JP2013190514A - Projector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a projector capable of further increasing efficiency of light utilization.SOLUTION: A projector comprises: a first illuminating device; a first light modulating device for forming first image light; a second illuminating device; a second light modulating device for forming second image light; polarized light synthesizing means for synthesizing the first image light and the second image light; and a projection optical system for projecting the light synthesized by the polarized light synthesizing means. The first light modulating device is provided with a plurality of pixels including sub-pixels modulating first color light and sub-pixel modulating second color light different from the first color light. The second light modulating device is provided with a plurality of pixels including sub-pixels modulating third color light and sub-pixel modulating fourth color light different from the third color light.

Description

  The present invention relates to a projector.

  Conventionally, as described in Patent Document 1, an illumination device including a light source device that emits parallel light, a reflection-type light modulation device that modulates light from the illumination device according to image information, and an optical modulation device A projector including a projection optical system for projecting light from the projector is known. According to the conventional projector, it is possible to project an image according to image information using light from the illumination device.

  Further, as described in Patent Document 2, it is widely known that a light source device including a solid light source that generates excitation light and a fluorescent layer that generates fluorescence from excitation light is used as a light source device of a projector. . Such a light source device can be reduced in size and weight, and high brightness can be obtained as compared with the size. Therefore, the projector can be reduced in size and weight, and a projector capable of obtaining higher brightness than the size can be realized. Such a projector is a very small projector (so-called pico projector), and is suitable not only for use alone but also for being incorporated in other devices.

JP 2010-91927 A JP 2009-277516 A

  In the technical field of projectors, it is always required to further increase the light utilization efficiency. In particular, in a very small projector, it is difficult to increase the brightness due to problems (such as securing of space) caused by the extremely small size, and thus it is particularly important to increase the light use efficiency.

  Furthermore, in a very small projector, there are a problem due to the limitation of the input power and a problem of a decrease in light emission efficiency due to a temperature rise of the light source itself due to an increase in input power to the solid light source. Furthermore, there is a problem of securing a space necessary for cooling the light source.

  For example, the total amount of light may be higher if one half of the power is divided into two solid light sources than the case where too much power is applied to one solid state light source. Since it can be lowered, it is even more advantageous from the viewpoint of cooling. Therefore, in a very small projector such as a pico projector, a high-intensity projector with a small total input power, that is, a projector with high light utilization efficiency is desired rather than a projector with a small number of light sources.

  Accordingly, the present invention has been made in view of the above-described circumstances, and an object thereof is to provide a projector capable of further increasing light use efficiency.

  [1] A projector according to the present invention includes a first illumination device and first light modulation that forms first image light by modulating light emitted from the first illumination device according to image information. An apparatus, a second illumination device, a second light modulation device that forms second image light by modulating light emitted from the second illumination device according to image information, and the first And a projection optical system for projecting the light synthesized by the polarization synthesizing unit. The first light modulation device includes: A plurality of pixels including a sub-pixel that modulates the first color light and a sub-pixel that modulates a second color light different from the first color light, and the second light modulation device converts the first color light into the first color light. A pixel including a sub-pixel to be modulated and a sub-pixel to modulate the second color light; Characterized in that it comprises several.

  For this reason, according to the projector of the present invention, it is possible to reduce the power input to one lighting device by dividing the lighting device into two, and to reduce the light emission efficiency and increase the temperature of the light source as the input power increases. Can be suppressed. As a result, the light utilization efficiency can be further increased.

  Further, according to the projector of the present invention, the light source device including the solid light source that generates the excitation light and the fluorescent layer that generates the fluorescence from the excitation light is provided. It is possible. In addition, the projector can have a higher luminance than the size.

  [2] In the projector according to the aspect of the invention, the polarization combining unit includes a polarization combining film, and the first light modulation device and the second light modulation device are transmissive liquid crystal light modulation devices. The image light is mainly composed of a P-polarized component with respect to the polarization composition film, and the second image light is composed mainly of an S-polarization component with respect to the polarization composition film.

  By adopting such a configuration, the first image light is mainly a P-polarized component with respect to the polarization composition film and the second image light is mainly an S-polarization component with respect to the polarization composition film. The first image light and the second image light can be efficiently synthesized by using a polarization beam synthesis film that substantially reflects S-polarized light. Therefore, the projector can achieve high luminance with a simple configuration.

