Light emitting encapsulation and light source arrangement

Abstract

A light emitting seal includes a case that houses a discharge gas, a first opening and a second opening are formed in the case, first light is incident through the first opening along a first optical axis, second light is emitted through the second opening along a second optical axis, a first window portion that hermetically seals the first opening, a second window portion that hermetically seals the second opening, and a first electrode and a second electrode. The case is formed of a light shielding material that does not transmit the first light and the second light. An internal space is defined by the case, the first window portion, and the second window portion, and the internal space is filled with the discharge gas. The first opening and the second opening are arranged so that the first optical axis and the second optical axis intersect each other.

Description

Technical Field

[0001] This invention relates to a light-emitting sealing body and a light source device. Background Technology

[0002] A laser-excited light source is a source that maintains plasma generated in a discharge gas by laser irradiation and outputs light from the plasma as output light. Patent Document 1 describes a laser-excited light source comprising: a first container for containing the discharge gas and a second container for containing the first container. The second container is provided with a light-transmitting window for laser light to pass through (i.e., transmit), and a light-transmitting window for output light to pass through.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: US Patent No. 9,814,126 Summary of the Invention

[0006] The technical problem that the invention aims to solve

[0007] In the aforementioned laser-excited light source, light loss occurs as the laser and output light pass through the light-transmitting window and the first container. Therefore, there is room for improvement from the perspectives of increasing efficiency and output.

[0008] One objective of this invention is to provide a light-emitting sealing body and a light source device capable of achieving high efficiency and high output.

[0009] Technical solutions for solving technical problems

[0010] One aspect of the present invention includes a light-emitting sealing body comprising: a housing for containing discharge gas, wherein the housing has a first opening and a second opening, wherein a first light, which is a laser for maintaining plasma generated in the discharge gas, is incident along a first optical axis through the first opening, and a second light, which is light from the plasma, is emitted along a second optical axis through the second opening; a first window that hermetically seals the first opening and allows the first light to pass through; a second window that hermetically seals the second opening and allows the second light to pass through; and a first electrode and a second electrode that are opposite each other across the intersection of the first and second optical axes, wherein the housing is formed of a light-shielding material that prevents the first and second light from passing through, and an internal space is defined by the housing, the first window and the second window, the internal space being filled with discharge gas, and the first opening and the second opening being arranged such that the first and second optical axes intersect each other.

[0011] Within this luminescent sealing body, a first electrode and a second electrode are disposed facing each other, separated by the intersection of a first optical axis and a second optical axis. Therefore, by applying a voltage between the first and second electrodes, plasma can be generated between them. The housing is formed of a light-shielding material that prevents the first and second light rays from passing through. The housing, the first window, and the second window define an internal space filled with a discharge gas. Thus, since the first and second light rays do not pass through components other than the first and second windows, light loss can be reduced. As a result, high efficiency and high output can be achieved.

[0012] Alternatively, the first window portion may have a first window component that allows first light to pass through, and the second window portion may have a second window component that allows second light to pass through. In this case, window components corresponding to desired characteristics can be provided in both the first and second window portions.

[0013] The first window component and the second window component can be formed from the same material or from different materials. In this case, the optimal material can be selected according to the desired wavelength region.

[0014] The first window component and the second window component can each be formed into a flat plate. In this case, astigmatism can be suppressed.

[0015] The first and second window components can each be formed of a material including at least one of diamond, sapphire, quartz, Kovar glass, and magnesium fluoride. In this case, longer wavelength light, such as in the infrared region, can pass through the first and second window components.

[0016] Alternatively, the first window portion may also have a first frame component that is airtightly fixed to the housing, and the second window portion may also have a second frame component that is airtightly fixed to the housing. The first window component is airtightly joined to the first frame component using a first bonding material, and the second window component is airtightly joined to the second frame component using a second bonding material. In this case, the first window component can be well joined to the first frame component, and the second window component can be well joined to the second frame component.

[0017] The first bonding material and the second bonding material can each be a metallic solder, more preferably a silver solder doped with titanium. In this case, even in a luminescent sealing body where the internal temperature becomes high due to plasma, airtightness can be reliably maintained.

[0018] The enclosure can be made of a metallic material. In this case, the sealing pressure of the discharge gas can be further increased. Furthermore, since the enclosure can be formed by machining, manufacturing tolerances can be reduced and manufacturing precision improved. The enclosure can also be made of an insulating material. In this case, the structures held by the enclosure can be easily electrically isolated from each other.

[0019] Alternatively, the first electrode can be fixed to the housing via an insulating component, thus electrically isolating it from the housing. In this case, a voltage independent of the housing's potential can be applied to the first electrode.

[0020] Alternatively, the first electrode may have: a first portion extending along a predetermined direction and serving as part of a first electrode in that predetermined direction; and a second portion located closer to the second electrode than the first portion. The insulating member may have: a main body portion holding the first portion and having a surface extending along a plane perpendicular to the predetermined direction; and a cylindrical portion extending from the surface of the main body portion and surrounding the second portion. In this case, the cylindrical portion can improve the withstand voltage capability of the second portion and suppress discharge between the first electrode and the housing.

[0021] Alternatively, the surface of the main body may be roughened. In this case, the pressure resistance of the surface of the main body can be improved.

[0022] Alternatively, recesses can be formed on the surface of the main body at intervals from both the first electrode and the cylindrical portion. In this case, the generation of unintended discharges can be effectively suppressed.

[0023] Alternatively, a recess can be formed on the surface of the main body in a manner that contacts the first electrode but is spaced apart from the cylindrical portion. In this case, the generation of unintended discharge can be effectively suppressed.

[0024] Alternatively, the first electrode extends along a predetermined direction, and the insulating component has a cover that surrounds a portion of the first electrode in the predetermined direction. In this case, the cover can be used to suppress discharge between the first electrode and the housing.

[0025] Alternatively, the covering portion may have a shape that thins as it approaches the second electrode. In this case, an electric field can be smoothly formed from the first electrode to the insulating component, suppressing discharge caused by disturbances in the electric field.

