LIGHT SOURCE DEVICE AND PROJECTION-TYPE DISPLAY APPARATUS

A light source device according to an embodiment of the present disclosure includes: a first light source section that emits light in a first wavelength region; a wavelength conversion section that is disposed on an optical path of the light in the first wavelength region, and is excited by the light in the first wavelength region emitted from the first light source section to emit light in a second wavelength region different from the first wavelength region; a polarization separation element that is disposed between the first light source section and the wavelength conversion section, and separates incident light on the basis of polarization; and a color separation element that is disposed between the first light source section and the polarization separation element, and separates incident light on the basis of a wavelength region.

TECHNICAL FIELD

The present disclosure relates to, for example, a light source device to be used for illumination of a projection-type display apparatus, and a projection-type display apparatus including the light source device.

BACKGROUND ART

In recent years, in a projector (projection-type display apparatus), a light source device (illumination device) is used which irradiates a phosphor with light from a solid-state light source such as a laser and outputs light resulting from fluorescent emission as illumination light. In addition, the phosphor is formed on a reflective material such as a metal to have a so-called reflective configuration, thereby making it possible to obtain a high output.

For example, PTL 1 discloses a compact light source device with high color purity and wide color gamut which is obtained by condensing and synthesizing fluorescence light and beams of light from a blue solid-state light source and a red solid-state light source in the same optical system.

CITATION LIST

Patent Literature

SUMMARY OF THE INVENTION

Incidentally, a light source device including a wavelength conversion element using a phosphor as a light source is required to improve light extraction efficiency.

It is therefore desirable to provide a light source device and a projection-type display apparatus that make it possible to improve efficiency in extraction of light with uniform polarization.

A light source device according to an embodiment of the present disclosure includes: a first light source section that emits light in a first wavelength region; a wavelength conversion section that is disposed on an optical path of the light in the first wavelength region, and is excited by the light in the first wavelength region emitted from the first light source section to emit light in a second wavelength region different from the first wavelength region; a polarization separation element that is disposed between the first light source section and the wavelength conversion section, and separates incident light on the basis of polarization; and a color separation element that is disposed between the first light source section and the polarization separation element, and separates incident light on the basis of a wavelength region.

A projection-type display apparatus according to an embodiment of the present disclosure includes a light source device, a light modulation element that modulates light emitted from the light source device, and a projection optical system that projects light from the light modulation element. The light source device mounted in the projection-type display apparatus has the same components as those of the light source device of an embodiment of the above-described present disclosure.

According to the light source device of an embodiment of the present disclosure and the projection-type display apparatus of an embodiment of the present disclosure, a polarization separation element that separates incident light on the basis of polarization is disposed between the first light source section and the wavelength conversion section, and a color separation element that separates incident light on the basis of a wavelength region is disposed between this polarization separation element and the first light source section. This makes it possible to improve utilization efficiency of fluorescence (light in the second wavelength region) emitted from the wavelength conversion section.

MODES FOR CARRYING OUT THE INVENTION

Hereinafter, description is given in detail of embodiments of the present disclosure with reference to the drawings. The following description is merely a specific example of the present disclosure, and the present disclosure should not be limited to the following aspects. Moreover, the present disclosure is not limited to arrangements, dimensions, dimensional ratios, and the like of each component illustrated in the drawings. It is to be noted that the description is given in the following order.

1. First embodiment (Example of a light source device in which a polarization separation element is disposed between an excitation light light source section and a wavelength conversion section and a color separation element is disposed between the polarization separation element and the excitation light light source section)

1-1. Configuration of Light Source Device

1-2. Operating Principle of Light Source Device

1-3. Workings and Effects

2. Modification Examples

2-1. Modification Example 1 (Example in which an excitation light light source section and an assist light source section are disposed to be inclined)

2-2. Modification Example 2 (Example in which an excitation light light source section and a wavelength conversion section are disposed to be opposed to each other)

3. Second Embodiment (Example in which a polarization conversion element is further disposed between a polarization separation element and a wavelength conversion section)
4. Third Embodiment (Example in which prism-type PBS is used as a polarization separation element)

5. Modification Examples

5-1. Modification Example 3 (Example in which a color separation element and prism-type PBS are integrated)

5-2. Modification Example 4 (Example in which second and third embodiments are combined)

5-3. Modification Example 5 (Example in which a second embodiment and Modification Example 4 are combined)

5-4. Modification Example 6 (Example in which an angle adjustment mechanism is combined with a polarization separation element and a color separation element)

5-5. Modification Example 7 (Example in which a transmissive wavelength conversion section is used)

6. Application Examples

1. FIRST EMBODIMENT

FIG.1illustrates a configuration example of a light source device (a light source device1) according to a first embodiment of the present disclosure. The light source device1is used, for example, for illumination of a projection-type display apparatus (a projection-type display apparatus6; seeFIG.14) described later.

1-1. Configuration of Light Source Device

The light source device1includes, for example, a light source section11, a wavelength conversion section12, a polarization separation element13, and a color separation element14. In the present embodiment, the polarization separation element13is disposed between the light source section11and the wavelength conversion section12, and the color separation element14is disposed between the light source section11and the polarization separation element13. The light source device1further includes a light source section15and a light-condensing optical system16. The light source section15is disposed to be opposed to the light source section11, for example, with the polarization separation element13and the color separation element14interposed therebetween, and the light-condensing optical system16is disposed between the wavelength conversion section12and the polarization separation element13.

The light source section11includes one or multiple light sources111and lenses112disposed to be opposed to the respective light sources111. The light source111is a solid-state light source that emits light in a predetermined wavelength region, and is provided to excite phosphor particles included in a phosphor layer122of the wavelength conversion section12described later. It may be possible to use, as the light source111, a semiconductor laser (Laser Diode: LD), for example. Aside therefrom, a light-emitting diode (Light Emitting Diode: LED) may be used.

The light source section11emits, as the excitation light EL, light (blue light) in a wavelength band corresponding to a blue color having a wavelength of 400 nm to 470 nm, for example, or light (ultraviolet: UV light) in an ultraviolet region having a wavelength of 350 nm to 400 nm, for example. In a case of using an ultraviolet laser emitting UV light as the light source111, it is possible to improve luminous efficiency and conversion efficiency as compared with a case of using a blue laser. This makes it possible to improve the percentage of power of fluorescence FL finally available to electric power to be supplied to the light source section11. This light source section11corresponds to a specific example of a “first light source section” of the present disclosure, and blue light or UV light corresponds to a specific example of “light in a first wavelength region” of the present disclosure. It is to be noted that, as used herein, the light in a predetermined wavelength region refers to light having a luminous intensity peak in that wavelength region.

The wavelength conversion section12converts light (excitation light EL) emitted from the light source section11into light (fluorescence FL) in a different wavelength region and emits the light; the wavelength conversion section12corresponds to a specific example of a “wavelength conversion section” of the present disclosure. The wavelength conversion section12is of a so-called reflective type, for example, in which the phosphor layer122is provided on a support substrate121having light reflectivity, and is configured to reflect and emit the fluorescence FL generated by incidence of the excitation light EL.

The support substrate121is provided to support the phosphor layer122, and has a disk shape, for example. The support substrate121preferably has functions not only as a reflective member but also as a heat dissipation member. Therefore, the support substrate121is preferably formed by a metal material having high thermal conductivity. In addition, it is preferable to use a metal material or a ceramic material enabling specular working. This suppresses temperature rise in the phosphor layer122, thus making it possible to improve efficiency in extraction of light (fluorescence FL) in the wavelength conversion section12.

