Real-Time Computing (RTC) is an important challenge in Adaptive Optics (AO) in order to compensate for high-velocity perturbations. The ultimate performance is often a trade-off between expensive and complex clusters and versatility. ALPAO has developed the ALPAO RTC solution, which runs on a standard server, making it highly adaptable to various AO system configurations.

It can run on a common server machine or a common cluster. Originally, ALPAO RTC was designed to control AO loops involving Shack-Hartmann Wave Front Sensors. ALPAO RTC is also part of SISO (Single Input Single Output) and MIMO (Multiple Input Multiple Output) systems that achieve, for instance, a frame rate of 3kHz and an RTC latency delay (the duration between total retrieval of the image and command sent) of less than 70µs on a 256x256 pixels, 32x32 micro-lens SHWFS, and an 820-actuator Deformable Mirror. ALPAO RTC is also running in a Laser Guide Star system, controlling downlink and uplink.

Finally, ALPAO RTC is now part of a system involving a Pyramid Wave Front Sensor currently operating on a telescope.

Bruno Martin, ALPAO