[0026] Alternatively, the outer peripheral surface of the cover may be roughened. In this case, the withstand voltage of the cover is improved, which can suppress surface discharge at the cover.

[0027] Alternatively, the second electrode can be electrically connected to the enclosure. In this case, the connection to the enclosure allows the second electrode to be at ground potential, eliminating the need for wiring to achieve ground potential.

[0028] Alternatively, the first electrode can be fixed to the housing via a first insulating component, thus electrically isolating it from the housing, and the second electrode can be fixed to the housing via a second insulating component, thus electrically isolating it from the housing. In this case, voltage can be applied to the first and second electrodes separately.

[0029] One aspect of the present invention includes a light source device comprising: the aforementioned light-emitting sealing body; and a light-guiding portion that allows first light to be incident along a first optical axis onto a first opening. According to this light source device, for the reasons stated above, high efficiency and high output can be achieved, and the quality of the output light can be improved.

[0030] Invention Effects

[0031] According to one aspect of the present invention, a light-emitting sealing body and a light source device capable of achieving high efficiency and high output can be provided. Attached Figure Description

[0032] Figure 1 This is a cross-sectional view of the laser excitation source in the implementation method.

[0033] Figure 2 It is along Figure 1 A cross-sectional view of line II-II.

[0034] Figure 3 This is a perspective view of the light-emitting sealing body according to the embodiment.

[0035] Figure 4 It is along Figure 3 A cross-sectional view of line IV-IV.

[0036] Figure 5 It is along Figure 3 A cross-sectional view of the VV line.

[0037] Figure 6 (a) is Figure 5 A magnified view of a portion of the image. Figure 6 (b) is a magnified view of the first variation.

[0038] Figure 7 (a) indicates that in Figure 6 A diagram illustrating an example of the electric field distribution generated by the structure in (a). Figure 7 (b) indicates that in Figure 6 A diagram illustrating an example of the electric field distribution generated by structure (b).

[0039] Figure 8 (a) is a partial enlarged view of the second variation. Figure 8 (b) indicates that in Figure 8 A diagram illustrating an example of the electric field distribution generated by the structure in (a).

[0040] Figure 9 (a) is a magnified view of the third variation. Figure 9 (b) indicates that in Figure 9 A diagram illustrating an example of the electric field distribution generated by the structure in (a).

[0041] Figure 10This is a cross-sectional view of the fourth variation.

[0042] Figure 11 This is a cross-sectional view of the fifth variation.

[0043] Figure 12 This is a cross-sectional view of the sixth variation.

[0044] Figure 13 This is a cross-sectional view of the seventh variation. Detailed Implementation

[0045] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Furthermore, in the following description, the same or equivalent elements will be referred to by the same reference numerals, and repeated descriptions will be omitted.

[0046] [Structure of the laser excitation source]

[0047] like Figures 1-5 As shown, the laser excitation source (source device) 1 includes a light-emitting sealed body 2, a laser source 3, a reflector 4, an optical system 5, and a housing (lamp cover) 6. The light-emitting sealed body 2, laser source 3, reflector 4, and optical system 5 are housed within the housing 6. A discharge gas G1 is sealed within the light-emitting sealed body 2. The discharge gas G1 is, for example, xenon gas. In the laser excitation source 1, plasma is generated in the discharge gas G1. A laser beam, i.e., a first light L1, used to maintain the plasma, is incident on the light-emitting sealed body 2, and light from the plasma, i.e., a second light L2, is emitted from the light-emitting sealed body 2 as output light. The first light has a wavelength of, for example, around 800 nm to 1100 nm. The second light L2 is, for example, light in the mid-infrared region, with a wavelength of around 2 μm to 20 μm. Details regarding the light-emitting sealed body 2 will be described later.

[0048] The laser source 3 is, for example, a laser diode, which outputs a first beam L1 as a laser. A reflector 4 reflects the first beam L1 from the laser source 3 toward an optical system 5. The optical system 5 comprises one or more lenses. The optical system 5 focuses the first beam L1 from the reflector 4 and guides it toward the light-emitting sealing body 2. The laser source 3, the reflector 4, and the optical system 5 constitute a light guide portion R that causes the first beam L1 to be incident along the first optical axis A1 onto the first opening 11. The first opening 11 and the first optical axis A1 will be described later.

[0049] The housing 6 has a main body 61 and a cover member 62. A storage space S1 is formed within the main body 61, and a laser light source 3, a reflector 4, and an optical system 5 are disposed within the storage space S1. A recess 61a is formed in the main body 61, and the opening of the recess 61a is closed (blocked) by the cover member 62, thereby forming a storage space S2. A light-emitting sealing body 2 is disposed within the storage space S2. The main body 61 has a pair of wall portions 611 defining the recess 61a, and each wall portion 611 has an opening 611a through which a second light L2 emitted from the light-emitting sealing body 2 passes. The second light L2 is emitted to the outside through the opening 611a.

[0050] The main body 61 has a wall portion 612 that separates the storage space S1 from the recess 61a, thereby separating the storage space S1 from the storage space S2. Furthermore, an opening 612a is formed in the wall portion 612. A portion of the optical system 5 is disposed within the opening 612a, and a first light L1 is incident on the light-emitting sealing body 2 through the opening 612a.

[0051] A flow path 63 is formed within the cover member 62. Gas G2 flows through the flow path 63. Gas G2 is, for example, an inert gas such as nitrogen. The flow path 63 is connected to the outside via an opening 63a, and gas G2 is supplied to the flow path 63 from an external gas supply device (not shown) via the opening 63a. The flow path 63 is connected to the receiving space S2 of the main body 61 via an opening 63b, and gas G2 flows from the flow path 63 into the receiving space S2 via the opening 63b.

