Holographic display and methods of manufacture and use

A holographic display, comprising:

• at least three holographic projection units configured and arranged to create images that overlap with each other to form a final multicolor image, each image creation unit comprising
• a write beam generator,
• a read beam generator, and
• a rewriteable diffraction grating configured and arranged to generate a diffraction pattern in response to a write beam from the write beam generator and to produce an image when illuminated with a read beam from the read beam generator, the rewriteable diffraction grating comprising
• a first layer;
• a second layer adjacent to the first layer, the first and second layers defining a boundary between the first and second layers;
• a plurality of first nanoparticles, wherein each first nanoparticle is configured and arranged to selectively generate one or more charge carriers in response to the write beam;
• and
• a plurality of second nanoparticles, wherein the second nanoparticles are different in composition from the first nanoparticles and each second nanoparticle is configured and arranged to substantially alter its opacity to light from the read beam upon receiving one or more charge carriers from the first nanoparticles and thereby form a light diffraction pattern, with regions that are substantially transparent to the read beam and regions that are substantially opaque to the read beam, in response to the diffraction pattern written on the plurality of first nanoparticles by the write beam;
• wherein the plurality of second nanoparticles are disposed in proximity to the plurality of first nanoparticles to permit charge carriers generated by the first nanoparticles to be transferred to the second nanoparticles and to selectively interact with the second nanoparticles;
• and
• wherein the second nanoparticles are configured and arranged for erasing the light diffraction pattern by releasing one or more charge carriers in response to illumination of the second nanoparticles with an erase beam;
• wherein the first nanoparticles are primarily disposed in the first layer and the second nanoparticles are primarily disposed in the second layer, wherein a portion of the first nanoparticles are diffused into the second layer across the boundary between the first and second layers and a portion of the second nanoparticles are diffused into the first layer across the boundary between the first and second layers.

A method of making a holographic image, the method comprising:

• writing a diffraction pattern on each of a plurality of rewriteable diffraction gratings using a write beam, wherein each of the rewriteable diffraction gratings comprises
• a first layer;
• a second layer adjacent to the first layer, the first and second layers defining a boundary between the first and second layers;
• a plurality of first nanoparticles, wherein each first nanoparticle is configured and arranged to selectively generate one or more charge carriers in response to a write beam;
• and
• a plurality of second nanoparticles, wherein the second nanoparticles are different in composition from the first nanoparticles and each second nanoparticle is configured and arranged to substantially alter its opacity to light from a read beam upon receiving one or more charge carriers from the first nanoparticles and thereby form a light diffraction pattern, with regions that are substantially transparent to the read beam and regions that are substantially opaque to the read beam, in response to a diffraction pattern written on the plurality of first nanoparticles by the write beam;
• wherein the plurality of second nanoparticles are disposed in proximity to the plurality of first nanoparticles to permit charge carriers generated by the first nanoparticles to be transferred to the second nanoparticles and to selectively interact with the second nanoparticles;
• and
• wherein the second nanoparticles are configured and arranged for erasing the light diffraction pattern by releasing one or more charge carriers in response to illumination of the second nanoparticles with an erase beam;
• wherein the first nanoparticles are primarily disposed in the first layer and the second nanoparticles are primarily disposed in the second layer, wherein a portion of the first nanoparticles are diffused into the second layer across the boundary between the first and second layers and a portion of the second nanoparticles are diffused into the first layer across the boundary between the first and second layers;
• illuminating each of the diffraction patterns with a corresponding read beam;
• and
• overlapping the images formed by each of the diffraction patterns.

A method of making a rewriteable diffraction grating, the method comprising:

• forming a first layer comprising a plurality of first nanoparticles, wherein each first nanoparticle is configured and arranged to selectively generate one or more charge carriers in response to the write beam;
• forming a second layer comprising a plurality of second nanoparticles, wherein the second nanoparticles are different in composition from the first nanoparticles and each second nanoparticle is configured and arranged to substantially alter its opacity to light from a read beam upon receiving one or more charge carriers from the first nanoparticles and thereby form a light diffraction pattern, with regions that are substantially transparent to the read beam and regions that are substantially opaque to the read beam, in response to a diffraction pattern written on the plurality of first nanoparticles by the write beam, wherein the plurality of second nanoparticles are disposed in proximity to the plurality of first nanoparticles to permit charge carriers generated by the first nanoparticles to be transferred to the second nanoparticles and to selectively interact with the second nanoparticles, and wherein the second nanoparticles are configured and arranged for erasing the light diffraction pattern by releasing one or more charge carriers in response to illumination of the second nanoparticles with an erase beam;
• and
• diffusing a portion of the first nanoparticles into the second layer across the boundary between the first and second layers and diffusing a portion of the second nanoparticles into the first layer across the boundary between the first and second layers.