Waveguide combiner with reduced light leakage

A head-mounted display (HMD) device wearable by a user and supporting a mixed-reality experience comprising a display of virtual images for objects in a virtual world and real-world images for objects in a real world, comprising:

• a visor;
• a display engine generating virtual image light for the virtual images;
• a waveguide combiner comprising a see-through waveguide having an eye-facing side and a real-world-facing side, an input coupler disposed on the waveguide configured for in-coupling the virtual image light from the display engine into the waveguide, and an output coupler disposed on the waveguide for out-coupling the virtual images from the waveguide to an eye of the user, wherein the waveguide combiner includes a see-through portion, located on the HMD device in front of the eye of the user when the HMD device is donned, through which the user views the real world;
• and
• a light deflector disposed along a forward-propagating light path extending from the output coupler of the waveguide combiner towards the real world, wherein the light deflector steers forward-propagating virtual image light to impart an angular change in a propagation direction of the virtual image light to change the propagation direction to be away from the eye of the user towards the visor.

A method for reducing light leakage in an optical display system configured to display virtual images in a mixed-reality usage scenario in which the virtual images are seen by a user as superimposed over a physical real-world environment, comprising:

• providing a see-through waveguide combiner comprising at least one transparent waveguide having a first surface towards which a user of the waveguide combiner looks to view the real-world environment, and a second surface opposite the first surface, in which an input coupler and an output coupler are disposed on the waveguide;
• configuring the waveguide combiner with a spectral-sensitive reflector on the first surface of the waveguide, the spectral-sensitive reflector reflecting forward-propagating virtual image light that is leaking from the waveguide combiner towards an eye of the user;
• and
• configuring the waveguide combiner with a light deflector disposed along a forward-propagating light path extending from the output coupler of the waveguide combiner towards the real-world environment, wherein the light deflector steers forward-propagating virtual image light that is leaking from the waveguide combiner to impart an angular change in a propagation direction of the virtual image light to change the propagation direction to be away from the eye of the user towards a visor.