Ferroelectric liquid-crystal modulator with large switching rotation angle for polarization-independent binary phase modulation

•In this work, we study a ferroelectric liquid crystal (FLC) cell as a phase-only modulator. The novelty of the approach is the use of a FLC cell with a large switching rotation angle close to 90° instead of the typical value used in display applications, which is less than 45∘.•We show that when the LC layer is a half-wave retarder, this device provides a binary π phase modulation for any input state of polarization and with maximum light conversion efficiency, thus being useful even for unpolarized light. This situation is not possible with the common nematic LC modulators or with standard FLC modulators of smaller rotation angles.•The main physico-chemical properties of the liquid crystalline mixture used to fabricate the FLC modulator are studied. In addition, we perform a reverse engineering procedure aimed at verifying the modulator's physical parameters and the binary π-phase modulation.