The black fringe wavefront sensor: White light real time analog phase control

White light interferometry techniques to obtain 3D surface profiles or rms surface roughness measurements for microscopic instruments are used to develop an adaptive optics wavefront sensor for long range correction of lasers and images. Combining these techniques with a high power incoherent or multiline laser and a radial shear interferometer, a black fringe wavefront sensor (bfwfs) has been developed over the last two years at Lockheed Martin's Advanced technology Center. The bfwfs will be described, and results of recent tests shown using a 16 channel device. The 16 ch system is used to obtain measurements of open loop influence functions, and closed loop Bode plots using a Mems mirror. The bfwfs device can be used for adaptive optics at long ranges on weight or volume limited platforms because it allows high power incoherent lasers or other broadband sources to be combined with a parallel architecture and inherently analog servo system. Results are reported in which a superluminescent laser diode (SLD) and a multiline cw Argon laser are combined with a radial shear interferometer to measure phase at 200 Hz with 1/20 pv accuracy.