purity of the blue component light B is prioritized, the rotation target light Br is a color component light having a wavelength band in which the color purity of a single blue color is high (hereinafter, blue high color purity component light Bt). It has a wavelength band outside the wavelength band. That is, the polarization rotator 40B is configured to be able to rotate the rotation target light Br without rotating the blue high color purity component light Bt.

  Similarly to the polarization rotation element 40R, the polarization rotation element 40G (or the polarization rotation element 40B) is in a state where the polarization direction of the rotation target light Gr (or rotation target light Br) is not rotated and the rotation target light Gr (or rotation). It is an optical element configured to be able to selectively switch the state in which the polarization direction of the target light Br) is rotated by 90 °. The polarization rotator 40G (or polarization rotator 40B) may be an optical element that rotates the polarization direction of the rotation target light Gr (or rotation target light Br) within a range of 0 ° to 90 °. .

  Here, when the polarization direction of the rotation target light is rotated by the polarization rotation element 40, the polarizing plate (incident side polarizing plate) provided on the light incident side of the liquid crystal panel 30 shields the rotation target light. It should be noted that this increases the color purity of each color component light.

  Of course, the incident-side polarizing plate is designed to transmit high-color purity component light.

  The cross dichroic prism 50 is a color combining unit that combines light emitted from the liquid crystal panel 30R, the liquid crystal panel 30G, and the liquid crystal panel 30B. The combined light combined by the cross dichroic prism 50 is guided to the projection lens unit 110.

  The illumination device 120 includes a plurality of lens groups (lens 60R, lens 60G, lens 60B, lens 61 to lens 63), a plurality of dichroic mirror groups (dichroic mirror 71 and dichroic mirror 72), and a plurality of reflection mirror groups (reflection). A mirror 81, a reflection mirror 82, and a reflection mirror 83).

  The lens 60R is a lens that collects the red component light R so that the light emitted from the liquid crystal panel 30R is irradiated onto the projection lens unit 110. Similarly, the lens 60G is a lens that condenses the green component light G so that the light emitted from the liquid crystal panel 30G is irradiated onto the projection lens unit 110. The lens 60B is a lens that condenses the blue component light B so that the light emitted from the liquid crystal panel 30B is irradiated onto the projection lens unit 110. The lenses 61 to 63 are relay lenses for adjusting the difference between the optical path length of the red component light R and the green component light G and the optical path length of the blue component light B.

  The dichroic mirror 71 is an optical element that separates the combined light including the green component light G and the blue component light B from the red component light R. Specifically, the dichroic mirror 71 reflects the combined light including the green component light G and the blue component light B and transmits the red component light R.

  The dichroic mirror 72 is an optical element that separates the green component light G and the blue component light B out of the combined light separated by the dichroic mirror 71. Specifically, the dichroic mirror 72 reflects the green component light G and transmits the blue component light B.

  The reflection mirror 81 is a mirror that reflects the red component light R separated by the dichroic mirror 71 and guides the red component light R to the liquid crystal panel 30R side.

  The reflection mirror 82 and the reflection mirror 83 are mirrors that reflect the blue component light B separated by the dichroic mirror 72 and guide the blue component light B toward the liquid crystal panel 30B.

(Wavelength band of each color component light)
Hereinafter, the wavelength band of each color component light according to the first embodiment will be described with reference to the drawings. FIG. 2 is a diagram illustrating wavelength bands of each color component light according to the first embodiment.

  As shown in FIG. 2, the red component light R has the longest wavelength band among the color component lights. On the other hand, the blue component light B has the shortest wavelength band among the color component lights. The green component light G has a wavelength band sandwiched between the wavelength band of the blue component light B and the wavelength band of the red component light R.

  Here, since the cutoff wavelength of each color separation unit is changed according to the incident angle of the color component light incident on each color separation unit (dichroic mirror 71 and dichroic mirror 72), the boundary between the wavelength bands of each color component light (Boundary region (1) and boundary region (2)) are provided in the vicinity of the center cutoff wavelength of each color separation unit.

On the other hand, as shown in FIG. 2, the light amount of each color component light decreases as it reaches the long wavelength side (or short wavelength side) with the peak wavelength having the maximum light amount as a boundary.

  Therefore, in a mode in which priority is given to the emitted light amount of the color component light (light amount priority mode), it is preferable to use all of the color component light separated by each color separation unit. On the other hand, in a mode in which the color purity of the color component light is prioritized (color purity priority mode), it is not preferable to use all of the color component light separated by each color separation unit.

  In the first embodiment, in the color purity priority mode, the polarization rotator 40 rotates only the polarization direction of the rotation target light, thereby narrowing the wavelength band of the color component light transmitted through the liquid crystal panel 30. This increases the color purity of the color component light.

  Specifically, the polarizing plate provided on the light incident side of the liquid crystal panel 30R blocks the rotation target light Rr whose polarization direction is rotated by the polarization rotation element 40R. Here, the rotation target light Rr is light having a shorter wavelength than the red high-color purity component light Rt.

  Further, the polarizing plate provided on the light incident side of the liquid crystal panel 30B blocks the rotation target light Br whose polarization direction is rotated by the polarization rotation element 40B. Here, the rotation target light Br is light having a longer wavelength than the blue high-color purity component light Bt.

  Further, the polarizing plate provided on the light incident side of the liquid crystal panel 30G shields the rotation target light Gr whose polarization direction is rotated by the polarization rotation element 40G. Here, the rotation target light Gr is either or both of light having a shorter wavelength than the green high-color purity component light Gt and light having a wavelength longer than the green high-color purity component light Gt. It is.

  It is possible to increase the color purity of the specific color component light by adjusting the cutoff wavelength of each color separation unit, but the color purity of the color other than the specific color component light is lowered. For example, when the cut-off wavelength of the dichroic mirror 71 is adjusted to the long wavelength side in order to increase the color purity of the red component light R, it should be noted that the color purity of the green component light G decreases.

