JP2019194673A - Wavelength conversion element, phosphor wheel, light source device, and projection type image display device - Google Patents

Abstract

Provided is a wavelength conversion element that is improved in conversion efficiency to fluorescent light and thermal efficiency.
A first wavelength conversion element 101 includes a first phosphor region 111, a second phosphor region 112, and a third phosphor region 113 made of phosphor particles 111a, 112a, and 113a having different particle sizes. The phosphor region is composed of three layers. The particle size of the phosphor particles 112a constituting the second phosphor region arranged in the middle is such that the phosphor particles 111a in the first phosphor region 111 on the front surface side and the phosphor particles in the third phosphor region 113 on the back surface side. It is smaller than the particle size of 113a.
[Selection] Figure 1

Description

  The present disclosure relates to a wavelength conversion element and a phosphor wheel used, for example, in a light source device of a projection display apparatus.

  Patent Document 1 includes a base material, a phosphor region that contains a first phosphor that emits light when incident excitation light enters, and a second phosphor (thermally conductive material). A wavelength conversion element including an adhesive layer that adheres to a body region is disclosed.

JP 2018-36457 A

  The present disclosure provides a wavelength conversion element that is improved in conversion efficiency to fluorescent light and thermal efficiency.

  The wavelength conversion element according to the present disclosure includes a first phosphor region and phosphor particles having a particle size different from the particle size of the phosphor particles located in the first phosphor region and disposed in the thickness direction of the first phosphor region. A second phosphor region located.

  The wavelength conversion element of the present disclosure is effective for improving the conversion efficiency to fluorescent light and the thermal efficiency.

The figure which shows the structure of the wavelength conversion element of Embodiment 1. The figure which shows the structure of the 1st fluorescent substance wheel using the ring-shaped 1st wavelength conversion element of Embodiment 1. FIG. The figure which shows the structure of the 2nd fluorescent substance wheel using the 1st wavelength conversion element of the segment shape of Embodiment 1. FIG. The figure which shows the structure of the 3rd fluorescent substance wheel using the ring-shaped 1st wavelength conversion element of Embodiment 1. FIG. The figure which shows the structure of the phosphor wheel using the ring-shaped 2nd wavelength conversion element of Embodiment 1. FIG. The figure which shows the structure of the wavelength conversion element concerning a comparative example The figure which shows the structure of the 1st fluorescent substance wheel using the ring-shaped wavelength conversion element concerning a comparative example. The figure which shows the structure of the wavelength conversion element of Embodiment 2. The figure which shows the structure of the 1st and 2nd fluorescent substance wheel using the ring-shaped 1st and 2nd wavelength conversion element of Embodiment 2, respectively. The figure which shows the structure of the 3rd and 4th fluorescent substance wheel using the 1st and 2nd wavelength conversion element of the ring shape of Embodiment 2, respectively. The figure which shows the structure of the 1st light source device using the 1st fluorescent substance wheel of Embodiment 1. FIG. FIG. 5 is a diagram illustrating a configuration of a projection display apparatus using the first light source device of the first embodiment. The figure which shows the structure of the 2nd light source device using the 2nd fluorescent substance wheel of Embodiment 1. FIG. FIG. 5 is a diagram showing a configuration of a projection display apparatus using the second light source device of the first embodiment. The figure which shows the structure of the 3rd light source device using the 3rd fluorescent substance wheel of Embodiment 1. FIG. The figure which shows the structure of the projection type video display apparatus using the 3rd light source device of Embodiment 1. FIG. The figure which shows the structure of the wavelength conversion element of Embodiment 3.

  Hereinafter, embodiments will be described in detail with reference to the drawings as appropriate. However, more detailed description than necessary may be omitted. For example, detailed descriptions of already well-known matters and repeated descriptions for substantially the same configuration may be omitted. This is to avoid the following description from becoming unnecessarily redundant and to facilitate understanding by those skilled in the art.

  The accompanying drawings and the following description are provided to enable those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter described in the claims.

(Embodiment 1)
[1-1-1-1. Configuration of wavelength conversion element]
Hereinafter, the configuration of the wavelength conversion element in the first embodiment will be described in detail. 1A and 1B show the wavelength conversion element according to the first embodiment. FIG. 1A is a cross-sectional view of the first wavelength conversion element, and FIG. 1B is a cross-sectional view of the second wavelength conversion element. FIG. 1C is a plan view of a phosphor ring formed using the first or second wavelength conversion element.

  The wavelength conversion element 101 which is the first wavelength conversion element of the first embodiment shown in FIG. 1A includes a first phosphor region 111 made of phosphor particles 111a and a second phosphor made of phosphor particles 112a. The region 112 and the third phosphor region 113 composed of the phosphor particles 113a are composed of three layers of phosphor regions. As shown in FIG. 1A, phosphor particles having different particle diameters are arranged in the thickness direction of the phosphor region. Here, the fluorescence constituting the second phosphor region 112 arranged in the middle is arranged. The particle size of the body particles 112a is such that the phosphor particles 111a of the first phosphor region 111 on the front surface side (upper side of FIG. 1A) and the third fluorescence on the back surface side (lower side of FIG. 1A). It is smaller than the particle size of the phosphor particles 113a in the body region 113.

  Here, the phosphor particles 111a in the first phosphor region 111 and the phosphor particles 113a in the third phosphor region 113 may be different or the same. The particle size of the phosphor particles is selected from a range of several μm depending on the application and function. For example, the difference in particle size between the phosphor particles 111a and 113a having a large particle size and the phosphor particles 112a having a small particle size. Is about 1/5 to 1/10 of the particle size. In the following description of the embodiment, the relationship between the large particle size and the small particle size of the phosphor particles is the same. In addition, about the said particle size, it is an example and is not limited to the value.

  The wavelength conversion element 102, which is the second wavelength conversion element of the first embodiment shown in FIG. 1B, includes a first phosphor region 121 composed of phosphor particles 121a and a second phosphor composed of phosphor particles 122a. The third phosphor region 123 composed of the region 122 and the phosphor particles 123a is composed of three layers of phosphor regions that are stacked with a binder 124 such as silicone interposed therebetween. As shown in FIG. 1B, phosphor particles having different particle diameters are arranged in the thickness direction of the phosphor region. Here, the fluorescence constituting the second phosphor region 122 arranged in the middle is arranged. The particle size of the body particles 122a is such that the phosphor particles 121a of the first phosphor region 121 on the front surface side (upper side of FIG. 1B) and the third fluorescence on the back surface side (lower side of FIG. 1B). It is smaller than the particle size of the phosphor particles 123a in the body region 123.

  Here, the phosphor particles 121a in the first phosphor region 121 and the phosphor particles 123a in the third phosphor region 123 may be different or the same.

  As shown in FIG. 1C, the wavelength conversion elements 101 and 102 have a ring shape, but the phosphor ring may have a segment shape in which a part of the ring is missing, or a polygon such as a rectangle. It may be in shape.

[1-1-1-2. Configuration of phosphor wheel using wavelength conversion element]
First, FIG. 2 shows a configuration of a first phosphor wheel using the first wavelength conversion element of the first embodiment, and FIG. 2A is a plan view of the first phosphor wheel. 2 (b) is a sectional view of the first phosphor wheel.

  Here, a case will be described in which the wavelength conversion element is configured as a phosphor ring as shown in FIG.

  The phosphor wheel 1 as the first phosphor wheel includes a ring-shaped wavelength conversion element 101 having an antireflection film 103 provided on the surface, and a substrate 105 having a reflection layer 106 provided on the surface. And a ring-shaped wavelength conversion element 101 is provided with a silicone layer 104 filled with contained particles 141 that improve thermal conductivity and reflectance.

  As described above, the wavelength conversion element 101 includes phosphor particles 111a, 112a, and 113a having different particle diameters, and the particle diameters of the phosphor particles differ in the thickness direction of the phosphor region. Here, the particle diameters of the phosphor particles 111a on the surface of the antireflection film 103 side and the phosphor particles 113a on the substrate 105 side are larger than the phosphor particles 112a in the center as viewed in the thickness direction. A motor mounting hole 107 is provided in the substrate 105 of the phosphor wheel 1.

  Next, the structure of the 2nd fluorescent substance wheel using the 1st wavelength conversion element of Embodiment 1 is demonstrated. Here, unlike the phosphor wheel 1 shown in FIG. 2, a case where the phosphor wheel is configured using a segment shape in which a part of the phosphor ring shown in FIG. To do.

