JP2012198265A - Wavelength conversion device and projector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wavelength conversion device with a configuration for suppressing the adhesion of foreign matter.SOLUTION: A wavelength conversion device includes a circular disk 41 provided rotatably around a predetermined rotational axis, a luminous layer 42 provided in an annular region around the rotational axis on the circular disk 41, a motor 50 connected to the circular disk 41 for rotating the circular disk 41 around the rotational axis, and a ground line 55 connected to the motor 50, in which the luminous layer 42 is electrically conducted to the ground line 55 through the circular disk 41 and the motor 50 and the ground line 55 eliminates static electricity generated in the luminous layer 42 through the circular disk 41 and the motor 50.

Description

  The present invention relates to a wavelength conversion device and a projector.

  Conventionally, in a projector, a discharge lamp such as an ultra-high pressure mercury lamp is generally used as a light source. However, this type of discharge lamp has problems such as a relatively short life, difficulty in instantaneous lighting, and ultraviolet light emitted from the lamp deteriorates the liquid crystal light bulb. In view of this, a projector using a light source instead of a discharge lamp has been proposed.

  For example, the light source device of Patent Document 1 includes a laser light source that is a light source of excitation light (blue light) that excites a phosphor, and a phosphor that emits a plurality of color lights corresponding to the three primary colors of light. Fluorescence emitted by irradiating a plurality of phosphors with laser light while rotating the disc while arranging the phosphors of a plurality of types on the disc in the circumferential direction and dividing the region for each type. Is different for each hour. Thus, a light source device that emits white light by time-integrating a plurality of color lights and mixing the colors is obtained.

JP 2009-277516 A

  However, in the light source device as described above, if dust (foreign matter) adheres to the phosphor, the foreign matter blocks the excitation light, so that the conversion efficiency to fluorescence decreases, or the foreign matter blocks the fluorescence and is emitted to the outside. As the amount of light decreases, the performance may decrease. In addition, since the region of the phosphor that is irradiated with the excitation light is as high as about 100 ° C., there is a possibility that foreign matter will burn into the phosphor and deteriorate.

  This invention is made | formed in view of such a situation, Comprising: It aims at providing the wavelength converter which has the structure which suppresses adhesion of a foreign material. Another object of the present invention is to provide a projector capable of displaying an image with a stable light quantity by having such a wavelength conversion device.

  The inventor has repeatedly studied a technique for suppressing the adhesion of foreign matter to the light emitting element, and has come up with the idea that one factor of adhesion of foreign matter to the light emitting element is due to static electricity. That is, since the light emitting element rotating at high speed is charged by friction with air, it is considered that the electrostatic attraction generated by this static electricity attracts the foreign substance floating in the air to the light emitting element and adheres to the surface. The present invention has been completed by examining the removal of static electricity, which is the cause of adhesion, from the light emitting element.

  That is, in order to solve the above-described problem, the wavelength conversion device of the present invention is provided in a substrate provided rotatably around a predetermined rotation axis, and in an annular region around the rotation axis on the substrate. A light emitting layer provided in connection with the substrate, and a motor for rotating the substrate around the rotation axis; and a charge removing means connected to the motor, wherein the light emitting layer includes the substrate and the substrate. It is electrically connected to the static elimination means via a motor, and the static elimination means neutralizes static electricity generated in the light emitting layer via the substrate and the motor.

  According to this configuration, the static elimination means can eliminate the static electricity accumulated in the light emitting layer via the substrate and the motor, thereby suppressing the electrostatic adhesion of foreign matter to the light emitting layer. For this reason, it is possible to suppress deterioration such as burn-in of foreign matter on the light emitting layer, and a highly reliable wavelength conversion device can be obtained.

In the present invention, the substrate is light transmissive, has at least a first member provided in the annular region, has conductivity, and supports the first member from the inner peripheral side of the annular region. And a second member provided in connection with the motor, and the light emitting layer is preferably provided in contact with the second member on the substrate.
According to this configuration, it is possible to effectively suppress the adhesion of foreign matter to the light emitting layer in the transmissive wavelength conversion device.

In the present invention, the first member and the second member are formed of plate-shaped members, and the second member is stacked on one surface of the first member, and the light emitting layer includes the light emitting layer, It is desirable to be provided in contact with the side surface of the second member on the inner peripheral side of the annular region.
According to this configuration, the static electricity generated in the light emitting layer can be discharged well from the side surface of the second member, and the fluorescence generated in the light emitting layer is reflected by the side surface of the second member and guided forward (light emission direction). be able to.

In the present invention, it is preferable that the substrate includes a third member provided on one surface of the first member and having a surface facing the side surface of the second member.
According to this configuration, the fluorescence generated in the light emitting layer can be reflected by the side surface of the third member and guided forward (light emission direction).