(Example of cutoff wavelength)
In the prior art using three color component lights, it is assumed that the center cutoff wavelength of the dichroic mirror that separates the red component light R and the green component light G is 570 nm in order to increase the color purity of green. In this case, a cut filter for cutting light having a wavelength of 590 nm or less is provided on the optical path of the red component light R separated by the dichroic mirror in order to increase the red color purity. That is, the color component light (yellow component light Ye) having a wavelength band of 570 nm to 590 nm is cut.

  On the other hand, in the case (1) using four color component lights (that is, yellow component light Ye), the center cutoff wavelength of the dichroic mirror that separates the red component light R and the green component light G is It is provided on the longer wavelength side than the central cutoff wavelength according to the prior art (for example, 575 nm). On the other hand, the cut filter cuts light on a shorter wavelength side (for example, less than 585 nm) than the cut filter according to the prior art.

  That is, in case (1), yellow component light Ye having a wavelength band of about 570 nm to 575 nm is superimposed on green component light G, and yellow component light Ye having a wavelength band of about 585 nm to 590 nm is superimposed on red component light R. Is done.

  In the case (2) using the four color component lights (that is, the yellow component light Ye), the central cutoff wavelength of the dichroic mirror that separates the red component light R and the green component light G is the case (1). ) On the longer wavelength side than the central cutoff wavelength (for example, 580 nm). On the other hand, no cut filter is provided.

  That is, in case (2), yellow component light Ye having a wavelength band of about 570 nm to 580 nm is superimposed on green component light G, and yellow component light Ye having a wavelength band of about 580 nm to 590 nm is superimposed on red component light R. Is done.

  In the first embodiment, when it is necessary to increase the color purity of green, the polarization rotation element 40G rotates the rotation target light Gr to narrow the wavelength band that transmits the liquid crystal panel 30G. Similarly, when it is necessary to increase the color purity of red, the polarization rotator 40R rotates the rotation target light Rr to narrow the wavelength band transmitted through the liquid crystal panel 30R.

  Therefore, in the first embodiment, as the center cutoff wavelength of the dichroic mirror 72 that separates the red component light R and the green component light G, either the case (1) or the case (2) described above is adopted. Good.

(Configuration of polarization convolution element)
Hereinafter, the configuration of the polarization rotator according to the first embodiment will be described with reference to the drawings. FIG. 3 is a diagram for explaining the polarization rotator 40 according to the first embodiment. It should be noted that the polarization convolution element 40R, the polarization convolution element 40G, and the polarization convolution element 40B have the same configuration.

In FIG. 3, λ ₁ is high color purity component light, and λ ₂ is rotation target light. As shown in FIG. 3, in the state where the voltage is not applied to the polarization convolution element 40 (OFF state), the polarization direction of λ _{1 and} the polarization direction of λ ₂ are not rotated. On the other hand, in a state where the voltage is applied to the polarization rotator 40 (ON state), the polarization direction of λ ₁ is not rotated, but the polarization direction of λ ₂ is selectively rotated by 90 °.

  Hereinafter, the rotation of the rotation target light Rr will be described by taking the polarization rotation element 40R as an example. FIG. 4 is a view for explaining the polarization rotator 40R according to the first embodiment. In FIG. 4, the vertical axis indicates the ratio (transmittance) at which the red component light R (rotation target light Rr) passes through the polarization rotator 40R without being rotated when it enters the polarization rotator 40R. The horizontal axis indicates the wavelength of the red component light R. Therefore, in FIG. 4, it should be noted that the polarization direction of the red component light R (rotation target light Rr) is rotated as the transmittance is lower.

  As shown in FIG. 4, as the voltage applied to the polarization rotator 40R increases, the transmittance of the red component light R (that is, the rotation target light Rr) having a predetermined wavelength (for example, 600 nm) or less decreases. That is, as the voltage applied to the polarization rotation element 40R increases, the polarization direction of the rotation target light Rr is rotated.

  Next, the rotation of the rotation target light Gr will be described by taking the polarization rotation element 40G as an example. FIG. 5 is a view for explaining the polarization rotator 40G according to the first embodiment. In FIG. 5, the vertical axis indicates the ratio (transmittance) at which the green component light G (rotation target light Gr) is transmitted through the polarization rotator 40G without being rotated when it enters the polarization rotator 40G. The horizontal axis indicates the wavelength of the green component light G. Therefore, in FIG. 5, it should be noted that the polarization direction of the green component light G (rotation target light Gr) is rotated as the transmittance is lower.

  As shown in FIG. 5, as the voltage applied to the polarization rotator 40G increases, the transmittance of the green component light G (that is, the rotation target light Gr) having a predetermined wavelength (for example, 570 nm) or more decreases. Similarly, as the voltage applied to the polarization rotator 40G increases, the transmittance of the green component light G (that is, the rotation target light Gr) having a predetermined wavelength (for example, 520 nm) or less decreases. That is, as the voltage applied to the polarization rotator 40G increases, the polarization direction of the rotation target light Gr is rotated.

(Color reproduction range)
Hereinafter, the color reproduction range according to the first embodiment will be described with reference to the drawings. FIG. 6 is a diagram for explaining the color reproduction range according to the first embodiment.

As shown in FIG. 6, in the light quantity priority mode, light that reaches each polarization rotator (polarization rotator 40R, polarization rotator 40G, and polarization rotator 40B) out of the color component light separated by the color separation unit. Since it is used, the color purity of each color component light is lowered. Therefore, in the light quantity priority mode, the color reproduction range is a range indicated by R ₁ , G ₁ and B ₁ .

On the other hand, in the color purity priority mode, only a part of the color component light (high color purity component light) separated by the color separation unit is used, so that the color purity of each color component light is improved. Therefore, in the color purity priority mode, the color reproduction range is a range indicated by R ₂ , G ₂ and B ₂ .

