JP7727170B2 - Phosphor wheel device and light-emitting module - Google Patents

Description

This disclosure relates to a phosphor wheel device and a light-emitting module.

A known technology involves using a light-emitting element and a phosphor wheel device, directing light from the light-emitting element onto the phosphor wheel to extract fluorescence. Patent Document 1 also discloses an illumination device equipped with a detector that detects light from a detection pattern in order to detect abnormalities in a rotating plate provided with a phosphor layer.

Patent Publication No. 2015-031876

The present disclosure aims to provide a device with a mechanism that can detect the direction of rotation of a phosphor wheel.

The phosphor wheel device disclosed in the embodiment comprises a phosphor wheel having a substrate, a wavelength conversion unit including one or more phosphors that convert the wavelength of light and provided on the substrate, and first and second detection units provided on the substrate, a support member that rotatably supports the phosphor wheel, and a drive unit that rotates the phosphor wheel around the rotation axis of the phosphor wheel, wherein the wavelength conversion unit is arranged to pass through a first circumference that is centered on the rotation axis and has a radius of a first value, and the first and second detection units are arranged to pass through a first circumference that is centered on the rotation axis and has a radius of a first value. The first and second detection units are arranged to pass through a second circumference having a different second value, and when the value of the smallest radius of the circumference centered on the rotation axis and passed by at least one of the first and second detection units is defined as a third value, and the value of the largest radius of the circumference centered on the rotation axis and passed by at least one of the first and second detection units is defined as a fourth value, on a circumference having a radius of a fifth value in the range from the third value to the fourth value, the length of the first detection unit passing on the circumference and the length of the second detection unit passing on the circumference are different.

The light-emitting module disclosed in the embodiment also includes the phosphor wheel device disclosed in the embodiment; one or more first light-emitting devices that emit light having a first wavelength as a peak wavelength to the wavelength conversion unit; a light-emitting unit that emits detection light to a position through which the first and second detection units pass as the phosphor wheel rotates; and a light-receiving unit that receives the detection light.

According to an embodiment of the present disclosure, the rotation direction of the phosphor wheel can be detected, making it possible to confirm that it is operating in the correct rotation direction.

FIG. 1 is a plan view of a light-emitting module according to an embodiment. FIG. 2 is a perspective view of a phosphor wheel device according to an embodiment. FIG. 2 is a plan view of a phosphor wheel according to the embodiment. 3B is a graph showing an example of the change over time in the amount of light received by the rotation detection unit when the phosphor wheel shown in FIG. 3A rotates clockwise. 3B is a graph showing an example of the change over time in the amount of light received by the rotation detection unit when the phosphor wheel shown in FIG. 3A rotates counterclockwise. 4 is a cross-sectional view of the phosphor wheel shown in FIG. 3A taken along line IV-IV. FIG. 10 is a plan view of a phosphor wheel according to a modified example. 5B is a graph showing an example of the change over time in the amount of light received by the rotation detection unit when the phosphor wheel shown in FIG. 5A rotates clockwise. 5B is a graph showing an example of the change over time in the amount of light received by the rotation detection unit when the phosphor wheel shown in FIG. 5A rotates counterclockwise. FIG. 10 is a plan view of a phosphor wheel according to a modified example. 6B is a graph showing an example of the change over time in the amount of light received by the rotation detection unit when the phosphor wheel shown in FIG. 6A rotates clockwise. 6B is a graph showing an example of the change over time in the amount of light received by the rotation detection unit when the phosphor wheel shown in FIG. 6A rotates counterclockwise. FIG. 10 is a plan view of a phosphor wheel according to a modified example. FIG. 10 is a plan view of a phosphor wheel according to a modified example. 8B is a graph showing an example of the change over time in the amount of light received by the rotation detection unit when the phosphor wheel shown in FIG. 8A rotates clockwise. 8B is a graph showing an example of the change over time in the amount of light received by the rotation detection unit when the phosphor wheel shown in FIG. 8A rotates counterclockwise. FIG. 10 is a plan view of a phosphor wheel according to a modified example. 9B is a graph showing an example of the change over time in the amount of light received by the rotation detection unit when the phosphor wheel shown in FIG. 9A rotates clockwise. 9B is a graph showing an example of the change over time in the amount of light received by the rotation detection unit when the phosphor wheel shown in FIG. 9A rotates counterclockwise. FIG. 10 is a plan view of a light-emitting module according to a modified example.

In this specification and claims, polygons such as triangles and quadrilaterals are referred to as polygons, including shapes in which the corners have been rounded, chamfered, corner-cut, rounded, etc. Furthermore, shapes in which processing has been applied not only to the corners (edges of the sides) but also to the middle of the sides are also referred to as polygons. In other words, shapes that have been partially processed while retaining the polygonal base are included in the interpretation of "polygon" as described in this specification and claims.

The same applies to words that describe specific shapes, such as trapezoids, circles, and irregularities, not just polygons. The same also applies when dealing with the sides that make up that shape. In other words, even if the corners or middle of a side have been modified, the interpretation of "side" includes the modified parts. Note that when distinguishing a "polygon" or "side" that has no partial modification from a modified shape, the word "strict" is added, for example, "strict quadrilateral."

