MIT Could Make Inexpensive 3D Holograms A Reality
Researchers at the school's Media Lab are developing a prototype color video display using an optical chip that only cost $10 to build.
Researchers at MIT’s Media Lab have reported a new approach to generating holograms that could lead to the production of inexpensive color holographic-video displays. The same approach also renders much higher resolution 2D displays with lower power consumption.
Daniel Smalley, a graduate student in the Media Lab, is using the approach to build a prototype color holographic-video display with a resolution roughly the same as a standard-definition TV, which can update video images 30 times a second (fast enough to produce the illusion of motion). At the heart of the display is an optical chip, which Smalley built using MIT facilities for around $10.
Smalley creates microscopic channels known as waveguides beneath the surface of a small crystal of “lithium niobate,” which confines the light traveling through them. Onto each waveguide he deposits a metal electrode, which can produce an acoustic wave.
Each waveguide corresponds to one row of pixels in the final image and they can be packed micrometers apart from each other. Beams of red, green and blue light are sent down each waveguide, and the frequencies of the acoustic wave passing through the crystal determine which colors pass through and which are filtered out.