In the present invention, it is desirable that at least the annular region of the substrate has light reflectivity.
According to this configuration, it is possible to effectively suppress the adhesion of foreign matter to the light emitting layer in the reflective wavelength conversion device.

In the present invention, it is desirable that the static eliminating means is connected to a housing of the motor.
According to this structure, since the freedom degree of the connection location of a static elimination means spreads, a design freedom spreads.

In the present invention, the light-emitting layer includes a fluorescent substance that emits fluorescence, and a base material that has optical transparency and embeds the fluorescent substance, and the base material has a surface resistivity of 10 ¹⁵ Ω. / □ or less is desirable.
According to this configuration, static electricity can be easily removed from the light emitting layer, and adhesion of foreign matter to the light emitting layer can be effectively suppressed.

In the present invention, the substrate preferably has a surface resistivity of 10 ¹¹ Ω / □ or less.
According to this configuration, it becomes easier to remove static electricity from the light emitting layer, and adhesion of foreign matter to the light emitting layer can be effectively suppressed.

According to another aspect of the invention, a projector includes: a light source device that includes the above-described wavelength conversion device; a light source that emits excitation light to a light-emitting layer included in the wavelength conversion device; and light that modulates light emitted from the light source device. And a projection optical system that projects light modulated by the light modulation element.
According to this configuration, by including the wavelength conversion device as described above, it is possible to provide a projector that can suppress deterioration of the light emitting element and can display an image with a stable light amount.

It is a schematic diagram which shows the wavelength converter and projector of this embodiment. It is a graph which shows the light emission characteristic of a light source and a light emitting layer. It is a schematic explanatory drawing of a polarization conversion element. It is a schematic explanatory drawing of the wavelength converter of 1st Embodiment. It is an equivalent circuit of a wavelength converter. It is a schematic explanatory drawing of the wavelength converter of 2nd Embodiment. It is a schematic explanatory drawing of the light emitting element of 2nd Embodiment. It is explanatory drawing explaining operation of an Example.

[First Embodiment]
Hereinafter, the wavelength converter and projector according to the first embodiment of the present invention will be described with reference to FIGS. In all the drawings below, the dimensions and ratios of the constituent elements are appropriately changed in order to make the drawings easy to see.

(projector)
FIG. 1 is a schematic diagram showing a wavelength conversion device 30 and a projector PJ of this embodiment. As shown in the figure, the projector PJ includes a light source device 100 having a wavelength conversion device 30, a color separation optical system 200, a liquid crystal light valve (light modulation element) 400R, a liquid crystal light valve 400G, a liquid crystal light valve 400B, a color synthesis element 500, A projection optical system 600 is included.

The projector PJ generally operates as follows. The light emitted from the light source device 100 is separated into a plurality of color lights by the color separation optical system 200. The plurality of color lights separated by the color separation optical system 200 are incident on the corresponding liquid crystal light valve 400R, liquid crystal light valve 400G, and liquid crystal light valve 400B and modulated. A plurality of color lights modulated by the liquid crystal light valve 400R, the liquid crystal light valve 400G, and the liquid crystal light valve 400B are incident on the color synthesis element 500 and synthesized. The light synthesized by the color synthesizing element 500 is enlarged and projected by a projection optical system 600 onto a screen SCR such as a wall or a screen, and a full-color projection image is displayed.
Hereinafter, each component of the projector PJ will be described.

  The light source device 100 has a configuration in which a laser light source 10, a condensing optical system 20, a wavelength conversion device 30, a collimating optical system 60, a lens array 120, a lens array 130, a polarization conversion element 140, and a superimposing lens 150 are arranged in this order. ing. The wavelength conversion device 30 includes a light emitting element 40, a motor 50 that rotates the light emitting element 40, and a ground wire (static elimination unit) 55 connected to the motor 50.

  The laser light source 10 emits blue (light emission intensity peak: about 445 nm, see FIG. 2A) laser light as excitation light for exciting a fluorescent material included in the light emitting element 40 described later. In FIG. 2A, reference numeral B denotes a color light component emitted from the laser light source 10 as excitation light. Note that a plurality of laser light sources 10 (three in the drawing) may be provided, or only one laser light source may be used. In addition, a laser light source that emits colored light having a peak wavelength other than 445 nm may be used as long as it has a wavelength that can excite a fluorescent material to be described later.

  The condensing optical system 20 includes a first lens 22 that is a plurality of convex lenses, and a second lens 24 that is a convex lens through which light through the plurality of first lenses 22 is incident in common. The condensing optical system 20 is disposed on the beam axis of the laser light emitted from the laser light source 10 and condenses the excitation light emitted from the plurality of laser light sources 10.