Furthermore, in this specification or claims, expressions such as up and down, left and right, front and back, front and back, front and back, and front and back merely describe relative positions, orientations, directions, and other relationships, and do not necessarily correspond to the relationships during use. For example, even if a component is mounted so that its top surface is positioned on the side of the finished product, the top surface of the component remains unchanged.

Furthermore, in this specification or claims, when there are multiple equivalents to a certain element and each of them needs to be distinguished, the elements may be distinguished by adding "first" or "second" to the beginning of the element.

Below, with reference to the drawings, a description of an embodiment of the present invention will be given. However, while the illustrated embodiment embodies the technical concept of the present invention, it does not limit the present invention. Furthermore, in the following description, the same names and symbols indicate the same or similar components, and duplicate explanations may be omitted as appropriate. Note that the size and positional relationships of components shown in each drawing may be exaggerated for ease of understanding.

<Embodiment>
A light-emitting module 1000 according to an embodiment will be described. FIGS. 1 to 4 are plan views showing an exemplary embodiment of the light-emitting module 1000. FIG. 1 omits the rotation detection unit 60. Also, FIG. 1 illustrates a portion of the light beam with a dotted line. FIG. 2 is a perspective view of the phosphor wheel device 200 and the rotation detection unit 60. FIG. 3A is a plan view of the phosphor wheel 100 as seen from the light output surface side. FIG. 3A also illustrates the axle 41 of the support member 40 and the light receiving section 62 of the rotation detection unit 60. FIGS. 3B and 3C are graphs showing an example of the change over time in the amount of light received by the rotation detection unit 60. FIG. 4 is a cross-sectional view of the phosphor wheel 100 taken along the line IV-IV shown in FIG. 3A.

The light-emitting module 1000 comprises multiple components. These components include one or more first light-emitting devices 410, a phosphor wheel device 200, and a rotation detection unit 60. The light-emitting module 1000 emits wavelength-converted light based on the light emitted from the one or more first light-emitting devices 410 to the outside. The light-emitting module 1000 is housed in a housing 600.

The multiple components may include one or more optical elements. The one or more optical elements include, for example, a condenser lens, a collimator lens, and a mirror. Note that other optical elements may also be included. Furthermore, some or all of these optical elements may not be included. The light-emitting module 1000 illustrated in FIG. 1 includes multiple first light-emitting devices 410 and multiple optical elements that control the light emitted from the multiple first light-emitting devices 410. The multiple optical elements include a first condenser lens 511, a first collimator lens 512, and a first mirror 513.

The light-emitting module 1000 can be configured to include one or more second light-emitting devices 420. The light-emitting module 1000 can further be configured to include one or more third light-emitting devices 430. The light-emitting module 1000 illustrated in FIG. 1 includes a plurality of second light-emitting devices 420 and a plurality of third light-emitting devices 430. The light-emitting module 1000 includes a second condenser lens 521, a second collimator lens 522, and a second mirror 523 as optical elements that control the light emitted from the plurality of second light-emitting devices 420, and a third condenser lens 531, a diffusion member 300, a third collimator lens 532, and a third mirror 533 as optical elements that control the light emitted from the plurality of third light-emitting devices 430.

The light-emitting module 1000 illustrated in FIG. 1 converts the wavelength of light emitted from a plurality of first light-emitting devices 410 and a plurality of second light-emitting devices 420, and emits the wavelength-converted light to the outside. The light-emitting module 1000 also emits light emitted from a plurality of third light-emitting devices 430 to the outside without converting the wavelength. The light-emitting module 1000 controls these lights and emits them to the outside either separately or combined. The separate lights or combined light can be extracted to the outside, for example, through a light extraction port 700 formed in the housing 600.

Each of the above-mentioned components will now be described.
(First light-emitting device 410)
One or more first light emitting devices 410 emit light having a first wavelength as a peak wavelength. Here, a plurality of first light emitting devices 410 are arranged on the same plane. The light emitting elements of the first light emitting devices 410 emit light of the same color. However, they may emit light of different colors.

As an example, a semiconductor laser element is used as the light-emitting element. LEDs, organic EL elements, etc. may also be used. For example, the light-emitting element may use light whose emission peak wavelength is in the range of 365 nm to 494 nm. However, light with a peak wavelength outside this range may also be used. Furthermore, it does not have to be limited to the wavelength range of visible light. Light with a peak wavelength in the wavelength range of ultraviolet light may also be used.

The light-emitting elements may include light-emitting elements that emit blue light. The light-emitting elements may also include light-emitting elements that emit purple light. However, light-emitting elements that emit light of other colors may also be used.

Here, blue light refers to light whose emission peak wavelength is in the range of 430 nm to 494 nm. Purple light refers to light whose emission peak wavelength is in the range of 365 nm to 430 nm. Examples of light-emitting elements that emit blue or purple light include semiconductor laser elements that contain nitride semiconductors. Examples of nitride semiconductors that can be used are GaN, InGaN, and AlGaN.

(Phosphor wheel device 200)
Phosphor wheel device 200 has phosphor wheel 100, support member 40, and drive unit 50. Phosphor wheel device 200 is able to output outgoing light having a wavelength different from that of incident light by wavelength conversion unit 20 included in phosphor wheel 100.

(Phosphor wheel 100)
Phosphor wheel 100 has a substrate 10. Phosphor wheel 100 further has a wavelength conversion unit 20, a first detection unit 31, and a second detection unit 32 provided on substrate 10. Phosphor wheel 100 has a rotation axis A1, and is used while rotating around rotation axis A1. One surface of phosphor wheel 100 is a light input surface, and the surface opposite the input surface is a light output surface.

