Light source system

Abstract

The present invention enables dimming and toning even when a solid light source, which emits seed light, is not used. A first wavelength conversion unit (3) includes a first wavelength conversion element which can generate first spontaneous emission light of a plurality of wavelengths that are of longer wavelengths than first excitation light (P1). A second wavelength conversion unit (5) includes a second wavelength conversion element that can generate second spontaneous emission light of a plurality of wavelengths that are of longer wavelengths than second excitation light (P2). An optical member (6) is disposed between the second wavelength conversion unit (5) and the first wavelength conversion unit (3). The optical member (6) includes a plurality of filter units (60). A motor (7) rotates the optical member (6). A control unit (8) controls the motor (7) and a second solid light source (4). In the optical member (6), the plurality of filter units (60) are aligned on the circumference of the center around the rotational central axis (A6) of the optical member (6). Each of a plurality of wavelength bands includes the wavelengths of second spontaneous emission light of at least one of the plurality of wavelengths of the second spontaneous emission light generated in the second wavelength conversion unit (5).

Description

[Technical field]

[0001] The present disclosure relates generally to light source systems, and more particularly to light source systems that utilize excitation light. [Background technology]

[0002] Patent Document 1 discloses a light emitting device including an optical fiber, a first light source section, and a second light source section as a light source device. The optical fiber includes a wavelength conversion material (wavelength conversion element) that is excited by excitation light and generates spontaneous emission light having a longer wavelength than the excitation light. The first light source section inputs excitation light into a light incident section of the optical fiber. The second light source section inputs seed light into a light incident section of the optical fiber for generating stimulated emission light from the wavelength conversion material excited by the excitation light or the amplified spontaneous emission light. The first light source section includes a laser light source (first solid-state light source). The second light source section includes, for example, a seed light source (semiconductor laser) that emits green light, a seed light source (semiconductor laser) that emits orange light, and a seed light source (semiconductor laser) that emits red light.

[0003] The light emitting device disclosed in Patent Document 1 further includes an adjustment unit that adjusts the intensity of each of the multiple seed light beams emitted from the multiple seed light sources.

[0004] The light source device disclosed in Patent Document 1 requires a solid-state light source such as a semiconductor laser that emits seed light, but in some cases, semiconductor lasers that emit light of a wavelength corresponding to the wavelength of the amplified spontaneous emission light of the wavelength conversion material are not manufactured or sold, making it difficult to obtain seed light of the desired wavelength. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] International Publication No. 2021 / 014853 Summary of the Invention

[0006] An object of the present disclosure is to provide a light source system capable of adjusting brightness and color without using a solid-state light source that emits seed light.

[0007] A light source system according to an embodiment of the present disclosure includes a first solid-state light source, a first wavelength conversion unit, a second solid-state light source, a second wavelength conversion unit, an optical member, a motor, and a control unit. The first solid-state light source emits a first excitation light. The first wavelength conversion unit is an optical fiber including a first wavelength conversion element that is excited by the first excitation light and capable of generating first spontaneous emission light of a plurality of wavelengths longer than the first excitation light, and that is excitable by a first amplified spontaneous emission light. The second solid-state light source emits a second excitation light. The second wavelength conversion unit includes a second wavelength conversion element that is excited by the second excitation light and capable of generating second spontaneous emission light of a plurality of wavelengths longer than the second excitation light, and that is excitable by a second amplified spontaneous emission light. The optical member is disposed between the second wavelength conversion unit and the first wavelength conversion unit. The optical member has a plurality of filter units corresponding to light of a plurality of wavelength ranges. The motor rotates the optical member. The control unit controls the motor and the second solid-state light source. In the optical member, the plurality of filter sections are arranged on a circumference centered on a central axis of rotation of the optical member, and each of the plurality of wavelength ranges includes at least one wavelength of second spontaneous emission light among the plurality of wavelengths of second spontaneous emission light generated in the second wavelength conversion section. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a configuration diagram of a light source system according to the first embodiment. [Diagram 2] FIG. 2 is a cross-sectional view of an optical fiber constituting a first wavelength conversion unit in the light source system. [Diagram 3] FIG. 3 is a cross-sectional view of an optical fiber constituting a second wavelength conversion unit in the light source system. [Figure 4]Fig. 4A is a plan view of a member including an optical member and a motor in the light source system of the above, Fig. 4B is a cross-sectional view of the member including an optical member and a motor in the light source system of the above, taken along line XX in Fig. 4A, Fig. 4C is a cross-sectional view of the member including an optical member and a motor in the light source system of the above, taken along line YY in Fig. 4A. [Diagram 5] FIG. 5 is a diagram illustrating the operation of the light source system. [Figure 6] FIG. 6 is a configuration diagram of a light source system according to the second embodiment. [Figure 7] Fig. 7A is a plan view of a member including an optical member and a motor in the light source system of the above, Fig. 7B is a cross-sectional view of the member including an optical member and a motor in the light source system of the above, taken along line XX in Fig. 7A, Fig. 7C is a cross-sectional view of the member including an optical member and a motor in the light source system of the above, taken along line YY in Fig. 7A. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] The drawings described in the following embodiments 1 and 2 are schematic drawings, and the size and thickness ratios of the components in the drawings do not necessarily reflect the actual dimensional ratios.

[0010] (Embodiment 1) A light source system 1 according to the first embodiment will be described below with reference to FIGS.

[0011] (1) Overview As shown in FIG. 1, the light source system 1 includes a first solid-state light source 2, a first wavelength conversion unit 3, a second solid-state light source 4, a second wavelength conversion unit 5, an optical member 6, a motor 7, and a control unit 8. The first solid-state light source 2 emits a first excitation light P1. The first wavelength conversion unit 3 includes a first wavelength conversion element (e.g., Pr 3+The first wavelength conversion element is capable of being excited by the first excitation light P1 to generate first spontaneous emission light of a plurality of wavelengths longer than the first excitation light P1, and is also capable of being excited by the first amplified spontaneous emission light. The second solid-state light source 4 emits the second excitation light P2. The second wavelength conversion unit 5 is an optical fiber including a second wavelength conversion element (for example, Pr 3+ ). The second wavelength conversion element is excited by the second excitation light P2 and can generate second spontaneous emission light of a plurality of wavelengths longer than the second excitation light P2, and can be excited by the second amplified spontaneous emission light. The optical member 6 is disposed between the second wavelength conversion section 5 and the first wavelength conversion section 3. The optical member 6 has a plurality of filter sections 60 corresponding to light of a plurality of wavelength ranges. The plurality of filter sections 60 include a plurality of transmission sections 61 to 64 that transmit light of a plurality of wavelength ranges. The motor 7 rotates the optical member 6. The control section 8 controls the motor 7 and the second solid-state light source 4. In the optical member 6, the plurality of filter sections 60 are arranged on a circumference centered on the rotation central axis A6 of the optical member 6. Each of the plurality of wavelength ranges includes the wavelength of the second spontaneous emission light of at least one wavelength among the plurality of wavelengths of the second spontaneous emission light generated in the second wavelength conversion section 5. The light source system 1 inputs multiple types of light having the same wavelengths as the second spontaneous emission lights of multiple wavelengths generated in the second wavelength conversion unit 5 into the first wavelength conversion unit 3 as seed light for generating stimulated emission light from the first wavelength conversion element excited by the first excitation light P1 or the amplified spontaneous emission light. In Fig. 1, the optical paths of four types of seed light P21, P22, P23, and P24 out of the multiple types of seed light are diagrammatically illustrated.

[0012] The emitted light of the light source system 1 is light emitted from the first wavelength conversion section 3. In the light source system 1, for example, light including a first excitation light P1 and multiple types of stimulated emission light is emitted from the first wavelength conversion section 3. In Fig. 1, four types of stimulated emission light P11, P12, P13, and P14 among the multiple types of stimulated emission light are diagrammatically illustrated.