  The wavelength conversion device 30 transmits a part of the excitation light (blue light) emitted from the laser light source 10 and absorbs the remaining part to emit yellow light (peak of emission intensity: about 550 nm, see FIG. 2B). It has the function to convert to. The wavelength conversion device 30 will be described in detail later.

  The collimating optical system 60 includes a first lens 62 that suppresses the spread of light emitted from the wavelength conversion device 30 and a second lens 64 that substantially collimates the light incident from the first lens 62, and has a wavelength as a whole. The light emitted from the conversion device 30 is collimated. The first lens 62 and the second lens 64 are configured as convex lenses.

  The lens array 120 and the lens array 130 make the luminance distribution of light emitted from the collimating optical system 60 uniform. The lens array 120 includes a plurality of first small lenses 122, and the lens array 130 includes a plurality of second small lenses 132. The first small lens 122 has a one-to-one correspondence with the second small lens 132. The light emitted from the collimating optical system 60 is spatially divided and incident on the plurality of first small lenses 122. The first small lens 122 causes the incident light to form an image on the corresponding second small lens 132. Thereby, a secondary light source image is formed on each of the plurality of second small lenses 132. Note that the outer shapes of the first small lens 122 and the second small lens 132 are substantially similar to the outer shapes of the image forming regions of the liquid crystal light valve 400R, the liquid crystal light valve 400G, and the liquid crystal light valve 400B.

  The polarization conversion element 140 aligns the polarization state of the light L emitted from the lens array 120 and the lens array 130. As shown in FIG. 3, the polarization conversion element 140 includes a plurality of polarization conversion cells 141. The polarization conversion cell 141 has a one-to-one correspondence with the second small lens 132. The light L from the secondary light source image formed on the second small lens 132 enters the incident region 142 of the polarization conversion cell 141 corresponding to the second small lens 132.

  Each polarization conversion cell 141 is provided with a polarization beam splitter film 143 (hereinafter referred to as a PBS film 143) and a phase difference plate 145 corresponding to the incident region 142. The light L incident on the incident region 142 is separated by the PBS film 143 into P-polarized light L1 and S-polarized light L2 with respect to the PBS film 143. One of the P-polarized light L1 and the S-polarized light L2 (here, S-polarized light L2) is reflected by the reflecting member 144 and then enters the phase difference plate 145. The S-polarized light L2 that has entered the phase difference plate 145 is converted into the polarization state of the other polarization (here, P-polarized light L1) by the phase difference plate 145, becomes P-polarized light L3, and is emitted together with the P-polarized light L1. .

  The superimposing lens 150 superimposes the light emitted from the polarization conversion element 140 in the illuminated area. The light emitted from the light source device 100 is spatially divided and then superimposed, whereby the luminance distribution is made uniform and the axial symmetry around the light axis 100ax is enhanced.

  The color separation optical system 200 includes a dichroic mirror 210, a dichroic mirror 220, a mirror 230, a mirror 240, a mirror 250, a field lens 300R, a field lens 300G, a field lens 300B, a relay lens 260, and a relay lens 270. The dichroic mirror 210 and the dichroic mirror 220 are obtained by, for example, laminating a dielectric multilayer film on a glass surface. The dichroic mirror 210 and the dichroic mirror 220 have a characteristic of selectively reflecting color light in a predetermined wavelength band and transmitting color light in other wavelength bands. Here, the dichroic mirror 210 reflects green light and blue light, and the dichroic mirror 220 reflects green light.

  The light L emitted from the light source device 100 enters the dichroic mirror 210. The red light R of the light L enters the mirror 230 through the dichroic mirror 210, is reflected by the mirror 230, and enters the field lens 300R. The red light R is collimated by the field lens 300R and then enters the liquid crystal light valve 400R.

  Green light G and blue light B in the light L are reflected by the dichroic mirror 210 and enter the dichroic mirror 220. The green light G is reflected by the dichroic mirror 220 and enters the field lens 300G. The green light G is collimated by the field lens 300G and then enters the liquid crystal light valve 400G.

  The blue light B that has passed through the dichroic mirror 220 passes through the relay lens 260 and is reflected by the mirror 240, then passes through the relay lens 270, is reflected by the mirror 250, and enters the field lens 300B. The blue light B is collimated by the field lens 300B and then enters the liquid crystal light valve 400B.