  FIG. 3 shows a configuration of a second phosphor wheel using the first wavelength conversion element of the first embodiment. FIG. 3A is a plan view of the second phosphor wheel, and FIG. 3B is a cross-sectional view of the second phosphor wheel 3.

  The phosphor wheel 3 as the second phosphor wheel is provided with an antireflection film 303 on the surface, a segment-shaped wavelength conversion element 101 having a missing portion, and a reflective layer 306 on the surface, corresponding to the missing portion. And a substrate 305 provided with an opening 308 in a portion to be provided. The segment-shaped wavelength conversion element 101 and the opening 308 are arranged at the same distance in the radial direction from the rotation center O of the phosphor wheel 3. A motor mounting hole 307 is provided in the substrate 305. Further, a silicone layer 304 filled with contained particles 341 that improve thermal conductivity and reflectance is provided between the reflective layer 306 and the segment-shaped wavelength conversion element 101.

  As described above, the wavelength conversion element 101 includes phosphor particles 111a, 112a, and 113a having different particle diameters, and the particle diameters of the phosphor particles differ in the thickness direction of the phosphor region. Here, the particle diameters of the phosphor particles 111a on the surface of the antireflection film 303 and the phosphor particles 113a on the substrate 305 side are larger than the phosphor particles 112a in the center as viewed in the thickness direction. In other words, the particle size of the phosphor particles 112a constituting the phosphor region arranged in the middle of the wavelength conversion element is smaller than the particle size of the phosphor particles 111a and 113a constituting the other two phosphor regions. .

  Next, the 3rd fluorescent substance wheel using the 1st wavelength conversion element of Embodiment 1 is demonstrated. FIG. 4 shows a configuration of a third phosphor wheel using the first wavelength conversion element of the first embodiment. 4A is a plan view of the third phosphor wheel, and FIG. 4B is a cross-sectional view taken along line 4b-4b shown in FIG. 4A.

  The phosphor wheel 4 as the third phosphor wheel includes a wavelength conversion element 101 having a reflection film 408 provided on a part of the surface of a phosphor ring having an antireflection film 403 provided on the surface, and a reflection layer provided on the surface. And a substrate 405 provided with 406. A motor mounting hole 407 is provided in the substrate 405. Between the reflective layer 406 and the wavelength conversion element 101, a silicone layer 404 filled with contained particles 441 that improve thermal conductivity and reflectance is provided.

  As described above, the wavelength conversion element 101 includes phosphor particles 111a, 112a, and 113a having different particle diameters, and the particle diameters of the phosphor particles differ in the thickness direction of the phosphor region. Here, the particle diameters of the phosphor particles 111a on the surface of the antireflection film 303 side and the phosphor particles 113a on the substrate 305 side are larger than the phosphor particles 112a in the center as viewed in the thickness direction. In other words, the particle size of the phosphor particles 112a constituting the phosphor region arranged in the middle of the wavelength conversion element 101 is larger than the particle size of the phosphor particles 111a and 113a constituting the other two phosphor regions. small.

  3 and FIG. 4, the single wavelength conversion element 101 is used. However, a plurality of wavelength conversion elements having different wavelength regions of fluorescence to be wavelength-converted may be used. In this case, the wavelength conversion element 101 may be used as at least one of the plurality of wavelength conversion elements.

  The phosphor wheels 3 and 4 shown in FIGS. 3 and 4 each have one opening 308 and one reflection film 408, but may be configured using a plurality of openings and a plurality of reflection films. .

  Next, the structure of the phosphor wheel using the second wavelength conversion element of Embodiment 1 will be described. FIG. 5 shows a configuration of a phosphor wheel using the second wavelength conversion element of the first embodiment. FIG. 5A is a plan view of the phosphor wheel, and FIG. 5B is a cross-sectional view of the phosphor wheel. The phosphor wheel 5 in FIG. 5 uses a wavelength conversion element 102 shown in FIG. 1B instead of the wavelength conversion element 101 shown in FIG.

  The phosphor wheel 5 is filled with contained particles 541 that improve thermal conductivity and reflectivity between the wavelength conversion element 102 having the antireflection film 503 provided on the surface and the substrate 505 having the reflection layer 506 provided on the surface. A silicone layer 504 is provided. A motor mounting hole 507 is provided in the substrate 505.

  As described above, the wavelength conversion element 102 includes the phosphor particles 121a, 122a, and 123a having different particle diameters and the binder 124 that is, for example, silicone, and the particle diameter of the phosphor particles is increased in the thickness direction of the phosphor region. Different. Here, the phosphor particles 121a on the antireflection film 503 side of the surface and the phosphor particles 123a on the substrate 505 side are larger than the phosphor particles 122a in the center as viewed in the thickness direction. In other words, the particle size of the phosphor particles 122a constituting the second phosphor region 122 disposed in the middle of the wavelength conversion element 102 is the particle size of the phosphor particles 121a and 123a constituting the other two phosphor regions. Smaller than the diameter.

  In the case where the wavelength conversion element 102 is used, a segment shape like the phosphor wheel 3 shown in FIG. 3 can be adopted as in the case where the wavelength conversion element 101 is used, and the fluorescence shown in FIG. A reflective film may be provided on a part of the surface of the phosphor ring like the body wheel 4.

[1-1-2. Effect etc.]
6 is a configuration diagram of a wavelength conversion element according to a comparative example of the present disclosure. FIG. 6A and FIG. 6B are cross-sectional views of the wavelength conversion element, and FIG. It is a top view of a conversion element.

  As shown in FIG. 6A, when the wavelength conversion element 201 is formed only with the phosphor region 211 composed of phosphor particles 211a having a large particle size, (1) surface reflection is reduced. 2) It has the characteristics that the scattering property increases, and (3) the thermal conductivity increases. Conversely, as shown in FIG. 6B, when the wavelength conversion element 202 is formed only with the phosphor region 221 composed of phosphor particles 221a having a small particle diameter, (1) surface reflection increases. (2) The scattering property is reduced, and (3) the thermal conductivity is lowered.

  First, regarding surface reflection, excitation light absorbed by the phosphor increases when there is less surface reflection. Therefore, if the phosphor has the same quantum efficiency, the fluorescence emitted after wavelength conversion is increased. That is, the conversion efficiency (fluorescence efficiency) increases when the particle diameter is larger than when the particle diameter is smaller.

  Next, with respect to the scattering property, the excitation light guides through the phosphor particles, and the wavelength is converted to emit fluorescence. For this reason, even when light of the same spot size is incident, the spot size of light emission is larger when the particle diameter is larger than when it is smaller. If the spot size for light emission increases, the capture efficiency in the light guide system in the subsequent stage or the rod optical system decreases. That is, the larger the particle size, the lower the efficiency of taking in the optical system at the latter stage compared to the smaller particle size.

  Finally, there is a greater interfacial thermal resistance between adjacent particles than inside the particles. For this reason, in the case of the same phosphor thickness, the larger the particle diameter of the phosphor particles, the smaller the number of existing interfaces, while the smaller the number of interfaces, the smaller the thermal resistance value. The rate increases. Since the phosphor has a characteristic that the fluorescence characteristic decreases as the temperature rises, the conversion efficiency increases as the particle diameter increases with respect to the smaller particle diameter.

  In summary, the larger the particle size, the higher the absorption efficiency based on surface reflection, the lower the capture efficiency (coupling efficiency) based on spot size, and the higher the conversion efficiency that changes with temperature. .

  The efficiency of the light source device and the projection-type image device has the following three factors: (1) absorption efficiency based on surface reflection, (2) capture efficiency (coupling efficiency) based on spot size, and (3) conversion efficiency that varies depending on temperature. It can be calculated by product.

  As described above, when the particle size is large, (2) the uptake efficiency (binding efficiency) based on the spot size decreases, and conversely, when the particle size is small, (1) the absorption efficiency based on surface reflection (3 ) Two of the conversion efficiencies that change with temperature are reduced.

  When the phosphor region is formed by only the phosphor particles having a large particle diameter or the phosphor particles having a small particle diameter as described above, the wavelength conversion is performed with any of the above (1) to (3) being lowered. An element, a phosphor wheel using the element, a light source device, and a projection-type image display device are configured.

  FIG. 7 is a diagram showing a configuration of the phosphor wheel 2 using the phosphor ring using the wavelength conversion element according to the comparative example. FIG. 7A is a plan view of the phosphor wheel 2, and FIG. (B) And (c) shows sectional drawing of the fluorescent substance wheel 2, respectively.