[0052] Gas G2 is discharged to the outside through the vent 613a between the walls 611 and 612 of the main body 61 and the light-emitting sealing body 2, and / or between the cover member 62 and the light-emitting sealing body 2. The vent 613a is a through hole formed in the wall 613 of the main body 61 in a manner that communicates with the storage space S2. The wall 613 has a pair of conical surfaces 613b formed at its boundary with a pair of wall portions 611. The pair of conical surfaces 613b are inclined such that they are closer to each other as they are closer to the vent 613a. Each conical surface 613b is connected to the vent 613a. The conical surfaces 613b guide the gas G2 toward the vent 613a. A through hole 612b is formed in the wall 612 of the main body 61, and a portion of the gas G2 flowing into the storage space S2 from the flow path 63 flows into the storage space S1 through the through hole 612b.

[0053] [Structure of the luminescent sealing body]

[0054] The light-emitting sealing body 2 includes a housing 10, a first window 20, two second windows 30, a first electrode 40, and a second electrode 50.

[0055] The housing 10 is formed of a metal material in a generally box-shaped manner, and houses the discharge gas G1. More specifically, a sealed internal space S3 is formed inside the housing 10, and the internal space S3 is filled with the discharge gas G1. Stainless steel can be cited as an example of the metal material constituting the housing 10. In this case, the housing 10 has light-shielding properties against the first light L1 and the second light L2. That is, the housing 10 is formed of a light-shielding material that prevents the first light L1 and the second light L2 from passing through.

[0056] A first opening 11 and two second openings 12 are formed in the housing 10. A first light L1 is incident on the first opening 11 along a first optical axis A1. The first opening 11 is circular, for example, when viewed from a direction parallel to the first optical axis A1 (hereinafter also referred to as the Z-axis direction). In this example, when viewed from the Z-axis direction, the first optical axis A1 passes through the center of the first opening 11. The first opening 11 includes an inner portion 11a, a middle portion 11b, and an outer portion 11c. The inner portion 11a opens into the internal space S3. The outer portion 11c opens to the outside. The middle portion 11b connects to the inner portion 11a and the outer portion 11c. The inner portion 11a, the middle portion 11b, and the outer portion 11c each have, for example, a cylindrical shape. The diameter (outer shape) of the middle portion 11b is larger than the diameter (outer shape) of the inner portion 11a, and the diameter (outer shape) of the outer portion 11c is larger than the diameter (outer shape) of the middle portion 11b. A portion of the optical system 5 is configured on the outer part 11c.

[0057] The second light L2 is emitted from each of the second openings 12 along the second optical axis A2. Each of the second openings 12 is circular when viewed from a direction parallel to the second optical axis A2 (hereinafter also referred to as the Y-axis direction). In this example, when viewed from the Y-axis direction, the second optical axis A2 passes through the center of the second opening 12. Each of the second openings 12 includes an inner portion 12a, a middle portion 12b, and an outer portion 12c. The inner portion 12a opens into the internal space S3. The outer portion 12c opens to the outside. The middle portion 12b connects to the inner portion 12a and the outer portion 12c. The inner portion 12a, the middle portion 12b, and the outer portion 12c each have, for example, a cylindrical shape. The diameter (outer shape) of the middle portion 12b is larger than the diameter (outer shape) of the inner portion 12a, and the diameter (outer shape) of the outer portion 12c is larger than the diameter (outer shape) of the middle portion 12b.

[0058] The first optical axis A1 intersects the second optical axis A2 within the internal space S3. That is, the first opening 11 and the second opening 12 are arranged such that the first optical axis A1 and the second optical axis A2 intersect each other. The intersection point C of the first optical axis A1 and the second optical axis A2 is located within the internal space S3. In this example, although the first optical axis A1 intersects the second optical axis A2 perpendicularly, the first optical axis A1 can also intersect the second optical axis A2 at an angle other than a right angle. The first optical axis A1 and the second optical axis A2 are not parallel. The first optical axis A1 does not pass through the second opening 12, and the second optical axis A2 does not pass through the first opening 11.

[0059] The first window portion 20 hermetically seals the first opening 11. The first window portion 20 has a first window component 21 and a first frame component 22. The first window component 21 is formed into a circular flat plate shape, for example, from a light-transmitting material that allows the first light L1 to pass through. In this example, the first window component 21 is formed of sapphire, allowing light with wavelengths below 5 μm to pass through.

[0060] The first frame component 22 is formed in a frame shape, for example, from Kovar metal. The first frame component 22 is generally cylindrical in shape. The first frame component 22 has a cylindrical first portion 22a and a cylindrical second portion 22b integrally formed with the first portion 22a. The second portion 22b is larger in shape than the first portion 22a.

[0061] The first window component 21 is disposed within the first portion 22a. Specifically, a circular annular protrusion 22c protruding inward is formed at the boundary between the inner surface of the first portion 22a and the inner surface of the second portion 22b, and the first window component 21 is disposed within the first portion 22a in contact with the protrusion 22c. In this state, the side surface 21a of the first window component 21 is in contact with the inner surface of the first portion 22a.

[0062] The side surface 21a of the first window component 21 is hermetically bonded to the inner surface of the first portion 22a by a bonding material (first bonding material) 23 covering the entire circumference. Thus, the first window component 21 and the first frame component 22 are hermetically sealed. The bonding material 23 is, for example, a metallic solder, more specifically, a titanium-doped silver solder. A titanium-doped silver solder is, for example, a solder composed of 70% silver, 28% copper, and 2% Ti, such as TB-608T from Tokyo Braze Co., Ltd.

[0063] A circular annular flange 22d protruding outward is formed on the outer surface of the second part 22b. The first frame member 22 is fixed to the housing 10 with the flange 22d disposed within the middle part 11b of the first opening 11. In this state, a portion of the first part 22a of the first frame member 22 protrudes from the first opening 11. The first window member 21 is disposed opposite to the intersection point C of the first optical axis A1 and the second optical axis A2. In this example, the light incident surface and the light exit surface of the first window member 21 are flat surfaces extending perpendicularly to the Z-axis direction.

