JP2007127795A - Projection optical device, multiple-color light illuminating device and projection type image display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a projection optical device where dispersion angles are controlled per color light, to provide a multiple-color light illuminating device and a projection type image display device. <P>SOLUTION: A projection lens 3A has a color selectable diaphragm 31. The outermost circumferential ring region in the color selectable diaphragm 31 is made of a light shielding plate C of shielding light of all colors, and the central circular region is made of a opening region A of transmitting light of all colors. Then, the ring region between the opening region A and the light shielding region C is made of a color filter region B of transmitting only the light in a green wavelength band and shielding the light in a red wavelength band and a blue wavelength band. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a projection optical device, a multi-color light illumination device, and a projection display apparatus.

Conventionally, a projection display apparatus such as a liquid crystal projector is known. The full-color image light projected from the projection display apparatus is generated by, for example, red image light, green image light, and blue image light (see Patent Document 1).
JP 2005-516249 A

  By the way, for example, as the light has a shorter wavelength, an aperture aberration is more likely to occur. When such light is projected, the imaging performance is deteriorated.

  In view of the above circumstances, the present invention provides a projection optical device and a multi-color light illumination device that can control the dispersion angle for each color light. And the projection type video display apparatus using these projection optical apparatuses or a multi-color light illumination apparatus is provided.

  In order to solve the above-described problem, the projection optical apparatus of the present invention is a projection optical apparatus that magnifies and projects incident full-color image light using a lens and / or a curved mirror, and all of the plurality of color lights that become the full-color image light. A transparent central region, a color selection light shielding region located on the outer periphery side of the central region and functioning as a light shielding plate for one or a plurality of color lights of the plurality of color lights, and an outer periphery of the color selection light shielding region And a light-shielding region that shields all color lights (hereinafter referred to as a first projection optical device in this section).

  With the above configuration, the dispersion angle is controlled for each color light. That is, the F number of the projection system can be set for each color.

  In the first configuration, the color selection light blocking region may block blue light that is one color light of the full color video light. With such a configuration, it is possible to prevent as much as possible the occurrence of aperture aberration in blue light that is color light on the shortest wavelength side (hereinafter referred to as a second projection optical device in this section).

  In the first projection optical apparatus or the second projection optical apparatus, the color selection light-shielding area is located near the center area and is located on the outer peripheral side of the first area, which shields one color light. And a second region that shields one color light of the remaining two color lights and a color light shielded in the first region.

  A projection display apparatus according to the present invention includes any one of the above-described projection optical apparatuses, a single image display panel that gives the full-color image light to the projection optical apparatus, and each color light to the image display panel at the same time. And an illumination system that irradiates in a divided manner (hereinafter referred to as a first projection display apparatus in this section).

  The first projection display apparatus includes a solid light emitting element that emits light of each color, and the amount of power supplied to the solid light emitting element that emits color light blocked by the wavelength-selective aperture is set to the degree of light blocking. In view of the above, it may be increased or changed.

  The projection display apparatus of the present invention combines any one of the above-described projection optical apparatuses, three image display panels for each color light, and each color image light obtained through each image display panel. It is characterized by comprising combining means for supplying to the projection optical device and an illumination system for supplying each color light to each image display panel (hereinafter referred to as a second projection image display device in this section).

  In the second projection display apparatus, the illumination system separates white light into first color light, second color light, and third color light, and guides each color light to each image display panel. It may be configured.

  In the second projection display apparatus, the illumination system emits a first illumination device that emits a first color light, a second illumination device that emits a second color light, and a third color light. And a third lighting device. In such a projection display apparatus, the power supply amount to the illumination device that emits the color light blocked by the wavelength-selective diaphragm may be increased or changed in view of the degree of the light blocking.

  The projection display apparatus according to the present invention also includes a first video light generating means for generating a first color video light, a second video light generating means for generating a second color video light, and a third color light. Third image light generating means for generating two image lights using two image display panels, and a first composition for combining the image light of the first color and one of the image lights of the third color. Means, first projection means for projecting the combined image light emitted from the first combining means, and a second color for combining the second color image light and the third color image light. 2 combining means and second projecting means for projecting the composite image light emitted from the second combining means, at least one of the first projecting means and the second projecting means being the first projecting means. An optical device or a second projection optical device (hereinafter referred to as a third projection image table in this section). That the apparatus).

  The multi-color light illuminating device of the present invention includes a plurality of illuminating devices including a plurality of solid-state light sources that emit color light and a plurality of light-guiding devices that guide the color light from each solid-state light source to an illumination object. The color light illuminating device is characterized in that the degree of dispersion angle reduction in specific color light having a wavelength shorter than or different from that of certain color light is higher than the degree of dispersion angle reduction in the certain color light ( Hereinafter, this section is referred to as a first multi-color light illumination device).

  With the multi-color light illumination device having such a configuration, for example, it is possible to prevent as much as possible the occurrence of aperture aberration in blue light having a shorter wavelength than that of green light.

  According to another aspect of the present invention, there is provided a projection-type image display apparatus, wherein the first multi-color light illuminating device described above, the image display panel as the illumination object, and image light obtained through each image display panel in a specific direction. The image forming apparatus includes: a combining unit that guides and generates full-color image light; and a projection unit that projects the full-color image light.

  Further, the multi-color light illuminating device of the present invention includes each solid-state light source that emits each color light, an optical element that guides the color light from each solid-state light source in a specific direction by wavelength dependency, and the light emitted from the optical element as an object A multi-color light illuminating device comprising a tapered rod integrator as a light guiding means for guiding an object, wherein the tapered rod integrator has a wavelength shorter than a certain color light or a specific color light having a different wavelength. A tapered cylindrical surface that functions as a dichroic mirror surface is formed, and an entrance of the tapered cylindrical surface is formed smaller than a light incident surface of the tapered rod integrator. The degree of angle reduction is higher than the degree of dispersion angle reduction in the certain color light (hereinafter referred to as the first in this section). That multi-color illuminating device). Also in the multi-color light illuminating device having such a configuration, for example, it is possible to prevent an aperture aberration from occurring in blue light having a wavelength shorter than that of green light as much as possible.

  In addition, the projection display apparatus of the present invention includes the above-described second multi-color light illuminating device, a single image display panel as a pre-illumination object, and irradiating each color light to the image display panel simultaneously or in a time-sharing manner. As described above, it comprises means for controlling the second multi-color light illumination device and projection means for projecting full-color image light obtained by the single image display panel.

