JP7029608B2 - Light source device and floodlight device - Google Patents

Description

The present disclosure relates to a light source device that emits light and a floodlight device using the same.

Conventionally, there is known a light source device that generates light having a predetermined wavelength by irradiating a wavelength conversion member with light emitted from a laser light source. In this light source device, for example, light that is wavelength-converted and diffused by a wavelength conversion member and light that is diffused without wavelength conversion by a wavelength conversion member are combined to produce light of a predetermined color such as white light. Generated. Such a light source device is used, for example, as a light source device for a vehicle headlight.

The following Patent Document 1 describes a vehicle lamp for scanning a wavelength conversion member with excitation light using an optical deflector provided with a mirror portion. In this vehicle lamp, the luminosity of a part of the light conversion member is increased by slowing down the reciprocating swing speed of the mirror portion. As a result, it is possible to form a luminous intensity distribution in which the luminous intensity of a part of the region (for example, the region near the center) required for the lighting fixture for a vehicle is relatively high.

Japanese Unexamined Patent Publication No. 2015-153645

In a light source device using a phosphor, in order to generate light having a higher luminous intensity, as a mirror for scanning a wavelength conversion member with light, for example, a glass plate having a dielectric multilayer film formed on the glass plate has a high reflectance. Mirrors can be used. On the other hand, in the configuration of the light source device described in Patent Document 1, when a mirror having a high reflectance is used as the mirror portion of the light deflector, the weight of the mirror is large, so that an inertial force acts on the mirror to cause the mirror. The swing speed cannot be reduced properly. Therefore, in the configuration of the light source device described in Patent Document 1, only a compact and lightweight mirror with low reflectance can be used as the mirror portion of the light deflector.

However, a mirror with low reflectance has a low light resistance of the reflective film, so if high-power and high-density light is incident on the mirror in order to generate light with higher luminous intensity, the reflective film of the mirror will be destroyed. .. As described above, it has been difficult to meet the demand for higher output of the light source device with the configuration of the light source device described in Patent Document 1.

In view of this problem, the present disclosure discloses that scanning of laser light within a predetermined scanning range even when a heavy scanning means such as a high reflectance mirror is used as the scanning means for scanning light to the wavelength conversion member. It is an object of the present invention to provide a light source device capable of controlling a light deflector appropriately and with high accuracy so that the speed becomes relatively slow, and a floodlight device using the light source device.

The first aspect of the present disclosure relates to a light source device. The light source device according to the first aspect includes a laser light source that emits laser light and an incident surface on the optical path of the laser light, converts the wavelength of the laser light into another wavelength, and produces converted light. A wavelength conversion member that diffuses the converted light and an optical deflector that scans the light on the incident surface are provided, and the optical deflector includes a movable portion, a coil, and a magnetic field that applies a magnetic field to the coil. A circuit is provided to drive the movable portion by applying a drive signal to the coil, and the strength of the magnetic field applied to the coil decreases as the movable portion moves toward a predetermined position. , The magnetic circuit is configured
Further, the predetermined position is set near the center of the entire movement range of the movable portion.

According to the light source device according to this embodiment, since the movable part is driven by using the coil and the magnetic circuit, scanning is performed appropriately and with high accuracy even when a heavy scanning means such as a mirror having high reflectance is used. You can control the means. Further, since the magnetic circuit is configured so that the strength of the magnetic field applied to the coil decreases relatively as the movable part moves toward the predetermined moving position, the moving speed of the movable part is increased in the vicinity of the predetermined moving position. It can be done relatively slowly. Therefore, the scanning speed of the laser beam can be relatively low in the scanning range corresponding to the moving range near the moving position.

Therefore, according to the light source device according to this aspect, even when a heavy scanning means such as a high reflectance mirror is used as the scanning means for scanning the light to the wavelength conversion member, the laser is used in a predetermined scanning range. The optical deflector can be controlled appropriately and with high accuracy so that the scanning speed of light becomes relatively slow.

A second aspect of the present disclosure relates to a floodlight device. The light projecting device according to the second aspect includes a light source device according to the first aspect and a projection optical system that projects light diffused by the wavelength conversion member.

According to the floodlight device according to this aspect, the same effect as that of the first aspect can be obtained.

As described above, according to the light source device and the light projecting device according to the present disclosure, even when a heavy scanning means such as a high reflectance mirror is used as the scanning means for scanning the light with respect to the wavelength conversion member. The optical deflector can be controlled appropriately and with high accuracy so that the scanning speed of the laser beam becomes relatively slow in a predetermined scanning range.

The effects or significance of the present disclosure will be further clarified by the description of the embodiments shown below. However, the embodiments shown below are merely examples for implementing the invention according to the present disclosure (hereinafter referred to as the present invention), and the present invention is described in the following embodiments. It is not limited to anything.

FIG. 1 is a perspective view showing a configuration of a floodlight device according to a first embodiment. FIG. 2 is a cross-sectional view showing the configuration of the floodlight device according to the first embodiment. FIG. 3A is a perspective view showing the configuration of the optical deflector according to the first embodiment. FIG. 3B is a cross-sectional perspective view showing the configuration of the optical deflector according to the first embodiment. FIG. 4A is an exploded perspective view showing the configuration of the magnetic circuit of the optical deflector according to the first embodiment. FIG. 4B is an exploded perspective view showing an assembly process of the optical deflector according to the first embodiment. FIG. 5A is a diagram schematically showing the configuration of the magnet of the optical deflector according to the first embodiment. FIG. 5B is a diagram schematically showing the configuration of the magnet of the optical deflector according to the first embodiment. FIG. 6A is a side view schematically showing the configuration of the wavelength conversion member according to the first embodiment. FIG. 6B is a plan view schematically showing the configuration of the wavelength conversion member according to the first embodiment. FIG. 7A is a diagram illustrating the rotational operation of the optical deflector according to the first embodiment. FIG. 7B is a diagram illustrating the rotational operation of the optical deflector according to the first embodiment. FIG. 7C is a diagram illustrating the rotational operation of the optical deflector according to the first embodiment. FIG. 8A is a diagram illustrating the rotational operation of the optical deflector according to the first embodiment. FIG. 8B is a diagram illustrating the rotational operation of the optical deflector according to the first embodiment. FIG. 8C is a diagram illustrating the rotational operation of the optical deflector according to the first embodiment. FIG. 9A is a graph schematically showing the change in the angular velocity of the movable portion according to the first embodiment. FIG. 9B is a graph schematically showing the luminous intensity at each position on the incident surface of the wavelength conversion member according to the first embodiment. FIG. 10A is a graph showing a drive signal in the verification according to the first embodiment. FIG. 10B is a graph showing the magnetic flux density in the verification according to the first embodiment. FIG. 10C is a graph showing the angular velocity in the verification according to the first embodiment. FIG. 11A is a graph showing a drive signal in the verification according to the comparative example. FIG. 11B is a graph showing the magnetic flux density in the verification according to the comparative example. FIG. 11C is a graph showing the angular velocity in the verification according to the comparative example. FIG. 12A is a schematic view showing the configuration of the magnet of the optical deflector according to the first modification. FIG. 12B is a schematic view showing the configuration of the magnet of the optical deflector according to the first modification. FIG. 12C is a schematic diagram showing the configuration of the magnet according to the second modification. FIG. 12D is a schematic diagram showing the configurations of the magnet and the non-magnetic material according to the third modification. FIG. 13 is a perspective view showing the configuration of the optical deflector according to the second embodiment. FIG. 14A is a cross-sectional perspective view showing the configuration of the optical deflector according to the second embodiment. FIG. 14B is a cross-sectional perspective view showing the configuration of the optical deflector according to the second embodiment. FIG. 15A is an exploded perspective view showing the configuration of the magnetic circuit according to the second embodiment. FIG. 15B is an exploded perspective view for explaining the assembly of the optical deflector according to the second embodiment. FIG. 16A is a diagram schematically showing the configuration of the magnet of the optical deflector according to the second embodiment. FIG. 16B is a diagram schematically showing the configuration of the magnet of the optical deflector according to the second embodiment. FIG. 17 is a diagram schematically showing a scanning state of laser light in the wavelength conversion member according to the second embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. For convenience, the X, Y, and Z axes that are orthogonal to each other are added to each figure. The X-axis direction and the Y-axis direction are the width direction and the depth direction of the floodlight device, respectively, and the Z-axis direction is the height direction of the floodlight device. The positive direction of the Z axis is the projection direction of light in the floodlight device.