[0064] The first frame component 22 is hermetically fixed to the housing by laser welding. More specifically, the first frame component 22 is hermetically joined to the housing 10 by irradiating the contact portion between the flange 22d and the inner surface of the middle portion 11b of the first opening 11 with a laser from the outside, thus performing welding around the entire circumference. Figure 4 , Figure 5 In the figure, the welded parts are indicated by the reference numeral W. Thus, the first frame component 22 and the housing 10 are airtightly sealed. In this way, the first window component 21 is airtightly joined to the first frame component 22 by the bonding material 23, and is airtightly fixed to the housing 10 via the first frame component 22. By positioning the first frame component 22 between the first window component 21 and the housing 10, adverse conditions caused by the difference in thermal expansion rates between the first window component 21 and the housing 10 can be suppressed.

[0065] Each second window 30 hermetically seals the second opening 12. Each second window 30 has a second window component 31 and a second frame component 32. The second window component 31 is formed into a circular flat plate shape, for example, from a light-transmitting material that allows the second light L2 to pass through. In this example, the second window component 31 is formed of diamond, allowing light with wavelengths below 20 μm to pass through.

[0066] The second frame component 32 is formed into a frame shape, for example, from Kova metal. The second frame component 32 is generally cylindrical in shape. The second frame component 32 has a cylindrical first portion 32a and a cylindrical second portion 32b integrally formed with the first portion 32a. The second portion 32b is larger in shape than the first portion 32a.

[0067] The second window component 31 is disposed within the first portion 32a. Specifically, the first portion 32a has a placement section 32c inside, and the second window component 31 is disposed within the placement section 32c. In this state, a portion of the side surface 31a of the second window component 31 opposite to the intersection point C contacts the inner surface of the first portion 32a. The space within the second frame component 32 also includes: a middle portion 32d connected to the placement section 32c; and an outer portion 32e connected to the middle portion 32d. The middle portion 32d has a frustum-shaped cone with a diameter (outer shape) that increases outwards. The outer portion 32e is formed into a cylindrical shape with a larger diameter (outer shape) than the middle portion 32d.

[0068] The side 31a of the second window component 31 is hermetically bonded to the inner surface of the first portion 32a over its entire circumference by a bonding material (second bonding material) 33. Thus, the second window component 31 and the second frame component 32 are hermetically sealed. The bonding material 33 is, for example, a metallic solder, more specifically, a silver solder doped with titanium.

[0069] A circular annular flange 32f protruding outwards is formed on the outer surface of the second part 32b. The second frame member 32 is fixed to the housing 10 with the flange 32f disposed within the middle part 12b of the second opening 12. In this state, a portion of the first part 32a of the second frame member 32 protrudes from the second opening 12. The second window member 31 is arranged opposite to the intersection point C of the first optical axis A1 and the second optical axis A2. In this example, the light incident surface and the light exit surface of the second window member 31 are flat surfaces extending perpendicularly to the Y-axis direction.

[0070] The second frame component 32 is hermetically fixed to the housing by laser welding. More specifically, the second frame component 32 is hermetically joined to the housing 10 by irradiating the contact portion between the flange portion 32f and the inner surface of the middle portion 12b of the second opening 12 with a laser from the outside to perform welding throughout the entire circumference. Thus, the second frame component 32 and the housing 10 are hermetically sealed. In this way, the second window component 31 is hermetically joined to the second frame component 32 by the bonding material 33, and hermetically fixed to the housing 10 via the second frame component 32. By providing the second frame component 32 between the second window component 31 and the housing 10, adverse conditions caused by the difference in thermal expansion rates between the second window component 31 and the housing 10 can be suppressed.

[0071] The first electrode 40 extends along the X-axis (a predetermined direction) which is perpendicular to both the Y-axis and Z-axis. The first electrode 40 is opposite the second electrode 50 across the intersection point C of the first optical axis A1 and the second optical axis A2. In the X-axis direction, the distance between the intersection point C and the front end of the first electrode 40 is equal to the distance between the intersection point C and the front end of the second electrode 50. The first electrode 40 is formed, for example, of a metallic material such as tungsten. The first electrode 40 is fixed to the housing 10 at its root end via a first insulating member 7, and is electrically isolated from the housing 10. The first electrode 40 is generally rod-shaped. The first electrode 40 has: a first support portion (first part) 41 at its root end; and a first discharge portion (second part) 42 located closer to the front end of the second electrode 50 than the first support portion 41. The first discharge portion 42 is smaller in diameter than the first support portion 41 and has a pointed shape. A tapered portion 42s is formed at the boundary between the first support portion 41 and the first discharge portion 42. The tapered portion 42s has a surface that slopes towards the first support portion 41, with its diameter increasing as it approaches the first support portion 41. The tapered portion 42s is positioned such that a recess (recess) is formed on the surface 71a of the main body portion 71, described later. This configuration of the tapered portion 42s allows the recess to capture electrons E generated at the triple junction (also called a triple junction) P, described later. The first support portion 41 is the middle portion (a portion) of the first electrode 40 in the X-axis direction. The root end 41a of the first support portion 41, opposite to the first discharge portion 42, is formed to be thicker than the portion other than the end 41a. The first discharge portion 42 is formed in a rod shape and is disposed within the housing 10 (i.e., within the internal space S3).

[0072] The first insulating member 7 has a main body portion 71 and a cylindrical portion 72. The first insulating member 7 is formed of an insulating material such as aluminum oxide or ceramic. The main body portion 71 is formed into a cylindrical shape, for example, and holds a first support portion 41 of the first electrode 40. The main body portion 71 has a surface 71a perpendicular to the X-axis direction. The surface 71a is exposed to the internal space S3. An insertion hole 71b is formed on the surface 71a, penetrating the main body portion 71 along the X-axis direction, and the first support portion 41 is disposed and fixed in the insertion hole 71b. The cylindrical portion 72 is formed into a cylindrical shape extending from the surface 71a of the main body portion 71 along the X-axis direction, and surrounds a portion of the first support portion 41 side (root end side) of the first discharge portion 42.