  The effects of the present disclosure will be described with reference to the phosphor wheel 1 shown in FIG. 2B and the phosphor wheel 2 shown in FIG. The functions of the antireflection film 203, the silicone layer 204, the substrate 205, the reflection layer 206, and the motor mounting hole 207 of the phosphor wheel 2 shown in FIG. 7 are the same as those of the phosphor wheel 1 shown in FIG. Is omitted.

  In the phosphor wheel 1 shown in FIG. 2B, excitation light L that is a blue laser is irradiated from the antireflection film 103 side provided on the surface of the phosphor wheel 1. When the excitation light L passes through the antireflection film 103 and enters the wavelength conversion element 101, the excitation light L enters the phosphor particles 111a, 112a, and 113a in this order from the surface of the wavelength conversion element 101. Excites and emits fluorescence. Excitation light that has not been absorbed by the phosphor particles 111a, 112a, and 113a reaches the adhesive layer made of the silicone layer 104 provided on the substrate 105 side of the wavelength conversion element 101, and reflects the reflectance provided in the adhesive layer. The light is reflected by the high contained particles 141 or the reflective layer 106 thereunder, and the traveling direction of light is changed again to the wavelength conversion element 101 side. The excitation light reflected by the reflective layer 106 and incident on the wavelength conversion element 101 enters the phosphor particles 113a, 112a, 111a in this order and is converted into fluorescence.

  It has been found that the efficiency with which the excitation light is absorbed by the wavelength conversion element (hereinafter referred to as “absorption efficiency”) depends on the filling rate of the phosphor particles and the particle size of the phosphor particles. Since the filling rate of the phosphor particles can be optimized so as to be maximized regardless of the particle diameter, the absorption efficiency depends on the particle diameter of the phosphor particles. For example, in the case of a wavelength conversion element composed of phosphor particles having different particle diameters as shown in FIGS. 6 (a) and 6 (b), FIG. The absorption efficiency of the wavelength conversion element 201 of a) is higher than that of the wavelength conversion element 202 of FIG. 6B configured by phosphor particles having a smaller particle diameter. In the case of the phosphor wheel 1 using the wavelength conversion element 101 whose cross section is shown in FIG. 2B, a high absorption rate can be realized by enlarging the phosphor particles 111a on the incident side of the excitation light. it can.

  The light converted from excitation light into fluorescence is emitted from the phosphor particles 111a, 112a, and 113a in all directions. A part of the fluorescence emitted to the side opposite to the substrate 105 side is absorbed by the phosphor particles 111a, 112a, 113a and converted into heat, but other light passes through the antireflection film 103. Is emitted.

  On the other hand, the fluorescence emitted to the substrate 105 side is reflected by the adhesive layer of the silicone layer 104 containing the particles 141 having a high reflectance or the reflection layer 106 provided on the wavelength conversion element 101 side of the substrate 105, The traveling direction is changed, and the light is emitted to the side opposite to the substrate 105. A part of the fluorescence emitted to the side opposite to the substrate 105 is absorbed by the phosphor particles 111a, 112a, 113a and converted into heat, and the remaining light passes through the antireflection film 103 and is emitted. .

  At this time, the fluorescence converted in wavelength by the phosphor particles 111a, 112a, and 113a emits fluorescence from the outer surface of the phosphor particles 111a, 112a, and 113a. At this time, in the case of the phosphor particles having different particle diameters as shown in FIGS. 6A and 6B, the wavelength conversion of FIG. 6A composed of the phosphor particles having a large particle diameter. The element 201 has a larger fluorescent emission spot than the wavelength conversion element 202 shown in FIG. 6B, which is composed of phosphor particles having a smaller particle diameter. The efficiency that can be captured by the latter optical system (hereinafter referred to as “coupling efficiency”) varies depending on the size of the fluorescent spot. When the maximum fluorescent spot that can be captured by the latter optical system is exceeded, the larger the fluorescent spot, the more efficient the coupling efficiency. Deteriorate. For this reason, in order to optimize the coupling efficiency, it is necessary to reduce the particle size of the phosphor particles. In the case of the phosphor wheel 1 using the first wavelength conversion element 101 whose cross section is shown in FIG. 2B, phosphor particles 112a having a small particle size are provided in the middle portion in the thickness direction, which has a large influence on the spot size. By arranging, high coupling efficiency can be realized.

  Heat generated without being converted into fluorescence by the phosphor particles propagates to the periphery through the phosphor particles. Note that the phosphor has the characteristic of temperature quenching that the excitation light converted into fluorescence decreases as the temperature rises. Therefore, the lower the temperature, the higher the conversion efficiency. As shown in FIG. 2A, the temperature of the wavelength conversion element 101 can be lowered by transferring heat to the substrate 105 having the largest surface area in the phosphor wheel 1. It is necessary to increase the thermal conductivity of the conversion element 101 in the thickness direction, in other words, to reduce the thermal resistance. Here, among the wavelength conversion elements, the highest thermal resistance value is the interface resistance generated at the interface between the phosphor particles. Therefore, the thermal resistance as the wavelength conversion element is reduced by reducing the interface between the particles. The value goes down. That is, as described in the comparative example, the wavelength conversion element 201 in FIG. 6A configured with phosphor particles having a large particle size is the same as that in FIG. 6B configured with phosphor particles having a small particle size. The thermal resistance value is smaller than that of the wavelength conversion element 202. In the case of the phosphor wheel 1 using the wavelength conversion element 101 whose cross section is shown in FIG. 2B, by increasing the phosphor particles 113a on the substrate side in the thickness direction that greatly affects the thermal resistance value, The resistance value can be reduced, the temperature of the wavelength conversion element 101 can be lowered, the influence of temperature quenching can be reduced, and the fluorescence efficiency can be improved.

  As described above, the phosphor wheel 1 using the wavelength conversion element 101 whose cross section is shown in FIG. 2B has a large particle size of the phosphor particles 111a on the surface side in the thickness direction of the wavelength conversion element 101, and the intermediate By reducing the particle size of the phosphor particles 112a in the portion and increasing the particle size of the phosphor particles 113a on the substrate side, the absorption efficiency, the coupling efficiency, and the fluorescence efficiency are improved, and the absorption efficiency × the coupling efficiency × the fluorescence efficiency Can maximize the efficiency of the phosphor wheel.

  In the phosphor wheels 3 and 4 using the wavelength conversion element 101 shown in FIG. 3 and FIG. 4, respectively, as in the phosphor wheel 1 shown in FIG. Thus, the absorption efficiency is improved, the phosphor particles 112a having a small particle size in the middle part are used to improve the coupling efficiency, and the phosphor particles 113a having a large particle size on the substrate side are used to suppress the temperature rise and improve the fluorescence efficiency. For this reason, the efficiency of the phosphor wheel calculated | required by absorption efficiency x coupling efficiency x fluorescence efficiency can be maximized. In the phosphor wheel 5 using the wavelength conversion element 102 shown in FIG. 5 as well, as with the phosphor wheel using the wavelength conversion element 101, the absorption efficiency of the phosphor particles 121a having a large particle diameter from the surface of the wavelength conversion element 102 is increased. The phosphor efficiency is improved by the phosphor particles 122a in the middle portion, and the temperature rise is suppressed by the phosphor particles 123a on the substrate side, thereby improving the fluorescence efficiency. For this reason, the efficiency of the phosphor wheel calculated | required by absorption efficiency x coupling efficiency x fluorescence efficiency can be maximized.

  As described above, the wavelength conversion element having the configuration of the present embodiment determines the characteristics of the wavelength conversion element (1) absorption efficiency based on surface reflection, (2) uptake efficiency based on spot size (coupling efficiency) ), (3) It is possible to improve the conversion efficiency varying with temperature, and a wavelength conversion element with improved efficiency can be obtained.

[1-2. Light source device having phosphor wheel]
A configuration of a light source device using a phosphor wheel using the wavelength conversion element of the first embodiment will be described.

  FIG. 11 shows a first light source device using a first phosphor wheel using a ring-shaped wavelength conversion element as a light source device 9. Hereinafter, the light source device 9 will be described using the phosphor wheel 1 using the wavelength conversion element 101 shown in FIG.

  Laser light in a blue wavelength range emitted from a plurality of laser light sources 901 is collimated by a plurality of collimator lenses 902 provided corresponding to each of the laser light sources 901. The collimated blue light is incident on the convex lens 903 in the subsequent stage, the luminous flux width is reduced, the incident light is incident on the subsequent diffusion plate 904 and diffused, and the uniformity of the light is improved. The blue light whose light uniformity is improved is incident on the concave lens 905 at the subsequent stage to be converted into a parallel light beam.