<First Embodiment>
FIG. 1 is a perspective view showing the configuration of the floodlight device 1 according to the first embodiment. FIG. 2 is a cross-sectional view showing the configuration of the light projecting apparatus 1 according to the first embodiment. FIG. 2 shows a cross-sectional view of the floodlight 1 cut at the center position in the X-axis direction in a plane parallel to the YY plane.

With reference to FIGS. 1 and 2, the light projecting device 1 includes a light source device 2 that generates light and a projection optical system 3 for projecting the light generated by the light source device 2. The projection optical system 3 includes two lenses 3a and a lens 3b, and the light from the light source device 2 is collected by these lenses 3a and 3b and projected onto a target region. The projection optical system 3 does not necessarily have to be composed of only two lenses 3a and 3b, and may include, for example, another lens or mirror. Further, the projection optical system 3 may be configured to collect the light from the light source device 2 by a concave mirror.

The light source device 2 has a configuration in which various members are installed on the base 11. Specifically, as a configuration for generating light for projection, a laser light source 12, a collimator lens 13, an optical deflector 14, and a wavelength conversion member 15 are installed on the base 11. The collimator lens 13 is installed on the base 11 via the holder 16.

The laser light source 12 emits laser light in the blue wavelength band (for example, 450 nm) in the positive direction of the Z axis. The laser light source 12 is made of, for example, a semiconductor laser. The wavelength of the laser beam emitted from the laser light source 12 can be appropriately changed. Further, the laser light source 12 does not necessarily have to emit laser light in a single wavelength band, and may be, for example, a multi-light emitting semiconductor laser in which a plurality of light emitting elements are mounted on one substrate.

The collimator lens 13 converts the laser light emitted from the laser light source 12 into parallel light. The position of the collimator lens 13 in the optical axis direction may be adjusted so that the laser light emitted from the laser light source 12 can be converged.

The optical deflector 14 includes a mirror 17, and by rotating the mirror 17 with respect to the rotation axis L1, the traveling direction of the laser beam passing through the collimator lens 13 is changed. The incident surface of the mirror 17 is a flat surface. The mirror 17 is, for example, a mirror having a high reflectance in which a dielectric multilayer film is formed on a glass plate. The rotation axis L1 is included in the YZ plane and is provided in a direction forming a predetermined angle with respect to the Z axis. The incident surface of the mirror 17 is parallel to the X-axis in the neutral position and is tilted by a predetermined angle with respect to the surface parallel to the XX plane. The configuration of the optical deflector 14 will be described later with reference to FIGS. 3A to 5B.

The wavelength conversion member 15 is arranged at a position where the laser beam reflected by the mirror 17 is incident. The wavelength conversion member 15 is a rectangular plate-shaped member, and is installed on the base 11 so that the incident surface is parallel to the XY plane and the longitudinal direction is parallel to the X axis. As described above, as the mirror 17 rotates about the rotation axis L1, the wavelength conversion member 15 is scanned in the longitudinal direction by the laser beam.

The wavelength conversion member 15 converts a part of the incident laser light into a wavelength different from the blue wavelength band and diffuses it in the Z-axis direction. The other laser light that has not been wavelength-converted is diffused in the Z-axis direction by the wavelength conversion member 15. The two types of light diffused in this way are combined to generate light of a predetermined color. The light of each wavelength is taken into the projection optical system 3 and projected onto the target region.

In the first embodiment, a part of the laser beam is converted into light in the yellow wavelength band by the wavelength conversion member 15. Diffused light in the yellow wavelength band after wavelength conversion and scattered light in the blue wavelength band that has not been wavelength-converted are combined to generate white light. The wavelength after wavelength conversion does not have to be in the yellow wavelength band, and the color of the generated light may be a color other than white. The configuration of the wavelength conversion member 15 will be described later with reference to FIGS. 6A and 6B.

A circuit board 18 is installed on the lower surface of the base 11. A circuit for controlling the laser light source 12 and the light deflector 14 is mounted on the circuit board 18. As shown in FIG. 1, the terminal portion of the circuit board 18 is exposed to the outside on the positive side of the Y-axis of the base 11.

3A and 3B are perspective views and cross-sectional perspective views showing the configuration of the optical deflector 14, respectively. FIG. 3B shows a cross section of the optical deflector 14 of FIG. 3A cut along the IIIB-IIIB line segment in a plane parallel to the xz plane at the center position in the y-axis direction by hatching. .. 4A is an exploded perspective view showing the configuration of the magnetic circuit 14a, and FIG. 4B is an exploded perspective view showing the assembly process of the optical deflector 14.

For convenience, FIGS. 3A to 4B newly show x, y, and z axes in order to explain the configuration of the optical deflector 14. Of these, the x-axis is in the same direction as the X-axis shown in FIGS. 1 and 2. The x, y, and z axes are the X, Y, and Z axes shown in FIGS. 1 and 2, rotated around the X axis by a predetermined angle. The y-axis corresponds to the lateral direction of the optical deflector 14, and the z-axis corresponds to the height direction of the optical deflector 14. Here, for convenience, the negative side of the z-axis is defined as the upper side of the optical deflector 14.

The optical deflector 14 is configured to drive the mirror 17 by using an electromagnetic force. A component for electromagnetic drive is installed in the housing 101.

The housing 101 has a rectangular parallelepiped shape that is long in the x-axis direction. A rectangular recess 101a is formed on the upper surface of the housing 101 in a plan view. Further, in the housing 101, bosses 101b are formed on the upper surfaces of the positive and negative edges of the x-axis, respectively. The two bosses 101b are arranged at an intermediate position in the y-axis direction of the housing 101. The housing 101 is made of a highly rigid metal material.

As shown in FIGS. 3A and 4B, a frame-shaped leaf spring 102 is installed on the upper surface of the housing 101. The leaf spring 102 has a frame portion 102a, a support portion 102b, two beam portions 102c, and two holes 102d.

At the intermediate position in the x-axis direction, two beam portions 102c are formed so as to extend parallel to the frame portion 102a in the y-axis direction, and the frame portion 102a and the support portion 102b are connected by these beam portions 102c. .. The support portion 102b is rectangular in a plan view, and two beam portions 102c are connected to the support portion 102b at an intermediate position in the x-axis direction of the support portion 102b. Like the boss 101b, the hole 102d on the positive side of the x-axis is circular in a plan view, and the hole 102d on the negative side of the x-axis has a long shape in the x-axis direction in a plan view. The leaf spring 102 has a shape symmetrical in the y-axis direction and a shape symmetrical in the x-axis direction except for the two holes 102d. The leaf spring 102 is integrally formed of a flexible metal material.

The two holes 102d are provided at positions corresponding to the two bosses 101b, respectively. As shown in FIGS. 3A and 4B, the leaf spring 102 is fixed to the upper surface of the housing 101 by four screws 103 with the boss 101b fitted in the hole 102d. The mirror 17 is fixed to the upper surface of the support portion 102b with an adhesive or the like. The mirror 17 is substantially square in plan view. The axis connecting the two beam portions 102c is the rotation axis L1 of the mirror 17. That is, the two beam portions 102c are provided along the rotation axis L1 of the mirror 17. The pair of beam portions 102c elastically support the support portions 102b and the mirror 17 from both sides in the y-axis direction along the rotation axis L1.

The laser beam from the laser light source 12 is incident on the central position of the mirror 17 from an oblique direction with respect to the incident surface of the mirror 17. That is, the laser light from the laser light source 12 is incident on the mirror 17 so that the rotation axis L1 and the central axis of the laser light intersect.

The coil 104 is mounted on the lower surface of the support portion 102b. The coil 104 orbits a rectangular shape with rounded corners in a plan view. The coil 104 is installed on the lower surface of the support portion 102b so that the intermediate position of the long side coincides with the rotation shaft L1. The coil 104, the support portion 102b, and the mirror 17 form the movable portion 14b of the optical deflector 14.

Two sets of magnets 105 and 106 are arranged so as to sandwich the x-axis positive side and the x-axis negative side portions of the coil 104 in the x-axis direction, respectively. As shown in FIG. 4A, the magnet 105 and the magnet 106 are installed on the wall portion 107a and the wall portion 107b of the yoke 107, respectively. In this state, the two holes 107c formed in the yoke 107 and the two bosses 101c formed on the bottom surface of the recess 101a of the housing 101 are combined, and the yoke 107 is installed on the bottom surface of the recess 101a of the housing 101. The magnetic circuit 14a is composed of two sets of magnets 105, magnets 106, and yoke 107.

