JP2013057850A - Wavelength conversion element, light source device and projector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wavelength conversion element, a light source device and a projector capable of improving an efficiency for light utilization as a whole system including the wavelength conversion element.SOLUTION: A fluorescent body wheel 100 (wavelength conversion element) of this invention comprises: a substrate 31; a light-emitting element at least including a fluorescent body layer 36 arranged on one surface of the substrate 31; and a first reflection part 34a formed at least on a first side face of the fluorescent body layer 36 and configured to change a direction of travel of light travelling inside the fluorescent body layer so that an angle thereof with respect to a normal line of an exit surface from which fluorescent light is emitted from the light-emitting device becomes small.

Description

  The present invention relates to a wavelength conversion element, a light source device, and a projector, and more particularly to a phosphor wheel that generates fluorescence and can be suitably used for them.

  As one of light source devices used in a projector, a light source device that irradiates a phosphor with laser light as excitation light and generates fluorescence having a wavelength different from the excitation light has been proposed (see, for example, Patent Documents 1 and 2). ).

JP 2009-277516 A JP 2010-86815 A

  A conventional phosphor layer of a phosphor wheel that functions as a wavelength conversion element is provided in a wide range with respect to a spot of excitation light formed on the phosphor wheel. The phosphor (phosphor crystal) dispersed in the phosphor layer emits the generated fluorescence isotropically. Since the phosphor layer has a predetermined thickness, the fluorescent component having a large angle with respect to the surface normal of the phosphor wheel substrate propagates to the outside of the excitation light spot in the phosphor layer. . The fluorescence that has propagated outside the spot of the excitation light is further scattered by being incident on a phosphor existing ahead. When the fluorescence propagates toward the outside of the spot due to repeated scattering in the phosphor layer, the light emission area in the phosphor wheel increases. That is, etendue increases. The increase in the light emission area in the phosphor wheel increases the light that is not taken in by the optical system behind the light source device, and causes a reduction in the light utilization efficiency of the entire system including the phosphor wheel.

  The light emitted from the phosphor layer exhibits an angular distribution close to Lambert radiation. The light emitted from the phosphor layer at a large angle with respect to the normal of the phosphor emission surface of the phosphor layer is difficult to capture sufficiently by the pickup lens and the light guide provided on the emission side of the phosphor layer. As a result, the light utilization efficiency decreases.

  An object of the present invention is to solve at least one of the above-described problems and provide a wavelength conversion element, a light source device, and a projector capable of improving the light utilization efficiency of the entire system including the wavelength conversion element. To do.

  A wavelength conversion element according to the present invention is provided on a substrate, a light emitting element including at least a phosphor layer provided on one surface of the substrate, and at least a first side surface of the phosphor layer. And a first reflecting portion that changes a traveling direction of light traveling inside so that an angle with respect to a normal line of an emission surface from which the fluorescence is emitted from the light emitting element is small.

According to such a configuration, the first reflecting portion reflects the light traveling in parallel with the one surface of the substrate inside the phosphor layer, thereby limiting the light emitting region and suppressing an increase in the light emitting area in the phosphor layer. Can be made. That is, the light emitting region does not extend beyond the first reflecting portion.
Further, the first reflecting portion can change the traveling direction of the light traveling inside the phosphor layer so that an angle with respect to a normal line of an emission surface from which the fluorescence is emitted from the light emitting element is small. That is, the traveling direction of light can be changed so that the light ray angle with respect to the surface normal of the light emitting element exit surface, that is, the interface between the light emitting element and air, becomes small. Thus, since the light ray angle on the exit surface of the light emitting element is reduced, total reflection of light on the exit surface of the light emitting element is suppressed. In addition, since the emission angle of light emitted from the light emitting element is reduced, the amount of light taken in by the pickup lens and the light guide means is increased. Thereby, the fall of the light utilization efficiency as the whole system containing a wavelength conversion element can be suppressed.

  Moreover, as a preferable aspect of the wavelength conversion element described above, it is desirable that the substrate be rotatable about a rotation axis that intersects one surface of the substrate.

  According to this configuration, since the substrate can be rotated, when the excitation light is irradiated onto the substrate, the spot of the excitation light formed on the wavelength conversion element moves in time and is excited per unit area. The time for light irradiation is shortened. Thereby, the temperature rise of the fluorescent substance layer by irradiating a fluorescent substance layer with excitation light can be suppressed. As a result, it is possible to suppress a decrease in wavelength conversion efficiency accompanying a temperature increase of the phosphor layer.

  Moreover, as a preferable aspect of the wavelength conversion element described above, the first side surface is either one of a direction along a circle centering on the rotation axis of the substrate and a direction intersecting the circle. Desirably along the direction.

  When the first side surface is along a direction along a circle centered on the rotation axis of the substrate, an increase in the light emission area is suppressed in the radial direction of the circle, and the light beam angle emitted from the light emitting element is reduced. can do. In addition, when the first side surface is along a direction intersecting with a circle centered on the rotation axis of the substrate, an increase in the light emission area in the circumferential direction of the circle is suppressed, and light emitted from the light emitting element is reduced. The ray angle can be reduced.

  Moreover, as a preferable aspect of the wavelength conversion element described above, a traveling direction of light that is provided on the second side surface of the phosphor layer facing the first side surface and travels inside the phosphor layer is set. It is desirable to further include a second reflecting portion that changes the angle of the exit surface with respect to the normal line to be small.

  Thereby, the increase in the light emission area can be further suppressed. Furthermore, since the amount of light emitted from the light emitting element at a small light beam angle can be increased, the amount of light taken in by the pickup lens or the light guide means can be further increased.

  In addition, as a preferable aspect of the wavelength conversion element described above, a traveling direction of light that is provided on the third side surface of the phosphor layer intersecting the first side surface and travels inside the phosphor layer is set. A third reflecting portion that changes the angle of the emission surface with respect to the normal line to be small, and a fourth side surface of the phosphor layer that faces the third side surface, and is arranged inside the phosphor layer. It is desirable to further include a fourth reflecting portion that changes the traveling direction of the light that travels in such a manner that the angle with respect to the normal line of the exit surface becomes small.

  As a result, when the phosphor layer is irradiated with excitation light while rotating the wavelength conversion element around a predetermined rotation axis, the light emitting region is limited in both the radial direction and the circumferential direction of the circle around the rotation axis. Therefore, an increase in the light emission area can be further suppressed. In addition, the amount of light taken in by the pickup lens or the light guide means can be further increased.

  Moreover, as a preferable aspect of the wavelength conversion element described above, it is preferable that the light emitting element further includes a light transmission layer provided on the opposite side of the phosphor layer from the substrate.

  According to this configuration, since the light transmission layer is provided on the opposite side of the phosphor layer from the substrate, it is emitted from the phosphor layer to the outside of the substrate as compared with the case where the light transmission layer is not provided. The amount of light increases. This is because the critical angle at the interface between the phosphor layer and the light transmission layer is larger than the critical angle at the interface between the phosphor layer and air.

  Moreover, as a preferred embodiment of the wavelength conversion element described above, the phosphor layer has a binder in which the phosphor is dispersed, and the refractive index of the light transmission layer is the same as the refractive index of the binder. It is desirable that

  According to this configuration, the fluorescence emitted from the phosphor is not reflected at the interface between the phosphor layer and the light transmission layer and returned to the phosphor layer. Therefore, it is possible to suppress light loss and heat generation due to fluorescence absorption by the phosphor layer.

  Moreover, as a preferable aspect of the wavelength conversion element described above, it is desirable that the light transmission layer has a concavo-convex structure provided on the surface opposite to the phosphor layer.

  According to this configuration, by having the concavo-convex structure, reflection of light at the interface between the light transmission layer and air can be suppressed, and light can be efficiently extracted from the light transmission layer.

  Moreover, as a preferable aspect of the wavelength conversion element described above, it is desirable that the phosphor layer is provided on the surface of the substrate.

  By providing the phosphor layer on the surface of the substrate, the heat generated in the phosphor layer can be effectively dissipated to the outside.

  As a preferred embodiment of the wavelength conversion element described above, it is desirable that the phosphor layer is provided in a groove provided in the substrate.

  By providing the phosphor layer in the groove of the substrate, the material of the phosphor layer can be stably applied.

  Moreover, as a preferable aspect of the wavelength conversion element described above, it is desirable to further include a heat conduction member provided on the opposite side of the phosphor layer of the first reflecting portion.

  Thereby, the heat generated in the phosphor layer can be effectively dissipated.

  Moreover, as a preferable aspect of the wavelength conversion element described above, it is desirable that the substrate is made of metal.

Thereby, the heat generated in the phosphor layer can be effectively dissipated.

  Moreover, as a preferable aspect of the wavelength conversion element described above, a fluorescence that is provided between the substrate and the phosphor layer, transmits excitation light that excites the phosphor, and is emitted from the phosphor. It is desirable to have a wavelength separation layer that reflects light.

  The wavelength separation layer reflects the fluorescence traveling toward the incident surface of the excitation light through the phosphor layer. Thereby, when the excitation light is irradiated from the side opposite to the surface on which the phosphor layer of the substrate is provided, the wavelength conversion element can efficiently emit fluorescence.

  Moreover, as a preferable aspect of the wavelength conversion element described above, it is provided between the substrate and the phosphor layer, and reflects excitation light that excites the phosphor and fluorescence emitted from the phosphor. It is desirable to have a reflective layer.

  Thereby, when the phosphor is irradiated with the excitation light from the side opposite to the substrate, the wavelength conversion element can efficiently emit the fluorescence and a part of the excitation light.

  Furthermore, a light source device according to the present invention includes an excitation light source unit that emits excitation light, and the wavelength conversion element that emits fluorescence when irradiated with the excitation light.

  Accordingly, it is possible to provide a light source device that has high light use efficiency as a whole system including the light source device and can obtain desired color light.

  Further, as a preferable aspect of the light source device described above, the excitation light spot formed on the wavelength conversion element in a cross section in a radial direction of a circle centering on a rotation axis intersecting one surface of the substrate is used. It is desirable that the size is substantially the same as or smaller than the width of the incident surface of the excitation light to the light emitting element.

  As a result, the incident position of the excitation light, that is, the spot of the excitation light formed on the wavelength conversion element does not protrude from the incident surface of the excitation light on the light emitting element, so that the allowable range of shake due to rotation of the wavelength conversion element is increased. can do.

  Moreover, as a preferable aspect of the light source device described above, a drive unit that drives the wavelength conversion element so that the spot moves in time on the wavelength conversion element, and the drive unit includes the wavelength conversion element. It is desirable to further include a correction unit that corrects at least one of the relative positional relationship between the phosphor layer and the spot and the size of the spot when driving.

  If the wavelength conversion element is driven so that the excitation light spot moves temporally on the wavelength conversion element by the drive unit, the temperature rise of the phosphor layer can be suppressed, and the wavelength conversion efficiency associated with the temperature rise of the phosphor layer can be suppressed. Reduction can be suppressed. However, if the phosphor layer is displaced when the drive unit drives the wavelength conversion element, the amount of excitation light incident on the phosphor layer varies with time, and the amount of light emitted from the phosphor layer. Varies over time. On the other hand, according to the above configuration, since the correction unit that corrects the positional deviation of the phosphor layer is provided, temporal variation in the amount of light emitted from the phosphor layer can be reduced. . In addition, a decrease in excitation light incident on the phosphor layer is suppressed, and a sufficient amount of light emitted from the phosphor layer can be secured. Moreover, it can also reduce that the utilization efficiency of excitation light reduces.

  Moreover, as a preferable aspect of the light source device described above, the wavelength conversion element is rotatable about a rotation axis intersecting with one surface of the substrate, and the phosphor layer is formed on the one surface of the substrate. It is desirable to provide along the circle centering on the rotating shaft.

  According to this configuration, since the substrate is rotatable, when the excitation light is irradiated on the phosphor layer, the spot of the excitation light moves in time on the wavelength conversion element. Therefore, the time for which the excitation light is irradiated per unit area is shortened. Thereby, the temperature rise of the fluorescent substance layer by irradiating excitation light to a fluorescent substance layer can be suppressed, and the fall of the wavelength conversion efficiency accompanying the temperature rise of a fluorescent substance layer can be suppressed.

  Moreover, as a preferable aspect of the light source device described above, the correction unit includes a first correction unit that corrects a positional shift of the phosphor layer in a direction perpendicular to an optical axis direction of the excitation light. Is desirable.

  According to this configuration, since the spot of the excitation light does not easily protrude outside the incident surface of the excitation light to the light emitting element, the excitation light can be used efficiently. Therefore, a sufficient amount of light emitted from the phosphor layer can be secured.

  In a preferred aspect of the light source device described above, the correction unit corrects the spot size by correcting the positional deviation of the phosphor layer in the optical axis direction of the excitation light. It is desirable to provide a correction unit.

