A line of UV GaAs photodiodes with spectral sensitivity spanning 150 to 570 nm is available. Optionally, spectral sensitivity is limited to 245 to 400 nm if integrated UV-filter glass windows are employed. Unlike silicon photodiodes, GaAs devices are said to have better signal-to-noise ratio, better temperature stability, and optimized rejection of visible wavelengths.
The photodiodes can be used without the need for high-pass filters. Switching times are minimized by Schottky contacts with a very low capacity. Hermetically-sealed TO-46 and TO-39 packages are available. Optionally, the devices can be fitted with a sapphire window or a UV-filter glass window. A number of active sensor areas are available, including, 0.5, 1.2, 4.8, and 10.9 mm2.
The UV photodiodes start at $10.20 each in 1000-unit quantities.
Roithner Lasertechnik
www.roithner-laser.com; +43 1 586 52 43-0.