JP2009265140A - Projection apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a projection apparatus with less color-break, and which can be easily adjusted. <P>SOLUTION: The projection apparatus includes: an illumination light source system 380 that emits illumination light that is different from others in terms of a polarization direction of at least a part of continuous frequency region components; a first polarization conversion element 340 that changes the polarization direction of the illumination light; a spatial light modulator 100 that modulates the illumination light to projection light; a control means 220 that controls the spatial light modulator 100 on the basis of an input signal; a light separating/synthesizing means 400 that separates the illumination light and synthesizes the projection light; a polarization element 360 arranged on the optical path of the projection light and a projection optical system 370 that projects a projection light. The light separating/synthesizing means 400 includes a plurality of dichroic films having different properties in the same plane. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a technology of a projection device, and more particularly to a technology of a projection device having a spatial light modulator.

  Spatial light modulators used in projectors are roughly classified into liquid crystal devices that modulate the polarization direction of incident light by sealing liquid crystal between transparent substrates and applying a potential difference, and micro MEMS (Micro Electro Mechanical Systems) mirrors. A micromirror device is used that deflects the light by electrostatic force and controls the reflection direction of illumination light.

  US Pat. No. 5,214,420 discloses a configuration of the spatial light modulator 15 using the micromirror device shown in FIG. 12A. The spatial light modulation device 15 reflects a light beam 9 emitted from the light source 10 by a mirror element 17 corresponding to each pixel arranged on the surface of the spatial light modulation device 15, thereby forming a desired image on the screen 2. indicate. Each mirror element 17 is arranged on the array as shown in FIG. 12B, and the state of each mirror element 17 is the ON state in which the light beam 9 is reflected in the direction of the screen 2 by the computer 19 and the state of the screen 2. It is controlled to one of the OFF states that do not reflect in the direction.

  The control of each mirror element 17 by the computer 19 is performed, for example, via a circuit having a memory structure as shown in FIG. 12C disclosed in US Pat. No. 5,285,407, and the stable state of the memory is changed to the ON state of the mirror element 17. And correspond to the OFF state.

  The gradation of the projected image is expressed by controlling the ON state (or OFF state) period of the mirror element 17, and the ON state (or OFF state) period is generally composed of multi-bits from the computer 19. Controlled by binary data. FIG. 12D shows an example in which the ON period is controlled by binary data consisting of 4 bits for simplicity. Weights of 1, 2, 4, and 8 are assigned to each bit of binary data consisting of 4 bits from the lower bits, and the ON period is determined by the sum of the weights of the bits where 1 is set. As a result, 16 types of periods from 0 to 15 can be specified. That is, 16 types of gradation can be expressed. In this method, it is known that the gradation that can be expressed is limited by the bit size of binary data, more specifically, the relative weight assigned to the least significant bit (LSB) determined according to the bit size of binary data. It has been.

  By the way, projection apparatuses using a spatial light modulator are classified into a single-plate projection apparatus that performs display using a single spatial light modulator and a multi-plate projection apparatus that performs display using a plurality of spatial light modulators. can do.

  FIG. 13 shows a space allocated to each color by separating white light emitted from the light source 50 into red (R), green (G), and blue (B) rays by the color separating means 60 arranged in the optical path. A three-plate projection device that irradiates the light modulator 71, the spatial light modulator 72, and the spatial light modulator 73, recombines the light beams modulated by the spatial light modulators by the optical path combining unit 80, and then projects the light by the projection lens 90. Is a kind of a multi-plate projection device.

  The color separation means 60 uses, for example, a dichroic film that separates by utilizing the difference in the frequency of each RGB color light, or controls the polarization state of each RGB color light in advance, and the difference in the polarization state of each color light. Some use a polarization beam splitter that separates the light by using a polarization beam splitter. US Pat. No. 5,865,520 discloses a configuration using a dichroic membrane.

  The three-plate type projector illustrated in FIG. 13 does not suffer from problems such as a decrease in light use efficiency and a color break as seen in a single-plate type projector described later, but a member obtained by using a plurality of spatial light modulators. There are problems such as increased costs, increased man-hours for adjustment, and relatively complicated optical systems. Projectors using expensive micromirror devices with a low unit cost are limited to some business applications and high-end users only. The actual situation is adopted.

  On the other hand, in the single-plate projector illustrated in FIG. 14, a period (one frame) for displaying one image is divided into subframes, and any one of R, G, and B illumination light within each subframe period. Are applied to the spatial light modulator 70, and the spatial light modulator 70 sequentially displays images corresponding to the respective colors in synchronization with the irradiated illumination light.

A single-plate projector has fewer components than the multi-plate projector, and has the advantages of fewer member costs and adjustment man-hours. On the other hand, if the subframe period is not set sufficiently short, color breaks will occur. There is a problem of doing.
US Pat. No. 5,214,420 US Pat. No. 5,285,407 US Pat. No. 5,865,520

  In view of the circumstances as described above, an object of the present invention is to provide a projection device that generates less color breaks than a single-plate projection device and is easy to adjust as compared to a three-plate projection device.

  According to a first aspect of the present invention, there is provided an illumination light source system that emits illumination light whose polarization direction of at least some continuous frequency domain components is different from the others, and a first polarization conversion element that switches the polarization direction of the illumination light. A spatial light modulator that modulates the illumination light into projection light, a control means that controls the spatial light modulator based on an input signal, and a light beam separation and synthesis means that separates the illumination light and synthesizes the projection light. And a polarizing element disposed on the optical path of the projection light, and a projection optical system that projects the projection light, wherein the light beam separating / combining means includes a plurality of dichroic films having different characteristics in the same plane. A projection apparatus is provided.

  According to a second aspect of the present invention, in the projection device according to the first aspect, the illumination light and the projection light have independent spatial regions of light beams on a light beam separation / combination surface of the light beam separation / combination means. In addition, a first dichroic film is disposed in a spatial region of the light beam on the light beam separation / combination surface of the illumination light, and a first dichroic film is disposed in the spatial region of the light beam on the light beam separation / combination surface of the projection light. A projection apparatus is provided in which a second dichroic film having different characteristics from the film is disposed.

  According to a third aspect of the present invention, in the projection apparatus according to the first aspect, the spatial light modulator is a deflection type spatial light modulator, and is incident on a light beam separation / combination surface of the light beam separation / combination means. Provided is a projection device whose corners are equal between the illumination light and the projection light.

  According to a fourth aspect of the present invention, in the projection apparatus according to the first aspect, the light beam separating / combining means includes two optical members, and the plurality of dichroic films having different characteristics are the two optical members. A projection device disposed on the joint surface of the projector is provided.

According to a fifth aspect of the present invention, there is provided the projection apparatus according to the fourth aspect, wherein both of the two optical members are prisms having the same shape.
According to a sixth aspect of the present invention, in the projection device according to the first aspect, the light beam separating / combining means includes a single plate glass surface, and the plurality of dichroic films having the different characteristics are arranged on the single plate glass surface. A projection apparatus is provided.