  According to the present invention, the dispersion angle is controlled for each color light. As a result, for example, it is possible to prevent the occurrence of aperture aberration in blue light as much as possible and to improve the imaging quality.

First Embodiment Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a diagram showing an optical system of a projection display apparatus. This projection display apparatus includes three illumination devices 51R, 51G, and 51B. Each lighting device 51 includes an LED (light emitting diode) 11, a taper type rod integrator 12 </ b> E, and a rectangular parallelepiped rod integrator 15.

  The LED 11 includes an LED chip 11a and a heat sink (heat radiating plate) 11b. The LED chip 11a in the illumination device 51R emits red light, the LED chip 11a in the illumination device 51G emits green light, and the LED chip 11a in the illumination device 51B emits blue light.

  Each color light emitted from each illuminating device 51 is transmitted through each color liquid crystal display panel 1R, 1G, 1B, thereby generating each color video light. Each color image light is combined by a cross dichroic prism 2 (which may be a cross dichroic mirror) to become full color image light. This full-color image light is projected by the projection lens 3A.

  As shown in FIGS. 2A and 2C, the projection lens 3A has a color selective diaphragm 31. As shown in FIG. The outermost ring area of the color selective diaphragm 31 is a light shielding plate C that blocks all colors of light, and the central circular area is an opening area A that transmits light of all colors. The ring region between the opening region A and the light shielding region C is a color filter region B that transmits only light in the green wavelength band and shields light in the red wavelength band and blue wavelength band. FIG. 2D shows a normal diaphragm 39 without color selectivity as a comparative example. The outermost ring area of the stop 39 is a light shielding plate Y that blocks all colors of light, and the central circular area is an opening area X that transmits light of all colors. The color selective diaphragm 31 is not limited to the one in which the respective regions are formed concentrically. For example, as shown in FIG. 2B, a type (cat's eye type) in which the regions A, B, and C are formed non-concentrically may be used. Each of the regions A, B, and C is not limited to a circle or an ellipse, and may have a polygonal shape.

  Further, as shown in FIG. 3A, a color selective stop 32 having four regions A, B1, B2, and C may be used in place of the color selective stop 31. The color filter region B1 of the color selective diaphragm 32 is located on the side close to the region A, transmits light in the green wavelength band and red wavelength band (G + R = Y (yellow)), and transmits light in the blue wavelength band (G + R = Y (yellow)). B) is shielded from light. The color filter region B2 of the color selective diaphragm 32 is located on the side close to the region C, transmits only the green wavelength band, and blocks light in the blue wavelength band and the red wavelength band. As shown in FIG. 3B, the color-selective diaphragm 32 is made of a glass group in which colored glass mixed with a substance having wavelength selectivity (absorption and reflection with respect to light of a certain wavelength) is partially arranged. Alternatively, as shown in FIG. 3C, a color film in which a substance having wavelength selectivity is mixed may be pasted on a transparent glass plate. The same applies to the color-selective diaphragm 31 described above. In addition, the size of each region can be arbitrarily changed by adopting a diaphragm blade type in which the diaphragm blades are made of colored glass or the like without being limited to the region fixed type. The wavelength is increased in the order of blue light, green light, and red light (though aperture aberration is more likely to occur as the wavelength is shorter), the degree of color stop (degree of light cut) is set to blue. The order is light, red light, and green light. This assumes the case where the light emission amount of the green LED is small. Therefore, when the amount of light emitted from the green LED is sufficient, it goes without saying that the degree of color stop (degree of light cut) may be the order of blue light, green light, and red light.

  FIG. 4 shows how the green video light and the blue video light are used. The red image light is the same as the blue image light. In the drawing, “with aperture” indicates the case where the aperture 39 of FIG. 2D is used, and “with color aperture” indicates the case where the color selective aperture 31 of FIG. 2A is used. ing. With the configuration using the aperture 39, the aperture aberration can be reduced in all color image light, so that light that degrades the imaging performance (light with a large dispersion angle) is cut. As a result, the quality of the projected image is improved, but the white luminance is reduced by the amount of light that reduces the imaging performance. In addition, if the configuration has no diaphragm, light that degrades the imaging performance in both the green image light and the blue image light is not cut, so that a decrease in white luminance can be avoided. However, the light that degrades the imaging performance in the blue image light is not cut (since it is not configured to reduce the aperture aberration in the blue image light), the imaging performance is degraded.

  On the other hand, if the color selective diaphragm 31 is used, the light that degrades the imaging performance in the blue image light is cut (because the aperture aberration can be reduced in the blue image light). The imaging performance is improved as compared with the configuration without an aperture, and since the green image light is not cut, a decrease in the luminance of the green light can be suppressed. Here, if the blue LED chip 11a is not driven at the maximum (maximum power supply), the amount of blue light is reduced by using the color selective diaphragm 31, and the supply current to the blue LED chip 11a is reduced. What is necessary is just to increase the luminous brightness by increasing it. Since the white balance can be realized by increasing the emission luminance of blue light as described above, the white luminance can be made equal to the white luminance in the above-described configuration without an aperture.

  The configuration using the color selective diaphragm 31 can be said to be a configuration for controlling the dispersion angle for each color image light (it can also be said that the F number of the projection lens is set for each color). Here, in the case of the above-described configuration example, the F number is reduced for green light, and bright image light is projected for green light. Of course, it is not limited to the structure which makes F number small about green light.

  FIG. 5 is an explanatory diagram showing a state in which the liquid crystal display panel 1 is divided into nine equal parts (length 3 × width 3). When the integrated light amount on the liquid crystal display panel 1 is not equal in each region, color unevenness is caused. The integrated light quantity on each region differs depending on the size of the light dispersion angle. For example, for green light, the dispersion angle when the integrated light amounts of the region (1) and the region (5) are equal is a certain dispersion angle θ1, as shown in FIG. For red light, as shown in FIG. 6B, the dispersion angle when the integrated light amounts of the region (1) and the region (5) are equal is a certain dispersion angle θ2 (θ1> θ2). Become. Therefore, if the diaphragm 39 cuts light having a dispersion angle θ2 or more, the accumulated amount of green light will be different in each region. On the other hand, if the color selective diaphragms 31 and 32 are used, the dispersion angle can be controlled for each color light. Therefore, the diaphragm for red light is made to correspond to the dispersion angle θ2, and the diaphragm for green light is dispersed. This can correspond to θ1, and the occurrence of color unevenness can be suppressed.