(Substrate 10)
The substrate 10 is a plate-like member. The shape of the substrate 10 is, for example, a disk. In the phosphor wheel 100, as shown in FIG. 2 , the substrate 10 is a disk-shaped light-transmitting substrate. For example, a sapphire substrate can be used as the light-transmitting substrate.

(First detection unit 31 and second detection unit 32)
As shown in FIG. 3A , the detection unit 30 is a region that blocks or reflects irradiated light. The detection unit 30 includes a first detection unit 31 and a second detection unit 32. The detection unit 30 may further include a third detection unit. The detection unit 30 only needs to be able to block or reflect light of a specific wavelength from the irradiated light. The detection unit 30 can be formed of the same material as the wavelength conversion unit 20. For example, a detection unit 30 formed of a YAG phosphor can be used for infrared light irradiated onto the detection unit 30. The first detection unit 31 and the second detection unit 32 are provided, for example, on the surface of a light-transmitting substrate 10.

(Wavelength conversion unit 20)
The wavelength conversion unit 20 includes one or more phosphors that convert the wavelength of light. Phosphors have the property of absorbing light within a specific wavelength range as excitation light and emitting light of a different wavelength from the absorbed light as fluorescence. As a phosphor that uses blue light as excitation light, for example, a garnet-based phosphor such as YAG or LAG can be used.

The wavelength conversion unit 20 converts the wavelength of light within the wavelength range that serves as excitation light for the phosphor and emits the converted light. However, even within the wavelength range that serves as excitation light, some light may be transmitted without being wavelength converted. For this reason, the light emitted from the wavelength conversion unit 20 may include incident light that passes through the wavelength conversion unit 20.

The wavelength conversion section 20 can be, for example, circular or polygonal ring-shaped. The wavelength conversion section 20 can also be configured to have multiple wavelength conversion regions. In the phosphor wheel 100 illustrated in FIG. 3A, the first wavelength conversion region 21A and the second wavelength conversion region 22A are formed as non-overlapping circular regions. The first wavelength conversion region 21A is provided outside the second wavelength conversion region 22A. The first wavelength conversion region 21A and the second wavelength conversion region 22A contain different types of phosphors. They may also contain the same type of phosphor. For example, the first wavelength conversion region 21A can contain a LAG phosphor, and the second wavelength conversion region 22A can contain a YAG phosphor.

The wavelength conversion unit 20, first detection unit 31, and second detection unit 32 are provided on the substrate 10. When the phosphor wheel 100 rotates around the rotation axis A1, the wavelength conversion unit 20, first detection unit 31, and second detection unit 32 describe a circle centered on the rotation axis A1.

As shown in Figure 3A, a coordinate axis of radius R is depicted with the rotation axis A1 as the origin. The first wavelength conversion region 21A is arranged so as to pass through a first circumference having a radius of a first value R1 and centered on the rotation axis A1. The second wavelength conversion region 22A may have a circumference having a radius of a first value R1 and centered on the rotation axis A1, and the radius of the circumference passing through the second wavelength conversion region 22A may be a first value R1. The radius of the circumference passing through the second wavelength conversion region 22A is a value smaller than the radius of the circumference passing through the first wavelength conversion region 21A. The first detection unit 31 and the second detection unit 32 are arranged so as to pass through a second circumference having a radius of a second value R2 and centered on the rotation axis A1, the radius of which is different from the first value R1. Here, of the circumferences through which at least one of the first detection unit 31 and the second detection unit 32 passes, the radius of the circumference with the smallest radius is defined as a third value R3, and the radius of the circumference with the largest radius is defined as a fourth value R4. The second value R2 is greater than or equal to the third value R3 and less than or equal to the fourth value R4.

In the phosphor wheel 100 illustrated in FIG. 3A, the wavelength conversion unit 20 is arranged in an annular shape centered on the rotation axis A1. The first detection unit 31 and the second detection unit 32 are arranged integrally with the annular wavelength conversion unit 20 along the annular wavelength conversion unit 20 so that they have different widths in the rotation direction of the phosphor wheel 100 but the same width in the radial direction.

As an example, the first detection unit 31 and the second detection unit 32 are formed connected to the second wavelength conversion region 22A. The first detection unit 31, the second detection unit 32, and the second wavelength conversion region 22A can be formed integrally. Alternatively, they may be formed separately.

The first detection unit 31 and the second detection unit 32 are arranged along the rotational direction of the phosphor wheel 100 and are formed to have different shapes. The first detection unit 31 and the second detection unit 32 have different lengths in the rotational direction. Here, as an example, the first detection unit 31 and the second detection unit 32 are formed on the inner circumferential side of the second wavelength conversion region 22A. Furthermore, the first detection unit 31 and the second detection unit 32 are spaced apart in the rotational direction and are formed to have different lengths in the rotational direction.