Examples of such a metal material include a simple metal such as aluminum (Al), copper (Cu), molybdenum (Mo), tungsten (W), cobalt (Co), chromium (Cr), platinum (Pt), tantalum (Ta), lithium (Li), zirconium (Zr), ruthenium (Ru), rhodium (Rh), or palladium (Pd), or an alloy including one or more of these metals. Examples of the ceramic material include silicon carbide (SiC), aluminum nitride (AlN), beryllium oxide (BeO), a composite material of Si and SiC, or a composite material of SiC and Al (provided that SiC content is 50% or more).

The phosphor layer122includes multiple phosphor particles, and is excited by the excitation light EL to emit light (fluorescence FL) in a wavelength region different from a wavelength region of the excitation light EL. The phosphor layer122is formed in a plate-like shape, for example, and is configured by a so-called ceramic phosphor or a binder phosphor, for example. The phosphor layer122includes, for example, phosphor particles that each emit light (fluorescence FL) in a wavelength region corresponding to a yellow color by being excited by, for example, blue light (excitation light EL) emitted from the light source section11. This yellow light corresponds to a specific example of “light in a second wavelength region” of the present disclosure. Examples of such phosphor particles include a YAG (Yttrium-Aluminum-Garnet)-based material. The phosphor layer122may further include semiconductor nanoparticles such as quantum dots, organic pigments, or the like.

It is to be noted that the wavelength conversion section12may be mounted with an unillustrated cooling mechanism.

In addition, it may be possible to use, as the wavelength conversion section12, a so-called phosphor wheel12A that is rotatable about a rotational axis (e.g., an axis J123) as illustrated inFIGS.2A and2B. In the phosphor wheel12A, a motor123(drive part) is coupled to a center (O) of the support substrate121, and the support substrate121is rotatable about the axis J123, for example, in an arrow direction C by driving force of the motor123. In the phosphor wheel12A, the phosphor layer122is continuously formed, for example, in a rotational circumferential direction of the support substrate121, for example. In the phosphor wheel12A, rotation of the support substrate121causes an irradiation position of the excitation light EL with respect to the phosphor layer122to be temporally changed (moved) at a speed corresponding to the number of rotations. This makes it possible to avoid a decrease in the conversion efficiency and degradation in phosphor particles caused by long-term irradiation of the excitation light EL to the same position of the phosphor layer122.

The polarization separation element13includes, for example, a polarization beam splitter (PBS); the polarization separation element13separates incident light on the basis of a polarized component, and is configured to reflect S-polarized component and transmit a P-polarized component, for example. Specifically, the polarization separation element13is disposed between the light source section11and the wavelength conversion section12. The polarization separation element13reflects the excitation light EL incident from the light source section11to guide the reflected excitation light EL to the wavelength conversion section12, and reflects a portion of the fluorescence FL incident from the wavelength conversion section12to guide the portion thereof to the color separation element14described later and to guide a rest of the fluorescence FL to an illumination optical system (e.g., an illumination optical system300; seeFIG.15) described later. In addition, assist light AL emitted from the light source section15described later is incident on the polarization separation element13. The assist light AL is reflected by the polarization separation element13, and is guided to the illumination optical system300together with the rest of the fluorescence FL transmitted through the polarization separation element13. That is, the polarization separation element13also functions as a color-synthesizing element (optical path synthesizing element).

The polarization separation element13may be configured by a so-called plate-type polarization beam splitter in which an optical functional film reflecting or transmitting incident light for each polarized component is formed, for example, by vapor deposition on one or both of a pair of surfaces opposed to each other of a glass plate, for example. In the present embodiment, for example, the optical functional film (PBS film) is formed on a surface13S1of the pair of surfaces (a surface13S1and a surface13S2) opposed to each other.

The color separation element14includes, for example, a dichroic mirror, and separates incident light on the basis of a wavelength region. The color separation element14is disposed between the light source section11and the polarization separation element13; the color separation element14is configured to transmit the excitation light EL emitted from the light source section11and reflect a portion of the fluorescence FL incident from the wavelength conversion section12and reflected by the polarization separation element13.

The light source section15includes one or multiple light sources151and lenses152disposed to be opposed to the respective light sources151. The light source151is an auxiliary light source to adjust RGB balance in order to display a wider color gamut in the projection-type display apparatus6, and is disposed to be opposed to the light source section11with, for example, the polarization separation element13and the color separation element14interposed therebetween. It may be possible to use, as the light source151, for example, a semiconductor laser (LD) similarly to the light source section11described above. The use of the semiconductor laser enables etendue to be reduced. Alternatively, a light-emitting diode (LED) may be used. In a case of using the light-emitting diode, it is possible to reduce speckle. In addition, the use thereof is superior to the laser in terms of safety as compared with the case of using the semiconductor laser.

The light source section15preferably includes, for example, multiple types of light sources emitting light in wavelength regions different from one another, e.g., a light source151R emitting light (red light R) in a wavelength region corresponding to a red color, a light source151G emitting light (green light G) in a wavelength region corresponding to a green color, and a light source151B emitting light (blue light B) in a wavelength region corresponding to a blue color. This makes it possible to expand the color gamut of light emitted to the illumination optical system300. In addition, the light source section15may use, as a light source emitting the same color light beam, a light source in which luminous wavelengths are shifted from one another. This makes it possible to reduce speckle. The light source section15corresponds to a specific example of a “second light source section” of the present disclosure, and the red light, the green light, and the blue light emitted from the light source section15each correspond to a specific example of “light in a third wavelength region” of the present disclosure.

The light-condensing optical system16is configured by one or multiple lenses, and includes a collimator lens, for example. The light-condensing optical system16is disposed between the wavelength conversion section12and the polarization separation element13; the light-condensing optical system16condenses the excitation light EL on a predetermined spot diameter to cause the excitation light EL to be incident on the phosphor layer122, and converts the fluorescence FL emitted from the wavelength conversion section12into parallel light to guide it to the polarization separation element13.

1-2. Operating Principle of Light Source Device

In the light source device1, the light source section11and the light source section15are disposed to be opposed to each other along one direction (e.g., a Y-axis direction). The surface13S1and the surface13S2opposed to each other of the polarization separation element13are disposed between the light source section11and the light source section15, for example, at an angle of substantially 45° relative to the Y-axis direction. The excitation light EL emitted from the light source section11is incident on the surface13S1, and light beams (e.g., red light R, green light G, and blue light B) emitted from the light source section15are incident on the surface13S2. Further, the color separation element14is disposed between the light source section11and the polarization separation element13. The wavelength conversion section12is disposed to be opposed to the surface13S1of the polarization separation element13along another direction (e.g., an X-axis direction) orthogonal to the one direction, and the light-condensing optical system16is disposed between the wavelength conversion section12and the polarization separation element13.

