Light emitting device and light emitting module

{
  "publication_number": "US2026106431A1",
  "country": "US",
  "kind": "A1",
  "title": "Light emitting device and light emitting module",
  "abstract": "A light-emitting device includes: a base having a mounting surface; a plurality of semiconductor laser elements each configured to emit a laser beam from a light emission surface in a first direction, which are arranged on the mounting surface in a second direction; a plurality of first mirror members each having a first reflective surface configured to reflect the laser beam emitted from a corresponding one of the plurality of semiconductor laser elements to change a travel direction of the laser beam into a direction away from the mounting surface; a cover configured to transmit the laser beams reflected by the first reflective surfaces; and at least one second mirror member arranged on an upper surface of the cover, and having a second reflective surface configured to reflect the laser beams transmitted through the cover to further change the travel directions of the laser beams.",
  "claims": [
    "1. A light-emitting device comprising: a base having a mounting surface; a plurality of semiconductor laser elements each having a light emission surface and being configured to emit a laser beam from the light emission surface in a first direction, the plurality of semiconductor laser elements arranged on the mounting surface in a second direction intersecting the first direction; a plurality of first mirror members each having a first reflective surface configured to reflect the laser beam emitted from a corresponding one of the plurality of semiconductor laser elements to change a travel direction of the laser beam into a direction away from the mounting surface; a cover having a lower surface facing the mounting surface and an upper surface on a side opposite to the lower surface, the cover positioned above the plurality of semiconductor laser elements and the plurality of first mirror members, the cover configured to transmit the laser beams reflected by the first reflective surfaces; and at least one second mirror member arranged on the upper surface of the cover, and having a second reflective surface configured to reflect the laser beams transmitted through the cover to further change the travel directions of the laser beams, wherein: the plurality of first mirror members are arranged on the mounting surface such that positions in the first direction of the first reflective surfaces are different from each other, and with the mounting surface serving as a reference plane, heights, from the reference plane, of optical axes of the laser beams reflected by the second reflective surface are different from each other. 2. The light-emitting device according to claim 1, wherein: a plurality of distances, each defined as a distance between a respective one of the plurality of first mirror members and a corresponding one of the plurality of semiconductor laser elements, are substantially the same. 3. The light-emitting device according to claim 1, wherein: the mounting surface on which the plurality of semiconductor laser elements are mounted extends in a single plane. 4. The light-emitting device according to claim 1, wherein: the plurality of first mirror members are arranged along the second direction so as to be gradually shifted in the first direction or in a direction opposite to the first direction. 5. The light-emitting device according to claim 2, further comprising: a plurality of housings arranged on the mounting surface, wherein: each of the plurality of housings houses a respective one of the plurality of semiconductor laser elements, and a corresponding one of the plurality of first mirror members corresponding to the respective one of the plurality of semiconductor laser elements. 6. The light-emitting device according to claim 1, further comprising: a plurality of fast-axis collimating lenses positioned between the mounting surface of the base and the lower surface of the cover, wherein: each of the plurality of fast-axis collimating lenses is configured to collimate, in a fast-axis direction, the laser beam emitted from a corresponding one of the plurality of semiconductor laser elements. 7. The light-emitting device according to claim 1, further comprising: a plurality of slow-axis collimating lenses arranged on the upper surface of the cover, wherein: each of the plurality of slow-axis collimating lenses is configured to collimate, in a slow-axis direction, the laser beam emitted from a corresponding one of the plurality of semiconductor laser elements and reflected by the first reflective surface and the second reflective surface sequentially in this order. 8. The light-emitting device according to claim 7, wherein: the plurality of slow-axis collimating lenses are formed in a monolithic body. 9. The light-emitting device according to claim 1, wherein: the base includes a region formed of a material having a thermal conductivity of 10 W/m·K to 2000 W/m·K. 10. The light-emitting device according to claim 1, wherein: the plurality of semiconductor laser elements are hermetically sealed by the base and the cover. 11. The light-emitting device according to claim 1, wherein: the absolute value of a difference in height from the mounting surface between the optical axes of two adjacent ones of a plurality of laser beams that have been emitted from the plurality of semiconductor laser elements and then reflected by the first reflective surfaces and the second reflective surface sequentially in this order is in a range of 0.3 mm to 0.5 mm. 12. A light-emitting device comprising: a plurality of sub-light-emitting devices each of which is the light-emitting device according to claim 1, wherein: the plurality of sub-light-emitting devices are arranged in the first direction, and the plurality of sub-light-emitting devices share the base and the cover. 13. A light-emitting device comprising: a base having a mounting surface; a plurality of first semiconductor laser elements each having a first light emission surface and being configured to emit a laser beam from the light emission surface in a first direction, the plurality of first semiconductor laser elements arranged on the mounting surface in a second direction intersecting the first direction; a plurality of second semiconductor laser elements each having a second light emission surface and being configured to emit a second laser beam from the light emission surface in the first direction, and arranged on the mounting surface in the second direction; a plurality of first mirror members each having a first reflective surface configured to reflect the first laser beam emitted from a corresponding one of the plurality of first semiconductor laser elements to change a travel direction of the first laser beam into a direction away from the mounting surface; a plurality of third mirror members each having a third reflective surface configured