  The liquid crystal light valve 400R, the liquid crystal light valve 400G, and the liquid crystal light valve 400B are configured by a light modulation device such as a transmissive liquid crystal light valve. The liquid crystal light valve 400R, the liquid crystal light valve 400G, and the liquid crystal light valve 400B are electrically connected to a signal source (not shown) such as a PC that supplies an image signal including image information. The liquid crystal light valve 400R, the liquid crystal light valve 400G, and the liquid crystal light valve 400B modulate the incident light for each pixel based on the supplied image signal to form an image. The liquid crystal light valve 400R, the liquid crystal light valve 400G, and the liquid crystal light valve 400B form a red image, a green image, and a blue image, respectively. The light (formed image) modulated by the liquid crystal light valve 400R, the liquid crystal light valve 400G, and the liquid crystal light valve 400B enters the color composition element 500.

The color composition element 500 is configured by a dichroic prism or the like. The dichroic prism has a structure in which four triangular prisms are bonded to each other. The surface to be bonded in the triangular prism becomes the inner surface of the dichroic prism. On the inner surface of the dichroic prism, a mirror surface that reflects red light and transmits green light and a mirror surface that reflects blue light and transmits green light are formed orthogonal to each other. The green light incident on the dichroic prism is emitted as it is through the mirror surface. The red light and blue light incident on the dichroic prism are selectively reflected or transmitted by the mirror surface and emitted in the same direction as the emission direction of the green light. In this way, the three color lights (images) are superimposed and combined, and the combined color light is enlarged and projected onto the screen SCR by the projection optical system 600.
The projector PJ of this embodiment has the above configuration.

(Wavelength converter)
The wavelength conversion device 30 employs a configuration that suppresses adhesion of foreign matters such as dust to the light emitting element 40. The inventor has repeatedly studied a technique for suppressing the adhesion of foreign matter to the light emitting element 40, and has come up with the idea that one factor for the adhesion of foreign matter to the light emitting element 40 is due to static electricity. That is, the light emitting element 40 rotating at a high speed is charged by friction with air, and the generated electrostatic attraction attracts the foreign matter floating in the air to the light emitting element 40 and contributes to the adhesion of the foreign matter to the surface. Based on this idea, we examined a configuration that suppresses electrostatic attraction.

  In response to such a problem, the wavelength conversion device 30 according to the present embodiment has a ground wire (static elimination means) 55 that neutralizes the light emitting element 40 and adopts a configuration that can remove static electricity that is a cause of foreign matter adhesion. Yes. In the wavelength conversion device 30, the light emitting element 40 and the motor 50 are provided so as to be electrically connected, and a ground wire 55 is attached to the motor 50. That is, the ground wire 55 removes static electricity accumulated in the light emitting element 40 via the motor 50 and drops the potential of the light emitting element 40 to the ground.

  FIG. 4 is a schematic explanatory view of the wavelength conversion device 30, FIG. 4A is a plan view mainly showing the light emitting element 40, and FIG. 4B is a line segment AA in FIG. 4A. FIG. 4C is a schematic view of the light emitting layer 42 included in the light emitting element 40 of the wavelength conversion device 30. The light emitting layer 42 has a function of absorbing excitation light and converting it into fluorescence.

  As shown in FIGS. 4A and 4B, the light emitting element 40 includes a disk (substrate) 41 and a light emitting layer 42 formed continuously on the disk 41 in the circumferential direction. The disc 41 includes an annular first member 41a having light transmittance, a conductive second member 41b having a circular shape in plan view, and an annular third member 41c.

  In the disc 41, the first member 41a, the second member 41b, and the third member 41c are arranged concentrically. The inner diameter of the third member 41c is larger than the diameter of the second member 41b. When the second member 41b and the third member 41c are arranged concentrically, the side surfaces of the second member 41b and the third member 41c face each other. The gap 41x is formed. The first member 41a is disposed so as to overlap the gap 41x in a plan view, and is provided so as to be stacked on the second member 41b and the third member 41c so as to close the gap 41x. A region surrounded by the first member 41a, the second member 41b, and the third member 41c forms an annular region AR in the present invention.

  Further, the disc 41 includes a first member 41a, and a wavelength selection film 44 formed between the second member 41b and the third member 41c. The light emitting layer 42 is provided on the wavelength selection film 44 exposed in the gap 41x so as to be in contact with at least the second member 41b.

  Such a light emitting element 40 is arranged such that the side of the disc 41 on which the light emitting layer 42 is not formed faces the condensing optical system 20 side, and the excitation light condensed by the condensing optical system 20 is arranged. The focal position is arranged so as to overlap the light emitting layer 42.

  The first member 41a is made of a material that transmits blue light that is excitation light, and for example, quartz glass, crystal, sapphire (single crystal corundum), transparent resin, or the like can be used. Among these, quartz glass, quartz, and sapphire, which are inorganic materials, are preferably used so as not to be deformed by heating with excitation light. In the present embodiment, quartz having high thermal conductivity is used as a material for forming the first member 41a, and the first member 41a is formed in an annular shape having an inner diameter of 3.5 mm, an outer diameter of 5.5 mm, and a width of 2.0 mm.

