Researchers have significantly improved the response time of a 4 mm-aperture hole-patterned liquid crystal (HLC) lens with doping of N-benzyl-2-methyl-4-nitroaniline (BNA) and rutile titanium dioxide nanoparticle (TiO2 NP) nanocomposite.
The proposed HLC lens provides the focus and defocus times (related to the wavefront bending speed) that are 8.5× and 14× faster than the pristine HLC lens, respectively, reaching the order of a millisecond. The synergistic effect of BNA and TiO2 NP nanocomposite induces a 78% decrement in the viscosity of pristine LC mixture that significantly shortens the focus and defocus times of the HLC lens.
The remarkable decrement in viscosity is due to spontaneous polarization electric fields from the permanent dipole moments of the additives. Besides, the strengthened electric field surrounding TiO2 NP assists in decreasing the focus time of HLC lens. The proposed HLC lens has a higher tunable focus capability than the pristine HLC lens within a smaller voltage interval.