A magnetic field generated by the magnet 105 and the magnet 106 on the positive side of the x-axis, a magnetic field generated by the magnet 105 and the magnet 106 on the negative side of the x-axis, and a drive signal (current) applied to the coil 104 around the rotation axis L1. The driving force is excited by the coil 104. As a result, the mirror 17 rotates about the rotation shaft L1. At this time, the pair of beam portions 102c of the leaf spring 102 are elastically deformed.

In the first embodiment, the magnet 105 and the magnet 106 have three magnets stacked in the z-axis direction, respectively. The magnetic poles and thicknesses of these three magnets are adjusted so that the angular velocity of the movable portion 14b is reduced in the rotation range of the mirror 17 in the rotation range near the neutral position in the rotation operation of the mirror 17.

The "neutral position" is the position of the mirror 17 when the drive signal (current) is not applied to the coil 104. In the configuration of the first embodiment, the support portion 102b and the support portion 102b are as shown in FIG. 3A. The position of the mirror 17 when the mirror 17 is not rotated in any direction with respect to the rotation axis L1 and is in a state parallel to the xy plane. Hereinafter, for convenience, the position of the movable portion 14b when the mirror 17 is in the neutral position is also referred to as a neutral position.

5A and 5B are diagrams schematically showing the configurations of magnets 105 and 106, respectively. FIG. 5A is a view of the installation positions of the magnets 105 and 106 on the positive side of the x-axis in the negative direction of the y-axis, and FIG. 5B shows the installation positions of the magnets 105 and 106 on the negative side of the x-axis in the negative direction of the y-axis. It is a figure that I saw. For convenience, in FIGS. 5A and 5B, characters indicating the magnetic poles of the magnets are added.

As shown in FIGS. 5A and 5B, the magnet 105 has a configuration in which two magnets 105a are superposed on the upper surface and the lower surface of the magnet 105b, and the magnet 106 has two magnets 106a on the upper surface of the magnet 106b. It is configured to be stacked on the bottom surface. The magnet 105a and the magnet 106a are installed on the yoke 107 so that different magnetic poles face each other. The magnet 105b and the magnet 106b are also installed in the yoke 107 so that different magnetic poles face each other. The magnets 105a and 106a and the magnets 105b and 106b have different magnetic poles facing the gap between the magnets 105 and 106.

The positions and widths of the upper magnet 105a and the upper magnet 106a in the z-axis direction are the same as each other. Further, the positions and widths of the lower magnet 105a and the lower magnet 106a in the z-axis direction are also the same as each other. Further, the positions and widths of the magnet 105b in the middle stage and the magnet 106b in the middle stage in the z-axis direction are also the same. The width of the magnets 105a and 105b in the middle stage in the z-axis direction is smaller than the widths of the magnets 105a and 106a in the upper and lower stages in the z-axis direction. The widths of the magnets 105b and 106b are adjusted according to the braking force to be applied to the movable portion 14b in order to decelerate the movable portion 14b near the neutral position in the movable portion 14b rotation operation.

In the first embodiment, the magnetic poles of the magnets are set as shown in FIGS. 5A and 5B, and the width and magnetic force of the magnets are adjusted so that the magnets 105b and 106b are indicated by the arrows of the long chain line. The direction of the magnetic field between the magnet 105a and the magnet 106a is opposite to the direction of the magnetic field between the magnet 105a and the magnet 106a. As a result, the angular velocity of the mirror 17 can be relatively reduced in the angle range described in the neutral position of the mirror 17. The rotation operation of the mirror 17 will be described later with reference to FIGS. 7A to 8C.

FIG. 6A is a side view schematically showing the configuration of the wavelength conversion member 15.

The wavelength conversion member 15 has a structure in which a reflective film 202 and a phosphor layer 203 are laminated on the upper surface of the substrate 201.

The substrate 201 is made of, for example, silicon, aluminum nitride ceramic, or the like.

The reflective film 202 is configured by laminating a first reflective film 202a and a second reflective film 202b. The first reflective film 202a is, for example, a metal film such as Ag, Ag alloy, or Al. The second reflective film 202b also has a function of protecting the first reflective film 202a from oxidation and the like as well as reflection. For example, SiO ₂ , ZnO, ZrO ₂ , Nb ₂ O ₅ , Al ₂ O ₃ , and TIO ₂ , SiN, AlN and the like, it is composed of one or more layers of a dielectric. The reflective film 202 does not necessarily have to be composed of the first reflective film 202a and the second reflective film 202b, and may be composed of a single layer or a laminated structure of three or more layers.

The fluorescent material layer 203 is formed by fixing the fluorescent material particles 203a with a binder 203b. The phosphor particles 203a emit fluorescence in the yellow wavelength band by being irradiated with the laser light in the blue wavelength band emitted from the laser light source 12. As the phosphor particles 203a, for example, (Y _n Gd _1-n ) ₃ (Aluminum Ga _{1-m ) 5} O ₁₂ : Ce (0.5 ≦ n ≦ 1, 0.5) having an average particle diameter of 1 μm to 30 μm. ≦ m ≦ 1) is used. Further, as the binder 203b, a transparent material mainly containing silsesquioxane such as polymethylsilsesquioxane is used.

Further, as the second particles, the phosphor layer 203 may be mixed with fine particles of Al ₂ O ₃ having an average particle diameter of 0.1 μm to 10 μm and a thermal conductivity of 30 W / (m · K). In this case, the second particles are mixed at a ratio of 10 vol% or more and 90 vol% or less with respect to the phosphor particles 203a. For example, as the second particle, Al ₂ O ₃ (refractive index 1.8), which has a large difference in refractive index from silsesquioxane (refractive index 1.5), which is the material of the binder 203b, is used. With this configuration, the light scattering property inside the phosphor layer 203 can be improved, and the thermal conductivity of the phosphor layer 203 can be increased. In addition, vol% means volume%.

Further, it is preferable to provide the void 203c inside the phosphor layer 203. In the first embodiment, the void 203c formed near the center of the phosphor layer 203 and the void 203c formed near the interface with the reflective film 202 are provided on the phosphor layer 203.

Here, the void 203c formed inside the phosphor layer 203 is configured so that the closer it is to the reflective film 202, the higher the density. With this configuration, the laser light that has entered the inside can be scattered more efficiently and taken out from the light source device 2. Further, since the void 203c formed near the interface with the reflective film 202 is in contact with the second reflective film 202b which is a dielectric, the laser light and the fluorescence are effectively scattered while reducing the energy loss due to the metal surface. Can be made to.

The arrangement of the void 203c as described above is made by forming the wavelength conversion member 15 using a phosphor paste in which a fluorescent particle 203a made of YAG: Ce and a binder 203b made of polysilsesquioxane are mixed. It can be easily formed. Specifically, the phosphor particles 203a and the second particles are formed on the substrate 201 (reflection film 202) using a phosphor paste mixed with a binder 203b in which polysilsesquioxane is dissolved in an organic solvent. After that, the organic solvent in the paste is vaporized by performing high temperature annealing at about 200 ° C. At this time, since the organic solvent vaporized from the portion of the wavelength conversion member 15 close to the substrate 201 is easily retained, the void 203c can be easily formed in the portion close to the substrate 201. By such a manufacturing method, a high-density void 203c can be easily formed in the vicinity of the reflective film 202.

The phosphor layer 203 further contains a filler 203d for increasing the strength and heat resistance. The difference in the refractive index between the filler 203d and the binder 203b is set to be large as well as the difference in the refractive index between the phosphor particles 203a and the binder 203b.

The laser light emitted from the laser light source 12 irradiates the excited region R1 shown in FIG. 6A, and is scattered and absorbed on the surface or inside of the phosphor layer 203. At this time, a part of the laser beam is converted into light in the yellow wavelength band by the phosphor particles 203a and emitted from the phosphor layer 203. Further, the other part of the laser beam is scattered without being converted into the light of the yellow wavelength band, and is emitted from the phosphor layer 203 as the light of the blue wavelength band. At this time, since the light in each wavelength band is scattered while propagating in the phosphor layer 203, it is emitted from the light emitting region R2 wider than the excited region R1.

As described above, the phosphor layer 203 is configured so that the refractive index difference between the binder 203b and the phosphor particles 203a and the refractive index difference between the binder 203b and the filler 203d are both large, thereby scattering light. It can be easily facilitated, and the propagation of light inside the phosphor layer 203 can be suppressed. As a result, light can be emitted from the light emitting region R2, which is slightly wider than the excited region R1. Further, in the first embodiment, the void 203c is further arranged on the phosphor layer 203 to enhance the scattering of light. As a result, the excited region R1 and the light emitting region R2 can be further brought closer to each other.

