June 27, 2006, Rodgau, Germany--Omicron has introduced a diode laser that has what the company says is almost infinite modulation capability. The laser, called the Deepstar, does not show any residual fluorescence content in the "off" moments while being modulated, even at very high modulation rates. The temperature-stabilized diode laser can be modulated at greater than 100 MHz.
The analog or digitally modulated laser-diode module has a modulation depth of significantly higher than 100,000:1 (the maximum depth was not specified). The lasers are suitable for fluorescence excitation and other applications in which no remaining light is allowed in "off" periods during modulation--for example, confocal-laser-scanning microscopy and flow cytometry. Ultradeep analog modulation can be accomplished at greater than 10 MHz and digital modulation at greater than 100 Mhz, with a signal rise and signal fall time of less than 2 ns. The laser is also suitable for other high-performance applications that were previously possible only with combinations of continuous-wave lasers and acousto-optic modulators.
Versions of the Deepstar diode laser include devices that emit 20 mW at 375 nm, 60 mW at 405 nm, 50 mW at 442 nm, and 20 mW at 473 nm, as well as powers up to 150 mW at 635 to 980 nm. The laser has a controller equipped with an RS-232 interface and is operated at a voltage of 24 V DC. Analog and digital signal inputs can be configured with respect to voltage and impedance so that adaptation to the existing signal sources can be implemented easily. The modular form of the laser allow for configurations that include single-mode fiber coupling (with an efficiency of up to 75%), collimation with a beam diameter of 0.5 to 15 mm, and so on.
The laser was introduced at Optatec (June 20-23, 2006; Frankfurt, Germany).