Second Embodiment FIG. 7A is an explanatory view showing a three-plate projection display apparatus having a lamp light source 67. The lamp light source 67 includes, for example, an ultra high pressure mercury lamp (UHP). White light emitted from the lamp light source 67 is guided to the first dichroic mirror 68 through a light integrator (for example, a rod integrator, a fly-eye lens pair, etc.) not shown. The first dichroic mirror 68 transmits light in the red wavelength band and reflects light in the cyan (green + blue) wavelength band. The light in the red wavelength band that has passed through the first dichroic mirror 68 is reflected by the reflection mirror 69 to change the optical path. The red light reflected by the reflection mirror 69 passes through a condenser lens 70 and is transmitted through a transmissive liquid crystal display panel 81 for red light, thereby being optically modulated. On the other hand, the light in the cyan wavelength band reflected by the first dichroic mirror 68 is guided to the second dichroic mirror 71.

  The second dichroic mirror 71 transmits light in the blue wavelength band and reflects light in the green wavelength band. The light in the green wavelength band reflected by the second dichroic mirror 71 is guided to the transmissive liquid crystal display panel 82 for green light through the condenser lens 72, and is modulated by being transmitted therethrough. The light in the blue wavelength band transmitted through the second dichroic mirror 71 is guided to the transmissive liquid crystal display panel 83 for blue light through the reflection mirrors 74 and 76, the relay lenses 73 and 75, and the condenser lens 77. The light is modulated by passing through this.

  Each of the liquid crystal display panels 81, 82, 83 includes a panel portion 81b formed by sealing liquid crystal between an incident side polarizing plate 81a, 82a, 83a and a pair of glass substrates (with pixel electrodes and alignment films formed). 82b, 83b and output side polarizing plates 81c, 82c, 83c. The modulated light (each color video light) modulated by passing through the liquid crystal display panels 81, 82, 83 is synthesized by the cross dichroic prism 78 to become color video light. This color image light is enlarged and projected by the projection lens 3B, and is projected and displayed on a screen (not shown).

  The projection lens 3 </ b> B includes a color selective diaphragm 33. As shown in FIG. 7B, the color selective diaphragm 33 has a central circular region that transmits red light (R), green light (G), and blue light (B), and around the central circular region. The existing first peripheral ring region transmits red light and green light (blue light is blocked), the second peripheral ring region existing around the first peripheral ring region transmits only red light, and the second peripheral region The third peripheral ring region existing around the ring region blocks all color light.

  Here, for example, the ultra high pressure mercury lamp includes a relatively large amount of blue light component and then a large amount of green light component in the emitted light. Aperture aberration is likely to occur in light on the short wavelength side. The color-selective diaphragm 33 of the projection lens 3B is the one that most restricts blue light, and then the green light (the degree of diaphragm is B> G> R). Can be represented). As described above, when the color selective diaphragm 33 is used, control is performed to reduce the dispersion angle most for blue light, which is light on the short wavelength side, and then the dispersion angle is reduced for green light. Control will be performed.

  Note that a configuration using the projection lens 3B can also be applied to a projection-type image display apparatus that projects white light from a white light source to a single image display panel without color separation.

  FIG. 8A shows the relationship between latitude (dispersion angle) θ and longitude Φ using an inverted conical shape (the position on the illumination object can be expressed in terms of latitude and longitude and the amount of light at that position can be considered). ing. Since the position is ring-shaped, the light amount at the ring-shaped position is referred to as light amount (longitude 360 ° conversion). Corresponding to this relationship, FIGS. 4B to 4D show graphs in which the dispersion angle θ is taken on the horizontal axis and the light amount (longitude of 360 ° converted) is taken on the vertical axis. If the diaphragm 39 is used, white light (all R, G, and B) is cut at a certain dispersion angle as shown in FIG. In the case of the color selective stop 32, as shown in FIG. 5C, when the color light is shown in order of increasing dispersion angle, the order is blue light, red light, and green light. If it is 33, as shown in FIG. 4D, when colored light is shown in order of increasing dispersion angle, the order is blue light, green light, and red light.

  Third Embodiment Hereinafter, a projection display apparatus according to a third embodiment of the present invention will be described with reference to FIGS.

  FIG. 9A is a diagram showing an optical system of a multi-projection lens type projection display apparatus according to this embodiment. This projection display apparatus has two projection systems. One projection system includes two illumination devices 51R and 51G-1, a liquid crystal display panel 1R, a liquid crystal display panel 1G-1, a dichroic prism (may be a dichroic mirror) 2RG, and a projection lens 3C. Another projection system includes two illumination devices 51B and 51G-2, a liquid crystal display panel 1B, a liquid crystal display panel 1G-2, a dichroic prism (may be a dichroic mirror) 2BG, and a projection lens 3D.

  Each illuminating device 51 includes an LED (light emitting diode) 11, a tapered rod integrator 12, a polarization conversion device 13, and a rectangular parallelepiped rod integrator 15.

  The LED 11 includes an LED chip 11a and a heat sink (heat radiating plate) 11b. The LED chip 11a in the illumination device 51R emits red light, and the LED chip 11a in the illumination device 51G-1 and the illumination device 51G-2 emits green light (not necessarily in the same wavelength band), and the illumination device 51B. The LED chip 11a emits blue light.

  The tapered rod integrator 12 has a tapered shape in which the light exit surface is larger than the light incident surface, and reduces the dispersion angle distribution existing in the light emitted from the LED chip 11a. And an effect of making the illuminance distribution non-uniformity existing in the light emitted from the LED chip 11a uniform (light integration effect). The tapered rod integrator 12 is made of a transparent member (transparent glass or the like) or a hollow member whose inner surface is a mirror.

  The polarization conversion device 13 has a V-shaped dielectric multilayer film (polarization separation film) at a position facing the light exit surface of the rod integrator 12. S-polarized light reflected by one surface of the V-shaped dielectric multilayer film is reflected by the adjacent reflective surface (or dielectric multilayer film), and similarly, the V-shaped dielectric multilayer film The S-polarized light reflected by the other surface is reflected by the adjacent reflecting surface (or dielectric multilayer film). The P-polarized light transmitted through the dielectric multilayer film is converted into S-polarized light by a phase difference plate (1 / 2λ plate). Of course, the light can be aligned with P-polarized light.