  The second member 41b is made of a conductive material, and for example, a metal material such as aluminum or copper can be used. In addition, if it has conductivity, for example, a material having a laminated structure in which the surface of a resin substrate is covered with a metal material, or a composite material in which a carrier imparting conductivity to a resin is mixed is used. It can also be used. Further, it is preferable to use a material whose surface has light reflectivity, for example, a metal material, because the fluorescence generated in the light emitting layer 42 can be reflected from the side surface and guided forward (in the light emission direction). In the present embodiment, aluminum that is easy to process is used as a material for forming the second member 41b, and the second member 41b is formed in a disc shape having a diameter of 4.0 mm with a hole to which the motor 50 is connected.

  As a material for forming the third member 41c, various materials such as a metal material, a resin material, glass, and quartz can be used. In particular, it is preferable to use a material whose surface has light reflectivity, for example, a metal material, because the fluorescence generated in the light emitting layer 42 can be reflected from the side surface and guided forward (light emission direction). In the present embodiment, aluminum that is easy to process is used as a material for forming the first member 41b, and the first member 41b is formed in an annular shape having an inner diameter of 5.0 mm, an outer diameter of 6.0 mm, and a width of 1.0 mm.

  The first member 41a, the second member 41b, and the third member 41c are arranged concentrically, and are fixed by applying a conductive adhesive to the overlapping portion and curing it.

  The light emitting layer 42 transmits a part of the excitation light (blue light) emitted from the laser light source 10 and absorbs the remaining part to produce yellow fluorescence (peak of emission intensity: about 550 nm, see FIG. 2B). Convert. The light emitted from the light emitting layer 42 forms white light by mixing blue excitation light and yellow fluorescence. 2B is a color light component that can be used as red light in the yellow light emitted from the light emitting layer 42. Similarly, the component indicated by G is green light. Available color light components.

  As shown in FIG. 4C, the light emitting layer 42 includes a base material 421 having light permeability, and a plurality of phosphor particles 422 that are embedded in the base material 421 and emit fluorescence. Further, the base material 421 may include a binder 423 and conductive particles 424 for controlling the resistivity of the binder 423.

As a material for forming the base material 421, a material having optical transparency and a surface resistivity of 10 ¹⁵ Ω / □ or less is used. The surface resistivity of the substrate 421 is preferably 10 ¹¹ Ω / □ or less. As such a material, for example, conductive silicone or a conductive paste-containing inorganic material can be used. Specifically, a silicone resin known as an LED sealing material can be used as the base material 421.

  Further, the surface resistivity of the base material 421 is set to a desired value by adjusting the blending amount of the conductive particles 424 by using the above-described forming material as the binder 423 and containing the conductive particles 424 in the binder 423. It is adjustable. As the conductive particle 424, a particle having light permeability or a particle diameter smaller than the wavelength of light in the visible light region can be used. Examples of the conductive particles 424 include tin oxide, tin-antimony oxide, and indium-tin oxide particles.

The phosphor particles 422 are particulate fluorescent substances that absorb excitation light emitted from the laser light source 10 shown in FIG. 1 and emit fluorescence. For example, the phosphor particle 422 contains a substance that emits fluorescence when excited by blue light having a wavelength of about 445 nm, and a part of the excitation light emitted by the laser light source 10 is shown in FIG. As described above, the light is converted into light including the red wavelength band to the green wavelength band and emitted. As such phosphor particles 422, those having an average particle diameter of about 1 μm to several tens of μm are known to exhibit high luminous efficiency. As the phosphor particles 422, a commonly known YAG (yttrium, aluminum, garnet) phosphor can be used. For example, a YAG phosphor having a composition represented by (Y, Gd) ₃ (Al, Ga) ₅ O ₁₂ : Ce having an average particle diameter of 10 μm (refractive index: about 1.8) can be used.

  Note that the material for forming the phosphor particles 422 may be one type, or a mixture of particles formed using two or more types of forming materials may be used as the phosphor particles 422.

  For example, the phosphor layer 422 and the base material 421 (a mixture of the binder 423 and the conductive particles 424) are mixed at a volume ratio of 1: 1, and the amount is controlled by a dispenser, and the gap is formed in the gap 41x. It can be formed by applying and curing. Thereby, the light emitting layer 42 is provided in contact with the side surfaces of the second member 41b and the third member 41c.

  Further, as shown in FIG. 4B, the light emitting element 40 has a spindle (shaft) 52 of the motor 50 connected to the center of the disc 41 (center of the second member 41 b) and passes through the center of the disc 41. It is provided to be rotatable about the normal line as a rotation axis.

