Patent ID: 9436012
Filing Date: 2016-09-06
CPC Classification: B23K,G02B

Claim Text:
1. A dual-focus optical conversion unit, comprising: a beam splitter (BS) that is placed at angle to an incident laser beam, and is adapted to split an incident beam into two beams having a similar polarization as the incident beam, a reflected beam and a transferred beam; and a convex mirror (CM) placed beyond and parallel to the BS, wherein the surface of the CM is coated with a reflective phase-retarder coating, and is placed substantially close to the BS; wherein the dual-focus optical conversion unit is configured to split the incident-laser beam into two beams, a R-beam reflected from the BS; and a D-beam that pass through the BS and is reflected and changed polarization by the coated surface of the CM and returns via the BS, wherein the R-beam and the D-beam have different polarizations and propagates along a substantial similar optical axis, wherein the R-beam and the D-beam differ in their divergence value, and wherein the power of the beam incident on the convex mirror (CM) is in the range of 20% to 50% of the power of the incident laser beam.