  The rectangular parallelepiped rod integrator 15 is made of a transparent member (transparent glass or the like) or a hollow member whose inner surface is a mirror, and makes light illuminance distribution uniform on the light emitting end surface by reflecting light on the inner surface. The light emitting end face of the rod integrator 15 is, for example, rectangular.

  In one projection system, red image light is generated by the red light emitted from the illumination device 51R passing through the red liquid crystal display panel 1R, and the green light emitted from the illumination device 51G-1 is for green. The first green image light is generated by passing through the first liquid crystal display panel 1G-1. Similarly, in another projection system, the blue light emitted from the illuminating device 51B passes through the blue liquid crystal display panel 1B to generate blue image light, and the green light emitted from the illuminating device 51G-2. The second green image light is generated by the light passing through the second liquid crystal display panel 1G-2 for green.

  The red image light and the first green image light are combined by one dichroic prism 2RG and projected by one projection lens 3C. Similarly, the blue image light and the second green image light are combined by the other dichroic prism 2BG and projected by the other projection lens 3D. Both projection lenses 3 </ b> C and 3 </ b> D may be movably arranged so that their optical axes can be adjusted. Further, the optical axes of the projection lenses 3C and 3D are made parallel to each other, and the liquid crystal display panels 1 are arranged so that the centers thereof are somewhat shifted with respect to the optical axes of the projection lenses 3C and 3D. Each image light may be projected onto a screen (particularly, a transmissive screen for a rear projector) at a predetermined distance from 3C and 3D.

  The projection lens 3C may be provided with a diaphragm 39, for example. The projection lens 33D is provided with a color selective diaphragm 34 shown in FIG. The color-selective diaphragm 34 has a central circular region that transmits all color light, a first ring region located on the outer peripheral side thereof shields only blue light, and a second ring region located on the outer peripheral side of the first ring region. Blocks all color light. With this configuration, control is performed to reduce the dispersion angle for blue image light. If the blue light LED chip 11a is not driven at the maximum, the supply current to the blue light LED chip 11a may be increased to increase the blue light emission luminance. For example, when the LED emits pulses, the power supply amount may be changed including the pulse interval.

  Both panels are arranged so that the pixel positional relationship between the first liquid crystal display panel 1G-1 and the second liquid crystal display panel 1G-2 is interpolated with each other, and video signals matching the pixel relationship are displayed. You may make it supply to each liquid crystal display panel 1G-1 and 1G-2. According to this, the resolution about a green image can be raised. Further, the LEDs 11 in the two lighting devices 51G-1 and 51G-2 may be alternately lighted in a time division manner. A configuration without the polarization conversion device 13 may also be employed. On the other hand, the configuration including the polarization conversion device 13 can also be applied to the projection display apparatus of FIG.

  FIG. 10 is an explanatory view showing another configuration example of a multi-projection lens type projection display apparatus. The illumination device 51R and the illumination device 51B are disposed to face each other with the dichroic prism 2GR and the dichroic prism 2GB interposed therebetween.

  Red light from the illumination device 51R (red video light that has passed through the liquid crystal display panel 1R) is incident on one light incident surface of the dichroic prism 2GR, and blue light (from the illumination device 51B is incident on one light incident surface of the dichroic prism 2GB. Blue image light that has passed through the liquid crystal display panel 1B enters. A liquid crystal display panel 1G-1 is disposed on the other light incident surface of the dichroic prism 2GR, and a liquid crystal display panel 1G-2 is disposed on the other light incident surface of the dichroic prism 2GB. Has been.

  The illumination device 51G-3 includes an LED 11 that emits green light, a tapered rod integrator 12A, a rectangular parallelepiped rod integrator 15, and a polarization conversion device 16. The polarization conversion device 16 aligns light incident from the side surface via the rod integrator 15 with, for example, S-polarized light. The polarization conversion device 16 has a structure in which two polarization beam splitters are arranged, or one polarization beam splitter and a reflection member that reflects light transmitted through the polarization beam splitter. And it arrange | positions to S polarization | polarized-light light by providing the phase difference plate (1/2 (lambda) plate) 16a in the light emission side of the polarizing beam splitter or reflection member located in a back | latter stage side. A structure in which the retardation plate is disposed between two polarizing beam splitters or between one polarizing beam splitter and a reflecting member may be employed.

  The two polarization beam splitters or one polarization beam splitter and the reflecting member in the polarization conversion device 16 have substantially the same size as the dichroic prisms 2GR and 2GB. The S-polarized light emitted from the polarization converter 16 becomes green image light through the two liquid crystal display panels 1G-1 and 1G-2, and these green image lights are incident on the dichroic prisms 2GR and 2GB, respectively. . The dichroic prism 2GR reflects red image light, transmits green image light, and guides each color image light to the projection lens 3. The dichroic prism 2GB reflects blue image light, transmits green image light, and guides each color image light to the projection lens 3.

  FIG. 11 is an explanatory view showing another configuration example of a multi-projection lens type projection display apparatus. A difference from the projection display apparatus shown in FIG. 10 is that an illuminating device 51G-3 ′ is provided instead of the above-described illuminating device 51G-3. The illumination device 51G-3 separates the light incident from the side surface of the polarization conversion device 16, whereas the illumination device 51G-3 ′ used in this configuration separates the light incident from the back surface side of the polarization conversion device 16A. In addition, the S polarization direction is aligned. The polarization conversion device 16A includes a phase plate 16a on the light output side of the polarization beam splitter on the front stage side so that the light is aligned in the S polarization direction.

  FIG. 12 is an explanatory view showing another configuration example of a multi-projection lens type projection display apparatus. The difference from the projection display apparatus shown in FIG. 10 is that an illumination device 51G-4 is provided instead of the illumination device 51G-3. Although this illuminating device 51G-4 has a structure equivalent to the illuminating device 51G-1 including the polarization conversion device 13, it is arranged horizontally (parallel to the illuminating device 51B). The half mirror 17 is disposed to face the dichroic prism 2GB at an angle of 45 °, and the mirror 18 is disposed to face the dichroic prism 2GR at an angle of 45 °, so that the green light emitted from the illumination device 51G-4 is emitted. The light is separated and incident on the dichroic prisms 2GB and 2GR, respectively.

