Light Source with Controllable Linear Polarization

摘要

A light source having first and second wire-grid polarizers and a laser that emits a beam of linearly polarized light that is characterized by a propagation direction is disclosed. The first wire-grid polarization filter is characterized by a first linear polarization pass direction and a first actuator for causing the first linear polarization pass direction to rotate relative to the beam of linearly polarized light. The second wire-grid polarization filter is characterized by a second linear polarization pass direction and a second actuator for causing the second linear polarization pass direction to rotate relative to the beam of linearly polarized light. A controller sets the first and second linear polarization pass directions to provide linearly polarized light having a specified polarization direction.

主权项

1. A light source comprising:
a first laser that emits a beam of linearly polarized light that is characterized by a propagation direction; a first wire-grid polarization filter characterized by a first linear polarization pass direction and a first actuator for causing said first linear polarization pass direction to rotate relative to said beam of linearly polarized light, said first wire-grid polarization filter being positioned such that said beam of linearly polarized light passes through said first wire-grid polarization filter; a second wire-grid polarization filter characterized by a second linear polarization pass direction and a second actuator for causing said second linear polarization pass direction to rotate relative to said beam of linearly polarized light, said second wire-grid polarization filter being positioned such that said beam of linearly polarized light passes through said second wire-grid polarization filter after passing through said first wire-grid polarization filter; and a controller for setting said first and second linear polarization pass directions to provide linearly polarized light having a specified polarization direction, said first linear polarization pass direction being different from said second linear polarization pass direction for at least one value of said specified polarization value.