[0013] The light source system 1 can be applied to, for example, lighting applications. Examples of lighting applications include, but are not limited to, indoor downlights, lighting systems for cold storage warehouses, lighting systems for outdoor tennis courts, lighting systems for tunnels, lighting systems for attracting fish on fishing boats, and vehicle headlights. The light source unit can also be applied to, for example, projection systems including projectors, without being limited to lighting applications.

[0014] (2) Light source system configuration As shown in Fig. 1, the light source system 1 includes a first solid-state light source 2, a first wavelength conversion unit 3, a second solid-state light source 4, a second wavelength conversion unit 5, an optical member 6, a motor 7, and a control unit 8. The light source system 1 further includes a first drive circuit 9, a second drive circuit 10, and a motor drive circuit 11. The first drive circuit 9 drives the first solid-state light source 2. The second drive circuit 10 drives the second solid-state light source 4. The motor drive circuit 11 drives the motor 7. The light source system 1 further includes an optical element 12. The optical element 12 is, for example, a dichroic mirror.

[0015] (2.1) First solid-state light source The first solid-state light source 2 emits a first excitation light P1. The first solid-state light source 2 emits the first excitation light P1 for exciting a first wavelength conversion element included in the first wavelength conversion section 3. The first excitation light P1 emitted from the first solid-state light source 2 is incident on the first wavelength conversion section 3. More specifically, the first excitation light P1 emitted from the first solid-state light source 2 is incident on the first wavelength conversion section 3.

[0016] The first solid-state light source 2 is a light source that emits quasi-monochromatic light. Quasi-monochromatic light is light included in a narrow wavelength range (for example, 10 nm). The first solid-state light source 2 includes, for example, a laser light source. The laser light source emits laser light. The first excitation light P1 (laser light emitted from the laser light source) emitted from the first solid-state light source 2 is incident on the first wavelength conversion unit 3. The laser light source is, for example, a semiconductor laser that emits blue laser light. In this case, the wavelength of the first excitation light P1 is, for example, 440 nm to 450 nm.

[0017] (2.2) First wavelength conversion section The first wavelength conversion unit 3 includes a first wavelength conversion element (e.g., Pr 3+ ) is an optical fiber including the first wavelength conversion element. Therefore, the first wavelength conversion unit 3 has flexibility. The first wavelength conversion element is excited by the first excitation light P1 and can generate first spontaneous emission lights of multiple wavelengths longer than the first excitation light P1, and can be excited by the first amplified spontaneous emission light.

[0018] 2, the first wavelength conversion section 3 has a core 33, a clad 34, and a covering section 35. The clad 34 covers the outer peripheral surface of the core 33. The covering section 35 covers the outer peripheral surface of the clad 34. The cross-sectional shape of the core 33 perpendicular to the optical axis direction is circular. The clad 34 is disposed coaxially with the core 33.

[0019] The core 33 includes a light-transmitting material and a first wavelength converting element. In other words, the core 33 contains the first wavelength converting element. The concentration of the first wavelength converting element in the core 33 may be substantially uniform over the entire length of the core 33, or may not be uniform. The diameter of the core 33 is, for example, 25 μm to 500 μm. The length of the first wavelength converting section 3 is, for example, 3 m to 10 m. The length of the first wavelength converting section 3 is preferably longer as the concentration of the first wavelength converting element in the first wavelength converting section 3 is lower. The numerical aperture of the optical fiber constituting the first wavelength converting section 3 is, for example, 0.22.

[0020] The refractive index of the core 33 is approximately the same as the refractive index of the above-mentioned light-transmitting material that is the main component of the core 33 .

[0021] The light-transmitting material may be, for example, a fluoride, an oxide, or a nitride. The fluoride may be, for example, a fluoride glass. The oxide may be, for example, silicon oxide, quartz, or the like.

[0022] The first wavelength conversion element is a rare earth element. Here, the first wavelength conversion element includes, for example, an element selected from the group consisting of Pr, Tb, Ho, Dy, Er, Eu, Nd, and Mn. The first wavelength conversion element is contained in the core 33 as ions of a rare earth element, and is, for example, an ion of Pr (Pr 3+ ) is contained in the second wavelength conversion unit 5. The first wavelength conversion element may be excited by the first excitation light P1, or may be excited by light amplified using spontaneous emission light emitted from another first wavelength conversion element as internal seed light, that is, amplified spontaneous emission (ASE). Through such excitation, the first wavelength conversion element emits ASE specific to the element of the first wavelength conversion element, and also generates multiple types of stimulated emission light having the same wavelengths as the wavelengths of the multiple types of seed light P21 to P24 from the second wavelength conversion unit 5, and combines these and emits them as stimulated emission light P11 to P14. The wavelengths of the ASE and the seed light P21 to P24 are longer than the wavelength of the first excitation light P1 (for example, 440 nm to 450 nm). The wavelengths of the multiple types of seed light P21 to P24 will be described in the section "(2.4) Second Wavelength Conversion Unit".

[0023] The refractive index of the cladding 34 is smaller than the refractive index of the core 33. The cladding 34 does not include the first wavelength converting element that the core 33 contains.

[0024] The material of the covering portion 35 is, for example, resin. The outer diameter of the covering portion 35 is, for example, 1 mm or less.

[0025] The first wavelength conversion section 3 has a light incident section 31 and a light emitting section 32. In the first wavelength conversion section 3, the light incident section 31 is configured by a first end surface 331 of the core 33, and the light emitting section 32 is configured by a second end surface 332 of the core 33.

[0026] In the first wavelength conversion unit 3, the first excitation light P1 from the first solid-state light source 2 and the multiple types of seed light P21 to P24 from the second wavelength conversion unit 5 are incident on the light incident unit 31. In the light source system 1, the first excitation light P1 from the first solid-state light source 2 is reflected by the optical element 12 and incident on the light incident unit 31 of the first wavelength conversion unit 3. In addition, the multiple types of seed light P21 to P24 from the second wavelength conversion unit 5 are incident on the light incident unit 31 of the first wavelength conversion unit 3 via the optical element 12. The stimulated emission light P11 to P14 including ASE are emitted from the light emission unit 32 of the first wavelength conversion unit 3. The first excitation light P1 and the second excitation light P2 are also emitted from the first wavelength conversion unit 3.

[0027] (2.3)Second solid-state light source The second solid-state light source 4 emits a second excitation light P2. The second solid-state light source 4 emits the second excitation light P2 for exciting the second wavelength conversion element included in the second wavelength conversion section 5. The second excitation light P2 emitted from the second solid-state light source 4 is incident on the second wavelength conversion section 5. More specifically, the second excitation light P2 emitted from the second solid-state light source 4 is incident on the second wavelength conversion section 5. The second excitation light P2 emitted from the second solid-state light source 4 is directly incident on the second wavelength conversion section 5, but is not limited thereto, and may be incident via an optical coupling member such as a lens.

[0028] The second solid-state light source 4 is a light source that emits quasi-monochromatic light. Quasi-monochromatic light is light that is included in a narrow wavelength range (for example, 10 nm). The second solid-state light source 4 includes, for example, a laser light source. The laser light source emits laser light. The second excitation light P2 (laser light emitted from the laser light source) emitted from the second solid-state light source 4 is incident on the second wavelength conversion unit 5. The laser light source is, for example, a semiconductor laser that emits blue laser light. In this case, the wavelength of the second excitation light P2 is, for example, 440 nm to 450 nm.

[0029] (2.4) Second wavelength conversion section The second wavelength converting portion 5 is a second wavelength converting element (for example, Pr 3+). In the light source system 1, the second wavelength conversion unit 5 is an optical fiber including a second wavelength conversion element. The second wavelength conversion element is excited by the second excitation light P2 and can generate second spontaneous emission light of a plurality of wavelengths longer than the second excitation light P2, and can be excited by the second amplified spontaneous emission light.

[0030] 3, the second wavelength converting section 5 has a core 53, a clad 54, and a covering section 55. The clad 54 covers the outer peripheral surface of the core 53. The covering section 55 covers the outer peripheral surface of the clad 54. The cross-sectional shape of the core 53 perpendicular to the optical axis direction is circular. The clad 54 is disposed coaxially with the core 53.