In the present embodiment, for example, blue light Bs (excitation light EL) including mainly S-polarized light is emitted from the light source section11. The blue light Bs (excitation light EL) emitted from the light source section11is first transmitted through the color separation element14, and is reflected by the surface13S1of the polarization separation element13toward the light-condensing optical system16. The blue light Bs incident on the light-condensing optical system16is condensed on a predetermined spot diameter, and is emitted toward the wavelength conversion section12. The blue light Bs incident on the wavelength conversion section12excites phosphor particles in the phosphor layer122. In the phosphor layer122, the phosphor particles are excited by irradiation of the blue light Bs to emit the fluorescence FL. The fluorescence FL corresponds to yellow light beams Ys and Yp including the S-polarized component and the P-polarized component, and is emitted toward the light-condensing optical system16. The yellow light beams Ys and Yp incident on the light-condensing optical system16are each converted into parallel light to be outputted toward the polarization separation element13. S-polarized yellow light Ys, of the yellow light beams Ys and Yp incident on the polarization separation element13, is reflected toward the color separation element14by the surface13S1of the polarization separation element13, and P-polarized yellow light Yp thereof is transmitted through the polarization separation element13.

Red light Rs, green light Gs, and the blue light Bs, including mainly S-polarized light, are emitted as assist light AL from the light source section15. The red light Rs, the green light Gs, and the blue light Bs are incident on the surface13S2of the polarization separation element13, and is reflected by the surface13S1. The yellow light Yp transmitted through the polarization separation element13is multiplexed with the red light Rs, the green light Gs, and the blue light Bs to be emitted toward the illumination optical system300.

The yellow light Ys reflected by the surface13S1of polarization separation element13and incident on the color separation element14is reflected toward the surface13S1of the polarization separation element13, and is incident again on the wavelength conversion section12through the polarization separation element13and the light-condensing optical system16. Light in an absorption wavelength region of phosphor particles, of the yellow light Ys incident on the wavelength conversion section12, is reused to excite the phosphor particles, whereas light in another wavelength region is scattered by the phosphor layer122, and a portion of the polarized light is converted and emitted toward the light-condensing optical system16. The repetition thereof enables the S-polarized fluorescence FL to be guided toward the illumination optical system300without being discarded.

1-3. Workings and Effects

The light source device1of the present embodiment includes, between the light source section11and the wavelength conversion section12, the polarization separation element13that separates incident light on the basis of a polarized component, and includes, between this polarization separation element13and the light source section11, the color separation element14that separates incident light on the basis of a wavelength region. This enables utilization as illumination in the projection-type display apparatus6, for example, without discarding one of polarized components of the fluorescence FL emitted from the wavelength conversion section12. This is described below.

The light source for a projector has been shifted from existing discharge tube types to laser excitation phosphor light sources. The main reason for this is that the life of the phosphor light source is very long, i.e., about 10 times longer than that of the discharge tube type light source. Currently, the mainstream phosphor light source uses YAG (Yttrium-Aluminum-Garnet)-based phosphor in many cases. In a projector using this YAG-based phosphor as a phosphor light source, a yellow emission color in a green-to-red continuous wavelength band is dispersed into green and red for using.

However, in a wavelength spectrum of YAG, in a case where an emission wavelength is effectively utilized, achieving a white balance around D65 in a color gamut of sRGB is the limit; in a case of displaying a color gamut wider than that, a wavelength region of each primary color needs to be narrowed to enhance the property of primary colors. In that case, light of an unnecessary portion is discarded. Further, in a case where the RGB balance is changed for displaying a white point, a wavelength of green, of light emitted from the phosphor light source using the YAG-based phosphor, is to be discarded. This poses an issue of not being able to obtain sufficient luminance.

In order to solve the issue described above, it is conceivable to multiplex auxiliary light beams (e.g., R, G, B lasers) of the respective primary colors with fluorescence emitted from a phosphor light source. The above-described light source device condenses and synthesizes fluorescence light and light beams from a blue solid-state light source and a red solid-state light source in the same optical system to thereby achieve high utilization efficiency (low etendue); however, one of the polarized components is discarded in the fluorescence light synthesized in a wavelength region of the laser. In addition, the above-described light source device is configured not to be able to synthesize a green color in principle.

In contrast, in the present embodiment, the polarization separation element13that separates incident light on the basis of a polarized component is provided between the light source section11and the wavelength conversion section12, and the color separation element14that performs separation on the basis of a wavelength region of the incident light is provided between the polarization separation element13and the light source section11. Thus, one polarized component (e.g., S-polarized light (yellow light Ys)) of the fluorescence FL emitted from the wavelength conversion section12is reflected toward the color separation element14, and another polarized component (e.g., P-polarized light (yellow light Yp)) thereof is transmitted through the polarization separation element13to be guided to the illumination optical system300. The S-polarized fluorescence FL (yellow light Ys) incident on the color separation element14is reflected toward the polarization separation element13, and is incident on the wavelength conversion section12through the polarization separation element13and the light-condensing optical system16. Light in an absorption wavelength region of phosphor particles, of the fluorescence FL (yellow light Ys) incident on the wavelength conversion section12, is reused to excite the phosphor particles, whereas light in another wavelength region is scattered by the phosphor layer122, and a portion of the polarized light is converted and emitted toward the light-condensing optical system16. This enables utilization as illumination in the projection-type display apparatus6, for example, without discarding one polarized component (e.g., S-polarized component (yellow light Ys)) included in the fluorescence FL emitted from the wavelength conversion section12.

As described above, in the light source device1of the present embodiment, it is possible to extract a portion of the fluorescence FL as illumination light in the projection-type display apparatus6without discarding it. That is, it is therefore possible to improve efficiency in extraction of light with uniform polarization. In addition, it is possible to improve efficiency of multiplexing with laser light beams of red (R), green (G), and blue (B) emitted from the auxiliary light source (light source section15).

Further, in the present embodiment, as described above, it is possible to multiplex a portion of the fluorescence FL without discarding it, and thus to expand light intensity.

Furthermore, in the present embodiment, the auxiliary light source (light source section15) is disposed to be opposed to the surface13S2of the polarization separation element13. This makes it possible to synthesize the fluorescence FL emitted from the wavelength conversion section12and the laser light beams of the red (R), green (G) and blue (B) emitted from the light source section15in the same optical axis. Thus, it is possible to prevent deterioration of etendue. In addition, it is possible to miniaturize the light source device1.

Further, in the light source device1of the present embodiment, it is possible to improve productivity and robustness to a use environment. For example, a dichroic mirror configuring the color separation element14involves variation of several nm in the cutoff wavelength due to production variation or the like. In addition, a wavelength of the semiconductor laser varies depending on the environmental temperature. For this reason, as in the light source device described above, the light source device that uses the dichroic mirror to synthesize fluorescence light and assist light involves issues of variation in a cutoff wavelength of the dichroic mirror and large environmental fluctuation and production variation due to fluctuation in the wavelength of the laser light. In contrast, the configuration of the light source device1of the present embodiment is not affected by the manufacturing variation of the dichroic mirror and the fluctuation in the wavelength of the laser light. This eliminates the need of strict control over the specification accuracy of the components and the operating temperature or the like of the laser, thus making it possible to reduce manufacturing costs.

Next, description is given of second and third embodiments, Modification Examples 1 to 7, and application examples of the present disclosure. Hereinafter, components similar to those of the foregoing first embodiment are denoted by the same reference numerals, and descriptions thereof are omitted as appropriate.

2. MODIFICATION EXAMPLES

FIG.3illustrates a configuration example of a light source device1A according to Modification Example 1 of the present disclosure. In the foregoing first embodiment, the example has been given in which the light source section11, the color separation element14, the polarization separation element13, and the light source section15are disposed in this order along the one direction (e.g., Y-axis direction), and the wavelength conversion section12is disposed in the other direction (e.g., X-axis direction) orthogonal to the one direction, with respect to the polarization separation element13; however, this is not limitative.