As illustrated in FIG. 4, the phosphor wheel 100 can be configured with a translucent substrate 10 and filter layers 11 on both sides of the substrate 10. The phosphor wheel 100 receives incident light L01 and L02 from its input surface and emits output light L1 and L2 from its output surface. The filter layer 11 has characteristics that allow it to transmit the incident light and reflect the light that has undergone wavelength conversion by the wavelength conversion unit 20. The filter layer 11 is, for example, a dielectric multilayer film. The wavelength conversion unit 20 is disposed on the filter layer 11 on the output surface side of the phosphor wheel 100. The input surface of the phosphor wheel 100 is the surface on which the wavelength conversion unit 20 is not disposed. This arrangement allows the incident light L01 and L02 to be suppressed from reflecting by the filter layer 11 and to pass through the translucent substrate 10 to reach the wavelength conversion unit 20. Furthermore, even if part of the light after wavelength conversion by the wavelength conversion section 20 is emitted toward the substrate 10, it can be reflected by the filter layer 11 toward the output surface and extracted.

The top and side surfaces of the wavelength conversion unit 20 and the side surfaces of the phosphor wheel 100 may be covered with a coating layer 12. The coating layer 12 increases the adhesive strength of the wavelength conversion unit 20 to the filter layer 11 and substrate 10. The coating layer 12 is made of a translucent material.

(Support member 40)
The support member 40 has a mandrel 41 and a support plate 42. The support plate 42 supports the mandrel 41 in a fixed orientation and position. The support member 40 supports the phosphor wheel 100 so that it can rotate freely.

(Drive unit 50)
The driving unit 50 generates torque around the rotation axis. The speed and direction of the rotation can be controlled externally. The driving unit 50 is, for example, an electric motor that operates when power is supplied. In the phosphor wheel device 200 illustrated in FIG. 2 , the rotation axis of the driving unit 50 overlaps with the axle 41 of the support member 40.

(Rotation detection unit 60)
The rotation detection unit 60 detects the speed and direction of rotation of the phosphor wheel 100. The rotation detection unit 60 includes, for example, a light-emitting unit 61 and a light-receiving unit 62. The light-emitting unit 61 includes a light-emitting element and emits light of a predetermined wavelength for detection (hereinafter referred to as detection light). The light-receiving unit 62 receives the detection light from the light-emitting unit 61 with a light-receiving element and outputs a signal corresponding to the amount of received light. The rotation detection unit 60 irradiates the detection light at a position on the rotating phosphor wheel 100 through which the detection unit 30 passes. The light-emitting unit 61 and the light-receiving unit 62 are disposed opposite each other across the phosphor wheel 100, as shown in FIG. 2, for example. This arrangement allows the light-receiving unit 62 to detect the detection light emitted from the light-emitting unit 61 and transmitted through the phosphor wheel 100.

Light emitted from the light-emitting unit 61 is incident on the phosphor wheel 100. When the phosphor wheel 100 rotates around the rotation axis A1, the trajectory of the light emitted from the light-emitting unit 61 on the phosphor wheel 100 describes a fifth circumference with a radius of fifth value R5 and centered on the rotation axis A1. The first detection unit 31 and the second detection unit 32 are located on this light trajectory. Therefore, the fifth value R5 is in the range from the third value R3 to the fourth value R4. The first detection unit 31 and the second detection unit 32 are arranged so that the lengths they pass along the fifth circumference are different. Here, different lengths includes when one of the lengths is zero. Note that the fifth value R5 only needs to be in the range from the third value R3 to the fourth value R4, and may be the same value as the second value R2.

Phosphor wheel device 200 uses rotation detection unit 60 to detect the speed and direction of rotation of phosphor wheel 100. Rotation detection unit 60 irradiates light emitted by light-emitting unit 61 onto rotating phosphor wheel 100, and receives the transmitted or reflected light with light-receiving unit 62. The speed and direction of rotation of phosphor wheel 100 can be detected from the change over time in the amount of light received by light-receiving unit 62.

In the rotation detection unit 60 shown in Figure 2, the transmittance of the first detection unit 31 and the second detection unit 32 for the wavelength of light emitted from the light-emitting unit 61 is lower than the transmittance of other areas on the same circumference. Therefore, when the phosphor wheel 100 rotates, the amount of light received by the light-receiving unit 62 is smaller when the first detection unit 31 and the second detection unit 32 are passing by, and is higher when they are not.

Figures 3A to 3C will be used to explain how the amount of light received by the light receiving unit 62 changes over time. In the phosphor wheel 100 illustrated in Figure 3A, the rotation detection unit 60 changes its detection state twice per rotation (one period T) of the phosphor wheel 100. One change is due to passage through the first detection unit 31, and the other change is due to passage through the second detection unit 32. Because the first detection unit 31 and the second detection unit 32 have different widths in the rotational direction of the phosphor wheel 100 on the same circumference, the length of time each detection state is maintained differs for the phosphor wheel 100 rotating at a constant speed. Note that the first detection unit 31 and the second detection unit 32 may be collectively referred to as the detection unit 30.

Figures 3B and 3C show examples of the change over time in the signal output by the rotation detection unit 60 when the phosphor wheel 100 rotates at a constant speed, corresponding to the change over time in the amount of light received by the light receiving section 62. When the amount of light received by the light receiving section 62 is relatively large, the signal corresponds to an H level, and when it is relatively small, the signal corresponds to an L level. In other words, the L level indicates that the detection light is incident on the detection section 30, and the H level indicates that the detection light is not incident on the detection section 30. Figure 3C shows the detection state when the rotation direction of the phosphor wheel 100 is reversed from the detection state in Figure 3B.