  According to this configuration, since the spot of the excitation light does not easily protrude outside the incident surface of the excitation light to the light emitting element, the excitation light can be used efficiently. Therefore, a sufficient amount of light emitted from the phosphor layer can be secured.

  Moreover, as a preferable aspect of the light source device described above, the light source device further includes a detection unit that detects an amount of positional deviation of the phosphor layer, and the correction unit is configured to detect the position based on a detection result of the detection unit. It is desirable to correct the deviation.

  According to this configuration, since the detection unit that detects the amount of displacement of the phosphor layer is included, the displacement can be appropriately corrected based on the detection result of the detection unit.

  Moreover, as a preferable aspect of the light source device described above, the light source device further includes a data storage unit that stores data indicating the amount of positional deviation of the phosphor layer, and the correction unit is stored in the data storage unit. It is desirable to correct the positional deviation based on the data.

  According to this configuration, since the data storage unit that stores data indicating the amount of positional deviation of the phosphor layer is provided, the deviation can be corrected with a simple configuration based on the data.

  In a preferred embodiment of the light source device described above, the substrate is rotatable about a rotation axis that intersects one surface of the substrate, and the first side surface is a circle centered on the rotation axis. The wavelength conversion element is provided on the second side surface of the phosphor layer facing the first side surface, and transmits light traveling in the phosphor layer in parallel with the substrate to the substrate. A second reflection part that reflects in the reverse direction is further provided, the pulse frequency at which the excitation light is emitted by the excitation light source part is F (Hz), and the rotation speed of the wavelength conversion element is m (rps). , F is preferably an integer multiple of m.

  According to this configuration, the excitation light source unit can appropriately make the excitation light incident on the phosphor layer provided between the first reflection unit and the second reflection unit in the circumferential direction. it can.

  Furthermore, a projector according to the present invention is characterized in that the light emitted from the light source device is modulated in accordance with an image signal and projected.

  Thereby, the projector can suppress the fall of the light utilization efficiency as the whole system.

FIG. 1 is a schematic configuration diagram of a projector according to a first embodiment of the invention. FIG. 2 is a diagram showing the configuration of the phosphor wheel. FIG. 3 is a cross-sectional view of the phosphor wheel. FIG. 4 is a cross-sectional view of a main part of the phosphor wheel according to the first modification of the first embodiment. FIG. 5 is a cross-sectional view of a main part of the phosphor wheel according to the second modification of the first embodiment. FIG. 6 is a schematic configuration diagram of a projector according to the second embodiment of the invention. FIG. 7 is a plan view of the phosphor wheel. FIG. 8 is a cross-sectional view of a main part of the phosphor wheel. FIG. 9 is a cross-sectional view of a main part of the phosphor wheel. FIG. 10 is a plan view of the filter. FIG. 11 is a cross-sectional view of a main part of the phosphor wheel according to the third embodiment of the present invention. FIG. 12 is a diagram illustrating an illumination apparatus according to Embodiment 3 of the present invention. FIG. 13 is a schematic configuration diagram of a projector according to a fourth embodiment of the invention. FIG. 14 is a schematic configuration diagram of a projector according to the fifth embodiment of the invention. FIG. 15 is a diagram showing the configuration of the phosphor wheel and the pickup lens. FIG. 16 is a cross-sectional view of a main part of the phosphor wheel. FIG. 17 is a cross-sectional view of a main part of the phosphor wheel according to the first modification of the fifth embodiment. FIG. 18 is a plan view of a phosphor wheel according to the second modification of the fifth embodiment. FIG. 19 is a cross-sectional view of a main part of the phosphor wheel. FIG. 20 is a cross-sectional view of the main part of the phosphor wheel according to the third modification of the fifth embodiment. FIG. 21 is a cross-sectional view of a main part of the phosphor wheel according to the fourth modification of the fifth embodiment. FIG. 22 is a plan view of a phosphor wheel according to Embodiment 6 of the present invention. FIG. 23 is a perspective view of one unit structure. FIG. 24 is a cross-sectional view of the main part of the phosphor wheel in the circumferential direction. FIG. 25 is a cross-sectional view of main parts of a phosphor wheel according to Example 7 of the present invention. FIG. 26 is a diagram illustrating an example of a light source device using a phosphor wheel. FIG. 27 is a schematic configuration diagram of a projector according to an eighth embodiment of the invention. FIG. 28 is a schematic configuration diagram of a projector according to the ninth embodiment of the invention. FIG. 29 is a schematic configuration diagram of a projector according to a tenth embodiment of the invention.

  Embodiments of the present invention will be described below in detail with reference to the drawings.

[Example 1]
FIG. 1 is a schematic configuration diagram of a projector 1 according to a first embodiment of the invention. The light source device 10 emits illumination light including red (R) light, green (G) light, and blue (B) light. The light source device 10 includes a laser diode array 2, a condenser lens 4, a phosphor wheel 100 that functions as a wavelength conversion element, and a pickup lens 6.

The laser diode array 2 is composed of a plurality of laser diodes 3 arranged in an array. The laser diode array 2 functions as a pumping light source unit that emits the pumping light 60. The excitation light 60 is, for example, B light having a wavelength near 450 nm. The condensing lens 4 functions as a condensing optical system that condenses the excitation light 60 emitted from the laser diode array 2 in the phosphor wheel 100.
The phosphor wheel 100 emits fluorescence having a wavelength different from that of the excitation light 60 when the excitation light 60 is irradiated. The pickup lens 6 is provided on the optical path of the excitation light 60. The pickup lens 6 captures the fluorescence emitted from the phosphor wheel 100 and the excitation light 60 transmitted through the phosphor wheel 100 and advances it to the collimating optical system 11.

  The collimating optical system 11 condenses the light from the light source device 10 on the rod integrator 12. The rod integrator 12 multi-reflects the incident light internally to make it uniform, and emits the uniformed light toward the superimposing lens 13. The superimposing lens 13 superimposes the light beam divided into a plurality by the rod integrator 12 using a spatial light modulator.

  The first dichroic mirror 14 reflects R light and G light incident from the superimposing lens 13 and transmits B light. The B light transmitted through the first dichroic mirror 14 has its optical path bent by reflection by the reflection mirror 16 and is incident on the incident-side polarizing plate 20B. The light transmitted through the incident side polarizing plate 20B enters the liquid crystal panel 21B. The liquid crystal panel 21B constitutes a spatial light modulation device that modulates the B light according to the image signal. The light transmitted through the liquid crystal panel 21B is incident on the exit-side polarizing plate 22B. The B light transmitted through the exit side polarizing plate 22B enters the cross dichroic prism 23.

  The R light and G light reflected by the first dichroic mirror 14 enter the second dichroic mirror 15. The second dichroic mirror 15 reflects G light and transmits R light. The G light whose optical path is bent by the reflection at the second dichroic mirror 15 enters the incident-side polarizing plate 20G. The G light transmitted through the incident side polarizing plate 20G is incident on the liquid crystal panel 21G. The liquid crystal panel 21G constitutes a spatial light modulation device that modulates G light according to an image signal. The light transmitted through the liquid crystal panel 21G is incident on the exit-side polarizing plate 22G. The G light transmitted through the exit-side polarizing plate 22G enters the cross dichroic prism 23.

  The R light that has passed through the second dichroic mirror 15 has its optical path bent by reflection by the reflection mirror 17 and enters the relay lens 18. The R light that has passed through the relay lens 18 has its optical path bent due to reflection by the reflection mirror 19, and is incident on the incident-side polarizing plate 20R. The R light transmitted through the incident side polarizing plate 20R enters the liquid crystal panel 21R. The liquid crystal panel 21R constitutes a spatial light modulation device that modulates R light according to an image signal. The light transmitted through the liquid crystal panel 21R is incident on the exit-side polarizing plate 22R. The R light transmitted through the exit side polarizing plate 22R enters the cross dichroic prism 23.

  The cross dichroic prism 23 that is a color combining optical system combines the light modulated by each spatial light modulation device into image light, and advances it to the projection optical system 24. The projection optical system 24 projects the image light combined by the cross dichroic prism 23 onto a screen (not shown).

FIG. 2A is a plan view of the phosphor wheel 100 that functions as a wavelength conversion element, and is a plan view of the phosphor wheel 100 as viewed from the side where the structure 32 is provided. FIG. 2B is a cross-sectional view of the phosphor wheel 100 and includes a center position of the phosphor wheel 100. 2 (a) and 2 (b), the wheel motor 33 is mounted on the phosphor wheel 100, and in FIG. 2 (b), the pickup lens 6 is further combined with the phosphor wheel 100. .
FIG. 3 is a cross-sectional view taken along the line AA ′ in the radial direction of the circle centering on the rotation axis R of the phosphor wheel 100 in FIG.

  The phosphor wheel 100 includes a wheel substrate 31 that can rotate around a rotation axis R and a structure 32.

  As shown in FIG. 2, the wheel substrate 31 is a circular plate-like member, and is made of a transparent member such as glass. In the center of the wheel substrate 31, an opening through which the columnar wheel motor 33 passes is provided. The wheel substrate 31 is integrated with the wheel motor 33 by mounting the wheel substrate 31 to the wheel motor 33 at the opening. The wheel substrate 31 rotates with the center position of the circular shape as the rotation axis R by driving the wheel motor 33. That is, the wheel substrate 31 is rotatable about a rotation axis R that intersects one surface of the wheel substrate 31.

  As shown in FIG. 3, in this embodiment, the structural body 32 includes a phosphor layer 36, a first reflecting portion 34a, and a second reflecting portion 34b. The phosphor layer 36 includes a plurality of particulate phosphors 1000. The phosphor layer 36 functions as a light emitting element. The excitation light 60 enters the phosphor layer 36 from the incident surface 36a side of the phosphor layer 36 and excites the phosphor 1000. The excited phosphor 1000 generates fluorescence. The fluorescence emitted from the phosphor 1000 and a part of the excitation light 60 transmitted through the phosphor layer 36 are emitted from the emission surface 36 b of the phosphor layer 36. Hereinafter, in Examples 1 to 4, the emission surface 36b refers to a surface from which the fluorescence emitted from the phosphor 1000 is emitted from the phosphor layer 36 into the air among the plurality of surfaces of the phosphor layer 36. .

A recess 37 is provided on one surface of the wheel substrate 31, that is, the surface 31 a of the wheel substrate 31 opposite to the surface 31 b on which the excitation light 60 is incident on the wheel substrate 31, and the structure 32 is disposed in the recess 37. Is provided. The emission surface 36b of the phosphor layer 36 and the surface 31a of the wheel substrate 31 are continuous with each other.
As shown in FIG. 2A, the structure 32 including the phosphor layer 36 forms a ring having a certain width in plan view. The ring formed by the phosphor layer 36 (structure 32) corresponds to the locus of the spot of the excitation light 60 obtained when the wheel substrate 31 rotates about the rotation axis R.

  In FIG. 3, the phosphor layer 36 includes a first side surface 35a and a second side surface 35b. The first side surface 35a and the second side surface 35b have a circular shape centered on the rotation axis R in plan view, and face each other. The first side surface 35 a is the side surface of the annular phosphor layer 36 on the wheel motor 33 side, and the second side surface 35 b is the side surface of the annular phosphor layer 36 on the outer edge side of the wheel substrate 31. In the present embodiment, the first side surface 35a and the second side surface 35b may be collectively referred to as the side surface 35 as appropriate.

  The first reflecting portion 34 a is provided on the first side surface 35 a of the phosphor layer 36, and the second reflecting portion 34 b is provided on the second side surface 35 b of the phosphor layer 36. In a cross section intersecting the first side surface 35a, for example, a cross section AA ′ along the radial direction of a circle centering on the rotation axis R, the distance between the first side surface 35a and the second side surface 35b is: The excitation light 60 increases from the incident surface 36a toward the fluorescence exit surface 36b. Therefore, the distance between the first reflection part 34a and the second reflection part 34b is also increased from the incident surface 36a of the excitation light 60 toward the fluorescence emission surface 36b.

  In the present embodiment, the first reflecting portion 34a and the second reflecting portion 34b may be collectively referred to as the reflecting portion 34 as appropriate. In addition, in this specification, for convenience, the reflecting portion 34 provided in the above-described form is referred to as a tapered reflecting portion 34. Or it says that the reflection part 34 has a taper shape. The reflector 34 reflects the fluorescence and excitation light 60 emitted from the phosphor layer 36. As the reflection part 34, a highly reflective member, for example, a film made of a metal member is used.

  The dichroic film 38 is provided on the incident surface 36a between the wheel substrate 31 and the phosphor layer 36, and has a circular shape centering on the rotation axis R in plan view. The dichroic film 38 functions as a wavelength separation layer having a wavelength characteristic that transmits the excitation light 60 emitted from the laser diode array 2 and reflects the fluorescence emitted from the phosphor 1000.

