JP2012074242A - Light-emitting device and projector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light-emitting device and a projector which reflect light from a light source using a concave mirror, in which efficient condensing of light is attained.SOLUTION: The light-emitting device 100 is provided with a concave mirror 110 which has an opening to a Z-direction, an excitation light source 140 which irradiates excitation light LT toward a focal point CP1 of the concave mirror 110, and a rotating part 120 which rotates using an axis 131 along an X-direction as a rotating axis. The rotating part 120 rotates so that a part of the rotating part 120 may pass the focal point CP1 of the concave mirror 110 through a slit SL of the concave mirror 110. A light-emitting part 122 is provided at least at a part of the rotating part 120 so that light may be emitted from a face on the front side or a face on the rear side of the rotating part 120 by the excitation light LT reaching the focal point CP1. The concave mirror 110 is arranged at a position where light from the front side face and the rear side face of the rotating part 120 is reflected.

Description

  The present invention relates to a light emitting device and a projector that reflect light from a light source using a concave mirror.

  In recent years, projectors are often used in presentations such as conferences. In recent years, projectors using a DMD (Digital Micro mirror Device), a liquid crystal panel, or the like are the mainstream.

  In order to extend the life of the light source, it is expected that projectors using a laser light source or an LED (Light Emitting Diode) light source will become the mainstream instead of the conventional high-pressure mercury lamp. A laser light source is a light source using a laser emitted from a light emitting element. An LED light source is a light source using light emitted from an LED as a light emitting element. Hereinafter, the laser light source or the LED light source is referred to as a light emitting element light source.

  In Patent Documents 1 and 2, a technique (hereinafter referred to as Conventional Technology A) for suppressing a temperature rise of the phosphor by rotating the phosphor (phosphor layer) using a light emitting element light source as a light source is disclosed. It is disclosed.

JP 2010-086815 A US Pat. No. 7,547,114

  However, the prior art A has a problem in that the light collection efficiency is very poor because only the light directed from the phosphor layer in the direction in which the lens is provided is used.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a light-emitting device and the like that can realize efficient light collection.

  In order to solve the above-described problem, a light-emitting device according to one embodiment of the present invention includes a concave mirror that opens in a first direction, and excitation light toward an internal point that is a part of a space inside the concave mirror. An excitation light source to be irradiated; and a rotation unit that rotates about an axis along a second direction orthogonal to the first direction as a rotation axis, and the rotation unit emits light by the excitation light from the excitation light source The concave mirror includes a light emitting unit, and the concave mirror is provided with a slit, and the rotating unit rotates so that at least a part of the rotating unit passes through the slit and the internal point of the concave mirror, At least a part of the rotating part is provided with the light emitting part so as to emit light from the front surface and the back surface of the rotating part by the excitation light reaching the internal point from the excitation light source, The concave mirror is the front side of the rotating part. It is positioned to reflect light from the surface and back surface.

  That is, the light emitting device includes a concave mirror that is open with respect to the first direction, an excitation light source that irradiates excitation light toward an internal point of the concave mirror, and a rotating unit that rotates about an axis along the second direction as a rotation axis. Prepare. The rotating part rotates so that at least a part of the rotating part passes through the internal point of the concave mirror through the slit of the concave mirror. At least a part of the rotating part is provided with the light emitting part so as to emit light from the surface on the front side and the surface on the back side of the rotating part by the excitation light reaching the internal point. A concave mirror is arrange | positioned in the position which reflects the light from the surface of the front side of the said rotation part, and the surface of a back side.

  Therefore, the concave mirror reflects light from both the front surface and the back surface of the rotating part. Therefore, the light emitting device can realize efficient light collection.

  Preferably, the slit is provided at the bottom of the concave mirror.

  Preferably, the shaft is disposed outside the concave mirror.

  Preferably, the rotating part includes a support part and the light emitting part, and the shape of the support part is circular, and the light emitting part is formed on a peripheral part of the support part.

  Preferably, the rotating part includes a support part and the light emitting part, and the shape of the support part is circular, and the light emitting part is formed on an outer peripheral part of the support part.

  Preferably, the support portion is made of a transparent material.

  Preferably, the light emitting unit is formed in the entire rotating unit.

  Preferably, the light emitting unit emits red light, green light, or blue light by the excitation light.

  Preferably, the light emitting unit is formed of a first region, a second region, and a third region, and the first region, the second region, and the third region are respectively red light by the excitation light. , Emit green light and blue light respectively.

  Preferably, the light emitting unit emits white light by the excitation light.

  Preferably, the excitation light source irradiates the internal point with the excitation light so that the excitation light is orthogonal to at least a part of the rotating part that passes through the internal point of the concave mirror.

  Thereby, it is possible to maximize the amount of light emitted by the light emitting unit provided at least in part of the rotating unit that passes through the internal point of the concave mirror.

  Preferably, the concave mirror has a parabolic shape having a focal point inside the concave mirror, and the internal point is the focal point or a point in the vicinity of the focal point.

  Preferably, the shape of the concave mirror is an ellipsoid having at least one focal point inside the concave mirror, and the internal point is the focal point or a point in the vicinity of the focal point.

  Preferably, the excitation light is laser light.

  A projector according to an aspect of the present invention includes the light emitting device.

  According to the present invention, efficient light collection can be realized.