In addition, by using the transmission type light modulation device as described above, a space necessary for the reflected light path can be omitted when the reflection type light modulation device is used. Therefore, a smaller projector is possible.
Here, “transmission type” means that a light modulation device as a light modulation device such as a transmission type liquid crystal light modulation device or the like is a type that transmits light, and “reflection type” means This means that a light modulation device as a light modulation device, such as a reflective liquid crystal light modulation device, is a type that reflects light.

  [3] In the projector according to the aspect of the invention, the first illuminating device emits light mainly including one of a P-polarized component with respect to the polarization composition film and an S-polarization component with respect to the polarization composition film. The second illuminating device emits light mainly composed of the other of the P-polarized light component for the polarized light combining film and the S-polarized light component for the polarized light combining film.

  According to the projector of the present invention, since the first image light is mainly a P-polarized component with respect to the polarization composition film and the second image light is mainly an S-polarization component with respect to the polarization composition film, the P-polarization is substantially transmitted. By using a polarization combining film that substantially reflects S-polarized light, the first image light and the second image light can be efficiently combined.

  [4] In the projector according to the aspect of the invention, the first light modulation device and the second light modulation device may include a light modulation device having a color filter.

  With such a configuration, it is possible to project a color projection image with one light modulation device.

  [5] In the projector according to the aspect of the invention, the color filter may be a reflective dichroic filter.

With such a configuration, it is possible to reflect color light that is not allowed to pass during color separation, and it is possible to prevent overheating of the light modulation device due to absorption of color light.
In addition, with such a configuration, it is possible to reflect a part of the light in the wavelength band of the excitation light among the light rays reaching the color filter, and re-enter the fluorescent layer as the excitation light. Thus, the light utilization efficiency can be further increased.

  [6] In the projector according to the aspect of the invention, the pixel included in the first light modulation device may include a sub-pixel that modulates the first color light and a third color light different from the second color light, and a fourth pixel. A sub-pixel that modulates the first color light, a sub-pixel that modulates the second color light, a sub-pixel that modulates the third color light, and the fourth color light. The sub-pixels to be modulated are provided in a Bayer array.

  With such a configuration, it is possible to project a projected image with high apparent resolution.

  [7] In the projector of the present invention, the fourth color light is white light.

  By adopting such a configuration, the amount of white light increases as compared with a simple Bayer arrangement. Furthermore, it is possible to prevent the color temperature from being deteriorated due to the excessive green color.

  [8] In the projector according to the aspect of the invention, the first lighting device includes a first solid-state light source, and a first fluorescent layer that emits fluorescence when irradiated with excitation light emitted from the first solid-state light source. It is characterized by providing.

  By adopting such a configuration, it is possible to obtain white light with high light utilization efficiency with a simple configuration.

  [9] In the projector according to the aspect of the invention, the first solid-state light source and the first fluorescent layer may form a white light emitting diode.

  With such a configuration, it is possible to project a full color image with high luminance and high reliability. This is because white light emitting diodes generally generate white light with high brightness and high reliability, and a relatively high color temperature (close to sunlight).

  [10] In the projector according to the aspect of the invention, the first display device and the second display device may have an image for the right eye on one side and an image for the left eye on the other side. It is characterized by displaying.

  With such a configuration, 3D projection without deterioration in luminance is possible. In general, for 3D display, the left and right images are temporally switched, and the left and right images of the 3D glasses are cut with a liquid crystal shutter or the like so as to be synchronized with the respective images. For this reason, the left and right images are not displayed at the same time, resulting in a problem of reduced brightness. According to the configuration of the present invention, it is possible to project the left and right images at the same time, and thus the above-described problem of luminance reduction does not occur.

FIG. 2 is a plan view showing an optical system of the projector according to the embodiment. The expanded sectional view of the 1st white light emitting diode in an embodiment. The graph which shows the light emission intensity characteristic of the 1st solid state light source in embodiment, and the light emission intensity characteristic of fluorescent substance. The figure shown in order to demonstrate the 1st light source device in embodiment. FIG. 3 is an enlarged schematic diagram of a color filter in the first embodiment. FIG. 3 is an enlarged schematic diagram of a color filter having another configuration according to the first embodiment. FIG. 4 is a diagram illustrating a relative light intensity (relative light beam intensity) of light emitted from the projector according to the embodiment. FIG. 6 is a plan view illustrating an optical system of a projector according to a second embodiment. The figure which shows the light emission characteristic of a white light emitting diode.

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

[Embodiment 1]
FIG. 1 is a plan view showing an optical system of a projector 1000 according to the first embodiment. Note that the plurality of arrows shown in FIG. 1 roughly illustrate the flow of light. Also, the solid black arrow represents unpolarized light in which S-polarized light and P-polarized light are mixed, the two-dot chain arrow represents P-polarized light with respect to the polarization conversion element, and the dashed arrow represents S-polarized light with respect to the polarization conversion element. Represents light.