For example, as for the optical members configuring the light source device1A, it is sufficient for the light source section11and the wavelength conversion section12to be disposed at the same angle in opposite directions relative to the normal line of the pair of surfaces (surface13S1and surface13S2) opposed to each other of the polarization separation element13, and it is sufficient for the color separation element14to be disposed to be perpendicular to a traveling direction of light (fluorescence FL (yellow light Ys)) being reflected by the surface13S1of the polarization separation element13and traveling in a direction of the light source section11.

FIG.4illustrates a configuration example of a light source device1B according to Modification Example 2 of the present disclosure. In the foregoing first embodiment, the example has been given in which the light source section11and the light source section15are disposed to be opposed to each other, and the wavelength conversion section12and the light-condensing optical system16are disposed in the orthogonal direction (e.g., X-axis direction) relative to the arrangement direction (e.g., Y-axis direction) of the light source section11and the light source section15; however, this is not limitative.

For example, the laser is able to be rotated 90° relative to the optical axis to thereby change the polarization direction. In that case, it may be possible to adopt the configuration illustrated inFIG.4. That is, the light source section11and the wavelength conversion section12are disposed to be opposed to each other, for example, along the X-axis direction. The polarization separation element13is disposed between the light source section11and the wavelength conversion section12to allow the surface13S1and the surface13S2opposed to each other to form an angle of substantially 45° relative to the X-axis direction, for example; the color separation element14is disposed between the light source section11and the polarization separation element13; and the light-condensing optical system16is disposed between the wavelength conversion section12and the polarization separation element13. The light source section15is disposed along, for example, the Y-axis direction orthogonal to the X-axis direction, to be opposed to the surface13S2of the polarization separation element13. This enables the light source device1B of the present modification example to obtain effects similar to those of the foregoing first embodiment.

It is to be noted that the configuration of the present modification example also holds by disposing a ½λ plate between the polarization separation element13and each of the light source section11and the light source section15

3. SECOND EMBODIMENT

FIG.5illustrates a configuration example of a light source device (a light source device2) according to a second embodiment of the present disclosure. Similarly to the above-described light source device1, the light source device2is used for illumination of the projection-type display apparatus (projection-type display apparatus6) described later, for example. The light source device2of the present embodiment differs from that of the foregoing first embodiment in that a polarization conversion element17is provided between the wavelength conversion section12and the polarization separation element13.

The polarization conversion element17disturbs a polarization state of incident light before emission. Specifically, the polarization conversion element17disturbs a polarization state of the S-polarized fluorescence FL (yellow light Ys) reflected by the color separation element14and reflected by the surface13S1of the polarization separation element13toward the wavelength conversion section12to convert a portion thereof into a P-polarized one, thereby efficiently transmitting the fluorescence FL in the polarization separation element13. The polarization conversion element17is disposed, for example, between the polarization separation element13and the light-condensing optical system16.

It may be possible to use, as the polarization conversion element17, for example, a depolarization film or a depolarization element such as a crystal plate. It may be possible to use, as the polarization conversion element17, for example, a ¼λ plate or a phase difference plate that generates a phase difference of ¼k+α, in addition to those mentioned above. For example, in a case where the ¼λ plate is used as the polarization conversion element17, the S-polarized fluorescence FL (yellow light Ys) reflected by the surface13S1of the polarization separation element13is converted into circularly polarized light to be emitted toward the wavelength conversion section12, and is reflected by the wavelength conversion section12and is converted into linearly polarized light when passing through the ¼λ plate again. The P-polarized fluorescence FL (yellow light Yp) thereof is transmitted through the polarization separation element13to be guided to the illumination optical system300.

As described above, in the present embodiment, the polarization conversion element17is provided between the wavelength conversion section12and the polarization separation element13, specifically, between the polarization separation element13and the light-condensing optical system16, thus enabling the polarization separation element13to efficiently transmit the fluorescence FL. This makes it possible to efficiently multiplex the fluorescence FL with assist light AL, and thus to further improve efficiency in extraction of light with uniform polarization.

FIG.6illustrates a configuration example of a light source device (a light source device3) according to a third embodiment of the present disclosure. Similarly to the above-described light source device1, the light source device3is used for illumination of the projection-type display apparatus (projection-type display apparatus6) described later, for example. The light source device3of the present embodiment differs from that of the foregoing first embodiment in that a prism-type polarization beam splitter is used as a polarization separation element23.

It may be possible for the polarization separation element23to be configured by an optical functional film reflecting or transmitting incident light for each polarized component and prisms attached together with the optical functional film interposed therebetween.

In this manner, the light source device3of the present embodiment uses the prism-type polarization beam splitter as the polarization separation element23, thus enabling an incident surface of the polarization separation element23to be easily disposed to be orthogonal to respective optical axes of the excitation light EL and the assist light AL emitted respectively from the light source section11and the light source section15and the fluorescence FL emitted from the wavelength conversion section12, for example.

In addition, in the light source device3of the present embodiment, the prism-type polarization beam splitter is used as the polarization separation element23, thus making it possible to reduce degradation such as warpage of a substrate, for example, as compared with the case of using the plate-type polarization beam splitter.

5. MODIFICATION EXAMPLES

FIG.7illustrates a configuration example of a light source device3A according to Modification Example 3 of the present disclosure. The prism-type polarization separation element23and the color separation element14may be integrated as illustrated inFIG.7. The prism-type polarization separation element23and the color separation element14are able to be integrally formed, for example, by performing vapor deposition of an optical functional film transmitting or reflecting light in a predetermined wavelength region, of incident light, on a surface, of the prism configuring the polarization separation element23, opposed to the light source section11.

In this manner, in the light source device3A of the present modification example, the polarization separation element23and the color separation element14are integrated, thus making it possible to reduce the number of parts. This makes it possible to reduce the manufacturing costs. In addition, it is possible to reduce the manufacturing process.

FIG.8illustrates a configuration example of a light source device3B according to Modification Example 4 of the present disclosure. The light source device3B of the present modification example is a combination of the foregoing second embodiment and the foregoing third embodiment. In this manner, the prism-type polarization separation element23may be provided between the light source section11and the light source section15, and the polarization conversion element17may be provided between the wavelength conversion section12and the polarization separation element23.

This enables further improvement in efficiency in extraction of light with uniform polarization and enables the incident surface of the polarization separation element23to be easily disposed to be orthogonal to respective optical axes of the excitation light EL and the assist light AL emitted respectively from the light source section11and the light source section15and the fluorescence FL emitted from the wavelength conversion section12.

FIG.9illustrates a configuration example of a light source device3C according to Modification Example 5 of the present disclosure. The light source device3C of the present modification example is a combination of the foregoing second embodiment and Modification Example 3. In this manner, the polarization conversion element17may be disposed between the wavelength conversion section12and the polarization separation element23integrated with the color separation element14.

This makes it possible to reduce the manufacturing costs as well as to obtain the effects of the foregoing Modification Example 4. In addition, it is possible to achieve the reduction in the manufacturing process.

FIG.10illustrates a configuration example of a light source device4according to Modification Example 6 of the present disclosure. The light source device4of the present modification example differs from that of the foregoing first embodiment in that the angles of the polarization separation element13and the color separation element14are adjustable. The adjustment of the angles of the polarization separation element13and the color separation element14is able to be made using, for example, angle adjustment mechanisms140and240illustrated inFIGS.11and12. The angle adjustment mechanisms140and240correspond to specific examples of a “first angle adjustment mechanism” and a “second angle adjustment mechanism” of the present disclosure.

