We investigate the performance and capability of a holographic modal wavefront sensor (HMWS) that is based on a multiplexed phase computer-generated hologram (MPCGH). The theoretical treatments of the HMWS are presented with scalar diffraction approximations and Fourier analysis. Several MPCGHs have been designed with different linear carrier frequencies, by using of the multiplexed coding scheme we have proposed, and by coding some common Zernike modes. The numerical simulation is carried out to investigate the performance of the HMWS to detect particular aberration mode(s), by considering the effect of different carrier frequency selections and the capability of coding a large number of modes. The results exhibit the expected characteristics of a corresponding symmetric spot pair, and indicate that the wavefront distorted by a particular Zernike mode(s) can be retrieved immediately through solving the amplitude of each mode coded in MPCGHs through the response curves of the HMWS.

We propose an approach for implementing a modal wavefront sensor using a binary phase-only multiplexed computer-generated hologram (BPMCGH). To simplify the coding and fabricating processes, a model based on tilt plane reference waves and an effective coding scheme for BPMCGH have been developed. The necessary number of subholograms to be recorded or coded is significantly reduced, from two or even more to just one per aberration mode, accordingly. The numerical and experimental demonstration results are presented and discussed and show that this approach is convenient for producing a BPMCGH and efficient for sensing the aberration modes.

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We introduce a modal wave front sensing technique of using binary computer generated hologram (BCGH) and a coding approach. Several types of Zernike aberrations were encoded into the BCGH using this method. Light wave front was modulated by BCGH and single Zernike aberration mode respectively, and the holographic modal wavefront sensor was simulated and verified. The results show that, wave front distorted by a special aberration mode, after modulated by the BCGH, can be transformed into beams which have a relative intensity, which can reflect the change trend of the aberration coefficients in the unknown wavefront.

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