  Actually, the polarization direction is rotated by a light modulation device to be described later. Here, for the sake of convenience, the principle description and the display indicating the rotation are omitted for the sake of convenience.

  As shown in FIG. 1, the projector 1000 according to the embodiment includes a first illumination device 100R, a second illumination device 100L, a first light modulation device 200R, a second light modulation device 200L, and a polarization. A synthesizing unit 300 and a projection optical system 400 are provided. The projector 1000 projects a full color image using red light, green light, and blue light. Each of the first light modulation device 200R and the second light modulation device 200L is a transmissive liquid crystal light modulation device that forms a full-color image. The polarization combining unit 300 includes a polarization combining film 301.

  Note that in FIG. 1 and FIG. 4 describing the first lighting device 100R, an xyz orthogonal coordinate system is used. The first illumination optical axis 100Rax direction of the first illumination device 100R is parallel to the paper surface in FIG. 1, and the first illumination optical axis 100Rax direction is the z-axis direction. A direction parallel to the paper surface and perpendicular to the z-axis is defined as an x-axis direction, and a direction perpendicular to the paper surface and perpendicular to the z-axis is defined as a y-axis direction. For the second lighting device 100L, an x′y′z ′ orthogonal coordinate system is used. The second illumination optical axis 100Lax direction of the second illumination device 100L is parallel to the paper surface in FIG. 1, and the x ′ axis and the y ′ axis are defined in the same manner as in the first illumination device 100R.

The projector 1000 will be described later when viewed from at least one direction (for example, the direction shown in FIG. 1) among the directions perpendicular to the first illumination optical axis 100Rax and the second illumination optical axis 100Lax. An optical system from the first solid state light source 24R to the projection optical system 400 is disposed.
In the projector 1000, an optical system from a first solid-state light source 24R to be described later to the projection optical system 400 is illustrated when viewed from a direction perpendicular to the first illumination optical axis 100Rax and the second illumination optical axis 100Lax. ing.

  The first lighting device 100R includes a first light source device 10R and a first polarization conversion element 50R. The second illumination device 100L includes a second light source device 10L and a second polarization conversion element 50L. Each of the first lighting device 100R and the second lighting device 100L emits light including red light, green light, and blue light as illumination light (that is, light that can be used as white light).

The first light source device 10R is a light source device that emits parallel light, and includes a first white light emitting diode 20R and a first collimator optical system 30R.
The second light source device 10L is a light source device that emits parallel light, and includes a second white light emitting diode 20L and a second collimator optical system 30L.
The components of the first light source device 10R are the same as the components of the second light source device 10L. For the sake of convenience, reference numerals indicating constituent elements of the first light source device 10R are appended with an R suffix, and reference numerals indicating constituent elements of the second light source device 10L are appended with an L suffix.
Since the second light source device 10L is exactly the same as the first light source device 10R, the description of the second light source device 10L is omitted.

  FIG. 2 is an enlarged cross-sectional view of the first white light emitting diode 20R included in the first light source device 10R. Since the second white light emitting diode 20L is exactly the same as the first white light emitting diode 20R, description of the second white light emitting diode 20L is omitted.

  As shown in FIG. 2, the first white light emitting diode 20R is a Lambertian light emitting diode having a substrate 22R, a first solid state light source 24R, a first fluorescent layer 26R, and a first sealing member 28R. is there. The first white light emitting diode 20R emits light including red light, green light, and blue light. Note that the first white light emitting diode 20R includes lead wires and the like in addition to the above-described components, but illustration and description thereof are omitted. In the projector of the present invention, a plurality of white light emitting diodes may be used as the first white light emitting diode 20R.

  A first solid light source 24R, a first fluorescent layer 26R, and a first sealing member 28R that is transparent to visible light are mounted on the substrate 22R. Although detailed description is omitted, the substrate 22R has a function of mediating supply of power to the first solid light source 24R, a function of radiating heat generated by the first solid light source 24R, and the like.

  FIG. 3A is a graph showing the emission intensity characteristic of the first solid-state light source 24R, and FIG. 3B is a graph showing the emission intensity characteristic of the phosphor contained in the first fluorescent layer 26R. The vertical axis of the graph represents relative light emission intensity, and the light emission intensity at the wavelength where the light emission intensity is strongest is 1. The horizontal axis of the graph represents the wavelength.

