Reconfigurable Shack-Hartmann wavefront sensor

Jungtae Rha; David G. Voelz; Michael K. Giles

doi:10.1117/1.1625950

1 January 2004 Reconfigurable Shack-Hartmann wavefront sensor

Jungtae Rha, David G. Voelz, Michael K. Giles

Optical Engineering, Vol. 43, Issue 1, (January 2004). https://doi.org/10.1117/1.1625950

The conventional Shack-Hartmann wavefront sensor (SH-WFS) has a fixed subaperture area that is determined by consideration of several parameters such as the average atmospheric coherence diameter r₀ at the telescope site. Its SNR can be severely degraded due to low-light conditions caused by increasing turbulence, strong atmospheric scintillation, or simply viewing a faint object. Typically, the integration time of the sensor is increased to improve the SNR. Unfortunately, a decrease in bandwidth causes an increase in residual wavefront error that reduces image quality. We show that an increase in subaperture area produces a smaller residual wavefront error than an equivalent increase in integration time. Furthermore, we show that the ability to reconfigure the subaperture area, in combination with control bandwidth adjustment, provides superior performance over a system with fixed subaperture area when r₀ is different than the design point. We present a reconfigurable Shack-Hartmann wavefront sensor (RSH-WFS) with adjustable subaperture area implemented using a phase-modulated liquid crystal device (LCD). Experimental results demonstrate that the RSH-WFS increases system dynamic range by increasing the subaperture diameter whenever the Hartmann spot irradiance falls below the threshold of operation of the conventional SH-WFS.

©(2004) Society of Photo-Optical Instrumentation Engineers (SPIE)

Citation Download Citation

Jungtae Rha, David G. Voelz, and Michael K. Giles "Reconfigurable Shack-Hartmann wavefront sensor," Optical Engineering 43(1), (1 January 2004). https://doi.org/10.1117/1.1625950

Published: 1 January 2004

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available