As described above, the color reproduction range (R ₂ , G ₂ and B ₂ ) in the color purity priority mode is wider than the color reproduction range (R ₁ , G ₁ and B ₁ ) in the light amount priority mode.

(Configuration of control unit)
Hereinafter, the configuration of the control unit according to the first embodiment will be described with reference to the drawings. FIG. 7 is a block diagram illustrating a configuration of the control unit 300 according to the first embodiment.

  As illustrated in FIG. 7, the control unit 300 includes an input signal reception unit 310, a color purity calculation unit 320, a modulation amount control unit 330, and a rotation amount control unit 340.

  The input signal receiving unit 310 receives a video input signal including a red input signal Rin, a green input signal Gin, and a blue input signal Bin. Specifically, the input signal receiving unit 310 receives a video input signal from a device such as a DVD playback device or a TV tuner.

  The color purity calculation unit 320 calculates the color purity corresponding to the red input signal Rin, the green input signal Gin, and the blue input signal Bin based on the video input signal. Subsequently, the color purity calculation unit 320 instructs the modulation amount control unit 330 to control the modulation amount of each liquid crystal panel 30 while adjusting the light quantity and color purity of each color component light, and the rotation of each polarization rotator 40. Is instructed to the rotation amount control unit 340.

  For example, in the color purity priority mode, the color purity calculation unit 320 instructs the rotation amount control unit 340 to rotate the rotation target light. In addition, the color purity calculation unit 320 instructs the modulation amount control unit 330 to control the modulation amount after adding correction that compensates for a decrease in the amount of light due to the rotation of the rotation target light to the video input signal.

  On the other hand, in the light amount priority mode, the color purity calculation unit 320 instructs the rotation amount control unit 340 not to rotate the rotation target light. In addition, the color purity calculation unit 320 instructs the modulation amount control unit 330 to control the modulation amount after adding correction for further increasing the light amount to the video input signal.

  Here, the color purity priority mode and the light quantity priority mode may be switched by the user as in the prior art.

  Further, the color purity priority mode and the light amount priority mode may be switched for each color in accordance with the color purity of each color corresponding to the video input signal.

For example, when the color purity corresponding to the red input signal Rin is equal to or higher than a predetermined color purity (T _R ), the polarization direction of the rotation target light Rr may be rotated (color purity priority mode). On the other hand, when the color purity corresponding to the red input signal Rin is less than the predetermined color purity (T _R ), it is not necessary to rotate the polarization direction of the rotation target light Rr (light quantity priority mode).

Similarly, when the color purity corresponding to the green input signal Gin is equal to or higher than a predetermined color purity (T _G ), the polarization direction of the rotation target light Gr may be rotated (color purity priority mode). On the other hand, when the color purity corresponding to the green input signal Gin is less than the predetermined color purity (T _G ), it is not necessary to rotate the polarization direction of the rotation target light Gr (light quantity priority mode).

When the color purity corresponding to the blue input signal Bin is equal to or higher than the predetermined color purity (T _B ), the polarization direction of the rotation target light Br may be rotated (color purity priority mode). On the other hand, when the color purity corresponding to the blue input signal Bin is less than the predetermined color purity (T _B ), it is not necessary to rotate the polarization direction of the rotation target light Br (light amount priority mode).

The predetermined color purity (T _R ), the predetermined color purity (T _G ), and the predetermined color purity (T _B ) are determined according to specifications required for the projection display apparatus 100, characteristics of each color, and the like. .

  In addition, when the polarization convolution element 40 is configured to be able to rotate the polarization direction of the light to be rotated within a range of 0 to 90 °, the color purity calculation unit 320 calculates the color calculated based on the video input signal. The rotation amount control unit 340 is instructed to rotate the rotation target light with a rotation amount corresponding to the purity. Accordingly, the color purity calculation unit 320 instructs the modulation amount control unit 330 to control the modulation amount after adding a correction according to the rotation amount of the rotation target light to the video input signal.

  The modulation amount control unit 330 controls the modulation amount of each liquid crystal panel 30 in units of pixels of the liquid crystal panel 30 in accordance with instructions from the color purity calculation unit 320.

  The rotation amount control unit 340 controls the rotation of each polarization rotation element 40 based on an instruction from the color purity calculation unit 320.

(Function and effect)
According to the projection display apparatus 100 according to the first embodiment, the polarization rotator 40 has the rotation target light (rotation target light Rr, rotation target light Gr) that is a part of the color component light incident on each liquid crystal panel 30. And the direction of polarization of the rotation target light Br) is rotated.

  Therefore, when the polarization rotator 40 does not rotate the rotation target light, the rotation target light is transmitted through each liquid crystal panel 30, and thus the light amount of the color component light emitted from each liquid crystal panel 30 increases (light amount priority mode). ). On the other hand, when the polarization convolution element 40 rotates the light to be rotated, the light to be rotated is shielded by the polarizing plate (polarizing plate provided on the light incident side) of each liquid crystal panel 30, Since it does not transmit, the color purity of the color component light emitted from each liquid crystal panel 30 is increased (color purity priority mode).

  In this way, by electrically controlling the polarization rotator 40, the illumination device 120 is compared with the prior art in which the dichroic filter must be mechanically moved in order to switch between the light amount priority mode and the color purity priority mode. In addition, the occurrence of a failure of the projection display apparatus 100 is suppressed.

  According to the projection display apparatus 100 according to the first embodiment, the light to be rotated (the light to be rotated Rr, the light to be rotated Gr, and the light to be rotated Br) is a mode in which priority is given to the color purity of the color component light. The liquid crystal panel 30 has a wavelength band outside the wavelength band of the high color purity component light to be modulated.

  Therefore, in the color purity priority mode, the color purity of the color component light can be increased according to the specifications required for the projection display apparatus 100.

