Semiconductor laser module
AssigneePantec Engineering AG
InventorsArne Heinrich, Clemens Hagen
Life of this patent
Estimating the term…
Abstract
A semiconductor laser module (10) comprises a tapered laser diode (12) and/or a tapered amplifier diode equipped with beam shaping optics (14). The tapered laser diode and/or the tapered amplifier diode includes an emission facet (16) for emitting a laser beam (18) along a beam axis (24). The beam-shaping optics comprise a plano-convex cylindrical lens oriented so as to change divergence of the beam in the fast axis direction, the plano-convex spherical cylindrical lens having a planar surface (26) arranged facing the facet and a circular cylindrical surface (22) facing away from the facet.
Claims16
A semiconductor laser module, comprising at least one of a tapered laser diode and a tapered amplifier diode, including an emission facet for emitting a laser beam along a beam axis, said laser beam having a beam quality factor in fast axis direction, hereinafter denoted Mf2, and a beam quality factor in slow axis direction, hereinafter denoted Ms2;
- and
- beam shaping optics;
- wherein said beam-shaping optics comprise a plano-convex cylindrical lens oriented so as to change divergence of said beam in fast axis direction, said plano-convex cylindrical lens having a planar surface arranged facing said facet a circular cylindrical surface facing away from said facet and a refractive index, hereinafter denoted n, chosen such that the condition
- 93
-
- %
- ·
- sin
-
-
- u
- f
- /
- sin
- (
- u
- s
- ·
- M
- f
- 2
- M
- s
- 2
- )
- ≤
- n
- ≤
- 107
-
- %
- ·
- sin
-
-
- u
- f
- /
- sin
- (
- u
- s
- ·
- M
- f
- 2
- M
- s
- 2
- )
- ,
- where uf denotes the uncorrected 1/e2 fast axis divergence half-angle of said laser beam and us denotes the uncorrected 1/e2 slow axis divergence half-angle of said laser beam, is satisfied.
A semiconductor laser module, comprising at least one of a tapered laser diode and a tapered amplifier diode, including an emission facet for emitting a laser beam along a beam axis, said laser beam having a beam quality factor in fast axis direction, hereinafter denoted Mf2, and a beam quality factor in slow axis direction, hereinafter denoted Ms2;
- and
- beam shaping optics;
- wherein said beam-shaping optics comprise a plano-convex cylindrical lens positioned directly in front of the emission facet and oriented so as to reduce divergence of said beam in fast axis direction, said plano-convex cylindrical lens having a planar surface arranged facing said facet, and a circular cylindrical surface facing away from said facet, and
- wherein circular cylindrical surface has a radius of curvature chosen such that said divergence of said beam in fast axis direction is reduced to match the product of divergence of said beam in slow axis direction and the ratio Mf2/Ms2 wherein the plano-convex cylindrical lens has a refractive index n chosen such that the condition
- 93
-
- %
- ·
- sin
-
-
- u
- f
- /
- sin
-
-
- (
- u
- s
- ·
- M
- f
- 2
- M
- s
- 2
- )
- ≤
- n
- ≤
- 107
-
- %
- ·
- sin
-
-
- u
- f
- /
- sin
-
-
- (
- u
- s
- ·
- M
- f
- 2
- M
- s
- 2
- )
- ,
- where ur denotes the uncorrected 1/e2 fast axis divergence half-angle of said laser beam us denotes the uncorrected 1/e2 slow axis divergence half-angle of said laser beam, is satisfied.
A semiconductor laser module, comprising at least one of a tapered laser diode and a tapered amplifier diode, including an emission facet for emitting a laser beam along a beam axis, said laser beam having a beam quality factor in fast axis direction, hereinafter denoted Mf2, and a beam quality factor in slow axis direction, hereinafter denoted Ms2, said laser beam having a first virtual source from which said laser beam appears to diverge in fast axis direction and a second virtual source from which said laser beam appears to diverge in slow axis direction, said second virtual source being located farther away from the emission facet than said first virtual source;
- and
- beam shaping optics;
- wherein said beam-shaping optics comprise a plano-convex cylindrical lens positioned directly in front of the emission facet and oriented so as to change divergence of said beam in fast axis direction, said plano-convex cylindrical lens having a planar surface arranged facing said facet, a circular cylindrical surface facing away from said facet;
- and
- wherein the plano-convex cylindrical lens is configured and arranged to satisfy the aplanatic condition in such a way that a virtual image of the first virtual source by the plano-convex cylindrical lens substantially coincides with the second virtual source wherein the plano-convex cylindrical lens has a refractive index n chosen such that the condition
- 93
-
- %
- ·
- sin
-
-
- u
- f
- /
- sin
-
-
- (
- u
- s
- ·
- M
- f
- 2
- M
- s
- 2
- )
- ≤
- n
- ≤
- 107
-
- %
- ·
- sin
-
-
- u
- f
- /
- sin
-
-
- (
- u
- s
- ·
- M
- f
- 2
- M
- s
- 2
- )
- ,
- where ur denotes the uncorrected 1/e2 fast axis divergence half-angle of said laser beam us denotes the uncorrected 1/e2 slow axis divergence half-angle of said laser beam, is satisfied.
Dependencies are inferred from the claim text.