The angle adjustment mechanism140includes, for example, two frames141and142each having a rectangular shape, and, for example, four angle adjustment screws143coupling the two frames141and142together. The two frames141and142are coupled to each other, for example, at four corners by the four angle adjustment screws143. One frame (e.g., frame141), of the two frames141and142, is held by an unillustrated holder, and the polarization separation element13or the color separation element14is attached to another frame (e.g., frame142). In the angle adjustment mechanism140, for example, one of the four angle adjustment screws is fixed, and the remaining ones are made slack, thereby enabling the frame142to be movable, for example, in the Y-axis direction, with the fixed angle adjustment screw143as a fulcrum. This makes it possible to adjust the angle of the polarization separation element13or the color separation element14attached to the frame142.

The angle adjustment mechanism240includes, for example, two frames241and242each having a rectangular shape, and respective two rotational shafts243and244. The two frames241and242have mutually different external shapes, and the frame241is disposed, for example, in a nested manner within a frame of the frame242. The polarization separation element13or the color separation element14is attached to the inner frame241. The frame241and the frame242are coupled to each other by the rotational shaft243at middle portions of two sides opposed to each other. The frame242is coupled to an unillustrated holder via the rotational shaft244at middle portions of two sides opposed to each other different from the two sides coupled to each other by the rotational shaft243. The frame241is rotatable, for example, about a Z-axis direction as a rotational axis, and the frame242is rotatable, for example, about the X-axis direction as a rotational axis. This makes it possible to adjust the angle of the polarization separation element13or the color separation element14attached to the frame241.

In this manner, in the light source device4of the present modification example, the angles of the polarization separation element13and the color separation element14are adjustable, thus making it possible, for example, to adjust the light-condensing position, on the phosphor layer122, of the fluorescence FL (yellow light Ys) reflected by the polarization separation element13and being incident again on the wavelength conversion section12.

This makes it possible, for example, to suppress spread of a light-emitting point in a case where the position of the fluorescence FL (yellow light Ys) condensed on the phosphor layer122is superimposed on the light-condensing position of the excitation light EL. Thus, it is possible to suppress an increase in etendue, and, for example, to improve utilization efficiency of light within the optical system (e.g., illumination optical system300) configuring the projection-type display apparatus6.

In addition, it is possible, for example, to suppress temperature rise and luminance saturation in the phosphor layer122and thus to improve conversion efficiency in a case where the position of the fluorescence FL (yellow light Ys) condensed on the phosphor layer122and the light-condensing position of the excitation light EL are shifted from each other.

FIG.13illustrates a configuration example of a light source device5according to Modification Example 7 of the present disclosure. The light source device5of the present modification example differs from that of the foregoing first embodiment in that a transmissive wavelength conversion section22is used for the configuration.

In the light source device5of the present modification example, the light source section11, the wavelength conversion section22, and the polarization separation element13are disposed in this order along one direction (e.g., X-axis direction). In the polarization separation element13, the surface13S1and the surface13S2opposed to each other are disposed at an angle of substantially 45° relative to the X-axis direction, for example. The color separation element14is disposed to be opposed to the surface13S1of the polarization separation element13in another direction (e.g., Y-axis direction) orthogonal to the one direction. The light source section15is disposed to be opposed to the surface13S2of the polarization separation element13along the other direction (e.g., Y-axis direction) orthogonal to the one direction. The light-condensing optical system16is disposed between the wavelength conversion section12and the polarization separation element13.

The wavelength conversion section22converts light (excitation light EL) emitted from the light source section11into light (fluorescence FL) in a different wavelength region and emits the light; the wavelength conversion section22corresponds to a specific example of the “wavelength conversion section” of the present disclosure. In the wavelength conversion section22, for example, the phosphor layer122is provided on the support substrate221having light-transmissivity, and the color separation element18is provided on a surface, of the support substrate221, on side opposite to the surface on which the phosphor layer122is formed, e.g., on a surface opposed to the light source section11. Further, a lens19to condense the excitation light EL on the phosphor layer122is further disposed between the light source section11and the color separation element18, for example.

Similarly to the color separation element14of the foregoing first embodiment, the color separation element18includes, for example, a dichroic mirror, and separates incident light on the basis of a wavelength region. Specifically, the color separation element18is configured to transmit the excitation light EL and to reflect the fluorescence FL.

It is to be noted that, althoughFIG.13illustrates an example in which the color separation element18is integrally formed with the support substrate221, the color separation element18may be disposed separately from the wavelength conversion section22.

In this manner, also in the light source device5of the present modification example using the transmissive wavelength conversion section22, it is possible to obtain effects similar to those of the foregoing first embodiment.

6. APPLICATION EXAMPLES

Application Example 1

FIG.14is a functional block diagram illustrating an overall configuration of the projection-type display apparatus (projection-type display apparatus6) according to Application Example 1. This projection-type display apparatus6is, for example, a display apparatus that projects an image on a screen68(projection surface). The projection-type display apparatus6is coupled to an unillustrated external image supply apparatus, for example, a computer such as a PC or various image players via an I/F (interface), and performs projection onto the screen68on the basis of an image signal inputted to the interface.

The projection-type display apparatus6includes, for example, a light source drive unit61, the light source device1, a light modulation device62, a projection optical system63, an image processing unit64, a frame memory65, a panel drive unit66, a projection optical system drive unit67, and a control unit60.

The light source drive unit61outputs a signal to control an emission timing of the light source (light source111and light source151) disposed in the light source device1. The light source drive unit61includes, for example, a PWM setting section, a PWM signal generation section, a limiter, and the like, which are unillustrated. The light source drive unit61controls a light source driver of the light source device1under the control of the control unit60, and performs PWM control on the light source111and the light source151to thereby turn on or off the light source111and the light source151or adjust the luminance.

Although not particularly illustrated, the light source device1includes, in addition to the components described in the foregoing first embodiment, for example, the light source driver that drives each of the light source111and the light source151, and a current value setting section that sets each of current values when driving the light source111and the light source151. On the basis of power supplied from an unillustrated power source circuit, the light source driver generates a current with a current value set by the current value setting section in synchronization with a signal inputted from the light source drive unit61. The generated current is supplied to each of the light source111and the light source151.

On the basis of an image signal, the light modulation device62modulates light (illumination light) outputted from the light source device1to generate image light. The light modulation device62includes, for example, three transmissive or reflective light valves corresponding to respective colors of RGB described later. Examples thereof include a liquid crystal panel that modulates blue light (B), a liquid crystal panel that modulates red light (R), and a liquid crystal panel that modulates green light (G). It may be possible to use, as the reflective liquid crystal panel, for example, a liquid crystal element such as LCOS (Liquid Crystal On Silicon). However, as the light modulation device62, there may be used not only the liquid crystal element, but also another light modulation element, e.g., DMD (Digital Micromirror Device). Respective color light beams of the RGB modulated by the light modulation device62are synthesized by an unillustrated cross dichroic prism or the like to be guided to the projection optical system63.

The projection optical system63includes a lens group or the like to form an image by projecting light modulated by the light modulation device62onto the screen68.

The image processing unit64acquires an externally inputted image signal, and makes determination of an image size, determination of resolution, determination of whether a still image or a moving image, and the like. In a case of a moving image, attributes of image data such as frame rates are also determined. In addition, in a case where resolution of the acquired image signal differs from display resolution of each liquid crystal panel of the light modulation device62, resolution conversion processing is performed. The image processing unit64develops the image after each processing in the frame memory65for each frame, and outputs, as a display signal, the image for each frame developed in the frame memory65to the panel drive unit66.

