SUBSTRATE-GUIDED OPTICAL DEVICE
There is provided an optical device, including a light waves-transmitting substrate having two major surfaces and edges, optical means for coupling light into the means for coupling light into the substrate by total internal reflection, and plurality of partially reflecting surfaces ( 22 a , 22 b ) carried by the substrate wherein the partially reflecting surfaces ( 22 a , 22 b ) are parallel to each other and are not parallel to any of the edges of the substrate, and wherein one or more of the partially reflecting surfaces ( 22 a , 22 b ) is an anisotropic surface.
1 . An optical device, comprising:
a light waves-transmitting substrate having at least two major surfaces and edges;
a display source;
optical means for coupling light waves from the display source into the substrate by total internal reflection, and
a plurality of partially reflecting surfaces carried by the substrate wherein the partially reflecting surfaces are parallel to each other and are not parallel to any of the edges of the substrate;
characterized in that the optical device allows dual operational modes in see-through configuration, wherein in a first mode, image light waves are projected from the display source through the substrate into an eye of a viewer, and in a second mode, the display source is shut-off and an external scene is viewable through the substrate.
2 . The optical device according to claim 1 , wherein in one of the dual operational modes the device is utilized as a conventional spectacle lens.
3 . The optical device according to claim 1 , including a second display source wherein an image from an external scene transmitted through the substrate, emerges from the second display source.
4 . An optical device, comprising:
a light waves-transmitting substrate having at least two major surfaces and edges;
a display source;
optical means for coupling light waves from the display source into the substrate by total internal reflection,
a plurality of partially reflecting surfaces carried by the substrate wherein the partially reflecting surfaces are parallel to each other and are not parallel to any of the edges of the substrate, and
wherein the plurality of partially reflecting surfaces defines an active area and an inactive area of the substrate, an image from the display source is projected through the active area of the substrate into at least one eye of a viewer and an external scene is transmitted through an inactive area of the substrate to at least one eye of a viewer.
5 . The optical device according to claim 4 , wherein an opaque layer is located in front of the active area of the substrate and the inactive area of the substrate is transparent.
6 . The optical device according to claim 4 , wherein a variable filter placed in front of the substrate, enables a viewer to control the level of brightness of the light waves emerging from the external scene.