[0031] The core 53 includes a light-transmitting material and a second wavelength converting element. In other words, the core 53 contains the second wavelength converting element. The concentration of the second wavelength converting element in the core 53 may be approximately uniform over the entire length of the core 53, or may not be uniform. The diameter of the core 53 is, for example, 25 μm to 500 μm. The length of the second wavelength converting section 5 is, for example, 3 m to 10 m. The length of the second wavelength converting section 5 is preferably longer as the concentration of the second wavelength converting element in the second wavelength converting section 5 is lower. The numerical aperture of the optical fiber constituting the second wavelength converting section 5 is, for example, 0.22.

[0032] The refractive index of the core 53 is approximately the same as the refractive index of the above-mentioned light-transmitting material that is the main component of the core 53 .

[0033] The light-transmitting material may be, for example, a fluoride, an oxide, or a nitride. The fluoride may be, for example, a fluoride glass. The oxide may be, for example, silicon oxide, quartz, or the like.

[0034] The second wavelength conversion element is a rare earth element. Here, the second wavelength conversion element includes an element selected from the group consisting of Pr, Tb, Ho, Dy, Er, Eu, Nd, and Mn. The second wavelength conversion element is contained in the core 53 as ions of a rare earth element. The second wavelength conversion element is an element of the same type as the first wavelength conversion element, and is, for example, an ion of Pr (Pr3+ ) is contained in the core 53. The second wavelength conversion element may be excited by the second excitation light P2, or may be excited by light amplified using spontaneous emission light emitted from a second wavelength conversion element other than itself as internal seed light, that is, amplified spontaneous emission (ASE). Through such excitation, the second wavelength conversion element emits ASE specific to the element of the second wavelength conversion element. The wavelengths of the ASE and the seed lights P21 to P24 are longer than the wavelength of the second excitation light P2 (for example, 440 nm to 450 nm).

[0035] The refractive index of the cladding 54 is smaller than the refractive index of the core 53. The cladding 54 does not include the second wavelength converting element that the core 53 contains.

[0036] The material of the covering portion 55 is, for example, resin. The outer diameter of the covering portion 55 is, for example, 1 mm or less.

[0037] The second wavelength converter 5 has a light incident portion 51 and a light emitting portion 52. In the second wavelength converter 5, the light incident portion 51 is configured by a first end surface 531 of the core 53, and the light emitting portion 52 is configured by a second end surface 532 of the core 53.

[0038] In the second wavelength converter 5, the second excitation light P2 from the second solid-state light source 4 is incident on the light incident portion 51. From the light emitting portion 52 of the second wavelength converter 5, stimulated emission light including ASE is emitted as seed light P21 to P24. From the second wavelength converter 5, the second excitation light P2 is also emitted.

[0039] The second wavelength conversion element is Pr 3+ In this case, the second spontaneous emission light of multiple wavelengths generated in the second wavelength conversion section 5 may include, for example, spontaneous emission light of a wavelength of 482 nm (blue light), spontaneous emission light of a wavelength of 532 nm (green light), spontaneous emission light of a wavelength of 605 nm (orange light), spontaneous emission light of a wavelength of 637 nm (red light), spontaneous emission light of a wavelength of 698 nm, and spontaneous emission light of a wavelength of 719 nm (near-infrared light).

[0040] The second wavelength converter 5 emits multiple types of seed light P21 to P24 (see FIG. 1). The multiple types of seed light P21 to P24 emitted from the second wavelength converter 5 are incident on the first wavelength converter 3. More specifically, the multiple types of seed light P21 to P24 emitted from the second wavelength converter 5 are incident on the light incident section 31 of the first wavelength converter 3 via the optical member 6 and the optical element 12.

[0041] (2.5) Optical components 1, the optical member 6 is disposed between the second wavelength-converting section 5 and the first wavelength-converting section 3. More specifically, the optical member 6 is disposed between the second wavelength-converting section 5 and the optical element 12. As described above, the optical element 12 is a dichroic mirror, which transmits light from the optical member 6 side to the first wavelength-converting section 3 side and reflects light from the first solid-state light source 2 side toward the first wavelength-converting section 3.

[0042] As shown in FIGS. 4A to 4C, the optical member 6 has a rotating plate 68 and a plurality of (for example, four) filter sections 60 that correspond to light in a plurality of wavelength ranges.

[0043] The rotating plate 68 can rotate around the central axis of rotation A6 of the optical member 6. The central axis of rotation A6 is parallel to the direction in which the light emitting portion 52 of the second wavelength converter 5 and the optical element 12 are aligned (prescribed direction) (see FIG. 1). The light emitting portion 52 of the second wavelength converter 5, the optical element 12, and the light incident portion 31 of the first wavelength converter 3 are aligned on a straight line in the prescribed direction. The central axis of rotation A6 is not limited to being strictly parallel to the prescribed direction, and may be any angle with the prescribed direction of 5 degrees or less, for example.

[0044] When viewed from the thickness direction of the rotating plate 68, the outer edge of the rotating plate 68 is circular. The rotating plate 68 has a first main surface 681 located on the second wavelength conversion section 5 side in the thickness direction of the rotating plate 68 and a second main surface 682 opposite to the first main surface 681. The rotating plate 68 is connected to, for example, a rotating shaft 71 of the motor 7 and rotates together with the rotating shaft 71 of the motor 7. In the optical member 6, a part of the rotating shaft 71 of the motor 7 is disposed in a through hole 683 at the center of the rotating plate 68. The rotating plate 68 is disposed so that its thickness direction is along the rotation central axis A6. The optical member 6 is disposed so that the incident position of the light emitted from the second wavelength conversion section 5 is located away from the rotation central axis A6 in a direction perpendicular to the rotation central axis A6 of the optical member 6. The distance between the rotation axis A6 and the incident position is longer than the shortest distance between the rotation axis A6 and the filter section 60, and shorter than the longest distance between the rotation axis A6 and the outer edge of the filter section 60. The rotating plate 68 is translucent and transmits visible light. Therefore, the rotating plate 68 transmits the multiple types of seed light P21 to P24 emitted from the second wavelength conversion section 5. The rotating plate 68 is a glass substrate, but is not limited to this and may be, for example, a ceramic substrate or a resin substrate.

[0045] The filter sections 60 include transmission sections 61-64 that transmit light of a plurality of wavelength ranges. More specifically, the filter sections 60 correspond one-to-one to the transmission sections 61-64, and include a corresponding transmission section and a portion of the rotating plate 68 that overlaps with the corresponding transmission section. In the optical member 6, the filter sections 60 are arranged on a circumference centered on the rotation axis A6 of the optical member 6. When viewed from a direction along the rotation axis A6 of the optical member 6, the outer edge of the optical member 6 is circular, and each of the filter sections 60 is fan-shaped centered on the rotation axis A6. If the number of filter sections 60 is N1, the central angle of each of the filter sections 60 is 360° / N1 when viewed from a direction along the rotation axis A6 of the optical member 6. Therefore, when N1=4, the central angle of each of the filter sections 60 is 90° when viewed from a direction along the rotation axis A6 of the optical member 6. Each of the multiple wavelength ranges includes at least one wavelength of the second spontaneously emitted light among the multiple wavelengths of the second spontaneously emitted light generated in the second wavelength converter 5. The wavelengths of the second spontaneously emitted light included in each of the multiple wavelength ranges are different from each other.

