All Solid State Laser for DNA Sequencing

Numerous biomedical analysis techniques utilize laser-induced-fluorescence detection. Thisprovides a high sensitivity analysis tool for biomedical research and clinical diagnosis. The mostcommonly used laser for these applications is the Ar-ion laser, since it is well matched to the excitationwavelengths of the most widely used dyes. However this laser is less than optimal for theseapplications: it is fairly large and has low efficiency, so it dissipates much excess heat in the instrumentand consumes substantial electrical power. It also has limited lifetime, so regular repair is necessary.This Phase I aims to investigate the feasibility of developing a compact, efficient, robust, long-lifetimelaser source that would be a superior, cost-effective replacement for Ar-ion lasers in biomedicalinstrumentation. It would be based on new InGaAs diode lasers. The near-infrared output of such adiode would he frequency-doubled in a nonlinear crystal to achieve a wavelength of 510 nm, which isoptimal for DNA sequencing. We will use a resonant doubling cavity to achieve good conversionefficiency. The Phase II follow-on would entail developing a 510 nm source optimized for use in DNAsequencers and other biomedical instruments.