  The motor 50 rotates the light emitting element 40 at, for example, 7500 rpm during use. In this case, the region (beam spot) irradiated with the excitation light on the light emitting element 40 moves at about 18 m / second. That is, the motor 50 functions as a position displacement unit that displaces the position of the beam spot on the light emitting element 40. Thereby, since excitation light does not continue irradiating the same position on the light emitting element 40, the thermal deterioration of an irradiation position can be prevented and a lifetime of an apparatus can be extended.

  Furthermore, the shaft 52 of the motor 50 and the housing 51 of the motor are formed of a conductive material. An example of such a material is stainless steel. A ground wire 55 is connected to the motor casing 51.

FIG. 5 is an equivalent circuit of the wavelength conversion device 30. In the wavelength conversion device 30, the light-emitting layer 42 is in contact with the second member 41b made of a conductive material (that is, in contact with the disk 41), and the disk 41 is in contact with the shaft 52 (that is, in contact with the shaft 52). It is in contact with the motor 50). Therefore, the light emitting layer 42 is configured to be electrically connected to the disc 41 and the motor 50. The ground wire 55 grounds static electricity accumulated in the light emitting layer 42 from the housing 51 of the motor. Thereby, the adhesion of foreign matter to the surface of the light emitting element 40 is suppressed.
The wavelength conversion device 30 of the present embodiment has the above configuration.

  According to the wavelength conversion device 30 configured as described above, the ground wire 55 neutralizes static electricity accumulated in the light emitting layer 42 of the light emitting element 40 via the disc 41 (second member 41 b) and the motor 50. . For this reason, it is possible to suppress adhesion of foreign matters to the light emitting element 40 and to suppress deterioration such as image sticking.

  In addition, according to the projector PJ having the above-described configuration, by including the wavelength conversion device 30, it is possible to suppress deterioration of the light emitting element 40 and display an image with a stable light amount.

  In the present embodiment, the first member 41a is annular. However, the first member 41a may be a disk-like member concentric with the second member 41b. When such a first member 41a is used, it is not necessary to cut out the inner peripheral side in order to form an annular shape, and the first member 41a can be easily processed. However, the weight of the entire disc 41 increases, and the load on the motor 50 increases. Therefore, the shape of the first member 41a may be determined according to the performance that is important.

  In the present embodiment, the second member 41b and the third member 41c are separate members. For example, the second member 41b and the third member 41c are not interposed through the light emitting layer 42. An electrically conductive configuration can also be employed. For example, when the annular region provided with the light emitting layer 42 is divided into a plurality of parts, the second member 41b and the third member 41c may be connected at the divided part. In that case, if the light emitting layer 42 is in contact with the third member 41c, the static electricity accumulated in the light emitting layer 42 is also removed from the third member 41c, so that it is more easily discharged.

[Second Embodiment]
FIG. 6 is an explanatory diagram of the wavelength conversion device 31 and the projector according to the second embodiment of the invention. The projector according to the present embodiment has the same configuration after the collimating optical system 60 of the light source apparatus 100 and the projector PJ shown in FIG. Therefore, in the drawing, only the configuration around the wavelength conversion device 31 that is a different part of the light source device 101 included in the projector according to the present embodiment is illustrated.

  The wavelength conversion device 31 of this embodiment is partly in common with the wavelength conversion device 30 of the first embodiment. The difference is that the wavelength converter 31 has a transmissive light emitting element, whereas the wavelength converter 31 has a reflective light emitting element. Therefore, in this embodiment, the same code | symbol is attached | subjected about the component which is common in 1st Embodiment, and detailed description is abbreviate | omitted.

  The light source device 101 includes a laser light source 10, a collimating optical system 70, a dichroic mirror 80, a collimating condensing optical system 90, a wavelength conversion device 31, and a collimating optical system (not shown), a lens array, a polarization conversion element, and a superimposing lens. They are arranged in order.

  Blue light B emitted from the laser light source 10 enters the collimating optical system 70. The collimating optical system 70 is disposed in the optical path from the laser light source 10 to the dichroic mirror 80. The collimating optical system 70 includes a first lens 71 and a second lens 72. In the figure, the first lens 71 and the second lens 72 are illustrated as being convex lenses, but the present invention is not limited to this. The collimating optical system 70 causes the blue light B to enter the dichroic mirror 80 in a substantially parallel state.

  The dichroic mirror 80 is configured to reflect blue light and transmit light having a longer wavelength than the blue light. The dichroic mirror 80 is disposed so as to intersect with the ray axis of the blue light B emitted from the laser light source 10 at an angle of 45 °, and reflects the incident blue light B toward the collimator condensing optical system 90. To do.