[0046] The plurality of transmitting portions 61-64 are disposed on a first main surface 681 of the rotating plate 68. Each of the plurality of transmitting portions 61-64 is a multilayer film filter (dielectric multilayer film filter). In the optical member 6, the plurality of transmitting portions 61-64 are arranged on a circumference centered on the rotational axis A6 of the optical member 6. The plurality of transmitting portions 61-64 are arranged in the order of the transmitting portion 61, the transmitting portion 62, the transmitting portion 63, and the transmitting portion 64 in the rotational direction of the optical member 6, that is, in the direction along the rotational direction R1 (see FIG. 4A) of the rotational shaft 71 of the motor 7. The plurality of transmitting portions 61-64 are fan-shaped with the rotational axis A6 as the center, as viewed from the direction along the rotational axis A6. If the number of the plurality of transmitting portions 61-64 is M1 (=N1), the central angle of each of the plurality of transmitting portions 61-64 is 360° / M1, as viewed from the direction along the rotational axis A6 of the optical member 6. Therefore, when M1=4, the central angle of each of the multiple transmission parts 61 to 64 is 90° when viewed from a direction along the rotational center axis A6 of the optical member 6.

[0047] For ease of explanation, in the following, regarding the multiple types of seed light P21 to P24 emitted from the second wavelength conversion unit 5, the seed light P21 may be referred to as the first seed light P21, the seed light P22 as the second seed light P22, the seed light P23 as the third seed light P23, and the seed light P24 as the fourth seed light P24. The wavelengths of the first seed light P21, the second seed light P22, the third seed light P23, and the fourth seed light P24 are the same as the wavelengths of the second spontaneous emission light of different wavelengths among the multiple wavelengths of the second spontaneous emission light generated in the second wavelength conversion unit 5. The wavelengths of the first seed light P21, the second seed light P22, the third seed light P23, and the fourth seed light P24 are different from each other. When the second wavelength conversion element is Pr 3+ In this case, the wavelengths of the first seed light P21, the second seed light P22, the third seed light P23, and the fourth seed light P24 are, for example, 482 nm, 523 nm, 605 nm, and 637 nm, respectively. For convenience of explanation, the transmitting portion 61 may be referred to as the first transmitting portion 61, the transmitting portion 62 may be referred to as the second transmitting portion 62, the transmitting portion 63 may be referred to as the third transmitting portion 63, and the transmitting portion 64 may be referred to as the fourth transmitting portion 64. Among the multiple wavelength ranges, the wavelength range corresponding to the first transmitting portion 61 may be referred to as the first wavelength range, the wavelength range corresponding to the second transmitting portion 62 may be referred to as the second wavelength range, the wavelength range corresponding to the third transmitting portion 63 may be referred to as the third wavelength range, and the wavelength range corresponding to the fourth transmitting portion 64 may be referred to as the fourth wavelength range.

[0048] The first transmitting section 61 selectively transmits light in a first wavelength range. The first wavelength range includes the wavelength of the first seed light P21 and does not include the wavelengths of the second seed light P22, the third seed light P23, and the fourth seed light P24. The first wavelength range is, for example, 440 nm or more and 490 nm. The second transmitting section 62 selectively transmits light in a second wavelength range. The second wavelength range includes the wavelength of the second seed light P22 and does not include the wavelengths of the first seed light P21, the third seed light P23, and the fourth seed light P24. The second wavelength range is, for example, 510 nm or more and 550 nm or less. The third transmitting section 63 selectively transmits light in a third wavelength range. The third wavelength range includes the wavelength of the third seed light P23 and does not include the wavelengths of the first seed light P21, the second seed light P22, and the fourth seed light P24. The third wavelength range is, for example, 570 nm or more and 610 nm or less. The fourth transmitting portion 64 selectively transmits light in the fourth wavelength range. The fourth wavelength range includes the wavelength of the fourth seed light P24, and does not include the wavelengths of the first seed light P21, the second seed light P22, and the third seed light P23. The fourth wavelength range is, for example, 620 nm or more and 650 nm or less. In the optical member 6, the transmitting portions 61 to 64 are designed so that the first wavelength range, the second wavelength range, the third wavelength range, and the fourth wavelength range do not overlap with each other, but are not limited thereto. For example, the first wavelength range and the second wavelength range may partially overlap with each other, the second wavelength range and the third wavelength range may partially overlap with each other, or the third wavelength range and the fourth wavelength range may partially overlap with each other.

[0049] The optical member 6, while rotating in a rotation direction R1, receives a plurality of types of seed beams P21 to P24 and emits a first seed beam P21, a second seed beam P22, a third seed beam P23 and a fourth seed beam P24 in a time-division manner.

[0050] (2.6) Motor The motor 7 (see Figs. 1, 4A to 4C) rotates the optical member 6. More specifically, the motor 7 rotates the optical member 6 around the central axis A6 of rotation of the optical member 6. The motor 7 is, for example, a DC motor. The motor 7 is driven by the motor driving circuit 11 described above.

[0051] The motor 7 includes a motor body 70 and a rotating shaft 71 partially protruding from the motor body 70. In the motor 7, the rotating shaft 71 is connected to the optical member 6. The rotation speed of the rotating shaft 71 of the motor 7 is controlled by the control unit 8. More specifically, the rotation speed of the rotating shaft 71 of the motor 7 is determined by the motor drive circuit 11 being controlled by the control unit 8 to drive the motor 7.

[0052] (2.7) First drive circuit The first driving circuit 9 (see FIG. 1) drives the first solid-state light source 2. The first driving circuit 9 includes, for example, a series circuit of a first resistor and a first switching element connected between the first power supply circuit and the first solid-state light source 2. The first driving circuit 9 lights up the first solid-state light source 2 by supplying a driving current to the first solid-state light source 2. The first driving circuit 9 lights up the first solid-state light source 2 by turning on the first switching element by the control unit 8, and turns off the first solid-state light source 2 by turning off the first switching element by the control unit 8. The first switching element is, for example, a MOSFET, but is not limited thereto, and may be, for example, a FET other than a MOSFET or a bipolar transistor. The first power supply circuit is not included in the components of the light source system 1, but is not limited thereto and may be included.

[0053] (2.8) Second drive circuit The second driving circuit 10 (see FIG. 1) drives the second solid-state light source 4. The second driving circuit 10 includes, for example, a series circuit of a second resistor and a second switching element connected between the second power supply circuit and the second solid-state light source 4. The second driving circuit 10 supplies a driving current to the second solid-state light source 4 to turn on the second solid-state light source 4. The second driving circuit 10 turns on the second solid-state light source 4 when the control unit 8 turns on the second switching element, and turns off the second solid-state light source 4 when the control unit 8 turns off the second switching element. In the light source system 1, the second switching element is PWM-controlled by the control unit 8. As a result, the control unit 8 PWM-controls the second solid-state light source 4. The second switching element is, for example, a MOSFET, but is not limited thereto, and may be, for example, a FET other than a MOSFET or a bipolar transistor. The second power supply circuit is not included in the components of the light source system 1, but is not limited thereto and may be included.

[0054] (2.9) Motor drive circuit The motor drive circuit 11 (see FIG. 1) drives the motor 7. More specifically, the motor drive circuit 11 is controlled by the control unit 8 to rotate the rotary shaft 71 of the motor 7.

[0055] A power supply voltage is supplied from, for example, a third power supply circuit to the motor drive circuit 11. The third power supply circuit is not included in the components of the light source system 1, but is not limited to this and may be included.

[0056] (2.10) Control section The control unit 8 (see FIG. 1 ) controls the first solid-state light source 2, the second solid-state light source 4, and the motor 7. The control unit 8 controls the first solid-state light source 2 by controlling the first drive circuit 9. More specifically, the control unit 8 controls the output of the first solid-state light source 2 by controlling the first drive circuit 9. The control unit 8 controls the second solid-state light source 4 by controlling the second drive circuit 10. More specifically, the control unit 8 controls the output of the second solid-state light source 4 by controlling the second drive circuit 10. The control unit 8 controls the motor 7 by controlling the motor drive circuit 11. More specifically, the control unit 8 controls the rotation speed and the like of the motor 7 by controlling the motor drive circuit 11.

