21 Jul 2004
LEDs emitting sub-nanosecond pulses at 280 nm and 340 nm make their commercial debut.
The first commercial ultraviolet LEDs to emit sub-nanosecond pulses at 280 and 340 nm are now available from Jobin Yvon IBH, UK. Forming part of the firm's NanoLED range, the LEDs are said to emit 800 picosecond pulses making them ideal for a range of biological applications based on time-resolved fluorescence.
According to David McLoskey, the company's technical director, the 280 and 340 nm NanoLEDs could replace sources such as gas-based flashlamps, nitrogen lasers and even Ti-sapphire lasers in certain applications.
"One advantage of the [NanoLED] sources is their ease of use and robustness as no servicing or costly support equipment is required, " he explained. "Another advantage is that the sources are really small - only 40 mm in diameter."
McLoskey explained that IBH currently buys continuous-wave versions of the LEDs from an external supplier. "We build in fast switching electronics, additional optics and package everything together," he said. "But the switching electronics is the key to making the LEDs pulsed. We can operate them at repetition rates up to around 1 MHz."
The addition of these two sources extends IBH's NanoLED family from 280 nm to 1.3 microns. McLoskey adds that all of the devices are plug-and-play, interchangeable and generate optical pulses from less than 100 picoseconds to 1 nanosecond. "Once you buy a controller module, you just buy the wavelengths you are interested and swap them," he said.
This flexibility could benefit researchers working in protein research and drug discovery. The 280 nm device matches absorption maxima of the naturally-fluorescent amino acids tryptophan and tyrosine, while the 340 nm device suits experiments using the 337 nm line emitted by nitrogen lasers.