TECHNICAL FIELD

Embodiments relate to optical combiner apparatus and components thereof. More particularly but not exclusively, embodiments relate to augmented reality image combiners. Additionally, some embodiments relate to head mounted displays including optical combiners.

BACKGROUND

An optical see through combiner is a fundamental component in an augmented reality display system. The optical combiner enables the real world and an artificially generated scene created by a computer and created by a projector to be optically superimposed.

There are a number of optical systems that have been proposed and adopted with one of the main requirements is to take the projection system away from the eye so it does not obscure the natural view of the world. However, high performance optical combiner systems are complex and difficult to fabricate.

There is a need to provide improved optical combiners that are easier to manufacture and have better performance than current optical systems.

SUMMARY

According to a first aspect, there is provided an optical combiner. The optical combiner may comprise an optically transparent substrate and a patterned region included in the optically transparent substrate and disposed along a wave propagation axis of the substrate. The patterned region may be partially optically reflective and partially optically transparent. The patterned region may comprise a plurality of optically transparent regions of the optically transparent substrate and a plurality of optically reflective regions inclined relative to the optical transparent substrate wave propagation axis.

By including in the optical substrate a patterned region which is partially optically reflective and partially optically transparent, improved optical combiners are provided that are easier to manufacture and have better performance.

According to another aspect, an augmented reality optical combiner is provided. The optical combiner may comprise a transparent optical waveguide substrate for receiving an optical image and viewing there through a distant real world scene and a plurality of reflective elements arranged within the transparent optical waveguide for reflecting the received optical image. The plurality of reflective elements may be arranged in such a way that, when the optical combiner is in use, the received optical image is reflected and superimposed on the real world scene view so as to allow viewing of the distant real world scene while simultaneously viewing the optical image superimposed on the real world scene.

According to yet another aspect, an augmented reality optical apparatus is provided. The augmented reality optical apparatus may comprise a head mounted display and at least one of the aforementioned optical combiners supported on the head mounted display.

According to yet other aspects, methods of combining optical rays are provided. In one aspect, a method of combining optical rays comprises propagating first optical image rays along a length of an optical transparent waveguide substrate towards a pattern region included in said optical transparent substrate; transmitting second optical image rays through a width of the optical waveguide substrate; and selectively reflecting out of said optical substrate said first optical image rays at different points along said substrate from reflective regions of said pattern region; said reflected first optical image rays superimposing on said second optical image rays transmitted out of said optical transparent substrate.

The first optical image rays may be computer generated rays. The second optical image rays may be from a distant real world scene. The pattern region may be a pattern region as set forth hereinbefore.