The phosphor 1000 generates fluorescence including G light and R light when irradiated with the excitation light 60. A part of the excitation light 60 incident on the phosphor layer 36 is emitted from the emission surface 36b of the phosphor layer 36 toward the pickup lens 6 together with the fluorescence. As described above, the light source device 10 emits white illumination light by mixing the fluorescence including the G light and the R light and the excitation light 60 including the B light.
For example, a YAG phosphor is used as the phosphor. The phosphor layer 36 is obtained, for example, by applying a powdered phosphor 1000 and a binder to the wheel substrate 31 and thermally curing the mixture.

  A spot of excitation light 60 is formed on the incident surface 36 a of the phosphor layer 36. In the light source device 10, the spot diameter d1 of the excitation light 60 along the radial direction of the circle centered on the rotation axis R is substantially equal to the width M of the incident surface 36a or smaller than the width M of the incident surface 36a. Adjusted to Accordingly, it is possible to increase the allowable range of shake due to the rotation of the wavelength conversion element so that the incident position of the excitation light 60, that is, the spot of the excitation light formed on the wavelength conversion element does not protrude from the incident surface 36a.

  The excitation light 60 incident on the wheel substrate 31 passes through the wheel substrate 31 and the dichroic film 38 and enters the phosphor layer 36. A part of the excitation light 60 incident on the phosphor layer 36 excites the phosphor 1000, and the excited phosphor 1000 emits fluorescence. The fluorescence generated in the phosphor 1000 is emitted approximately isotropic around the light emission position.

  Light that travels inside the phosphor layer 36 in parallel with the surface 31a of the wheel substrate 31 or at a large angle with respect to the normal line N of the emission surface 36b of the phosphor layer 36 is reflected by the reflector 34. . Therefore, the propagation of fluorescence in the radial direction of the circle centered on the rotation axis R is limited, and the light emitting region is limited to the region between the first reflecting portion 34a and the second reflecting portion 34b. That is, the light emitting region does not extend beyond the first reflecting portion 34a. Further, the light emitting area does not extend beyond the second reflecting portion 34b. Therefore, an increase in the light emission area can be suppressed.

The fluorescence that has traveled inside the phosphor layer 36 toward the incident surface 36 a side of the wheel substrate 31 is reflected by the dichroic film 38 and proceeds in the direction of the exit surface 36 b of the phosphor layer 36. Therefore, the fluorescence emitted from the phosphor 1000 does not leak to the incident surface 36 a side of the wheel substrate 31 and can be efficiently emitted from the emission surface 36 b of the phosphor layer 36.
In addition, among the excitation light 60 transmitted through the phosphor layer 36 and the fluorescence emitted by the phosphor 1000, the component incident at an angle smaller than the critical angle with respect to the emission surface 36b of the phosphor layer 36 is phosphor. Injection from the layer 36 into the air.

By reflecting light in a direction opposite to the incident surface 36a side of the wheel substrate 31 by the tapered reflecting portion 34, the traveling direction of the light is changed so that the light ray angle with respect to the normal line N of the exit surface 36b becomes small. Can do. Therefore, the light ray angle at the exit surface 36b of the phosphor layer 36 is reduced, the total reflection of light at the exit surface 36b is suppressed, and the light traveling inside the phosphor layer 36 is air from the exit surface 36b of the phosphor layer 36. It becomes easy to inject.
Since the amount of light reflected by the emission surface 36b of the phosphor layer 36 and returning to the phosphor layer 36 is reduced, light loss and heat generation due to absorption of the fluorescence by the phosphor layer 36 are caused. It is suppressed.

Further, by reducing the emission angle (light ray angle) of the light emitted from the emission surface 36b of the phosphor layer 36, the amount of light taken in by the pickup lens 6 and the like can be increased.
Thus, the light use efficiency of the entire system of the projector 1 including the phosphor wheel 100 can be improved.

(Modification 1)
FIG. 4 is a cross-sectional view of the main part of the phosphor wheel according to the first modification of the present embodiment, and corresponds to the cross-sectional view of FIG. In the phosphor wheel 100 according to the first embodiment, the emission surface 36b of the phosphor layer 36 and the surface 31a of the wheel substrate 31 are provided to be continuous with each other. However, in the phosphor wheel 200 according to the present modification, The emission surface 36 b of the phosphor layer 36 is embedded in a recess 37 provided in the wheel substrate 31.

  The reflector 34 is sandwiched between the side surface 35 of the phosphor layer 36 and the wall surface of the recess 37. Further, the reflecting portion 34 is not provided only on the side surface 35 of the phosphor layer 36, but extends from the emission surface 36 b of the phosphor layer 36 to the vicinity of the surface 31 a of the wheel substrate 31 along the wall surface of the recess 37. Exist. In the present modification, the reflecting portion 34 extends from the emission surface 36 b of the phosphor layer 36 to the surface 31 a of the wheel substrate 31.

  According to the phosphor wheel 200 according to this modification, the following effects can be obtained in addition to the effects obtained in the phosphor wheel 100 according to the first embodiment.

  Of the light emitted from the emission surface 36 b of the phosphor layer 36, the light emitted at a large angle with respect to the normal line N is reflected by the reflecting portion 34 in the direction of the pickup lens 6. The amount of can be increased. Thereby, the light utilization efficiency as the whole system of the projector 1 including the phosphor wheel 200 can be further improved.

(Modification 2)
FIG. 5 is a cross-sectional view of the main part of the phosphor wheel according to the second modification of the present embodiment, and corresponds to the cross-sectional view of FIG. In the phosphor wheel 100 according to the first embodiment, the structure 32 is embedded in the concave portion 37 provided in the wheel substrate 31. However, in the phosphor wheel 300 according to the second modification, the structure 32 is formed on the wheel substrate 31. It is provided on the surface 31a.
According to the phosphor wheel 300 according to the present modification, in addition to the effects obtained in the phosphor wheel 100 according to the first embodiment, heat generated in the phosphor layer 36 can be effectively dissipated to the outside. An effect is also obtained.

(Modification 3)
In the phosphor wheel according to the first embodiment and the first and second modifications, the first reflecting portion 34a and the second reflecting portion 34b are provided, but only one of them may be provided. For example, when only the second reflecting portion 34b is provided, the fluorescent component that travels at a large angle with respect to the normal line N of the emission surface 36b of the phosphor layer 36 is reflected by the second reflecting portion 34b. Propagation in the outer direction of the wheel substrate 31 is limited. The light reflected by the second reflecting portion 34b travels while being scattered by the phosphor 1000 inside the phosphor layer 36, and eventually emerges from the exit surface 36b into the air. Therefore, even when only one of the first reflecting portion 34a and the second reflecting portion 34b is provided, the effect of improving the light utilization efficiency of the entire system can be obtained.

[Example 2]
A projector according to the second embodiment will be described with reference to FIGS. FIG. 6 is a schematic configuration diagram of a projector 600 according to the second embodiment of the invention. FIG. 7 is a plan view of the phosphor wheel 400. FIG. 8 is a view showing a cross section CC ′ of the phosphor wheel 400, and FIG. 9 is a view showing a cross section BB ′ of the phosphor wheel 400. FIG. 10 is a plan view of the filter 620.

  In the first embodiment, one annular structure 32 is provided on the wheel substrate 31, but in the phosphor wheel 400 according to the present embodiment, as shown in FIG. 7, a plurality of structures 32R and a plurality of structures 32R are provided. The structure 32 </ b> G is annularly arranged so as to surround the rotation axis R of the wheel substrate 31. Further, an opening 433 through which the columnar wheel motor 33 passes is provided. The structure 32R includes a phosphor layer 36R including a phosphor 1000R that emits red fluorescence when excited by the excitation light 60, and the structure 32G emits green fluorescence when excited by the excitation light 60. A phosphor layer 36G including the phosphor 1000G is provided. The excitation light 60 is blue light having a wavelength near 450 nm, as in the first embodiment.

  The structure 32R will be described with reference to FIGS. Since the structure 32G has the same structure as the structure 32R, the description of the structure 32G is omitted. The structure 32R includes a phosphor layer 36R, a first reflection part 34a, a second reflection part 34b, a third reflection part 84a, and a fourth reflection part 84b. In the phosphor layer 36R, particulate phosphor 1000R is dispersed. The excitation light 60 enters the phosphor layer 36R from the incident surface 36a side of the phosphor layer 36R, and excites the phosphor 1000R. The excited phosphor 1000R emits red fluorescence. A part of the excitation light 60 transmitted through the phosphor layer 36R and the fluorescence emitted by the phosphor 1000R are emitted from the emission surface 36b of the phosphor layer 36R.

  As shown in FIG. 8, the phosphor layer 36R includes a first side surface 35a and a second side surface 35b. The first side surface 35a and the second side surface 35b have a circular shape centering on the rotation axis R of the wheel substrate 31 in plan view, and face each other in the radial direction of the circle. The first side surface 35 a is a side surface of the phosphor layer 36 on the wheel motor 33 side, and the second side surface 35 b is a side surface of the phosphor layer 36 on the outer edge side of the wheel substrate 31. The first reflecting portion 34a is provided on the first side surface 35a of the phosphor layer 36R, and the second reflecting portion 34b is provided on the second side surface 35b of the phosphor layer 36R. Similar to the phosphor wheel 100 according to the first embodiment, the cross section intersecting the first side surface 35a, for example, the cross section CC ′ along the radial direction of the circle centering on the rotation axis R, the first side surface 35a and the first side surface The distance between the two side surfaces 35b increases from the incident surface 36a toward the exit surface 36b. Accordingly, the distance between the first reflecting portion 34a and the second reflecting portion 34b is also increased from the incident surface 36a toward the exit surface 36b.

  As shown in FIG. 9, the phosphor layer 36 </ b> R further includes a third side surface 85 a and a fourth side surface 85 b that extend in the radial direction of a circle centered on the rotation axis R of the wheel substrate 31. The third side surface 85a and the fourth side surface 85b face each other in the circumferential direction of the circle. The third reflecting portion 84a is provided on the third side surface 85a of the phosphor layer 36R, and the fourth reflecting portion 84b is provided on the fourth side surface 85b of the phosphor layer 36R. In a cross section intersecting the third side surface 85a, for example, a cross section BB ′ along the circumferential direction of the circle having the rotation axis R as the center, the distance between the third side surface 85a and the fourth side surface 85b is , And increases from the incident surface 36a toward the exit surface 36b. Accordingly, the distance between the third reflecting portion 84a and the fourth reflecting portion 84b also increases from the incident surface 36a toward the exit surface 36b.

  In the present embodiment, the first side surface 35a and the second side surface 35b may be collectively referred to as the side surface 35, and the third side surface 85a and the fourth side surface 85b may be collectively referred to as the side surface 85 as appropriate. In addition, the first reflecting portion 34a and the second reflecting portion 34b may be collectively referred to as the reflecting portion 34, and the third reflecting portion 84a and the fourth reflecting portion 84b may be collectively referred to as the reflecting portion 84 as appropriate. . Further, as in the first embodiment, the reflecting portion 34 and the reflecting portion 84 provided in the above-described form are referred to as a tapered reflecting portion. Or it says that the reflective part has a taper shape. Since the reflecting portion 34 and the reflecting portion 84 have a tapered shape, the fluorescence and excitation light 60 incident from the phosphor layer 36R are reflected toward the exit surface 36b. As the reflection part 34 and the reflection part 84, a highly reflective member, for example, a film made of a metal member is used.

  As illustrated in FIG. 7, a region 424 in which no phosphor is provided is provided between the pair of structures 32 </ b> R and 32 </ b> G and the other pair of structures 32 </ b> R and 32 </ b> G. The pair of structures 32 </ b> R, the structures 32 </ b> G, and the regions 424 where the phosphors are not provided are alternately provided in the circumferential direction of a circle centering on the rotation axis R of the wheel substrate 31. The excitation light 60 can pass through the region 424 where no phosphor is provided. Therefore, with the rotation of the wheel substrate 31, the wheel substrate 31 emits light in which blue excitation light and red fluorescence are mixed, light in which blue excitation light and green fluorescence are mixed, and blue excitation. Light is emitted sequentially.

Next, a projector 600 using the phosphor wheel 400 will be described with reference to FIG. Explanation of members common to the projector 1 according to the first embodiment is omitted.
The light source device 610 includes a laser diode array 2, a condenser lens 4, a phosphor wheel 400, a filter 620, and a pickup lens 6.