The panel drive unit66drives each liquid crystal panel of the light modulation device62. Driving the panel drive unit66changes a transmittance of light in each of pixels arranged on each liquid crystal panel, thus allowing an image to be formed.

The projection optical system drive unit67includes a motor that drives a lens disposed in the projection optical system63. Under the control of the control unit60, the projection optical system drive unit67drives the projection optical system63, for example, and performs zoom adjustment, focus adjustment, aperture adjustment, and the like, for example.

The control unit60controls the light source drive unit61, the image processing unit64, the panel drive unit66, and the projection optical system drive unit67.

In this projection-type display apparatus6, for example, providing the above-described light source device1makes it possible to achieve simplification and miniaturization of the entire apparatus.

Configuration Example 1 of Projection-Type Display Apparatus

FIG.15is a schematic view of an example (a projection-type display apparatus6A) of an overall configuration of an optical system configuring the projection-type display apparatus6. The projection-type display apparatus6A is a projection-type display apparatus of a reflective 3LCD type that performs light modulation using a reflective liquid crystal panel (Liquid Crystal Display: LCD).

As illustrated inFIG.15, the projection-type display apparatus6A includes the light source device1, the illumination optical system300, an image-forming unit400, and a projection optical system500in order.

For example, the illumination optical system300includes, from a position close to the light source device1, fly-eye lenses310(310A and310B), a polarization conversion element320, a lens330, dichroic mirrors340A and340B, reflective mirrors350A and350B, lenses360A and360B, a dichroic mirror370, and polarizing plates380A to380C.

The fly-eye lenses310(310A and310B) homogenize an illuminance distribution of illumination light from the light source device1. The polarization conversion element320functions to align a polarization axis of incident light in a predetermined direction. For example, the polarization conversion element320converts randomly polarized light into P-polarized light. The lens330condenses light from the polarization conversion element320toward the dichroic mirrors340A and340B. The dichroic mirrors340A and340B selectively reflect light in a predetermined wavelength region, and selectively transmit light in a wavelength region other than the predetermined wavelength region. For example, the dichroic mirror340A reflects mainly red light Lr and green light Lg in a direction of the reflective mirror350A. In addition, the dichroic mirror340B reflects mainly blue light Lb in a direction of the reflective mirror350B. The reflective mirror350A reflects light (mainly red light Lr and green light Lg) from the dichroic mirror340A toward the lens360A, and the reflective mirror350B reflects light (mainly blue light Lb) from the dichroic mirror340B toward the lens360B. The lens360A transmits light (mainly red light Lr and green light Lg) from the reflective mirror350A, and condenses the light on the dichroic mirror370. The dichroic mirror370selectively reflects green light Lg toward the polarizing plate380C, and selectively transmits light in a wavelength region other than the green light Lg. The polarizing plates380A to380C include a polarizer having a polarization axis in a predetermined direction. For example, in a case where the polarization conversion element320performs conversion into P-polarized light, the polarizing plates380A to380C transmit P-polarized light, and reflect S-polarized light.

The reflective polarizing plates410A to410C respectively transmit light (e.g., P-polarized light) having the same polarization axis as the polarization axis of polarized light from the polarizing plates380A to380C, and reflect light (S-polarized light) having any other polarization axis. Specifically, the reflective polarizing plate410A transmits P-polarized red light Lr from the polarizing plate380A in a direction of the reflective liquid crystal panel420A. The reflective polarizing plate410B transmits P-polarized blue light Lb from the polarizing plate380B in a direction of the reflective liquid crystal panel420B. The reflective polarizing plate410C transmits P-polarized green light Lg from the polarizing plate380C in a direction of the reflective liquid crystal panel420C. In addition, the reflective polarizing plate410A reflects S-polarized red light Lr from the reflective liquid crystal panel420A to cause the S-polarized red light Lr to be incident on the dichroic prism430. The reflective polarizing plate410B reflects S-polarized blue light Lb from the reflective liquid crystal panel420B to cause the S-polarized blue light Lb to be incident on the dichroic prism430. The reflective polarizing plate410C reflects S-polarized green light Lg from the reflective liquid crystal panel420C to cause the S-polarized green light Lg to be incident on the dichroic prism430.

The reflective liquid crystal panels420A to420C respectively perform spatial modulation of red light Lr, blue light Lb, and green light Lg.

The dichroic prism430synthesizes incident red light Lr, incident blue light Lb, and incident green light Lg, and outputs synthesized light toward the projection optical system500.

The projection optical system500includes, for example, multiple lenses, or the like. The projection optical system500expands light emitted from the image-forming unit400, and projects the expanded light on a screen600, or the like.

Configuration Example 2 of Projection-Type Display Apparatus

FIG.16is a schematic view of another example (a projection-type display apparatus6B) of the overall configuration of the optical system configuring the projection-type display apparatus6. The projection-type display apparatus6B is a projection-type display apparatus of a transmissive 3LCD type that performs light modulation using a transmissive liquid crystal panel (LCD).

The projection-type display apparatus6B includes, for example, the light source device1, an image-generating system700including an illumination optical system710and an image-generating section730, and the projection optical system500in order.

The illumination optical system710includes, for example, an integrator element711, a polarization conversion element712, and a condensing lens713. The integrator element711includes a first fly-eye lens711A and a second fly-eye lens711B. The first fly-eye lens711A includes multiple microlenses arranged two-dimensionally, and the second fly-eye lens711B includes multiple microlenses arranged to correspond one by one to the respective microlenses of the first fly-eye lens711A.

Light (parallel light) incident on the integrator element711from the light source device1is divided into multiple light fluxes by the microlenses of the first fly-eye lens711A, and an image of each of the light fluxes is formed on a corresponding one of the microlenses of the second fly-eye lens711B. Each of the microlenses of the second fly-eye lens711B serves as a secondary light source, and multiple parallel light beams having uniform luminance are irradiated as incident light to the polarization conversion element712.

The integrator element711has a function of arranging incident light irradiated from the light source device1to the polarization conversion element712in a uniform luminance distribution as a whole.

The polarization conversion element712has a function of aligning a polarization state of incident light incident thereon through the integrator element711, or the like. The polarization conversion element712outputs emission light including the blue light Lb, the green light Lg, and the red light Lr through the lens, or the like, disposed on emission side of the light source device1, for example.

The illumination optical system710further includes a dichroic mirror714, a dichroic mirror715, a mirror716, a mirror717, a mirror718, a relay lens719, a relay lens720, a field lens721R, a field lens721G, a field lens721B, liquid crystal panels731R,731G, and731B as the image-generating section730, and a dichroic prism732.

The dichroic mirror714and the dichroic mirror715have properties of selectively reflecting color light in a predetermined wavelength region, and transmitting light in a wavelength region other than the predetermined wavelength region. For example, the dichroic mirror714selectively reflects the red light Lr. The dichroic mirror715selectively reflects the green light Lg of the green light Lg and the blue light Lb that have been transmitted through the dichroic mirror714. The remaining blue light Lb is transmitted through the dichroic mirror715. Thus, light (e.g., white multiplexed light Lw) emitted from the light source device1is separated into multiple color light beams having different colors.