  The blue light collimated by the concave lens 905 is incident on a mirror 906 having a spectral characteristic that is disposed at an inclination of about 45 degrees with respect to the optical axis, and is incident on the subsequent convex lens 907 without changing the traveling direction of the light. To do. The mirror 906 with spectral characteristics passes through the laser light source 901 and the blue light wavelength region emitted from the laser light source 921, and the phosphor wheel 1 converts the wavelength of the fluorescent light that is converted into the blue light from the laser light source 901 as excitation light. It has spectral characteristics that reflect light in the wavelength range.

  Here, it is assumed that the mirror 906 with spectral characteristics has spectral characteristics that focus on the wavelength characteristics of the blue light from the laser light source and the wavelength-converted fluorescence, but the blue light from the laser light source focuses on the polarization direction of the laser light source. By adjusting the polarization direction of the light to the same direction, the light having the wavelength range of the blue light from the laser light source and the light in the polarization direction can pass through and have spectral characteristics that pay attention to the wavelength characteristics of the wavelength-converted fluorescence. good.

  The blue light incident on the convex lens 907 is incident on the ring-shaped wavelength conversion element 101 provided on the subsequent phosphor wheel 1 in combination with the subsequent convex lens 908. The phosphor wheel 1 is provided with a motor 109 so that the blue excitation light condensed by the convex lenses 907 and 908 is incident on the ring-shaped wavelength conversion element 101 around the rotation axis. Has been placed.

  The blue light condensed on the wavelength conversion element 101 of the phosphor wheel 1 by the convex lenses 907 and 908 is wavelength-converted into fluorescence, and the light traveling direction is changed by 180 degrees, and the convex light 908 and 907 again. Incident light is incident in this order to be collimated. The wavelength-converted fluorescence here is combined with blue light emitted from a laser light source 921 to be described later, and the wavelength region is optimized so as to form white light, for example.

  The fluorescence emitted from the convex lens 907 and converted into parallel light enters the mirror 906 with spectral characteristics from the opposite direction. As described above, the spectroscopic mirror 906 has a characteristic of reflecting light in the fluorescent wavelength region, and thus changes the direction of the light by 90 degrees.

  Fluorescence whose light traveling direction is changed by 90 degrees with the mirror 906 having spectral characteristics is incident on the convex lens 909 at the subsequent stage.

  Further, the laser light in the blue wavelength region emitted from the plurality of laser light sources 921 is collimated by a plurality of collimator lenses 922 provided corresponding to each of the laser light sources 921. The collimated blue light enters the convex lens 923 at the subsequent stage, reduces the beam width thereof, enters the subsequent diffusion plate 924, is diffused, and the light uniformity is improved. The blue light whose light uniformity is improved is incident on the concave lens 925 at the subsequent stage and is converted into a parallel light beam.

  The blue light collimated by the concave lens 925 has a characteristic that the light in the wavelength region of the blue light emitted from the laser light source 921 passes, and the mirror 906 with spectral characteristics disposed at an inclination of about 45 degrees with respect to the optical axis. , And enters the subsequent convex lens 909 without changing the traveling direction of the light.

  The fluorescent light from the phosphor wheel 1 and the blue light from the laser light source 921 incident on the convex lens 909 are condensed and incident on a rod integrator 910 having an incident end disposed substantially at the condensing position of the convex lens 909. The light whose beam has been made uniform by the rod integrator is emitted from the exit end of the rod integrator.

  In the embodiment shown in FIG. 11, the mirror 906 with spectral characteristics is arranged at an angle of about 45 degrees with respect to the optical axis, but in order to maximize the spectral characteristics, the angle of the mirror 906 with spectral characteristics with respect to the optical axis. May have an angle different from about 45 degrees, and in that case, other components may be arranged in accordance with the angle.

  In FIG. 11, the spectroscopic mirror 906 is described as having a characteristic of transmitting light in the blue wavelength range and reflecting light in the fluorescent wavelength range. The arrangement of other components may be optimized as appropriate, assuming that the light has a characteristic of reflecting and transmitting light in the fluorescent wavelength region.

  Further, the laser light from the laser light source 901 may be light in the ultraviolet region instead of light in the blue wavelength region. In that case, the characteristics of the mirror 906 with spectral characteristics, the arrangement of other components, and the like may be optimized according to the wavelength region of the laser light of the laser light source 901.

  Next, a second light source device using a second phosphor wheel using a segment-shaped wavelength conversion element is shown as a light source device 11 in FIG. Hereinafter, the light source device 11 will be described using the phosphor wheel 3 using the wavelength conversion element 101 shown in FIG.

  Laser light in the blue wavelength region emitted from the plurality of laser light sources 1101 is collimated by a plurality of collimator lenses 1102 provided corresponding to each of the laser light sources 1101. The collimated blue light is incident on the convex lens 1103 at the subsequent stage, the luminous flux width is reduced, the incident light is incident on the subsequent diffuser plate 1104 and diffused, and the light uniformity is improved to improve the light uniformity. Then, the light enters the concave lens 1105 at the subsequent stage and is converted into a parallel light beam.

  The blue light collimated by the concave lens 1105 is incident on the mirror with spectral characteristics 1106 disposed at an inclination of about 45 degrees with respect to the optical axis, the light traveling direction is changed by 90 degrees, and the convex lens 1107 is moved to the subsequent stage. Incident. The mirror with spectral characteristics 1106 reflects the light in the blue wavelength range emitted from the laser light source 1101, and the phosphor wheel 3 converts the wavelength of the fluorescence wavelength using the blue light from the laser light source 1101 as excitation light. Has spectral characteristics that pass through.

  Here, the mirror with spectral characteristics 1106 has spectral characteristics focusing on the wavelength characteristics of the blue light from the laser light source and the wavelength-converted fluorescence, but focusing on the polarization direction of the laser light source, By adjusting the polarization direction of the blue light in the same direction, the light of the wavelength range of the blue light from the laser light source and the light in the polarization direction pass through, and have spectral characteristics that pay attention to the wavelength characteristics of the wavelength-converted fluorescence. May be.

  The blue light incident on the convex lens 1107 enters the wavelength conversion element 101 in which a part of the ring provided on the subsequent phosphor wheel 3 is missing in combination with the subsequent convex lens 1108. The phosphor wheel 3 is provided with a motor 309, and the blue excitation light condensed by the convex lenses 1107 and 1108 is arranged around the rotation axis of the ring-shaped wavelength conversion element 101 and the opening 308. It arrange | positions so that it may inject into the made radius area | region.

  The blue light collected on the wavelength conversion element 101 of the phosphor wheel 3 by the convex lenses 1107 and 1108 is converted into fluorescent light, and the traveling direction of the light is changed by 180 degrees, and the convex light is again applied to the convex lenses 1108 and 1107. Incident light is incident in this order to be collimated. The wavelength-converted fluorescence here is optimized in the wavelength region so as to form, for example, white light in combination with the blue light emitted from the laser light source 1101.

  The fluorescence emitted from the convex lens 1107 and converted into parallel light enters the mirror 1106 with spectral characteristics again. Since the mirror with spectral characteristics 1106 has the characteristic of transmitting light in the fluorescence wavelength region as described above, it passes through without changing the direction of the light.

  Next, the blue light from the laser light source 1101 collected at the opening 308 of the phosphor wheel 3 passes through the phosphor wheel 3 and is collimated by the convex lenses 1121 and 1122 at the subsequent stages. Thereafter, the light from the laser light source 1101 is transmitted to the mirror 1106 with spectral characteristics by a relay lens system including three reflecting mirrors 1123, 1125, and 1127 and three convex lenses 1124, 1126, and 1128 provided in the subsequent stage. The light is converted into parallel light from a direction opposite to the direction in which the light is incident and guided so as to be incident. Here, the relay optical system is configured by three mirrors and three convex lenses, but other configurations may be used as long as they have similar performance.

  The blue light incident on the spectroscopic mirror 1106 from the convex lens 1128 is reflected by changing the traveling direction of the light by 90 degrees.

  With the above configuration, the fluorescence and blue light synthesized by the mirror with spectral characteristics 1106 are time-divided and enter the convex lens 1109.