  The first solid-state light source 24R is formed of a light emitting diode that generates blue light that serves as both excitation light and color light. As shown in FIG. 3A, the peak of the emission intensity of the first solid-state light source 24R is about 460 nm.

  The first fluorescent layer 26R generates fluorescence from part of the blue light from the first solid light source 24R. Specifically, fluorescence including red light (emission intensity peak: about 610 nm) and green light (emission intensity peak: about 550 nm) is generated from a part of the blue light (see FIG. 3B). .)

  For this reason, the first white light emitting diode 20R has light (that is, as white light) including blue light and fluorescence (red light and green light) that pass through the first fluorescent layer 26R without being involved in the generation of fluorescence. Light that can be used) is emitted.

The first fluorescent layer 26R is made of, for example, a layer containing a YAG phosphor. In addition, as the first fluorescent layer 26R, a fluorescent layer containing another fluorescent material (silicate fluorescent material, TAG fluorescent material, etc.) can also be used. Further, the first fluorescent layer 26R includes a phosphor that converts excitation light into red light (for example, CaAlSiN ₃ red phosphor) and a phosphor that converts excitation light into green (for example, β sialon green phosphor). It is also possible to use a fluorescent layer.

  Note that the blue light that passes through the first fluorescent layer 26R without being involved in the generation of fluorescence is scattered or reflected in the first fluorescent layer 26R, and thus the first light is distributed as light having substantially the same distribution characteristics as fluorescence. The white light emitting diode 20R is emitted.

  FIG. 4 is a diagram showing details of the first light source device 10R. FIG. 4A is a diagram illustrating a state in which light emitted from the first white light emitting diode 20R is collimated by the first collimator optical system 30R. In addition, the light ray in Fig.4 (a) does not represent a light beam density. FIG. 4B is a graph showing the relative light intensity (relative luminous flux intensity) of the light emitted from the first collimator optical system 30R. The vertical axis of FIG. 4B indicates the relative light intensity of the light emitted from the first collimator optical system 30R, and the light intensity on the optical axis is 1. The horizontal axis indicates the distance from the optical axis. The solid line graph in FIG. 4B shows the relative light intensity in the yz plane, and the broken line graph shows the relative light intensity in the xz plane. FIG. 4C is a diagram showing a relative light intensity distribution when the light emitted from the first collimator optical system 30R is viewed from the z-axis direction. A rectangle indicated by a broken line in FIG. 4C indicates the shape of the passage portion 42R included in the first polarization conversion element 50R described later. Although the passing portion 42R is not shown in FIG. 1, the light emitted from the first collimator optical system 30R passes through the passing portion 42R and travels into the first polarization conversion element 50R.

  The first collimator optical system 30R is an optical element that collimates the light from the first white light emitting diode 20R. As shown in FIGS. 1 and 4A, the first G1 lens 32R, It consists of a first G2 lens 35R. In the first collimator optical system 30R, as shown in FIG. 4A, the first G1 lens 32R is composed of a meniscus convex lens in which a spherical surface is formed on the entrance surface 31R and the exit surface 33R. The G2 lens 35R includes an aspherical biconvex lens in which an aspherical surface is formed on the incident surface 34R and the exit surface 36R. For this reason, the first collimator optical system 30R satisfies the condition that at least one of the plurality of surfaces of the two or more collimator lenses is an aspherical surface. As shown in FIGS. 4B and 4C, the first collimator optical system 30R emits light having a substantially uniform light flux density distribution.

  Since the second collimator optical system 30L is exactly the same as the first collimator optical system 30R, description of the second collimator optical system 30L is omitted.

  The shapes of the first G1 lens 32R and the first G2 lens are not limited to the above shapes. Further, the number of lenses constituting the first collimator optical system 30R may be one, or may be three or more. The same applies to the second collimator optical system 30L.

  The first polarization conversion element 50R is a polarization conversion element that converts the polarization of the light that has passed through the passage portion 42R. The passage portion 42R has a rectangular shape, and the center of the rectangular shape is the first illumination optical axis 100Rax. Further, the diagonal length L of the rectangular shape is in the range of 70% to 110% of the effective diameter of the first collimator optical system 30R, for example, about 85%.

  In the embodiment, the rectangular shape is configured such that the ratio of the length in the horizontal direction (x-axis direction) to the length in the vertical direction (y-axis direction) is 8: 9. In addition, the shape of the passage part in this invention is not limited to this, It can be set as the shape according to the structure of a projector.

  Since the passage part 42L (not shown) provided in the second polarization conversion element 50L is exactly the same as the passage part 42R, description of the passage part 42L is omitted.

