Microsoft Corporation
DICHROIC COATINGS TO IMPROVE DISPLAY UNIFORMITY AND LIGHT SECURITY IN AN OPTICAL COMBINER

Abstract:

Reflectors comprising thin film dichroic coatings are located on various components of a waveguide-based optical combiner in a see-through display of a head-mounted display (HMD) device to reduce color cross-coupling in holographic images and reflect forward-projected holographic image light back to a user's eye. The dichroic coatings implement narrowband reflectors for each of one or more colors of an RGB (red, green, blue) color model over the angular range associated with the field of view (FOV) of the virtual portion of the see-through display. Utilization of the dichroic coatings can improve virtual display uniformity and lessen sharp edge defects by reducing cross-coupling and may also improve light security by reducing the forward-projected holographic image light that escapes from the HMD device.