FIG. 6B is a plan view schematically showing the configuration of the wavelength conversion member 15.

The wavelength conversion member 15 has a rectangular shape long in the X-axis direction in a plan view. The wavelength conversion member 15 is scanned in the X-axis direction by the laser beam by rotating the mirror 17 of the optical deflector 14. In FIG. 6B, B1 indicates the beam spot of the laser beam. The beam spot B1 reciprocates the incident surface 15a of the wavelength conversion member 15 in the width W1.

For example, a triangular wave-shaped drive signal (current) having a zero level as the amplitude center is applied to the coil 104. By the driving force excited by the coil 104 by this driving signal, the mirror 17 rotates with the support portion 102b with a predetermined rotation width around the neutral position. As a result, the laser beam (beam spot B1) reflected by the mirror 17 reciprocates on the incident surface 15a of the wavelength conversion member 15 in the width W1.

The region of the beam spot B1 on the incident surface 15a corresponds to the excited region R1 of FIG. 6A. While the beam spot B1 moves on the incident surface 15a of the wavelength conversion member 15, the diffused light in the blue wavelength band and the diffused light in the yellow wavelength band from the light emitting region R2 slightly wider than the region of the beam spot B1 are in the positive direction of the Z axis. Be radiated.

The light of the two wavelength bands thus emitted is taken in by the projection optical system 3 shown in FIGS. 1 and 2 and projected onto the target region. As a result, white light, which is a combination of light in the blue wavelength band and light in the yellow wavelength band, is projected from the floodlight device 1 to the target region.

7A to 8C are diagrams illustrating the rotational operation of the movable portion 14b of the optical deflector 14. For convenience, only the mirror 17 and the coil 104 are shown as the configuration of the movable portion 14b, and the support portion 102b is not shown. 7A to 8C schematically show cross-sectional views of the magnet 105 and the vicinity of the magnet 106 when viewed from the positive side of the y-axis.

In FIGS. 7A to 8C, the broken line arrow indicates the direction of the magnetic field, the solid line arrow indicates the direction of the driving force generated in the coil 104, and the dotted line arrow indicates the rotation direction of the mirror 17. Further, in FIGS. 7A to 8C, the direction of the current of the coil 104 portion in which the gap between the magnets 105 and 106 is inserted is shown by a symbol indicating the direction. Further, in FIGS. 7A to 8C, a character indicating the magnetic pole facing the coil 104 among the magnetic poles of each magnet is added to each magnet. In the following description, the rotation direction of the movable portion 14b is the rotation direction when viewed in the negative direction of the y-axis.

FIG. 7A shows a state in which the mirror 17 is most rotated clockwise. In this state, the mirror 17 and the coil 104 are stopped. As shown in FIG. 7A, the driving signal (current) applied to the coil 104 generates a driving force in the portion of the coil 104 (hereinafter referred to as “excited portion 104a”) sandwiched between the magnets 105 and 106. Due to this driving force and the elastic return force of the leaf spring 102, the movable portion 14b starts to rotate in the counterclockwise direction.

After that, as shown in FIG. 7B, when the exciting portion 104a of the coil 104 exceeds the vicinity of the boundary between the magnets 105a and 106a and the magnets 105b and 106b, the direction of the magnetic field applied to the exciting portion 104a is reversed. As a result, the driving force generated in the exciting portion 104a is reversed, and a torque (braking force) in a direction opposite to the rotation of the coil 104 is generated. This torque (braking force) reduces the rotational speed (angular velocity) of the movable portion 14b. Also in this case, the movable portion 14b continues to rotate counterclockwise due to the inertial force.

After that, as shown in FIG. 7C, when the mirror 17 reaches the neutral position, the drive signal (current) applied to the coil 104 becomes zero. The drive signal (current) applied to the coil 104 gradually decreases from the timing of FIG. 7A toward the timing of FIG. 7C, and becomes zero at the timing of FIG. 7C. Then, after the timing of FIG. 7C, the polarity of the drive signal (current) applied to the coil 104 is inverted, and then the magnitude of the drive signal (current) is gradually increased by the polarity after the inversion.

Further, when the exciting portion 104a of the coil 104 exceeds the position shown in FIG. 8A, that is, near the boundary between the magnets 105a and 106a and the magnets 105b and 106b, the direction of the magnetic field applied to the exciting portion 104a of the coil 104 is reversed. do. Here, during the period from the timing of FIG. 7C to the timing of FIG. 8A, a driving force in the direction of promoting the rotation of the coil 104 is generated in the exciting portion 104a of the coil 104. The solid arrow in FIG. 8A indicates this driving force. Due to this driving force, the rotational speed (angular velocity) of the movable portion 14b increases in the period from the timing of FIG. 7C to the timing of FIG. 8A.

When the exciting portion 104a of the coil 104 exceeds the vicinity of the boundary between the magnet 105a, the magnet 106a and the magnet 105b, and the magnet 106b, the direction of the magnetic field applied to the exciting portion 104a is reversed again, and the exciting portion 104a is accompanied by this. The driving force generated in is reversed. As a result, torque (braking force) in a direction opposite to the rotation of the movable portion 14b is generated. Due to this torque (braking force), the rotational speed (angular velocity) of the movable portion 14b gradually decreases.

After that, when the counterclockwise rotation of the movable portion 14b advances to the position shown in FIG. 8B, the rotation of the movable portion 14b is stopped. Therefore, the position of FIG. 8B is the maximum rotation position of the movable portion 14b in the counterclockwise direction. The maximum counterclockwise rotation angle with respect to the neutral position is the same as the maximum clockwise rotation angle with respect to the neutral position shown in FIG. 7A. After that, the movable portion 14b starts rotating in the clockwise direction by the driving force generated in the exciting portion 104a of the coil 104 and the elastic return force of the leaf spring 102.

Also in this rotation operation, as shown in FIG. 8C, when the exciting portion 104a of the coil 104 exceeds the vicinity of the boundary between the magnet 105a, the magnet 106a and the magnet 105b, and the magnet 106b, it is applied to the exciting portion 104a of the coil 104. The direction of the magnetic field is reversed, and a torque (braking force) in a direction opposite to the rotation of the coil 104 is generated. This torque (braking force) reduces the rotational speed (angular velocity) of the movable portion 14b. After that, the movable portion 14b rotates clockwise in the reverse process of FIGS. 7C to 8B. As a result, the movable portion 14b returns to the position shown in FIG. 7A. After that, the movable portion 14b repeats the same rotation operation.

FIG. 9A is a graph schematically showing a change in the angular velocity of the movable portion 14b (support portion 102b, coil 104, mirror 17) of the optical deflector 14. In FIG. 9A, the horizontal axis is the rotation angle of the movable portion 14b of the optical deflector 14. In the graph of FIG. 9A, the angular velocity of the movable portion 14b in the range from the maximum rotation angle (−θ1) in the clockwise direction to the maximum rotation angle (+ θ1) in the counterclockwise direction is shown. The angles −θ2 and + θ2 are rotation angles when the coil 104 is located near the boundary between the magnet 105a, the magnet 106a and the magnet 105b, and the magnet 106b (reversal position of the magnetic field).

As shown in FIG. 9A, as the rotation angle approaches −θ1 to −θ2, the angular velocity of the movable portion 14b increases due to the driving force in the rotation promoting direction generated in the coil 104 and the elastic return force of the leaf spring 102. When the rotation angle reaches −θ2, the angular velocity becomes maximum. Then, when the rotation angle approaches 0 from −θ2, the angular velocity of the movable portion 14b gradually decreases due to the driving force in the braking direction generated in the coil 104. After that, as the rotation angle approaches + θ2 from 0, the angular velocity of the movable portion 14b gradually increases due to the driving force in the rotation promotion direction generated in the coil 104, and when the rotation angle reaches + θ2, the angular velocity increases. Become the maximum. Then, when the rotation angle approaches + θ1 from + θ2, the angular velocity decreases due to the driving force in the braking direction generated in the coil 104, and when the rotation angle becomes + θ1, the angular velocity of the movable portion 14b becomes zero. Similarly, when the rotation angle changes from + θ1 to −θ1, the angular velocity of the movable portion 14b also changes.