[0073] The end 41a of the first support portion 41 is hermetically bonded to the inner surface of the insertion hole 71b around its entire circumference by a bonding material 43. Thus, the first electrode 40 and the first insulating member 7 are hermetically sealed. The bonding material 43 is, for example, a metallic solder, more specifically, a silver solder doped with titanium.

[0074] The surface 71a of the main body 71 is roughened. In this embodiment, the surface 71a is roughened by forming a recess 73. The recess 73 extends in a circular annular shape surrounding the first discharge portion 42 when viewed from the X-axis direction. The recess 73 is arranged at intervals from both the first electrode 40 and the cylindrical portion 72. The shape of the recess 73 in a cross-section parallel to the X-axis direction is, for example, rectangular.

[0075] The first insulating component 7 is hermetically fixed to the housing 10 via the connecting component 8. A circular annular flange 74 protruding outwards is formed on the outer surface of the main body 71 of the first insulating component 7. The connecting component 8 is made of a metal material such as stainless steel. The connecting component 8 has: a cylindrical first portion 81; and a circular flat plate-shaped second portion 82 extending radially inwards from the first end 81a of the first portion 81. The front end of the second portion 82 contacts the outer surface of the main body 71. The flange 74 contacts both the first portion 81 and the second portion 82.

[0076] The second portion 82 of the connecting member 8 is hermetically bonded to the outer surface of the main body 71 of the first insulating member 7 around its circumference by a bonding material 83. Thus, a hermetically sealed connection is achieved between the connecting member 8 and the first insulating member 7. The bonding material 83 is, for example, a metallic solder, more specifically, a silver solder doped with titanium.

[0077] The connecting component 8 is hermetically fixed to the housing 10 by laser welding. More specifically, a third opening 13 is formed in the housing 10. The cylindrical portion 72 of the first insulating component 7 is disposed within the third opening 13 at a distance from it. The connecting component 8 is disposed such that the second end 81b of the first portion 81 contacts the opening edge of the third opening 13. The connecting component 8 is hermetically joined to the housing 10 by irradiating the contact portion between the first portion 81 and the opening edge of the third opening 13 with a laser from the outside. Thus, the connecting component 8 and the housing 10 are hermetically sealed. In this way, the first insulating component 7 and the connecting component 8 are hermetically joined and hermetically fixed to the housing 10 via the connecting component 8. In this state, the first electrode 40 extends through the third opening 13. The third opening 13 is hermetically sealed by the first electrode 40, the first insulating component 7, and the connecting component 8. The connecting component 8 can also be considered as part of the housing 10.

[0078] The second electrode 50 extends along the X-axis. The front end of the second electrode 50 is opposite the first electrode 40 across the intersection point C of the first optical axis A1 and the second optical axis A2. The second electrode 50 is formed of a metallic material, such as tungsten. The second electrode 50 is electrically connected to the housing 10. The second electrode 50 is generally formed as a rod with a diameter thicker than the first electrode 40. The second electrode 50 has: a second support portion 51 at its root end; and a second discharge portion 52 with a pointed shape, closer to the front end of the first electrode 40 than the second support portion 51. The second support portion 51 is the middle portion (a part) of the second electrode 50 in the X-axis direction. The second discharge portion 52 is formed as a rod and disposed within the housing 10 (i.e., within the internal space S3).

[0079] A fourth opening 14 is formed in the housing 10. A second support portion 51 of the second electrode 50 is disposed within the fourth opening 14 such that its outer surface contacts the inner surface of the fourth opening 14. The second support portion 51 is hermetically bonded to the inner surface of the fourth opening 14 around its entire circumference by a bonding material 53. Thus, the second electrode 50 and the housing 10 are hermetically sealed. The bonding material 53 is, for example, a metallic solder, more specifically, a silver solder doped with titanium.

[0080] A sealing hole 15 is formed in the housing 10 for sealing the discharge gas G1 into the internal space S3. A sealing tube 16 is connected to the sealing hole 15. The sealing tube 16 is formed of a metal material such as copper. The end 16a of the sealing tube 16 opposite to the sealing hole 15 is sealed. A protective member 17 is installed on the sealing tube 16 to cover the sealed end 16a. The protective member 17 is formed of a resin material such as rubber.

[0081] The outer surface of the sealing tube 16 is joined to the inner surface of the sealing hole 15 around its circumference by a bonding material 18. This provides an airtight seal between the sealing tube 16 and the housing 10. The bonding material 18 is, for example, a metallic solder, more specifically, a silver solder doped with titanium. When sealing the discharge gas G1, for example, after introducing the discharge gas G1 into the internal space S3 via the sealing tube 16, the end 16a of the sealing tube 16 is sealed by flattening and cutting it off. Then, a protective component 17 is installed on the sealing tube 16. This direct sealing method is advantageous compared to the trapping method using liquid nitrogen in the following ways: With the trapping method, the window component may deform when the luminescent sealing body is placed in liquid nitrogen. The direct sealing method can suppress this. Furthermore, with the trapping method, deviations in sealing pressure may occur, while the direct sealing method can suppress such deviations. The trapping method is sometimes used when a discharge gas is sealed inside a glass bulb.

[0082] In the light-emitting sealed body 2, the internal space S3 is defined by the housing 10, the first window 20, and the second window 30. The internal space S3 is also defined by the first electrode 40, the second electrode 50, the first insulating component 7, the connecting component 8, and the sealing tube 16. The entire internal space S3 is filled with discharge gas G1. That is, the internal space S3 is filled with discharge gas G1. The discharge gas G1 is in contact with the first window component 21, the first frame component 22, the second window component 31, and the second frame component 32. The sealing pressure (maximum sealing pressure) of the discharge gas G1 is, for example, about 5 MPa (50 atmospheres). The light-emitting sealed body 2 can withstand an internal pressure of more than 15 MPa.