  As shown in FIG. 10, the filter 620 reflects the excitation light 60 incident from the phosphor wheel 400 side and transmits the red fluorescence and the green fluorescence emitted from the phosphor wheel 400. Are provided. Further, a region 624 where the dichroic film 622 is not provided is provided between two adjacent dichroic films 622. The region 624 where the dichroic film 622 is not provided and the region where the dichroic film 622 is provided are alternately provided in the circumferential direction of a circle around the rotation axis R of the filter 620. The excitation light 60 can pass through the region 624 where the dichroic film 622 is not provided. Further, the region 624 where the dichroic film 622 is not provided is subjected to a process for diffusing the excitation light 60. For example, in the region 624 where the dichroic film 622 is not provided, the excitation light 60 can be diffused by making the surface of the filter 620 rough.

  The filter 620 is also provided with an opening 633 through which the columnar wheel motor 33 passes. In the filter 620 and the phosphor wheel 400, the dichroic film 622 provided on the filter 620 overlaps the pair of structures 32R and 32G provided on the phosphor wheel 400 in plan view, and the dichroic film of the filter 620 The wheel motor 33 is mounted so that the region 624 where the 622 is not provided overlaps with the region 424 where the phosphor of the phosphor wheel 400 is not provided in plan view. By attaching the filter 620 and the phosphor wheel 400 to the wheel motor 33 as described above, red light, blue light, and green light are emitted from the light source device 610 as illumination light as the filter 620 and the phosphor wheel 400 rotate. Are fired sequentially.

  The illumination light emitted from the light source device 610 passes through other members and enters the mirror device 630. As the mirror device 630, for example, a DMD (digital micromirror device) element manufactured by Texas Instruments Inc. can be used. Each color light incident on the mirror device 630 as illumination light is modulated by the mirror device 630. The modulated light enters the prism 650, is reflected by the mirror surface in the prism 650, and enters the reflecting plate 651. The light incident on the reflection plate 651 is reflected toward the projection optical system 24. The light reflected in the direction of the projection optical system 24 is enlarged and projected on a screen (not shown) by the projection optical system 24. In this way, a red image, a blue image, and a green image are sequentially projected on the screen, and a color image is displayed.

  The phosphor wheel 400 limits the light emitting region in both the circumferential direction and the radial direction by providing the reflective portion 34 having a tapered shape in the circumferential direction and providing the reflective portion 84 having a tapered shape in the radial direction. , The increase in the light emitting area can be suppressed. Furthermore, the light ray angle with respect to the normal line of the exit surface 36b can be reduced on the exit surface 36b. Thereby, the light utilization efficiency as the whole system of the projector 600 including the phosphor wheel 400 can be further increased.

[Example 3]
FIG. 11 is a cross-sectional view of a main part of a phosphor wheel 700 that functions as a wavelength conversion element according to Example 3 of the invention. Differences from the phosphor wheel 100 according to the first embodiment will be described. In the phosphor wheel 700 according to the present embodiment, the reflection layer 72 that reflects the excitation light 60 and the fluorescence is formed on the dichroic film 38 at a position corresponding to the incident surface 36a of the phosphor layer 36 in the structure 32 of the first embodiment. It is provided instead.

  The excitation light 60 is irradiated to the phosphor 1000 (not shown) from the side where the structure 32 of the wheel substrate 31 is provided, and the phosphor 1000 emits fluorescence. Therefore, in the present embodiment, the fluorescence emission surface 36b of the phosphor layer 36 is also an excitation light incident surface. The fluorescence that has traveled toward the wheel substrate 31 in the phosphor layer 36 is reflected by the reflective layer 72. Therefore, the fluorescence emitted from the phosphor 1000 can be efficiently emitted from the emission surface 36b of the phosphor layer 36 without leaking to the wheel substrate 31 side. Similarly, the excitation light 60 traveling inside the phosphor layer 36 toward the wheel substrate 31 is similarly reflected by the reflection layer 72 and can be efficiently emitted from the emission surface 36 b of the phosphor layer 36.

  FIG. 12 shows a light source device 710 using a phosphor wheel 700. The excitation light 60 is applied to the phosphor 1000 from the side of the wheel substrate 31 where the structure 32 is provided, and a part of the excitation light 60 and the fluorescence emitted by the phosphor 1000 are captured by the pickup lens 6. The The light captured by the pickup lens 6 proceeds to the collimating optical system 11 described in the first embodiment. In this way, the light source device 710 is used as a light source for the projector. Even with such a reflective wheel substrate 31, as in the transmissive wheel substrate 31 described in the first embodiment, the effect of improving the light utilization efficiency of the entire system can be obtained.

  In the case of the reflective phosphor wheel 700, it is not necessary to use a transparent member as the wheel substrate 31. If a metal is used as the wheel substrate 31, heat generated in the phosphor 1000 can be effectively dissipated. In this case, as shown in Example 1 and Modification 1, it is preferable to provide the phosphor layer 36 in the groove provided on the surface of the wheel substrate. According to this configuration, the heat generated in the phosphor 1000 can be dissipated more efficiently. Further, if a metal having a high light reflectance such as aluminum is used, the wheel substrate itself functions as the reflecting portion 34, the reflecting portion 84, and the reflecting layer 72, so that it is not necessary to provide the reflecting portion 34 and the reflecting layer 72 separately.

[Example 4]
FIG. 13 is a schematic configuration diagram of a projector according to a fourth embodiment of the invention.
In Examples 1 to 3 described above, an example in which the phosphor wheel 100 that can be rotated by a motor is used as the wavelength conversion element has been described. On the other hand, in the projector 800 of this embodiment, a phosphor substrate 811 is used as a wavelength conversion element used in the light source device 810. The phosphor substrate 811 has a substrate body 812 and a structure 32F.

  As shown in FIG. 13, the substrate body 812 is a plate-like member and is made of a transparent member such as glass. The structure 32F has the same configuration as the structure 32R or 32G described in the second embodiment. In other words, the structure 32F includes a phosphor layer, a first reflection unit, a second reflection unit, a third reflection unit, and a fourth reflection unit. In order to efficiently use the excitation light, it is preferable that the spot of the excitation light formed on the phosphor substrate 811 does not protrude from the incident surface 36 a of the phosphor layer 36. Furthermore, it is more preferable that the area of the incident surface 36a of the phosphor layer 36 is the same as the area of the excitation light spot. A concave portion is provided on one surface of the substrate main body 812, that is, the surface of the substrate main body 812 opposite to the surface on which the excitation light 60 is incident, and the structure 32F is provided inside the concave portion. The phosphor substrate 811 of the present embodiment is fixed and does not rotate like the phosphor wheels of the first to third embodiments.

  Also in the projector 800 of the present embodiment, as in the first to third embodiments, the reflection portion is provided on the side surface of the phosphor layer so that the light traveling inside the phosphor layer is emitted from the emission surface of the phosphor layer. Easier to inject into the air. As a result, the light utilization efficiency of the entire projector system including the phosphor substrate can be improved.

  The phosphor wheel 31 of each embodiment is not limited to being applied to the projector 1 that uses a transmissive liquid crystal panel as a spatial light modulator or the projector 600 that uses a mirror device as a spatial light modulator. The phosphor wheel may be applied to a projector including a reflective LCOS (Liquid Crystal On Silicon).

[Example 5]
FIG. 14 is a schematic configuration diagram of a projector 820 according to the fifth embodiment of the invention.
The basic configuration of the projector 820 of the present embodiment is the same as that of the projector of the first embodiment, and only the configuration of the phosphor wheel is different. Therefore, in FIG. 14, the same reference numerals are given to the components common to FIG.
The light source device 821 emits illumination light including red (R) light, green (G) light, and blue (B) light. The light source device 821 includes a laser diode array 2, a condenser lens 4, a phosphor wheel 822 that functions as a wavelength conversion element, and a pickup lens 6.

  The laser diode array 2 is composed of a plurality of laser diodes 3 arranged in an array. The laser diode array 2 functions as a pumping light source unit that emits the pumping light 60.

  The excitation light 60 is, for example, B light having a wavelength near 450 nm. The condensing lens 4 functions as a condensing optical system that condenses the excitation light 60 emitted from the laser diode array 2 by the phosphor wheel 822. The phosphor wheel 822 emits fluorescence having a wavelength different from that of the excitation light 60 when irradiated with the excitation light 60. The pickup lens 6 is provided on the optical path of the excitation light 60. The pickup lens 6 captures the fluorescence emitted from the phosphor wheel 822 and the excitation light 60 transmitted through the phosphor wheel 822 and advances it to the collimating optical system 11.

  The collimating optical system 11 condenses the light from the light source device 821 on the rod integrator 12. The rod integrator 12 multi-reflects incident light to make it uniform. The superimposing lens 13 superimposes the light beam divided into a plurality by the rod integrator 12 using a spatial light modulator.

  The first dichroic mirror 14 reflects R light and G light incident from the superimposing lens 13 and transmits B light. The B light transmitted through the first dichroic mirror 14 has its optical path bent by reflection by the reflection mirror 16 and is incident on the incident-side polarizing plate 20B. The light transmitted through the incident side polarizing plate 20B enters the liquid crystal panel 21B. The liquid crystal panel 21B constitutes a spatial light modulation device that modulates the B light according to the image signal. The light transmitted through the liquid crystal panel 21B is incident on the exit-side polarizing plate 22B. The light transmitted through the exit-side polarizing plate 22B enters the cross dichroic prism 23.

  The R light and G light reflected by the first dichroic mirror 14 enter the second dichroic mirror 15. The second dichroic mirror 15 reflects G light and transmits R light. The G light whose optical path is bent by the reflection at the second dichroic mirror 15 enters the incident-side polarizing plate 20G. The G light transmitted through the incident side polarizing plate 20G is incident on the liquid crystal panel 21G. The liquid crystal panel 21G constitutes a spatial light modulation device that modulates G light according to an image signal. The light transmitted through the liquid crystal panel 21G is incident on the exit-side polarizing plate 22G. The light transmitted through the exit side polarizing plate 22G enters the cross dichroic prism 23.

  The R light that has passed through the second dichroic mirror 15 has its optical path bent by reflection by the reflection mirror 17 and enters the relay lens 18. The R light that has passed through the relay lens 18 has its optical path bent due to reflection by the reflection mirror 19, and is incident on the incident-side polarizing plate 20R. The R light transmitted through the incident side polarizing plate 20R enters the liquid crystal panel 21R. The liquid crystal panel 21R constitutes a spatial light modulation device that modulates R light according to an image signal. The light transmitted through the liquid crystal panel 21R is incident on the exit-side polarizing plate 22R. The light transmitted through the exit-side polarizing plate 22R enters the cross dichroic prism 23.

  The cross dichroic prism 23 that is a color combining optical system combines the light modulated by each spatial light modulation device into image light, and advances it to the projection optical system 24. The projection optical system 24 projects the image light combined by the cross dichroic prism 23 onto a screen (not shown).

  FIG. 15A is a plan view of a phosphor wheel 822 that functions as a wavelength conversion element, and FIG. 15B is a cross-sectional view of the phosphor wheel 822. 15A and 15B, the wheel motor 33 is mounted on the phosphor wheel 822. In FIG. 15B, the pickup lens 6 is further combined with the phosphor wheel 822. . The phosphor wheel 822 includes a structure 823 and a wheel substrate 31 that can rotate around the rotation axis R. The structure 823 will be described in detail later. The plan view of the phosphor wheel 822 shown in FIG. 15A is a plan view of the phosphor wheel 822 viewed from the side where the structure 823 is provided. Further, the cross-sectional view of the phosphor wheel 822 shown in FIG. 15B is a cross section including the center position of the phosphor wheel 822. FIG. 16 is a cross-sectional view A-A ′ of the phosphor wheel 822 along the radial direction of a circle centered on the rotation axis R of the wheel substrate 31.

  As shown in FIGS. 15A and 15B, the wheel substrate 31 is a circular plate-like member, and is made of a transparent member such as glass. In the center of the wheel substrate 31, an opening through which the cylindrical wheel motor 33 passes is provided. The wheel substrate 31 is integrated with the wheel motor 33 by mounting the wheel substrate 31 to the wheel motor 33 in the opening. The wheel substrate 31 rotates with the center position of the circular shape as the rotation axis R by driving the wheel motor 33.

  As shown in FIG. 16, in this embodiment, the structure 823 includes a light emitting element 824, a first reflecting portion 34a, and a second reflecting portion 34b. The light emitting element 824 includes a phosphor layer 36 including a plurality of particulate phosphors 1000 and a light transmission layer 825. The phosphor 1000 is excited by irradiation with the excitation light 60 and generates fluorescence. The phosphor layer 36 includes a binder made of a transparent resin in which particles of the phosphor 1000 are dispersed. The light transmission layer 825 is provided on the opposite side of the phosphor layer 36 from the wheel substrate 31 and transmits light incident from the phosphor layer 36.