According to a seventh aspect of the present invention, there is provided the projection apparatus according to the second aspect, wherein the first dichroic film and the second dichroic film have opposite characteristics.
According to an eighth aspect of the present invention, in the projection apparatus according to the first aspect, the spatial light modulator is a first spatial light modulator that modulates the first light beam separated by the light beam separation / combination means. And a second spatial light modulator that modulates the second light beam separated by the light beam separating / combining means.

  According to a ninth aspect of the present invention, in the projection apparatus according to the eighth aspect, the first dichroic film includes a first polarization direction different from that of the other illumination light emitted from the illumination light source system. Separating light in a frequency domain and light in a second frequency domain different from the first frequency domain toward the first spatial light modulator, the first frequency domain and the second frequency domain And a projection device that separates light in a third frequency region different from that toward the second spatial light modulator.

  According to a tenth aspect of the present invention, in the projection device according to the ninth aspect, the first spatial light modulator inputs the light in the first frequency domain and the light in the second frequency domain. The second spatial light modulator modulates the light in the third frequency domain, and the first spatial light modulator modulates the light in the first frequency domain. A projection apparatus that modulates during one of the periods during which the light in the second frequency region is modulated is provided.

An eleventh aspect of the present invention provides the projection apparatus according to the first aspect, wherein the illumination light source system includes a wavelength-selective polarizing element.
A twelfth aspect of the present invention provides the projection apparatus according to the first aspect, wherein the illumination light source system includes a laser light source.

  According to a thirteenth aspect of the present invention, in the projection device according to the ninth aspect, the first dichroic film and the second spatial light modulator, or the second spatial light modulator and the second spatial light modulator. Provided is a projection device in which a second polarization conversion element that switches a polarization direction in synchronization with the first polarization conversion element is disposed between the dichroic film.

  According to a fourteenth aspect of the present invention, in the projection device according to the thirteenth aspect, the first spatial light modulator inputs the light in the first frequency domain and the light in the second frequency domain. The second spatial light modulator modulates the light in the third frequency domain, and the first spatial light modulator modulates the light in the first frequency domain. And a projection apparatus for modulating the light in the second frequency region during the period during which the light is modulated.

A fifteenth aspect of the present invention provides the projection apparatus according to the thirteenth aspect, wherein the third frequency region is a green region.
A sixteenth aspect of the present invention provides the projection apparatus according to the thirteenth aspect, wherein the third frequency region is a red region.

A seventeenth aspect of the present invention provides the projection apparatus according to the thirteenth aspect, wherein the third frequency region is a blue region.
According to an eighteenth aspect of the present invention, there is provided the projection apparatus according to the first aspect, wherein the spatial light modulator is a micromirror array device including a plurality of mirror elements having variable deflection angles.

  According to the present invention, it is possible to provide a projection apparatus that generates less color breaks than a single-plate projection apparatus and that is easier to adjust than a three-plate projection apparatus.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[Embodiment 1]
FIG. 1 is a conceptual diagram showing a configuration example of a projection apparatus according to an embodiment of the present invention, and FIGS. 2A, 2B, and 2C are ray separation / synthesis in a light source separation configuration unit 400 included in the projection apparatus. It is a conceptual diagram which illustrates this.

Hereinafter, the configuration of the projection apparatus according to this embodiment and the optical path until a light beam is projected onto the screen 500 will be described with reference to FIGS. 1 and 2A, 2B, and 2C.
As illustrated in FIG. 1, the projection apparatus according to the present embodiment includes an illumination light source system 380, a polarization conversion element 340, a light source separation component 400, a polarization element 360, a projection optical system 370, a screen 500, and a spatial light modulator 100a. , A two-plate projector including a spatial light modulator 100b, a spatial light modulator control unit 220, and a polarization element control unit 250.

The illumination light source system 380 includes a polarized light source system 310, an illumination optical system 320, and a wavelength selective polarization element 330, and each plays the following roles.
The polarized light source system 310 includes a non-polarized and white light source 300, a reflector 301, and a polarizing element 302 that transmits only a light beam having a certain polarization direction, and plays a role of aligning the illumination light 601 in a certain polarization direction. Here, the polarization optical system 310 may further include an element called a PS integrator (not shown) so as not to waste light from the light source 300 as much as possible. This element once splits the incident light with PBS (polarization beam splitter), then emits one polarized light as it is, and rotates the polarized light by 90 degrees by placing a half-wavelength plate on the optical path of the other polarized light. , And can be emitted in the same optical path as the above-mentioned transmitted polarized light. If this element is used, almost all light rays from the light source 300 can be used.

The illumination optical system 320 includes a condenser lens 321, a rod-type condenser 322, and a condenser lens 323, and plays a role of directing the illumination light 601.
The wavelength-selective polarizing element 330 plays a role of rotating the polarization direction in a direction different from the other only in some continuous frequency domain components when transmitting the illumination light 601 polarized in a certain direction by the polarized light source system 310. .

  Since each of these plays the above role, the illumination light source system 380 converts the polarization of the illumination light 601 in which the polarization direction of a part of the continuous frequency domain (hereinafter referred to as the first frequency domain) component is different from the others. The light is incident on the light source separation component 400 via the element 340.

  The polarization conversion element 340 can convert the polarization direction of all components of the incident illumination light 601. Note that this conversion function can be enabled or disabled depending on the state of the polarization conversion element 340. Hereinafter, the state in which the conversion function is enabled is referred to as an ON state, and the state in which the conversion function is disabled is referred to as an OFF state.

For this reason, the illumination light 601 incident on the light source separation component 400 does not depend on the state of the polarization conversion element 340, and always has a different polarization direction only in the first frequency domain component.
The light source separation component 400 includes triangular prisms 410 and 420 having the same shape bonded with the long side surfaces as the bonding surfaces 401, and two dichroic films 402 and dichroic films 403 disposed on the bonding surfaces 401.

The dichroic film 402 and the dichroic film 403 are disposed on the bonding surface 401 so as not to overlap each other. FIG. 2A shows the arrangement shape and position.
The illumination light 601 incident on the light source separation component 400 is once separated into two, and then synthesized again to be output as projection light 604.

First, separation of the illumination light 601 by the light source separation component 400 will be described.
Of the illumination light 601 incident on the light source separation component 400, a part of a component in a continuous frequency region (hereinafter referred to as a second frequency region) is reflected by the dichroic film 402 disposed on the bonding surface 401 and incident. The light 602a enters the spatial light modulator 100a at a predetermined angle.

  The second frequency region and the first frequency region are frequency regions that do not overlap each other. Hereinafter, the frequency region excluding the first and second frequency regions is referred to as a third frequency region.

The remaining frequency regions, that is, the components in the first and third frequency regions, pass through the dichroic film 402 and enter the spatial light modulator 100b as incident light 602b at a predetermined angle.
That is, the exit surface of the rod-shaped light collector 322, the spatial light modulator 100a, and the spatial light modulator 100b are arranged in an optical conjugate relationship via the light source separation component 400, respectively.