It is sectional drawing which shows the structure of the light-emitting device which concerns on 1st Embodiment. It is a top view of the concave mirror which concerns on 1st Embodiment. It is sectional drawing of the light-emitting device which concerns on 1st Embodiment. It is a figure which shows an example of a structure of the rotation part which concerns on 1st Embodiment. It is an enlarged view of the peripheral part of a focus. It is sectional drawing which shows the structure of the light-emitting device which concerns on the modification 1 of 1st Embodiment. It is sectional drawing which shows the structure of the light-emitting device which concerns on the modification 1 of 1st Embodiment. It is a figure which shows the spectral reflection characteristic of a concave mirror. It is a figure which shows the structure of the rotation part as an example. It is a figure which shows the structure of the rotation part as an example. It is an enlarged view of the edge part of a rotation part. It is a figure which shows the structure of the rotation part as an example. It is a figure which shows schematic structure of the projector which concerns on 2nd Embodiment. It is a figure which shows schematic structure of the projector which concerns on the modification of 2nd Embodiment. It is a figure which shows the structure of the optical part as an example. It is a figure which shows the structure of the optical part as an example. It is a figure which shows the structure of the optical part as an example.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same components are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof may be omitted.

  It should be noted that the dimensions, materials, shapes, relative arrangements, and the like of the constituent elements exemplified in the embodiments are appropriately changed depending on the configuration of the apparatus to which the present invention is applied and various conditions. It is not limited to those examples. Moreover, the dimension of each component in each figure may differ from an actual dimension.

<First Embodiment>
FIG. 1 is a cross-sectional view showing a configuration of a light emitting device 100 according to the first embodiment. The light emitting device 100 is a device that emits light. In FIG. 1, the X, Y, and Z directions are orthogonal to each other. The X, Y, and Z directions shown in the following figures are also orthogonal to each other.

  Hereinafter, the three lines along the X, Y, and Z directions are also referred to as an X direction line, a Y direction line, and a Z direction line. For example, the Z direction line is a line along the Z direction.

  1 shows a motor 130 that is not included in the components of the light emitting device 100 for the sake of explanation. The motor 130 is provided with a shaft 131 extending in the X direction. The motor 130 rotates the shaft 131.

  Referring to FIG. 1, light emitting device 100 includes a concave mirror 110 and a rotating unit 120.

  A mirror is formed on the inner surface of the concave mirror 110. The concave mirror 110 has a focal point CP1 inside the concave mirror 110. The focal point CP1 is a point in the area inside the concave mirror 110. That is, the focal point CP1 is an internal point that is a part of the space inside the concave mirror 110. For example, the focal point CP1 exists at a position where the distance d1 from the bottom surface of the concave mirror 110 to the focal point CP1 is, for example, 10 mm. That is, the concave mirror 110 has a parabolic shape having a focal point CP1 inside the concave mirror 110.

  The concave mirror 110 opens with respect to the first direction as the Z direction.

  FIG. 2 is a top view of the concave mirror 110 according to the first embodiment. The diameter of the concave mirror 110 is 65 mm, for example.

  FIG. 3 is a cross-sectional view of the light emitting device 100 according to the first embodiment. Specifically, FIG. 3 is a cross-sectional view of the light emitting device 100 in the ZY plane.

  Each component will be described with reference to FIGS. 1, 2, and 3. A slit SL is provided at the bottom of the concave mirror 110.

  The rotating unit 120 is arranged such that a part of the rotating unit 120 is arranged inside the concave mirror 110 via the slit SL.

  The rotating unit 120 includes a support unit 121 and a fluorescent unit 122.

  FIG. 4 is a diagram illustrating an example of the configuration of the rotating unit 120 according to the first embodiment.

  FIG. 4A is a plan view of the rotating unit 120.

  FIG. 4B is a cross-sectional view of the rotating unit 120.

  With reference to FIG. 4A and FIG. 4B, the shape of the rotating unit 120 is a planar shape (plate shape). Moreover, the shape of the rotation part 120 is circular. Moreover, the shape of the support part 121 is circular. The diameter of the support part 121 is 34 mm as an example. The diameter of the rotating part 120 is the same as the diameter of the support part 121. The support part 121 is made of a transparent material. The transparent material is, for example, glass, silicon, resin, or the like.

  A fluorescent part 122 is formed on the peripheral part of the support part 121. That is, the fluorescent part 122 as a light emitting part is formed at the peripheral part of the rotating part 120 (support part 121). The width of the fluorescent part 122 in FIG. 4A is 4 mm, for example. The diameter of the circle on the outer periphery of the fluorescent part 122 is 34 mm as an example.

  The fluorescent part 122 is made of a phosphor. The phosphor is, for example, a red phosphor, a green phosphor, a blue phosphor, or the like.

  The red phosphor is a phosphor that emits red light when the red phosphor is irradiated with excitation light. Excitation light is light for exciting the phosphor. The red phosphor is, for example, Eu-activated alkaline earth metal nitride silicate. The peak wavelength of red light emitted from the red phosphor is 600-650 nm. When the fluorescent part 122 is made of a red phosphor, the light emitting part (fluorescent part 122) emits red light by excitation light.

  The green phosphor is a phosphor that emits green light when the green phosphor is irradiated with excitation light. The green phosphor is, for example, Eu-activated alkaline earth metal silicate. The peak wavelength of green light emitted by the green phosphor is 500-550 nm. When the fluorescent part 122 is made of a green phosphor, the light emitting part (fluorescent part 122) emits green light by excitation light.

  The blue phosphor is a phosphor that emits blue light when the blue phosphor is irradiated with excitation light. The blue phosphor is, for example, Eu-activated strontium nitride silicon. The peak wavelength of blue light emitted from the blue phosphor is 440 to 470 nm. When the fluorescent part 122 is made of a blue phosphor, the light emitting part (fluorescent part 122) emits blue light by excitation light.