  The structure 823 is provided on the surface 31a opposite to the side on which the excitation light 60 is incident among the plurality of surfaces of the wheel substrate 31. As shown in FIG. 15A, the light emitting element 824 included in the structure 823 forms a ring having a certain width in a plan view. The ring formed by the light emitting element 824 corresponds to the spot trajectory of the excitation light 60 obtained by rotating the wheel substrate 31.

  The phosphor wheel 822 can dissipate the heat generated in the phosphor 1000 to the outside effectively by providing the structure 823 on the surface of the wheel substrate 31.

  As shown in FIG. 16, the light emitting element 824 includes a first side surface 35 a and a second side surface 35 b having a circular shape centering on the rotation axis R of the wheel substrate 31 in plan view. The first side surface 35a and the second side surface 35b are opposed to each other. The first side surface 35 a is the side surface of the annular light emitting element 824 on the wheel motor 33 side, and the second side surface 35 b is the side surface of the annular light emitting element 824 on the outer edge side of the wheel substrate 31. In the present embodiment, the first side surface 35a and the second side surface 35b may be collectively referred to as the side surface 35 as appropriate.

  The first reflecting portion 34 a is provided on the first side surface 35 a of the light emitting element 824, and the second reflecting portion 34 b is provided on the second side surface 35 b of the light emitting element 824. In a cross section intersecting the first side surface 35a, for example, a cross section along the radial direction of a circle centering on the rotation axis R, the distance between the first side surface 35a and the second side surface 35b is from the phosphor layer 36. It increases toward the light transmission layer 825. Therefore, the distance between the first reflecting portion 34 a and the second reflecting portion 34 b is also increased from the phosphor layer 36 toward the light transmitting layer 825. In the present embodiment, the first reflecting portion 34a and the second reflecting portion 34b may be collectively referred to as the reflecting portion 34 as appropriate. In addition, in this specification, for convenience, the reflecting portion provided in the above-described form is referred to as a tapered reflecting portion. Or it says that the reflective part has a taper shape. The reflection unit 34 reflects the fluorescence and excitation light incident from the phosphor layer 36 and the fluorescence and excitation light incident from the light transmission layer 825. As the reflection part 34, a highly reflective member, for example, a film made of a metal member is used.

  The dichroic film 38 is provided between the wheel substrate 31 and the phosphor layer 36, that is, on the incident surface 36 a of the excitation light 60 among a plurality of surfaces of the phosphor layer 36. The dichroic film 38 functions as a wavelength separation layer having a wavelength characteristic that transmits the excitation light 60 emitted from the laser diode array 2 and reflects the fluorescence emitted from the phosphor 1000.

  The phosphor 1000 generates fluorescence including G light and R light when irradiated with the excitation light 60. A part of the excitation light 60 incident on the phosphor layer 36 is emitted from the phosphor layer 36 toward the pickup lens 6 together with the fluorescence. As described above, the light source device 821 emits white illumination light by mixing the fluorescence including the G light and the R light and the excitation light 60 including the B light. For example, a YAG phosphor is used as the phosphor. The phosphor layer 36 is obtained, for example, by applying a powdered phosphor 1000 and a binder to the wheel substrate 31 and thermally curing the mixture. The light transmission layer 825 is made of a transparent resin having the same refractive index as the binder of the phosphor layer 36.

  A spot of excitation light 60 is formed on the incident surface 36 a of the phosphor layer 36. In the light source device 821, the spot diameter d1 of the excitation light 60 measured in the radial direction of a circle centered on the rotation axis R is substantially equal to the radial width M of the incident surface 36a, or the radial width of the incident surface 36a. It is adjusted to be smaller than M. Thereby, the incident position of the excitation light 60, that is, the upper limit value of the shake due to the rotation of the phosphor wheel 822, which is allowed to prevent the excitation light spot formed on the wavelength conversion element from protruding from the incident surface 36a, is increased. Can do.

  The excitation light 60 incident on the wheel substrate 31 passes through the wheel substrate 31 and the dichroic film 38 and enters the phosphor layer 36. A part of the excitation light 60 incident on the phosphor layer 36 excites the phosphor 1000, and the excited phosphor 1000 emits fluorescence. The fluorescence generated in the phosphor 1000 is emitted approximately isotropic around the light emission position.

  Of the fluorescence and excitation light 60 that has traveled from the phosphor layer 36 to the light transmission layer 825, the component that has entered the interface between the light transmission layer 825 and air at an angle smaller than the critical angle is the fluorescence emission surface 825b of the light transmission layer 825. To the air.

  In this embodiment, since the refractive index of the light transmission layer 825 is the same as the refractive index of the binder of the phosphor layer 36, no light is reflected at the interface between the phosphor layer 36 and the light transmission layer 825. Therefore, the fluorescence emitted from the phosphor 1000 and the excitation light scattered by the phosphor 1000 are not reflected at the interface between the phosphor layer 36 and the light transmission layer 825 and returned to the phosphor layer 36. As a result, light loss and heat generation due to the absorption of the fluorescence by the phosphor layer 36 are suppressed. Note that the light transmission layer 825 is not limited to the case where the refractive index is the same as that of the binder.

  The fluorescence that has traveled toward the wheel substrate 31 inside the phosphor layer 36 is reflected by the dichroic film 38 and travels in the direction of the light transmission layer 825. Therefore, the fluorescence emitted from the phosphor 1000 does not leak to the wheel substrate 31 side and can be efficiently emitted from the fluorescence emission surface 825b of the light transmission layer 825. Hereinafter, in Embodiments 5 to 10, the fluorescence emission surface (exit surface) 825b is a plurality of surfaces of the light transmission layer 825, and the fluorescence emitted from the phosphor 1000 is emitted from the light transmission layer 825 into the air. Refers to the surface to be done.

  Further, the traveling direction of the light can be changed by the tapered reflecting portion 34 so that the light ray angle with respect to the normal line N of the wheel substrate 31 becomes small. Accordingly, the light ray angle at the fluorescence emission surface 825b of the light transmission layer 825 is reduced, and total reflection of light at the interface between the light transmission layer 825 and air is suppressed. As a result, the light traveling inside the light transmission layer 825 is transmitted. It becomes easy to inject into the air from the fluorescence emission surface 825b of the light transmission layer 825.

  Further, the fluorescent component that travels in the phosphor layer 36 parallel to the wheel substrate 31 is prevented from propagating in the radial direction of the phosphor wheel 822 due to reflection by the reflecting portion 34. In the phosphor wheel 822 according to the present embodiment, since the propagation of fluorescence in the phosphor layer 36 is blocked by the reflecting portion 34, an increase in the light emission area in the phosphor layer 36 is suppressed.

  Further, by reducing the emission angle of the light emitted from the fluorescence emission surface 825b of the light transmission layer 825, the amount of light taken in by the pickup lens 6 or the like can be increased. Thereby, the projector 820 including the phosphor wheel 822 can improve the light utilization efficiency of the entire system.

(Modification 1)
FIG. 17 is a cross-sectional view of a main part of the phosphor wheel 830 according to the first modification of the present embodiment. In the phosphor wheel 822 according to the fifth embodiment, the structure 823 is provided on the surface 31a opposite to the side on which the excitation light 60 is incident among the plurality of surfaces of the wheel substrate 31. The phosphor wheel 830 according to the present invention is characterized in that a structure body 823 is provided in a groove 832 provided in the surface 831a of the wheel substrate 831. The reflector 34 is sandwiched between the side surface 35 of the light emitting element 824 and the wall surface of the groove 832. The dichroic film 38 is provided on the bottom surface of the groove 832. By providing the phosphor layer 36 in the groove 832, the material of the phosphor layer 36 can be stably applied.

(Modification 2)
FIG. 18 is a plan view of a phosphor wheel 840 according to the second modification of the present embodiment. FIG. 19 is a cross-sectional view of a main part of the phosphor wheel 840. The phosphor wheel 840 according to this modification includes a heat conducting portion 841 that conducts heat from the phosphor 1000. The heat conducting portion 841 is provided on the surface 31 a of the wheel substrate 31 so as to be in contact with the structure 823. The heat conducting unit 841 is configured using a member having high thermal conductivity, such as copper or aluminum.

  The heat generated in the phosphor 1000 due to the irradiation of the excitation light 60 is conducted from the phosphor layer 36 through the reflecting portion 34 or from the phosphor layer 36 through the light transmitting layer 825 and the reflecting portion 34 to the heat conducting portion 841. . The phosphor wheel 840 can dissipate the heat generated in the phosphor 1000 effectively by providing the heat conducting portion 841. The phosphor wheel 840 can generate fluorescence with high efficiency by effective heat dissipation.

  The heat conducting portion 841 is not limited to the case where the portion of the surface of the wheel substrate 31 other than the structure 823 is completely covered. In order to effectively dissipate the heat generated in the phosphor 1000, the heat conducting portion 841 only needs to be provided on at least part of the periphery of the structure 823 in the surface 31a of the wheel substrate 31. . The phosphor wheel 840 may be configured such that a part of the heat conducting portion 841 functions as a reflecting portion in addition to providing the reflecting portion 34 between the side surface 35 of the light emitting element 824 and the heat conducting portion 841.

(Modification 3)
FIG. 20 is a cross-sectional view of a main part of a phosphor wheel 850 according to the third modification of the present embodiment. In the phosphor wheel 850 according to this modified example, a structure 823 is provided in a groove 832 formed in the wheel substrate 831 and the heat conducting unit 841. Also in the case of this modification, the phosphor wheel 850 can dissipate the heat generated in the phosphor 1000 effectively by providing the heat conducting portion 841. The heat conducting portion 841 may completely cover a portion of the surface of the wheel substrate 831 other than the groove 832, or may be provided on a part of the periphery of the structure 823.

(Modification 4)
FIG. 21 is a cross-sectional view of a main part of a phosphor wheel 860 according to Modification 4 of the present embodiment. The phosphor wheel 860 according to this modification has a concavo-convex structure (moth eye structure) 861 provided on the fluorescence emission surface 825 b of the light transmission layer 825.

  Each of the concavo-convex structures 861 is configured to have a width shorter than the wavelength of fluorescence, for example, and is provided two-dimensionally. The uneven structure 861 suppresses reflection of light at the interface between the light transmission layer 825 and air. The phosphor wheel 860 according to this modification can efficiently extract light from the light transmission layer 825 by the uneven structure 861.

(Modification 5)
In the phosphor wheel according to Example 5 and Modifications 1 to 4, the first reflecting portion 34a and the second reflecting portion 34b are provided, but only one of them may be provided. For example, when only the second reflecting portion 34b is provided, the fluorescent component that travels at a large angle with respect to the normal line N is reflected toward the outer side of the wheel substrate 31 by reflection at the second reflecting portion 34b. Propagation is prevented. The light reflected by the second reflecting portion 34 b travels while being scattered by the phosphor 1000 inside the phosphor layer 36 and enters the light transmission layer 825. Therefore, even when only one of the first reflecting portion 34a and the second reflecting portion 34b is provided, the effect of improving the light utilization efficiency of the entire system can be obtained.

[Example 6]
FIG. 22 is a plan view of a phosphor wheel 870 functioning as a wavelength conversion element according to Example 6 of the present invention. In the present embodiment, the reflecting portions are provided on the side surface provided in the shape of a circle centered on the rotation axis R of the wheel substrate 31 and the side surface provided in the radial direction of the circle. The phosphor wheel 870 is applied to the light source device 810 of the fifth embodiment. The same parts as those in the fifth embodiment are denoted by the same reference numerals, and redundant description is omitted. The structure including the phosphor layer is divided into a plurality of unit structures 871 by reflection portions arranged in the circumferential direction.

  FIG. 23 is a perspective view of one unit structure 871. The unit structure 871 includes a light emitting element 824, a first reflecting portion 34a, a second reflecting portion 34b provided in the circumferential direction, a third reflecting portion 84a provided in the radial direction, and a fourth reflecting portion. 84b is included. The light emitting element 824 includes a phosphor layer 36 including a particulate phosphor 1000 and a light transmission layer 825. Thus, the light emitting element 824 is surrounded by the first reflecting portion 34a, the second reflecting portion 34b, the third reflecting portion 84a, and the fourth reflecting portion 84b. The first reflecting portion 34a and the second reflecting portion 34b provided in the circumferential direction for one unit structure 871 are arranged in the radial direction of the circle in the same manner as the reflecting portion 34 (see FIG. 16) in the fifth embodiment. In the cross section along, it has a taper shape. In the present embodiment, the first reflecting portion 34a and the second reflecting portion 34b may be collectively referred to as the reflecting portion 34 as appropriate. Similarly, the third reflecting portion 84a and the fourth reflecting portion 84b may be collectively referred to as the reflecting portion 84.