  The time-divided fluorescence and blue light that have entered the convex lens 1109 from the mirror 1106 with spectral characteristics are collected by the rear convex lens 1109 and incident on the rear color filter wheel 1110. The wheel 1110 with a color filter is synchronized with the phosphor wheel 3 using a synchronization circuit (not shown) and transmits blue light and a part or all of the wavelength range of the fluorescence according to the characteristics of the optical system. It is composed of a plurality of filters having characteristics.

  For example, in a time zone in which yellow fluorescence is emitted from the phosphor wheel 3, a region that transmits the fluorescence wavelength range as it is, a region that reflects red light in the fluorescence and transmits green light The wheel 1110 with a color filter having at least one region among the regions that reflect the green light and transmit the red light in the fluorescence rotates in synchronization. In addition, the blue light that has passed through the opening 308 of the phosphor wheel 3 corresponds to a region that transmits the fluorescence wavelength region as it is, so that the wavelength region of the light in chronological order near the incident end of the rod integrator 1111. Different colored lights are condensed.

  The light incident on the rod integrator 1111 is made uniform by the rod integrator, and the uniformed light is emitted from the emission end.

  In the present embodiment, the color filter-equipped wheel 1110 is disposed in front of the rod integrator 1111, but may be disposed after the rod integrator 1111.

  FIG. 15 shows a third light source device using a third phosphor wheel using a ring-shaped wavelength conversion element as the light source device 13. Hereinafter, the light source device 13 will be described using the phosphor wheel 4 using the wavelength conversion element 101 shown in FIG.

  Laser light in the blue wavelength range emitted from the plurality of laser light sources 1301 is collimated by a plurality of collimator lenses 1302 provided corresponding to each of the laser light sources 1301. The collimated blue light is incident on the convex lens 1303 at the subsequent stage, the light flux width is reduced, and the light is incident on the subsequent diffusion plate 1304 and diffused to improve the uniformity of the light. The blue light whose light uniformity is improved is incident on the concave lens 1305 at the subsequent stage to be converted into a parallel light beam.

  In the state where the concave lens 1305 is emitted, the optical system up to the concave lens 1305 is adjusted so that the polarization direction of the laser light is S-polarized with respect to the mirror 1306 with spectral characteristics at the subsequent stage. Note that the mirror 1306 with spectral characteristics has polarization characteristics and spectral characteristics.

  The blue light collimated by the concave lens 1305 is incident on a mirror 1306 having spectral characteristics arranged at an inclination of about 45 degrees with respect to the optical axis, the light traveling direction is changed by 90 degrees, and the latter stage λ / 4 wavelength plate 1307 enters. The mirror with spectral characteristics 1306 reflects the S-polarized light in the wavelength range of the blue light emitted from the laser light source 1301, and is converted in wavelength by the phosphor wheel 4 described later using the blue light from the laser light source 1301 as excitation light. It has spectral characteristics that pass light in the fluorescent wavelength range. The λ / 4 wavelength plate 1307 rotates the polarization direction of the blue light from the incident laser light source 1301 to change it into circularly polarized light.

  The light emitted from the λ / 4 wavelength plate 1307 is incident on the convex lens 1308, and is a wavelength in which a reflective film 408 is provided on the surface of a part of the ring provided on the phosphor wheel 4 in combination with the convex lens 1309 in the subsequent stage. The light enters the conversion element 101. The phosphor wheel 4 is provided with a motor 409, and blue excitation light condensed by the convex lenses 1308 and 1309 is arranged around the rotation axis of the ring-shaped wavelength conversion element 101 and the reflection film 408. It arrange | positions so that it may inject into the made radius area | region.

  First, the blue light condensed on the wavelength conversion element 101 of the phosphor wheel 4 by the convex lenses 1308 and 1309 is wavelength-converted into fluorescence, and the traveling direction of the light is changed by 180 degrees. 1308 enters in this order and is collimated. Here, the wavelength-converted fluorescence is optimized in wavelength region so as to form, for example, white light in combination with blue light emitted from the laser light source 1301.

  The fluorescence emitted from the convex lens 1308 and converted into parallel light passes through the λ / 4 wavelength plate 1307 and is incident again on the mirror 1306 with spectral characteristics arranged at an angle of 45 degrees with respect to the optical axis. As described above, the spectroscopic mirror 1306 has a characteristic of transmitting light in the fluorescence wavelength region, so that the fluorescence that has passed through the λ / 4 wavelength plate 1307 passes through without changing the direction of the light. .

  Next, the blue light from the laser light source 1301 collected on the reflection film 408 of the phosphor wheel 4 reflects the phosphor wheel 4, changes its traveling direction by 180 degrees, and enters the convex lenses 1309 and 1308 in parallel. It becomes.

  The blue light collimated by the convex lenses 1309 and 1308 enters the λ / 4 wavelength plate 1307, rotates its polarization direction, and is converted to P-polarized light.

  The P-polarized blue light emitted from the λ / 4 wavelength plate 1307 is incident on a mirror 1306 with spectral characteristics arranged at an angle of 45 degrees with respect to the optical axis. The spectroscopic mirror 1306 reflects the S-polarized light in the blue light wavelength region emitted from the laser light source 1301, and reflects the P-polarized light in the blue light wavelength region and the fluorescence converted by the phosphor wheel 4. It has the characteristic of transmitting light in the wavelength region. Therefore, the P-polarized blue light emitted from the λ / 4 wavelength plate 1307 enters the convex lens 1310.

  In accordance with the rotation of the phosphor wheel 4, fluorescence and blue light are incident on the convex lens 1310 in a time series, are condensed, and are incident on the subsequent wheel 1311 with a color filter. The wheel 1311 with a color filter is synchronized with the phosphor wheel 4 using a synchronization circuit (not shown), and has characteristics such as transmitting blue light and a part of the fluorescent light or the entire wavelength region in accordance with the characteristics of the optical system. It is comprised by the some filter which has.

  For example, in a time zone in which yellow fluorescence is emitted from the phosphor wheel 4, a region that transmits the fluorescence wavelength region as it is, a region that reflects red light in the fluorescence and transmits green light The wheel 1311 with a color filter having at least one region among the regions that reflect the green light and transmit the red light in the fluorescence rotates synchronously. Also, the blue light reflected by the reflective film 408 of the phosphor wheel 4 corresponds to the region of the wheel 1311 with a color filter that transmits the fluorescent wavelength region as it is, so that the vicinity of the incident end of the rod integrator 1312 Color lights with different wavelength ranges of light are collected in series. The light incident on the rod integrator 1312 is made uniform by the rod integrator, and the uniformed light is emitted from the emission end.

  In the present embodiment, the color filter-equipped wheel 1311 is disposed in front of the rod integrator 1312, but may be disposed after the rod integrator 1312.

[1-2-2. Effect etc.]
In the light source device 9, the wavelength conversion element 101 is used for the phosphor wheel 1. Therefore, the phosphor particle 111a having a large particle diameter provided on the side where the blue light from the laser light source 901 is incident maximizes the absorption efficiency into the phosphor, and then is positioned in the middle in the thickness direction of the phosphor region The phosphor particle 112a having a small particle size maximizes the coupling efficiency, and finally the phosphor particle 113a having the large particle size closest to the substrate in the thickness direction of the phosphor region improves thermal conductivity and reduces temperature quenching. Maximize fluorescence efficiency. This makes it possible to maximize the efficiency represented by absorption efficiency × binding efficiency × fluorescence efficiency.

  Also in the light source devices 11 and 13, since the wavelength conversion element 101 is used for each phosphor wheel 3 and 4, the efficiency can be maximized as in the light source device 9.

  The light source which is the first to third light source devices using the wavelength conversion element 101 even when the first to third light source devices are configured using the first to third phosphor wheels using the wavelength conversion device 102. Similar to the devices 9, 11, and 13, the efficiency represented by absorption efficiency × binding efficiency × fluorescence efficiency can be maximized.

[1-3-1. Projection-type image display device including light source device]
A configuration of the projection display apparatus 10 using the first light source device using the first phosphor wheel using the ring-shaped wavelength conversion element 101 will be described.

  First, FIG. 12 shows a configuration of a projection display apparatus 10 using a light source device 9 as a first light source device.

  Since the light source device 9 using the phosphor wheel 1 using the ring-shaped wavelength conversion element 101 has been described above, the description thereof will be omitted.

  The light emitted from the rod integrator 910 is mapped to DMDs (digital micromirror devices) 1041, 1042, and 1043 by a relay lens system including convex lenses 1031, 1032, and 1033.