Thus, when the rotation angle is in the range between −θ2 and + θ2, the angular velocity of the movable portion 14b is relatively slower than the angular velocity of the movable portion 14b when the rotation angles are −θ2 and + θ2. become.

FIG. 9B is a graph schematically showing the luminous intensity (light intensity per unit time) at each position on the incident surface 15a of the wavelength conversion member 15. In the graph of FIG. 9B, the horizontal axis corresponds to the position of the beam spot B1 on the incident surface 15a in the moving direction, that is, the position in the X-axis direction in FIG. 6B. When the rotation angles of the support portion 102b are −θ1, −θ2, 0, + θ2, and + θ1, the positions of the beam spots B1 on the incident surface 15a are P1, P2, P3, P4, and P5, respectively.

As described above, when the movable portion 14b of the optical deflector 14 is in the range of the rotation angle −θ2 to + θ2, the angular velocity of the movable portion 14b becomes relatively low. As a result, as shown in FIG. 9B, the luminosity on the incident surface 15a between the positions P2 and P4 is relatively higher than the luminosity on the incident surface 15a at the positions P2 and P4.

<Verification>
The inventors verified the change in speed of the movable portion 14b when the optical deflector 14 of the first embodiment was used by simulation in comparison with a comparative example. In the comparative example, the magnets 105 and 106 are each composed of one magnet, and the magnets 105 and 106 are arranged so that the direction of the magnetic field between the magnets 105 and 106 is in the negative x-axis direction.

The conditions for the simulation of the first embodiment were set as follows.

(1) Moment of inertia of the movable portion 14b composed of the coil 104, the support portion 102b and the mirror 17: 2.6 g · m ²
(2) Weight of moving part 14b: 150 mg
(3) Material of coil 104: Copper clad aluminum (4) Size of coil 104, etc .: Width 14 mm, length 10 mm, thickness 0.8 mm, 45 turns (5) Material of magnet 105a, magnet 105b, magnet 106a, magnet 106b : Neodi permanent magnet (6) Residual magnetic flux density of magnet 105a, magnet 105b, magnet 106a, magnet 106b: 1.39T
(7) Thickness of magnet 105a and magnet 106a: 1.35 mm
(8) Thickness of magnet 105b and magnet 106b: 0.7 mm
(9) Material of yoke 107: Steel (SS400)
In the comparative example, instead of the simulation conditions (7) and (8) above, single magnets 105 and 106 having a thickness of 3.4 mm in the z-axis direction were assumed. The materials and residual magnetic flux densities of these magnets 105 and 106 were the same as in (5) and (6) above.

Under the above conditions, the angular velocity of the movable portion 14b when the movable portion 14b was rotated in a range of 2.5 degrees in the positive and negative directions with respect to the neutral position was verified.

FIG. 10C is a graph showing the simulation result of the angular velocity when the optical deflector 14 according to the first embodiment is used. In the verification of the first embodiment, as shown in FIG. 10A, a triangular wave-shaped drive signal (voltage) having a zero level as the amplitude center was applied, and the magnetic flux density was set as shown in FIG. 10B. On the horizontal axis of FIG. 10A, the application timing of the drive signal is indicated by the rotation angle of the movable portion 14b. Further, the magnetic flux density in FIG. 10B is the magnetic flux density applied to the exciting portion 104a of the coil 104 when the movable portion 14b is located at the rotation angle of the horizontal axis. The vertical axes of the graphs of FIGS. 10A to 10C are all standardized with the maximum value set to 1.

FIG. 11C is a graph showing the simulation result of the angular velocity when the optical deflector 14 according to the comparative example is used. In the verification of the comparative example, as shown in FIG. 11A, a triangular wave-shaped drive signal (voltage) is applied as in the first embodiment, and as shown in FIG. 11B, the magnetic flux density applied to the exciting portion 104a of the coil 104. Was set constant over the entire angle range. The vertical axis of the graphs of FIGS. 11A to 11C is also standardized with the maximum value set to 1.

As shown in FIG. 11C, in the comparative example, the angular velocity of the movable portion 11b reached the maximum value without decelerating in the vicinity of the neutral position. On the other hand, in the first embodiment, as shown in FIG. 10C, the angular velocity of the movable portion 14b was reduced in the vicinity of the neutral position.

As described above, in the configuration of the first embodiment, it was confirmed that the angular velocity of the movable portion 14b can be reduced in the vicinity of the neutral position, unlike the comparative example, by setting the magnetic flux density as shown in FIG. 9B. As a result, in the first embodiment, it was confirmed that the scanning speed of the laser beam is relatively reduced and the amount of light projected on the target region is increased in the scanning range near the center of the wavelength conversion member 15.

<Effect of embodiment>
As described above, according to the first embodiment, the following effects are achieved.

As shown in FIGS. 3A to 4B, since the movable portion 14b (mirror 17, support portion 102b and coil 104) is driven by using the coil 104 and the magnetic circuit 14a, a high reflectance mirror or the like has a high weight. Even when the scanning means of the above is used, the mirror 17 can be controlled appropriately and with high accuracy.

Further, as shown in FIG. 10B, the magnetic circuit 14a is such that the strength (magnetic flux density) of the magnetic field applied to the coil 104 relatively decreases as the movable portion 14b moves toward the neutral position (predetermined movement range). Is configured. Therefore, as shown in FIG. 10C, the angular velocity of the movable portion 14b can be relatively reduced in the vicinity of the neutral position. That is, in the angular range (−θ2 to + θ2) shown in FIG. 9A, the angular velocity of the movable portion 14b can be relatively reduced. Therefore, as shown in FIG. 9B, the scanning speed of the laser beam can be relatively low in the scanning range (positions P2 to P4) near the center corresponding to the angle range (−θ2 to + θ2) near the neutral position.

Therefore, according to the first embodiment, even when a high-weight mirror 17 such as a high-reflectance mirror is used as a scanning means for scanning the wavelength conversion member 15 with light, the laser is used in the scanning range near the center. The optical deflector 14 can be controlled appropriately and with high accuracy so that the scanning speed of light is relatively low.

In the first embodiment, as shown in FIG. 10B, the strength (magnetic flux density) of the magnetic field applied to the coil 104 is the minimum in the angular range near the neutral position, and therefore, as shown in FIG. 10C. In addition, the angular velocity of the movable portion 14b can be reduced near the neutral position. However, the range for reducing the angular velocity of the movable portion 14b is not limited to the vicinity of the neutral position, and may be another range. In this case, the angular position at which the strength (magnetic flux density) of the magnetic field applied to the coil 104 is minimized is appropriately changed according to the range in which the angular velocity of the movable portion 14b is reduced.

Further, in the first embodiment, as shown in FIG. 10B, the magnetic circuit 14a has the magnetic circuit 14a so that the direction of the magnetic field is reversed in the angle range (about −1.3 ° to about + 1.3 °) including the neutral position. It is configured. Therefore, in the range where the angle within this angle range is negative, the torque for suppressing the rotation of the movable portion 14b can be applied to the movable portion 14b. Therefore, the angular velocity of the movable portion 14b can be effectively weakened in the vicinity of the neutral position.

Here, the strength of the magnetic field in the angle range (about −1.3 ° to about + 1.3 °) including the neutral position is set to a strength that can reduce the angular velocity of the movable portion 14b as shown in FIG. 10B. Has been done. As a result, as shown in FIG. 10C, the angular velocity of the movable portion 14b near the neutral position can be relatively reduced.

Further, as shown in FIGS. 5A, 5B and 7A to 8C, the magnetic circuit 14a is configured such that the magnetic pole facing the coil 104 changes as the movable portion 14b moves. More specifically, in the magnetic circuit 14a, the first magnetic pole (magnet 105b, magnetic pole 106b) facing the coil 104 when the movable portion 14b is located in the neutral position, and the moving direction (z-axis direction) of the movable portion 14b. ), The second magnetic poles (magnets 105a, 106a) which are arranged at positions sandwiching the first magnetic pole and are different from the first magnetic pole are provided. As a result, the magnetic field (magnetic flux density) shown in FIG. 10B can be realized.

Here, in the first embodiment, the first magnetic pole and the second magnetic pole are configured by combining a plurality of magnets (two magnets 105a and 105b, two magnets 106a and a magnet 106b). According to this configuration, the magnetic field (magnetic flux density) shown in FIG. 10B can be easily realized by adjusting the strength and width of each magnet.