Next, the synthesis of the separated illumination light by the light source separation component 400 will be described.
Incident light 602a having a second frequency region component reflected by the dichroic film 402 is deflected by the mirror 103 of each pixel unit 101 arranged in an array constituting the spatial light modulator 100a, and reflected light 603a is obtained. The light enters the light source separation component 400 again.

  Similarly, the incident light 602b having the first and third frequency domain components transmitted through the dichroic film 402 is deflected by the mirror 103 of each pixel unit 101 arranged in an array constituting the spatial light modulator 100b. The reflected light 603b enters the light source separation component 400 again.

  The dichroic film 403 has characteristics opposite to those of the dichroic film 402, and transmits the second frequency region component reflected by the dichroic film 402, while passing through the dichroic film 402. Reflects frequency domain components.

  Therefore, the reflected light 603a deflected by the spatial light modulator 100a passes through the dichroic film 403, whereas the reflected light 603b deflected by the spatial light modulator 100b is reflected by the dichroic film 403.

As a result, the reflected light 603 a and the reflected light 603 b are combined on the joint surface 401 of the light source separation component 400 and are incident on the polarizing element 360 as the projection light 604.
The polarizing element 360 has a characteristic of transmitting only a component having a certain polarization state in the incident projection light 604.

  For this reason, the polarizing element 360 transmits either the first frequency domain component polarized by the wavelength selective polarizing element 330 or the other components (second and third frequency domain components).

The projection light 604 having a certain polarization state transmitted through the polarization element 360 is magnified by the projection optical system 370 and projected onto the screen 500.
Note that whether the polarizing element 360 transmits the first frequency domain component or the other second and third frequency domain components can be controlled by the state of the polarization conversion element 340. .

  In addition, the spatial light modulator 100a and the spatial light modulator 100b are controlled by the spatial light modulator control unit 220, and, as will be described later, incident light 602 (which is deflected while the mirror 103 of the pixel unit 101 is turned on) ( Only a part of the incident light 602a (incident light 602b) and the incident light 602 (incident light 602a, incident light 602b) deflected during the vibration state is effectively used as the reflected light 603 (reflected light 603a, reflected light 603b). The light enters the light source separation component 400.

FIG. 2A is a three-dimensional view showing how the light source separation component 400 described above separates and combines light rays.
The illumination light 601 is separated at the joint surface 401 into incident light 602a and incident light 602b, and the reflected light 603a and the reflected light 603b reflected by the spatial light modulator 100a and the spatial light modulator 100b, respectively, at the joint surface 401. A state of being synthesized and output as projection light 604 is shown.

  FIG. 2B is a front view when the light source separation component 400 is viewed from the A direction shown in FIG. 2A, and shows the relationship between the incident angles of the illumination light 601 and the reflected light 603 to the bonding surface 401. . Here, an example is shown in which the illumination light 601 from the illumination light source system 380 and the reflected light 603 reflected in the normal direction by the spatial light modulator 100 match the incident angles on the joint surface of the light source separation component 400. ing.

This is a configuration considering the incident angle characteristics of the dichroic film 402 and the dichroic film 403 disposed on the bonding surface 401.
Note that the incident angles of the illumination light 601 and the reflected light 603 on the joint surface 401 are not necessarily matched. When the incident angle is deviated due to optical design, it is possible to use a dichroic film 402 used for the illumination light 601 and a dichroic film 403 used for the reflected light 603 having different incident angle characteristics. May be.

  FIG. 2C is a side view of the light source separation component 400 when viewed from the B direction shown in FIG. 2A, and the light beam separation / combination performed by the light source separation component 400 determines the depth direction of the light source separation component 400. It shows that it is done using.

  As illustrated in FIG. 2C, since the illumination light 601 and the reflected light 603 pass through different optical paths, the dichroic film 402 may be disposed in a region on the bonding surface 401 including the optical path of the illumination light 601. What is necessary is just to arrange | position in the area | region on the joint surface 401 containing the optical path of the reflected light 603. FIG.

Therefore, the dichroic film 402 and the dichroic film 403 can be arranged so as not to overlap each other.
As described above, in the present embodiment, the separation and synthesis of light rays are performed using two dichroic films (dichroic film 402 and dichroic film 403). In addition, as a beam separation / combination means, for example, there is a method using a polarization beam splitter prism. The dichroic film used in the present embodiment has a feature that the change in the separation characteristics depending on the incident angle of the light beam is gradual as compared with the polarizing beam splitter prism. For this reason, in this embodiment, there is an advantage that the degree of freedom in designing the incident angle is relatively large and the design is easy to perform.

  In the present embodiment, a plurality of dichroic films (dichroic film 402, dichroic film 403) are arranged on the joint surface 401 of two prisms (prism 410, prism 420) having the same shape constituting the light source separation component 400. It has a simple configuration. As a result, the plurality of dichroic films are arranged on the same plane. As a result, the adjustment of the arrangement position between the plurality of dichroic films is also limited to the same plane, and is illustrated in FIG. Compared to a configuration in which a plurality of dichroic films are arranged on different planes, there is an advantage that adjustment can be performed relatively easily.

  Alternatively, the dichroic film 402 may be disposed and manufactured on the prism 410, the dichroic film 403 may be disposed and manufactured on the prism 420, and the prism 410 and the prism 420 may be bonded together.

  FIG. 3 is a conceptual diagram showing a modified example of the configuration of the projection apparatus according to the embodiment of the present invention, and is a diagram focusing on the light source separation configuration unit 400 and the spatial light modulator 100. Compared to the configuration illustrated in FIG. 1, the shape of the light source separation component 400 and the arrangement of the spatial light modulator 100 are different.

  The light source separation component 400 illustrated in FIG. 1 is illustrated in FIG. 3, whereas the long side surfaces of the triangular prisms 410 and 420 having the same shape are bonded to each other as the bonding surface 401. The light source separation component 400 has a configuration in which the surfaces of one of the bases of the prisms 410 and 420 having the same shape are bonded together as a joint surface 401. As a result, the light source separation component 400 has a triangular prism shape as a whole.

  Note that the dichroic film 402 and the dichroic film 403 disposed on the bonding surface 401 have different characteristics as in FIG. More specifically, the dichroic film 402 on which the illumination light 601 is incident reflects the light beam of the second frequency domain component and transmits the light beam of the other components. On the other hand, the dichroic film 403 on which the reflected light 603 is incident transmits the light beam of the second frequency domain component and reflects the light beam of the other components.

  Further, as illustrated in FIG. 3, each of the prisms (prism 410 and prism 420) constituting the light source separation component 400 between the incident on the light source separation component 400 and the projection onto the projection optical system. On the long side, total reflection occurs once each before and after incidence on the spatial light modulator 100 (spatial light modulator 100a, spatial light modulator 100b).

  In the case of this modification, the incident light 602 (incident light 602a and incident light 602b) separated into two by the dichroic film 402 at the bonding surface 401 is output from the same plane of the light source separation component 400, The two spatial light modulators 100 (spatial light modulator 100a and spatial light modulator 100b) that deflect the separated incident light 602 can be arranged on the same plane.