  The collimator condensing optical system 90 includes a first lens 91 and a second lens 92. In the drawing, the first lens 91 and the second lens 92 are illustrated as being convex lenses, but the present invention is not limited to this. The collimator condensing optical system 90 causes the blue light from the dichroic mirror 80 to be incident on the light emitting element 45 of the wavelength conversion device 31 in a substantially condensed state.

  The wavelength conversion device 31 includes a light emitting element 45, a motor 50 that rotates the light emitting element 45, and a ground wire 55 connected to the motor. As shown in FIG. 7, the light emitting element 45 has a circular shape in plan view, and a circular plate 46 in which the surface of the annular region AR has light reflectivity, and a light emitting layer 42 formed continuously on the circular plate 46 in the circumferential direction. And have. The surface of the disk 46 other than the annular region AR may have light reflectivity.

  In addition, the disk 46 is made of a conductive material, like the second member 41b of the first embodiment described above. For example, a metal material such as aluminum or copper can be used. In addition, if it has conductivity, for example, a material having a laminated structure in which the surface of a resin substrate is covered with a metal material, or a composite material in which a carrier imparting conductivity to a resin is mixed is used. It can also be used. In the present embodiment, aluminum that is easy to process is used as a material for forming the disk 46, and the disk 46 is formed in a disk shape having a diameter of 6.0 mm with a hole to which the motor 50 is connected.

  For example, the light emitting layer 42 is formed by mixing the above-described phosphor particles 422 and the base material 421 (a mixture of the binder 423 and the conductive particles 424) at a volume ratio of 1: 1, and controlling the amount with a dispenser. It can form by apply | coating to the cyclic | annular area | region of 4.0 mm inside diameter and 5.0 mm outside diameter on the board 46, and making it harden | cure.

  Note that a reflective film may be formed using a conductive material between the disk 46 and the light emitting layer 42.

  The blue light B condensed by the collimator condensing optical system 90 is condensed on the light emitting layer 42 and converted into yellow fluorescence. The generated fluorescence is substantially collimated by the collimator condensing optical system 90, passes through the dichroic mirror 80, and is incident on a collimating optical system (not shown) provided in the subsequent stage.

  Even in the wavelength conversion device 31 configured as described above, the ground wire 55 neutralizes static electricity accumulated in the light emitting layer 42 of the light emitting element 45 via the disk 46 and the motor 50. Therefore, it is possible to provide a wavelength conversion device that suppresses adhesion of foreign matter to the light emitting element 45.

  The preferred embodiments of the present invention have been described above with reference to the accompanying drawings, but it goes without saying that the present invention is not limited to such examples. Various shapes, combinations, and the like of the constituent members shown in the above-described examples are examples, and various modifications can be made based on design requirements and the like without departing from the gist of the present invention.

[Example]
Hereinafter, the present invention will be specifically described with reference to examples based on model experiments. In the model experiment, the effect of the present invention was verified by attaching a foreign substance to a light emitting element constituting a part of the wavelength conversion apparatus of the present invention under predetermined conditions and quantifying the adhered foreign substance.
In addition, this invention is not limited by these Examples.

(Foreign matter adhesion test)
FIG. 8 is an explanatory diagram for explaining an operation of attaching a foreign substance to the light emitting element. In the model experiment, phosphor particles 422 and a base material 421 (mixture of binder 423 and conductive particles 424) mixed on one surface of a 5 cm square aluminum substrate at a volume ratio of 1: 1 were formed by screen printing. A film sample provided as a light emitting layer was used as model sample A. At this time, the surface resistance value was measured and confirmed to be 10 ¹¹ Ω / □ or less. Further, a model sample B in which the conductive particles 424 were not mixed was used. The conductivity of the model sample B is estimated to be about 10 ¹⁵ Ω / □ as the resistance value of the binder 423.

  First, as shown in FIG. 8A, after 2 g of foreign matter X is arranged at the center of the floor surface in a sealed chamber C (60 cm × 60 cm × 60 cm), compressed air is sprayed toward the foreign matter X to chamber C A foreign object was wound inside. Further, the blower F (rotational speed: 3200 rpm) arranged along the wall in the chamber C was blown for 1 second to stir the air in the chamber C, thereby allowing foreign matters to float in the chamber C.

  Next, as shown in FIG. 8B, the model sample (light emitting element S) is arranged so that the light emitting layer faces the inside of the chamber C at a position 20 cm from the floor surface of the wall surface facing the wall surface on which the blower F is arranged. ) Was placed. When installing the light-emitting element S, a ground wire was connected to the substrate to drop the potential of the substrate to the ground. Then, using the air blower F (rotation speed: 3200 rpm), it ventilated for 15 minutes toward the light emitting element S, and the foreign material was made to adhere to the surface of the light emitting element. The experimental environment was a temperature of 22 ° C. to 23 ° C. and a humidity of 36% to 40%.