Further, as shown in FIGS. 5A, 5B and 7A to 8C, the width of the first magnetic pole (magnet 105b, magnetic pole 106b) in the moving direction (z-axis direction) of the movable portion 14b is the movable portion 14b. It is set smaller than the width of the second magnetic pole (magnet 105a, magnetic pole 106a) in the moving direction (z-axis direction) of. As a result, the rotation range to which the braking force is applied can be narrowed, and the rotation range to which the driving force in the propulsion direction is applied can be widened. Therefore, the movable portion 14b can be smoothly and stably moved in the vicinity of the neutral position. The rotation speed of the movable portion 14b can be reduced.

<First change example>
The embodiment of the present disclosure is not limited to the above-mentioned first embodiment, and various modifications can be made. Hereinafter, a modified example of the first embodiment will be described.

FIG. 12A is a side view showing the configuration of the magnetic circuit 14a according to the first modification. FIG. 12A shows a view of the positive side of the x-axis of the magnetic circuit 14a in the negative direction of the y-axis. Since the portion of the magnetic circuit 14a on the negative side of the x-axis is the same as in FIG. 12A, the illustration is omitted.

In the first modification, the magnet 105b and the magnet 106b of the first embodiment are replaced with the non-magnetic material 108 and the non-magnetic material 109, respectively. The non-magnetic material 108 and the non-magnetic material 109 are made of, for example, plastic.

In the magnetic circuit 14a of the first modification, unlike the first embodiment, the direction of the magnetic field is not reversed in the rotation range near the neutral position. However, in the magnetic circuit 14a of the first modification, since the non-magnetic material 108 and the non-magnetic material 109 are arranged in the rotation range near the neutral position, the magnet 105 and the magnet 106 are arranged in the rotation range near the neutral position. The magnetic field strength of the gap between them can be reduced to near zero. Therefore, in this configuration, the change in the angular velocity of the movable portion 14b becomes gradual in the rotation range near the neutral position. As a result, the angular velocity of the movable portion 14b in the vicinity of the neutral position can be reduced as compared with the case of the comparative examples shown in FIGS. 11A to 11C. Therefore, in the scanning range near the center of the wavelength conversion member 15, the scanning speed of the laser beam can be reduced as compared with the case of the comparative example, and the amount of light generated near the center of the wavelength conversion member 15 can be increased. ..

As shown in FIG. 12B, the non-magnetic material 108 and the non-magnetic material 109 may be omitted, and a gap may be provided between the magnets 105a arranged in the z-axis direction. Also in this case, similarly to the configuration of FIG. 12A, the magnetic field strength of the gap between the magnets 105 and 106 can be reduced to near zero in the rotation range near the neutral position. Therefore, the same effect as the configuration of FIG. 12A can be achieved.

Even with the configuration of the first embodiment, when the width of the magnet 105b and the magnet 106b in the z-axis direction is small, or when the magnetic force of the magnet 105b and the magnet 106b is small, the direction of the magnetic field in the rotation range near the neutral position is There may be cases where it does not reverse. However, also in this case, as compared with the configurations of FIGS. 12A and 12B, the magnetic flux of the magnets 105b and 106b can more smoothly reduce the strength of the magnetic field in the rotation range near the neutral position to near zero. Therefore, also in this case, as compared with the case of the comparative examples shown in FIGS. 11A to 11C, the angular velocity of the movable portion 14b in the vicinity of the neutral position can be reduced, and the amount of light generated from the vicinity of the center of the wavelength conversion member 15 is increased. be able to.

<Second modification example>
FIG. 12C is a side view showing the configuration of the magnetic circuit 14a according to the second modification. FIG. 12C shows a view of the positive side of the x-axis of the magnetic circuit 14a in the negative direction of the y-axis. Since the portion of the magnetic circuit 14a on the negative side of the x-axis is the same as in FIG. 12C, the illustration is omitted.

As shown in FIG. 12C, in the second modification, the distance between the magnetic pole surfaces of the interrupted magnets 105b and 106b facing each other is smaller than the distance between the magnetic pole surfaces of the upper and lower magnets 105a and 106a facing each other. It has become. With this configuration, in the second modification, the strength of the opposite magnetic field in the rotation range near the neutral position can be further increased, and the movable portion 14b can be more effectively decelerated near the neutral position.

In the configuration of FIG. 12C, both the magnetic pole surfaces of the magnets 105b and 106b in the middle stage facing each other protrude from the magnetic pole surfaces of the magnets 105a and 106a in the upper and lower stages, respectively. Only one of the magnetic pole surfaces of the magnet 105b and the magnet 106b facing each other may protrude from one of the magnetic pole surfaces of the upper and lower magnets 105a and 106a facing each other. The positions of the magnetic pole surfaces of the magnets 105b and 106b facing each other in the x-axis direction can be appropriately adjusted according to the strength of the magnetic field to be applied to the coil 104 in the rotation range near the neutral position.

<Third change example>
The number of magnets stacked to form the magnet 105 and the magnet 106 does not necessarily have to be three as in the first embodiment.

For example, as shown in FIG. 12D, the magnet 105b in the first embodiment is replaced with one magnet 105c and two magnets 105d, and the magnet 106b in the first embodiment is one magnet 106c and two magnets. It may be replaced with 106d. Here, the two magnets 105d are installed on the z-axis positive side and the z-axis negative side surfaces of the magnet 105c, respectively, and the two magnets 106d are the z-axis positive side and the z-axis negative side surfaces of the magnet 106c, respectively. It is installed in each. The magnetic forces of the magnet 105c and the magnet 106c are the same, and the magnetic forces of the magnet 105d and the magnet 106d are the same. The magnet 105c, the magnet 105d, the magnet 106c, and the magnet 106d are all arranged so that the north pole faces in the positive direction of the x-axis.

According to this configuration, the magnetic force of the magnet 105c and the magnet 106c is different from the magnetic force of the magnet 105d and the magnet 106d, or the width of the magnet 105c and the magnet 106c in the z-axis direction and the z-axis direction of the magnet 105d and the magnet 106d. By making the width different from that of, the distribution of the magnetic field in the rotation range near the neutral position can be adjusted more finely. As a result, the braking force applied to the movable portion 14b can be finely adjusted in the rotation range near the neutral position.

The number of magnets arranged in the z-axis direction in the rotation range near the neutral position is not limited to the number shown in FIG. 12D. Further, the magnet 105a may also be configured by combining a plurality of magnets having different magnetic forces or thicknesses.

<Second Embodiment>
In the first embodiment, the optical deflector 14 has a configuration in which the mirror 17 is rotated by one axis. On the other hand, in the second embodiment, the optical deflector 14 is configured so that the mirror 17 can rotate about two rotation axes orthogonal to each other.

In the second embodiment, since the mirror 17 can be driven in two axes, the scanning locus of the laser beam on the incident surface 15a of the wavelength conversion member 15 is different from that in the first embodiment. In the second embodiment, as will be described later, a plurality of scanning lines are set on the incident surface 15a of the wavelength conversion member 15, and the size of the beam spot scanning the incident surface 15a of the wavelength conversion member 15 is set accordingly. It is narrowed down as compared with the embodiment. Other configurations of the floodlight device 1 and the light source device 2 are the same as those in the first embodiment.

The size of the beam spot is reduced to a smaller size by adjusting the distance between the laser light source 12 and the collimator lens 13, the numerical aperture of the collimator lens 13, and converging the laser beam with the collimator lens 13. Can be done. In addition, the reflecting surface of the mirror 17 may have a concave shape so that the laser beam can be converged.

FIG. 13 is a perspective view showing the configuration of the optical deflector 14 according to the second embodiment. 14A and 14B are cross-sectional perspective views showing the configuration of the optical deflector 14 according to the second embodiment, respectively. FIG. 14A shows a cross-sectional view of XIVA-XIVA in which the optical deflector 14 of FIG. 13 is cut at the center position in the y-axis direction in a plane parallel to the xz plane, and FIG. 14B shows a cross-sectional view taken along the yz plane. A cross-sectional view of XIVB-XIVB is shown in which the optical deflector 14 of FIG. 13 is cut at the center position in the x-axis direction in a parallel plane. FIG. 15A is an exploded perspective view showing the configuration of the magnetic circuit 14a according to the second embodiment, and FIG. 15B is an exploded perspective view showing an assembly process of the optical deflector 14 according to the second embodiment. 13 to 15B show the same x, y, and z axes as in FIGS. 3A and 3B.

Housing 111 has a rectangular parallelepiped shape that is long in the x-axis direction. A rectangular recess 111a is formed on the upper surface of the housing 111 in a plan view. The housing 111 is made of a highly rigid metal material.

