Wavefront sensing by means of binary intensity modulation

Abstract

We propose a kind of wavefront sensing technique by means of binary intensity modulation. A digital micromirror device operates as a binary intensity modulator and a pinhole works as a binary-aberration-mode filter. Through modulating intensity distribution of incident light, light emitting from the pinhole is capable of containing information on binary aberration coefficients. With the amount of light acquired by a single detector, the coefficients of binary aberration modes for reconstructing incident wavefront can be calculated. Differing from the conventional wavefront sensing technique, this method turns the complex two-dimensional wavefront sensing into simple total-light-intensity detection. The simulation experiment has validated the feasibility of the theoretical model.

Wavefront reconstruction algorithm for wavefront sensing based on binary aberration modes

“…The intensity modulation patterns can be derived from the Walsh series by simple linear transformation. [11] W…”

“…It differs from the expansion of the wavefront phase directly which would bring a coupling on the coefficients of the MOW functions. [10,11] The coupling of the coefficients makes it difficult to acquire an analytical solution. In contrast, the expansion form described in the paper can avoid the coupling.…”

“…As discussed above, the intensity modulation produces two kinds of special statements, light on and light off. So a set of relationships between the binary-intensity-modulation patterns and the MOW functions can be built by a simple linear transformation [11] T…”

“…There are two known papers realizing wavefront sensing using a single detector through the measurements of binary aberration modes. [10,11] The most outstanding contribution of them is providing a new way of wavefront sensing with a single detector. It can realize wavefront sensing with enough spatial resolution and speed which opens a great potentiality in adaptive optics system.…”

“…A relationship equation between the coefficients of the MOW functions and their optical fields has been built. However, based on the iterative algorithm [3] or optimization strategy, [11] they can only obtain approximations of the coefficients by solving the equations. The low speed of the algorithms and the uncertain accuracy of the approximations limit the speed of the single detector as well as the method.…”