  According to the projection display apparatus 100 according to the first embodiment, the control unit 300 (rotation amount control unit 340) rotates the polarization rotation elements 40 according to the color purity calculated based on the video input signal. Control the amount. Therefore, it is possible to switch to an appropriate mode according to the type of video.

[Second Embodiment]
The second embodiment will be described below with reference to the drawings. In the following, differences between the first embodiment and the second embodiment described above will be mainly described.

  Specifically, in the first embodiment described above, the polarization rotator 40R, the polarization rotator 40G, and the polarization rotator 40B are provided on the light incident side of the liquid crystal panel 30R, the liquid crystal panel 30G, and the liquid crystal panel 30B, respectively. . On the other hand, in the second embodiment, a polarization rotator 40X is provided instead of the polarization rotator 40R and the polarization rotator 40G.

  Here, the polarization convolution element 40X is provided on the optical path of the combined light including the red component light R and the green component light G, and has a convolution having a wavelength band near the boundary between the red component light R and the green component light G. It is configured to be able to rotate the polarization direction of the target light.

(Configuration of projection display device)
Hereinafter, the configuration of the projection display apparatus according to the second embodiment will be described with reference to the drawings. FIG. 8 is a diagram illustrating a configuration of the projection display apparatus 100 according to the second embodiment.

  As shown in FIG. 8, the illuminating device 120 includes a polarization rotator 40X instead of the polarization rotator 40R and the polarization rotator 40G. In addition, the illuminating device 120 replaces the lenses 61 to 63 with a lens 64 to a lens 66 (for adjusting the difference between the optical path length of the green component light G and the blue component light B and the optical path length of the red component light R ( Relay lens).

  The polarization rotator 40X is provided on the optical path of the combined light (red component light R and green component light G) separated by the dichroic mirror 171 between the dichroic mirror 171 and the dichroic mirror 172. The polarization rotation element 40X rotates the polarization direction of rotation target light (hereinafter referred to as rotation target light Ye) that is a part of the combined light separated by the dichroic mirror 171.

  Here, the rotation target light Ye has a wavelength band near the boundary between the red component light R and the green component light G. That is, the polarization rotation element 40X is configured to be able to rotate the rotation target light Ye without rotating the polarization directions of the red high-color purity component light Rt and the green high-color purity component light Gt.

  Here, the polarization convolution element 40X is an optical element configured to be selectively switchable between a state where the polarization direction of the rotation target light Ye is not rotated and a state where the polarization direction of the rotation target light Ye is rotated 90 °. The polarization rotator 40X may be an optical element that rotates the polarization direction of the rotation target light Ye within a range of 0 ° to 90 °.

(Configuration of polarization convolution element)
Hereinafter, the configuration of the polarization convolution element according to the second embodiment will be described with reference to the drawings. FIG. 9 is a view for explaining the polarization rotator 40X according to the second embodiment. In FIG. 9, the vertical axis represents the ratio (transmittance) at which the combined light (rotation target light Ye) is transmitted through the polarization rotator 40X without being rotated when it enters the polarization rotator 40X. The horizontal axis indicates the wavelength of the synthesized light. Therefore, in FIG. 9, it should be noted that the polarization direction of the combined light (the rotation target light Ye) is rotated as the transmittance is lower.

  As shown in FIG. 9, in a state where the voltage is applied to the polarization convolution element 40X (ON state), the transmittance of the synthesized light (that is, the convolution target light Ye) having a predetermined wavelength (for example, 600 nm) or less decreases. Similarly, in a state where the voltage is applied to the polarization rotator 40X (ON state), the transmittance of the synthesized light (that is, the rotation target light Ye) having a predetermined wavelength (for example, 570 nm) or more decreases. That is, in a state in which a voltage is applied to the polarization rotator 40X (ON state), the rotation target light Ye (that is, the yellow component light Ye) having a wavelength band near the boundary between the red component light R and the green component light G. The polarization direction is rotated.

  In addition, the illumination device 120 includes a dichroic mirror 171, a dichroic mirror 172, a reflection mirror 181, a reflection mirror 182, and a reflection mirror 183 instead of the dichroic mirror 71, the dichroic mirror 72, the reflection mirror 81, the reflection mirror 82, and the reflection mirror 83. Have.

  The dichroic mirror 171 is an optical element that separates the combined light including the red component light R and the green component light G from the blue component light B. Specifically, the dichroic mirror 171 reflects the combined light including the red component light R and the green component light G and transmits the blue component light B.

  The dichroic mirror 172 is an optical element that separates the red component light R and the green component light G out of the combined light separated by the dichroic mirror 171. Specifically, the dichroic mirror 172 reflects the green component light G and transmits the red component light R.

  The reflection mirror 181 is a mirror that reflects the blue component light B separated by the dichroic mirror 171 and guides the blue component light B to the liquid crystal panel 30B side.

  The reflection mirror 182 and the reflection mirror 183 are mirrors that reflect the red component light R separated by the dichroic mirror 172 and guide the red component light R to the liquid crystal panel 30R side.

(Function and effect)
According to the projection display apparatus 100 according to the second embodiment, the polarization rotation element 40X is provided on the optical path of the combined light including the red component light R and the green component light G. The polarization rotation element 40X rotates the polarization direction of the rotation target light Ye (that is, the yellow component light Ye) having a wavelength band near the boundary between the red component light R and the green component light G.

  That is, even if the polarization rotator 40R and the polarization rotator 40G are not provided, the polarization rotator 40X can switch the light amount priority mode and the color purity priority mode for the red component light R and the green component light G.

  As described above, the number of optical elements provided in the illumination device 120 (or the projection display apparatus 100) can be reduced as compared with the first embodiment while obtaining the same effect as that of the first embodiment.

[Third Embodiment]
Hereinafter, a third embodiment will be described with reference to the drawings. In the third embodiment, differences between the first embodiment and the third embodiment will be mainly described.

  Specifically, in the third embodiment, the control unit 300 controls the amount of rotation in the polarization direction of the light to be rotated by the polarization rotation element 40.