  FIG. 13 is an explanatory view showing another configuration example of a multi-projection lens type projection display apparatus. A difference from the projection display apparatus shown in FIG. 12 is that an illumination device 51G-4 ′ is provided instead of the illumination device 51G-4. The illuminating device 51G-4 ′ enters light from the right side of the half mirror 17, whereas the illuminating device 51G-4 ′ enters light from the back side of the half mirror 17. The illumination device 51G-4 ′ includes a polarization conversion device 13 ′ instead of the polarization conversion device 13. The polarization conversion device 13 ′ has the same configuration as the polarization conversion device 16. The green light emitted from the LED 11 is incident on the side surface of the polarization conversion device 13 ′ via the rod integrator 12, and is aligned with the S-polarized light by the polarization conversion device 13 ′.

  In the projection display apparatus shown in FIGS. 9 to 13, all the liquid crystal display panels 1 for each color are irradiated with S-polarized light. Here, the liquid crystal display panel includes a parallel type in which the light transmission axes of the incident side polarizing plate and the outgoing side polarizing plate are orthogonal to each other and a parallel type. By aligning the liquid crystal display panel 1 for each color in either type, the polarization direction of each color image light is aligned. Of course, the polarization directions of the respective color image lights may not be aligned. In this case, the phase plate in the polarization conversion device 16 and the phase plate in the polarization conversion device 13 ′ are unnecessary. Even if both types are mixed, the polarization direction of each color image light can be made uniform by setting the polarization direction of the emitted light in the illumination device to a predetermined polarization direction.

  Further, the multi-projection lens type projection display apparatus described above may include a polarization beam splitter instead of the dichroic prisms 2RG and 2BG. In this case, the first green video light and the second green video light are set to be S-polarized light. Red image light and blue image light are P-polarized light. As a result, the first green image light and the red image light are combined due to the polarization dependency, and the second green image light and the blue image light are combined due to the polarization dependency. It is also possible to align the polarization directions of all color image light in one direction by providing a narrow-band phase difference plate that converts the polarization direction of specific color light by 90 ° on the light incident side of the projection lenses 3C and 3D. It is.

  The multi-projection lens type projection display apparatus described above is configured to generate two green image lights on the assumption that the amount of green light is insufficient from the viewpoint of white balance. If the amount of color light is insufficient, the image light of the insufficient color light may be generated, and the characteristics of the color selective aperture may be changed accordingly. Further, in the two projection systems, a configuration in which a dichroic prism (or a dichroic mirror may be used) is used for color image light synthesis in one projection system, and a polarization beam splitter is used in color image light synthesis in the other projection system. In addition to these dichroic prisms (which may be dichroic mirrors) and polarizing beam splitters, if an optical element that combines two image lights is provided, a projection-type image display apparatus using such an optical element as a combining means is provided. Can be configured.

  Fourth Embodiment Hereinafter, a projection display apparatus according to a fourth embodiment of the present invention will be described with reference to FIGS. In the projection display apparatus according to the fourth embodiment, the configuration of an illumination optical system that emits certain color light is different from the configuration of another illumination optical system that emits certain color light.

  FIG. 14 is a diagram showing an optical system of the projection display apparatus of this embodiment. This projection display apparatus includes three illumination devices 51R, 51G, and 51B-1. Each color light emitted from each illuminating device 51 is transmitted through each color liquid crystal display panel 1R, 1G, 1B, thereby generating each color video light. Each color image light is combined by a cross dichroic prism 2 (which may be a cross dichroic mirror) to become color image light. This color image light is projected by the projection lens 3. Although the projection lens 3 is a projection lens that does not include a color selective diaphragm, it does not exclude the provision of the color selective diaphragm 31 and the like described above.

  Here, the illumination device 51B-1 has a cylindrical member (mirror bonding rod) 17 and a Fresnel lens 14 whose inner surfaces are mirror surfaces on the light incident side of the tapered rod integrator 12E. The cylindrical member 17 exists in the range from the periphery of the Fresnel lens 14 to the light incident surface side of the tapered rod integrator 12E. The illumination devices 51G and 51R are not provided with the Fresnel lens 14 and the cylindrical member 17.

  Blue light emitted with a high dispersion angle passes through the Fresnel lens 14 and is converted into light with a low dispersion angle. Of course, since the light incident on the surface other than the effective surface of the Fresnel lens 14 cannot be used effectively, there is a possibility that the light use efficiency is lowered. If the blue light LED chip 11a is not driven at a maximum, the supply current to the blue light LED chip 11a may be increased (including the aforementioned change in the amount of supplied power) as much as the light use efficiency is reduced. As shown in the figure, the Fresnel lens 14 may be surrounded by the cylindrical member 17, and in this case, the light utilization rate can be improved. Further, the annular zone of the Fresnel lens 14 may be processed into an oval shape in accordance with the shape of the LED 11. Further, not only the Fresnel lens 14 but also a meniscus lens or the like that can obtain the effect of reducing the dispersion angle may be used.

  The degree of dispersion angle reduction in specific color light (blue light) having a shorter wavelength than some other color light (for example, green light) is higher than the degree of dispersion angle reduction in the other color light (green light). Just do it. Therefore, it is sufficient that at least one such configuration is satisfied, and the red light illumination device 51R may have the same or substantially the same configuration as the blue light illumination device 51B. Similarly, the green light illumination device 51G may have the same or substantially the same configuration as the blue light illumination device 51B, and the red light illumination device 51R may have a different configuration. In general, lenses are often designed based on green light because of visibility, but there are other design methods. For example, there are cases where the aberration of red light is large or the lens is designed with reference to blue light, so the degree of dispersion angle reduction in specific color light having a shorter wavelength than that of certain color light is the degree of reduction of dispersion angle in the certain color light. The degree of dispersion angle reduction in specific color light having a wavelength different from that of certain color light may be higher than the degree of reduction of dispersion angle in the certain color light. The same applies to the configuration examples shown below. Also, a configuration in which the rectangular parallelepiped rod integrator 15 is omitted can be adopted. The taper-type rod integrator 12E and the rectangular parallelepiped rod integrator 15 are not limited to those made of a transparent body such as glass, but may have a hollow structure with an inner surface as a mirror surface. The tube member 17 may be omitted by bringing the Fresnel lens 14 close to the light incident surface of the tapered rod integrator 12E.