  A hole H <b> 10 is formed in the center portion of the support portion 121. A part of the shaft 131 of the motor 130 passes through the hole H10, and the shaft 131 and the support portion 121 are fixed. The shaft 131 extends along the X direction. Thereby, the rotating part 120 rotates by rotating the shaft 131.

  That is, the rotating unit 120 rotates about the axis 131 along the second direction (X direction) orthogonal to the first direction (Z direction) as the rotation axis. A shaft 131 as a rotation shaft is disposed outside the concave mirror 110.

  Thereby, the rotating unit 120 rotates so that at least a part of the rotating unit 120 (for example, the fluorescent unit 122) passes through the internal point (focal point CP1) of the concave mirror 110 via the slit SL.

  The rotating unit 120 may be arranged so that the shaft 131 is arranged inside the concave mirror 110.

  Next, the focal portion will be described in detail.

  FIG. 5 is an enlarged view of a peripheral portion of the focal point CP1.

  Referring to FIG. 5, rotation unit 120 has a Z-direction line that passes through focal point CP <b> 1 and a Z-direction line that passes through the center in the X direction of the portion of rotation unit 120 where fluorescent portion 122 is formed. Placed. That is, the rotation unit 120 is disposed such that a Z-direction line passing through the center in the X direction of the portion of the rotation unit 120 where the fluorescent unit 122 is formed passes through the focal point CP1.

  The arrangement of the rotation unit 120 is not limited to the above arrangement as long as the Z-direction line passing through the focal point CP1 passes through the vicinity of the portion of the rotation unit 120 where the fluorescent part 122 is formed. That is, the Z-direction line passing through the focal point CP1 and the Z-direction line passing through the center in the X direction of the portion of the rotating unit 120 where the fluorescent portion 122 is formed may not coincide with each other.

  Again referring to FIG. 1, light emitting device 100 further includes an excitation light source 140.

  The excitation light source 140 irradiates the excitation light LT toward the internal point (focal point CP1).

  Note that the internal point irradiated with the excitation light LT does not have to coincide with the focal point CP1. That is, the internal point may be a point in the vicinity of the focal point CP1. That is, the internal point irradiated with the excitation light LT is the focal point CP1 or a point near the focal point CP1. The excitation light LT is laser light. The excitation light LT is not limited to laser light, and may be other forms of light (for example, light emitted from an LED) as long as it is light for exciting the phosphor.

  The concave mirror 110 is formed with a light guide 111 for guiding the excitation light LT from the excitation light source 140 into the concave mirror 110. The light guide 111 is a hole. The width of the light guide 111 in the Z direction is 3 mm, for example.

  In addition, the light guide part 111 is not limited to a hole, For example, the transparent member which permeate | transmits a laser beam may be sufficient.

  The excitation light source 140 is arranged outside the excitation light source 140 so that the excitation light LT reaches the focal point CP1 along the X direction via the light guide 111. As described above, the rotation unit 120 is arranged so that the Z direction line passing through the focal point CP1 and the Z direction line passing through the center in the X direction of the portion of the rotation unit 120 where the fluorescent part 122 is formed coincide. Is done. Further, as described above, the rotating unit 120 rotates so that at least a part of the rotating unit 120 passes through the internal point (focal point CP1) of the concave mirror 110.

  That is, the excitation light source 140 passes through the internal point (focal point CP1) of the concave mirror 110 so that the excitation light LT is orthogonal to at least a part of the rotation unit 120 (for example, the peripheral portion of the rotation unit 120). To the internal point (focal point CP1).

  Thereby, the fluorescent part 122 is excited, and the fluorescent part 122 emits light from the front side surface and the back side surface of the fluorescent part 122. That is, the light emitting unit (fluorescent unit 122) emits light by the excitation light LT from the excitation light source 140. Note that the amount of light emitted from the light emitting unit (fluorescent unit 122) can be maximized by adopting a configuration in which the excitation light LT is irradiated so as to be orthogonal to the fluorescent unit 122.

  As described above, the support portion 121 is made of a transparent material. Therefore, the rotating unit 120 emits light from the front side surface and the back side surface of the rotating unit 120.

  That is, at least a part of the rotating part 120 (peripheral part of the rotating part 120) that passes through the internal point (focal point CP1) of the concave mirror 110 when the rotating part 120 rotates reaches the internal point (focus CP1) from the excitation light source 140. The light emitting unit (fluorescent unit 122) is provided so as to emit light from the front side surface and the back side surface of the rotating unit 120 by the excitation light LT.

  As shown in FIGS. 1 and 3, light from the front side surface and the back side surface of the rotating unit 120 is reflected in the Z direction by the inner surface (mirror) of the concave mirror 110. That is, the concave mirror 110 is disposed at a position that reflects light from the front surface and the back surface of the rotating unit 120.

  As described above, in the present embodiment, the light emitted from both the front side surface and the back side surface of the rotating unit 120 by the excitation light LT applied to the focal point CP1 of the concave mirror 110 is transmitted by the concave mirror 110 to the Z side. Reflect in the direction. That is, the light emitting device 100 emits light in the Z direction by effectively utilizing most of the light emitted from both the front side surface and the back side surface of the rotating unit 120.

  Therefore, efficient light collection can be realized.

  In the present embodiment, since laser light is used as excitation light, it is possible to irradiate a very small spot on the fluorescent portion 122 with laser light. Therefore, the light emitting part of the fluorescent part 122 can also be minimized. Moreover, since the light emission part of the fluorescence part 122 is located in the focus CP1 of the concave mirror 110, it can condense efficiently.