(Rotation amount control example 1)
The color purity calculation unit 320 provided in the control unit 300 described above is based on the video input signal including the red input signal Rin, the green input signal Gin, and the blue input signal Bin, and the saturation of a plurality of pixels constituting the entire frame. Is calculated. Subsequently, the color purity calculation unit 320 calculates an average value of saturation (hereinafter, average saturation (S _ave )) based on the saturation of a plurality of pixels.

The color purity calculation unit 320 determines the color reproduction range expansion rate (r) based on the average saturation (S _ave ). The color purity calculation unit 320 notifies the rotation amount control unit 340 of the color reproduction range expansion rate (r). The color reproduction range expansion rate (r) is a rate of expanding the color reproduction range with reference to the color reproduction range in the light amount priority mode.

Specifically, as shown in FIG. 10, the range of the color reproduction range expansion ratio (r) is “1” to “MAX”. When the average saturation (S _ave ) is in the range of 0 to the threshold Th ₁ , the color purity calculation unit 320 determines the color reproduction range expansion rate (r) to “1”. When the average saturation (S _ave ) is in the range from the threshold Th ₁ to the threshold Th ₂ , the color purity calculation unit 320 increases the color reproduction range expansion rate (r) as the average saturation (S _ave ) increases. Move closer to "MAX". When the average saturation (S _ave ) exceeds the threshold Th ₂ , the color purity calculation unit 320 determines the color reproduction range expansion rate (r) to “MAX”.

  Hereinafter, the definition of the above-described color reproduction range expansion ratio (r) will be described with reference to FIG. In FIG. 11, the color reproduction range is defined by the x axis and the y axis.

The range surrounded by R ₁ , G ₁ and B ₁ is the color reproduction range in the light amount priority mode. The coordinates of R ₁ , G ₁ and B ₁ are (R ₁ x, R ₁ y), (G ₁ x, G ₁ y) and (B ₁ x, B ₁ y), respectively. The range surrounded by R ₂ , G ₂ and B ₂ is the color reproduction range of the color purity priority mode. The coordinates of R ₂ , G ₂ and B ₂ are (R ₂ x, R ₂ y), (G ₂ x, G ₂ y) and (B ₂ x, B ₂ y), respectively. W is a white point having the lowest color temperature. The coordinates of W are (Wx, Wy).

Here, LR ₁ is a distance between (R ₁ x, R ₁ y) and (Wx, Wy). LR ₂ is the distance between (R ₂ x, R ₂ y) and (Wx, Wy). The maximum value “MAX” of the color reproduction range enlargement ratio (r) is defined by LR ₂ / LR ₁ . On the other hand, the minimum value “MIN” of the color reproduction range enlargement ratio (r) is defined by LR ₁ / LR ₁ = "1". That is, the range of the color reproduction range expansion ratio (r) is “1” to “MAX”.

  Note that the maximum value “MAX” of the color reproduction range expansion rate (r) may be defined according to the following assumptions.

LG ₁ : Distance between (G ₁ x, G ₁ y) and (Wx, Wy) LG ₂ : Distance between (G ₂ x, G ₂ y) and (Wx, Wy) LB ₁ :( Distance between B ₁ x, B ₁ y) and (Wx, Wy) LB ₂ : Distance between (B ₂ x, B ₂ y) and (Wx, Wy) Here, the color reproduction range enlargement ratio The maximum value “MAX” of (r) may be defined as an average value of LR ₂ / LR ₁ , LG ₂ / LG ₁ and LB ₂ / LB ₁ .

  The rotation amount control unit 340 controls the rotation amount in the polarization direction of the rotation target light by the polarization rotation element 40 based on the color reproduction range expansion ratio (r). The rotation amount control unit 340 rotates the polarization direction of the rotation target light as the color reproduction range expansion ratio (r) is closer to “MAX”. On the other hand, the rotation amount control unit 340 does not rotate the polarization direction of the rotation target light as the color reproduction range expansion ratio (r) is closer to “1”.

  In the rotation amount control example 1, the rotation amount control unit 340 uniformly controls the polarization rotation element 40R, the polarization rotation element 40G, and the polarization rotation element 40B. That is, the rotation amount control unit 340 uniformly controls the rotation amounts in the polarization direction of the rotation target light Rr, the rotation target light Gr, and the rotation target light Br.

(Rotation amount control example 2)
The color purity calculation unit 320 provided in the control unit 300 described above is based on the video input signal including the red input signal Rin, the green input signal Gin, and the blue input signal Bin, and the saturation of a plurality of pixels constituting the entire frame. Is calculated for each of a plurality of color ranges.

  Here, the color range corresponding to the liquid crystal panel 30R is a red range. The red range is a range having a hue near red. For example, the red range is a range having a hue from magenta to yellow.

  The color range corresponding to the liquid crystal panel 30G is the green range. The green range is a range having a hue near green. For example, the green range is a range having a hue from yellow to cyan.

  The color range corresponding to the liquid crystal panel 30B is a blue range. The blue range is a range having a hue near blue. For example, the blue range is a range having a hue from cyan to magenta.

  Hereinafter, the saturation of the pixels included in the red range is referred to as red saturation. Similarly, the saturation of pixels included in the green range and blue range is referred to as green saturation and blue saturation.

The color purity calculation unit 320 calculates an average value of red saturation (hereinafter, average red saturation (SR _ave )). Similarly, the color purity calculation unit 320 calculates an average value of green saturation (hereinafter, average green saturation (SG _ave )) and an average value of blue saturation (hereinafter, average blue saturation (SB _ave )). .

The color purity calculation unit 320 determines a color reproduction range expansion rate (Rr) for the polarization rotator 40R based on the average red saturation (SR _ave ). Similarly, the color purity calculation unit 320, based on the average green saturation (SG _ave ) and average blue saturation (SB _ave ), the color reproduction range expansion rate (Gr) for the polarization rotator 40G and the polarization rotator 40B. The color reproduction range enlargement ratio (Br) is determined. The color purity calculation unit 320 notifies the rotation amount control unit 340 of the color reproduction range expansion rate (Rr), the color reproduction range expansion rate (Gr), and the color reproduction range expansion rate (Br).