  Another configuration example is shown below. FIG. 15A is an enlarged view showing a part of the lighting device 51B-2 (rod integrator 15 is omitted), and FIG. 15B is an enlarged view showing a part of the lighting devices 51R and 51G (rod). Integrator 15 is omitted). The overall configuration of the projection display apparatus is the same as that of the projection display apparatus shown in FIG. The shape of the light exit surface of the tapered rod integrator 12A is the same as or substantially the same as the aspect ratio of the liquid crystal display panel 1 (in the figure, the lateral width is shown as c). The shape of the light incident surface of the tapered rod integrator 12E is the same as or substantially the same as the aspect ratio of the liquid crystal display panel 1.

  Here, when the lateral width of the light incident surface of the tapered rod integrator 12E in the illumination devices 51G and 51R is b and the lateral width of the light incident surface of the tapered rod integrator 12A in the illumination device 51B-2 is a, a <b. The relationship is established. Each taper type rod integrator has the same length. The blue light LED 11 ′ (B) has a smaller light emitting area than the other color light LEDs 11. Since the ratio of the exit end area and the entrance end area of the tapered rod integrator 12A to the blue light source is larger than the ratio of the exit end area and the entrance end area of the taper rod integrator 12E to the green light source and the red light source, a high dispersion angle. Conversion of light into low dispersion angle light. As a result, control is performed to reduce the dispersion angle for blue light, which is short-wavelength light that is likely to cause aperture aberration.

  A configuration in which the rectangular parallelepiped rod integrator 15 is omitted can also be adopted. The tapered rod integrators 12E and 12A and the rectangular parallelepiped rod integrator 15 are not limited to those made of a transparent body such as glass, but may have a hollow structure whose inner surface is a mirror surface.

  FIG. 16A is an explanatory view showing a projection display apparatus having another configuration. The overall configuration of the projection display apparatus is the same as that of the projection display apparatus shown in FIG. FIG. 16B is an explanatory diagram showing the illuminating device 51 </ b> B- 3 and the low dispersion angle effect brought about by the curved surface effect. The taper-type rod integrator 12B in the illumination device 51B-3 has a curved reflection region that is more convex than the inclined reflection surface in the other taper-type rod integrator 12E and the like. The tangent to the curved surface of the curved reflection region forms a larger angle with respect to the optical axis of the tapered rod integrator 12B as it is closer to the light incident surface, and forms a smaller angle with respect to the optical axis as it is farther from the light incident surface. Is. The tapered rod integrator 12B having such a curved reflection region can reduce the dispersion angle of blue light. A configuration in which the rectangular parallelepiped rod integrator 15 is omitted can also be adopted. The taper-type rod integrators 12E and 12B and the rectangular parallelepiped rod integrator 13 are not limited to those made of a transparent body such as glass, but may have a hollow structure with a mirror surface on the inner surface.

  FIG. 17A is an explanatory diagram showing a projection type video display apparatus having another configuration. The overall configuration of the projection display apparatus is the same as that of the projection display apparatus shown in FIG. FIG. 17B is an explanatory diagram showing the low dispersion angle reduction effect brought about by the illumination device 51B-4 and the lens effect. The light emitting end of the rectangular parallelepiped rod integrator 15A in the illumination device 51B-4 has a convex lens shape. With this convex lens shape, light with a high dispersion angle at the output end of the rod integrator is converted into light with a low dispersion angle. Note that the rectangular parallelepiped rod integrator 15A may be omitted, and a lens shape having a condensing function may be formed on the light exit surface of the tapered rod integrator 12E. Alternatively, as shown in FIG. 17C, a lens shape may be formed on the light exit surface of the tapered rod integrator, and a rectangular parallelepiped rod integrator may be provided on the light exit side. Further, as shown in FIG. 17D, a lens shape may be formed on the light incident side of the rectangular parallelepiped rod integrator. Also, rod integrators other than those for blue light may have a lens shape. And, for example, by making the curvature of the lens shape with respect to blue light smaller than the curvature of the lens shape with respect to other color light, the high dispersion angle light at the rod integrator exit end is converted into light with a low dispersion angle. The directivity of the emitted light effective component of the rod integrator becomes sharper than other wavelength regions (green and red), and the aperture aberration can be reduced. The lens shape is not limited to the convex lens shape, and may be a Fresnel lens shape. Further, the taper type rod integrator 12E is not limited to a transparent body such as glass, but may have a hollow structure whose inner surface is a mirror surface.

  FIG. 18A is an enlarged view showing a part of the lighting devices 51R and 51G (rod integrator 15 is omitted), and FIG. 18B is an enlarged view showing a part of the lighting device 51B-5 (rod). Integrator 15 is omitted). The overall configuration of the projection display apparatus is the same as that of the projection display apparatus of FIG. In this embodiment, the illuminating device 51B-5 that emits blue light, which is short-wavelength light that easily causes aperture aberration, includes a tapered rod integrator 12C that uses glass of a low refractive index medium. When the refractive index of the tapered rod integrator 12E is n1, and the refractive index of the tapered rod integrator 12C is n2, n2 <n1 is established. FIGS. 19 (a) and 19 (b) illustrate the effects of providing a low refractive index medium (n0 <n2 <n1). As shown in FIGS. 19A and 19B, light incident on a medium having a low refractive index has a smaller refraction angle than light incident on a medium having a high refractive index. Accordingly, the number of reflections of light with a high dispersion angle can be increased in the tapered rod integrator 12C, and conversion from light with a high dispersion angle to light with a low dispersion angle is facilitated. A configuration in which the rectangular parallelepiped rod integrator 15 is omitted can also be adopted. The rectangular parallelepiped rod integrator 15 is not limited to a transparent body such as glass, and a hollow structure having a mirror surface on the inner surface may be used.

  FIG. 20 is a diagram showing an optical system of a projection display apparatus having another configuration. This projection-type image display device may be a cross dichroic prism (cross dichroic mirror that guides the color light from the LEDs 90R, 90G, and 90B that emits each color light in a specific direction depending on the wavelength dependency, and each color light is specified by a structure other than these. 91 may be an optical element that guides in the direction). On the light exit side of the cross dichroic prism 91, a tapered rod integrator 93A is disposed. A rectangular parallelepiped rod integrator 94 is disposed on the light exit side of the taper type rod integrator 93A. The light emitted from the rectangular parallelepiped rod integrator 94 is guided by the lens 95 to the reflective display panel 96. The image light obtained by being reflected by the reflective display panel 96 is projected by the projection lens 97.