[0083] [Example of laser-excited light source operation]

[0084] In the laser excitation source 1, a voltage application circuit (voltage application unit) (not shown) disposed within the housing 6 is used to ground the second electrode 50, and a negative voltage pulse is applied to the first electrode 40. This causes electrons to be emitted from the first electrode 40 to the second electrode 50. As a result, an arc discharge occurs, generating plasma between the first electrode 40 and the second electrode 50 (at the intersection C). First light L1 from the light guide unit R irradiates this plasma via the first window member 21. This allows the generated plasma to be maintained. Light from the plasma, i.e., second light L2, is emitted as output light through the second window member 31. In the laser excitation source 1, second light L2 is emitted from both second window members 31 in the Y-axis direction. Alternatively, a positive voltage pulse can be applied to the first electrode 40 as a trigger voltage for generating plasma. In this case, electrons are emitted from the second electrode 50 to the first electrode 40.

[0085] [Functions and Effects]

[0086] In the light-emitting sealed body 2, a first electrode 40 and a second electrode 50 are provided opposite each other across the intersection point C of the first optical axis A1 and the second optical axis A2. Therefore, by applying a voltage between the first electrode 40 and the second electrode 50, plasma can be generated between them. The housing 10 is formed of a light-shielding material that prevents the first light L1 and the second light L2 from passing through (transmitting). An internal space S3 is defined by the housing 10, the first window 20, and the second window 30, and the internal space S3 is filled with a discharge gas G1. Therefore, since a high-strength material such as a metal can be selected as the light-shielding material, the sealing pressure of the discharge gas G1 can be increased. As a result, high efficiency and high output can be achieved. Furthermore, since the first light L1 and the second light L2 do not pass through components other than the first window 20 and the second window 30, light loss can be reduced. Therefore, high efficiency and high output can also be achieved. Furthermore, the first opening 11 and the second opening 12 are arranged such that the first optical axis A1 and the second optical axis A2 intersect each other. Therefore, it is possible to suppress the first light L1 from escaping from the second opening 12 and mixing with the second light L2, thereby improving the quality of the output light. Thus, according to the light-emitting sealing body 2, high efficiency and high output can be achieved, and the quality of the output light can be improved.

[0087] The first window component 21 is made of sapphire, and the second window component 31 is made of diamond. Thus, longer wavelengths of light, such as those in the infrared region, can pass through the first window component 21 and the second window component 31.

[0088] The first window component 21 and the second window component 31 are each formed as flat plates. As a result, astigmatism can be suppressed. For example, in a light-emitting seal containing a pair of electrodes arranged in a glass box with a curved surface, astigmatism is generated when laser light and output light pass through the curved surface, but in the light-emitting seal 2, the generation of such astigmatism can be suppressed.

[0089] The first window component 21 is hermetically bonded to the first frame component 22 using a titanium-doped silver solder, and the second window component 31 is hermetically bonded to the second frame component 32 using a titanium-doped silver solder. This allows for a good bond between the first window component 21 and the first frame component 22, and also a good bond between the second window component 31 and the second frame component 32. More specifically, the inventors of this invention discovered that in structures where a diamond-made window component is bonded to a frame component made of Kova metal using undoped silver solder, the silver solder is sometimes repelled and fails to fuse. The inventors of this invention discovered that by using titanium-doped silver solder to bond the window component to the frame component, the silver solder fuses easily, allowing for a good bond between the window component and the frame component.

[0090] The housing 10 is made of a metallic material. This allows for a further increase in the sealing pressure of the discharge gas G1. Furthermore, since the housing 10 can be formed by machining, manufacturing tolerances can be reduced and manufacturing precision can be improved.

[0091] The second electrode 50 is electrically connected to the housing 10. Thus, by connecting to the housing 10, the second electrode 50 can be grounded, eliminating the need for wiring to achieve grounding.

[0092] The first electrode 40 is fixed to the housing 10 via the first insulating component 7 and is electrically isolated from the housing 10. As a result, a voltage independent of the potential (ground potential) of the housing 10 can be applied to the first electrode 40.

[0093] The first insulating member 7 has a main body 71 that holds the first support portion 41 of the first electrode 40, and a recess 73 is formed on the surface 71a of the main body 71. The higher the sealing pressure of the discharge gas G1, the higher the discharge initiation voltage according to Paschen's law. Therefore, it is necessary to increase the voltage applied between the first electrode 40 and the second electrode 50. On the other hand, when the applied voltage is high, electrons generated near the three-way junction where the discharge gas G1, the first insulating member 7, and the first electrode 40 are in contact may cause unintended discharges inside the housing 10. Regarding this, in the light-emitting sealing body 2, a recess 73 is formed on the surface 71a of the main body 71 of the first insulating member 7. This suppresses the movement of electrons generated at the three-way junction along the surface 71a to the cylindrical portion 72, thus suppressing the aforementioned unintended discharges.

[0094] Regarding this point, refer to Figure 6 (a)~ Figure 7 (b) will be explained further. Figure 7 (a) and Figure 7 In (b), the equipotential lines are used to indicate that... Figure 6 (a) and Figure 6 The electric field distribution generated in structure (b). Between the equipotential lines, the potential is lower closer to the equipotential line of the first electrode 40. Figure 7 (a) and Figure 7 In (b), although only the lower side of the figure is shown, the same electric field distribution is generated on the upper side as well. These points are relevant to the following discussion. Figure 8 (b) and Figure 9 (b) is the same.

[0095] exist Figure 6In the first modified example shown in (b), the recess 73 is not formed, and the surface 71a of the main body 71 is flat. Electrons E are easily generated near the three-way junction P where the discharge gas G1, the first insulating component 7, and the first electrode 40 are in contact. Electrons E, therefore... Figure 7 The electric field generated, as shown in (b), causes the electrons to jump and move across the surface of the first insulating member 7, making the surface of the first insulating member 7 positively charged. Electrons are attracted by this positive charge, thereby causing secondary electron multiplication. As a result, the secondary electrons, which increase with acceleration, collide with molecules of the discharge gas G1 on the surface of the first insulating member 7, causing the molecules to ionize, thereby causing surface discharge.