to reflect the second laser beam emitted from a corresponding one of the plurality of second semiconductor laser elements to change a travel direction of the second laser beam into a direction away from the mounting surface; a cover having a lower surface facing the mounting surface and an upper surface on a side opposite to the lower surface, the cover positioned above the plurality of first semiconductor laser elements, the plurality of first mirror members, the plurality of second semiconductor laser elements, and the plurality of third mirror members, the cover configured to transmit the first laser beams reflected by the first reflective surfaces and the second laser beams reflected by the third reflective surfaces; a second mirror member arranged on the upper surface of the cover, and having a second reflective surface configured to reflect the first laser beams transmitted through the cover to further change the travel directions of the first laser beams; and a fourth mirror member arranged on the upper surface of the cover, at a location further in a direction opposite to the first direction than the second mirror member, the fourth mirror member having a fourth reflective surface configured to reflect the second laser beams transmitted through the cover to further change the travel directions of the second laser beams, wherein: the plurality of second semiconductor laser elements are arranged at a location further in the direction opposite to the first direction than the plurality of first semiconductor laser elements, the plurality of first mirror members are arranged on the mounting surface such that positions in the first direction of the first reflective surfaces are different from each other, the plurality of third mirror members are arranged on the mounting surface such that positions in the first direction of the third reflective surfaces are different from each other, and the plurality of third mirror members are arranged at locations further in the direction opposite to the first direction than the plurality of first mirror members. 14. A light-emitting module comprising: the light-emitting device according to claim 1; a plurality of fifth mirror members each having a fifth reflective surface configured to reflect, in a third direction, the laser beam emitted from a corresponding one of the semiconductor laser elements and reflected by the first reflective surface and the second reflective surface sequentially in this order; and a condensing lens configured to couple, to an optical fiber, a plurality of laser beams that have been emitted from the plurality of semiconductor laser elements and then reflected by the first reflective surface, the second reflective surface, and the fifth reflective surface sequentially in this order. 15. A light-emitting module comprising: the light-emitting device according to claim 13; a plurality of fifth mirror members each having a fifth reflective surface configured to reflect, in a third direction, the first laser beam emitted from a corresponding one of the first semiconductor laser elements and reflected by the first reflective surface and the second reflective surface sequentially in this order; a plurality of sixth mirror members each having a sixth reflective surface configured to reflect, in the third direction, the second laser beam emitted from a corresponding one of the second semiconductor laser elements and reflected by the third reflective surface and the fourth reflective surface sequentially in this order; and a condensing lens configured to couple, to an optical fiber, a plurality of first laser beams that have been emitted from the plurality of first semiconductor laser elements and then reflected by the first reflective surface, the second reflective surface, and the fifth reflective surface sequentially in this order, and a plurality of second laser beams that have been emitted from the plurality of second semiconductor laser elements and then reflected by the third reflective surface, the fourth reflective surface, and the sixth reflective surface sequentially in this order. 16. The light-emitting module according to claim 15, wherein: the second laser beam emitted from each of the plurality of second semiconductor laser elements has the same polarization direction as that of the first laser beam emitted from each of the plurality of first semiconductor laser elements, and the light-emitting module further comprises: a half-wave plate arranged on optical paths of the plurality of first laser beams or optical paths of the plurality of second laser beams; and a polarizing beam splitter configured to direct the plurality of first laser beams that have been transmitted through the half-wave plate and the plurality of second laser beams that have not been transmitted through the half-wave plate toward the condensing lens, or direct the plurality of second laser beams that have been transmitted through the half-wave plate and the plurality of first laser beams that have not been transmitted through the half-wave plate toward the condensing lens."
  ],
  "description_excerpt": "The present disclosure relates to light-emitting devices and light-emitting modules.\n\nA technique for increasing the power of laser light by combining a plurality of laser beams emitted from a plurality of semiconductor laser elements has in recent years been developed. Japanese Patent Publication No. 2018-530768 discloses an example laser system capable of implementing such high-power laser light.\n\nThere has been a demand for a light-emitting device that includes a plurality of semiconductor laser elements, and that effectively dissipates, out of the light-emitting device, heat generated by the plurality of semiconductor laser elements during driving.\n\nA light-emitting device according to one embodiment of the present disclosure includes: a base having a mounting surface; a plurality of semiconductor laser elements each having a light emission surface from which a laser beam is emitted in a first direction, the plurality of semiconductor laser elements arranged on the mounting surface in a second direction intersecting the first direction; a plurality of first mirror members each having a first reflective surface configured to reflect the laser beam emitted from a corresponding one of the plurality of semiconductor laser elements to change the travel direction of the laser beam into a direction away from the mounting surface; a cover having a counter surface facing the mounting surface and an upper surface on a side opposite to the counter surface, the cover positioned ...",
  "cpc": [
    "H01S 5/02255",
    "H01S 5/02208",
    "H01S 5/02253",
    "H01S 5/02315"
  ],
  "assignees": [
    "Nichia Corp",
    "Furukawa Electric Co Ltd"
  ],
  "inventors": [
    "Toshiaki Yamashita"
  ],
  "filing_date": "2023-09-20",
  "publication_date": "2026-04-16",
  "priority_date": "2022-09-29",
  "application_number": "US-202319115956-A",
  "cited_by_count": 0
}