[0057] The control unit 8 PWM-controls the second solid-state light source 4 so as to drive the second solid-state light source 4 to pulse-blink at a constant period T0, for example, as shown in Fig. 5. More specifically, the control unit 8 PWM-controls the second switching element of the second drive circuit 10 at a constant period T0, thereby PWM-controlling the second solid-state light source 4. The control unit 8 controls the rotation of the optical member 6 so that the light from the second wavelength conversion unit 5 can be incident on the first transmission unit 61 during a first period T1 having the same time as the constant period T0, the light from the second wavelength conversion unit 5 can be incident on the second transmission unit 62 during a second period T2 having the same time as the constant period T0, the light from the second wavelength conversion unit 5 can be incident on the third transmission unit 63 during a third period T3 having the same time as the constant period T0, and the light from the second wavelength conversion unit 5 can be incident on the fourth transmission unit 64 during a fourth period T4 having the same time as the constant period T0. Moreover, the control unit 8 controls the second solid-state light source 4 by PWM control, thereby controlling the lighting periods (ON periods in FIG. 5) of the second solid-state light source 4 in the first period T1, the second period T2, the third period T3, and the fourth period T4. The control unit 8 controls the lighting periods of the second solid-state light source 4 by cyclically repeating the first period T1, the second period T2, the third period T3, and the fourth period T4. This allows the control unit 8 to adjust the intensity of each of the seed beams P21 to P24 incident on the first wavelength conversion unit 3. Therefore, in the light source system 1, the control unit 8 controls the second solid-state light source 4 and the optical member 6, thereby making it possible to adjust the light intensity and color of the light emitted from the light source system 1 (light emitted from the first wavelength conversion unit 3). The control unit 8 controls the lighting periods (ON periods in FIG. 5) of the second solid-state light source 4 in each of the first period T1, the second period T2, the third period T3, and the fourth period T4 based on, for example, dimming / toning instruction information input from an input unit that accepts operation input from a user of the light source system 1 or an external controller. From the viewpoint of suppressing flicker, the frequency (1 / T0) when the control unit 8 PWM controls the second solid-state light source 4 is preferably a frequency calculated by 200 Hz×M1. Therefore, when M1=4, the frequency when the control unit 8 PWM controls the second solid-state light source 4 is preferably 800 Hz or more.

[0058] The control unit 8 controls the rotation of the optical member 6 so that the timing at which the rotating optical member 6 returns to the rotation reference position is synchronized with the start timing of the first period T1 of the PWM signal that controls the second solid-state light source 4. The rotation reference position means a position that is a predetermined reference for the rotation position of the optical member 6, and is, for example, a position where the boundary between the fourth transmitting portion 64 and the first transmitting portion 61 is the incident position of light from the second wavelength converting portion 5. The control unit 8 controls the motor 7 so that the time it takes for the optical member 6 to make one rotation is the same as the total time of the first period T1, the second period T2, the third period T3, and the fourth period T4.

[0059] The control unit 8 controls the motor drive circuit 11 so that the timing at which the optical member 6 returns to the rotation reference position is synchronized with the start timing of the first period T1, based on a detection signal from a detection unit that detects the rotation angle of the optical member 6 from the rotation reference position. The rotation angle of the optical member 6 from the rotation reference position corresponds to the phase difference between the rotation position of the optical member 6 and the rotation reference position. The detection unit is composed of, for example, a photointerrupter or a Hall element, and outputs a detection signal when the optical member 6 returns to the rotation reference position.

[0060] The control unit 8 includes, for example, a computer system. The computer system is mainly composed of a processor and a memory as hardware. The function of the control unit 8 is realized by the processor executing a program recorded in the memory of the computer system. The program may be pre-recorded in the memory of the computer system, may be provided through an electric communication line, or may be provided by being recorded in a non-transitory recording medium such as a memory card, an optical disk, or a hard disk drive that can be read by the computer system. The processor of the computer system is composed of one or more electronic circuits including a semiconductor integrated circuit (IC) or a large scale integrated circuit (LSI). The integrated circuits such as IC or LSI mentioned here are called by different names depending on the degree of integration, and include integrated circuits called system LSI, VLSI (Very Large Scale Integration), or ULSI (Ultra Large Scale Integration). Furthermore, a field-programmable gate array (FPGA) that is programmed after the manufacture of the LSI, or a logic device that can reconfigure the connection relationship inside the LSI or reconfigure the circuit partition inside the LSI, can also be adopted as a processor. The electronic circuits may be integrated in one chip or distributed across multiple chips. The multiple chips may be integrated into one device, or may be distributed across multiple devices. The computer system referred to here includes a microcontroller having one or more processors and one or more memories. Therefore, the microcontroller is also composed of one or more electronic circuits including a semiconductor integrated circuit or a large-scale integrated circuit.

[0061] (3) Operation of the light source system In the light source system 1, the first solid-state light source 2 emits the first excitation light P1, and the second solid-state light source 4 emits the second excitation light P2. In this way, in the light source system 1, the first excitation light P1 is incident on the first wavelength conversion unit 3, and the second excitation light P2 is incident on the second wavelength conversion unit 5. Here, the control unit 8 PWM controls the second solid-state light source 4. In addition, in the light source system 1, the control unit 8 rotates the optical member 6. In this way, in the light source system 1, the first period T1, the second period T2, the third period T3, and the fourth period T4 are cyclically repeated to control the lighting period of the second solid-state light source 4. In this way, the control unit 8 can adjust the intensity of each of the seed light beams P21 to P24 incident on the first wavelength conversion unit 3. Therefore, in the light source system 1, the control unit 8 controls the second solid-state light source 4 and the optical member 6, thereby making it possible to adjust the light and color of the light emitted from the light source system 1 (light emitted from the first wavelength conversion unit 3). In the light source system 1, the light emitted from the first wavelength converter 3 may include stimulated emission light P11 having the same wavelength as the first seed light P21, stimulated emission light P12 having the same wavelength as the second seed light P22, stimulated emission light P13 having the same wavelength as the third seed light P23, and stimulated emission light P14 having the same wavelength as the fourth seed light P24. The light emitted from the first wavelength converter 3 may also include light having the same wavelength as the first excitation light P1 (a part of the first excitation light P1) and light having the same wavelength as the second excitation light P2 (a part of the second excitation light P2). The intensities of the stimulated emission light P11, P12, P13, and P14 are greater than the intensities of the seed lights P21, P22, P23, and P24, respectively.

[0062] (4) Summary The light source system 1 according to the first embodiment includes a first solid-state light source 2, a first wavelength conversion unit 3, a second solid-state light source 4, a second wavelength conversion unit 5, an optical member 6, a motor 7, and a control unit 8. The first solid-state light source 2 emits a first excitation light P1. The first wavelength conversion unit 3 is an optical fiber including a first wavelength conversion element that is excited by the first excitation light P1 and capable of generating first spontaneous emission light of a plurality of wavelengths longer than the first excitation light P1 and is excitable by the first amplified spontaneous emission light. The second solid-state light source 4 emits a second excitation light P2. The second wavelength conversion unit 5 includes a second wavelength conversion element that is excited by the second excitation light P2 and capable of generating second spontaneous emission light of a plurality of wavelengths longer than the second excitation light P2 and is excitable by the second amplified spontaneous emission light. The optical member 6 is disposed between the second wavelength conversion unit 5 and the first wavelength conversion unit 3. The optical member 6 has a plurality of filter units 60 corresponding to light of a plurality of wavelength ranges. The plurality of filter sections 60 transmit light of corresponding wavelength ranges among the light of the plurality of wavelength ranges. The motor 7 rotates the optical member 6. The control section 8 controls the motor 7 and the second solid-state light source 4. In the optical member 6, the plurality of filter sections 60 are arranged on a circumference centered on the central axis A6 of rotation of the optical member 6. Each of the plurality of wavelength ranges includes the wavelength of at least one of the second spontaneously emitted light of the plurality of wavelengths generated in the second wavelength conversion section 5.

[0063] In the light source system 1 according to the first embodiment, it is possible to adjust the light intensity and the color tone without using a solid-state light source that emits seed light.

