Patent attributes
An illuminator includes a semiconductor emitter chip, e.g. a VCSEL chip, configured for emitting a light beam. A polarization-selective element is optically coupled to the semiconductor emitter chip for defining a polarization state of the emitted light beam. A beam redirecting optic is coupled to the polarization-selective element for receiving and at least one of collimating or redirecting the emitted light beam. The polarization-selective element, e.g. a polarization-selective optical feedback element for VCSEL, defines a polarization state of the emitted light beam, thereby stabilizing output optical power of light beam propagated through the beam redirecting optic. A light beam of a constant optical power and a well-defined polarization state may be used as an illumination source for an eye-tracking system.
