US 2016/0259174 A1 · POLARIZATION-CONTROLLED LASER LINE-PROJECTOR

Abstract

In a laser line projection apparatus, six spaced-apart unpolarized laser-beams are plane-polarized with low loss by a combination of a thin-film polarizer, a reflector, and two polarization rotators. Two beams are polarized in each of three polarization-orientations. Two of the polarization-orientations are orthogonally aligned with each other in P and S orientations. The other polarization-orientation is non-orthogonally aligned in an intermediate orientation. The beams are intensity-homogenized and projected into a line of radiation. Any point on the line of radiation is formed from rays with an angular distribution of polarization-orientation from S to P through the intermediate orientation and back to S through the intermediate orientation.

Claims14

Dependent claims

Optical apparatus, comprising:

a plurality of polarizers arranged to receive a corresponding plurality of laser-beams and plane-polarize the laser-beams;
the polarizers being configured such that at least two of the laser-beams are plane-polarized with different polarization-orientations;
and
a plurality of optical elements configured and arranged to project the plane-polarized laser-beams on a workpiece as a line of laser radiation with rays from each of the laser-beams incident at different angles on any point on the line, with the polarization-orientation of the rays varying with angle-of-incidence in a predetermined manner.

1 more element

An apparatus for projecting three laser beams into a line focus on a work piece, said three laser beams being aligned in an array with the second beam being between the first and third beams, said apparatus comprising:

a first set of polarization optics for receiving the first laser beam, said first set of polarization optics including a partially transmitting polarizer and one polarization rotator, said partially transmitting polarizer for transmitting P-polarized light and reflecting S-polarized light and wherein the said polarization rotator is positioned to rotate the transmitted portion of the light by ninety degrees;
a second set of polarization optics for receiving the third laser beam, said second set of polarization optics including a partially transmitting polarizer and one polarization rotator, said partially transmitting polarizer for transmitting P-polarized light and reflecting S-polarized light and wherein the said polarization rotator is positioned to rotate the reflected portion of the light by ninety degrees;
a third set of polarization optics, located between the first and third sets and receiving the second laser beam, said third set of polarization optics including a partially transmitting polarizer and first and second polarization rotators, said partially transmitting polarizer for transmitting P-polarized light and reflecting S-polarized light, wherein the first polarization rotator is positioned to rotate the transmitted portion of the light by 45 degrees and the second polarization rotator is positioned to rotate the reflected portion of the light by 45 degrees;
and
a lens system for receiving the polarized beams and arranged to project the beam along a line focus on the work piece, said polarization optics and lens system arranged such that at each location along the line focus, the light rays with the lowest angle of incidence are P-polarized and the light rays with the highest angle of incidence are S-polarized and the light rays with intermediate angles of incidence have an intermediate polarization orientation.

2 more elements

Dependencies are inferred from the claim text.

Polarization-controlled laser line-projector

Life of this patent

Polarization-controlled laser line-projector

Life of this patent

Abstract

Claims14