[0064] In the light source system 1 according to the first embodiment, the first wavelength conversion unit 3 is a first wavelength conversion element. 3+ The second wavelength-converting portion 5 contains Pr as a second wavelength-converting element. 3+ can increase the intensities of the green and red stimulated emission lights emitted from the first wavelength-converter 3. This enables the light source system 1 according to the first embodiment to improve the color rendering of the light emitted from the first wavelength-converter 3.

[0065] (Embodiment 2) Hereinafter, a light source system 1a according to the second embodiment will be described with reference to Figures 6, 7A, 7B, and 7C. Regarding the light source system 1a according to the second embodiment, components similar to those of the light source system 1 according to the first embodiment will be denoted by the same reference numerals and will not be described.

[0066] The light source system 1a according to the second embodiment differs from the light source system 1 according to the first embodiment in that the light source system 1a includes an optical member 6a instead of the optical member 6 in the light source system 1 according to the first embodiment.

[0067] The light source system 1a does not include the optical element 12 in the light source system 1, and the first solid-state light source 2, the optical member 6a, and the first wavelength converter 3 are arranged in a straight line. The optical member 6a is disposed between the first solid-state light source 2 and the first wavelength converter 3.

[0068] Moreover, the optical member 6a is disposed between the second wavelength-converter 5 and the first wavelength-converter 3. Here, the direction in which the light exit portion 52 of the second wavelength-converter 5 and the optical member 6a are arranged is perpendicular to the direction in which the light entrance portion 31 of the first wavelength-converter 3 and the optical member 6a are arranged.

[0069] As shown in FIGS. 7A to 7C, the optical member 6a has a rotating plate 68a and a plurality of (for example, four) filter portions 60a that correspond to light in a plurality of wavelength ranges.

[0070] The rotating plate 68a can rotate around a rotation axis A6a of the optical member 6a. The rotation axis A6a intersects with the direction in which the first solid-state light source 2 and the light entrance portion 31 of the first wavelength converter 3 are arranged. The smaller of the two intersection angles at this time is 45°. This intersection angle is not limited to being strictly 45°, and may be within a range of 42° to 48°, for example.

[0071] When viewed from the thickness direction of the rotating plate 68a, the outer edge of the rotating plate 68a is circular. The rotating plate 68a has a first main surface 681a located on the second wavelength conversion section 5 side in the thickness direction of the rotating plate 68a and a second main surface 682a opposite to the first main surface 681a. The rotating plate 68a is connected to, for example, a rotating shaft 71 of the motor 7 and rotates together with the rotating shaft 71 of the motor 7. In the optical member 6a, a part of the rotating shaft 71 of the motor 7 is disposed in a through hole 683a at the center of the rotating plate 68a. The rotating plate 68a is disposed so that its thickness direction is along the rotation central axis A6a. The optical member 6a is disposed so that the incident position of the light emitted from the second wavelength conversion section 5 is located away from the rotation central axis A6a in a direction perpendicular to the rotation central axis A6a of the optical member 6a. The distance between the rotation axis A6a and the incident position is longer than the shortest distance between the rotation axis A6a and the filter unit 60a, and shorter than the longest distance between the rotation axis A6a and the outer edge of the filter unit 60a. The rotating plate 68a is translucent and transmits visible light. Therefore, the rotating plate 68a transmits the first excitation light P1 emitted from the first solid-state light source 2. The rotating plate 68a is a glass substrate, but is not limited thereto, and may be, for example, a ceramic substrate or a resin substrate.

[0072] The optical member 6a reflects the multiple types of seed light P21 to P24 emitted from the second wavelength converter 5.

[0073] The filter sections 60a include reflecting sections 61a to 64a that reflect light in a plurality of wavelength ranges. More specifically, the filter sections 60a correspond one-to-one to the reflecting sections 61a to 64a. In the optical member 6a, the filter sections 60a are arranged on a circumference centered on the rotational axis A6a of the optical member 6a. When viewed from a direction along the rotational axis A6a of the optical member 6a, the outer edge of the optical member 6a is circular, and each of the filter sections 60a is fan-shaped centered on the rotational axis A6a. If the number of filter sections 60a is N2, when viewed from a direction along the rotational axis A6a of the optical member 6a, the central angle of each of the filter sections 60a is 360° / N2. Therefore, when N2=4, when viewed from a direction along the rotational axis A6a of the optical member 6a, the central angle of each of the filter sections 60a is 90°. Each of the plurality of wavelength ranges includes at least one wavelength of second spontaneous emission light among the plurality of wavelengths of second spontaneous emission light generated in the second wavelength converter 5.

[0074] The plurality of reflecting portions 61a to 64a are disposed on a first main surface 681a of the rotating plate 68a. Each of the plurality of reflecting portions 61a to 64a is a multilayer mirror. In the optical member 6a, the plurality of reflecting portions 61a to 64a are arranged on a circumference centered on the rotation central axis A6a of the optical member 6a. The plurality of reflecting portions 61a to 64a are arranged in the order of the reflecting portion 61a, the reflecting portion 62a, the reflecting portion 63a, and the reflecting portion 64a in the direction along the rotational direction of the optical member 6a, that is, the direction along the rotational direction R1 (see FIG. 7A) of the rotating shaft 71 of the motor 7. The plurality of reflecting portions 61a to 64a are fan-shaped with the rotational central axis A6a as the center when viewed from the direction along the rotational central axis A6a. If the number of the reflecting portions 61a-64a is M2 (=N2), the central angle of each of the reflecting portions 61a-64a is 360° / M2 when viewed from the direction along the rotational axis A6a of the optical member 6a. Therefore, when M2=4, the central angle of each of the reflecting portions 61a-64a is 90° when viewed from the direction along the rotational axis A6a of the optical member 6a.

[0075] For ease of explanation, hereinafter, the reflecting portion 61a may be referred to as the first reflecting portion 61a, the reflecting portion 62a as the second reflecting portion 62a, the reflecting portion 63a as the third reflecting portion 63a, and the reflecting portion 64a as the fourth reflecting portion 64a. In addition, among the multiple wavelength ranges, the wavelength range corresponding to the first reflecting portion 61a may be referred to as the first wavelength range, the wavelength range corresponding to the second reflecting portion 62a as the second wavelength range, the wavelength range corresponding to the third reflecting portion 63a as the third wavelength range, and the wavelength range corresponding to the fourth reflecting portion 64a as the fourth wavelength range.

[0076] The first reflecting portion 61a selectively reflects light in a first wavelength range. The first wavelength range includes the wavelength of the first seed light P21, and does not include the wavelengths of the second seed light P22, the third seed light P23, and the fourth seed light P24. The second reflecting portion 62a selectively reflects light in a second wavelength range. The second wavelength range includes the wavelength of the second seed light P22, and does not include the wavelengths of the first seed light P21, the third seed light P23, and the fourth seed light P24. The third reflecting portion 63a selectively reflects light in a third wavelength range. The third wavelength range includes the wavelength of the third seed light P23, and does not include the wavelengths of the first seed light P21, the second seed light P22, and the fourth seed light P24. The fourth reflecting portion 64a selectively reflects light in a fourth wavelength range. The fourth wavelength range includes the wavelength of the fourth seed light P24, and does not include the wavelength of the first seed light P21, the wavelength of the second seed light P22, and the wavelength of the third seed light P23. In the optical member 6a, the reflecting portions 61a to 64a are designed so that the first wavelength range, the second wavelength range, the third wavelength range, and the fourth wavelength range do not overlap with each other, but this is not limited thereto, and for example, the first wavelength range and the second wavelength range may partially overlap with each other, the second wavelength range and the third wavelength range may partially overlap with each other, or the third wavelength range and the fourth wavelength range may partially overlap with each other.

[0077] While rotating in the rotation direction R1, the optical member 6a receives a plurality of types of seed light P21 to P24 and emits a first seed light P21, a second seed light P22, a third seed light P23, and a fourth seed light P24 in a time-division manner. The first reflecting portion 61a transmits light having the wavelength of the first excitation light P1. Therefore, the first excitation light P1 incident on the second main surface 682a of the rotating plate 68a in the optical member 6a is incident on the first wavelength converter 3 during the same first period T1 (see FIG. 5) as the first seed light P21. The second reflecting portion 62a, the third reflecting portion 63a, and the fourth reflecting portion 64a transmit light having the wavelength of the first excitation light P1.