  In the configuration of this embodiment, since no dichroic layer is used, light is not reflected by the dichroic layer or the like, and light diffusion / attenuation does not occur.

  Further, when the rotating unit 120 in which the fluorescent part 122 is formed rotates, the fluorescent part 122 also rotates. Therefore, even if a very small spot of the fluorescent part 122 is irradiated with the laser beam, the temperature rise of the fluorescent part 122 can be prevented. As a result, the deterioration of the fluorescent part 122 over time can be suppressed without reducing the luminous efficiency of the fluorescent part 122.

  The position of the excitation light source 140 is not limited to the position shown in FIG. 1, and may be another position (for example, above the concave mirror 110) as long as the excitation light LT can be irradiated to the focal point CP <b> 1. Good.

<Variation 1 of the first embodiment>
Next, a light emitting device according to Modification 1 of the first embodiment will be described.

  FIG. 6 is a cross-sectional view showing a configuration of a light emitting device 100A according to Modification 1 of the first embodiment.

  FIG. 7 is a cross-sectional view showing a configuration of a light emitting device 100A according to Modification 1 of the first embodiment. Specifically, FIG. 7 is a cross-sectional view of the light emitting device 100A in the ZY plane.

  6 and 7, light emitting device 100A is different from light emitting device 100 in FIG. 1 in that concave mirror 110A is provided instead of concave mirror 110. Since the other configuration of light emitting device 100A is the same as that of light emitting device 100, detailed description will not be repeated.

  The concave mirror 110A is different in shape from the concave mirror 110. Since the other configuration of concave mirror 110A is the same as that of concave mirror 110, detailed description will not be repeated.

  That is, the concave mirror 110A opens with respect to the first direction as the Z direction. The concave mirror 110A is provided with a slit SL and a light guide unit 111. The diameter of the concave mirror 110A is, for example, 65 mm.

  The concave mirror 110A has a focal point CP21 outside the concave mirror 110A. For example, the focal point CP21 exists at a position where the distance d2 from the bottom surface of the concave mirror 110A to the focal point CP21 is 100 mm, for example. The concave mirror 110A has a focal point at the same position as the internal point CP2 inside the concave mirror 110A.

  That is, the concave mirror 110A has an elliptical shape having a focal point CP21 outside the concave mirror 110A. The shape of the concave mirror 110A is elliptical with at least one focal point inside the concave mirror 110A. Hereinafter, the internal focal point of the concave mirror 110A is also referred to as an internal focal point.

  FIG. 8 is a diagram showing the spectral reflection characteristics of the concave mirror. The concave mirror 110A is, for example, a concave mirror having the spectral reflection characteristics shown in FIG. In FIG. 8, the vertical axis indicates the reflectance, and the horizontal axis indicates the wavelength of light.

  Again referring to FIGS. 6 and 7, in light emitting device 100 </ b> A, as in light emitting device 100, rotating portion 120 is provided. Since the configuration of the rotating unit 120 has been described above, detailed description will not be repeated.

  An internal point CP2 is provided inside the concave mirror 110A. The internal point CP2 corresponds to the focal point CP1 of the concave mirror 110. For example, the internal point CP2 exists at a position where the distance d1 from the bottom surface of the concave mirror 110A to the internal point CP2 is, for example, 10 mm.

  That is, the rotating unit 120 rotates so that a part of the rotating unit 120 (for example, the fluorescent unit 122) passes through the internal point CP2 of the concave mirror 110A via the slit SL.

  Moreover, the excitation light source 140 irradiates the excitation light LT toward the internal point CP2.

  That is, the excitation light source 140 irradiates the internal point CP2 with the excitation light LT so that the excitation light LT is orthogonal to at least a part of the rotating unit 120 passing through the internal point CP2 of the concave mirror 110A.

  Thereby, the fluorescent part 122 is excited, and the fluorescent part 122 emits light from the front side surface and the back side surface of the fluorescent part 122. That is, the light emitting unit (fluorescent unit 122) emits light by the excitation light LT from the excitation light source 140.

  Note that the internal point CP2 irradiated with the excitation light LT may not coincide with the internal focal point of the concave mirror 110A. That is, the internal point CP2 may be a point near the internal focal point of the concave mirror 110A. That is, the internal point CP2 irradiated with the excitation light LT is an internal focal point or a point in the vicinity of the internal focal point.

  The support part 121 is made of a transparent material. Therefore, the rotating unit 120 emits light from the front side surface and the back side surface of the rotating unit 120.

  That is, at least a part of the rotating part 120 (peripheral part of the rotating part 120) that passes through the internal point CP2 of the concave mirror 110A when the rotating part 120 rotates is excited by the excitation light LT that reaches the internal point CP2 from the excitation light source 140. A light emitting unit (fluorescent unit 122) is provided so as to emit light from the front side surface and the back side surface of the rotating unit 120.

  As shown in FIGS. 6 and 7, light from the surface on the front side and the surface on the back side of the rotating unit 120 is reflected by the inner surface (mirror) of the concave mirror 110 </ b> A toward the focal point CP <b> 21. That is, the concave mirror 110 </ b> A is disposed at a position that reflects light from the front surface and the back surface of the rotating unit 120.