  This facilitates the arrangement in which the spatial light modulator 100a and the spatial light modulator 100b are packaged, and also facilitates positioning work when the spatial light modulator 100 is arranged in the package because it is limited to the same plane. The following effects can be obtained. Further, when the spatial light modulators 100a and 100b are identical devices, for example, a spatial light modulator using a MEMS mirror, it is also possible to configure the spatial light modulators 100a and 100b as a single device that is diced from the same wafer.

FIG. 4 is a conceptual diagram showing still another modification of the configuration of the projection apparatus according to the embodiment of the present invention. The configuration illustrated in FIG. 1 is different from the configuration of the light source separation configuration unit 400.
The light source separation component 400 illustrated in FIG. 4 is disposed on the single glass plate surface that replaces the joint surface 401 of the two prisms in the light source separation component 400 illustrated in FIG. Two dichroic films 402 and dichroic films 403 are included.

  In the case of this modification, compared to the projection apparatus illustrated in FIG. 1, two prisms are not required, so that the member cost can be suppressed and the construction can be made relatively inexpensively. In addition, effects such as miniaturization of the projection apparatus can be obtained within a range that does not block the optical path of the light beam.

  FIGS. 5A and 5B are diagrams illustrating the polarization state on the optical path of the frequency domain component of each color of light red (R), green (G), and blue (B) and the projection onto the screen 500 in the projection apparatus illustrated in FIG. It is a table | surface which illustrates the frequency domain component performed.

  Each row of the table indicates the polarization state immediately after being emitted from the light source 300, immediately after being transmitted through the polarization element 302, immediately after being transmitted through the wavelength selective polarization element 330, and immediately after being transmitted through the polarization conversion element 340, and each spatial light modulation. The frequency domain component incident on the device 100 and the frequency domain component projected on the screen 500 are shown.

5A shows a case where the polarization conversion element 340 is in an OFF state, and FIG. 5B shows a case where the polarization conversion element 340 is in an ON state.
Here, the first, second, and third frequency regions described above correspond to the blue (B), red (R), and green (G) frequency regions, respectively.

Hereinafter, changes in the polarization states of the RGB color components of the light rays in the projection apparatus according to the present embodiment will be described in detail with reference to FIGS. 5A and 5B.
First, the case where the polarization conversion element 340 illustrated in FIG. 5A is in an OFF state will be described.

Illumination light 601 is emitted from the light source 300. The RGB components of the illumination light 601 immediately after being output from the light source 300 are all in a non-polarized state (N) (see ROW1-1).
Thereafter, the illumination light 601 enters the polarizing element 302 included in the polarized light source system 310. Of the illumination light 601 incident on the polarizing element 302, only the component in the P polarization state (P) is transmitted through the polarizing element 302 (see ROW2-1).

  Here, an example is shown in which the polarizing element 302 transmits only the P-polarized component, but it is not necessarily required to be P-polarized light. Since only light having a polarization state in a certain direction needs to be transmitted, a polarizing element 302 that transmits an S-polarized component may be used.

  The illumination light 601 that has passed through the polarizing element 302 enters the wavelength selective polarizing element 330 via the illumination optical system 320. Of the illumination light 601 incident on the wavelength-selective polarizing element 330, only the blue (B) component (first frequency domain component) changes to the S-polarized state (S), and the other red (R) component (second) Frequency domain component) and green (G) component (third frequency domain component) are transmitted in the P polarization state (P) (see ROW3-1).

  Thus, the illumination light 601 emitted from the illumination light source system 380 is in a state in which only a part of continuous frequency domain components (here, the blue (B) component which is the first frequency domain component) is different. Yes.

  The illumination light 601 that passes through the wavelength selective polarization element 330 and is emitted from the illumination light source system 380 enters the polarization conversion element 340. The polarization conversion element 340 is controlled to be in the OFF state by the polarization element control unit 250 and transmits the incident illumination light 601 without changing the polarization state. That is, the blue (B) component is transmitted in the S-polarized state, and the red (R) and green (G) components are transmitted in the P-polarized state (see ROW4-1).

  The illumination light 601 transmitted through the polarization conversion element 340 enters the light source separation component 400, is separated into two by the dichroic film 402, and enters the spatial light modulator 100a or the spatial light modulator 100b. Due to the separation of the light beam by the dichroic film 402, only the red (R) component (second frequency domain component) is incident on the spatial light modulator 100a (SLM1), and the remaining blue (B) and green (G) components are spatial light. The light enters the modulator 100b (SLM2) (see ROW5-1).

  The reflected light 603a reflected by the spatial light modulator 100a and the reflected light 603b reflected by the spatial light modulator 100b are combined by the dichroic film 403 and become projection light 604. The projection light 604 is projected onto the screen 500 via the polarizing element 360 and the projection optical system 370. At this time, the polarizing element 360 transmits only the red (R) and green (G) components in the P-polarized state (P) out of the projection light 604 incident on the polarizing element 360 and projects it onto the screen 500 ( See ROW6-1).

That is, among the three RGB color components, one color reflected by the spatial light modulator 100 a and one color reflected by the spatial light modulator 100 b are simultaneously projected onto the screen 500.
Here, an example is shown in which the polarizing element 360 transmits only the P-polarized component, but it is not necessarily required to be P-polarized light. Since only light having a polarization state in a certain direction needs to be transmitted, a polarizing element 360 that transmits the S-polarized component may be used.

  Moreover, although both the polarizing element 302 and the polarizing element 360 showed the example which permeate | transmits only a P polarization component, the polarization direction which the polarizing element 302 and the polarizing element 360 permeate | transmit does not necessarily need to correspond. The polarizing element 302 and the polarizing element 360 may be elements that transmit different polarization states.

Next, the case where the polarization conversion element 340 illustrated in FIG. 5B is in the ON state will be described.
Until the light is emitted from the illumination light source system 380, the process is the same as that in FIG. 5A. The P-polarized illumination light 601 emitted from the polarization light source system 310 is blue by the wavelength selective polarization element 330 via the illumination optical system 320. Only the component (B) (first frequency domain component) changes to the S polarization state (see ROW1-2 to ROW3-2).

  The illumination light 601 that has passed through the wavelength selective polarization element 330 is incident on the polarization conversion element 340. The polarization conversion element 340 is controlled to be in an ON state by the polarization element control unit 250, and transmits the incident illumination light 601 with its polarization state reversed. That is, the blue (B) component is in the P-polarized state, and the red (R) and green (G) components are in the S-polarized state (see ROW4-2).

  The illumination light 601 transmitted through the polarization conversion element 340 enters the light source separation component 400, is separated into two by the dichroic film 402, and enters the spatial light modulator 100a or the spatial light modulator 100b. Due to the separation of light rays by the dichroic film 402, only the red (R) component (second frequency domain component) is incident on the spatial light modulator 100a (SLM1) and the remaining blue (B) and green are separated, as in FIG. 4A. The component (G) is incident on the spatial light modulator 100b (SLM2) (see ROW5-2).