  24 is a cross-sectional view of the main part of the phosphor wheel 870 in the circumferential direction indicated by the alternate long and short dash line in FIG. The plurality of unit structures 871 are partitioned from each other by the reflecting portion 84 and are arranged in the circumferential direction. The dichroic film 38 that is a wavelength separation layer is provided between the wheel substrate 31 and the phosphor layer 36 of each unit structure 871. The reflecting portion 84 provided in the radial direction with respect to one unit structure 871 has a tapered shape in a cross section along the circumferential direction.

  In the phosphor wheel 870 according to the present embodiment, the reflective portion 34 having a tapered shape is provided in the circumferential direction, and the reflective portion 84 having a tapered shape is provided in the radial direction. Limited. Therefore, it is possible to suppress an increase in the light emitting area and reduce the light beam angle on the fluorescence emission surface 825b of the light transmission layer 825. Thereby, the projector including the phosphor wheel 870 can further improve the light utilization efficiency of the entire system.

  As shown in FIG. 24, there is a region where the phosphor 1000 is not provided between two adjacent unit structures 871. Therefore, the laser diode array 2 (see FIG. 14) does not irradiate the excitation light 60 to a region where the phosphor 1000 is not provided, that is, the excitation light 60 is appropriately applied to the phosphor layer 36 of each unit structure 871. The excitation light 60 is emitted at a pulse frequency corresponding to the rotation of the phosphor wheel 870 so as to be incident. The light source device 821 can improve the light utilization efficiency by stopping the emission of the excitation light 60 to the region where the phosphor 1000 is not provided, and can stabilize the intensity of the light emitted from the light source device 821. it can. Furthermore, the lifetime of the laser diode 3 can be extended by using pulsed light emission.

When one pulse of the excitation light 60 is incident on the phosphor wheel 870, the length L of the irradiation region in the circumferential direction is calculated by Equation (1).
L = d2 + 2πrmD / F (1)

  However, d2 is the spot diameter (unit m) in the circumferential direction of the excitation light 60, r is the distance (unit m) between the radial center of the light emitting element 824 and the rotation center R, and m is the phosphor wheel 870. The rotation speed (unit: rps), D is the duty ratio of the pulse of the excitation light 60, and F is the pulse frequency (unit: Hz) of the excitation light 60. As shown in FIG. 23, by setting the length of the incident surface 36a of the phosphor layer 36 in the circumferential direction to L, it is possible to appropriately irradiate the unit structure 51 with the excitation light 200.

When the length L is allowable up to T times the spot diameter d2, in other words, the amount of bleeding of the excitation light 60 is allowable up to T times the spot diameter d2, T = L / d2 is substituted into the equation (1). Thus, equation (2) for the distance r is obtained.
r = (T−1) d2F / (2πrmD) (2)

  For example, when the pulse frequency F is 100 kHz, the duty ratio D is 0.3, the spot diameter d2 is 1 mm, the rotational speed m is 10,000 / 60 rps (= 10000 rpm), and T is 1.1, The distance r is calculated to be approximately 3.2 cm. At this time, the length in the circumferential direction of one unit structure 871 is approximately 1.1 mm. The light source device 821 synchronizes the irradiation of the excitation light 60 by the laser diode array 2 and the rotation of the phosphor wheel 870 by design and driving according to such calculation.

  The number S of unit structures 871 formed on the phosphor wheel 870 is obtained by S = F / m. Since S is an integer, F is an integral multiple of m. Thereby, the laser diode array 2 can appropriately make the excitation light 60 incident on the light emitting element 824 of each unit structure 871 avoiding the region where the phosphor 1000 is not provided.

  The phosphor wheel of each embodiment is not limited to being applied to the projector 1 that uses a transmissive liquid crystal panel as a spatial light modulator. The phosphor wheel may be applied to a projector equipped with a reflective LCOS (Liquid Crystal On Silicon) or DMD (Digital Micromirror Device).

[Example 7]
FIG. 25 is a cross-sectional view of a main part of a phosphor wheel 880 that functions as a wavelength conversion element according to Example 7 of the invention. Differences from the phosphor wheel 822 according to the fifth embodiment will be described. In the phosphor wheel 880 according to the present embodiment, the reflection layer 72 that reflects the excitation light 60 and the fluorescence is formed on the dichroic film 38 at a position corresponding to the incident surface 36a of the phosphor layer 36 in the structure 823 of the fifth embodiment. It is provided instead. The excitation light 60 is applied to the phosphor 1000 from the side of the wheel substrate 31 on which the structure 823 is provided. Therefore, in the present embodiment, the fluorescence emission surface 825 b of the light transmission layer 825 is also an entrance surface of excitation light to the phosphor layer 36.

  The fluorescence that has traveled toward the wheel substrate 31 inside the phosphor layer 36 is reflected by the reflection layer 72 and travels in the direction of the light transmission layer 825. Therefore, the fluorescence emitted from the phosphor 1000 does not leak to the wheel substrate 31 side and can be efficiently emitted from the fluorescence emission surface 825b of the light transmission layer 825. Similarly, the excitation light traveling inside the phosphor layer 36 toward the wheel substrate 31 is also reflected by the reflection layer 72 and can be efficiently emitted from the fluorescence emission surface 825 b of the light transmission layer 825.

  FIG. 26 shows an example of a light source device 881 using a phosphor wheel 880. The excitation light 60 is applied to the phosphor 1000 from the side where the structure 823 of the wheel substrate 31 is provided, and a part of the excitation light 60 and the fluorescence emitted by the phosphor 1000 are captured by the pickup lens 6. . The light captured by the pickup lens 6 proceeds to the collimating optical system 11 described in the fifth embodiment. In this way, the light source device 881 is used as a light source of the projector. Even in the case of such a reflective wheel substrate, the effect of improving the light utilization efficiency of the entire system can be obtained, similar to the transmissive wheel substrate described in the fifth embodiment.

  In the case of the reflective phosphor wheel 880, it is not necessary to use a transparent member as the wheel substrate 31. If a metal is used as the wheel substrate, the heat generated in the phosphor 1000 can be effectively dissipated. In this case, as shown in the first modification of the fifth embodiment, it is preferable to provide the light emitting element 824 in the groove 832 provided on the surface of the wheel substrate 831. According to this configuration, the heat generated in the phosphor 1000 can be dissipated more efficiently. Furthermore, if a metal having a high light reflectance such as aluminum is used, the wheel substrate itself functions as a reflecting member, so that it is not necessary to provide the reflecting portion 34 and the reflecting layer 72.

[Example 8]
FIG. 27 is a schematic configuration diagram of a projector 890 according to the eighth embodiment of the invention.
In Examples 5 to 7, the example in which the phosphor wheel that is rotatable by the wheel motor 33 is used as the wavelength conversion element has been described. On the other hand, in the projector 890 of this embodiment, a phosphor substrate 891 is used as a wavelength conversion element used for the light source device 893. The phosphor substrate 891 includes a substrate body 892 and a structure 823.

As shown in FIG. 27, the substrate body 892 is a plate-like member and is made of a transparent member such as glass. In this embodiment, the structure 823F has the same structure as the structure 871 described in Embodiment 6. That is, the unit structure 871 includes the light emitting element 824, the first reflecting portion 34a provided in the circumferential direction, the second reflecting portion 34b, the third reflecting portion 84a provided in the radial direction, and the fourth reflecting portion. The reflection part 84b is included. In order to efficiently use the excitation light, it is preferable that the spot of the excitation light formed on the phosphor substrate 891 does not protrude from the incident surface 36 a of the phosphor layer 36. Furthermore, the area of the incident surface 36a of the phosphor layer 36 is preferably the same as the area of the excitation light spot.
A structure body 823 is provided on one surface of the substrate main body 892, that is, the surface of the substrate main body 892 opposite to the surface on which the excitation light 60 is incident. The phosphor substrate 891 of the present embodiment is fixed and does not rotate like the phosphor wheels of the fifth to seventh embodiments.

  Also in the projector 890 of this embodiment, similarly to the above-described Embodiments 5 to 7, light traveling inside the phosphor layer is easily emitted into the air from the emission surface of the phosphor layer. As a result, the light utilization efficiency of the entire projector system including the phosphor substrate can be improved.

[Example 9]
FIG. 28 is a schematic configuration diagram of a projector 900 according to Embodiment 9 of the present invention.
In the projector 900 of the present embodiment, the configuration subsequent to the collimating optical system 11 is the same as that of the projector of the first embodiment. Unlike the projector of the first embodiment, the projector 900 of the present embodiment differs from the projector of the first embodiment in the configuration of the light source device 901 upstream of the collimating optical system 11 and includes a correction unit 902 that corrects the positional deviation of the incident surface of the excitation light to the light emitting element 824. I have. Furthermore, the incident surface of the excitation light to the light emitting element 824 is the end of the first reflecting portion 34a opposite to the wheel substrate 31 and the opposite side of the second reflecting portion 34b from the wheel substrate 31. It is a region between the end portions. Hereinafter, the incident surface of the excitation light to the light emitting element 824 is simply referred to as the incident surface of the light emitting element 824.
28, the same reference numerals are given to the same components as those in FIG. 1 of the first embodiment, and detailed description thereof will be omitted.

  As shown in FIG. 28, the light source device 901 of the present embodiment includes an ultraviolet laser diode 903, a phosphor wheel 904, a blue laser diode 905, a cross dichroic prism 906, a dichroic mirror 907, a correction unit 902, It is mainly equipped with. The ultraviolet laser diode 903 functions as a light source unit for excitation light that emits ultraviolet light that is excitation light. The phosphor wheel 904 functions as a wavelength conversion element that rotates by the wheel motor 33 and emits fluorescence when irradiated with excitation light. The correction unit 902 corrects the positional deviation of the incident surface of the light emitting element 824 caused by the rotation of the phosphor wheel 904. The configuration and function of the correction unit 902 will be described in detail later.

  The phosphor wheel 904 includes a wheel substrate 908 and a structure 823 provided in a groove formed on one main surface of the wheel substrate 908. As in the fifth embodiment, the structure 823 includes the phosphor layer 36 and the reflection portion, and the light-emitting element 824 includes the phosphor layer 36 and the light transmission layer 825. Since the structure of the structure 823 has been described in the fifth embodiment, a detailed description of the structure 823 is omitted. In the present embodiment, similarly to the phosphor wheel 880 according to the seventh embodiment, the excitation light is applied to the phosphor 1000 from the side of the wheel substrate 908 where the structure 823 is provided. Therefore, in this embodiment, the fluorescence emission surface 825 b of the light transmission layer 825 corresponds to the incident surface of the light emitting element 824. The wheel substrate 908 of this embodiment is a circular plate-like member and is made of a metal material such as aluminum. A rotation axis R is provided at the center of the wheel substrate 908, and the rotation axis R is connected to the wheel motor 33. The wheel substrate 908 rotates around the rotation axis R at a speed of, for example, 7200 rotations by driving the wheel motor 33. The phosphor wheel 904 is rotatable around a rotation axis R that intersects one surface of the wheel substrate 908. Therefore, it can be said that the spot of the excitation light formed on the phosphor wheel 904 moves on the phosphor wheel 904 in time. The phosphor layer 36 is provided on one surface of the wheel substrate 908 along a circle centered on the rotation axis R.

In this embodiment, the wheel substrate 908 is made of, for example, an aluminum disc having a diameter of 40 mm, and the inner surface has, for example, an inner diameter of 37 mm, an outer diameter of 38.3 mm, and a width (a dimension in the radial direction of the wheel substrate 908). ) Is 1.3 mm and the depth is 0.15 mm. That is, the width of the fluorescence emission surface 825b of the structure 823 is 1.3 mm. In addition, the width of the bottom surface of the structure 823 corresponding to the incident surface 36a of the excitation light in the phosphor wheel 880 according to Example 7 is 1 mm. Further, in order to facilitate correction of a positional shift described later, the inclination angle of the first side surface 35a with respect to one main surface of the wheel substrate 908 is set to the inclination angle of the wheel substrate 908 in the cross section of the structure 823 in the radial direction of the wheel substrate 908. It is preferable to make it equal to the inclination angle of the second side surface 35b with respect to one main surface.
A silver film is formed on the inner surface of the groove as a reflective film. A protective film made of silicon oxide is formed on the surface of the silver film. For example, a silicone resin in which phosphor particles that are excited by ultraviolet light having a wavelength of 405 nm and emit yellow light having a wavelength of 500 to 700 nm are dispersed and included is embedded in the groove. The phosphor layer 36 is composed of a silicone resin in which a large number of phosphor particles are dispersed and encapsulated. By forming a silver film on the inner surface of the groove, yellow light emitted from the phosphor layer 36 is efficiently extracted from the phosphor wheel 904.