In both Figures 3B and 3C, the L level state is detected twice during one rotation of phosphor wheel 100 (during one cycle T). The second L level detection state is detected a time _T1 after the first L level detection state is detected. In the case of Figure 3B, the time ( _T2 time) from the end of the second L level detection state to the first L level detection state of the next cycle is detected is longer than _T1 time. Note that there only needs to be a sufficient time difference between _T1 time and _T2 time so that the difference between them can be clearly detected, and _T2 time may be shorter than _T1 time.

In Figure 3B, the time during which the second L level detection state is maintained is longer than the time during which the first L level detection state is maintained. On the other hand, in Figure 3C, the time during which the second L level detection state is maintained is shorter than the time during which the first L level detection state is maintained. In this way, phosphor wheel 100 can detect the direction of rotation from the order of the length of the L level detection state. It is also possible to detect the direction of rotation from the order of the length of the H level detection state.

In the light-emitting module 1000, one or more first light-emitting devices 410 emit light having a first wavelength as its peak wavelength. The emitted light is irradiated onto the wavelength conversion section 20 of the phosphor wheel device 200. The irradiated light is wavelength-converted by the wavelength conversion section 20, and the phosphor wheel device 200 outputs the first light. The rotation detection unit 60 detects the speed and direction of rotation of the phosphor wheel 100. This makes it possible to monitor the speed and direction of rotation of the phosphor wheel 100 and determine if it is malfunctioning relative to expected normal operation.

Light-emitting module 1000 may include one or more second light-emitting devices 420 that emit light having a peak wavelength at a second wavelength different from the first wavelength. The emitted light is irradiated onto wavelength conversion section 20 of phosphor wheel device 200. The irradiated light is wavelength-converted by wavelength conversion section 20, and phosphor wheel device 200 outputs second light. However, wavelength conversion section 20 has first wavelength conversion region 21A that is irradiated with light emitted from one or more first light-emitting devices 410, and second wavelength conversion region 22A that is irradiated with light emitted from one or more second light-emitting devices 420. Therefore, the light emitted from one or more first light-emitting devices 410 and the light emitted from one or more second light-emitting devices 420 can be wavelength-converted separately.

(Optical components)
An optical element is an element that controls incident light by refracting or reflecting the light, and emits the light afterward. Examples of optical elements include a condenser lens, a diffusion element, a collimating lens, and a mirror.

(condensing lens)
The first condenser lens 511, the second condenser lens 521, and the third condenser lens 531 condense the incident light and emit the condensed light. Each of these condenser lenses may be a single lens or may be formed from multiple compound lenses.
(Diffusion member)
The diffusing member 300 diffuses incident light and emits it. The diffusing member 300 diffuses light that is concentrated in a specific direction to make the light uniform. The diffusing member 300 can be formed by incorporating a diffusing material into a base material. The diffusing member 300 can also be formed by providing irregularities on the front and back surfaces. By making the light uniform, the diffusing member 300 makes the light suitable for the purpose of use.
(collimating lens)
The first collimating lens 512, the second collimating lens 522, and the third collimating lens 532 convert incident light into parallel light and emit the parallel light. Each of the collimating lenses may be a single lens or a compound lens.
(mirror)
The first mirror 513, the second mirror 523, and the third mirror 533 reflect a part of the incident light and transmit a part of the incident light. Each of the mirrors may be, for example, a dichroic mirror.

The optical members are arranged in the optical path from each light emitting device to the light outlet 700 .
The first condensing lens 511 is disposed at a position where it condenses light irradiated from the first light-emitting device 410 and emits the light toward the first wavelength conversion region 21A. The second condensing lens 521 is disposed at a position where it condenses light irradiated from the second light-emitting device 420 and emits the light toward the second wavelength conversion region 22A. The third condensing lens 531 is disposed at a position where it condenses light irradiated from the third light-emitting device 430 and emits the light toward the diffusion member 300.
The light diffused by the diffusing member 300 is emitted to the third collimating lens 532 .

The first collimating lens 512 is disposed at a position where it outputs the light wavelength-converted in the first wavelength conversion region 21A as parallel light toward the first mirror 513. The second collimating lens 522 is disposed at a position where it outputs the light wavelength-converted in the second wavelength conversion region 22A as parallel light toward the second mirror 523. The third collimating lens 532 is disposed at a position where it outputs the light diffused by the diffusing member 300 as parallel light toward the third mirror 533.
The first mirror 513 is positioned to reflect the first light that has been wavelength-converted and converted into parallel light. The second mirror 523 is positioned to reflect the second light that has been wavelength-converted and converted into parallel light and to transmit the first light. The third mirror 533 is positioned to reflect the third light that has been diffused and converted into parallel light and to transmit the first light and the second light.

(Second light-emitting device 420, third light-emitting device 430)
The above-mentioned description of the first light emitting device 410 is common to the second light emitting device 420 and the third light emitting device 430 .
When light-emitting module 1000 includes one or more first light-emitting devices 410 and one or more second light-emitting devices 420, one or more first light-emitting devices 410 can include a plurality of first semiconductor laser elements, and one or more second light-emitting devices 420 can include a plurality of second semiconductor laser elements. The first semiconductor laser elements and the second semiconductor laser elements may be the same or different.

