Laser module and system
Laser modules and systems are provided that are smaller, lighter, and less complex and while more reliably generating collimated laser beams having limited divergence.
1. A laser module, comprising:
a base;
a housing connected to the base and including a window, the housing, the window, and the base defining a sealed environment of the laser module;
a semiconductor laser supported on the base and disposed within the sealed environment, the semiconductor laser being configured to emit a divergent beam, in a first direction, from the sealed environment and via the window;
a frame having a first segment and a second segment connected to the first segment, the first segment:
having a first end joined to the base,
having a second end opposite the first end and moveable relative to the base, and
extending from the base, in the first direction, beyond the window; and
a collimating lens positioned to receive the divergent beam from the window, the lens being mounted on the second segment, wherein:
the first segment is configured to expand, in the first direction, at a rate of thermal expansion over a range of temperatures,
the second segment is configured to expand, in a second direction opposite the first direction, at the rate of thermal expansion over the range of temperatures, and
the frame is configured to maintain the lens positioned within a range of positions about a focal length of the lens over the range of temperatures.
2. The laser module of claim 1 , wherein the base includes a front side forming a portion of the sealed environment, and a header disposed within the sealed environment, the header extending from the first side in the first direction.
3. The laser module of claim 2 , further comprising a submount joined to the header, the semiconductor laser being mounted to the header by way of the submount.
4. The laser module of claim 1 , wherein the semiconductor laser comprises a quantum cascade laser, and the divergent beam has a wavelength between 2μ and 30μ.
5. The laser module of claim 1 , further comprising a plurality of conductors connected to the semiconductor laser, at least one conductor of the plurality of conductors extending through the base, from within the sealed environment, in the second direction.
6. The laser module of claim 5 , further comprising a nonconductive sealed opening in the base, the at least one conductor of the plurality of conductors extending through the base via the nonconductive sealed opening.
7. The laser module of claim 1 , wherein the focal length of the lens is greater than 10 mm.
8. The laser module of claim 1 , wherein:
the first segment comprises a first material having a first coefficient of thermal expansion, and
the second segment comprises a second material different from the first material, the second material having a second coefficient of thermal expansion different from the first coefficient of thermal expansion.
9. The laser module of claim 1 , wherein the second segment is connected to the second end of the first segment, the second segment extending, from the second end, in the second direction toward the window.
10. The laser module of claim 1 , wherein the first and second directions extend substantially parallel to an optical axis of the lens.
11. The laser module of claim 1 , wherein:
the first segment is configured to expand a first distance, in the first direction, over the range of temperatures, and
the second segment is configured to expand a second distance less than the first distance, in the second direction, over the range of temperatures.
12. A laser module, comprising:
a base;
a semiconductor laser supported on the base, the semiconductor laser being configured to emit a divergent beam, in a first direction, away from the base;
a frame extending from the base, the frame having a first segment and a second segment connected to the first segment; and
a collimating lens supported on the frame and positioned to receive the divergent beam from the semiconductor laser, wherein:
the first segment is configured to expand, in the first direction, at a rate of thermal expansion over a range of temperatures,
the second segment is configured to expand, in a second direction opposite the first direction, at the rate of thermal expansion over the range of temperatures, and
the frame is configured to maintain the lens positioned within a range of positions about a focal length of the lens over the range of temperatures.
13. The laser module of claim 12 , wherein the first segment includes a first end joined to the base, and a second end opposite the first end and moveable relative to the base, the second segment being joined to the second end of the first segment.
14. The laser module of claim 12 , wherein:
the second segment includes a first end joined to the base, and a second end opposite the first end and moveable relative to the base; and
the first segment includes a first end joined to the second end of the second segment, and a second end moveable relative to the second segment, the lens being mounted on the first segment proximate the second end of the first segment.
15. The laser module of claim 12 , further comprising a housing connected to the base,
the housing and the base defining a sealed environment of the laser module, and
the semiconductor laser being disposed within the sealed environment.
16. The laser module of claim 15 , further comprising a plurality of conductors connected to the semiconductor laser, at least one conductor of the plurality of conductors extending through the base, from within the sealed environment, in the second direction.
17. The laser module of claim 12 , wherein:
the focal length of the lens is greater than 10 mm,
the first segment is configured to expand a first distance, in the first direction, over the range of temperatures, and
the second segment is configured to expand a second distance less than the first distance, in the second direction, over the range of temperatures.
18. A method of manufacturing a laser module, the method comprising:
providing a base;
mounting a semiconductor laser on the base, the semiconductor laser being configured to emit a divergent beam, in a first direction, away from the base;
connecting a frame to the base, the frame having a first segment and a second segment connected to the first segment; and
mounting a collimating lens on the frame at a location optically downstream of the semiconductor laser, the lens being having a focal length greater than 10 mm and being positioned to receive the divergent beam from the semiconductor laser, wherein:
the first segment is configured to expand, in the first direction, at a rate of thermal expansion over a range of temperatures,
the second segment is configured to expand, in a second direction opposite the first direction, at the rate of thermal expansion over the range of temperatures, and
the frame is configured to maintain the lens positioned within a range of positions about the focal length of the lens over the range of temperatures.
19. The method of claim 18 , further comprising connecting a plurality of conductors to the semiconductor laser, at least one conductor of the plurality of conductors extending through the base, from proximate the semiconductor laser, in the second direction.
20. The method of claim 18 , wherein:
the first segment comprises a first material having a first coefficient of thermal expansion, and
the second segment comprises a second material different from the first material, the second material having a second coefficient of thermal expansion different from the first coefficient of thermal expansion.