[0096] And such Figure 6 As shown in (a), in the light-emitting sealing body 2, a recess 73 is formed on the surface 71a of the main body portion 71 of the first insulating member 7. Therefore, the recess 73 can capture electrons E generated at the triple junction point P. As a result, it is possible to suppress the movement of electrons E along the surface 71a to the cylindrical portion 72, and to suppress the aforementioned unintended discharge. In the light-emitting sealing body 2, as... Figure 7 An electric field is generated as shown in (a).

[0097] Furthermore, in the light-emitting sealing body 2, the recess 73 is arranged at a distance from both the first electrode 40 and the cylindrical portion 72. This effectively suppresses the generation of unintended discharges.

[0098] [Variation Example]

[0099] exist Figure 8 In the second modification shown in (a), the recess 73 is arranged in a manner that contacts the first electrode 40 but is spaced apart from the cylindrical portion 72. According to the second modification, similarly to the embodiment described above, high efficiency and high output can be achieved, and the quality of the output light can be improved. Furthermore, the recess 73 can capture electrons E generated at the triple junction point P, effectively suppressing the generation of unintended discharges. In the second modification, as... Figure 8 An electric field is generated as shown in (b).

[0100] exist Figure 9In the third variation shown in (a), the first insulating member 7 has a cover 75 that surrounds a portion of the root end side of the first electrode 40 in the X-axis direction. The inner peripheral surface 75b of the cover 75 surrounds a portion of the front end side of the first support 41 and a portion of the root end side of the first discharge portion 42. A gap 75s is formed between the inner peripheral surface 75b and the outer peripheral surface of the first electrode 40, extending to the root end side of the first discharge portion 42. The cover 75 has a shape that thins as it approaches the second electrode 50, and the outer peripheral surface 75a of the cover 75 is a tapered surface. The outer peripheral surface 75a of the cover 75 is roughened. In the third variation, the outer peripheral surface 75a is roughened by forming a plurality of grooves 76 extending around the first electrode 40. The plurality of grooves 76 are arranged along the X-axis direction. Each groove 76 extends in a circular ring shape surrounding the first electrode 40. The groove 76 in the cross section parallel to the X-axis direction has, for example, a semi-circular shape.

[0101] According to the third modification, similarly to the above embodiment, high efficiency and high output can also be achieved, and the quality of the output light can be improved. Furthermore, by utilizing the gap 75s, electrons generated at the three junction points P are less likely to reach the outer peripheral surface 75a of the covering portion 75, and by utilizing the multiple slots 76, the movement of electrons along the outer peripheral surface 75a can be suppressed, thereby suppressing the generation of unintended discharges. That is, in the third modification, as... Figure 9 An electric field is generated as shown in (b). Electrons tend to move in the direction of the equipotential lines (perpendicular to the electric field) and do not easily move along the equipotential lines. Therefore, in the third variation, electrons generated at the three junction points P have difficulty moving along the outer peripheral surface 75a of the covering portion 75.

[0102] exist Figure 10 In the fourth modified example shown, the second electrode 50 is fixed to the housing 10 via the second insulating member 7A and is electrically isolated from the housing 10. The second insulating member 7A is hermetically fixed to the housing 10 via the connecting member 8A. The second insulating member 7A is constructed and connected in the same manner as the first insulating member 7, and the connecting member 8A is constructed and connected in the same manner as the connecting member 8.

[0103] According to the fourth variation, similarly to the above embodiment, high efficiency and high output can also be achieved, and the quality of the output light can be improved. Furthermore, since the second electrode 50 is electrically isolated from the housing 10, voltages can be applied to the first electrode 40 and the second electrode 50 independently. For example, a positive voltage pulse can be applied to the second electrode 50 at the same time a negative voltage pulse is applied to the first electrode 40. In this case, compared to applying only a negative voltage pulse to the first electrode 40, the absolute values ​​of the peak voltages of the negative voltage pulse applied to the first electrode 40 and the positive voltage pulse applied to the second electrode 50 can be reduced. As a result, for example, noise generated when generating negative and positive voltage pulses can be reduced.

[0104] exist Figure 11 In the fifth variation shown, a reflector 91 is disposed inside the housing 10. The reflector 91 is opposite to the first window component 21 across the intersection C of the first optical axis A1 and the second optical axis A2. In the fifth variation, the first light L1 that passes through the plasma and is incident on the plasma from the first window component 21 is focused by the reflector 91 and returned to the plasma. According to the fifth variation, similar to the above embodiment, high efficiency and high output can be achieved, and the quality of the output light can be improved. Furthermore, since the first light L1 that passes through the plasma can be returned to the plasma using the reflector 91, even higher efficiency and high output can be achieved.

[0105] exist Figure 12 In the sixth variation shown, the first window component 21 and the second window component 31 each have a lens shape. According to the sixth variation, similar to the embodiments described above, high efficiency and high output can be achieved, and the quality of the output light can be improved. Furthermore, by enabling the first window component 21 and the second window component 31 to have a lens effect, the beam diameter can be reduced.

[0106] exist Figure 13 In the seventh variation shown, an insulating component (space-restricting component) 93 is disposed within the housing 10. The insulating component 93 is formed into a block shape from an insulating material such as ceramic. The insulating component 93 is disposed in a manner that fills the area outside the optical paths of the first light L1 and the second light L2 within the internal space S3. Figure 13As shown, the first light L1 is focused towards the intersection point C, while the second light L2 diffuses outward from the intersection point C. The insulating member 93 has a first opening 93a for the first light L1 to enter and two second openings 93b for the second light L2 to exit. According to the seventh modification, similar to the above embodiment, high efficiency and high output can also be achieved, and the quality of the output light can be improved. In addition, the generation of leakage current within the housing 10 can be suppressed. Furthermore, since the internal space S3 is filled by the insulating member 93, the convection of the discharge gas G1 in the internal space S3 can be suppressed, and as a result, the flickering of the light-emitting point due to convection can be suppressed.