  The first polarization conversion element 50R is a known polarization conversion element including a first polarization separation layer 51R, a first reflection layer 52R, and a first retardation plate 60R. The first polarization separation layer 51R is a polarized light polarized in the first polarization direction among the polarization components included in the light incident along the first illumination optical axis 100Rax (P-polarized light with respect to the first polarization separation layer 51R). ) Is transmitted, and the polarized light polarized in the second polarization direction (S-polarized light with respect to the first polarization separation layer 51R) is reflected in the direction perpendicular to the first illumination optical axis 100Rax. The first polarization direction and the second polarization direction make an angle of 90 ° with each other. The first reflective layer 52R reflects the S-polarized light reflected by the first polarization separation layer 51R in a direction parallel to the first illumination optical axis 100Rax. The first retardation plate 60R is provided at a position where the S-polarized light reflected by the first reflective layer 52R is incident, and converts the S-polarized light into P-polarized light.

  Note that the shape of the passage portion 42R and the shape of the range in which the first polarization conversion element 50R can convert light are the same shape.

  As shown in FIG. 1, the P-polarized light that passes through the first polarization separation layer 51R enters the first light modulation device 200R while maintaining its polarization state. On the other hand, the S-polarized light reflected by the first polarization separation layer 51R and further passing through the first retardation plate 60R is converted into P-polarized light and then enters the first light modulation device 200R. As described above, the first illumination device 100R emits light mainly including the P-polarized light component with respect to the polarization combining film 301.

  Since the first polarization conversion element 50R has the above-described configuration, as shown in FIG. 1, the width of the light beam that has passed through the first polarization conversion element 50R in the x-axis direction is the first polarization conversion element 50R. This is twice the width in the x-axis direction of the light beam before passing through. Since the ratio of the length in the horizontal direction to the length in the vertical direction is 8: 9, the luminous flux after passing through the first polarization conversion element 50R is 16: 9. Become.

  The second polarization conversion element 50L is a known polarization conversion element including a second polarization separation layer 51L, a second reflection layer 52L, and a second retardation plate 60L. The second polarization separation layer 51L is polarized light polarized in the first polarization direction among the polarization components included in the light incident along the second illumination optical axis 100Lax (P-polarized light with respect to the second polarization separation layer 51L). ), And the polarized light polarized in the second polarization direction (S-polarized light with respect to the second polarization separation layer 51L) is reflected in the direction perpendicular to the second illumination optical axis 100Lax. The second reflective layer 52L reflects the S-polarized light reflected by the second polarization separation layer 51L in a direction parallel to the second illumination optical axis 100Lax. The second retardation plate 60L is provided at a position where the P-polarized light transmitted through the second polarization separation layer 51L is incident, and converts the P-polarized light into S-polarized light.

  The P-polarized light that passes through the second polarization separation layer 51L and further passes through the second retardation plate 60L is converted into S-polarized light and then applied to the second light modulation device 200L as shown in FIG. On the other hand, the S-polarized light that is incident and reflected by the second polarization separation layer 51L enters the second light modulation device 200L while maintaining its polarization state. As described above, the light mainly composed of the S-polarized light component with respect to the polarization combining film 301 is emitted from the second illumination device 100L.

  The first light modulation device 200R is a light modulation device that modulates light from the first illumination device 100R according to image information to form a full-color image. As shown in FIG. 1, the first light modulation device 200R is arranged immediately after the first polarization conversion element 50R. With such a configuration, it is possible to reduce the loss of light amount and the disturbance of the polarization direction, and as a result, it is possible to further increase the light utilization efficiency.

  Note that the second light modulation device 200L is the same as the first light modulation device 200R, and a description thereof will be omitted.

  Each of the first light modulation device 200R and the second light modulation device 200L includes a color filter CF1, which is not shown in FIG. The color filter CF1 is a Bayer array color filter, as shown in FIG. In FIG. 5, a reflective dichroic filter that transmits red light and reflects other color light is disposed in the area indicated by R, and green light is allowed to pass through the area indicated by G. A reflective dichroic filter that reflects the colored light is disposed, and a reflective dichroic filter that transmits the blue light and reflects the other colored light is disposed in the region indicated by B. In the color filter CF1, one pixel includes one region R that transmits red light, one region B that transmits blue light, and two regions G that transmit green light. In other words, each of the plurality of pixels included in the first light modulation device 200R includes one red sub-pixel that modulates red light, one blue sub-pixel that modulates blue light, and two green that modulates green light. It consists of sub-pixels.