  The light emitted from the relay lens system including the convex lenses 1031, 1032, 1033 is incident on the total reflection prism 1034 provided with the minute gap 1035. Light emitted from the relay lens system and incident on the total reflection prism 1034 at an angle greater than or equal to the total reflection angle is reflected by the minute gap 1035 and changed in the traveling direction of the light, and is composed of three glass blocks provided with the minute gap 1037. Is incident on the color prism 1036.

  Of the blue light and fluorescent light incident on the first glass block of the color prism 1036 from the total reflection prism 1034, the blue light is first provided with a spectral characteristic reflecting film having a blue reflection characteristic provided in the front stage of the small gap 1037. , The direction of travel is changed, the light travels toward the total reflection prism, enters the small gap provided between the total reflection prism 1034 and the color prism 1036 at an angle greater than the total reflection angle, and displays a blue image. It enters the DMD 1043 to be displayed.

  Subsequently, of the fluorescent light that has passed through the minute gap, the red light reflects the light in the red wavelength region provided between the second and third glass blocks of the color prism 1036 and passes the green light. Is reflected by the reflective film with spectral characteristics having the spectral characteristics to change the traveling direction to the first glass block side.

  The red light whose direction of travel has been changed is reflected again by the minute gap 1037 provided between the first and second glass blocks of the color prism 1036 and is incident on the red DMD 1042 by changing the direction of travel of the light. To do.

  Further, among the fluorescent light that has passed through the minute gap, the green light reflects the light in the red wavelength region provided between the second and third glass blocks of the color prism, and spectral characteristics that pass the green light. It passes through the reflective film with spectral characteristics having the above, proceeds to the third glass block as it is, and enters the green DMD 1041 as it is.

  DMDs 1041, 1042, and 1043 change the traveling direction of light by changing the direction of the mirror for each pixel in accordance with the video signal of each color from a video circuit (not shown).

  First, green light whose light traveling direction has been changed by the DMD 1041 for green according to the video signal is incident on the third glass block of the color prism 1036 and between the third and second glass blocks of the color prism 1036. It passes through the reflective film with spectral characteristics provided in the.

  Subsequently, the red light whose light traveling direction has been changed by the DMD 1042 for red according to the video signal is incident on the second glass block of the color prism 1036, and the second and first glass blocks of the color prism 1036. The light is reflected by being incident on a minute gap 1037 provided therebetween at an angle greater than the total reflection angle. Thereafter, the red light is reflected by the reflective film with spectral characteristics provided between the second and third glass blocks of the color prism 1036 by changing the traveling direction of the light to the third glass block of the color prism. The traveling direction of the light is changed and synthesized with green light.

  The light synthesized by the reflective film with spectral characteristics travels to the first glass block side of the color prism 1036 and is totally reflected by the minute gap 1037 provided between the second and first glass blocks of the color prism 1036. It is transmitted by entering at an angle less than the angle.

  Further, the blue light whose light traveling direction has been changed by the blue DMD 1043 according to the video signal is incident on the first glass block of the color prism 1036 and travels toward the total reflection prism 1034 side. By entering the gap provided between the color prism 1036 at an angle equal to or greater than the total reflection angle, the color prism 1036 advances toward the second glass block. Thereafter, the blue light is reflected by a mirror with spectral characteristics provided on the first glass block side in front of the minute gap 1037 provided between the first and second glass blocks of the color prism 1036, and is totally reflected. The traveling direction of the light is changed to the prism 1034 side, and the light from the green DMD 1041 and the red DMD 1042 is combined and enters the total reflection prism 1034.

  The light from the DMDs 1041, 1042, and 1043 incident on the total reflection prism 1034 is transmitted by entering the minute gap 1035 of the total reflection prism 1034 at an angle equal to or smaller than the total reflection angle, and is incident on the projection lens 1051, which is not illustrated. The screen is irradiated.

  Next, FIG. 14 shows a configuration of a projection display apparatus 12 using a light source device 11 as a second light source device.

  Since the light source device 11 using the phosphor wheel 2 using the segment-shaped wavelength conversion element 101 has been described above, the description thereof will be omitted.

  The light emitted from the rod integrator 1111 is mapped to a DMD 1241 described later by a relay lens system including convex lenses 1231, 1232, and 1233.

  The light that has passed through the convex lenses 1231, 1232, and 1233 and entered the total reflection prism 1234 enters the minute gap 1235 of the total reflection prism 1234 at an angle that is greater than the total reflection angle, and is reflected to change the traveling direction of the light. The light enters the DMD 1241.

  The DMD 1241 emits light by changing the direction of the minute mirror and changing the traveling direction of the light according to a signal from a video circuit (not shown) synchronized with the color light emitted by the combination of the phosphor wheel 3 and the wheel 1110 with a color filter. .

  The light whose traveling direction has changed in accordance with the video signal in the DMD 1241 is incident on the total reflection prism 1234, and is incident on the minute gap 1235 of the total reflection prism 1234 at an angle equal to or smaller than the total reflection angle. Then, the light enters the projection lens 1251 and is projected on a screen (not shown).

  Finally, FIG. 16 shows a configuration of a projection display apparatus 14 using a light source device 13 as a third light source device.

  Since the light source device 13 using the phosphor wheel 3 using the ring-shaped wavelength conversion element 101 and having the reflective film 408 provided on the surface thereof has been described above, the description thereof is omitted.

  The light emitted from the rod integrator 1312 is mapped to a DMD 1441 described later by a relay lens system including convex lenses 1431, 1432 and 1433.

  The light that has passed through the convex lenses 1431, 1432, and 1433 and entered the total reflection prism 1434 enters the microgap 1435 of the total reflection prism 1434 at an angle greater than the total reflection angle, and is reflected to change the traveling direction of the light. Incident on DMD 1441.

  The DMD 1441 changes the direction of the minute mirror and changes the traveling direction of the light in accordance with a signal from a video circuit (not shown) synchronized with the color light emitted by the combination of the phosphor wheel 4 and the color filter wheel 1311. .

  The light whose traveling direction has changed in accordance with the video signal in the DMD 1441 is incident on the total reflection prism 1434 and is transmitted as it is by being incident on the minute gap 1435 of the total reflection prism 1434 at an angle equal to or smaller than the total reflection angle. Then, the light enters the projection lens 1451 and is projected on a screen (not shown).

[1-3-2. Effect etc.]
In the projection display apparatus 10 using the light source device 9, the wavelength conversion element 101 is used for the phosphor wheel 1. Therefore, the absorption efficiency is maximized by the large particle size phosphor particles 111a provided on the side where the blue light from the laser light source 901 is incident, and then the small particle size particle positioned in the middle in the thickness direction of the phosphor region. The phosphor particle 112a maximizes the coupling efficiency, and finally the phosphor particle 113a having a large particle diameter closest to the substrate in the thickness direction of the phosphor region improves thermal conductivity, reduces temperature quenching, and maximizes the fluorescence efficiency. Turn into. This makes it possible to maximize the efficiency represented by absorption efficiency × binding efficiency × fluorescence efficiency.

  Even in the projection display apparatuses 12 and 14 using the light source apparatuses 11 and 13, the wavelength conversion elements 101 are used for the phosphor wheels 2 and 3, respectively, so that the efficiency is maximized as in the projection display apparatus 10. be able to.

(Embodiment 2)
[2-1-1-1. Configuration of wavelength conversion element]
Hereinafter, the configuration of the wavelength conversion element according to the second embodiment will be described in detail. FIG. 8 is a configuration diagram of the wavelength conversion element in the second embodiment. FIG. 8A is a cross-sectional view of the first wavelength conversion element in the second embodiment, and FIG. 8B is the embodiment. Sectional drawing of 2nd 2nd wavelength conversion element of FIG. 8, (c) of FIG. 8 shows the top view of a wavelength conversion element.

  As shown in FIG. 8A, the wavelength conversion element 601 that is the first wavelength conversion element of the second embodiment is a first phosphor region 611 composed of phosphor particles 611a and a first phosphor region 611a composed of phosphor particles 612a. The phosphor region is composed of two layers in which two phosphor regions 612 are laminated. As shown in FIG. 8, phosphor particles having different particle diameters are arranged in the thickness direction of the phosphor region, but here, the particles of phosphor particles 611a on the surface side (upper side of FIG. 8 (a)) The diameter is larger than the particle diameter of the phosphor particles 612a on the back surface side (the lower side in FIG. 8A).

