STEAM camera technology

In conventional digital imaging such as CCD and CMOS cameras, the rate at which images are produced is restricted by the time it takes to read data from an array of millions of sensors. Also, as you increase the shutter speed, you are reducing the amount of light that reaches the sensors resulting in images of limited quality. "To put it simply, when you are taking a picture, you can't collect enough light from an object if the exposure time is short," Goda told physicsworld.com.

To get around this compromise, the UCLA researchers have developed a new technology which they refer to as STEAM - "Serial Time-Encoded Amplified Microscopy". STEAM works by freezing images using an optical rather than an electronic process. At its heart, a single-pixel photodiode and oscilloscope capture a stream of one dimensional time-varying data then convert this into high-quality two dimensional images.

Presenting their findings in Nature, the scientists used their camera to record laser ablation - a technique used in surgery to remove targeted areas without damaging near-by tissue. The ablation was performed with a mid-infrared pulse laser focused on a silicon substrate coated with aluminium foil. The camera, normally incident to the substrate surface, was able to capture the particle ejection at a frame rate of 6.1 MHz, where high-end digital cameras can manage only 1kHz.

Source: physicsworld.comAdded: 29 May 2009