Laser beam expander with adjustable collimation
AssigneeThe United States of America as represented by the Administrator of the National Aeronautics and Space Administration
InventorsLuis A. Ramos-Izquierdo, Xiaoli Sun
Life of this patent
Estimating the term…
Abstract
A laser beam expander has at least two negative lenses with adjustable collimation. The amount of required motion can be reduced by an order of magnitude over single negative lens approaches by splitting the input lens in two and adjusting the small remaining air gap between the lenses. The change in collimation may be accomplished by heating/cooling (i.e., thermal), mechanical motion (e.g., motors), electro-optical means (e.g., applying or reducing an electric current), any combination thereof, or any other suitable mechanism.
Claims18
An apparatus, comprising:
- a first negative lens configured to receive a laser beam;
- and
- a second negative lens positioned after the first negative lens in a path of the laser beam such that a gap exists between the first negative lens and the second negative lens, wherein
- changing a size of the gap changes collimation of the laser beam when output by the second negative lens;
- and
- the first negative lens, the second negative lens, or both, are moved by any combination of thermal, mechanical, and/or electro-optical mechanisms;
- and
- a concave surface of the first negative lens most proximate to a convex surface of the second negative lens have matching curvatures.
A Galilean laser beam expander, comprising:
- a plurality of negative lenses configured to receive a laser beam, each of the plurality of lenses having a gap between itself and a lens earlier in a path of the laser beam except for a first negative lens in the path, and
- a concave surface of the first negative lens most proximate to a convex surface of the second negative lens have matching curvatures, wherein
- changing sizes of one or more gaps between pairs of the plurality of negative lenses changes collimation of the laser beam when output by a last negative lens in the path of the laser beam.
A laser beam expander, comprising:
- a first negative lens configured to receive a laser beam;
- a second negative lens positioned after the first negative lens in a path of the laser beam such that a gap exists between the first negative lens and the second negative lens;
- a first tube connected to the first negative lens or the second negative lens;
- and
- a heating element that provides heat to the first tube, the heating element configured to heat the first tube such that applying heat decreases a size of the gap via thermal expansion, wherein
- changing the size of the gap changes the collimation of the laser beam when output by the second negative lens.
Dependencies are inferred from the claim text.