  The ultraviolet laser diode 903 emits, for example, ultraviolet light having a wavelength of 405 nm as excitation light for exciting the phosphor layer 36. The ultraviolet light emitted from the ultraviolet laser diode 903 is collimated by the first collimator lens 909, and the beam is shaped by a computer generated hologram 910 (CGH: Computer Generated Hologram, hereinafter referred to as CGH), and then the cross dichroic prism. Incident at 906. An optical axis of light emitted from the ultraviolet laser diode 903 and passing through the first collimator lens 909, CGH 910, and cross dichroic prism 906 is referred to as an optical axis LA.

  The cross dichroic prism 906 reflects a light having a wavelength of less than 500 nm, transmits a light having a wavelength of 500 nm or more, and reflects a light having a wavelength of 700 nm or more and transmits light having a wavelength of less than 700 nm. 2 wavelength separation films 912. The ultraviolet light incident on the cross dichroic prism 906 is reflected by the first wavelength separation film 911, bends the optical axis by 90 degrees, and travels toward the phosphor wheel 904. The optical axis of ultraviolet light (excitation light) reflected by the first wavelength separation film 911 and bent by 90 degrees is referred to as an optical axis LC.

  A pickup lens 913 is provided between the cross dichroic prism 906 and the phosphor wheel 904. The ultraviolet light emitted from the ultraviolet laser diode 903 passes through the first collimator lens 909, the CGH 910, and the pickup lens 913 and is collected on the phosphor layer 36 of the phosphor wheel 904. At this time, the position of the pickup lens 913 on the optical axis LC is optimized by a second actuator described later, so that the ultraviolet light is a 1.2 mm square spot (light source image) on the wheel substrate 908. Is imaged. The size of the ultraviolet light spot is 1.2 mm square, and one side of the rectangular spot substantially coincides with the radial direction of the wheel substrate 908. That is, the spot size W1 in the cross section in the radial direction of the wheel substrate 908 is 1.2 mm. The width W2 of the incident surface of the light emitting element 824 in the radial cross section of the wheel substrate 908 is 1.3 mm. Therefore, when the excitation light condensing position and the phosphor layer 36 are in an appropriate positional relationship, the excitation light condensing position is located on the incident surface of the light emitting element 824, that is, on the fluorescence emitting surface 825 b of the light transmitting layer 825. In addition, the spot of excitation light formed on the wheel substrate 908 does not protrude outside the incident surface of the light emitting element 824. In this embodiment, the spot size W1 is slightly smaller than the width W2 of the incident surface of the light emitting element 824. However, in order to effectively use both the phosphor layer 36 and the excitation light, the spot size W1 is set to It is preferable to make the width W 2 of the incident surface of the light emitting element 824 equal.

  When ultraviolet light enters the phosphor layer 36, the phosphor is excited by the ultraviolet light and emits yellow light having a wavelength of 500 to 700 nm. Yellow light emitted from the phosphor enters the cross dichroic prism 906 through the pickup lens 913, passes through the first wavelength separation film 911 and the second wavelength separation film 912, and enters the subsequent collimating optical system 11. Head. On the other hand, on the optical axis LA, a dichroic mirror 907 that reflects light having a wavelength of less than 500 nm and transmits light having a wavelength of 500 nm or more on the side opposite to the side where the ultraviolet laser diode 903 is provided across the cross dichroic prism 906. Is provided.

  If the optical axis that passes through the dichroic mirror 907 and is orthogonal to the optical axis LA is the optical axis LB, a blue laser diode 905 that emits blue light having a wavelength of 460 nm, for example, is provided on the optical axis LB. A second collimator lens 914 is provided between the dichroic mirror 907 and the blue laser diode 905. The blue light emitted from the blue laser diode 905 is collimated by the second collimator lens 914 and then enters the dichroic mirror 907. The blue light is reflected by the dichroic mirror 907 and enters the dichroic prism 906. The blue light incident on the dichroic prism 906 is reflected by the first wavelength separation film 911 and travels to the subsequent collimating optical system 11. In this way, the yellow light emitted from the phosphor layer 36 and the blue light emitted from the blue laser diode 905 are combined to become white light, and the white light enters the collimating optical system 11.

  The correction unit 902 includes a first actuator 915, a second actuator 916, an infrared laser diode 917, a diffraction grating 918, a photodetector 919, a cylindrical lens 920, a polarization beam splitter 921 (Polarized Beam Splitter). , Hereinafter abbreviated as PBS), a quarter-wave plate 922, a third collimator lens 923, and a controller 924. A first actuator 915 is installed on the wheel motor 33 of the phosphor wheel 904. The first actuator 915 corresponds to a first correction unit that corrects the positional deviation of the incident surface of the light emitting element 824 in the direction perpendicular to the optical axis LC direction of the excitation light. This correction is equivalent to correcting the relative positional relationship between the phosphor layer 36 and the spot of the excitation light. By driving the first actuator 915, the phosphor wheel 904 is translated in a direction parallel to the main surface of the wheel substrate 908. The pickup lens 913 is provided with a second actuator 916. The second actuator 916 corresponds to a second correction unit that corrects the positional deviation of the incident surface of the light emitting element 824 in the optical axis LC direction of the excitation light. This correction is equivalent to correcting the spot size of the excitation light when the excitation light is not parallel light. By driving the second actuator 916, the pickup lens 913 is translated in a direction parallel to the optical axis LC.

  On the optical axis LA, on the side opposite to the side where the dichroic prism 906 is provided across the dichroic mirror 907, the quarter wavelength plate 922, the third collimator lens 923, the PBS 921, diffraction, in order from the dichroic mirror 907 side. A grating 918 and an infrared laser diode 917 are arranged. The PBS 921 is arranged so that the transmission axis of the PBS 921 coincides with the polarization axis of the infrared light emitted from the infrared laser diode 917. A quarter-wave plate 922, a third collimator lens 923, a PBS 921, a diffraction grating 918, and an infrared laser diode 917 disposed on the rear stage side of the dichroic mirror 907 detect the amount of positional deviation of the incident surface of the light emitting element 824. Functions as a detection unit.

  The infrared laser diode 917 emits infrared light having a wavelength of, for example, 780 nm as detection light for detecting whether or not the incident surfaces of the pickup lens 913 and the light emitting element 824 are at appropriate positions. The infrared light emitted from the infrared laser diode 917 is divided into three beams by the diffraction grating 918, and then sequentially passes through the PBS 921, the third collimator lens 923, the quarter wavelength plate 922, and the dichroic mirror 907. , Enters the cross dichroic prism 906. Infrared light incident on the cross dichroic prism 906 is reflected by the second wavelength separation film 912, enters the phosphor wheel 904 through the pickup lens 913, and is reflected by the phosphor wheel 904.

  The infrared light reflected by the phosphor wheel 904 passes through the pickup lens 913 and is reflected by the second wavelength separation film 912 of the cross dichroic prism 906, and is then dichroic mirror 907, quarter wavelength plate 922, and third collimator. The light passes through the lens 923 in order and enters the PBS 921. At this time, since the infrared light is transmitted through the quarter-wave plate 922 twice in the forward path and the return path, the polarization axis of the infrared light incident on the PBS 921 is the infrared light immediately after being emitted from the infrared laser diode 917. It is in a state rotated by 90 ° with respect to the polarization axis. Therefore, the infrared light is reflected by the PBS 921 and enters the photodetector 919 via the cylindrical lens 920.

  The photodetector 919 detects a position shift of the incident surface of the light emitting element 824 from a proper position in a direction parallel to the optical axis LC, that is, a so-called focus shift, based on the incident infrared light. The photodetector 919 further detects a positional deviation of the incident surface of the light emitting element 824 from a proper position in a direction perpendicular to the optical axis LC, a so-called tracking deviation. Here, the appropriate position of the incident surface of the light emitting element 824 in the direction parallel to the optical axis LC can be, for example, a condensing point of excitation light. Further, the appropriate position of the incident surface of the light emitting element 824 in the direction perpendicular to the optical axis LC means that the spot of ultraviolet light (excitation light) does not protrude outside the incident surface of the excitation light to the phosphor layer 36. It is a position. For detecting the focus shift, the red color after passing through the cylindrical lens 920 is determined depending on whether the pickup lens 913 is in the best focus state, formed before or after the best focus. It utilizes the fact that the beam shape of external light changes. That is, a known astigmatism method is used to detect the focus shift. The tracking deviation is detected by using the main beam and the two sub beams, and the fact that the difference in the amount of light between the two sub beams changes depending on the direction of the tracking deviation. That is, a known three-beam method is used to detect tracking deviation. Note that the detection method of focus deviation and tracking deviation is not limited to the above method. For example, the Foucault method may be used to detect a focus shift, or the push-pull method may be used to detect a tracking shift.

  An output signal of the photodetector 919 is sent to the control unit 924. Based on the output signal of the photodetector 919, the control unit 924 sends a drive signal for moving the pickup lens 913 in a direction parallel to the optical axis LC in accordance with the direction and amount of focus deviation. Send to. In addition, the control unit 924 outputs a drive signal for moving the phosphor wheel 904 in a direction perpendicular to the optical axis LC in accordance with the direction and amount of tracking deviation based on the output signal of the photodetector 919. To the actuator 915. The second actuator 916 drives the pickup lens 913 in a direction parallel to the optical axis LC so that the light collected by the pickup lens 913 is always focused on the incident surface of the light emitting element 824 with the best focus. This correction corresponds to correcting that the spot size fluctuates due to a focus shift. Accordingly, it is possible to reduce the fact that the spot protrudes from the incident surface of the light emitting element 824 due to the increase of the spot due to the focus shift, and the use efficiency of the excitation light is reduced. Moreover, the fluctuation | variation of the intensity | strength of the light inject | emitted from a light source device can be made small. The first actuator 915 moves the phosphor wheel 904 in a direction perpendicular to the optical axis LC so that the light condensed by the pickup lens 913, that is, the spot of excitation light does not always protrude from the incident surface of the light emitting element 824. To drive. This correction corresponds to correcting the relative positional relationship between the phosphor layer 36 and the spot. Accordingly, it is possible to reduce the fact that the use efficiency of the excitation light is reduced due to the spot protruding from the incident surface of the light emitting element 824. Moreover, the fluctuation | variation of the intensity | strength of the light inject | emitted from a light source device can be made small.

  Also in the projector 900 of the present embodiment, as in the first to eighth embodiments, by providing the reflecting portion on the side surface of the phosphor layer 36, the light traveling inside the phosphor layer is emitted from the phosphor layer. It becomes easy to inject into the air from. As a result, the light utilization efficiency of the entire projector system can be improved.

  However, even if the various optical components are aligned at appropriate positions with the projector 900 stopped, when the projector 900 is activated and the phosphor wheel 904 is rotated at a high speed, the wheel substrate 908 is decentered or shakes. There is a possibility that the focus deviation or tracking deviation of the excitation light may occur due to the above, that is, due to the positional deviation of the incident surface of the light emitting element 824. On the other hand, in the case of the present embodiment, since the correction unit 902 that corrects the focus deviation and tracking deviation of the excitation light is provided, the light emitted from the light source device 901 is reliably corrected for the focus deviation and tracking deviation. The fluctuation of the strength of can be suppressed.

[Example 10]
FIG. 29 is a schematic configuration diagram of a projector 930 according to the tenth embodiment of the invention. The projector 930 of the present embodiment is the same as that of the ninth embodiment in that the correction unit 931 is provided, but the configuration of the correction unit 931 is different from that of the ninth embodiment.
29, the same reference numerals are given to the same components as those in FIG. 28 of the ninth embodiment, and detailed description thereof will be omitted. Also in this embodiment, the fluorescence emission surface 825 b of the light transmission layer 825 corresponds to the incident surface of the light emitting element 824.

  As shown in FIG. 29, the projector 930 of this embodiment includes a first actuator 915, a second actuator 914, a data storage unit 932, and a control unit 933 as the correction unit 931. Compared with the projector 900 of the ninth embodiment shown in FIG. 28, the light source device 934 of the projector 930 of the present embodiment detects a focus shift or tracking shift of the excitation light including an infrared laser diode and a photodetector. It is not equipped with a mechanism. Therefore, in the projector 930 of this embodiment, a simple reflection mirror may be used instead of the dichroic mirror 907.

  The positional deviation of the incident surface of the light emitting element 824 that occurs when the phosphor wheel 904 is rotated, that is, the focus deviation or tracking deviation of the excitation light, is measured in advance when the light source device 934 is assembled. The relationship between the rotation angle of the phosphor wheel 904 obtained by the measurement, the direction of the focus deviation, and the deviation amount, and the relationship between the rotation angle of the phosphor wheel 904, the direction of the tracking deviation, and the deviation amount are used as mapping data. 932.