  The projection display apparatus having such a configuration emits each color light (red light, green light, and blue light) in a time division manner, and drives the display panel 96 with each color video signal in accordance with the time division timing. To do. Alternatively, each color light (red light, green light, and blue light) may always be emitted, and the display panel 96 may include a color filter. Of course, instead of the reflective display panel 96, a transmissive display panel may be used.

  As shown in FIG. 21, the tapered rod integrator 93A has a tapered cylindrical surface 93Aa that functions as a dichroic mirror surface for blue light. The entrance of the tapered cylindrical surface 93Aa is formed smaller than the light incident surface of the tapered rod integrator 93A, and the inclined surface (blue light reflecting surface) of the tapered cylindrical surface 93Aa is the inclined surface of the tapered rod integrator 93A ( The slope is steeper than other color light reflecting surfaces. Thereby, only the blue light has the same effect as using a tapered rod having a small incident end area (a steep inclination angle). Therefore, the aperture aberration is reduced for the blue image light.

  The taper-type rod integrator 93A, for example, forms a dichroic film (dielectric multilayer film) that reflects blue light and transmits other color light on the peripheral surface of a trapezoidal glass body, and has a cavity corresponding to the glass body. It is obtained by inserting it into a rectangular cylindrical glass body having Alternatively, the taper-type rod integrator 93A may be a hollow member in which a dichroic film (dielectric multilayer film) is formed on the inner surface of the rectangular tube-shaped glass body having the hollow portion.

  In such a single-plate projection display apparatus, a configuration in which a normal rod integrator having no dichroic film is used in place of the taper-type rod integrator 93A and the projection lens 97 has a color-selective diaphragm can be employed. .

  FIG. 22 is an explanatory view showing a taper-type rod integrator 93B and a rectangular parallelepiped rod integrator 94A. The tapered rod integrator 93B has a tapered cylindrical surface 93Ba that functions as a dichroic mirror surface for blue light. The entrance of the tapered cylindrical surface 93Ba is formed smaller than the light incident surface of the tapered rod integrator 93B. The rectangular parallelepiped rod integrator 94A is formed with a tapered cylindrical surface 94Aa in the form of extending the tapered cylindrical surface 93Ba.

  FIG. 23 is a diagram showing a projection display apparatus having another configuration. This projection display apparatus has the same configuration as that of the projection display apparatus of FIG. 20, but includes a normal taper rod integrator 93, and includes a light emitting side of the cross dichroic prism 91 and a taper rod integrator 93. A wavelength-selective diffractive element 92 that causes a low dispersion angle with respect to blue light is provided between the light incident surface and the diffractive element 92 realizes a low dispersion angle of blue light. Note that a rectangular rod integrator may be used instead of the tapered rod integrator 93. The rectangular parallelepiped rod integrator 94 may be omitted. The tapered rod integrator 93 and the rectangular parallelepiped rod integrator 94 may not be a transparent body such as glass but may have a hollow structure. As a wavelength-selective diffraction element, one disclosed in JP-A-2002-350625 is known.

  In the projection display apparatus shown in FIGS. 14 to 23, for example, as shown in FIGS. 24A and 24B, a polarization conversion device 40 or a polarization conversion device 41 may be provided. The polarization conversion device 40 aligns light incident from the side surface with S-polarized light. The polarization conversion device 40 has a structure in which two polarization beam splitters are arranged, or one polarization beam splitter and a reflection member that reflects light from the polarization beam splitter. A phase difference plate (1 / 2λ plate) is provided on either the light exit side of one polarization beam splitter or the light exit side of the reflecting member, and converts one polarized light into the other polarized light. To align the polarization direction. Of course, it can be aligned with P-polarized light. A structure in which a retardation plate is disposed between two polarizing beam splitters or between one polarizing beam splitter and a reflecting member may be employed. The polarization conversion device 41 has the same configuration as that of the polarization conversion device 13.

  FIG. 25A is a graph showing the relationship between the light dispersion angle and the amount of light in the multi-color light illuminating device in which the configuration of each illumination system is not different, and FIG. 25B shows the configuration of each illumination system of the present application. It is the graph which showed the relationship between the dispersion angle of light and the light quantity in the different multi-color light illuminating device. As can be seen from these comparisons, in the projection display apparatus (multi-color light illumination device) shown in FIGS. 14 to 23, it can be seen that the dispersion angle of blue light is reduced more than that of other color lights. That is, the dispersion angle can be controlled for each color light, and the occurrence of aperture aberration in the short wavelength color light can be prevented as much as possible.

  In the above-described projection display apparatus, a projection lens is shown as the projection optical apparatus. However, the projection lens is not limited to a curved mirror (not limited to a concave mirror, but a plurality of spherical and aspherical mirrors that are a combination of a concave mirror and a convex mirror. It is also possible to apply a color-selective stop in a projection optical apparatus having a structure including:

