Adaptive optics
Absolutely essential (light bucket syndrome...)
“Better suited” to large telescopes:
- total resolution points in compensated field ~ D2
Multistage compensation concept
Phase excursion 30µ PV (for outer scale of 50m)
- ‘almost’ feasible right now (piezostack, MEMS)
Requirements (for Sr = 50% at V):
- 2 105 actuators, 100 Hz bandwidth, ~ 10 laser GSs
- Rates of 2 G pix/s (detectors almost there, computers need 300x)
Turbulence tomography most attractive solution
- few (if any!) LGSs (for D ~ 100m sufficient natural GSs)