If the light-emitting module 1000 further includes one or more third light-emitting devices 430, the one or more third light-emitting devices 430 may be configured to include multiple third semiconductor laser elements. The first semiconductor laser element, second semiconductor laser element, and third semiconductor laser element may be the same or different from each other.

Next, the light emitting module 1000 illustrated in FIG. 1 will be described with a focus on the path of light.
First light-emitting device 410 emits first light having a first wavelength as a peak wavelength. The emitted first light is condensed by first condensing lens 511 onto first wavelength conversion region 21A of phosphor wheel 100. The condensed light is wavelength-converted by the phosphor in first wavelength conversion region 21A, and the wavelength-converted first light is emitted from phosphor wheel device 200. Furthermore, the wavelength-converted first light is converted into parallel light L1P by first collimating lens 512. Parallel light L1P is reflected by first mirror 513, and the reflected light is L1P2 that travels in the direction of light extraction outlet 700.

The phosphor wheel 100 is positioned closer to the first collimating lens 512 than the first condenser lens 511. The phosphor wheel 100 is preferably positioned near the first collimating lens 512. Because wavelength-converted light is emitted from the wavelength conversion unit 20 over a wide angular range, light loss can be reduced by placing the wavelength conversion unit 20 closer to the first collimating lens 512. Furthermore, when collimating the same amount of light, the lens surface area of the first collimating lens 512 can be designed to be smaller.

The second light-emitting device 420 emits second light having a second wavelength as its peak wavelength. The emitted second light is focused by the second focusing lens 521 onto the second wavelength conversion region 22A of the phosphor wheel 100. The focused light is wavelength-converted by the phosphor in the second wavelength conversion region 22A, and the wavelength-converted second light is emitted from the phosphor wheel device 200. The wavelength-converted second light is then converted into parallel light L2P by the second collimating lens 522. The parallel light L2P is reflected by the second mirror 523, and the reflected light is L2P2 that travels in the direction of the light extraction outlet 700.

The third light-emitting device 430 emits third light having a third wavelength as a peak wavelength. The emitted third light is condensed onto the diffusing member 300 by the third condensing lens 531. The diffusing member 300 diffuses the condensed light and emits it. The diffused third light is converted into parallel light L3P by the third collimating lens 532. The parallel light L3P is reflected by the third mirror 533, and the reflected light is L3P2 that travels in the direction of the light extraction port 700.
1 are arranged so that the optical axes of the lights L1P2, L2P2, and L3P2 traveling in the direction of the light extraction port 700 coincide with each other. Therefore, the parallel lights L1P, L2P, and L3P can be extracted from the light extraction port 700 as separate lights or combined lights traveling along the same axis.

1 illustrates an example in which there is only one light extraction outlet 700. However, as shown in FIG. 10 , for example, a first light extraction outlet 710, a second light extraction outlet 720, and a third light extraction outlet 730 may be provided in the housing 600A to extract the individual light beams and the combined light beams separately, as shown in the light-emitting module 1000A of FIG. 10 . For example, the first mirror 513A may reflect 50% of the first light beam L1P that has been wavelength-converted into collimated light and transmit 50%, so that the light beam L1P1 that passes through the first mirror 513A can be extracted from the first light extraction outlet 710. Similarly, the second mirror 523A may reflect 50% of the second light beam L2P that has been wavelength-converted into collimated light and transmit 50%, so that the light beam L2P1 that passes through the second mirror 523A can be extracted from the second light extraction outlet 720. Furthermore, the third mirror 533A reflects 50% of the third light L3P that has been diffused and turned into parallel light, and transmits 50% of the third light L3P, so that light L3P1 that passes through the third mirror 533A can be extracted from the third light extraction port 730. Furthermore, the separate light or the combined light can be extracted from the light extraction port 700.
Furthermore, in FIGS. 1 and 10, a heat sink for removing heat may be provided behind the first light emitting device 410, the second light emitting device 420, and the third light emitting device 430.

Next, modified examples 1 to 5 of each configuration will be described with reference to FIGS. 5A to 9C.
(Variation 1)
5A , the wavelength conversion unit 20 is provided in an annular shape around the rotation axis A1. The first detection unit 31A and the second detection unit 32A are provided integrally with the annular wavelength conversion unit 20 along the phosphor wheel 101 such that the first detection unit 31A and the second detection unit 32A have different widths in the radial direction of the phosphor wheel 101 but the same width in the rotation direction.
5B and 5C show examples of the time change in the signal output by the rotation detection unit 60 when the phosphor wheel 101 rotates at a constant speed. While FIGS. 3B and 3C utilize the difference in the time at which the L level is detected, FIGS. 5B and 5C utilize the difference in the amount of light detected by the light receiving unit 62. That is, the amount of light received by the light receiving unit 62 when the detection light passes through the first detection unit 31A is different from the amount of light received by the light receiving unit 62 when the detection light passes through the second detection unit 32A. For example, one of the first detection unit 31A and the second detection unit 32A is at the M1 level, while the other is at the L level, which is lower than the M1 level. This is because the second detection unit 32A, which has a larger radial width than the first detection unit 31A, blocks more light. For example, with respect to the area irradiated with the detection light, only a portion of the detection light is blocked by the first detection unit 31A, while the entire detection light is blocked by the second detection unit 32A.