  When the projector 930 is activated, the control unit 933 sends a drive signal for moving the pickup lens 913 in the direction parallel to the optical axis LC to the second actuator 916 based on the mapping data in the data storage unit 932. Send. Further, the control unit 933 generates a first drive signal for moving the phosphor wheel 904 in a direction perpendicular to the optical axis LC according to the tracking deviation direction and deviation amount based on the mapping data of the data storage unit 932. To the actuator 915. The second actuator 916 drives the pickup lens 913 in a direction parallel to the optical axis LC so that the light collected by the pickup lens 913 is always focused on the incident surface of the light emitting element 824 with the best focus. The first actuator 915 moves the phosphor wheel 904 in a direction perpendicular to the optical axis LC so that the light condensed by the pickup lens 913, that is, the spot of excitation light does not always protrude from the incident surface of the light emitting element 824. To drive.

  Also in the projector 930 of the present embodiment, as in the first to ninth embodiments, by providing the reflecting portion on the side surface of the phosphor layer 36, the light traveling inside the phosphor layer 36 is emitted from the phosphor layer. It becomes easy to inject into the air from the surface. As a result, the light utilization efficiency of the entire projector system can be improved. In addition, the correction unit 931 can reliably correct the focus shift and the tracking shift, and can suppress fluctuations in the intensity of light emitted from the light source device 901. Compared with the projector according to the ninth embodiment, the configuration of the correction unit 931 can be simplified because the mechanism for detecting the focus shift and the tracking shift is not provided.

The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.
For example, in Example 4, the phosphor substrate 811 in which the phosphor layer 36 is provided in the groove formed on one surface of the substrate body 812 in the same manner as the phosphor wheel 100 used in Example 1 was used. It is not limited to this. In the fourth embodiment, a phosphor substrate in which the phosphor layer 36 is provided on the substrate body 812 may be used in any of the modifications 1 to 3 and the third embodiment of the first embodiment.
Similarly, in Example 8, the phosphor substrate 891 having the phosphor layer 36 provided on one surface of the substrate body 892 in the same manner as the phosphor wheel 822 used in Example 5 was used, but the present invention is not limited thereto. . In the eighth embodiment, a phosphor substrate in which the phosphor layer 36 is provided on the substrate body 892 may be used in any of the modifications 1 to 5 of the fifth embodiment and the seventh embodiment.

  Moreover, in Example 9 and Example 10, although the structure 823 demonstrated in Example 5 was used as a structure, it is not restricted to this. In Example 9 or Example 10, any structure used in Examples 1 to 8 may be used. Further, in Example 9 and Example 10, the phosphor wheel 904 in which the structure 823 is provided in the groove formed on one main surface of the wheel substrate 908 is used as the phosphor wheel. Absent. In Example 9 or Example 10, any phosphor wheel used in Examples 1 to 3 and Examples 5 to 7 may be used.

  Further, in Example 9 and Example 10, the relative positional relationship between the phosphor layer 36 and the spot of excitation light or the spot of excitation light is reduced so as to reduce the spot from protruding from the incident surface of the light emitting element 824. The size of was corrected. In other words, the incident surface of the light emitting element 824 is a correction target. However, the present invention is not limited to this. Relative positional relationship between the phosphor layer 36 and the spot of excitation light or excitation so as to reduce the protrusion of the spot from the interface with the interface between the phosphor layer 36 and the light transmission layer 825 as a correction target. The size of the light spot may be corrected. According to this, the fluctuation | variation of the intensity | strength of the light inject | emitted from a light source device can be made still smaller.

  Further, as in the first embodiment, when excitation light is incident on the phosphor layer 36 from the excitation light incident surface 36a of the structure 32, the excitation light incident surface 36a of the structure 32 is set as a correction target. Then, if the relative positional relationship between the phosphor layer 36 and the spot of the excitation light or the size of the spot of the excitation light is corrected so as to reduce the protrusion of the spot from the incident surface 36a, the light is emitted from the light source device. The fluctuation of the intensity of the emitted light can be further reduced.

  Further, as in the third embodiment, when the light emitting element does not have the light transmission layer and the excitation light is incident on the phosphor layer 36 from the fluorescence emission surface 36b of the structure 32, the emission surface 36b is corrected. set to target.

Further, when the emission surface 36b of the phosphor layer 36 is embedded in a groove formed on one main surface of the wheel substrate 908 in the form shown in the first modification of the first embodiment, the following is performed. The correction target is set as follows. That is, in the cross section of the structure 823 in the radial direction of the wheel substrate 908, the end on the wheel substrate 908 side of the first reflecting portion 34a is one end, and the end on the wheel substrate 908 side of the second reflecting portion 34b is one end. Is defined as the incident surface of the light emitting element. And the said entrance plane is made into the object of correction | amendment.
Moreover, in Example 9 and Example 10, excitation light was condensed with respect to the incident surface of the light emitting element 824, but is not limited thereto. Regardless of the positional relationship between the excitation light condensing surface and the incident surface of the light emitting element 824 in the optical axis direction of the excitation light, as described above, the correction target is set so that the spot of the excitation light does not protrude from the correction target. You just have to correct things.
Further, it is not always necessary to collect the excitation light toward the phosphor layer 36. When the parallel excitation light is used, the second correction unit can be omitted.

  In Example 9 and Example 10, in order to efficiently use the excitation light, the positional deviation of the phosphor layer 36 is corrected so that the spot of the excitation light does not protrude from the incident surface of the light emitting element 824. However, it is not limited to this. In short, the relative position between the phosphor layer and the spot of the excitation light is reduced so that the fluctuation of the area of the region where the correction target such as the incident surface of the light emitting element 824 and the spot of the excitation light overlap each other is reduced. It is only necessary to correct at least one of the relationship and the spot size. Thereby, the fluctuation | variation of the intensity | strength of the light inject | emitted from a light source device can be made small.

  Alternatively, the first actuator 915 may be provided on the pickup lens 913 and the pickup lens 913 may be translated in a direction parallel to the main surface of the wheel substrate 908. Alternatively, the second actuator 916 may be provided in the wheel motor 33 so that the wheel substrate 908 is translated in a direction parallel to the optical axis LC.

  For example, in the above-described embodiment, an example of a configuration in which yellow light is fluorescently emitted using blue light or ultraviolet light as excitation light has been described. Instead of this configuration, it is also possible to employ a configuration in which ultraviolet light is used as excitation light, red light, green light, and blue light are fluorescently emitted, and these three colors of light are emitted in a time-sharing manner. Alternatively, red light and green light may be emitted as fluorescent light using blue light as excitation light, blue light may be emitted as it is, and light of these three colors may be emitted in a time division manner. In addition, the shape, number, arrangement, material, and the like of each component of the projector and the light source device exemplified in the above embodiment can be appropriately changed.

  DESCRIPTION OF SYMBOLS 1,600,800,820,890,900,930 ... projector, 2 ... laser diode array (light source part for excitation light) 10,610,710,810,821,881,893,901,934 ... light source device, 31, 831 ... wheel substrate, 34a ... first reflecting portion, 34b ... second reflecting portion, 35a ... first side surface, 35b ... second side surface, 36, 36R, 36G ... phosphor layer, 38 ... dichroic Film (wavelength separation layer), 72 ... reflection layer, 84a ... third reflection part, 84b ... fourth reflection part, 85a ... third side, 85b ... fourth side, 100, 200, 300, 400, 700, 822, 830, 840, 850, 860, 870, 880, 904 ... phosphor wheel (wavelength conversion element), 811, 891 ... phosphor substrate (wavelength conversion element), 825 ... light Over layer 832 ... groove, 841 ... heat-conducting portion, 861 ... uneven structure, 902,931 ... correction unit, 903 ... UV laser diode (excitation light source unit), 932 ... data storage unit.

Claims (24)

A substrate,
A light emitting device including at least a phosphor layer provided on one surface of the substrate;
Provided at least on the first side surface of the phosphor layer, the traveling direction of the light traveling inside the phosphor layer is set so that the angle with respect to the normal line of the emission surface from which the fluorescence is emitted from the light emitting element is small. A first reflecting portion to be changed;
A wavelength conversion element comprising:   The wavelength conversion element according to claim 1, wherein the substrate is rotatable about a rotation axis that intersects one surface of the substrate.   3. The wavelength conversion according to claim 2, wherein the first side surface is along one of a direction along a circle centering on the rotation axis and a direction intersecting the circle. 4. element.   Provided on the second side surface of the phosphor layer facing the first side surface, and changing the traveling direction of the light traveling inside the phosphor layer so that the angle with respect to the normal line of the emission surface becomes small The wavelength conversion element according to claim 3, further comprising a second reflection portion. Provided on the third side surface of the phosphor layer that intersects the first side surface, and changes the traveling direction of the light traveling inside the phosphor layer so that the angle with respect to the normal line of the emission surface becomes small. A third reflecting portion;
Provided on the fourth side surface of the phosphor layer facing the third side surface, and changing the traveling direction of the light traveling inside the phosphor layer so that the angle with respect to the normal line of the emission surface becomes small A fourth reflecting portion;
The wavelength conversion element according to claim 3, further comprising:   The wavelength conversion element according to claim 1, wherein the light emitting element further includes a light transmission layer provided on the opposite side of the phosphor layer from the substrate. The phosphor layer has a binder in which the phosphor is dispersed,
The wavelength conversion element according to claim 6, wherein a refractive index of the light transmission layer is the same as a refractive index of the binder.   8. The wavelength conversion element according to claim 6, wherein the wavelength conversion element has a concavo-convex structure provided on a surface of the light transmission layer opposite to the phosphor layer.   The wavelength conversion element according to claim 1, wherein the phosphor layer is provided on a surface of the substrate.   The wavelength conversion element according to claim 1, wherein the phosphor layer is provided in a groove provided in the substrate.   11. The wavelength conversion element according to claim 1, further comprising a heat conductive member provided on a side opposite to the phosphor layer of the first reflection unit.   The wavelength conversion element according to claim 11, wherein the substrate is made of metal.   2. A wavelength separation layer that is provided between the substrate and the phosphor layer, transmits excitation light that excites the phosphor, and reflects fluorescence emitted from the phosphor. The wavelength conversion element as described in any one of 1 to 12.   The reflective layer which is provided between the said board | substrate and the said fluorescent substance layer, and reflects the excitation light which excites the said fluorescent substance, and the fluorescence inject | emitted from the said fluorescent substance is characterized by the above-mentioned. The wavelength conversion element as described in any one. An excitation light source unit that emits excitation light;
A light source device comprising: the wavelength conversion element according to claim 1, which emits fluorescence upon irradiation with the excitation light.     The size of the spot of the excitation light formed on the wavelength conversion element in the cross section in the radial direction of the circle centered on the rotation axis intersecting one surface of the substrate is the incident surface of the excitation light on the light emitting element. The light source device according to claim 15, wherein the light source device is substantially the same as or smaller than the width. A drive unit that drives the wavelength conversion element so that the spot moves in time on the wavelength conversion element;
A correction unit that corrects at least one of the relative positional relationship between the phosphor layer and the spot and the size of the spot when the driving unit drives the wavelength conversion element;
The light source device according to claim 15 or 16, further comprising: The wavelength conversion element is rotatable around a rotation axis intersecting one surface of the substrate,
The light source device according to claim 17, wherein the phosphor layer is provided on one surface of the substrate along a circle centered on the rotation axis.   The light source device according to claim 17 or 18, wherein the correction unit includes a first correction unit that corrects a positional shift of the phosphor layer in a direction perpendicular to an optical axis direction of the excitation light.   The said correction | amendment part is equipped with the 2nd correction | amendment part which correct | amends the magnitude | size of the said spot by correct | amending the position shift of the said fluorescent substance layer in the optical axis direction of the said excitation light, It is characterized by the above-mentioned. The light source device according to any one of the above. A detector that detects the amount of positional deviation of the phosphor layer;
The light source device according to claim 17, wherein the correction unit corrects the positional deviation based on a detection result of the detection unit. A data storage unit for storing data indicating the amount of displacement of the phosphor layer;
The light source device according to claim 17, wherein the correction unit corrects the positional deviation based on the data stored in the data storage unit. The substrate is rotatable about a rotation axis intersecting one surface of the substrate;
The first side surface intersects with a circle centered on the rotation axis;
The wavelength conversion element is provided on a second side surface of the phosphor layer facing the first side surface, and directs light traveling in the phosphor layer in parallel with the substrate in a direction opposite to the substrate. And a second reflecting part for reflecting
F is an integral multiple of m, where F (Hz) is the pulse frequency at which the excitation light is emitted from the excitation light source unit, and m (rps) is the rotation speed of the wavelength conversion element. The light source device according to any one of claims 15 to 22.   24. A projector, wherein light emitted from the light source device according to claim 15 is modulated in accordance with an image signal and projected.

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