As shown in FIGS. 13 and 15B, a frame-shaped leaf spring 112 is installed on the upper surface of the housing 111. The leaf spring 112 has an outer frame portion 112a, an inner frame portion 112b, two beam portions 112c, a support portion 112d, and two beam portions 112e. At the intermediate position in the y-axis direction, two beam portions 112c are formed so as to extend parallel to the outer frame portion 112a in the x-axis direction, and the outer frame portion 112a and the inner frame portion 112b are connected by these beam portions 112c. Has been done. Further, at an intermediate position in the x-axis direction, two beam portions 112e are formed so as to extend parallel to the inner frame portion 112b in the y-axis direction, and the inner frame portion 112b and the support portion 112d are formed by these beam portions 112e. It is connected.

The inner frame portion 112b has a contour with rounded rectangular corners in a plan view, and two beam portions 112c are connected to the inner frame portion 112b at an intermediate position in the y-axis direction of the inner frame portion 112b. Further, the support portion 112d has a rectangular contour in a plan view, and two beam portions 112e are connected to the support portion 112d at an intermediate position in the x-axis direction of the support portion 112d. The leaf spring 112 has a shape symmetrical in the x-axis direction and the y-axis direction. The leaf spring 112 is integrally formed of a flexible metal material.

As shown in FIG. 15B, the leaf spring 112 is fixed to the upper surface of the housing 111 by the four screws 113 with the outer frame portion 112a placed on the upper surface of the housing 111. The mirror 17 is fixed to the upper surface of the support portion 112d with an adhesive or the like. The mirror 17 is substantially square in plan view. The axis connecting the two beam portions 112e is the rotation axis L1 of the mirror 17 for scanning the laser beam in the longitudinal direction of the wavelength conversion member 15, as in the first embodiment. Further, the axis connecting the two beam portions 112c becomes the rotation axis L2 of the mirror 17 for changing the scanning line of the laser beam in the wavelength conversion member 15.

As in the first embodiment, the laser beam from the laser light source 12 is incident on the center position of the mirror 17. That is, the laser light from the laser light source 12 is incident on the mirror 17 so that the central axis of the laser light penetrates the position where the rotation shaft L1 and the rotation shaft L2 intersect.

The coil 114 is mounted on the lower surface of the support portion 112d. The coil 114 orbits a rectangular shape with rounded corners in a plan view. The coil 114 is installed on the lower surface of the support portion 112d so that the intermediate position of the long side coincides with the rotation shaft L1. The coil 114, the support portion 112d, and the mirror 17 form the movable portion 14b of the optical deflector 14.

Two sets of magnets 115 and magnets 116 are arranged so as to sandwich the coil 114 in the x-axis direction. As shown in FIG. 15A, the magnet 115 and the magnet 116 are installed on the wall portion 117a and the wall portion 117b of the yoke 117, respectively. In this state, the two holes 117c formed in the yoke 117 and the two bosses 111c formed in the bottom surface of the recess 111a of the housing 111 are combined, and the yoke 117 is installed in the bottom surface of the recess 111a of the housing 111. The configurations of the magnets 115 and the magnets 116 and the method of setting the magnetic poles of each set are the same as those of the magnets 105 and 106 shown in FIGS. 3A and 3B.

Further, the coil 118 is mounted on the lower surface of the inner frame portion 112b. The coil 118 has the same shape as the inner frame portion 112b in a plan view. The coil 118 is installed on the lower surface of the inner frame portion 112b so that the intermediate position of the short side coincides with the rotation shaft L2. The coil 118 and the inner frame portion 112b form a second movable portion of the optical deflector 14.

As shown in FIG. 13, magnets 119 are arranged on the positive side of the y-axis and the negative side of the y-axis with respect to the coil 114, respectively. As shown in FIG. 15A, these magnets 119 are installed on the wall portion 117d of the yoke 117. Further, these two magnets 119 are installed on the yoke 117 so that the magnetic poles facing the coil 118 are different from each other. The magnetic circuit 14a is composed of these two magnets 119, two sets of magnets 115 and 116, and a yoke 117.

By adjusting the magnetic poles of the two magnets 119 in this way, when a drive signal (current) is applied to the coil 118, the inner frame portion 112b of the rotation shaft L2 rotates, depending on the magnitude of the drive signal. The inner frame portion 112b is tilted by the angle. That is, the inner frame portion 112b is tilted from the neutral position shown in FIG. 13 by an angle in which the elastic recovery force generated in the beam portion 112c and the electromagnetic force excited by the coil 118 are balanced. At this time, the mirror 17 rotates together with the support portion 112d as the inner frame portion 112b rotates.

The support portion 112d rotates about the rotation shaft L1 by applying a drive signal (current) to the coil 114, as in the configuration of FIGS. 3A and 3B. As the support portion 112d rotates, the mirror 17 rotates about the rotation shaft L1. As described above, according to the optical deflector 14 of the second embodiment, the mirror 17 is rotated by the rotation shaft L1 and the rotation shaft by independently applying the drive signal (current) to the coil 114 and the coil 118, respectively. It can be rotated individually with respect to L2.

16A and 16B are diagrams schematically showing the configurations of the magnet 115 and the magnet 116, respectively. FIG. 16A is a view of the installation position of the magnet 115 on the positive side of the x-axis and the magnet 116 in the negative direction of the y-axis, and FIG. 16B shows the installation position of the magnet 115 and the magnet 116 on the negative side of the x-axis in the negative direction of the y-axis. It is a view seen in the direction. For convenience, in FIGS. 16A and 16B, characters indicating the magnetic poles of the magnets are added.

As shown in FIGS. 16A and 16B, the configurations and magnetic poles of the magnet 115 and the magnet 116 are the same as the configurations and magnetic poles of the magnet 105 and the magnet 106 shown in FIGS. 5A and 5B. That is, the magnet 115 has a structure in which two magnets 115a are superposed on the upper surface and the lower surface of the magnet 115b, and the magnet 116 has a structure in which two magnets 116a are superposed on the upper surface and the lower surface of the magnet 116b. Therefore, the magnetic circuit 14a applies a magnetic field to the coil 114 with the same intensity distribution as in the first embodiment. Therefore, also in the second embodiment, as in the first embodiment, the movable portion 14b is driven so that the angular velocity in the rotation range near the neutral position is relatively reduced.

FIG. 17 is a diagram schematically showing a scanning state of laser light in the wavelength conversion member 15.

As shown in FIG. 17, in the second embodiment, a plurality of scanning lines SL1 are set on the incident surface 15a of the wavelength conversion member 15. In the example of FIG. 17, three scanning lines SL1 are set on the incident surface 15a. However, the number of scanning lines SL1 is not limited to this.

The beam spot B2 of the laser beam is positioned at the start position on the positive side of the X-axis of the second-stage scanning line SL1 after moving the uppermost scanning line SL1 to the end position in the positive direction of the X-axis. After that, the beam spot B2 moves the second-stage scanning line SL1 to the end position in the negative direction of the X-axis, and then is positioned at the start position on the negative side of the X-axis of the third-stage scanning line SL1. Similarly, when the beam spot B2 moves to the end position on the positive side of the X-axis of the third-stage scanning line SL1, the beam spot B2 is positioned at the start position of the second-stage scanning line SL1. After that, the beam spot B2 moves the second-stage scanning line SL1 to the end position in the negative direction of the X-axis, and then is positioned at the start position on the negative side of the X-axis of the first-stage scanning line SL1. Hereinafter, the same scanning is repeated for the three scanning lines SL1.

The movement of the beam spot B2 along the scanning line SL1 is performed by rotating the mirror 17 with respect to the rotation axis L1 shown in FIG. The change of the scanning line SL1 is performed by rotating and tilting the mirror 17 with respect to the rotation axis L2 shown in FIG. The optical deflector 14 is controlled by the control circuit mounted on the circuit board 18 of FIG. 1 so that the beam spot B2 scans the incident surface 15a of the wavelength conversion member 15 as described above.

During the period when the beam spot B2 moves from the end position of one scanning line SL1 to the start position of the next scanning line SL1, the emission of the laser beam from the laser light source 12 is stopped. That is, the feed lines TL1 and TL2 in FIG. 17 show the movement locus of the beam spot B2 when the laser beam is emitted, and in actual control, the laser light source 12 at the feed lines TL1 and TL2. Is controlled to be off.