(Variation 2)
In the phosphor wheel 102 shown in Fig. 6A, the wavelength conversion unit 20 is provided in an annular shape centered on the rotation axis A1. At least one of the first detection unit 31B and the second detection unit 32B has a width in the rotation direction of the phosphor wheel 102 that is not constant in the radial direction. Here, "the width in the rotation direction is not constant" means that the central angle around the rotation axis A1 at both ends in the rotation direction is not constant. The second detection unit 32B of the phosphor wheel 102 has a central angle that increases as the radius increases, and the width in the rotation direction increases in the direction in which the radius increases.
The first detector 31B and the second detector 32B are formed integrally with the wavelength converter 20 along the annular wavelength converter 20. The first detector 31B and the second detector 32B have the same width in the radial direction except for the ends in the rotation direction. The ends in the rotation direction of the second detector 32B have different inclinations relative to the radial direction. The first detector 31B and the second detector 32B are formed integrally with the wavelength converter 20 along the annular wavelength converter 20.

Figures 6B and 6C show examples of the time change in the signal output by the rotation detection unit 60 when phosphor wheels 102 rotate at a constant speed, with the phosphor wheels 102 rotating in opposite directions. As with Figures 3B and 3C, the direction of rotation can also be detected from the detection results in Figures 6B and 6C.

(Variation 3)
In a time-division light source, light of multiple wavelengths output from a phosphor wheel device may be extracted and used in a time-division manner. In such a case, one or more phosphors included in wavelength conversion unit 20 are provided in a partitioned manner in the rotation direction of annular wavelength conversion unit 20. Phosphor wheel 103 shown in FIG. 7 has phosphors 21B, 22B, and 23B provided in a partitioned manner in the rotation direction.
The first detector 31C and the second detector 32C are provided integrally with the annular wavelength converter 20 along the annular wavelength converter 20 so that they have different widths in the rotation direction of the phosphor wheel 103 but the same width in the radial direction. The temporal change in the signal output by the rotation detection unit 60 can be similar to that shown in Figures 3B and 3C. Note that if the first detector 31C and the second detector 32C have different optical absorptances at the wavelength of light emitted by the light-emitting unit 61 of the rotation detection unit 60, the same can be said as in Figures 5B and 5C.

(Variation 4)
8A, like phosphor wheel 103, phosphors 21B, 22B, and 23B are partitioned in the rotational direction. First detection unit 31D, second detection unit 32D, and third detection unit 33D are provided integrally with wavelength conversion unit 20 along the annular wavelength conversion unit 20, and have the same width in the radial direction and the same width in the rotational direction. Meanwhile, first detection unit 31D, second detection unit 32D, and third detection unit 33D each have a different light absorption rate for the detection light.
8B and 8C show examples of the time change in the signal output by the rotation detection unit 60 when the phosphor wheel 104 rotates at a constant speed. As shown in FIGS. 8B and 8C, whether the detection light is passing through the first detection unit 31D, the second detection unit 32D, or the third detection unit 33D can be determined from the difference in the detection state levels. In FIG. 8B, which shows rotation at a D1 rotation, different levels of L, M3, and M2 appear in sequence. In FIG. 8C, which shows rotation at a D2 rotation, L, M2, and M3 appear in sequence. In this way, the direction of rotation can be detected from the order in which the levels of L, M2, and M3 are detected.

(Variation 5)
The rotation detection unit 60 may detect rotation using reflected light. In the example shown in Fig. 9A, the light-emitting unit 61 emits light that irradiates the rotating phosphor wheel 105, and the reflected light is received by the light-receiving unit 62. For this reason, the first detection unit 31E and the second detection unit 32E have light-reflective surfaces, and the light-emitting unit 61 and the light-receiving unit 62 of the rotation detection unit 60 are arranged on the same side of the phosphor wheel 105.
9B and 9C show examples of the change over time in the signal output by the rotation detection unit 60 when the phosphor wheel 105 rotates at a constant speed. In the cases of FIGS. 3B and 3C, the amount of received light is at L level when the detection light passes through the detection unit 30 and at H level when the detection light does not pass through the detection unit 30, but in the cases of FIGS. 9B and 9C, the amount of received light is at H level when the detection light passes through the detection unit 30 and at L level when the detection light does not pass through the detection unit 30. In this case as well, the direction of rotation can be detected based on the same principle.

The first detector and the second detector may include one or more phosphors contained in the one or more phosphors of the wavelength converter.
In the embodiment and the modified example, the detecting units may be formed integrally with the adjacent wavelength converting units using the same material along the annular wavelength converting unit, i.e., the detecting units may be provided on the inside or outside of the annular wavelength converting unit like protrusions of the wavelength converting unit.

For example, in the phosphor wheel 100 of the embodiment, the first detection unit 31 and the second detection unit 32 can be formed from the same material as the second wavelength conversion region 22A of the wavelength conversion unit 20, like protrusions of the second wavelength conversion region 22A. In this way, the first detection unit 31 and the second detection unit 32 can be formed without increasing the type of material of the phosphor wheel 100. Furthermore, for example, when the wavelength conversion unit 20 is formed by screen printing or the like using a mask, the first detection unit 31 and the second detection unit 32 can be formed simultaneously without increasing the number of processes.
The detection section 30 may be formed separately from the wavelength conversion section 20 using the same material, or may be formed integrally with the wavelength conversion section 20 using a material different from that of the wavelength conversion section 20 .