  The reflected light 603a reflected by the spatial light modulator 100a and the reflected light 603b reflected by the spatial light modulator 100b are combined by the dichroic film 403 to become projection light 604. The projection light 604 is projected onto the screen 500 via the polarizing element 360 and the projection optical system 370. At this time, the polarizing element 360 transmits only the blue (B) component in the P-polarized state (P) out of the projection light 604 incident on the polarizing element 360 and projects it onto the screen 500 (see ROW6-2). ).

  That is, only one color reflected by the spatial light modulator 100b among the RGB three-color components is projected onto the screen 500. Here, one color projected via the spatial light modulator 100b is different from one color projected via the spatial light modulator 100b in FIG. 5A.

  As described above, the components of the projection light 604 projected onto the screen 500 are different depending on whether the polarization conversion element 340 is in the ON state or in the OFF state, and all the components are projected in one of the two states. There is a relationship. Therefore, by controlling the polarization element control unit 250 to periodically switch the state of the polarization conversion element 340, it is possible to project all the RGB components and express a color image.

  In the present embodiment, as described above, a color image is reproduced by mixing three colors of RGB using two kinds of color light emission states corresponding to the ON state and the OFF state of the polarization conversion element 340. . For this reason, compared to a single-plate projector that reproduces a color image using three or more color emission states corresponding to each of RGB using a color wheel or the like, there is a state necessary for reproducing a color image by color mixing. Less is enough. This is because when the limit of the switching processing speed due to the responsiveness of the circuit elements used in the projection apparatus is taken into consideration, the period required for color image reproduction can be shortened, and as a result, the single-plate projection Compared to the apparatus, the occurrence of color breaks can be suppressed.

FIG. 6 is a conceptual diagram showing still another modification of the configuration of the projection apparatus according to the embodiment of the present invention. The configuration illustrated in FIG. 1 is different from the configuration of the illumination light source system 380.
In the illumination light source system 380 illustrated in FIG. 6, a laser light source 303 is used instead of the non-polarized and white light source 300 in the polarized light source system 310 illustrated in FIG. Since the laser light source 303 has directivity and can emit light having the same polarization direction, the reflector 301 and the polarizing element 302 are omitted.

  Further, the laser light source 303 is composed of, for example, a plurality of sub-light sources each emitting a predetermined frequency domain component, and only a specific frequency domain component can be emitted while shifting the polarization direction. The wavelength selective polarizing element 330 is also omitted.

In addition, when the laser light source 303 is configured to be physically rotatable, the polarization conversion element 340 can be omitted.
In the case of the present modification, independent control can be performed for each frequency domain component by using the laser light source 303 and independently controlling the sub-light sources. According to this, the light quantity of the illumination light 601 can be controlled for each color, and in addition to the control of the spatial light modulator 100, it is possible to obtain an effect such that a finer gradation expression can be realized. In addition, since the configuration of the illumination light source system 380 becomes simpler, the labor required for adjustment is reduced.

FIG. 7 is a conceptual diagram illustrating a configuration example of each pixel unit 101 arranged on the array in the spatial light modulator 100 configuring the projection apparatus according to an embodiment of the present invention.
As illustrated in FIG. 7, the pixel unit 101 includes a mirror 103 that is supported on an unillustrated substrate 104 via an elastic hinge 107 so as to be tiltable.

On the substrate 104, an OFF electrode 108a and an ON electrode 108b are disposed at symmetrical positions with the elastic hinge 107 interposed therebetween.
When a predetermined potential is applied to the OFF electrode 108a, the mirror 103 is attracted by the Coulomb force and tilted to a position where it contacts the OFF electrode 108a that also serves as a stopper. Thereby, the incident light incident on the mirror 103 is reflected on the optical path at the OFF position deviated from the optical axis of the projection optical system 370. The state of the mirror 103 at this time is referred to as an OFF state.

  When a predetermined potential is applied to the ON electrode 108b, the mirror 103 is attracted by the Coulomb force and tilted to a position where it comes into contact with the ON electrode 108b that also serves as a stopper. Thereby, the incident light incident on the mirror 103 is reflected on the optical path at the ON position that coincides with the optical axis of the projection optical system 370. The state of the mirror 103 at this time is referred to as an ON state.

  Further, when the mirror 103 is in a position where it abuts against the OFF electrode 108a or the ON electrode 108b, the application of the potential to the OFF electrode 108a (or the ON electrode 108b) is stopped, whereby the mirror 103 and the OFF electrode 108a (or the ON electrode) are stopped. 108 b) disappears, and the mirror 103 performs free vibration according to the characteristics of the elastic hinge 107. As a result, the incident light incident on the mirror 103 along with the free vibration of the mirror 103 is in the ON position where the optical path of the OFF position deviating from the optical axis of the projection optical system 370 coincides with the optical axis of the projection optical system 370. It is reflected in the optical path between the optical paths. The state of the mirror 103 at this time is called a vibration state.

  An OFF capacitor 105a is connected to the OFF electrode 108a, and this OFF capacitor 105a is connected to the bit line 110-1 via an OFF gate transistor 102a made of an FET (field effect transistor) or the like.

  An ON capacitor 105b is connected to the ON electrode 108b, and the ON capacitor 105b is connected to the bit line 110-2 via an ON gate transistor 102b made of an FET (field effect transistor) or the like.

Opening and closing of the OFF gate transistor 102 a and the ON gate transistor 102 b is controlled by the word line 120.
That is, a horizontal row of pixel units 101 connected to an arbitrary word line 120 are selected at the same time, and charge / discharge of charges to the OFF capacitor 105a and the ON capacitor 105b is controlled by the bit line 110-1 and the bit line 110-2. As a result, ON / OFF / vibration of the mirror 103 in each pixel unit 101 in the horizontal row is individually controlled.

The OFF capacitor 105a and the OFF gate transistor 102a on the OFF electrode 108a side constitute a so-called DRAM structure memory cell M1.
Similarly, the ON capacitor 105b and the OFF gate transistor 102b on the ON electrode 108b side also constitute a memory cell M2 having a DRAM structure.

The basic control of the mirror 103 included in the spatial light modulator 100 in this embodiment will be described.
In the following description, Va (1, 0) indicates that a predetermined voltage Va is applied to the OFF electrode 108a and not applied to the ON electrode 108b.

Va (0, 1) indicates that the voltage Va is not applied to the OFF electrode 108a and the voltage Va is applied to the ON electrode 108b.
Va (0, 0) indicates that the voltage Va is not applied to either the OFF electrode 108a or the ON electrode 108b.

Va (1, 1) indicates that the voltage Va is applied to both the OFF electrode 108a and the ON electrode 108b.
8A, FIG. 8B, FIG. 8C, FIG. 8D, FIG. 8E, and FIG. 8F show the configuration of the pixel unit 101 including the mirror 103, the elastic hinge 107, the OFF electrode 108a, and the ON electrode 108b, and the mirror 103 in the ON / OFF state. The basic example of the state control controlled to a vibration state is shown.

  FIG. 8A shows that when a predetermined voltage Va is applied only to the ON electrode 108b (Va (0, 1)), the mirror 103 is attracted to the ON electrode 108b from the neutral state and tilts to become the ON state. Represents. In the ON state of the mirror 103, the reflected light passing through the mirror 103 is captured by the projection optical system 370 and projected as projection light. FIG. 8B shows the amount of reflected light reflected by the ON state.