  Here, the method of determining the color reproduction range expansion rate is basically the same as in the control example 1 of the rotation amount (see FIG. 10). However, the method for determining the color reproduction range expansion rate (Rr), the color reproduction range expansion rate (Gr), and the color reproduction range expansion rate (Br) may be different from each other.

  The rotation amount control unit 340 controls the rotation amount in the polarization direction of the light to be rotated by the polarization rotation element 40R based on the color reproduction range expansion ratio (Rr). Similarly, the rotation amount control unit 340 rotates the rotation amount in the polarization direction of the light to be rotated by the polarization rotation element 40G and the polarization rotation element 40B based on the color reproduction range expansion rate (Gr) and the color reproduction range expansion rate (Br). To control. That is, the rotation amount control unit 340 individually controls the rotation amounts in the polarization direction of the rotation target light Rr, the rotation target light Gr, and the rotation target light Br.

(Rotation amount control example 3)
Here, it should be noted that the rotation amount control example 3 is based on the rotation amount control example 2.

  The color purity calculation unit 320 provided in the control unit 300 described above calculates the hues of a plurality of pixels constituting the entire frame based on the video input signal including the red input signal Rin, the green input signal Gin, and the blue input signal Bin. Calculate for each of a plurality of color ranges.

Subsequently, the color purity calculation unit 320 determines an adjustment coefficient (SR _c ) for adjusting the saturation of the pixels included in the red range for each pixel. Of course, the adjustment coefficient (SR _c ) is associated with the pixels included in the red range. Similarly, the color purity calculation unit 320 determines an adjustment coefficient (SG _c ) and an adjustment coefficient (SB _c ) for adjusting the saturation of the pixels included in the green range and the blue range for each pixel.

The color purity calculation unit 320 multiplies the saturation of the pixels included in the red range by the adjustment coefficient (SR _c ), and calculates the average value of the multiplication results as the average red saturation (SR _ave ). Similarly, the color purity calculation unit 320 multiplies the saturation of the pixels included in the green range and the blue range by the adjustment coefficient (SG _c ) and the adjustment coefficient (SB _c ), and then calculates the average value of the multiplication results as the average green saturation _{(SG ave)} and an average blue chroma is calculated as _{(SG ave).}

Here, the determination of the adjustment coefficient (SR _c ) will be described as an example with reference to FIG. As shown in FIG. 12, the adjustment coefficient (SR _c ) ranges from “0.5” to “1”. The color purity calculation unit 320 brings the adjustment coefficient (SR _c ) closer to “1” as the hue of the pixel included in the red range is closer to the red hue (R in FIG. 12). On the other hand, the color purity calculation unit 320 adjusts the adjustment coefficient (SR _c ) as the hue of a pixel included in the red range is closer to a magenta hue (Mg in FIG. 12) or a yellow hue (Ye in FIG. 12). Is close to "0.5".

As described above, since the average red saturation (SR _ave ) is calculated based on the saturation adjusted by the adjustment coefficient (SR _c ), the color reproduction range enlargement ratio increases as the number of pixels close to the red hue increases in the red range. (Rr) increases.

  The color reproduction range expansion rate (Gr) and the color reproduction range expansion rate (Br) are the same as the color reproduction range expansion rate (Rr). That is, as the number of pixels close to the green hue in the green range increases, the color reproduction range expansion rate (Gr) increases. Similarly, the color reproduction range enlargement ratio (Br) increases as the number of pixels close to the blue hue in the blue range increases.

(Rotation amount control example 4)
Here, it should be noted that the rotation amount control example 4 is based on the rotation amount control example 1.

  The color purity calculation unit 320 provided in the control unit 300 described above determines the luminance of a plurality of pixels constituting the entire frame based on the video input signal including the red input signal Rin, the green input signal Gin, and the blue input signal Bin. calculate.

Subsequently, the color purity calculation unit 320 determines an adjustment coefficient (S _c ) for adjusting the saturation of the pixels constituting the entire frame for each pixel. Needless to say, the adjustment coefficient (S _c ) is associated with the pixels constituting the entire frame.

The color purity calculation unit 320 calculates the average value of the multiplication results as the average saturation (S _ave ) after multiplying the saturation of the pixels constituting the entire frame by the adjustment coefficient (S _c ).

Specifically, as shown in FIG. 13, the color purity calculation unit 320 adjusts the adjustment coefficient (S _c ) when the luminance (L) of the pixels constituting the entire frame is in the range of 0 to the threshold Th _3. Is determined to be “0”. The color purity calculation unit 320 brings the adjustment coefficient (S _c ) closer to “1” when the luminance (L) of the pixels constituting the entire frame exceeds the threshold Th ₃ . The range of the adjustment coefficient (S _c ) is “0” to “1”.

As described above, since the average saturation (S _ave ) is calculated based on the saturation adjusted by the adjustment coefficient (S _c ), the color reproduction range expansion rate (r) increases as the number of pixels having higher luminance (L) increases. Becomes larger.

(Other control examples)
The rotation amount control example 2 and the rotation amount control example 4 may be combined. The rotation amount control example 3 and the rotation amount control example 4 may be combined.

In the rotation amount control example 1, the color reproduction range expansion ratio (r) is determined by the average saturation (S _ave ), but the control example is not limited to this. For example, instead of the average saturation (S _ave ), representative values such as the maximum luminance, the minimum luminance, and the variance value of a plurality of pixels constituting the frame may be used.