  Instead of the color filter CF1 shown in FIG. 5, the color filter CF2 shown in FIG. 6 may be used. The color filter CF2 is different from the color filter CF1 in that none of the dichroic filters described above is provided in one of the two regions G included in the color filter CF1. In FIG. 6, the region is indicated by W. That is, the light incident on the region W indicated by W of the color filter CF2 is transmitted as white light through the color filter CF2. When the first light modulation device 200R includes the color filter CF2, each pixel has one red sub-pixel that modulates red light, one blue sub-pixel that modulates blue light, and one green that modulates green light. It consists of a sub-pixel and one white sub-pixel that modulates white light. For this reason, the amount of transmitted light can be increased as a whole, and color temperature deterioration caused by excessive green color can be prevented.

  The light modulation device is a transmissive liquid crystal light modulation device in which a liquid crystal as an electro-optical material is hermetically sealed between a pair of transparent glass substrates. Each of the plurality of pixels included in the liquid crystal light modulation device includes, for example, a polysilicon TFT as a switching element, and modulates the polarization state of light incident from the incident-side polarizing plate in accordance with a given image signal.

  The first light modulation device 200R includes a first incident-side polarizing plate 70R disposed on the first polarization conversion element 50R side and a first emission-side polarizing plate 80R disposed on the projection optical system 400 side. Also have. The first incident-side polarizing plate 70R, the first light modulation device 200R, and the first emission-side polarizing plate 80R modulate light emitted from the first illumination device 100R. The second light modulation device 200L includes a second incident-side polarizing plate 70L disposed on the second polarization conversion element 50L side and a second emission-side polarizing plate 80L disposed on the projection optical system 400 side. And further. The second incident-side polarizing plate 70L, the second light modulation device 200L, and the second emission-side polarizing plate 80L modulate the light emitted from the second illumination device 100L.

  The first image light emitted from the first emission side polarizing plate 80R and the second image light emitted from the second emission side polarizing plate 80L are incident on the polarization beam combining means 300. The polarization composite film 301 reflects light incident as S-polarized light on the polarization composite film 301 and transmits light incident as P-polarized light on the polarization composite film 301. Therefore, the first exit-side polarizing plate 80R is provided so that the first image light mainly includes the P-polarized component with respect to the polarization composite film 301. In addition, the second exit-side polarizing plate 80L is provided so that the second image light mainly includes the S-polarized component with respect to the polarization composite film 301. For this reason, as shown in FIG. 1, the full color first image light emitted from the first liquid crystal light modulator and the full color second image light emitted from the second liquid crystal light modulator are Are combined by the polarization combining film 301 and enter the projection optical system 400. The illumination optical axis of the combined image light is indicated by 100ax. In this way, an image is formed on the screen SCR.

  FIG. 7 is a diagram showing the relative light intensity (relative luminous flux intensity) of the light emitted from the projector 1000 according to the present embodiment. According to the projector 1000, as shown in FIG. 7, it is possible to project a bright projected image with a substantially uniform light intensity distribution over the entire projection area on the screen SCR.

  Further, since the projector 1000 includes the first light modulation device 200R and the second light modulation device 200L, for example, an image for the right eye is displayed on the first light modulation device 200R, and the second light modulation device. By displaying the left-eye image on 200L, a bright 3D display is possible.

  Here, the light emission characteristics of the white light emitting diode will be described. FIG. 9 is a diagram showing the light emission characteristics of white light emitting diodes that are generally commercially available. FIG. 9A is a diagram illustrating a current value with respect to an applied voltage, and FIG. 9B is a diagram illustrating a relative light output value (a rated output value is 1.0) with respect to the current value.

  For example, the current value at 67% of the rated output is 800 mA, and the voltage value at that time is 3.2V. Therefore, the input power at that time is about 2.6 W. The current value at 134% of the rated output is 2200 mA, and the voltage value at that time is 3.6V. Therefore, the input power at that time is about 7.9 W. In other words, when two white light emitting diodes with 67% of the rated output are used to obtain 134% of the rated output, the input power is about 5.2W, which is twice that of 2.6W. When one light emitting diode is used, about 7.9 W is required. Obviously, the power utilization efficiency is higher when two white light emitting diodes are used. In addition, if the total sum of electric power input to the lighting device is the same, a projector like the present invention is configured using two pairs of lighting devices and a liquid crystal light modulator rather than using a pair of lighting devices and a liquid crystal light modulator. By doing so, a brighter projected image can be formed on the screen SCR.