  As described above, in Modification 1 of the present embodiment, the light emitted from both the front side surface and the back side surface of the rotating unit 120 by the excitation light LT irradiated to the internal point CP2 of the concave mirror 110A, Reflected in the direction of the focal point CP21 by the concave mirror 110A. That is, the light emitting device 100 </ b> A emits light in the Z direction by effectively utilizing most of the light emitted from both the front side surface and the back side surface of the rotating unit 120. Therefore, efficient light collection can be realized.

(Variation 1 of rotating part)
In the light emitting devices 100 and 100A described above, the following rotating unit 120N may be used instead of the rotating unit 120.

  FIG. 9 is a diagram illustrating a configuration of a rotation unit 120N as an example.

  FIG. 9A is a plan view of the rotating unit 120N.

  FIG. 9B is a cross-sectional view of the rotating unit 120N.

  9A and 9B, the rotation unit 120N is different from the rotation unit 120 in FIG. 4 in that the rotation unit 120N includes a fluorescence unit 122N instead of the fluorescence unit 122. The rest of the configuration of rotating unit 120N is the same as rotating unit 120, and thus detailed description will not be repeated. In addition, the shape of the rotating part 120N is a planar shape (plate shape).

  The size and shape of the fluorescent part 122N are the same as those of the fluorescent part 122. The width of the fluorescent part 122N in FIG. 9A is, for example, 4 mm.

  The fluorescent portion 122N includes a red fluorescent region 122R, a green fluorescent region 122G, and a blue fluorescent region 122B. That is, the light emitting part (fluorescent part 122N) is formed of a first region (red fluorescent region 122R), a second region (green fluorescent region 122G), and a third region (blue fluorescent region 122B).

  The red fluorescent region 122R is made of the red phosphor described above. The green fluorescent region 122G is made of the green phosphor described above. The blue fluorescent region 122B is made of the blue phosphor described above. As the rotating unit 120N having such a configuration rotates, the rotating unit 120N sequentially emits red light, green light, and blue light by the excitation light LT from the excitation light source 140.

  That is, the first region (red fluorescent region 122R), the second region (green fluorescent region 122G), and the third region (blue fluorescent region 122B) respectively receive red light, green light, and blue light by the excitation light LT. To emit.

  In the following, a rotating unit that sequentially emits red light, green light, and blue light by excitation light is referred to as a three-color rotating unit.

(Variation 2 of rotating part)
Further, in the light emitting devices 100 and 100A described above, the following rotating unit 120A may be used instead of the rotating unit 120.

  FIG. 10 is a diagram illustrating a configuration of a rotating unit 120A as an example.

  FIG. 10A is a plan view of the rotating unit 120A.

  FIG. 10B is a cross-sectional view of the rotating unit 120A.

  With reference to FIG. 10A and FIG. 10B, the shape of the rotating portion 120A (support portion 121) is planar (plate shape). The rotating unit 120 </ b> A has a configuration in which a fluorescent part 122 is formed on the outer peripheral part (side part) of the support part 121. The shape of the rotating part 120A (supporting part 121) is circular. The support part 121 is made of a transparent material. The transparent material is, for example, glass, silicon, resin, or the like.

  A hole H10 is formed at the center of the rotating part 120A, as with the rotating part 120. A part of the shaft 131 of the motor 130 passes through the hole H10, and the shaft 131 and the rotating portion 120A are fixed.

  That is, the rotating unit 120A rotates about the axis 131 along the second direction (X direction) orthogonal to the first direction (Z direction) as the rotation axis.

  Thereby, the rotating unit 120A allows a part of the rotating unit 120A (for example, the fluorescent unit 122) to pass through the internal point (focal point CP1 or internal point CP2) of the concave mirror 110 (concave mirror 110A) via the slit SL. Rotate to.

  FIG. 11 is an enlarged view of an end portion of the rotating unit 120A. FIG. 11 is an enlarged view of an end portion of a rotating unit 120A provided in the light emitting device 100 as an example.

  Referring to FIG. 11, rotating portion 120A is arranged such that the Z-direction line passing through focal point CP1 and the Z-direction line passing through the center of rotating portion 120A in the X direction coincide. That is, the rotation unit 120A is arranged such that a Z-direction line passing through the center in the X direction of the rotation unit 120A passes through the focal point CP1.

  The arrangement of the rotation unit 120A is not limited to the above arrangement as long as the Z direction line passing through the focal point CP1 passes through the vicinity of the center of the rotation unit 120A in the X direction. That is, the Z-direction line passing through the focal point CP1 and the Z-direction line passing through the center of the rotating unit 120A in the X direction may not coincide with each other.

  When the rotating unit 120A is provided in the light emitting device 100A, in the description of FIG. 11 described above, the description will be made by replacing the focal point CP1 with the internal point CP2, and the detailed description will not be repeated.

  Hereinafter, a rotating unit that emits monochromatic light by excitation light is referred to as a monochromatic rotating unit. The monochromatic rotating unit is, for example, the rotating unit 120 in FIG. 4, the rotating unit 120A in FIG.

  In the following description, a monochromatic rotating part that emits red light by excitation light is referred to as a red rotating part. In the following, a monochromatic rotating part that emits green light by excitation light is referred to as a green rotating part. In the following, a monochromatic rotating part that emits blue light by excitation light is referred to as a blue rotating part. In the following, a monochromatic rotating part that emits white light by excitation light is referred to as a white rotating part.

(Variation 3 of the rotating part)
Note that the fluorescent part 122 of the rotating unit 120A in FIG. 10 may be configured by a red fluorescent region 122R, a green fluorescent region 122G, and a blue fluorescent region 122B, like the fluorescent unit 122N in FIG.