  As shown in FIG. 8B, the wavelength conversion element 602, which is the second wavelength conversion element of the second embodiment, fills phosphor particles 621a and 622a having different particle diameters with a binder 624 such as silicone. Thus, the first phosphor region 621 and the second phosphor region 622 are configured. As shown in FIG. 8, phosphor particles having different particle diameters are arranged in the thickness direction of the phosphor region, similarly to the wavelength conversion element 601, but here the surface side (upper side of FIG. 8B) The particle size of the phosphor particles 621a is larger than the particle size of the phosphor particles 622a on the back surface side (the lower side of FIG. 8B).

  FIG. 8C is a plan view when a phosphor ring is formed using the wavelength conversion elements 601 and 602. Here, the ring shape is used for the following description, but it may be a segment shape in which a part of the ring is missing, or may be a polygonal shape such as a quadrangle.

[2-1-1-2. Configuration of phosphor wheel using wavelength conversion element]
Hereinafter, the configuration of the phosphor wheel will be described using the phosphor ring formed by the wavelength conversion elements 601 and 602 shown in FIG.

  FIG. 9 shows first and second phosphor wheels using the wavelength conversion elements 601 and 602 of the second embodiment. 9A is a plan view of the first and second phosphor wheels using the wavelength conversion elements 601 and 602, and FIG. 9B is a plan view of the first phosphor wheel using the wavelength conversion element 601. FIG. 9C is a cross-sectional view of a second phosphor wheel using the wavelength conversion element 602.

  In the phosphor wheel 7 as the first phosphor wheel using the wavelength conversion element 601 shown in FIG. 9, the first phosphor region 611 side composed of the phosphor particles 611a having the larger particle diameter has the excitation light L side. Arranged on the incident side. Similarly, in the phosphor wheel 7 as the second phosphor wheel using the wavelength conversion element 602, the first phosphor region 621 side composed of phosphor particles 621a having a larger particle diameter is on the incident side of the excitation light L. Placed in.

  First, the phosphor wheel 7 using the wavelength conversion element 601 will be described with reference to FIGS. As shown in FIG. 9B, the phosphor wheel 7 includes a phosphor ring using the wavelength conversion element 601 provided with an antireflection film 703 on the surface, and a substrate 705 provided with a reflection layer 706 on the surface. A silicone layer 704 filled with contained particles 741 that improve thermal conductivity and reflectance is provided between the reflective layer 706 and the phosphor ring. A motor mounting hole 707 is provided in the substrate 705.

  The wavelength conversion element 601 configured as a phosphor ring is composed of phosphor particles 611a and 612a having different particle diameters, and the particle diameters of the phosphor particles are different in the thickness direction of the phosphor region. Here, the phosphor particles 611a on the front side have a larger particle size than the phosphor particles 612a on the substrate 705 side.

  Next, the configuration of the phosphor wheel 7 using the wavelength conversion element 602 will be described with reference to FIGS.

  As shown in FIG. 9C, the phosphor wheel 7 includes a phosphor ring using a wavelength conversion element 602 having an antireflection film 703 provided on the surface, and a substrate 705 having a reflection layer 706 provided on the surface. A silicone layer 704 filled with contained particles 741 that improve thermal conductivity and reflectance is provided between the reflective layer 706 and the phosphor ring.

  The wavelength conversion element 602 configured as a phosphor ring is composed of phosphor particles 621a and 622a having different particle diameters and a binder 624 made of, for example, silicone, and the phosphor particles are arranged in the thickness direction of the phosphor region. The particle size is different. Here, the phosphor particles 621a on the surface side have a larger particle size than the phosphor particles 622a on the substrate 705 side.

  FIG. 10 shows third and fourth phosphor wheels using the wavelength conversion elements 601 and 602 of the second embodiment. 10A is a plan view of the third and fourth phosphor wheels using the wavelength conversion elements 601 and 602, and FIG. 10B is a plan view of the third phosphor wheel using the wavelength conversion element 601. FIG. 10C is a cross-sectional view of a fourth phosphor wheel using the wavelength conversion element 602.

  The phosphor wheel 8 as the third phosphor wheel using the wavelength conversion element 601 shown in FIG. 10 has the second phosphor region 612 side composed of the phosphor particles 612a having the smaller particle diameters of the excitation light L. Arranged on the incident side. Similarly, in the phosphor wheel 8 as the fourth phosphor wheel using the wavelength conversion element 602, the second phosphor region 622 composed of phosphor particles 622a having a smaller particle diameter is provided on the incident side of the excitation light L. Placed in.

  First, the structure of the phosphor wheel 8 using the wavelength conversion element 601 will be described with reference to FIGS. As shown in FIG. 10B, the phosphor wheel 8 includes a phosphor ring using a wavelength conversion element 601 having an antireflection film 803 provided on the surface, and a substrate 805 having a reflection layer 806 provided on the surface. And a silicone layer 804 filled with contained particles 841 that improve thermal conductivity and reflectivity is provided between the reflective layer 806 and the phosphor ring. A motor mounting hole 807 is provided in the substrate 805.

  The wavelength conversion element 601 configured as a phosphor ring is composed of phosphor particles 611a and 612a having different particle diameters, and the particle diameters of the phosphor particles are different in the thickness direction of the phosphor region. Here, the phosphor particles 612a on the front side have a smaller particle size than the phosphor particles 611a on the substrate 805 side.

  Next, the configuration of the phosphor wheel 8 using the wavelength conversion element 602 will be described with reference to FIGS.

  As shown in FIG. 10C, the phosphor wheel 8 includes a phosphor ring using a wavelength conversion element 602 having an antireflection film 803 provided on the surface, and a substrate 805 having a reflection layer 806 provided on the surface. And a silicone layer 804 filled with contained particles 841 that improve thermal conductivity and reflectivity is provided between the reflective layer 806 and the phosphor ring.

  The wavelength conversion element 602 configured as a phosphor ring is composed of phosphor particles 621a and 622a having different particle diameters and a binder 624 made of, for example, silicone, and the phosphor particles are arranged in the thickness direction of the phosphor region. The particle size is different. Here, the phosphor particles 622a on the surface side have a smaller particle size than the phosphor particles 621a on the substrate 805 side.

[2-1-2. Effect etc.]
Like the phosphor wheel 7 using the wavelength conversion elements 601 and 602, two types of phosphor particles having different particle sizes are arranged in the thickness direction of the phosphor region, and phosphor particles having a large particle size are arranged on the substrate side. By arranging phosphor particles with a small particle size, this improves the coupling efficiency with respect to a phosphor wheel composed only of phosphor particles with a large particle size, and fluorescence composed only with phosphor particles with a small particle size. Absorption efficiency is improved relative to the body wheel, improving efficiency.

  Further, when phosphor particles having a small particle diameter are arranged on the surface side and phosphor particles having a large particle diameter are arranged on the substrate side as in the phosphor wheel 8 using the wavelength conversion elements 601 and 602, The coupling efficiency is improved for a phosphor wheel composed only of large phosphor particles, and the heat conduction characteristics are improved for the phosphor wheel composed only of phosphor particles having a small particle size to improve the fluorescence efficiency. .

  In addition, the phosphor wheel of the first embodiment is composed of three types of phosphor particles having different particle sizes, whereas the phosphor wheel of the second embodiment is composed of two types of phosphor particles having different particle sizes. By being configured, there is also an advantage that the manufacture becomes easy.

[2-2-1. Configuration of light source device including phosphor wheel]
By replacing the wavelength conversion element of the second embodiment with the wavelength conversion elements used in the first to third phosphor wheels of the first embodiment, the first to first shown in FIGS. 3 light source devices can be configured. Since the behavior of the light source device in this case is the same as that of the light source device of the first embodiment, description thereof is omitted.

[2-2-2. Effect etc.]
As described in the item of the effect of the phosphor wheel using the wavelength conversion element of the second embodiment, by arranging two kinds of phosphor particles having different particle diameters in the thickness direction of the phosphor region, the particle diameter is increased. The coupling efficiency is improved with respect to a light source device using a phosphor wheel composed only of phosphor particles. Also, in contrast to a light source device using a phosphor wheel composed only of phosphor particles having a small particle diameter, a large phosphor particle arranged on the surface side has improved absorption efficiency, and a small phosphor particle is arranged on the surface side. In the case of the arrangement, the thermal conductivity is improved and the fluorescence efficiency is improved.

[2-3-1. Configuration of projection-type image display device including light source device]
By replacing the wavelength conversion element of the second embodiment with the wavelength conversion elements used in the first to third phosphor wheels of the first embodiment, the first to third of FIGS. 12, 14, and 16 are used. A projection display apparatus using the light source device can be configured.