[0078] The light source system 1a according to the second embodiment includes a first solid-state light source 2, a first wavelength conversion unit 3, a second solid-state light source 4, a second wavelength conversion unit 5, an optical member 6a, a motor 7, and a control unit 8. The first solid-state light source 2 emits a first excitation light P1. The first wavelength conversion unit 3 is an optical fiber including a first wavelength conversion element that is excited by the first excitation light P1 and capable of generating first spontaneous emission light of a plurality of wavelengths longer than the first excitation light P1 and is excitable by the first amplified spontaneous emission light. The second solid-state light source 4 emits a second excitation light P2. The second wavelength conversion unit 5 includes a second wavelength conversion element that is excited by the second excitation light P2 and capable of generating second spontaneous emission light of a plurality of wavelengths longer than the second excitation light P2 and is excitable by the second amplified spontaneous emission light. The optical member 6a is disposed between the second wavelength conversion unit 5 and the first wavelength conversion unit 3. The optical member 6 has a plurality of filter sections 60a corresponding to light in a plurality of wavelength ranges. The plurality of filter sections 60a reflect light in a corresponding wavelength range among the light in the plurality of wavelength ranges. The motor 7 rotates the optical member 6a. The control unit 8 controls the motor 7 and the second solid-state light source 4. In the optical member 6a, the plurality of filter sections 60a are arranged on a circumference centered on the rotation central axis A6a of the optical member 6a. Each of the plurality of wavelength ranges includes at least one wavelength of the second spontaneous emission light among the plurality of wavelengths of the second spontaneous emission light generated in the second wavelength conversion unit 5.

[0079] In the light source system 1a according to the second embodiment, it is possible to adjust the light intensity and the color tone without using a solid-state light source that emits seed light.

[0080] (Modification) The above-mentioned first and second embodiments are merely one of various embodiments of the present disclosure. The above-mentioned first and second embodiments can be modified in various ways depending on the design and the like as long as the object of the present disclosure can be achieved.

[0081] For example, in the light source systems 1 and 1a, the control unit 8 is not limited to a configuration in which it controls the first solid-state light source 2, the second solid-state light source 4, and the motor 7, but may be configured to control the second solid-state light source 4 and the motor 7. In this case, the light source systems 1 and 1a may include, for example, a second control unit that controls the first solid-state light source 2, in addition to the first control unit 8 which is the control unit 8.

[0082] The laser light source included in the first solid-state light source 2 is not limited to a semiconductor laser that emits blue laser light, and may be, for example, a semiconductor laser that emits purple laser light. The first solid-state light source 2 is not limited to a semiconductor laser, and may be, for example, a configuration including an LED (Light Emitting Diode) light source and an optical system.

[0083] The laser light source included in the second solid-state light source 4 is not limited to a semiconductor laser that emits blue laser light, but may be, for example, a semiconductor laser that emits purple laser light. The second solid-state light source 4 is not limited to a semiconductor laser, but may be, for example, a configuration including an LED light source and an optical system.

[0084] Furthermore, the wavelength of the second excitation light P2 is not limited to being the same as the wavelength of the first excitation light P1, and may be a different wavelength.

[0085] Furthermore, the second wavelength-converting part 5 is not limited to an optical fiber, but may be an optical rod. The optical rod has a core and cladding similar to those of an optical fiber. The diameter of the optical rod is larger than the diameter of the core of an optical fiber. The optical rod is inflexible. While an optical fiber is in the form of a flexible fiber, the optical rod is in the form of an inflexible rod.

[0086] In the light source system 1, 1a, the first wavelength conversion unit 3 may include a plurality of types of first wavelength conversion elements as the first wavelength conversion elements, and the second wavelength conversion element may include a plurality of types of second wavelength conversion elements as the second wavelength conversion elements. In this case, the light source system 1, 1a can excite the first wavelength conversion element with the second amplified spontaneous emission light from the second wavelength conversion element, and generate, from the first wavelength conversion element, a first amplified spontaneous emission light having a wavelength different from the second amplified spontaneous emission light from the second wavelength conversion element. More specifically, for example, the first wavelength conversion unit 3 may include, for example, Pr 3+ and Tb 3+ In the case where the second wavelength conversion unit 5 includes, for example, Pr 3+ and Tb 3+ The second wavelength converting portion 5 may include, for example, Pr 3+ and Dy 3+ and

[0087] Furthermore, in the light source system 1, when the first excitation light P1 is blue light as described above, the optical member 6 may be configured not to have the first transmitting portion 61 that transmits light in the first wavelength range. In this case, the central angle of each of the second transmitting portion 62, the third transmitting portion 63, and the fourth transmitting portion 64, which are sector-shaped when viewed from the direction along the rotation central axis A6, may be 120°. In this case, the optical member 6 is optically designed such that the second transmitting portion 62, the third transmitting portion 63, and the fourth transmitting portion 64 do not transmit the second excitation light P2, for example.

[0088] Furthermore, in the direction along the rotation direction R1 (see Figure 4A) of the rotating shaft 71 of the motor 7, the order in which the first transparent section 61, the second transparent section 62, the third transparent section 63, and the fourth transparent section 64 are arranged is not limited to the example described above, and may be, for example, the order of the first transparent section 61, the third transparent section 63, the second transparent section 62, and the fourth transparent section 64.

[0089] Furthermore, in the light source system 1, when the second excitation light P2 is blue light as described above, the optical element 6 may have a central angle of 72° for each of the four filter sections 60, and a central angle of the sector-shaped area on the rotating plate 68 that transmits the second excitation light P2 may be 72°.

[0090] In addition, in one modified example of the light source system 1, the first solid-state light source 2, the optical element 12, and the light entrance section 31 of the first wavelength converter 3 are aligned in a straight line, and the optical element 12 may be configured to transmit the first excitation light P1 and reflect the seed light P21 to P24.

[0091] In addition, the optical element 6 may be configured so that the radius of the rotating plate 68 is circular and shorter than the distance between the rotation center axis A6 and the incident position, and the first transmitting portion 61, the second transmitting portion 62, the third transmitting portion 63 and the fourth transmitting portion 64 are arranged on the side edges of the rotating plate 68.

[0092] Furthermore, the optical element 12 is not limited to a dichroic mirror, but may be, for example, a prism.

[0093] Furthermore, in the direction along the rotation direction R1 (see FIG. 7A) of the rotating shaft 71 of the motor 7, the order in which the first reflecting portion 61a, the second reflecting portion 62a, the third reflecting portion 63a and the fourth reflecting portion 64a are arranged is not limited to the above example, and may be, for example, the order of the first reflecting portion 61a, the third reflecting portion 63a, the second reflecting portion 62a and the fourth reflecting portion 64a.

[0094] The control unit 8 is not limited to the example of controlling the second solid-state light source 4 with PWM control, and may control the second solid-state light source 4 with another control method.

[0095] (Aspect) Based on the above-described first and second embodiments, the present specification discloses the following aspects.

[0096] A light source system (1; 1a) according to a first aspect includes a first solid-state light source (2), a first wavelength conversion unit (3), a second solid-state light source (4), a second wavelength conversion unit (5), an optical member (6; 6a), a motor (7), and a control unit (8). The first solid-state light source (2) emits a first excitation light (P1). The first wavelength conversion unit (3) is an optical fiber including a first wavelength conversion element that is excited by the first excitation light (P1) to generate first spontaneous emission light of a plurality of wavelengths longer than the first excitation light (P1) and is excitable by the first amplified spontaneous emission light. The second solid-state light source (4) emits a second excitation light (P2). The second wavelength conversion unit (5) includes a second wavelength conversion element that is excited by the second excitation light (P2) to generate second spontaneous emission light of a plurality of wavelengths longer than the second excitation light (P2) and is excitable by the second amplified spontaneous emission light. The optical member (6; 6a) is disposed between the second wavelength conversion unit (5) and the first wavelength conversion unit (3). The optical member (6; 6a) has a plurality of filter units (60; 60a) corresponding to light of a plurality of wavelength ranges. The motor (7) rotates the optical member (6; 6a). The control unit (8) controls the motor (7) and the second solid-state light source (4). In the optical member (6), the plurality of filter units (60; 60a) are arranged on a circumference centered on the rotation central axis (A6; A6a) of the optical member (6; 6a). Each of the plurality of wavelength ranges includes at least one wavelength of second spontaneous emission light among the plurality of wavelengths of second spontaneous emission light generated in the second wavelength converter (5).