  For this reason, according to the projector 1000 according to the embodiment, since the two illumination devices of the first illumination device 100R and the second illumination device 100L are provided, the power input to one illumination device is more than half of the conventional one. Can be small. Therefore, the power consumption can be reduced as a whole. Moreover, the heat generation of the first light source device 10R and the second light source device 10L can be made smaller than in the past. Since the calorific value is small, it is advantageous from the viewpoint of cooling, and the temperature rise of the first light source device 10R and the second light source device 10L can be made smaller than before.

  In addition, according to the projector 1000 according to the embodiment, the first light source device 10R includes the first solid-state light source 24R that generates excitation light and the first fluorescent layer 26R that generates fluorescence from the excitation light. . The second light source device 10L includes a second solid light source 24L that generates excitation light and a second fluorescent layer 26L that generates fluorescence from the excitation light. For this reason, it is possible to make the projector small and light. In addition, according to the projector 1000 according to the embodiment, high luminance can be obtained as compared with the size.

  Further, according to the projector 1000 according to the embodiment, the passage portion 42R has a rectangular shape centered on the optical axis of the illumination device (first illumination optical axis 100Rax), and the passage portion 42L has the optical axis of the illumination device ( Since it has a rectangular shape centered on the second illumination optical axis 100Lax), it is possible to use the optical elements in the subsequent stage without waste.

  Further, according to the projector 1000 according to the embodiment, the first collimator optical system 30R is composed of two or more collimator lenses, and at least one surface is composed of an aspheric surface. It becomes possible to collimate light with high accuracy. Furthermore, the first collimator optical system 30R can adjust the light flux density distribution in the parallel light using an aspherical surface. Similarly to the first collimator optical system 30R, the second collimator optical system 30L can collimate the light from the first fluorescent layer 26R with high accuracy, and further uses an aspherical surface. It is also possible to adjust the light flux density distribution in the parallel light.

  Further, according to the projector 1000 according to the embodiment, the first collimator optical system 30R and the second collimator optical system 30L emit light having a substantially uniform light flux density distribution. Even if it is not used, a sufficiently uniform in-plane light intensity distribution can be obtained, and the projector can be further reduced in size and weight.

  Further, according to the projector 1000 according to the embodiment, each of the first light modulation device 200R and the second light modulation device 200L is a transmissive liquid crystal light modulation device, and therefore, what is a case of a reflection type light modulation device? In contrast, it is possible to combine two types of polarized light, and as a result, it is possible to reduce the power input to the illumination device. In addition, a projector capable of bright 3D display can be realized.

  Further, according to the projector 1000 according to the embodiment, since the color filter has a reflective dichroic filter, it is possible to reflect color light that is not incident on the light modulation device, and to prevent overheating of the light modulation device due to absorption of color light. It becomes possible.

  Further, according to the projector 1000 according to the embodiment, since the color filter has the reflective dichroic filter, it is possible to reflect a part of the excitation light that has reached the color filter, and the excitation light is used as the first fluorescence. By making the light incident again on the layer 26R, the utilization efficiency of the excitation light can be further increased.

  Further, according to the projector 1000 according to the embodiment, since the color filter is a Bayer color filter, it is possible to project a projected image with a high apparent resolution.

  When the color filter CF2 is used as the color filter in the projector 1000 according to the embodiment, the pixel includes one red sub-pixel, one blue sub-pixel, one green sub-pixel, and one white sub-pixel. Therefore, it is possible to project a high-brightness projection image with a good color temperature compared to the case where the pixel is composed of one red sub-pixel, one blue sub-pixel, and two green sub-pixels. It becomes.

  In addition, according to the projector 1000 according to the embodiment, the first light source device 10R includes the first white light emitting diode 20R having the first solid state light source 24R and the first fluorescent layer 26R. The reliability is high and a full color image can be projected.

[Embodiment 2]
FIG. 8 is a plan view showing an optical system of the projector 2000 according to the present embodiment.
In FIG. 8, the difference from the projector 1000 is only the optical path deflecting means 500L arranged in the second illumination device 150L, and thus detailed description thereof is omitted. The optical path deflecting unit 500L is used when the position of the second light source device 10L is changed when there is a restriction in arrangement due to the positional relationship with the cooling device.

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

  (1) In the above embodiment, the cube type (configuration by bonding of prisms) is used for the polarization combining means 300, but a plate type (configuration in which a film having a specific polarization characteristic is deposited on the surface of a glass plate) is used. It is also possible.

  (2) In the above embodiment, the first light source device 10R and the second light source device 10L that emit “light that can be used as white light” are used. However, the present invention is not limited to this. is not. A light source device that emits light other than “light that can be used as white light” (for example, light that includes a large amount of a specific color light component) may be used.