[2-3-2. Effect etc.]
As described above in the item of the effect of the phosphor wheel using the wavelength conversion element of the second embodiment, by arranging two types of phosphor particles having different particle diameters in the thickness direction of the phosphor region, the particle diameter is increased. The coupling efficiency is improved with respect to the projection display apparatus using the light source device using the phosphor wheel composed only of the phosphor particles. Further, the absorption efficiency is improved and the efficiency is improved with respect to the projection display apparatus using the light source device using the phosphor wheel composed only of phosphor particles having a small particle diameter.

(Embodiment 3)
[3-1. Configuration of wavelength conversion element]
Hereinafter, the structure of the wavelength conversion element in Embodiment 3 is demonstrated. 17A and 17B are diagrams showing the configuration of the wavelength conversion element in the third embodiment. FIG. 17A is a cross-sectional view of the wavelength conversion element 301, and FIG. 17B is a cross-sectional view of the wavelength conversion element 302. FIG. 17C shows a plan view of a phosphor ring formed by using the wavelength conversion elements 301 and 302.

  A wavelength conversion element 301 shown in FIG. 17A includes a first phosphor region 311 composed of phosphor particles 311a, a second phosphor region 312 composed of phosphor particles 312a, and a third phosphor composed of phosphor particles 313a. The region 313 is composed of three layers of phosphor regions. As shown in FIG. 17A, phosphor particles having different particle diameters are arranged in the thickness direction of the phosphor region. Here, the fluorescence constituting the second phosphor region 312 arranged in the middle is arranged. The particle size of the body particles 312a is such that the phosphor particles 311a in the first phosphor region 311 on the front surface side (upper side of FIG. 17A) and the third fluorescence on the back surface side (lower side of FIG. 17B). It is larger than the particle size of the phosphor particles 313a in the body region 313.

  Here, the phosphor particles 311a in the first phosphor region 311 and the phosphor particles 313a in the third phosphor region 313 may be different or the same.

  A wavelength conversion element 302 shown in FIG. 17B includes a first phosphor region 321 composed of phosphor particles 321a, a second phosphor region 322 composed of phosphor particles 322a, and a third phosphor composed of phosphor particles 323a. The region 323 is composed of three layers of phosphor regions that are stacked with a binder 324 such as silicone interposed therebetween. As shown in FIG. 17B, phosphor particles having different particle diameters are arranged in the thickness direction of the phosphor region. Here, the fluorescence constituting the second phosphor region 322 arranged in the middle is arranged. The particle size of the body particles 322a is such that the phosphor particles 321a of the first phosphor region 321 on the front surface side (upper side of FIG. 17B) and the third fluorescence on the back surface side (lower side of FIG. 17B). The particle size of the phosphor particles 323a in the body region 323 is larger.

  Here, the phosphor particles 321a in the first phosphor region 321 and the phosphor particles 323a in the third phosphor region 323 may be different or the same.

  As described above, the wavelength conversion elements 301 and 302 are arranged in the middle in that the particle size of the phosphor particles in the second phosphor region arranged in the middle is larger than the particle size of the phosphor particles in other regions. The particle size of the phosphor particles in the second phosphor region is different from that of the wavelength conversion elements 101 and 102 of the first embodiment, which is smaller than the particle size of the phosphor particles in other regions.

  As shown in FIG. 17C, the wavelength conversion elements 301 and 302 have a ring shape, but the phosphor ring may have a segment shape in which a part of the ring is missing, or a polygon such as a rectangle. It may be in shape.

[3-2. Phosphor wheel using wavelength conversion element, light source device and projection display device]
By replacing the wavelength conversion elements 301 and 302 with the wavelength conversion element 101 of the first embodiment, the first to third phosphor wheels using the wavelength conversion elements 301 and 302 are configured as in the first embodiment. Can do.

  The first to third phosphors using wavelength conversion elements 301 and 302 as the first to third phosphor wheels used in the first to third light source devices of the projection display apparatus described in the first embodiment. A wheel can be used.

[3-3. Effect etc.]
As described above, the wavelength conversion elements 301 and 302 according to the third embodiment have phosphor particles with small particle diameters arranged on the L incident side of the excitation light. Tend to improve the coupling efficiency. Therefore, it is suitable when the optical system at the rear stage of the projection display apparatus is downsized.

  The present disclosure can be applied to a light source device of a projection display apparatus.

1, 2, 3, 4, 5, 7, 8 Phosphor wheel 9, 11, 13 Light source device 10, 12, 14 Projection display device 101, 102, 201, 202, 301, 302, 601, 602 Wavelength conversion Element 103, 203, 303, 403, 503, 703, 803 Antireflection film 104, 204, 304, 404, 504, 704, 804 Silicone layer 105, 205, 305, 405, 505, 705, 805 Substrate 106, 206, 306, 406, 506, 706, 806 Reflective layer 107, 207, 307, 407, 507, 707, 807 Motor mounting hole 109, 309, 409 Motor 111, 121, 311, 321, 611, 621 First phosphor region 112 , 122, 312, 322, 612, 622 Second phosphor region 113, 123, 13, 323 Third phosphor region 111a, 112a, 113a, 121a, 122a, 123a, 211a, 221a, 311a, 312a, 313a, 321a, 322a, 323a, 611a, 612a, 621a, 622a Phosphor particles 124, 324, 624 Binder 141, 341, 441, 541, 741, 841 Containing particles 211, 221 Phosphor region 308 Opening 408 Reflecting film 901, 921, 1101, 1301 Laser light source 902, 922, 1102, 1302 Collimator lens 903, 907, 908 909, 923, 1103, 1107, 1108, 1109, 1121, 1122, 1124, 1126, 1128, 1303, 1308, 1309, 1310, 1031, 1032, 1033, 1231, 232, 1233, 1431, 1432, 1433 Convex lenses 904, 924, 1104, 1304 Diffuser plates 905, 925, 1105, 1305 Concave lenses 906, 1106, 1306 Mirrors with spectral characteristics 910, 1111, 1312 Rod integrators 1041, 1042, 1043, 1241 1441 DMD
1034, 1234, 1434 Total reflection prism 1035, 1037, 1235, 1435 Micro gap 1036 Color prism 1110, 1311 Wheel with color filter 1123, 1125, 1127 Reflection mirror 1051, 1251, 1451 Projection lens 1307 λ / 4 wavelength plate

Claims (14)

A first phosphor region;
A second phosphor region that is disposed in the thickness direction of the first phosphor region and in which phosphor particles having a particle size different from that of the phosphor particles located in the first phosphor region are located
A wavelength conversion element comprising: A third phosphor region disposed in the thickness direction of the first phosphor region so that the second phosphor region is disposed in the middle;
The particle size of the phosphor particles located in the second phosphor region is smaller than the particle size of the phosphor particles located in the first phosphor region and the third phosphor region,
The wavelength conversion element according to claim 1. A third phosphor region disposed in the thickness direction of the first phosphor region so that the second phosphor region is disposed in the middle;
The particle size of the phosphor particles located in the second phosphor region is larger than the particle size of the phosphor particles located in the first phosphor region and the third phosphor region,
The wavelength conversion element according to claim 1. The first phosphor region and the third phosphor region have phosphor particles having substantially the same particle size,
The wavelength conversion element according to claim 2 or 3. The particle size of the phosphor particles located in the first phosphor region is larger than the particle size of the phosphor particles located in the second phosphor region,
The wavelength conversion element according to claim 1. The first phosphor region is located on an excitation light incident side;
The wavelength conversion element according to claim 5. The second phosphor region is located on the incident side of the excitation light;
The wavelength conversion element according to claim 5. The wavelength conversion element according to any one of claims 1 to 7,
A substrate on which the wavelength conversion element is provided;
A motor for rotationally driving the substrate;
Phosphor wheel with The wavelength conversion element has a ring shape,
The phosphor wheel according to claim 8. The wavelength conversion element is a segment shape having a missing part in which a part of the ring shape is missing,
The phosphor wheel according to claim 8. The substrate has an opening corresponding to the missing portion;
The wavelength conversion element and the opening are disposed at substantially the same distance from the rotation center of the phosphor wheel,
The phosphor wheel according to claim 10. The wavelength conversion element has a ring shape,
A reflective layer is provided on a part of the surface of the wavelength conversion element,
The phosphor wheel according to claim 8.   A light source device comprising the phosphor wheel according to claim 8.   A projection display apparatus comprising the light source device according to claim 13.

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