Precision Actuator Positions Laser Grating

The tunable external cavity diode laser is an important new tool used to evaluate and test the latest fiber-optic components and building blocks of modern telecommunications systems. A key factor enabling operation of this type of laser is the ability to angle-tune the wavelength-dependent key component (a diffraction grating) in the cavity with extreme precision and repeatability. When Hewlett Packard wanted to develop a laser with enhanced wavelength performance, their design required a linear actuator with 100-nm resolution over a travel range of several millimeters. This brief tells how a custom microstepper system was developed to meet the needs of this demanding application.