In the rotation amount control example 2, the color reproduction range enlargement ratio (Rr) and the color reproduction range enlargement ratio are determined by the average red saturation (SR _ave ), average green saturation (SG _ave ), and average blue saturation (SB _ave ). Although (Gr) and the color reproduction range enlargement ratio (Br) are determined, the control example is not limited to this. Instead of average red saturation (SR _ave ), average green saturation (SG _ave ), and average blue saturation (SB _ave ), the maximum luminance, the minimum luminance, and the variance of the pixels included in the red range, the green range, and the blue range A representative value such as a value may be used.

[Fourth Embodiment]
Hereinafter, a fourth embodiment will be described with reference to the drawings. In the third embodiment, differences between the first embodiment and the fourth embodiment will be mainly described.

  Specifically, in the fourth embodiment, the polarization rotator 40 is configured by a plurality of regions. The controller 300 controls the amount of rotation in the polarization direction of the light to be rotated by the polarization rotation element 40 for each of a plurality of regions.

  For example, as shown in FIG. 14, the liquid crystal panel 30 is composed of a plurality of regions. In the following, in order to identify the areas constituting the liquid crystal panel 30, each area is represented by P (x, y). Similarly, the polarization rotator 40 is composed of a plurality of regions. In the following, each region is represented by Q (x, y) in order to identify the region constituting the polarization rotator 40.

  The color purity calculation unit 320 provided in the control unit 300 described above calculates the saturation of a plurality of pixels corresponding to the region Q (x, y) based on the video input signal corresponding to the region Q (x, y). calculate. Here, the video input signal corresponding to the region Q (x, y) is a video input signal corresponding to the region P (x, y).

The color purity calculation unit 320 calculates the average saturation (S _ave ) for each region Q (x, y). Subsequently, the color purity calculation unit 320 determines the color reproduction range expansion rate (r) based on the average saturation (S _ave ). The color purity calculation unit 320 notifies the rotation amount control unit 340 of the color reproduction range expansion rate (r) determined for each region Q (x, y).

  The rotation amount control unit 340 determines the rotation amount in the polarization direction of the light to be rotated by the polarization rotation element 40 based on the color reproduction range expansion ratio (r) determined for each region Q (x, y). Control is performed every (x, y).

  Here, the fourth embodiment, that is, the process of controlling the rotation amount for each region Q (x, y) can be applied to any of the rotation amount control examples 1 to 4 and other control examples.

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

  For example, in the above-described embodiment, the description has been made on the assumption that the polarization convolution element 40 does not have resolution, but the present invention is not limited to this. The polarization rotator element 40 may be divided into a plurality of regions, and may be configured to be able to control the amount of rotation of the rotation target light for each of the plurality of regions. That is, the polarization rotator 40 may have a resolution.

  Thus, when the polarization rotator 40 has a resolution, the resolution of the polarization rotator 40 is preferably lower than the resolution of each liquid crystal panel 30. Accordingly, it is possible to suppress a decrease in the utilization efficiency of each color component light by the electrode provided on the polarization rotator 40 or the like.

  Of course, the amount of rotation of the rotation target light controlled for each of the plurality of areas is calculated based on the video input signal corresponding to each of the plurality of areas.

  As shown in the embodiment described above, the user may switch between the light amount priority mode and the color purity priority mode. In this case, a mode setting unit for the user to set the mode may be provided.

  For example, when the projection display apparatus 100 is used for data output, the light amount priority mode is selected. When the projection display apparatus 100 is used for home theater, the color purity priority mode is selected. Is done.

  Note that the mode may be automatically switched according to the application in which the projection display apparatus 100 is used.

  Further, switching between the light amount priority mode and the color purity priority mode may be performed according to the type of the input terminal of the video input signal. For example, when the input terminal of the video input signal is a D terminal or an HDMI terminal, the projection type video display apparatus 100 is likely to be used for home theater use, and therefore the color purity priority mode is automatically selected. Also good. On the other hand, when the input terminal of the video input signal is a DVI terminal or a VGA terminal, the projection-type video display device 100 is likely to be used for data output, so the light amount priority mode is automatically selected. May be.

  Further, switching between the light amount priority mode and the color purity priority mode may be performed according to the color purity of each color corresponding to the video input signal. That is, when the color purity of each color is equal to or higher than a predetermined color purity over a certain period, the mode may be automatically switched to the color purity priority mode. On the other hand, when the color purity of each color is less than a predetermined color purity over a certain period, the mode may be automatically switched to the light amount priority mode.

  In the first embodiment described above, the polarization rotator 40 is provided on the incident side of all the liquid crystal panels 30, but the present invention is not limited to this. Specifically, even if the polarization rotation element 40 is provided only on the incident side of one of the plurality of liquid crystal panels 30 according to the specifications required for the projection display apparatus 100. Good.

  In the second embodiment described above, the polarization rotator 40X is provided on the optical path of the combined light including the red component light R and the green component light G, but is not limited thereto. Specifically, the polarization rotator 40X may be provided on the optical path of the combined light including the green component light G and the blue component light B. In this case, the polarization rotator 40X is configured to rotate the polarization direction of the rotation target light (that is, the cyan component light Cy) having a wavelength band near the boundary between the green component light G and the blue component light B. The

  Although not particularly mentioned in the above-described embodiment, the projection display apparatus 100 may include an illuminance sensor that detects the illuminance around the projection display apparatus 100. The rotation amount control unit 340 controls the rotation of each polarization rotation element 40 according to the ambient illuminance detected by the illuminance sensor. For example, when the peripheral illuminance detected by the illuminance sensor is equal to or greater than a predetermined illuminance, the rotation amount control unit 340 controls each polarization rotator 40 so as not to rotate the polarization direction of the polarization target light (light amount priority mode). . On the other hand, when the peripheral illuminance detected by the illuminance sensor is less than the predetermined illuminance, the rotation amount control unit 340 controls each polarization rotation element 40 to rotate the polarization direction of the polarization target light (color purity priority). mode).

  Although not particularly mentioned in the above-described embodiment, the polarization direction of each color component light emitted from the light source 10 may be aligned with S-polarized light or P-polarized light.

