Polarization independent Fabry-Pérot filter based on polymer-stabilized blue phase liquid crystals with fast response time

Abstract

This work demonstrates a polarization-independent electrically tunable Fabry-Pérot (FP) filter that is based on polymer-stabilized blue phase liquid crystals (PSBPLCs). An external vertical electric field can be applied to modulate the effective refractive index of the PSBPLCs along the optical axis. Therefore, the wavelength-tuning property of the FP filter is completely independent of the polarization state of the incident light. The change in the birefringence in PSBPLCs is governed by Kerr effect-induced isotropic-to-anisotropic transition, and so the PSBPLCs based FP filter has a short response time. The measured tunability and free spectral range of the FP filter are 0.092 nm/ V and 16nm in the visible region, and 0.12nm/ V and 97nm in the NIR region, respectively, and the response time is in sub-millisecond range. The fast-responding polarization-independent electrically tunable FP filter has substantial potential for practical applications.

Self-Organized 3D Photonic Superstructure: Blue Phase Liquid Crystal

“…tens of milliseconds. BPLCs are therefore considered as a promising alternative to nematics for electro-optic applications, including: gratings [113][114][115], lenses [113,116], interferometric filters [117,118], attenuator [119] and displays [86,120,121]. Most of these devices are made of PSBPs because the addition of polymer network could suppress the slow electrostriction effect (cf.…”

“…The PSBP can be integrated either inside or outside an optical cavity to realize an electrically tunable interferometric filter. By sandwiching a PSBP between two aluminium mirrors, a tunable Fabry-Pérot filter was thus fabricated [117]. Owing to the high reflectivity of the mirrors and optical transparency of the PSBP across an extremely broad spectrum, the etalon could be operated in both the visible and near infrared regions.…”

Robust and monodomain-like polymer-stabilized simple cubic blue phase with red, green, and blue reflective colors

“…For this reason, polymer stabilization methods have frequently been employed to expand the temperature ranges at which cubic BPs can exist [3,[7][8]. Although polymer-stabilized (PS) BPI samples possessing wide temperature ranges (several tens of degrees Celsius), however, have been reported by several groups [8][9][10], such wide temperature ranges for PS simple cubic blue phase (PSBPII) samples have been rarely achieved [7]. This is because the temperature ranges in which a pure BPII appears are narrowly compared with those in which pure BPI appears, and as such, in situ polymerization is more difficult in BPII than in BPI.…”

MWIR/LWIR filter based on Liquid–Crystal Fabry–Perot structure for tunable spectral imaging detection

“…Therefore, the resonance wavelength of the LC-FP filter will be varied with the voltage driving-signal. It is reported that the electrically tunable LC-FP filter working in the visible [11,12] and near-infrared [13], has also been developed successfully.…”