Optoelectronics
Pulsed Laser Diodes with integrated FAC Optics
1550 nm pulsed laser diodes (PLDs) are integrated into rangefinder systems, etc. Standard night-vision goggles cannot detect this wavelength. Thus, these PLDs are particularly useful in military laser rangefinders or in friend/foe recognition.
HighThe Divergence of the fast axis was optimized by the additional assembly of a fast axis collimation (FAC) lens that is attached directly in front of the laser diode chip. Depending on the lens used, divergences of 10 mrad can be achieved. The integration of both the chip and the lens in a small, hermetically sealed TO-46 housing is particularly advantageous. This design withstands acceleration rates of over 1000 g/ms without a problem, as is required for use in military technology.
This technology is also optionally available with 905 nm pulsed laser diodes. If the wavelength has to be controlled exactly, a thermoelectric cooler (TEC) can be integrated into a TO-8 housing.
The base material of the 1550 series is InP with additional InGaAsP layers. The InGaAsP structure ensures high reliability, very good beam characteristics, and a high temperature stability. The wide operating temperature range is between –45°C and +85°C. The 1550 nm pulsed laser diodes are housed in a TO-18 can. They are also available in 9 mm packages or in customer-specific designs.