The method of scanning the laser beam with respect to the incident surface 15a of the wavelength conversion member 15 is not limited to the above. For example, the incident surface 15a of the wavelength conversion member 15 is scanned by laser light so that the beam spot B2 reciprocates on each scanning line SL1 and then jumps to the start position of the next scanning line SL1. There may be.

According to the configuration of the second embodiment, as described above, since the angular velocity of the movable portion 14b is decelerated in the rotation range near the neutral position, the scanning speed in the vicinity of the center of each scanning line SL1 can be decelerated. Therefore, the amount of light generated near the center of the wavelength conversion member 15 can be increased.

Further, according to the configuration of the second embodiment, the wavelength conversion member 15 is scanned along the plurality of scanning lines SL1 at the more narrowed beam spot B2, so that, for example, white light can be generated on the light emitting region R2. The region where the light emission is stopped and the region where the light emission of the white light is generated can be set in more detail. Therefore, when the white light generated from the light source device 2 is projected onto the target region by the projection optical system 3, the region where the projection of the white light is stopped and the region where the white light is projected are further set on the target region. Can be set in detail. Therefore, for example, when the light projecting device 1 is incorporated in the headlight of a vehicle, the white light irradiation region and the non-irradiation region are set more finely according to the position of an oncoming vehicle and the position of a pedestrian. be able to.

<Other changes>
Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments.

For example, in the first embodiment, the magnetic poles shown in FIGS. 5A and 5B are set by the configuration in which the three magnets are overlapped in the z-axis direction. However, the present invention is not limited to this, and the magnet 105, the magnet 106, the magnet 115, and the magnet 116 may each be composed of one magnet, and the magnetic poles shown in FIGS. 5A and 5B may be set by magnetizing each magnet. .. Similar changes can be made in the second embodiment.

Further, in the first embodiment, the magnet 105 and the magnet 106 are arranged so as to sandwich the coil 104, but the magnet 105 and the magnet 106 do not necessarily have to be arranged so as to sandwich the coil 104, and the coil 104 is desired. If a magnetic field can be applied by the intensity distribution, either the magnet 105 or the magnet 106 may be omitted. Similar changes can be made in the second embodiment.

Further, the magnet 105b and the two magnets 105a do not necessarily have to directly overlap each other, and may be overlapped with each other via a gap or another member.

Further, in the first embodiment and the second embodiment, the movable portion 14b is configured to rotate about the rotation shaft L1, but the movable portion 14b is configured to be swingably supported by the housing 101. May be good. Further, the thicknesses of the upper magnet 105a and the magnet 106a and the lower magnet 105a and the magnet 106a may be different from each other. The waveform of the drive signal does not have to be a triangular wave that changes linearly as shown in FIG. 10A, and may be, for example, a slightly curved waveform. The distribution of the magnetic field may be adjusted according to the waveform of the drive signal so that the angular velocity in a predetermined rotation range becomes relatively gentle.

Further, in the first embodiment and the second embodiment, the light source device 2 is configured to use the reflection type wavelength conversion member 15, but the light source device 2 is configured to use the transmission type wavelength conversion member 15. May be.

Further, the shapes of the leaf spring 102 and the leaf spring 112 are not necessarily limited to the shapes shown in the first and second embodiments, and for example, in FIG. 3A, they are sandwiched between two screws 103 adjacent to each other in the x-axis direction. The area of the frame portion 102a other than the specified area may be omitted.

Further, the shape of the mirror 17 does not necessarily have to be a square in a plan view, and may be a rectangle or a circle in a plan view. The shape of the support portion 102b can also be changed as appropriate.

In the first embodiment, as shown in FIG. 3A, one of the two holes 102d provided with the leaf spring 102 is a long hole, but both of the two holes 102d are long holes before tightening the screw 103. In addition, the leaf spring 102 may be slightly movable in the longitudinal direction. In this case, a feeler gauge having a desired thickness may be inserted to determine the position of the leaf spring 102, and then the screw 103 may be tightened. Alternatively, the position of the leaf spring 102 may be adjusted in the longitudinal direction while measuring the gap between the coil 104, the magnet 105, and the magnet 106 with a measuring device to determine the position, and then the screw 103 may be tightened.

Further, the reflective surface of the mirror 17 does not necessarily have to be a flat surface, and may have a concave shape that can impart a converging effect to the laser beam. In this case, the concave surface shape may be adjusted so that the shapes of the beam spots B1 and the beam spots B2 on the incident surface 15a of the wavelength conversion member 15 can be formed into substantially linear shapes in the Y-axis direction. Alternatively, a lens for forming the shapes of the beam spots B1 and the beam spots B2 on the incident surface 15a of the wavelength conversion member 15 into a predetermined shape may be mounted on the reflecting surface of the mirror 17.

Further, the type of the phosphor particles 203a included in the phosphor layer 203 of the wavelength conversion member 15 does not necessarily have to be one type, and for example, a plurality of types that generate fluorescence of different wavelengths by the laser light from the laser light source 12. The fluorescent material particles 203a of the above may be contained in the fluorescent material layer 203. In this case, the diffused light of fluorescence generated from each type of phosphor particles 203a and the diffused light of the laser light not wavelength-converted by these phosphor particles 203a generate light of a predetermined color.

In addition, various modifications of the embodiments of the present disclosure can be made as appropriate within the scope of the technical idea shown in the claims.

According to the light source device and the light projecting device of the present disclosure, even when a heavy scanning means such as a high reflectance mirror is used, the scanning speed of the laser beam is relatively slow in a predetermined scanning range. The optical deflector can be controlled appropriately and with high accuracy. Thereby, the light source device and the light projecting device of the present disclosure can increase the amount of light projected on the target region, which is industrially useful.

1 Floodlight 2 Light source device 3 Projection optics 3a, 3b Lens 11 Base 12 Laser light source 13 Collimeter lens 14 Optical deflector 14a Magnetic circuit 11b, 14b Moving part 15 Wavelength conversion member 15a Incident surface 16 Holder 17 Mirror 18 Circuit board 101 , 111 Housing 101a, 111a Recesses 101b, 101c, 111c Boss 102, 112 Leaf spring 102b, 112d Support 102a Frame 112a Outer frame 112b Inner frame 102c, 112c, 112e Beam 102d Hole 103, 113 Screw 104, 114 , 118 Coil 105, 105a, 105b, 105c, 105d, 106, 106a, 106b, 106c, 106d, 115, 115a, 115b, 116, 116a, 116b, 119 Magnet 107, 117 York 107a, 107b, 117a, 117b, 117d Wall 107c, 117c Hole 108, 109 Non-magnetic material L1, L2 Rotating shaft SL1 Scan line

Claims (8)

A laser light source that emits laser light, and a wavelength conversion member that has an incident surface on the optical path of the laser light and converts the wavelength of the laser light to another wavelength to generate converted light and diffuses the converted light. A light deflector that scans the light on the incident surface.
The optical deflector includes a movable portion, a coil, and a magnetic circuit that applies a magnetic field to the coil, and is configured to drive the movable portion by applying a drive signal to the coil.
The magnetic circuit is configured so that the strength of the magnetic field applied to the coil decreases as the movable portion moves toward a predetermined position.
Further, the predetermined position is set near the center of the entire movement range of the movable portion.
A light source device characterized by that. In the light source device according to claim 1 ,
The magnetic circuit is configured so that the direction of the magnetic field is reversed in the movement range including the predetermined position.
A light source device characterized by that. In the light source device according to claim 2 ,
The strength of the magnetic field in the moving range including the predetermined position is set to the strength that reduces the moving speed of the movable portion.
A light source device characterized by that. In the light source device according to any one of claims 1 to 3 .
The magnetic circuit is configured such that the magnetic pole facing the coil changes as the movable portion moves.
A light source device characterized by that. In the light source device according to claim 4 ,
The magnetic circuit is arranged at a position where the first magnetic pole facing the coil when the movable portion is located at the predetermined position and a position sandwiching the first magnetic pole in the moving direction of the movable portion, respectively. A second magnetic pole, which is different from the magnetic pole of
A light source device characterized by that. In the light source device according to claim 5 ,
By combining a plurality of magnets, the first magnetic pole and the second magnetic pole are configured.
A light source device characterized by that. In the light source device according to claim 5 ,
The width of the first magnetic pole in the moving direction of the movable portion is set to be smaller than the width of the second magnetic pole in the moving direction of the movable portion.
A light source device characterized by that. The light source device according to any one of claims 1 to 7.
A projection optical system for projecting the converted light, and the like.
A floodlight that features that.

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