  Further, in FIG. 8C, when a predetermined voltage Va is applied only to the OFF electrode 108a (Va (1, 0)), the mirror 103 is attracted to the OFF electrode 108a from the neutral state and tilted to enter the OFF state. It is shown that. In the OFF state of the mirror 103, the reflected light deviates from the projection optical system 370 and does not become projection light. FIG. 8D shows the amount of reflected light reflected by the OFF state.

  FIG. 8E shows an example in which the mirror 103 performs free vibration with the maximum amplitude between the tilt position where the mirror 103 abuts against the ON electrode 108b (Full ON) and the tilt position where the mirror 103 abuts against the OFF electrode 108a (Full OFF). (Va (0,0)). FIG. 8F shows the amount of reflected light reflected by the vibration state.

  In this way, by utilizing the free vibration state of the mirror 103, the amount of projection light to the projection optical system 370 can be controlled in detail. Thereby, a finer gradation expression can be realized as compared with the case where the mirror 103 is controlled in the ON state and the OFF state.

  In the examples of FIGS. 8A, 8B, 8C, 8D, 8E, and 8F described above, the voltage Va expressed by a binary value of 0 or 1 is applied to each of the two OFF electrodes 108a and ONb 108b. However, by increasing the level of Va to multiple values, the level of Coulomb force generated between the mirror 103, the OFF electrode 108a, and the ON electrode 108b is increased. The tilt angle of the mirror 103 can be controlled.

  Further, in the examples of FIGS. 8A, 8B, 8C, 8D, 8E, and 8F described above, the mirror 103 (hinge electrode 109) is described as being at the ground potential, but this mirror 103 is described. By applying an offset voltage to the mirror 103, it is possible to control the tilt angle of the mirror 103 more finely.

  FIG. 9 is a block diagram illustrating a configuration example of a control unit provided in a projection apparatus having the above-described two-plate spatial light modulator 100. The control unit includes a spatial light modulator 100 (spatial light modulator 100a and spatial light modulator 100b), a video signal input unit 200, a frame memory 210, a spatial light modulator control unit 220, a video signal analysis unit 230, and a sequencer 240. , A polarizing element control unit 250, a light source control unit 260, a light source driving unit 270, and a light source 300 (laser light source 303).

The sequencer 240 is composed of a microprocessor or the like, and controls the overall operation timing of the control unit and the spatial light modulator 100.
The frame memory 210 holds input digital video data 701 coming from an external device (not shown) connected to the video signal input unit 200, for example, for one frame. The input digital video data 701 is updated every moment when one frame is displayed.

  The spatial light modulator control unit 220 processes the input digital video data 701 read from the frame memory 210 and separates the input digital video data 701 into subfields corresponding to a plurality of frequency domain components, and the spatial light modulator 100 (spatial light modulator 100). 100a and spatial light modulator 100b) are output to spatial light modulator 100 (spatial light modulator 100a and spatial light modulator 100b) as data for realizing ON / OFF control and vibration control of mirror 103.

  The sequencer 240 outputs a polarization element control signal to the polarization element control unit 250 in synchronization with the generation of data for controlling the mirror 103 in the spatial light modulator control unit 220. As a result, the polarization element control unit 250 is controlled so that the light of the frequency domain component corresponding to the generated data is projected onto the screen 500.

  The video signal analysis unit 230 outputs a video analysis signal 702 for generating various light source pulse patterns based on the input digital video data 701 input from the video signal input unit 200.

  The light source control unit 260 uses the light source profile control signal to generate a light source pulse pattern based on the video analysis signal 702 obtained from the video signal analysis unit 230 via the sequencer 240, and then the light source 300 (laser) via the light source driving unit 270. The light emission operation of the illumination light 601 in the light source 303) is controlled.

  As described above, according to the present embodiment, a color image can be reproduced by mixing three colors of RGB using two types of color light emission states corresponding to the ON state and the OFF state of the polarization conversion element 340. Compared with the plate-type projection device, the period required for color image reproduction can be shortened, and as a result, the occurrence of color breaks can be suppressed.

Further, by arranging a plurality of dichroic films used as color separation / synthesis means on the same plane, the arrangement of the dichroic films can be adjusted relatively easily.
Furthermore, the use of a dichroic film, which is not a polarizing beam splitter prism but a gentle change in separation characteristics depending on the incident angle of light rays, is used as a color separation / combination means. There is an advantage.

Thereby, it is possible to provide a projection device that suppresses the occurrence of color breaks and is relatively easy to adjust.
[Embodiment 2]
Hereinafter, only the main differences from the above-described first embodiment will be described, and the present embodiment will be described.

  FIG. 10 is a conceptual diagram showing a configuration example of a projection apparatus according to another embodiment of the present invention. The projection apparatus illustrated in FIG. 10 has a configuration in which a polarization conversion element 350 is added to the optical path between the dichroic film 402 and the spatial light modulator 100a in addition to the configuration of the projection apparatus illustrated in FIG. It has become.

  The polarization conversion element 350 may be disposed on the optical path of the second frequency component from the separation of the light beam by the dichroic film 402 to the synthesis of the light beam by the dichroic film 403. Therefore, it may be disposed between the spatial light modulator 100a and the dichroic film 403.

In addition, the polarization conversion element 350 has an ON state and an OFF state, like the polarization conversion element 340, and can switch between enabling and disabling the polarization conversion process for the transmitted light.
The polarization element control unit 250 controls the polarization conversion element 340 and the polarization conversion element 350 in synchronization, whereby the polarization conversion element 350 converts the polarization of the second frequency component light beam deflected by the spatial light modulator 100a. It functions to cancel the polarization due to the element 340. Thereby, the light beam of the second frequency component deflected by the spatial light modulator 100a does not depend on the state of the polarization conversion element 340 and always has a constant polarization direction. Further, since the polarizing element 360 has a characteristic of transmitting the fixed polarization direction of the light beam having the second frequency component, the light beam having the second frequency component is always projected onto the screen 500.

  As described above, in the present embodiment, by adding the polarization conversion element 350, the light amount of the second frequency component light that is periodically blocked by the polarization element 360 in the projection apparatus exemplified in the first embodiment is reduced. It is possible to effectively use and provide a brighter image.

  11A and 11B are tables exemplifying polarization states on the optical path of the frequency domain components of each color of red (R), green (G), and blue (B) of the light beam in the projection apparatus illustrated in FIG. is there. FIG. 11A shows a case where both the polarization conversion element 340 and the polarization conversion element 350 are in an OFF state, and FIG. 11B shows a case where both the polarization conversion element 340 and the polarization conversion element 350 are in an ON state.

Here, the first, second, and third frequency regions described above correspond to the blue (B), red (R), and green (G) frequency regions, respectively.
Hereinafter, the change in the polarization state of each RGB color component of the light beam in the projection apparatus illustrated in FIG. 10 will be described in detail with reference to FIGS. 11A and 11B.

