Displays with integrated backlighting

A method, comprising:

• coupling light of at least first and second different colors to a waveguide of a first substrate;
• diffractively out-coupling light of at least said first color through a first optical layer of the first substrate to pre-selected pixels or subpixels of said pixels;
• diffractively out-coupling light of at least said second color through a second optical layer of the first substrate to pre-selected pixels or subpixels of said pixels wherein the second optical layer is stacked on the first optical layer,
• wherein said pre-selected pixels or subpixels of said pixels comprising conductive electrodes and located on the first or a second substrate;
• modulating said light of different colors in predetermined areas of a modulation layer corresponding to said pixels by applying electric signals corresponding to data of an image to said pixels for providing electric fields between said pixels in the first or second substrate and an electrically conducting layer of an opposite, second or first substrate,
• wherein said modulation layer is between the first and second substrates;
• and further out-coupling said light of different colors out of said second substrate after said light being modulated by said electric fields corresponding to said data of said image for providing said image.

An apparatus, comprising:

• first means for light propagation;
• second means for light propagation;
• and
• means for modulation between said first and second means for light propagation,
• wherein light modulation in predetermined areas of said means for modulation corresponding to pixels comprising conductive electrodes and located on the first or the . second means for light propagation is provided by applying electric signals corresponding to data of an image to said pixels for providing electric fields between said pixels and an electrically conducting layer of an opposite second or first means for light propagation,
• wherein said first means for light propagation comprises a waveguide configured to provide launching of light of different colors and comprising
• a first optical layers configured to provide diffractive out- coupling of light of at least a first colors to preselected pixels or subpixels of said pixels,
• a second optical layer, stacked on the first optical layer. configured to provide diffractive out-coupling of light of at least a second color,
• wherein said second means for light propagation is configured to provide further out-coupling of said light of different colors after said light being modulated by said electric fields corresponding to said data of said image for providing said image.

An apparatus, comprising:

• a first substrate;
• a second substrate:
• and
• a modulation layer between said first and second substrates. wherein light modulation in predetermined areas of said modulation layer corresponding to pixels comprising conductive electrodes and located on the first or the second substrate is provided by applying electric signals corresponding to data of an image to said pixels for providing electric fields between said conductive electrodes of the first or the second substrate and an electrically conducting layer of an opposite, the second or the first substrate,
• wherein said first substrate is configured to receive and guide light of different colors and comprises a plurality of diffraction gratings having
• a first diffraction grating configured to provide diffractive out-coupling of light of at least a first color to pre-selected pixels or subpixels of said pixels, and
• a second diffraction grating configured to provide diffractive out-coupling of light of at least a second color to pre-selected pixels or subpixels of said pixels, wherein a groove direction of the second diffraction grating is substantially orthogonal to a groove direction of the first diffraction grating, and
• wherein said second substrate is configured to provide further out-coupling of said light of different colors after said light being modulated by said electric fields in said modulation layer corresponding to said data of said image for providing said image.

A method, comprising:

• coupling light of different colors to a first substrate, wherein the first substrate is configured to receive and guide light of different colors and comprises a first diffraction grating and a second diffraction grating;
• using the first diffraction grating to diffractively out-couple light of at least a first color to pre-selected pixels or subpixels of said pixels;
• using the second diffraction grating to diffractively out-couple light of at least a second color to pre-selected pixels or subpixels of said pixels, wherein a groove direction of the second diffraction grating is substantially orthogonal to a groove direction of the first diffraction grating, and wherein said pixels comprising conductive electrodes and located on the first or a second substrate;
• modulating portions of each of said light of different colors in predetermined areas of a modulation layer corresponding to said pixels by applying electric signals corresponding to data of an image to said pixels for providing electric fields between said conductive electrodes located on the first or the second substrate and an electrically conducting layer of an opposite, the second or the first substrate, wherein said modulation layer is between the first and second substrates;
• and
• further out-coupling said portions of each of said light of different colors out of said second substrate after being modulated by said electric fields corresponding to said data of said image for providing said image.