[0107] This invention is not limited to the embodiments and variations described above. For example, the materials and shapes of each structure are not limited to those described above, and various materials and shapes can be used. The shapes of the first opening 11 and the second opening 12 are not limited to circles, and can be various shapes. The shapes of the first window component 21 and the second window component 31 are not limited to circular plates, and can be various shapes. The roughening of the surface 71a of the main body 71 and / or the outer peripheral surface 75a of the covering 75 is not limited to forming a recess or a groove, but can also be done by forming a protrusion or a combination of protrusions and concave-convex parts. In this invention, "A and / or B" means "at least one of A and B".

[0108] The bonding material 23 can be undoped silver solder, titanium solder, or nickel solder. The same applies to bonding materials 18, 33, 43, 53, and 83. Although two second openings 12 are formed in the above embodiment, only one second opening 12 may be formed, or more than three second openings 12 may be formed. The material constituting the housing 10 can be any light-shielding material that prevents the first light L1 and the second light L2 from passing through (blocks light); it does not necessarily have to be a metallic material, and can also be an insulating material, such as ceramic. The first electrode 40 and the second electrode 50 can be omitted. In this case, plasma can also be generated at the focal point by irradiating the discharge gas G1 with the focused first light L1.

[0109] The first window component 21 may be formed of diamond, and the second window component 31 may be formed of sapphire. Alternatively, both the first window component 21 and the second window component 31 may be formed of sapphire or diamond. When using ultraviolet light, the first window component 21 and / or the second window component 31 may be formed of magnesium fluoride or quartz. The first window component 21 and / or the second window component 31 may be formed of Kova glass.

[0110] The laser source 3 may not be located within the laser excitation source 1. For example, the laser excitation source 1 may replace the laser source 3 with an optical fiber that guides light from an externally located source to a reflector 4. In this case, the optical fiber, the reflector 4, and the optical system 5 constitute a light guide portion R that directs the first light L1 along the first optical axis A1 into the first opening 11.

Claims

1. A luminescent sealing body, comprising: A housing for storing discharge gas, wherein a first opening and a second opening are formed, a first beam of laser light used to maintain plasma generated in the discharge gas is incident along a first optical axis through the first opening, and a second beam of light from the plasma is emitted along a second optical axis through the second opening. The first opening is sealed airtightly, allowing the first light to pass through the first window. The second opening is airtightly sealed, allowing the second light to pass through the second window. and The first and second electrodes are positioned opposite each other across the intersection of the first and second optical axes. The enclosure is formed of a light-shielding material that prevents the first and second light rays from passing through. The internal space is defined by the housing, the first window, and the second window, and the entire internal space is filled with the discharge gas. The first opening and the second opening are configured such that the first optical axis and the second optical axis intersect each other.

2. The light-emitting sealing body according to claim 1, wherein, The first window portion has a first window component that allows the first light to pass through, and the second window portion has a second window component that allows the second light to pass through.

3. The light-emitting sealing body according to claim 2, wherein, The first window component and the second window component are formed of the same material as each other.

4. The luminescent sealing body according to claim 2, wherein, The first window component and the second window component are made of different materials.

5. The luminescent sealing body according to claim 2, wherein, The first window component and the second window component are each formed as a flat plate.

6. The light-emitting sealing body according to claim 2, wherein, The first window component and the second window component are each formed of a material selected from diamond, sapphire, quartz, Korva glass and magnesium fluoride.

7. The light-emitting sealing body according to claim 2, wherein, The first window portion also has a first frame component that is airtightly fixed to the housing, and the second window portion also has a second frame component that is airtightly fixed to the housing. The first window component is hermetically joined to the first frame component using a first bonding material, and the second window component is hermetically joined to the second frame component using a second bonding material.

8. The luminescent sealing body according to claim 7, wherein, The first bonding material and the second bonding material are each metal solder.

9. The luminescent sealing body according to claim 8, wherein, The metal solder is a silver solder doped with titanium.

10. The light-emitting sealing body according to claim 1, wherein, The enclosure is made of metal.

11. The light-emitting sealing body according to claim 1, wherein, The enclosure is made of insulating material.

12. The light-emitting sealing body according to claim 10, wherein, The first electrode is fixed to the housing via an insulating component and is electrically isolated from the housing.

13. The light-emitting sealing body according to claim 12, wherein, The first electrode has: a first portion extending along a predetermined direction and being part of the first electrode in the predetermined direction; and a second portion located closer to the second electrode than the first portion. The insulating component has: a main body portion that holds the first portion and has a surface extending along a plane perpendicular to the predetermined direction; and a cylindrical portion extending from the surface of the main body and surrounding the second portion.

14. The light-emitting sealing body according to claim 13, wherein, The surface of the main body has been roughened.

15. The light-emitting sealing body according to claim 14, wherein, A recess is formed on the surface of the main body portion, spaced apart from both the first electrode and the cylindrical portion.

16. The light-emitting sealing body according to claim 14, wherein, A recess is formed on the surface of the main body portion in such a way that it contacts the first electrode but is spaced apart from the cylindrical portion.

17. The luminescent sealing body according to claim 12, wherein, The first electrode extends along a predetermined direction. The insulating component has a cover that surrounds a portion of the first electrode in the specified direction.

18. The luminescent sealing body according to claim 17, wherein, The covering portion has a shape that thins as it approaches the second electrode.

19. The light-emitting sealing body according to claim 18, wherein, The outer peripheral surface of the cover has been roughened.

20. The light-emitting sealing body according to claim 10, wherein, The second electrode is electrically connected to the housing.

21. The light-emitting sealing body according to claim 10, wherein, The first electrode is fixed to the housing via a first insulating component, and is electrically isolated from the housing. The second electrode is fixed to the housing via a second insulating component and is electrically isolated from the housing.

22. The light-emitting sealing body according to claim 1, wherein, At least one of the first electrode and the second electrode is led out of the casing.

23. The luminescent sealing body according to claim 1, wherein, The first light incident from the first window directly enters the plasma, while the second light from the plasma directly passes through the second window.

24. A light source device, comprising: The light-emitting sealing body according to claim 1; and A light guide section that directs the first light along the first optical axis into the first opening.

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