  Further, the fluorescent part 122N of FIG. 9 is not limited to three fluorescent regions, and may be configured by, for example, six fluorescent regions. In this case, in the fluorescent portion 122N, a red fluorescent region 122R, a green fluorescent region 122G, a blue fluorescent region 122B, a red fluorescent region 122R, a green fluorescent region 122G, and a blue fluorescent region 122B are formed in this order in the rotation direction. .

  Further, in the fluorescent portion 122N of FIG. 9, a non-light emitting portion may be provided between two adjacent fluorescent regions (for example, the red fluorescent region 122R and the green fluorescent region 122G). The non-light-emitting portion is a portion that does not include a light emitter and is a portion that does not emit light even when irradiated with excitation light.

  Further, in the rotating unit 120A, the place where the fluorescent unit 122 is provided is not limited to the outer peripheral portion of the rotating unit 120A, and may be the entire rotating unit 120A. In this case, the rotating unit 120A has a configuration in which phosphors are dispersed in silicon, for example. In this case, the rotating unit 120A has, for example, a configuration in which phosphors are dispersed in glass.

  Further, in the rotating unit 120 of FIG. 4, the place where the fluorescent unit 122 is provided is not limited to the peripheral portion of the rotating unit 120 (support unit 121), and may be the entire rotating unit 120 (support unit 121).

  Further, in the rotating unit 120N of FIG. 9, the place where the fluorescent unit 122N is provided is not limited to the peripheral portion of the rotating unit 120 (supporting unit 121), but may be the entire rotating unit as shown in FIG. In this case, a light emitting part is formed in the entire rotating part.

  In addition, the light emitting part formed in the entire rotating part may be a mixture of red phosphor, green phosphor and blue phosphor at substantially the same ratio. In this case, the fluorescent part of the rotating part emits white light when irradiated with excitation light. In other words, in this case, the light emitting unit emits white light by the excitation light LT.

  Moreover, the fluorescent part 122 of the rotating part 120 of FIG. 4 may be a mixture of red phosphor, green phosphor and blue phosphor at substantially the same ratio. In this case, the fluorescent part 122 of the rotating part 120 in FIG. 4 emits white light when irradiated with excitation light. That is, in this case, the fluorescent part 122 as the light emitting part emits white light by the excitation light. The rotating unit 120 configured to emit white light is a white rotating unit.

  Moreover, the fluorescent part 122 of the rotating part 120A in FIG. 10 may be a mixture of red, green, and blue phosphors at substantially the same ratio. In this case, the fluorescent part 122 of the rotating part 120A in FIG. 10 emits white light when irradiated with excitation light. The rotating unit 120A configured to emit white light is a white rotating unit.

  In the light-emitting device 100 or the light-emitting device 100A described above, the same effect as that of the first embodiment can be obtained even when the rotating unit described in Modifications 1 to 3 of the rotating unit is used instead of the rotating unit 120. be able to. That is, efficient light collection can be realized.

<Second Embodiment>
Next, in the second embodiment, a projector that uses the light emitting device according to the first embodiment and the first modification of the first embodiment as a light source will be described.

  FIG. 13 is a diagram showing a schematic configuration of a projector 35 according to the second embodiment. The projector 35 is a front projector that projects an image on a screen (not shown) installed in front of the projector 35.

  The projector 35 is, for example, a DLP projector, a liquid crystal projector, an LCOS (Liquid Crystal On Silicon) projector, or the like. The DLP projector is a projector using DMD. The liquid crystal projector is a projector using a liquid crystal panel. The LCOS projector is a projector using LCOS.

  FIG. 13 shows a state in which a top plate of a case 36 to be described later is removed.

  The projector 35 includes a lamp unit 27, an optical unit 37, a control unit 38, a projection lens 39, a cooling fan unit 40, and a power supply unit 41.

  The lamp unit 27, the optical unit 37, the control unit 38, the projection lens 39, the cooling fan unit 40, and the power supply unit 41 are accommodated in the housing 36.

  The lamp unit 27 is the light emitting device 100 or the light emitting device 100A described above. The lamp unit 27 irradiates the optical unit 37 with light.

  The optical unit 37 includes an illumination unit and an image forming unit (not shown). The illumination unit irradiates the image forming unit with incident light from the lamp unit 27. For example, the illumination unit decomposes incident light into three primary colors and irradiates the image forming unit with the decomposed light.

  The image forming unit modulates incident light from the illumination unit to form an image.

  The control unit 38 drives and controls the image forming unit and the like.

  The projection lens 39 enlarges and projects an optical image formed by being modulated by the image forming unit onto a screen (not shown).

  The power supply unit 41 converts electric power supplied from a commercial power supply into electric power suitable for the control unit 38 and the lamp unit 27, and supplies the converted electric power to the control unit 38 and the lamp unit 27.

  The cooling fan unit 40 cools the lamp unit 27 using a cooling fan.

  As described above, the projector 35 according to the second embodiment uses the light emitting device 100 or the light emitting device 100A. Therefore, it is possible to realize a projector that uses light emitted from a light emitting device that achieves efficient light collection.

<Modification of Second Embodiment>
Next, in the modification of the second embodiment, a projector different from the second embodiment using the light emitting device according to the first embodiment and the modification 1 of the first embodiment as a light source. Will be described.

  FIG. 14 is a diagram showing a schematic configuration of a projector 42 according to a modification of the second embodiment. The projector 42 is a rear projector that projects an image on the back surface of the screen.

