Healing wounds with lasers, vehicles that drive themselves, other cutting-edge optics

WORLD'S HIGHEST-RESOLUTION PROJECTOR

If one were to stack 16 of the world's best high-definition projectors side-by-side (and on top of each other), the combined image projected would contain 33 megapixels. This is the resolution achieved by the world's highest-resolution projector, soon to be unveiled by the company Evans & Sutherland (E&S) of Salt Lake City, Utah.

Most projectors contain two-dimensional arrays of pixels, tic-tac-toe arrangements of tiny microelectromechanical systems (MEMS) devices that each light up with a particular color. Because fabricating 33 million of these devices is a tricky endeavor, the E&S projector only uses a single column of 4,000 pixels, powered by a beam of laser light. This rapidly-changing vertical stripe of colors is swept across a screen faster than the eye can see, so spectators see the illusion of a projected 2-D image.

To create this projector, twice the resolution of any that currently exists, the company had to develop powerful fiber lasers. These lasers, discussed in Forrest Williams' talk, may have uses for other projects, such as making anti-counterfeit identifiers or projecting artificial stars into the night sky that can be used to calibrate astronomical instruments.

The projector, which creates a 2:1 image twice as wide as it is high, will be marketed to planetariums, simulations, and training companies that currently wire multiple projectors together to display large images.

Presentation PThA2; Thursday, June 4, 11 – 11:30 a.m.

PICOSECOND OSCILLOSCOPE

An oscilloscope is a device for displaying signals that are too fast to be seen by the human eye. Typically the signal consists of a voltage level that changes quickly moment by moment (over millisecond to nanosecond timescales). What is seen on the screen of the scope is a waveform whose value is graphed along the vertical axis as a function of the horizontal axis representing time. An electron beam, aimed at a phosphorescent screen, is swept horizontally providing a light-trace on the screen while, coincidentally, the instantaneous voltage of the input signal is used to deflect the electron beam up or down, creating the visible trace. The dynamic range of this whole process is the range of voltage values that can be displayed; the other important feature is the time resolution: how fine a time scale can be achieved. Conventional analog television displays use comparable technology. A trace is swept horizontally across the screen, but instead of deflecting the beam up and down, the beam is interrupted or allowed to proceed toward the phosphor screen, where the trace shows up as a bright or dark spot. The display is then scanned across the screen again in a raster pattern to build up a complete screen image (but so quickly that the human eye doesn't notice it at a rate of 30 or 60 frames per second).