First, the case where both the polarization conversion element 340 and the polarization conversion element 350 illustrated in FIG. 11A are in the OFF state will be described.
The process until the light is emitted from the illumination light source system 380 is the same as that in the first embodiment, and the P-polarized illumination light 601 emitted from the polarization light source system 310 is passed through the illumination optical system 320 and the wavelength selective polarization element 330. Thus, only the blue (B) component (first frequency domain component) changes to the S polarization state (see ROW1-3 to ROW3-3).

  The illumination light 601 that has passed through the wavelength selective polarization element 330 is incident on the polarization conversion element 340. Since the polarization conversion element 340 is controlled to be in the OFF state by the polarization element control unit 250, the polarization conversion element 340 transmits the incident illumination light 601 without changing the polarization state. That is, the blue (B) component is S-polarized light, and the red (R) and green (G) components are P-polarized states (see ROW4-3).

The illumination light 601 that has passed through the polarization conversion element 340 enters the single plate glass surface and is separated into two by the dichroic film 402 disposed on the surface.
The red (R) component (second frequency domain component) reflected by the dichroic film 402 is incident on the polarization conversion element 350. The polarization conversion element 350 is controlled by the polarization element control unit 250 to be in the same OFF state as the polarization conversion element 340, and transmits the incident illumination light 601 without changing the polarization state. That is, the red (R) component is in the P polarization state (see ROW5-3).

  Thereafter, the red (R) component illumination light 601 transmitted through the polarization conversion element 350 enters the spatial light modulator 100a, and the remaining blue (B) and green (G) component illumination light 601 transmitted through the dichroic film 402. Enters the spatial light modulator 100b (SLM2) (see ROW6-3).

  The reflected light 603a reflected by the spatial light modulator 100a and the reflected light 603b reflected by the spatial light modulator 100b are combined by the dichroic film 403 to become projection light 604. The projection light 604 is projected onto the screen 500 via the polarizing element 360 and the projection optical system 370. At this time, the polarizing element 360 transmits only the red (R) and green (G) components in the P-polarized state (P) out of the projection light 604 incident on the polarizing element 360 and projects it onto the screen 500 ( See ROW7-3).

That is, among the three RGB color components, one color reflected by the spatial light modulator 100 a and one color reflected by the spatial light modulator 100 b are simultaneously projected onto the screen 500.
Next, the case where both the polarization conversion element 340 and the polarization conversion element 350 illustrated in FIG. 11B are in the ON state will be described.

  Until the light is emitted from the illumination light source system 380, the process is the same as in FIG. 11A. The P-polarized illumination light 601 emitted from the polarization light source system 310 is transmitted through the illumination optical system 320 by the wavelength selective polarization element 330. Only the blue (B) component (first frequency domain component) changes to the S polarization state (see ROW1-4 to ROW3-4).

  The illumination light 601 that has passed through the wavelength selective polarization element 330 is incident on the polarization conversion element 340. Since the polarization conversion element 340 is controlled to be in the ON state by the polarization element control unit 250, the polarization state of the incident illumination light 601 is inverted and transmitted. That is, the blue (B) component is P-polarized, and the red (R) and green (G) components are S-polarized (see ROW4-4).

The illumination light 601 that has passed through the polarization conversion element 340 enters the single plate glass surface and is separated into two by the dichroic film 402 disposed on the surface.
The red (R) component (second frequency domain component) reflected by the dichroic film 402 is incident on the polarization conversion element 350. The polarization conversion element 350 is controlled to be in the same ON state as the polarization conversion element 340 by the polarization element control unit 250 and inverts the polarization state of the incident illumination light 601 and transmits it. That is, the red (R) component is in the P-polarized state (see ROW5-4).

  The red (R) component illumination light 601 transmitted through the polarization conversion element 350 enters the spatial light modulator 100a, and the remaining blue (B) and green (G) component illumination light 601 transmitted through the dichroic film 402 is in space. The light enters the optical modulator 100b (SLM2) (see ROW 6-4).

  The reflected light 603a reflected by the spatial light modulator 100a and the reflected light 603b reflected by the spatial light modulator 100b are combined by the dichroic film 403 to become projection light 604. The projection light 604 is projected onto the screen 500 via the polarizing element 360 and the projection optical system 370. At this time, the polarizing element 360 transmits only the red (R) and blue (B) components in the P-polarized state (P) of the projection light 604 incident on the polarizing element 360 and projects it onto the screen 500 ( See ROW7-4).

  That is, as in the case of FIG. 11A, among the RGB three-color components, one color reflected by the spatial light modulator 100a and one color reflected by the spatial light modulator 100b are simultaneously projected onto the screen 500. Is done. Here, one color projected via the spatial light modulator 100b is different from one color projected via the spatial light modulator 100b in FIG. 11A.

  As described above, the light of the second frequency domain component deflected by the spatial light modulator 100a is obtained by periodically and synchronously switching the states of the polarization conversion element 340 and the polarization conversion element 350 by the polarization element control unit 250. Always projects the light on the first frequency domain component and the light beam on the third frequency domain component onto the screen 500 in order while projecting it on the screen 500, thereby projecting all the RGB components and expressing a color image. .

This makes it possible to effectively use the light amount of the light beam having the second frequency component and provide a brighter image without wasting it.
In addition, although the 2nd frequency area | region always projected on the screen 500 was illustrated here as red (R), it is not restricted to this.

  For example, in consideration of the characteristics of the human eye sensitive to the frequency domain component of green (G), the second frequency domain always projected on the screen 500 is red (R) or blue (B). Also good.

  In consideration of the characteristic of the laser light source that red (R) light is strong and easy, the second frequency region that is always projected onto the screen 500 may be green (G) or blue (B).

  As described above, according to the present embodiment, it is possible to provide a projection device that reproduces a brighter color image with good color balance.

  Needless to say, the present invention is not limited to the configuration exemplified in the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