It is explanatory drawing which showed the projection type video display apparatus of embodiment of this invention. It is explanatory drawing of the color-selective aperture diaphragm with which the projection lens of FIG. 1 is provided. It is explanatory drawing which showed the other example of the color-selective diaphragm. It is explanatory drawing explaining the effect | action of a color-selective aperture_diaphragm | restriction. It is explanatory drawing which showed light quantity distribution on a video display panel. It is the graph which each showed the relationship between the dispersion angle in green light and red light, and an integrated light quantity. FIG. 4A is an explanatory diagram showing a projection display apparatus according to an embodiment of the present invention, and FIG. 4B is an explanatory diagram of a color selective aperture. It is explanatory drawing which showed the relationship between a dispersion angle, a light quantity, and the dispersion angle of the light cut. FIG. 4A is an explanatory diagram showing a projection display apparatus according to an embodiment of the present invention, and FIG. 4B is an explanatory diagram of a color selective aperture. It is explanatory drawing which showed the other example of the projection type video display apparatus of embodiment of this invention. It is explanatory drawing which showed the other example of the projection type video display apparatus of embodiment of this invention. It is explanatory drawing which showed the other example of the projection type video display apparatus of embodiment of this invention. It is explanatory drawing which showed the other example of the projection type video display apparatus of embodiment of this invention. It is explanatory drawing which showed the other example of the projection type video display apparatus (multiple color light illumination apparatus) of embodiment of this invention. It is explanatory drawing which showed the illumination system part in the other example of the projection type video display apparatus (multiple color light illuminating device) of embodiment of this invention. FIG. 4A is an explanatory view showing another example of the projection display apparatus (multi-color light illumination device) according to the embodiment of the present invention, and FIG. 4B shows a part of the blue illumination device. It is the enlarged view shown. FIG. 4A is an explanatory view showing another example of the projection display apparatus (multi-color light illumination device) according to the embodiment of the present invention, and FIG. 4B shows a part of the blue illumination device. FIGS. 3C and 3D are explanatory diagrams showing a configuration that can be used in place of the configuration of FIG. It is explanatory drawing which showed the illumination system part in the other example of the projection type video display apparatus (multiple color light illuminating device) of embodiment of this invention. FIGS. 4A and 4B are explanatory diagrams for explaining a difference in refraction angle due to a difference in refractive index. It is explanatory drawing which showed the other example of the projection type video display apparatus (multiple color light illumination apparatus) of embodiment of this invention. It is explanatory drawing which showed the detail of the rod integrator of FIG. It is explanatory drawing which showed the other example of the projection type video display apparatus (multiple color light illumination apparatus) of embodiment of this invention. It is explanatory drawing which showed the other example of the projection type video display apparatus (multiple color light illumination apparatus) of embodiment of this invention. It is a figure which shows other embodiment of this invention, Comprising: The same figure (a) (b) is explanatory drawing which showed the example of application of the polarization converter. FIG. 6A is a graph showing the relationship between the light dispersion angle and the amount of light in a multi-color light illuminating device in which the respective configurations are not different, and FIG. It is the graph which showed the relationship between the dispersion angle of the light in an apparatus, and the light quantity.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Liquid crystal display panel 2 Cross dichroic prism 3 Projection lens 3A, 3B, 3C, 3D Projection lens (with color selective aperture)
31, 32, 33, 34 Color selective aperture 11 LED
12, 12A, 12B, 12C, 12E Tapered rod integrator 13, 13A Rectangular rod integrator 51 Illumination device

Claims (14)

In a projection optical apparatus that magnifies and projects incident full-color image light with a lens and / or curved mirror, a central region that transmits all of the plurality of color lights that become the full-color image light, and an outer peripheral side of the central region, There is a color selection light shielding area that functions as a light shielding plate for one or a plurality of color lights, and a light shielding area that is located on the outer peripheral side of the color selection light shielding area and shields all the color lights. A projection optical apparatus comprising a wavelength-selective aperture. The projection optical apparatus according to claim 1, wherein the color selection light-shielding region shields blue light that is one color light of the full-color image light. 3. The projection optical apparatus according to claim 1, wherein the color selection light-shielding region is located near the central region and shields one color light, and on the outer peripheral side of the first region. A projection optical apparatus, comprising: one color light of the two remaining color lights and a second area that shields the color light blocked by the first area. A projection optical device according to any one of claims 1 to 3, a single image display panel that gives the full-color image light to the projection optical device, and each color light to the image display panel simultaneously or in a time-sharing manner. A projection-type image display device comprising: an illumination system for irradiating. 5. The projection display apparatus according to claim 4, further comprising: a solid-state light emitting element that emits each color light, wherein the amount of power supplied to the solid light-emitting element that emits the color light blocked by the wavelength-selective diaphragm is A projection display apparatus characterized by being increased or changed in view of the degree of light shielding. The projection optical apparatus according to any one of claims 1 to 3, three image display panels for each color light, and each color image light obtained through each image display panel, and the projection optical apparatus. A projection-type image display apparatus comprising: a combining unit that supplies light to the image display panel; and an illumination system that supplies each color light to each image display panel. 7. The projection display apparatus according to claim 6, wherein the illumination system separates white light into first-color light, second-color light, and third-color light, and each color light is transmitted to each video display panel. A projection-type image display device characterized by being configured to guide. 7. The projection display apparatus according to claim 6, wherein the illumination system includes a first illumination device that emits light of a first color, a second illumination device that emits light of a second color, and a third color device. And a third illumination device that emits light. 9. The projection display apparatus according to claim 8, wherein the power supply amount to the illumination device that emits the color light shielded by the wavelength selective diaphragm is increased or changed in view of the degree of the light shielding. Projection-type image display device. The first video light generating means for generating the first color video light, the second video light generating means for generating the second color video light, and the third color video light using two video display panels. Two third image light generating means for generating, first combining means for combining the first color image light and one of the third color image lights, and the first combining means are emitted from the first combining means. First projection means for projecting composite video light, second synthesis means for synthesizing the second color video light and the other one of the third color video light, and emission from the second synthesis means A projection optical apparatus according to claim 1, wherein at least one of the first projection means and the second projection means is a projection optical apparatus. Projection-type image display device characterized by the above. A multi-color light illuminating device comprising a plurality of solid-state light sources that emit colored light and a light guide means that guides the color light from each solid-state light source to an object to be illuminated. A multi-color light illuminating device characterized in that the degree of dispersion angle reduction in specific color light having a short wavelength or different wavelength is higher than the degree of dispersion angle reduction in the certain color light. 12. The multi-color light illuminating device according to claim 11, a video display panel as the illumination object, and a combining unit that guides video light obtained through each video display panel in a specific direction to generate full-color video light. And a projection means for projecting the full-color image light. Each solid light source that emits each color light, and an optical element that guides the color light from each solid light source in a specific direction by wavelength dependence, and a tapered type as a light guide means that guides the light emitted from this optical element to an illumination object A multi-color light illuminating device comprising a rod integrator, wherein the tapered rod integrator has a tapered cylindrical surface that functions as a dichroic mirror surface for specific color light having a wavelength shorter than or different from a certain color light The entrance of the tapered cylindrical surface is formed to be smaller than the light incident surface of the tapered rod integrator, so that the degree of dispersion angle reduction in the specific color light is reduced in the dispersion in the certain color light. A multi-color light illuminating device characterized by being higher than the degree of angle reduction. The multi-color light illuminating device according to claim 13, a single video display panel as the illumination object, and the multi-color light illuminating device are controlled so as to irradiate each color light to the video display panel simultaneously or in a time-sharing manner. And a projection means for projecting full-color image light obtained by the single image display panel.

Images