[0097] The light source system (1; 1a) according to the first embodiment is capable of adjusting the light intensity and color tone without using a solid-state light source that emits seed light.

[0098] In the light source system (1; 1a) according to the second aspect, in the first aspect, the second wavelength converter (5) is an optical fiber.

[0099] In the light source system (1; 1a) of the second aspect, for example, the core diameter of the optical fiber constituting the second wavelength conversion section (5) is the same as the core diameter of the optical fiber constituting the first wavelength conversion section (3), thereby making it easy to optically couple the light emitted from the second wavelength conversion section (5) to the first wavelength conversion section (3).

[0100] In the light source system (1; 1a) according to the third aspect, in the first or second aspect, the second wavelength converting element is the same type of element as the first wavelength converting element.

[0101] The light source system (1; 1a) according to the third aspect can utilize multiple types of second spontaneously emitted light generated in the second wavelength conversion element, and multiple light beams having the same wavelengths as the multiple types of second spontaneously emitted light, as seed light (P21 to P24) that is incident on the first wavelength conversion section (3).

[0102] In the light source system (1) according to the fourth aspect, in any one of the first to third aspects, the multiple filter sections (60) include multiple transmission sections (61-64) arranged on a circumference centered on the central axis of rotation (A6) and transmitting light of different wavelength ranges.

[0103] In a light source system (1a) according to a fifth aspect, in any one of the first to third aspects, the multiple filter sections (60a) include multiple reflecting sections (61a to 64a) arranged on a circumference centered on the central axis of rotation (A6a) and reflecting light of different wavelength ranges.

[0104] The light source system (1) according to the sixth aspect is the fourth aspect, and further includes an optical element (12). The optical element (12) is disposed between the optical member (6) and the first wavelength conversion section (3). The optical element (12) transmits light from the optical member (6) side to the first wavelength conversion section (3) side, and reflects the first excitation light (P1) emitted from the first solid-state light source (2) toward the first wavelength conversion section (3).

[0105] The light source system (1) of the sixth aspect makes it possible to align the light emission section (52) of the second wavelength conversion section (5), the optical member (6), and the light incidence section (31) of the first wavelength conversion section (3) in a straight line, making it easy to optically couple the light emitted from the second wavelength conversion section (5) to the first wavelength conversion section (3).

[0106] In a light source system (1; 1a) according to a seventh aspect, in any one of the fourth to sixth aspects, the multiple wavelength ranges include a wavelength range of 510 nm or more and 550 nm or less, and a wavelength range of 620 nm or more and 650 nm or less.

[0107] The light source system (1;1a) of the seventh aspect is capable of making the light emitted from the second wavelength converter (5) having a wavelength in the wavelength range of 510 nm or more and 550 nm or less and the light having a wavelength in the wavelength range of 620 nm or more and 650 nm or less incident on the first wavelength converter (3).

[0108] In a light source system (1; 1a) according to an eighth aspect, in any one of the first to seventh aspects, the second solid-state light source (4) includes a laser light source.

[0109] The light source system (1; 1a) according to the eighth aspect can increase the intensity of the second excitation light (P2).

[0110] In a light source system (1; 1a) according to a ninth aspect, in any one of the first to eighth aspects, the control unit (8) PWM controls the second solid-state light source (4).

[0111] The light source system (1; 1a) according to the ninth aspect is capable of adjusting the brightness and color of the light emitted from the first wavelength converter (3) by PWM controlling the second solid-state light source (4).

[0112] In the light source system (1; 1a) according to a tenth aspect, in any one of the fourth to seventh aspects, the control unit (8) PWM controls the second solid-state light source (4). The plurality of wavelength ranges are four wavelength ranges. The frequency when the control unit (8) PWM controls the second solid-state light source (4) is 800 Hz or more.

[0113] The light source system (1; 1a) according to the tenth aspect can suppress flicker.

[0114] In a light source system (1;1a) according to an eleventh aspect, in any one of the first to tenth aspects, each of the first wavelength conversion element and the second wavelength conversion element contains an element selected from the group consisting of Pr, Tb, Ho, Dy, Er, Eu, Nd and Mn. [Explanation of symbols]

[0115] 1. 1a Light source system 2 1st solid state light source 3. First Wavelength Conversion Section 31 Light incidence part 4 Second solid state light source 5 Second Wavelength Conversion Section 52 Light emitting part 6, 6a Optical components 60, 60a Filter section 61~64 Transparent part 61a~64a Reflector 7 Motor 8. Control Unit 12 Optical elements A6, A6a Rotation axis P1 First excitation light P2 Second excitation light

Claims

1. a first solid-state light source that emits a first excitation light; a first wavelength converting unit which is an optical fiber including a first wavelength converting element capable of being excited by the first excitation light to generate first spontaneous emission light having a plurality of wavelengths longer than the first excitation light and capable of being excited by a first amplified spontaneous emission light; a second solid-state light source that emits second excitation light; a second wavelength conversion unit including a second wavelength conversion element that is excited by the second excitation light to generate second spontaneous emission light having a plurality of wavelengths longer than the second excitation light and that is excitable by the second amplified spontaneous emission light; an optical member disposed between the second wavelength conversion unit and the first wavelength conversion unit and having a plurality of filter units corresponding to light of a plurality of wavelength ranges; A motor that rotates the optical member; a control unit that controls the motor and the second solid-state light source, In the optical member, the plurality of filter portions are arranged on a circumference centered on a rotation central axis of the optical member. Each of the plurality of wavelength ranges includes at least one wavelength of second spontaneous emission light among the plurality of wavelengths of second spontaneous emission light generated in the second wavelength conversion unit. Light source system.

2. The second wavelength converting portion is an optical fiber. The light source system of claim 1 .

3. The second wavelength converting element is an element of the same type as the first wavelength converting element.

3. A light source system according to claim 1 or 2.

4. The plurality of filter sections include a plurality of transmission sections arranged on a circumference centered on the central axis of rotation and transmitting light of different wavelength ranges from each other.

3. A light source system according to claim 1 or 2.

5. The plurality of filter sections include a plurality of reflecting sections arranged on a circumference centered on the central axis of rotation and reflecting light of different wavelength ranges from each other.

3. A light source system according to claim 1 or 2.

6. Further comprising an optical element disposed between the optical member and the first wavelength conversion unit, transmitting light from the optical member side to the first wavelength conversion unit side, and reflecting the first excitation light emitted from the first solid-state light source toward the first wavelength conversion unit.

5. The light source system of claim 4.

7. The plurality of wavelength ranges are A wavelength range of 510 nm or more and 550 nm or less; A wavelength range of 620 nm or more and 650 nm or less, 5. The light source system of claim 4.

8. The second solid-state light source includes a laser light source.

3. A light source system according to claim 1 or 2.

9. The control unit PWM controls the second solid-state light source.

3. A light source system according to claim 1 or 2.

10. The control unit PWM controls the second solid-state light source, The plurality of wavelength ranges are four wavelength ranges, The frequency when the control unit PWM controls the second solid-state light source is 800 Hz or more.

5. The light source system of claim 4.

11. Each of the first wavelength converting element and the second wavelength converting element includes an element selected from the group consisting of Pr, Tb, Ho, Dy, Er, Eu, Nd, and Mn; 3. A light source system according to claim 1 or 2.

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