Modal wavefront sensor employing stratified computer-generated holographic elements

• Modal wavefront sensor consisting of stratified computer-generated holographic elements (SCGHEs).
• Each computer-generated hologram (CGH) is coded with particular single Zernike aberration mode and parallel to one another with a slight separation.
• Characterize wavefront sensing operation with single CGH, and further with SCGHEs.
• Investigate four situations in which the CGH is treated as the type of continuous amplitude, continuous phase, binary amplitude, and binary phase.
• Continuous amplitude, continuous phase, binary amplitude-type SCGHEs are more feasible to detect specified aberration modes

We describe a modal wavefront sensor that uses a stratified computer-generated holographic element (SCGHE). Each computer-generated hologram (CGH) in the SCGHE is coded with a single particular Zernike aberration mode, and arranged in parallel to one another with a slight separation. Four kinds of CGH, including continuous amplitude CGH, continuous phase CGH, binary amplitude CGH, and binary phase CGH are numerically analyzed. And the wavefront sensing principle is characterized firstly with a single CGH, and then with the SCGHE. The results show that wavefront sensor with the first three CGHs are feasible to detect specified Zernike aberration modes. Furthermore, some comparisons are provided to suggest an optimal choice in the actual implementation of sensor design.