  In the experiment, cotton linter (manufactured by Japan Air Cleaners Association) was used as the fiber-based foreign material, and Kanto Loam fired product (1-7 kinds of test powder, JIS-Z8901) was used as the dust-based foreign material. Then, an adhesion test was performed for each of these two types of foreign matters.

(Quantification of adhered foreign matter)
With respect to the light-emitting element S to which foreign matters were attached in this manner, an enlarged photograph of the foreign matter attachment surface was taken using a microscope. The photographed photograph was binarized with the background color black and the foreign matter white. Then, from the ratio of the number of data corresponding to the foreign matter (number of dots on the screen) to the total number of data of the photographed photo (total number of dots on the screen), the ratio of the adhered area of foreign matter in the field of view (occupation area ratio) Calculated.

  In the same manner, measurement was performed three times for each type of foreign matter, and an average value was calculated and adopted as an evaluation result. The measurement was performed for both the model sample A and the model sample B as the light emitting element S, and the result for the sample A was set as Example 1, and the result for the model sample B was set as Example 2.

(Comparative example)
Using the sample sample A as the light-emitting element S, and the light-emitting element S arranged in the chamber, except that no measures are taken to drop the potential to the ground, in the same manner as in the example, the occupied area ratio of the foreign matter attached to the light-emitting element S Was calculated.

  Table 1 below shows the evaluation results.

As a result of the measurement, the light-emitting element S of Examples 1 and 2 in which the potential was dropped to the ground decreased the amount of adhesion to both the fiber-based and dust-based foreign matters. Further, by comparing Example 1 and Example 2, it was confirmed that Sample A having a surface resistivity of 10 ¹¹ Ω / □ or less has a smaller foreign matter adhesion amount.
Therefore, it was confirmed that adhesion of foreign matter to the light emitting element was suppressed by the present invention, and the usefulness of the present invention was confirmed.

DESCRIPTION OF SYMBOLS 10 ... Laser light source (light source), 30, 31 ... Wavelength converter, 41 ... Disc (board | substrate), 41a ... 1st member, 41b ... 2nd member, 41c ... 3rd member, 42 ... Light emitting layer, 50 ... Motor , 51, housing, 55, ground wire (static elimination means), 100, light source device, 400 R, 400 G, 400 B, liquid crystal light valve (light modulation element), 421, substrate, 422, phosphor, 600, projection optical system , AR ... annular region, PJ ... projector,

Claims (9)

A substrate provided rotatably around a predetermined rotation axis;
On the substrate, a light emitting layer provided in an annular region around the rotation axis;
A motor connected to the substrate and rotating the substrate around the rotation axis;
Neutralizing means connected to the motor,
The light emitting layer is electrically connected to the static elimination means via the substrate and the motor,
The wavelength conversion device according to claim 1, wherein the static elimination means neutralizes static electricity generated in the light emitting layer via the substrate and the motor. The substrate is light transmissive and includes at least a first member provided in the annular region;
Having conductivity, and supporting the first member from the inner peripheral side of the annular region, and having a second member connected to the motor,
The wavelength conversion device according to claim 1, wherein the light emitting layer is provided in contact with the second member on the substrate. The first member and the second member are formed of a plate-like member, and the second member is provided on one surface of the first member,
The wavelength conversion device according to claim 2, wherein the light emitting layer is provided in contact with a side surface of the second member on an inner peripheral side of the annular region.   4. The wavelength conversion device according to claim 3, wherein the substrate includes a third member that is provided on one surface of the first member and has a surface that faces a side surface of the second member.   The wavelength conversion device according to claim 1, wherein at least the annular region of the substrate has light reflectivity.   The wavelength conversion device according to claim 1, wherein the charge eliminating unit is connected to a housing of the motor. The light-emitting layer has a fluorescent material that emits fluorescence, and a base material that has light transmittance and embeds the fluorescent material,
The wavelength conversion device according to claim 1, wherein the substrate has a surface resistivity of 10 ¹⁵ Ω / □ or less. The wavelength conversion device according to claim 7, wherein the base material has a surface resistivity of 10 ¹¹ Ω / □ or less.   A light source device comprising: the wavelength conversion device according to any one of claims 1 to 8; a light source that emits excitation light to a light-emitting layer of the wavelength conversion device; and light emitted from the light source device. A projector comprising: a light modulation element that modulates; and a projection optical system that projects light modulated by the light modulation element.

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