Massachusetts Institute of Technology

Other

Brigham Young University

Light Field Lab, Inc.

Daniel E Smalley

V Michael Bove, Jr

Quinn Y J Smithwick

Sundeep Jolly

Victor Michael Bove, Jr

Quinn Smithwick

Kenny Squire

Nickolaos Savidis

Bianca Datta

A holographic display is comprised of space-multiplexed elemental modulators, each of which consists of a surface acoustic wave transducer atop an anisotropic waveguide. Each 'line' of the overall display consists of a single anisotropic waveguide across the display's length with multiple surface acoustic wave transducers spaced along the waveguide length, although for larger displays, the waveguide may be divided into segments, each provided with separate illumination. Light that is undiffracted by a specific transducer is available for diffraction by subsequent transducers. Per transducer, guided-mode light is mode-converted to leaky-mode light, which propagates into the substrate away from the viewer before encountering a volume reflection grating and being reflected and steered towards the viewer. The display is transparent and all reflection volume gratings operate in the Bragg regime, thereby creating no dispersion of ambient light.

Near-to-eye and see-through holographic displays

A method and system are disclosed for using circular symmetry to eliminate the angle limitations of an optical axis in a scanned aperture holography system. A Room-sized Holography System may be a scanned aperture holographic video display and may comprise a rotating platform, a telescope comprising a first lens and a second lens, and scanners at the Fourier plane where the focal length of the first lens and the second lens meet. The platform may rotate around an axis aligned with a spatial light modulator. When the platform rotates, the scanners rotate, thereby de-rotating a SAW image. The second lens may be a spherical reflective surface for redirecting light from the spatial light modulator, having passed through the first lens and reflected off a mirror-scanner, toward a user's eyes. The user may be on a chair above the spatial light modulator, wherein the chair is configured to rotate with the spatial light modulator.

Room-sized holographic video

A method and system for a scalable multi-sense user experience are disclosed. A three-dimensional ('3-D') display is disposed behind a slit plane comprising slits and ultrasonic transducers. Light from the 3-D display passes through the slits in the slit plane to generate a 3-D image. The ultrasonic transducers on the front of the slit plane, i.e., opposite the side where the 3-D display is disposed, generate directed acoustic field and/or a formed tactile field. Because the generating components for all three senses, i.e., visual, audio, and tactile, are coplanar, units may be tiled and thereby scaled to generate larger multi-sense experiences.

Tileable, coplanar, flat-panel 3-D display with tactile and audio interfaces

In a method for forming a holographic image, light is provided to a flat-panel holographic video display that includes waveguide elements that each have a light-guiding substrate and an array of transducers configured to produce a diffraction grating comprising surface acoustic waves. The grating causes the waveguide to outcouple light, focusing it to, or producing wavefront curvatures consistent with it having emanated from, one or more points, in order to form a holographic image. The transducer array may include a large number of densely packed, vertically-adjacent transducers for each hogel for full parallax or may include a small number of vertically-adjacent transducers and a cylindrical optical element for each hogel. The display may be edge-illuminated by a collinear multicolor source. The substrate exit face may have nanopatterned areas alternated with flat areas in order to create regions of optimal internal reflection next to regions of low reflection.

Transparent flat-panel holographic display

A system for three-dimensional (3D) optical trap printing (OTP) comprises a first particle susceptible to being cured by a light beam, a first light source to generate a trapping light beam to trap the particle, and a second light source to generate a curing light beam to cure the first particle. Using scanning and other optics, the trapping light beam may move the first particle to a desired printing location at which the curing light beam may cure the first particle, thereby adding the first particle to a printed structure. Using OTP, structures may be printed in any orientation, with or without support structures. Additionally, OTP allows for printing composite materials, high resolution color printing, printing of complex structures without sacrificial filler material, simultaneous printing of multiple particles, and combining particles at a print location.

Optical trap 3D printing

A method and system for using laser-induced structures to direct light to exit the bottom of a leaky mode device, and further to divide leaky mode light into multiple orders, and to implement one or more pulsing/strobing patterns such that a field of view is increased for a viewer, or the view zone is increased for a viewer. A leaky mode device may comprise a substrate, a surface acoustic wave ('SAW') transducer, a waveguide having a higher refractive index than the substrate, an input region for input light, and laser induced structures such as grating. The SAW transducer may be positioned on a top surface of the substrate, and may be configured to emit a SAW wave to propagate across the substrate. The waveguide may be positioned below the SAW. The input wave region may be configured to couple light onto the waveguide. When light is coupled onto the waveguide, the refractive index may change such that the light in the waveguide exits the waveguide as leaky mode light and interacts with the laser-induced grating, which is below the waveguide. The laser-induced grating is configured to divide the leaky mode light into multiple orders, each bent at a different angle.