  Referring to FIG. 14, projector 42 includes a transmission screen 44, a lamp unit 27, an optical unit (not shown), a projection lens, a mirror, a high-pressure discharge lamp lighting device, and the like. The lamp unit 27, the optical unit, the projection lens, the mirror, the high-pressure discharge lamp lighting device, and the like are housed in the housing 43.

  The lamp unit 27 is the light emitting device 100 or the light emitting device 100A described above.

  In the projector 42, the image projected from the projection lens and reflected by the mirror is projected on the back surface of the transmissive screen 44 and displayed as an image.

(Configuration example 1 of optical unit)
Next, the configuration of the optical unit included in the projector according to the second embodiment or a modification of the second embodiment will be described.

  FIG. 15 is a diagram illustrating a configuration of an optical unit 400 as an example. The optical unit 400 corresponds to, for example, the optical unit 37 and the lamp unit 27 in FIG.

  Referring to FIG. 15, the optical unit 400 includes light emitting devices 41R, 41G, and 41B, LCD (Liquid Crystal Display) units 420R, 420G, and 420B, a dichroic prism 430, and a projection lens 440.

  Each of the light-emitting devices 41R, 41G, and 41B corresponds to, for example, the light-emitting device 100 or the light-emitting device 100A that includes the above-described single-color rotation unit. In other words, the optical unit 400 included in the projector projector according to the second embodiment or the modification of the second embodiment includes a light emitting device.

  The light emitting device 41R includes an excitation light source 410R, a red fluorescent part 411R, and a concave mirror if not shown. The light emitting device 41G includes an excitation light source 410G, a green fluorescent part 411G, and a concave mirror if not shown. The light emitting device 41B includes an excitation light source 410B, a blue fluorescent part 411B, and a concave mirror if not shown.

  The concave mirror included in each of the light emitting devices 41R, 41B, and 41G is, for example, the concave mirror 110 or the concave mirror 110A.

  Excitation light sources 410R, 410G, and 410B irradiate red fluorescent part 411R, green fluorescent part 411G, and blue fluorescent part 411B with excitation light, respectively. Each of the excitation light sources 410R, 410G, and 410B corresponds to, for example, the excitation light source 140 in FIG.

  The red fluorescent part 411R, the green fluorescent part 411G, and the blue fluorescent part 411B correspond to the above-described red rotating part, green rotating part, and blue rotating part, respectively.

  The red light emitted from the red fluorescent part 411R by the excitation light is reflected by a concave mirror (not shown) in the light emitting device 41R, passes through the LCD part 420R, and reaches the dichroic prism 430.

  The green light emitted from the green fluorescent part 411G by the excitation light is reflected by a concave mirror (not shown) in the light emitting device 41G, passes through the LCD part 420G, and reaches the dichroic prism 430. The blue light emitted from the blue fluorescent part 411B by the excitation light is reflected by a concave mirror (not shown) in the light emitting device 41B, passes through the LCD part 420B, and reaches the dichroic prism 430.

  The dichroic prism 430 combines the three types of incident light and guides the combined light to the projection lens 440. The projection lens 440 corresponds to, for example, the projection lens 39 in FIG. The projection lens 440 projects the incident light onto an external screen (not shown).

  An image is displayed on the screen by the operation of each configuration described above.

  In addition, a lens may be provided in the light path in the optical unit 400, or an optical fiber may be provided.

(Configuration example 2 of optical unit)
Next, another configuration of the optical unit included in the projector according to the second embodiment or a modification of the second embodiment will be described.

  FIG. 16 is a diagram illustrating a configuration of an optical unit 400A as an example. The optical unit 400A corresponds to, for example, the optical unit 37 and the lamp unit 27 in FIG.

  Referring to FIG. 16, optical unit 400A includes light emitting device 41N instead of light emitting devices 41R, 41B, and 41G, half mirrors 451 and 452, and mirror 453, as compared with optical unit 400 of FIG. The difference is that 454 and 455 are further provided. Since the other configuration of optical unit 400A is the same as that of optical unit 400, detailed description will not be repeated.

  The light emitting device 41N corresponds to the light emitting device 100 or the light emitting device 100A including the above-described white rotating unit. That is, the optical unit 400A included in the projector according to the second embodiment or the modification of the second embodiment includes a light emitting device.

  The light emitting device 41N includes an excitation light source 410N, a white fluorescent part 411W, and a concave mirror if not shown. The concave mirror included in the light emitting device 41N is, for example, the concave mirror 110 or the concave mirror 110A.

  The excitation light source 410N irradiates the white fluorescent part 411W with excitation light. The excitation light source 410N corresponds to, for example, the excitation light source 140 in FIG. Further, the white fluorescent part 411W corresponds to the above-described white rotating part.

  The white light emitted from the white fluorescent part 411W is reflected by the excitation light by a concave mirror (not shown) in the light emitting device 41N, and the reflected white light is applied to the half mirror 451.

  Thereby, green light and red light are obtained. The red light is reflected by the mirror 453, passes through the LCD unit 420R, and reaches the dichroic prism 430.

  The green light is applied to the half mirror 452. Thereby, blue light is obtained. The green light passes through the LCD unit 420G by the half mirror 452, and reaches the dichroic prism 430.

  The blue light is reflected by the mirrors 454 and 455, passes through the LCD unit 420B, and reaches the dichroic prism 430.

  The dichroic prism 430 combines the three types of incident light and guides the combined light to the projection lens 440. Since the operation of projection lens 440 has been described above, description thereof will not be repeated. An image is displayed on the screen by the operation of each configuration described above.

  In addition, a lens may be provided in the optical path in the optical unit 400A, or an optical fiber may be provided.

