Wavefront sensing based on the inverted Hartmann sensor

The classic Hartmann test consists of an array of holes to reconstruct the wavefront from the local deviation of each focal spot, and Shack-Hartmann sensor improved that with an array of microlenses. This array of microlenses imposes practical limitations when the wavefront is not into of visible wavelengths, e.g., the fabrication of these. Instead, we propose a wavefront-sensing technique using an array of circular obstructions, i.e., the Hartmann sensor with an inverted Hartmann array. We show that under the same conditions the inverted Hartmann sensor and the Shack-Hartmann wavefront sensor have an equivalent spot-map to recover the wavefront. The method might used in non-visible wavelengths and in a wider range of applications.