  Although not particularly mentioned in the above-described embodiment, the lighting device 120 uses the fourth color light (yellow component light Ye and cyan component light Cy) in addition to the red component light R, the green component light G, and the blue component light B. May be.

1 is a diagram illustrating a configuration of a projection display apparatus 100 according to a first embodiment. It is a figure which shows the wavelength band of each color component light which concerns on 1st Embodiment. It is a figure for demonstrating the polarization | polarized-light convolution element 40 which concerns on 1st Embodiment. It is a figure for demonstrating the polarization | polarized-light convolution element 40R which concerns on 1st Embodiment. It is a figure for demonstrating the polarization | polarized-light convolution element 40G which concerns on 1st Embodiment. It is a figure which shows an example of the color reproduction range which concerns on 1st Embodiment. It is a block diagram which shows the structure of the control part 300 which concerns on 1st Embodiment. It is a figure which shows the structure of the projection type video display apparatus 100 concerning 2nd Embodiment. It is a figure for demonstrating the polarization | polarized-light convolution element 40X which concerns on 2nd Embodiment. It is a figure for demonstrating the example of control of the amount of rotations concerning 3rd Embodiment. It is a figure for demonstrating the example of control of the amount of rotations concerning 3rd Embodiment. It is a figure for demonstrating the example of control of the amount of rotations concerning 3rd Embodiment. It is a figure for demonstrating the example of control of the amount of rotations concerning 3rd Embodiment. It is a figure for demonstrating the example of control of the amount of rotations concerning 4th Embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Light source, 30 ... Liquid crystal panel, 40 ... Polarization convolution element, 50 ... Cross dichroic prism, 60 ... Lens, 61-66 ... Lens, 71-72 ... Dichroic Mirrors 81 to 83... Reflection mirrors 100... Projection-type image display device 110... Projection lens unit 120... Illumination device 171 to 172 ... Dichroic mirrors 181 to 183. Reflection mirror, 300 ... control unit, 310 ... input signal reception unit, 320 ... color purity calculation unit, 330 ... modulation amount control unit, 340 ... rotation amount control unit

Claims (11)

A color separation unit that separates white light emitted from a white light source into a plurality of color component lights;
A lighting device comprising: a red component light, a green component light, and a blue component light , each of which modulates red component light, green component light, and blue component light separated by the color separation unit;
A polarization rotator provided on the light incident side of the light modulation element for the red component light, the green component light and the blue component light ,
The polarization rotation element, with swirling the polarization direction of said turning subject light by that is once transmitted rotation object radiation which is part of the color component light to be guided before Symbol light modulator,
It said turning subject light, among the pre-Symbol light color component light to be guided to the modulation device, having a waveband outside the color purity component light is color component light having a wavelength band monochromatic color purity is high A lighting device characterized by that.   The polarization rotator is configured to be switchable between a state in which the polarization direction of the rotation target light is rotated by 90 ° and a state in which the polarization direction of the rotation target light is not rotated. Lighting equipment.   The lighting device according to claim 1, wherein the polarization rotator rotates a polarization direction of the rotation target light within a range of 0 ° to 90 °. 4. The apparatus according to claim 3 , further comprising a control unit that controls a rotation amount of the rotation target light in a polarization direction by the polarization rotation element in accordance with a video input signal used for modulation amount control of the plurality of light modulation elements. The lighting device described in 1. The control unit calculates the saturation of a pixel based on the video input signal, and controls the amount of rotation in the polarization direction of the rotation target light by the polarization rotation element based on the saturation. The lighting device according to claim 4 . The polarization rotator is a plurality of polarization rotators corresponding to each of the plurality of light modulation elements,
The control unit calculates saturation for each of a plurality of hue ranges corresponding to each of the plurality of light modulation elements based on the video input signal, and sets the saturation calculated for each of the plurality of hue ranges. 5. The illumination device according to claim 4 , wherein a rotation amount in a polarization direction of the rotation target light by the plurality of polarization rotation elements corresponding to each of the plurality of hue ranges is controlled based on the rotation amount. The control unit calculates a hue for each of a plurality of hue ranges corresponding to each of the plurality of light modulation elements based on the video input signal, and based on the hue calculated for each of the plurality of hue ranges, The lighting device according to claim 6 , wherein a rotation amount in a polarization direction of the rotation target light by the polarization rotation element is adjusted. The control unit calculates a luminance of a pixel based on the video input signal, and adjusts a rotation amount in a polarization direction of the rotation target light by the polarization rotation element based on the luminance. The lighting device according to claim 5 . The polarization rotator element is composed of a plurality of regions,
The control unit calculates saturation for each of the plurality of regions based on the video input signal corresponding to each of the plurality of regions, and based on the saturation calculated for each of the plurality of regions, The lighting device according to claim 4 , wherein a rotation amount in a polarization direction of the rotation target light by the polarization rotation element is controlled for each of the plurality of regions.   The illumination device according to claim 1, wherein a resolution of the polarization convolution element is lower than a resolution of the plurality of light modulation elements. A color separation unit that separates white light emitted from a white light source into a plurality of color component lights;
A red component light, a green component light, and a blue component light for modulating the red component light, the green component light, and the blue component light separated by the color separation unit;
A projection type image display apparatus comprising: a projection lens unit that projects each color component light modulated by the light modulation element for the red component light, the green component light, and the blue component light ,
A polarization rotator provided on the light incident side of the light modulation element for the red component light, the green component light and the blue component light ,
The polarization rotation element, with swirling the polarization direction of said turning subject light by that is once transmitted rotation object radiation which is part of the color component light to be guided before Symbol light modulator,
The rotation target light has a wavelength band outside the wavelength band of the high-color purity component light that is a color component light having a wavelength band in which the color purity of a single color is high among the color component light guided to the light modulation element. Projection-type image display device characterized by the above.

Images