Also, the first detection unit and the second detection unit may be configured so that the first detection unit contains a first phosphor and the second detection unit contains a second phosphor different from the first phosphor. By using different phosphors in this way, the light absorption rates of the first detection unit and the second detection unit can be made different. As a result, the direction of rotation can be detected not only from the order of long and short detection states, but also from the order of detection states with different levels, without increasing the amount of material in the phosphor wheel.

In the explanation so far, the first wavelength and the second wavelength have been described as being different. However, the first wavelength and the second wavelength may be the same. For example, the first light-emitting device 410 and the second light-emitting device 420 may emit blue light, and the third light-emitting device 430 may emit purple light. In this case, semiconductor laser elements that emit blue light may be used as the light-emitting elements of the first light-emitting device 410 and the second light-emitting device 420, and a semiconductor laser element that emits purple light may be used as the light-emitting element of the third light-emitting device 430.

Although the embodiments of the present invention have been described above, the phosphor wheel device and light-emitting module of the present invention are not strictly limited to those described in the embodiments. In other words, the present invention can be realized without being limited to the external shapes and structures of the phosphor wheel device and light-emitting module disclosed in the embodiments. Furthermore, the present invention can be applied without necessarily including all necessary and sufficient components. For example, if the claims do not recite some of the components of a light-emitting module disclosed in the embodiments, the claims allow for the design freedom of those components by those skilled in the art, such as substitution, omission, modification of shape, and change of materials, and specify that the invention described in the claims applies.

REFERENCE SIGNS LIST 10 Substrate 20 Wavelength conversion section 21A First wavelength conversion region 22A Second wavelength conversion region 30 Detection section 31 First detection section 32 Second detection section 40 Support member 41 Core 42 Support plate 50 Drive section 60 Rotation detection unit 61 Light emitting section 62 Light receiving section 100 Phosphor wheel 200 Phosphor wheel device 300 Diffusion member 410 First light emitting device 511 First condenser lens 512 First collimator lens 513 First mirror 600 Housing 700 Light extraction outlet 710 First light extraction outlet 1000 Light emitting module

Claims (12)

a phosphor wheel including a substrate, a wavelength conversion unit including one or more phosphors that convert the wavelength of light and provided on the substrate, and a first detection unit and a second detection unit provided on the substrate;
a support member that rotatably supports the phosphor wheel;
a driving unit that rotates the phosphor wheel around a rotation axis of the phosphor wheel;
Equipped with
the wavelength converting portion is arranged so as to pass through a first circumference having a radius of a first value and centered on the rotation axis,
the first detection unit and the second detection unit are arranged so as to pass through a second circumference having a center on the rotation axis and a radius of a second value different from the first value,
The first and second detection units are arranged in a phosphor wheel device such that, when the value of the smallest radius of a circumference centered on the rotation axis and through which at least one of the first detection unit and the second detection unit passes is a third value, and the value of the largest radius of a circumference centered on the rotation axis and through which at least one of the first detection unit and the second detection unit passes is a fourth value, the length of the first detection unit passing on the circumference and the length of the second detection unit passing on the circumference are different on a fifth circumference centered on the rotation axis and having a radius of between the third value and the fourth value. The phosphor wheel device according to claim 1, wherein the first detection unit and the second detection unit have different widths in the rotational direction of the phosphor wheel on the same circumference. the wavelength converting portion is provided on the substrate in an annular shape,
The phosphor wheel device of claim 2, wherein the first detection unit and the second detection unit have the same width in the radial direction of the phosphor wheel and are provided integrally with or separately from the wavelength conversion unit along the annular wavelength conversion unit. The phosphor wheel device according to claim 1, wherein the first detection unit and the second detection unit have different widths in the radial direction of the phosphor wheel. The phosphor wheel device according to claim 1, wherein the width of at least one of the first detection unit and the second detection unit in the rotational direction of the phosphor wheel is not constant in the radial direction of the phosphor wheel. The phosphor wheel device according to claim 1 , wherein the first detection unit and the second detection unit include one or more phosphors contained in the one or more phosphors. the first detection unit includes a first fluorescent material;
The phosphor wheel device according to claim 1 , wherein the second detection unit includes a second phosphor different from the first phosphor. The phosphor wheel device according to claim 1 , wherein the first detection unit and the second detection unit are provided on a surface of the light-transmitting substrate. The phosphor wheel device according to claim 1 ;
one or more first light emitting devices that emit light having a first wavelength as a peak wavelength to the wavelength converting unit;
a rotation detection unit including: a light-emitting unit that emits detection light to a position through which the first detection unit and the second detection unit pass as the phosphor wheel rotates; and a light-receiving unit that receives the detection light;
A light emitting module comprising: further comprising one or more second light emitting devices configured to emit light having a second wavelength different from the first wavelength to the wavelength converting portion;
The light emitting module according to claim 9, wherein the wavelength conversion section has a first wavelength conversion region that is irradiated with light emitted from the one or more first light emitting devices, and a second wavelength conversion region that is irradiated with light emitted from the one or more second light emitting devices. The light emitting module according to claim 10 , wherein the first wavelength conversion region and the second wavelength conversion region are annular regions that do not overlap each other. the one or more first light-emitting devices include a plurality of first semiconductor laser elements;
12. The light-emitting module according to claim 10 , wherein the one or more second light-emitting devices include a plurality of second semiconductor laser elements.