It is a conceptual diagram which shows the structural example of the projection apparatus which concerns on one Embodiment of this invention. It is a conceptual diagram which illustrates the isolation | separation synthesis | combination of the light ray in the light source isolation | separation structure part contained in the projection apparatus which concerns on one Embodiment of this invention. It is a conceptual diagram which illustrates the isolation | separation synthesis | combination of the light ray in the light source isolation | separation structure part contained in the projection apparatus which concerns on one Embodiment of this invention. It is a conceptual diagram which illustrates the isolation | separation synthesis | combination of the light ray in the light source isolation | separation structure part contained in the projection apparatus which concerns on one Embodiment of this invention. It is a conceptual diagram which shows the modification of the structure of the projection apparatus which concerns on one Embodiment of this invention. It is a conceptual diagram which shows the further another modification of the structure of the projection apparatus which concerns on one Embodiment of this invention. It is a table | surface which illustrates the polarization state on the optical path of each color light of RGB in case the polarization conversion element of the projector which concerns on one Embodiment of this invention is an OFF state. It is a table | surface which illustrates the polarization state on the optical path of each color light of RGB in the polarization | polarized-light conversion element of the projector which concerns on one Embodiment of this invention in an ON state. It is a conceptual diagram which shows the further another modification of the structure of the projection apparatus which concerns on one Embodiment of this invention. It is a conceptual diagram which shows the structural example of each pixel part arrange | positioned on the array in the spatial light modulator which comprises the projector which concerns on one Embodiment of this invention. It is sectional drawing which shows the ON state of the mirror of the pixel part which comprises the projector which concerns on one Embodiment of this invention. It is a diagram which shows the light quantity projected on a projection optical system in the state of the mirror illustrated by FIG. 8A. It is sectional drawing which shows the OFF state of the mirror of the pixel part which comprises the projector which concerns on one Embodiment of this invention. It is a diagram which shows the light quantity projected on a projection optical system in the state of the mirror illustrated by FIG. 8C. It is sectional drawing which shows the vibration state of the mirror of the pixel part which comprises the projector which concerns on one Embodiment of this invention. It is a diagram which shows the light quantity projected on a projection optical system in the state of the mirror illustrated by FIG. 8E. It is a block diagram which shows the structural example of the projection apparatus which concerns on one Embodiment of this invention. It is a conceptual diagram which shows the structural example of the projection apparatus which concerns on the modification of one Embodiment of this invention. It is a table | surface which illustrates the polarization state on the optical path of each color light of RGB in the polarization | polarized-light conversion element of the projector which concerns on the modification of one Embodiment of this invention in an OFF state. It is a table | surface which illustrates the polarization state on the optical path of each color light of RGB in the polarization conversion element of the projector which concerns on the modification of one Embodiment of this invention in the ON state. It is a conceptual diagram which shows the structure of the projection apparatus of a prior art. It is a conceptual diagram which shows the structure of the mirror element of the projection apparatus of a prior art. It is a conceptual diagram which shows the structure of the drive circuit of the mirror element of the projection apparatus of a prior art. It is a conceptual diagram which shows the format of the image data in the projection apparatus of a prior art. It is a conceptual diagram which shows the structure of the single plate type projector of a prior art. It is a conceptual diagram which shows the structure of the multi-plate type projection apparatus of a prior art.

Explanation of symbols

100 spatial light modulator 100
101 Pixel unit 101
103 mirror 103
220 Spatial light modulator controller 220
250 Polarizing element controller 250
260 Light source controller 260
270 Light source driver 270
300 Light source 300
302 Polarizing element 302
303 Laser light source 303
310 Polarized light source system 310
320 Illumination optical system 320
330 Wavelength selective polarizing element 330
340 Polarization conversion element 340
350 Polarization conversion element 350
360 Polarizing element 360
370 Projection optical system 370
380 Illumination light source system 380
400 Light source separation component 400
401 Bonding surface 401
402 Dichroic film 402
403 Dichroic membrane 403
410 prism 410
420 prism 420
100a Spatial light modulator 100a
100b Spatial light modulator 100b
500 screen 500
601 Illumination light 601
602 Incident light 602
602a Incident light 602a
602b Incident light 602b
603 Reflected light 603
603a Reflected light 603a
603b Reflected light 603b
604 Projection light 604

Claims (18)

An illumination light source system that emits illumination light in which the polarization direction of at least some continuous frequency domain components is different from others;
A first polarization conversion element that switches a polarization direction of the illumination light;
A spatial light modulator that modulates the illumination light into projection light;
Control means for controlling the spatial light modulator based on an input signal;
A light beam separating and combining means for separating the illumination light and combining the projection light;
A polarizing element disposed on the optical path of the projection light;
A projection optical system for projecting the projection light,
The light beam separating / combining means includes a plurality of dichroic films having different characteristics in the same plane. The projection device according to claim 1,
The illumination light and the projection light are independent in the spatial region of each light beam on the light beam separating and combining surface of the light beam separating and combining means,
A first dichroic film is disposed in the spatial region of the light beam on the light beam separating and combining surface of the illumination light,
A projection apparatus, wherein a second dichroic film having characteristics different from those of the first dichroic film is disposed in a spatial region of a light beam on the light beam separating / combining surface of the projection light. The projection device according to claim 1,
The spatial light modulator is a deflection-type spatial light modulator,
The projection apparatus according to claim 1, wherein the illumination light and the projection light have the same incident angle to the light beam separation and synthesis surface. The projection device according to claim 1,
The light beam separating / combining means includes two optical members,
The projection apparatus according to claim 1, wherein the plurality of dichroic films having different characteristics are disposed on a joint surface between the two optical members. The projection apparatus according to claim 4, wherein
Both of the two optical members are prisms having the same shape. The projection device according to claim 1,
The light beam separating / combining means includes a single plate glass surface,
A projection apparatus, wherein the plurality of dichroic films having different characteristics are arranged on the single plate glass surface. The projection apparatus according to claim 2, wherein
The projection apparatus according to claim 1, wherein characteristics of the first dichroic film and the second dichroic film are contradictory. The projection device according to claim 1,
The spatial light modulator modulates a first spatial light modulator that modulates the first light beam separated by the light beam separating / combining means, and a second light beam that modulates the second light beam separated by the light beam separating / combining means. A projection apparatus comprising a spatial light modulator. The projection apparatus according to claim 8, wherein
The first dichroic film includes a light in a first frequency region having a polarization direction different from that of the illumination light emitted from the illumination light source system, and a second frequency region different from the first frequency region. Of light toward the first spatial light modulator,
A projection apparatus that separates light in a third frequency region different from the first frequency region and the second frequency region toward the second spatial light modulator. The projection apparatus according to claim 9, wherein
The first spatial light modulator alternately modulates the light in the first frequency domain and the light in the second frequency domain over time based on an input signal,
The second spatial light modulator is configured to modulate the light in the third frequency domain, the period during which the first spatial light modulator modulates the light in the first frequency domain, or the second spatial light modulator. A projection apparatus that performs modulation during any one of the periods during which light in the frequency domain is modulated. The projection device according to claim 1,
The projection apparatus, wherein the illumination light source system includes a wavelength selective polarizing element. The projection device according to claim 1,
An illumination light source system includes a laser light source. The projection apparatus according to claim 9, wherein
Polarization direction in synchronization with the first polarization conversion element between the first dichroic film and the second spatial light modulator, or between the second spatial light modulator and the second dichroic film A projection apparatus, wherein a second polarization conversion element for switching between the two is disposed. The projection apparatus according to claim 13.
The first spatial light modulator alternately modulates the light in the first frequency domain and the light in the second frequency domain over time based on an input signal,
The second spatial light modulator is configured to modulate light in a third frequency region, a period during which the first spatial light modulator modulates light in the first frequency region, and the second frequency. A projection apparatus that modulates light in a region during modulation. The projection apparatus according to claim 13.
The projection apparatus, wherein the third frequency region is a green region. The projection apparatus according to claim 13.
The projection apparatus, wherein the third frequency region is a red region. The projection apparatus according to claim 13.
The projection apparatus, wherein the third frequency region is a blue region. The projection device according to claim 1,
The projection apparatus, wherein the spatial light modulator is a micro mirror array device including a plurality of mirror elements having variable deflection angles.