Vuzix Corporation
IMAGING LIGHT GUIDE WITH EXPANDED LIGHT DISTRIBUTION

Abstract:

An imaging light guide for conveying a virtual image has a waveguide that conveys image-bearing light, formed as a flat plate having a front and a back surface and having an in-coupling diffractive optic on the front surface with a first grating vector diffracting an image-bearing light beam into the waveguide and directing diffracted light. An out-coupling diffractive optic is formed on the front or back surface as a diffractive array and with a first subset of diffractive elements, each having a second grating vector k2 offset from the first grating vector by about +60 degrees and a second subset of diffractive elements, each having a third grating vector k3 offset from the first grating vector by about -60 degrees. Each diffractive element of the first subset is immediately adjacent to at least one diffractive element of the second subset and the diffractive elements are mutually non-overlapping.