Partial atmospheric correction with adaptive optics

Adaptive optics has seen only limited application in astronomical facilities, despite its significant potential for improving seeing conditions and increasing observing efficiency and productivity. Expense and technological difficulty appear to be the reasons that this is the case. Correction of large apertures requires hundreds of active elements in both the wave-front sensor and the adaptive mirror. We have performed some one-dimensional numerical simulations to test atmospheric wave-front correction when the active element is not matched to the correlation scale in the pupil. The results demonstrate that substantial seeing improvement can be obtained with an adaptive optical system having a limited number of active elements.