A 405-nm blue diode laser with a repetition rate of 20 to 50 MHz and a pulse width of 75 to 250 ps has been introduced by Boston Electronics Corp. The model BDL-405 is housed in a 160 x 90 x 60-mm package that is shielded from electromagnetic interference. Power levels range from 100 µW to 1 mW, and pulse-to-pulse jitter is <10 ps. Applications include fluorescence lifetime imaging with laser scanning confocal microscopes for measurement of FRET. Additional pulsed diode lasers are available at wavelengths of 635, 650, 660, 670 and 780 nm.