Air Force Shoots the Moon With New Digital Cameras
Breakthroughs by Air Force scientists looking for better ways to see what happens when weapons smash into their targets are creating an explosion of spinoffs.
Their work with high-speed digital and holographic photography is expected to help doctors diagnose patients, give movies even more incredible special effects, make flying safer and even help baseball players hit and pitch better.
“We ignited a fire in industry, and now it’s gone beyond what we had hoped,” said team leader Don Snyder, a senior scientist at the Air Force Research Laboratory on this Florida Panhandle base.
Officials project a marketplace impact in excess of $1 billion annually from companies that have developed new products and grown as a result of their involvement in the Air Force’s $20-million project.
Snyder’s eight-member Experimental Dynamics Imaging Team also has won a half-dozen scientific and military awards and is eyeing a possible Oscar nomination if final tests of the world’s first true holographic movie camera pan out.
The team’s success in replacing film with digital images in high-speed photography has been “revolutionary, rather than just evolutionary,” said Alan M. Frank, a physicist at the Lawrence Livermore Laboratory in California.
Frank chairs a subcommittee of the International Society for Optical Engineering that chose the Eglin team for the organization’s 1998 Harold E. Edgerton Award. It is named for a Massachusetts Institute of Technology researcher who pioneered high-speed photography in the 1930s.
The Eglin team was created in the late 1980s because researchers were having trouble determining exactly what happens when a bullet, bomb or other weapon strikes home. Smoke and fire from explosions and the flash of metal hitting metal can blind even the best high-speed cameras.
“When everything gets to the point where it’s really interesting, you can’t see,” Snyder said. “Our challenge was to find new ways to see what was going on.”
The scientists also wanted to do it in real time--impossible when developing film takes hours--and replace cameras weighing half a ton and costing $500,000 with something smaller, cheaper and simpler.
Working with university and industry researchers, the team developed silicon chips that act like high-speed shutters, and the world’s fastest recording device--15 gigabits per second of solid-state computer memory.
“It’s like 20 to 30 VCRs stacked up, but we’re doing it in a shoe box,” Snyder said.
One camera shoots 1,000 frames per second, and Snyder hopes the cost will drop low enough--about $15,000--for use in high school science classes. Another version gets 1 million frames per second and costs $50,000. Working in pairs, they produce 3-D pictures on computer screens.
By comparison, the standard television camera produces 30 images per second.
To filter out smoke and flash, the scientists turned to lasers and developed a plasma light similar to the kind used for some laptop computer screens except much brighter and pulsing a million times or more per second.
These sources of “light in flight” outshine an explosion, said Maj. Ken Echternacht, deputy ordnance chief at the lab.
The plasma flasher has potential outside high-speed photography for anti-collision lights on aircraft and communications towers, Snyder said. An ultraviolet version could kill fungus on fruit.
The digital cameras and lasers with pulses as short as a few billionths of a second can work as an “optical radar” to see inside the human body with better resolution than X-rays and without any radiation hazard, Snyder said.
Although not yet approved in the United States, digital imaging based on the team’s work is used in some countries to scan thousands of medical laboratory slides in a second, searching for signs of cancer, Snyder said. That compares with 80 to 100 a pathologist can scan manually in a day.
An obvious spinoff is movie special effects, but Snyder said scientists in Japan are interested in the technology partly because of another entertainment popular in their country--baseball. The cameras’ super slow-motion pictures of ballplayers can be helpful in improving their performance.
Auto industry uses include crash testing and air-bag and fuel-injection research. Navy scientists are applying the technology in a device to warn pilots of impending failure by analyzing oil in jet engines.
The National Solar Observatory used one of the sensors in a special camera to forecast sunspots, which can knock out aircraft and satellite communications, days ahead of time instead of just hours, Snyder said.
NASA is using the cameras in testing armor to protect satellites against micro-meteorites.
In addition to munitions testing, the Air Force may apply the technology to weapons guidance systems, Snyder said.
One of the team’s goals was to cut costs by letting industry use the research to produce hardware so the Air Force could buy it off the shelf. That mission has been accomplished, Snyder said. Delivery is expected in the coming months.
“We knew that we would stimulate competition,” Snyder said. “We just didn’t know how vicious it would get, which is great. This is exactly what we wanted.”