(Configuration Example 3 of Optical Unit)
Next, another configuration of the optical unit included in the projector according to the second embodiment or a modification of the second embodiment will be described.

  FIG. 17 is a diagram illustrating a configuration of an optical unit 500 as an example. The optical unit 500 corresponds to an optical unit and a lamp unit in the DLP projector. That is, the optical unit 500 corresponds to, for example, the optical unit 37 and the lamp unit 27 in FIG.

  Referring to FIG. 17, the optical unit 500 includes a light emitting device 51, a DMD 520, and an irradiation lens 540. The light emitting device 51 corresponds to the light emitting device 100 or the light emitting device 100A including the above-described three-color rotating unit. That is, the optical unit 500 included in the projector in the second embodiment or the modification of the second embodiment includes a light emitting device.

  The light emitting device 51 includes an excitation light source 510, a fluorescent part 511, and a concave mirror if not shown. The concave mirror included in the light emitting device 51 is, for example, the concave mirror 110 or the concave mirror 110A.

  The excitation light source 510 irradiates the fluorescent part 511 with excitation light. The excitation light source 510 corresponds to, for example, the excitation light source 140 in FIG.

  The fluorescent unit 511 corresponds to, for example, the rotating unit 120N in FIG. 9 as a three-color rotating unit.

  The red light, the green light, and the blue light that are sequentially emitted from the fluorescent unit 511 by the excitation light are sequentially reflected by a concave mirror (not shown) in the light emitting device 51, and the reflected red light, green light, and blue light are transmitted by the DMD 520. The light is sequentially reflected and reaches the projection lens 540.

  The projection lens 540 sequentially projects incident red light, green light, and blue light onto an external screen (not shown). An image is displayed on the screen by the operation of each configuration described above.

  In addition, a lens may be provided in the optical path of the optical unit 500, or an optical fiber may be provided.

(Other variations)
As described above, the light-emitting device according to the present invention has been described based on the embodiments, but the present invention is not limited to these embodiments. Unless it deviates from the meaning of this invention, the form which carried out various deformation | transformation which those skilled in the art can think to this embodiment, or the structure constructed | assembled combining the component in different embodiment is also contained in the scope of the present invention. .

  For example, the light emitting device according to the first embodiment and the first modification of the first embodiment is applicable not only to a projector but also to other devices that use light. The other devices are lighting fixtures, automobile headlamps, and the like.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  INDUSTRIAL APPLICABILITY The present invention can be used as a light emitting device that can realize efficient light collection.

H10 Hole 35, 42 Projector 41B, 41G, 41N, 41R, 51, 100, 100A Light emitting device 110, 110A Concave mirror 111 Light guide unit 120, 120A, 120N Rotating unit 121 Support unit 122, 122N, 511 Fluorescent unit 122R Red fluorescent region 122G Green fluorescent region 122B Blue fluorescent region 140, 410B, 410G, 410N, 410R, 510 Excitation light source 400, 400A, 500 Optical unit

Claims (15)

A concave mirror that opens in a first direction;
An excitation light source that emits excitation light toward an internal point that is part of the space inside the concave mirror;
A rotating unit that rotates about an axis along a second direction orthogonal to the first direction as a rotation axis;
The rotating unit includes a light emitting unit that emits light by the excitation light from the excitation light source,
The concave mirror is provided with a slit,
The rotating part rotates so that at least a part of the rotating part passes through the slit and the internal point of the concave mirror.
At least a part of the rotating unit is provided with the light emitting unit so as to emit light from the front surface and the back surface of the rotating unit by the excitation light reaching the internal point from the excitation light source,
The concave mirror is disposed at a position that reflects light from a front side surface and a back side surface of the rotating unit. The light emitting device according to claim 1, wherein the slit is provided at a bottom portion of the concave mirror. The light emitting device according to claim 1, wherein the shaft is disposed outside the concave mirror. The rotating unit includes a support unit and the light emitting unit,
The shape of the support portion is circular,
The light emitting device according to claim 1, wherein the light emitting unit is formed on a peripheral edge of the support unit. The rotating unit includes a support unit and the light emitting unit,
The shape of the support portion is circular,
The light emitting device according to claim 1, wherein the light emitting part is formed on an outer peripheral part of the support part. The light emitting device according to claim 4, wherein the support portion is made of a transparent material. The light emitting device according to claim 1, wherein the light emitting unit is formed in the entire rotating unit. The light emitting device according to any one of claims 1 to 7, wherein the light emitting unit emits red light, green light, or blue light by the excitation light. The light emitting unit is formed of a first region, a second region, and a third region,
The light emitting device according to claim 1, wherein the first region, the second region, and the third region emit red light, green light, and blue light, respectively, by the excitation light. The light emitting device according to claim 1, wherein the light emitting unit emits white light by the excitation light. The said excitation light source irradiates the said excitation point to the said internal point so that the said excitation light may orthogonally cross with respect to at least one part of the said rotation part which passes along the said internal point of the said concave mirror. 2. The light emitting device according to item 1. The concave mirror has a parabolic shape having a focal point inside the concave mirror,
The light emitting device according to claim 1, wherein the internal point is the focal point or a point in the vicinity of the focal point. The shape of the concave mirror is an ellipsoid having at least one focal point inside the concave mirror,
The light emitting device according to claim 1, wherein the internal point is the focal point or a point in the vicinity of the focal point. The light emitting device according to claim 1, wherein the excitation light is laser light. A projector comprising the light emitting device according to claim 1.

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