Transparent Waveguide Display

Abstract

One embodiment provides an apparatus for displaying an image comprising: a first optical substrate comprising at least one waveguide layer configured to propagate light in a first direction, wherein the at least one waveguide layer of the first optical substrate comprises at least one grating lamina configured to extract the light from the first substrate along the first direction; and a second optical substrate comprising at least one waveguide layer configured to propagate the light in a second direction, wherein the at least one waveguide layer of the second optical substrate comprises at least one grating lamina configured to extract light from the second substrate along the second direction; wherein the at least one grating lamina of at least one of the first and second optical substrates comprises an SBG in a passive mode.

1 . An apparatus for displaying an image comprising:
 at least one source of image modulated collimated light over an angular range;   at least one waveguide layer comprising gratings for coupling said light into a waveguide path, providing a first direction expansion, a second direction expansion orthogonal to said first expansion and extracting light for viewing from said waveguide, wherein said gratings are configured to provide more than one mode of presentation of data from said source.   
     
     
         2 . The apparatus of  claim 1 , wherein a mode of presentation of data from said source is via one or more exit pupils configured to allow one or more persons to view data from one or more of said sources. 
     
     
         3 . The apparatus of  claim 1 , wherein a mode of presentation of data from said source comprises data displayed at different ranges. 
     
     
         4 . The apparatus of  claim 1 , wherein a mode of presentation of data from said source is via at least one exit pupil configured to view a tiled FOV wherein each FOV tile is formed using one of a plurality of overlaid gratings. 
     
     
         5 . The apparatus of  claim 1 , wherein a mode of presentation of data from said source is via two or more exit pupils configured to view a FOV wherein each exit pupil is formed using one of a plurality of overlaid gratings. 
     
     
         6 . The apparatus of  claim 1 , wherein a mode of presentation of data from said source is via two or more exit pupils each configured to view a different FOV wherein each exit pupil is formed using one of a plurality of overlaid gratings. 
     
     
         7 . The apparatus of  claim 1 , wherein said gratings are selected from a Bragg grating, a SBG, a HPDLC grating, a uniform modulation grating, a reverse mode HPDLC grating and a surface relief grating. 
     
     
         8 . The apparatus of  claim 1 , configured to provide a plurality of waveguide layers, wherein when the plurality of waveguide layers comprises three waveguide layers, the three waveguide layers are configured to propagate red, green, and blue light; and wherein when the plurality of waveguide layers comprises two waveguide layers, the two waveguide layers are configured to propagate red light and mixed blue and green light. 
     
     
         9 . The apparatus of  claim 1 , wherein at least one of said gratings is characterized by at least one of: a grating with rolled k-vectors; a grating multiplexing at least two different grating prescriptions; an overlap with at least one other grating; and a grating with thickness varying across at least one waveguide direction. 
     
     
         10 . The apparatus of  claim 1 , configured as a HUD in which data is presented in different field of view tiles at different ranges. 
     
     
         11 . The apparatus of  claim 1 , configured as a vehicle HUD configured to provide separate exit pupils for a driver and a passenger. 
     
     
         12 . The apparatus of  claim 1 , configured as a vehicle HUD wherein said source is configured to provide images of objects external to said vehicle captured by an imaging sensor. 
     
     
         13 . The apparatus of  claim 1 , configured as a HUD for use in a road vehicle or aircraft. 
     
     
         14 . The apparatus of  claim 1 , configured as a vehicle HUD configured to provide a rear-view mirror comprising a grating overlaying a reflecting layer. 
     
     
         15 . The apparatus of  claim 1 , wherein said source comprises a microdisplay and collimation optics. 
     
     
         16 . The apparatus of  claim 1 , further comprising a source of structured infrared radiation and an infrared detector. 
     
     
         17 . The apparatus of  claim 1 , further comprising a source of structured infrared radiation and an infrared detector configured to perform at least one of the functions selected from the group of: gesture detection, detection of objects in the vicinity of the display and eye tracking. 
     
     
         18 . The apparatus of  claim 1 , wherein said at least one source of image modulated collimated light over an angular range is provided by a two-dimensional array of grating lenslets, wherein each grating lenslet diffracts incident collimated light into a TIR path within the waveguide. 
     
     
         19 . The apparatus of  claim 1 , using a LED source with a peak emission wavelength and further comprising a plurality of gratings with peak diffraction efficiency vs. wavelength characteristics shifted by small increments from said peak emission wavelength diffraction efficiency loss in the spectral bandwidth of LEDs is compensated. 
     
     
         20 . The apparatus of  claim 1 , providing a HUD in which said waveguide is at least one of configuration selected from the group of combined with or integrated within a windscreen; formed as a flexible layer for bonding onto inner or outer surfaces of a windscreen; and curved in at least one plane. 
     
     
         21 . (canceled)