Structures for modifying leaky mode light

A method and system for recycling signals in a leaky mode device for a holographic display or other application. A leaky mode device comprises at least a first transducer, a substrate, and a second transducer. The first transducer may be configured to receive an input signal from a signal arbiter, which forwards to the first transducer as an input signal either a new input signal or a recycled input signal (or some combination of the two). The first transducer converts the received input signal to a SAW (surface acoustic wave) and transmits the SAW through the substrate to the second transducer, which converts the received SAW to an output signal, and forwards the output signal to an amplifier, which amplifies the output signal (now a 'recycled' signal) and forwards to the signal arbiter. This system facilitates persistence for points in a holographic display without the need for continually rewriting to leaky mode devices.

Circular buffers for leaky mode displays

A flat-panel holographic video display includes a control layer and waveguide elements. Each waveguide element has a light-guiding substrate and an array of transducers configured to produce a diffraction grating comprising surface acoustic waves. The grating causes the waveguide to outcouple light, focusing it to, or producing wavefront curvatures consistent with it having emanated from, one or more points, in order to form a holographic image. The transducer array may include a large number of densely packed, vertically-adjacent transducers for each hogel for full parallax or may include a small number of vertically-adjacent transducers and a cylindrical optical element for each hogel. A spatial filter may be used to block noise. The display may be edge-illuminated by a collinear multicolor source. The substrate exit face may have nanopatterned areas alternated with flat areas in order to create regions of optimal internal reflection next to regions of low reflection.

A system includes a particle configured for emitting light in response to stimulation by a light beam, a first light source configured for generating a first light beam that traps the particle in a potential well created by the light beam in air, and a second light source configured for generating a second light beam that stimulates the particle to emit emission light.

Full-color freespace volumetric display with occlusion

An anisotropic spatial acousto-optic modulator for a holographic display system includes a substrate, an anisotropic waveguide that guides light into a single polarization, and a transducer that generates surface acoustic waves that propagate linearly with the guided, polarized light, converting at least some of the polarized light into a leaky mode of orthogonally polarized light. The acoustic waves may be encoded with holographic information. The modulator may include coupling devices for coupling light into the waveguide, which may have multiple channels. A holographic video display system includes at least one anisotropic spatial acousto-optic modulator. The pattern of the surface acoustic waves, encoded with holographic information, acts as a diffraction pattern that causes the modulator output to form a wavefront that becomes at least part of a holographic image. The system may have multiple channels in multiple waveguides, wherein each waveguide writes one or more lines of the holographic image.

Anisotropic leaky-mode modulator for holographic video displays

A holographic video display employs at least one light source adapted to produce at least one wavelength of monochromatic light, a video signal generator, at least one guided-wave acousto-optic modulator for diffracting light received from the light source according to signals received from the video signal generator, a vertical scanning subsystem, and an optical path between the acousto-optic modulator and the vertical scanning subsystem. The optical path may preferably include a Bravais lens system, at least one Fourier transform lens system, and at least one moving horizontal mirror.

Holographic video display system

In an illustrative implementation of this invention, an animated holographic display is created as follows: Multiple HPO holograms in the shape of horizontal strips are recorded on an H2 medium. These horizontal strips are vertically displaced from each other. An animated real image is displayed by sequentially illuminating these HPO holograms. In illustrative implementations of this invention, the vertical perspective of at least some adjacent HPO stripes are identical.

Methods and apparatus for holographic animation

A holographic video display comprises a monochromatic light source, a video signal generator, guided-wave acousto-optic modulators for diffracting light according to signals received from the video signal generator, a vertical scanning subsystem, and an optical path between the acousto-optic modulator and the vertical scanning subsystem. The optical path preferably comprises a Bravais lens system, first and second Fourier transform lens systems, and at least one holographic optical element or stationary mirror of continuous helical shape. In a method for generating a holographic image, monochromatic light is provided to at least one guided-wave acousto-optic modulator, the received light is diffracted according to a video signal, the guided-wave modulator aperture is scanned to produce a holo-line, the motion of the diffraction pattern is undone to render the holo-line stationary, the guided-wave modulator aperture is demagnified to create a wide field of view, and the holo-lines are tiled vertically to create the image.

Growing community of inventors

Cambridge, MA, United States of America

Daniel E Smalley