  (3) In the above embodiment, the first solid light source 24R and the second solid light source 24L that generate blue light having an emission intensity peak of about 460 nm are used. However, the present invention is not limited to this. is not. For example, a solid light source that generates blue light having an emission intensity peak of 440 nm to 450 nm may be used as the first solid light source 24R and the second solid light source 24L. With such a configuration, it is possible to improve the fluorescence generation efficiency in the phosphor.

  (4) Although the light emitting diode is used as the solid light source in the above embodiment, the present invention is not limited to this. For example, a semiconductor laser may be used as the solid light source.

  (5) In the above embodiment, the first illumination device 100R emits light mainly composed of the P-polarized light component with respect to the polarization composition film 301, and the second illumination device 100L emits S-polarization with respect to the polarization composition film 301. Although the light mainly composed of the components was emitted, the present invention is not limited to this. The first illumination device 100R emits light mainly composed of the S-polarized component with respect to the polarization composition film 301, and the second illumination device 100L emits light mainly composed of the P-polarization component with respect to the polarization composition film 301. Also good.

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

  10R ... first light source device, 10L ... second light source device, 20R ... first white light emitting diode, 20L ... second white light emitting diode, 24R ... first solid state light source, 24L ... second solid state light source, 26R ... first fluorescent layer, 26L ... second fluorescent layer, 30R ... first collimator optical system, 30L ... second collimator optical system, 50R ... first polarization conversion element, 50L ... second Polarization conversion element, 60R ... first retardation plate, 60L ... second retardation plate, 80R ... first exit side polarization plate, 80L ... second exit side polarization plate, 100R ... first illumination device, 100L, 150L ... second illumination device, 100Rax ... first illumination optical axis, 100Lax ... second illumination optical axis, 100ax ... illumination optical axis of combined image light, 200R ... first light modulation device, 200L ... second light modulator, 300 ... polarized light Forming means, 301 ... polarization combining film, 400 ... projection optical system, 1000 and 2000 ... projector, SCR ... screen.

Claims (10)

A first lighting device;
A first light modulation device that forms first image light by modulating light emitted from the first illumination device according to image information;
A second lighting device;
A second light modulation device that forms second image light by modulating light emitted from the second illumination device according to image information;
Polarization combining means for combining the first image light and the second image light;
A projection optical system that projects the light combined by the polarization combining means,
The first light modulation device includes a plurality of pixels including a sub-pixel that modulates first color light and a sub-pixel that modulates second color light different from the first color light,
The second light modulation device includes a plurality of pixels including a sub-pixel that modulates the first color light and a sub-pixel that modulates the second color light. The projector according to claim 1.
The polarization synthesis means includes a polarization synthesis film,
The first light modulation device and the second light modulation device are transmissive liquid crystal light modulation devices,
The first image light mainly includes a P-polarized component with respect to the polarization composite film,
The projector according to claim 2, wherein the second image light mainly includes an S-polarized component with respect to the polarization composite film. The projector according to claim 2,
The first illumination device emits light mainly composed of either a P-polarized component for the polarization-combining film or an S-polarized component for the polarization-combining film,
The projector, wherein the second illuminating device emits light mainly composed of the other of the P-polarized light component for the polarized light combining film and the S-polarized light component for the polarized light combining film. The projector according to claim 1,
The projector according to claim 1, wherein each of the first light modulation device and the second light modulation device includes a light modulation device having a color filter. The projector according to claim 4,
The projector according to claim 1, wherein the color filter is formed of a reflective dichroic filter. The projector according to claim 4 or 5,
The pixel included in the first light modulation device further includes a sub-pixel that modulates the first color light, a third color light different from the second color light, and a sub-pixel that modulates a fourth color light. ,
The sub-pixel that modulates the first color light, the sub-pixel that modulates the second color light, the sub-pixel that modulates the third color light, and the sub-pixel that modulates the fourth color light are provided in a Bayer arrangement. A projector characterized by being provided. The projector according to claim 6,
The projector according to claim 4, wherein the fourth color light is white light. The projector according to any one of claims 1 to 7,
The first illumination device includes a first solid-state light source and a first fluorescent layer that emits fluorescence when irradiated with excitation light emitted from the first solid-state light source. The projector according to claim 8, wherein
The projector according to claim 1, wherein the first solid-state light source and the first fluorescent layer constitute a white light emitting diode. The projector according to claim 1,
The first display device and the second display device are characterized in that the first display device and the second display device display an image for a right eye on one side and a left eye on the other side.