The separated red light Lr is reflected by the mirror716, and becomes parallel through passing through the field lens721R, and thereafter is incident on the light crystal panel731R for red light modulation. The green light Lg becomes parallel through passing through the field lens721G, and thereafter is incident on the liquid crystal panel731G for green light modulation. The blue light Lb passes through the relay lens719, and is reflected by the mirror717, and further passes through the relay lens720, and is reflected by the mirror718. The blue light Lb reflected by the mirror718becomes parallel through passing through the field lens721B, and thereafter is incident on the liquid crystal panel731B for modulation of the blue light Lb.

The liquid crystal panels731R,731G, and731B are electrically coupled to an unillustrated signal source (e.g., a PC, etc.) that supplies an image signal including image information. The liquid crystal panels731R,731G, and731B modulate incident light for each pixel on the basis of supplied image signals of respective colors to respectively generate a red image, a green image, and a blue image. Modulated light beams of respective colors (formed images) are incident on the dichroic prism732to be synthesized. The dichroic prism732superimposes the light beams of respective colors incident in three directions on one another to synthesize the light beams, and outputs the synthesized light beams toward the projection optical system500.

The projection optical system500includes, for example, multiple lenses and the like. The projection optical system500expands light emitted from the image-generating system700, and projects the light onto the screen600.

Application Example 2

FIG.17schematically illustrates a configuration of a display system according to Application Example 2.FIG.18illustrates a functional configuration of the display system according to Application Example 2. The display system includes a wristband-type terminal (a wristband-type information processor)8and a smartphone (external apparatus)7.

The smartphone7is, for example, an information processor that operates in cooperation with the wristband-type terminal8, and has a function of transmitting an image to be projected or displayed to the wristband-type terminal8and of receiving information indicating a user operation. Specifically, the smartphone7transmits an image indicating a graphical user interface (GUI) to the wristband-type terminal8, and receives a user operation signal for the GUI. Then, the smartphone7performs processing in response to the received user operation, and transmits an image indicating the GUI updated in response to the processing to the wristband-type terminal8.

It is to be noted that the external apparatus operating in cooperation with the wristband-type terminal8is not limited to the smartphone, but may be any other information processor, for example, a digital still camera, a digital video camera, PDA (Personal Digital Assistants), a PC (Personal Computer), a notebook PC, a tablet terminal, a mobile phone terminal, a portable music player, a portable video processor, or a portable gaming machine.

The wristband-type terminal8includes, for example, a display unit810, and the projection-type display apparatus6including the light source device (e.g., light source device1) of the foregoing embodiment, or the like, and is used to be worn on a wrist, or the like of a user using a band part8a. The band part8ais configured by leather, metal, fiber, rubber or the like, for example, similarly to a wristwatch band.

The wristband-type terminal8further includes, for example, a control unit820, a communication unit830, an imaging unit840, an operation unit850, and a sensor unit860, as illustrated inFIG.18. In addition, the wristband-type terminal8is coupled to the smartphone7by wireless communication, and operates in cooperation with the smartphone7. For example, an image received from the smartphone7placed in a pocket or the like of clothing of the user is able to be displayed on the display unit810or projected onto a palm or the like of the user using the projection-type display apparatus6.

The display unit810displays an image (a still image or a moving image) under the control of the control unit820, and includes, for example, an LCD, an OLED (Organic Light-Emitting Diode), or the like. The display unit810is configured integrally with the operation unit850, for example, and functions as a so-called touch panel.

The communication unit830transmits and receives signals (such as image signals and user operation signals) to and from the smartphone7. Examples of a communication method include methods of wireless, Bluetooth (registered trademark), WiHD (Wireless High Definition), WLAN (Wireless Local Area Network), Wi-Fi (Wireless Fidelity: registered trademark), NFC (Near Field communication), infrared communication, and the like. In addition, other than those mentioned above, communication using radio waves in 3G/LTE (Long Term Evolution) or a millimeter wave band may be performed.

The imaging unit840includes, for example, a lens section including an imaging lens, an aperture, a zoom lens, a focus lens, and the like, a drive section that drives the lens section to perform a focusing operation or a zooming operation, and a solid-state imaging element that generates an imaging signal on the basis of imaging light obtained through the lens section. The solid-state imaging element is configured by, for example, a CCD (Charge Coupled Device) or CMOS (Complementary Metal Oxide Semiconductor) image sensor, etc. The imaging unit840outputs, to the control unit820, data of a captured image having been turned into a digital signal.

The operation unit850has a function of receiving an input signal (user operation signal) from the user. For example, the operation unit850is configured by buttons, a touch sensor, or a trackball. Here, the operation unit850is configured integrally with the display unit810, thereby functioning as a touch panel. This operation unit850outputs the inputted user operation signal to the control unit820.

The sensor unit860has a function of acquiring information regarding a user's motion or state. For example, the sensor unit860is provided with a camera that is intended to capture an image of a user's face or eye, or the hand to which the wristband-type terminal8is attached. Other than those described above, for example, the sensor unit860may include a camera with a depth detecting function, a microphone, a GPS, an infrared sensor, a ray sensor, a myoelectric sensor, a nerve sensor, a sphygmus sensor, a body heat sensor, a gyroscope sensor, an acceleration sensor, a touch sensor, or the like. Among these, the myoelectric sensor, the nerve sensor, the sphygmus sensor, and the body heat sensor may be provided in the band part8a. Such a sensor unit860is able to perform a sensing operation near the user's hand, thereby allowing for accurate detection of the motion of the hand. The sensor unit860senses a user's motion or state, and then outputs information indicating the sensing result to the control unit820.

The control unit820functions as a processor and a controller, and controls an overall operation inside the wristband-type terminal8in accordance with various programs. The control unit820is configured by a CPU (Central Processing Unit) or a microphone processor, for example. This control unit820may include, for example, ROM (Read Only Memory) that stores programs, arithmetic parameters, or the like to be used and RAM (Random Access Memory) that temporarily stores parameters or the like varying as appropriate.

The control unit820includes a recognition section821and a detection section822, for example, which allow for gesture input. The recognition section821has a function of recognizing the motion of the user's hand to which the band part8ais attached. Specifically, the recognition section821recognizes the motion of the hand through, for example, motion recognition and image recognition using an image (e.g., image of captured user's hand) inputted from the sensor unit860. The control unit820performs various types of processing, such as screen transition, on the basis of the recognition result from the recognition section821. The detection section822has a function of detecting a user operation on an image Y1projected by the projection-type display apparatus6. For example, the detection section822detects a user operation on the projected image, such as a flick or a touch. The control unit820transmits information indicating the user operation detected by the detection section822to the smartphone7. Then, the smartphone7performs processing in accordance with the user operation. This enables the wristband-type terminal8to execute, on the display unit810or the user's hand, a function (image transition, etc.) that is similar to a function to be performed in a case where the user performs an operation (a flick or a touch, etc.) on the touch panel of the smartphone7. For example, when the user flicks the projected image Y1vertically, the wristband-type terminal8is able to perform a function of scrolling the projected image Y1.

It is to be noted that, in the example ofFIG.17, a map image generated in the smartphone7using a GPS (Global Positioning System) function is displayed on the display unit810, and is projected as the projected image Y1. The display unit810has a limitation on its physical size, because the wristband-type terminal8is intended to achieve portability; in some cases, it is difficult for the user to see an image displayed on the display unit810. In such cases, the projection-type display apparatus6is used to project the image onto the hand in an expanded manner, for example, to an inch size equivalent to that of the smartphone7, thus making it possible to enhance the visibility of the image. In addition, it is possible for the user to see an image, on his or her hand, which is received from the smartphone7being still placed in a pocket or a bag, thus leading to improvement in the usability.

In a display system as described above, in a case of adjusting the color balance of illumination light from the light source device1, or in a case of utilizing infrared light in the sensor unit860, for example, it is possible to suitably use the light source device (e.g., light source device1) in the foregoing embodiments and the like.

Application Example 3

FIG.19schematically illustrates a configuration of a display system according to Application Example 3. This display system includes the projection-type display apparatus6provided with the light source device (e.g., light source device1) in the foregoing embodiments and the like, a laser pointer910, and a PC920that outputs a content to be projected to the projection-type display apparatus6. Examples of the content to be projected include a diagram, a text, any other various graphic image, a map, and a website.

The laser pointer910has a function of irradiating laser light (invisible light or visible light) in accordance with a user's pressing operation of an operation button910a. It may be possible for the user to use the laser pointer910to irradiate an image projected onto a screen930with the laser light. This enables the user to, for example, make a presentation while pointing to an irradiation position P in line with a referenced area.

The PC920generates image data to be projected, and transmits this image data to the projection-type display apparatus6in a wired or wireless manner to control the projection. InFIG.19, a notebook PC is illustrated as an example thereof; however, the PC920is not limited to the notebook PC, and may be a desktop PC or a server on a network (cloud).

In this application example, the projection-type display apparatus6includes an imaging unit that projects an image received from the PC920onto the screen930, and recognizes the irradiation of the projected image with the laser pointer910. The imaging unit enables detection using the laser light (invisible light or visible light) with which the screen930is irradiated. This imaging unit may be mounted either inside or outside the projection-type display apparatus6. By using the light source device (e.g., light source device1) in the foregoing embodiments and the like in the projection-type display apparatus6, it is possible to output synthesized light beams of multiple wavelengths by using a single light source, as described above. This eliminates the need to separately provide a light source for projection and a light source for imaging, thus making it possible to achieve simplification and compactness of the entire apparatus.

Although the description has been given above of the first to third embodiments, Modification Examples 1 to 7, and application examples, the present disclosure is not limited to the foregoing embodiments and the like, and may be modified in a wide variety of ways. For example, the arrangement, the number, or the like of the components (e.g., the light source sections11and15, the wavelength conversion section, the polarization separation element13, the color separation element14, the light-condensing optical system16, etc.) of the optical system exemplified in the foregoing embodiments and the like are merely exemplary; not all the components need to be provided, and other components may be further provided.

Further, the projection display apparatus and the display system that have been described as application examples of the light source device (e.g., the light source device1) in the foregoing embodiments and the like are exemplary, and are not limited to those described above. For example, the light source device of the disclosure is also applicable to a night vision apparatus (night vision system) that uses infrared light.

Further, as the projection display apparatus according to the present disclosure, an apparatus other than the foregoing projection-type display apparatus6(6A or6B) may be configured. In addition, the light source device according to the present disclosure may be used for an apparatus other than the projection display apparatus. For example, the light source device1according to the present disclosure may be used for illumination, and is applicable to a light source for a headlight of an automobile or a light source for lighting up, for example.

It is to be noted that the effects described herein are merely illustrative and are not limited to the description, and may have other effects.

The present technology may also have the following configurations. According to the present technology having the following configurations, a polarization separation element that separates light in a second wavelength region emitted from a wavelength conversion section on the basis of polarization is provided between a first light source section and the wavelength conversion section, and a color separation element that performs separation also on the basis of a wavelength region of incident light is provided between the polarization separation element and a first light source section, thereby improving utilization efficiency of fluorescence (light in the second wavelength region) emitted from the wavelength conversion section. Thus, it is possible to improve efficiency in extraction of light with uniform polarization.

A light source device including:

a first light source section that emits light in a first wavelength region;

a wavelength conversion section disposed on an optical path of the light in the first wavelength region, the wavelength conversion section being excited by the light in the first wavelength region emitted from the first light source section to emit light in a second wavelength region different from the first wavelength region;

a polarization separation element that is disposed between the first light source section and the wavelength conversion section, and separates incident light on the basis of polarization;

and a color separation element that is disposed between the first light source section and the polarization separation element, and separates incident light on the basis of a wavelength region.

The light source device according to (1), further including a second light source section that emits light in a third wavelength region different from the light in the second wavelength region.

The light source device according to (2), in which the second light source section includes multiple light sources that emit light beams in wavelength regions different from one another.

The light source device according to any one of (1) to (3), in which the polarization separation element also serves as an optical path synthesizing element.

The light source device according to any one of (2) to (4), in which the light in the second wavelength region and the light in the third wavelength region are subjected to optical path synthesis by the polarization separation element.

The light source device according to any one of (2) to (5), in which

the first light source section and the second light source section are disposed to be opposed to each other in one direction,

the polarization separation element is disposed between the first light source section and the second light source section, and

the wavelength conversion section is disposed to be opposed to the polarization separation element in another direction orthogonal to the one direction.

The light source device according to any one of (2) to (5), in which

the first light source section and the wavelength conversion section are disposed to be opposed to each other in one direction,

the polarization separation element is disposed between the first light source section and the wavelength conversion section, and

the second light source section is disposed to be opposed to the polarization separation element in another direction orthogonal to the one direction.

The light source device according to any one of (1) to (7), in which the polarization separation element includes a plate-type or prism-type polarization beam splitter.

The light source device according to any one of (1) to (8), in which the color separation element includes a dichroic mirror.

The light source device according to any one of (1) to (9), further including a light-condensing optical system between the wavelength conversion section and the polarization separation element.

The light source device according to (10), in which the light-condensing optical system includes a collimator lens.

The light source device according to any one of (1) to (11), further including a polarization conversion element disposed between the wavelength conversion section and the polarization separation element, the polarization conversion element changing deflection of the light in the second wavelength region reflected by the polarization separation element.

The light source device according to (12), in which the polarization conversion element includes a depolarization element.

The light source device according to (12), in which the polarization conversion element includes a phase difference plate.

The light source device according to any one of (1) to (14), in which the polarization separation element and the color separation element are integrated.

The light source device according to any one of (1) to (15), in which the wavelength conversion section is of a reflective type that emits the light in the second wavelength region in an incident direction of the light in the first wavelength region.

The light source device according to any one of (1) to (16), in which the wavelength conversion section includes a phosphor and a support substrate that supports the phosphor.

The light source device according to (17), in which the wavelength conversion section further includes a drive part that rotates the support substrate.

The light source device according to any one of (1) to (18), further including at least one of a first angle adjustment mechanism that adjusts an angle of the polarization separation element or a second angle adjustment mechanism that adjusts an angle of the color separation element.

A projection-type display apparatus including:

a light source device;

a light modulation element that modulates light emitted from the light source device; and

a projection optical system that projects light from the light modulation element,the light source device includinga first light source section that emits light in a first wavelength region,a wavelength conversion section disposed on an optical path of the light in the first wavelength region, the wavelength conversion section being excited by the light in the first wavelength region emitted from the first light source section to emit light in a second wavelength region different from the first wavelength region,a polarization separation element that is disposed between the first light source section and the wavelength conversion section, and separates incident light on the basis of polarization, anda color separation element that is disposed between the first light source section and the polarization separation element, and separates incident light on the basis of a wavelength region.

This application claims the benefit of Japanese Priority Patent Application JP2019-230027 filed with the Japan Patent Office on Dec. 20, 2019, the entire contents of which are incorporated herein by reference.