| 1. |
|
|
| 2. |
- Engström, David, 1976, et al.
(författare)
-
Analog low-loss full-range phase modulation by utilizing a V-shaped switched ferroelectric liquid-crystal cell in reflective mode
- 2006
-
Ingår i: Optics Letters. - 0146-9592 .- 1539-4794. ; 31:19, s. 2906-2908
-
Tidskriftsartikel (refereegranskat)abstract
- We have studied the analog (V-shaped switching) mode in ferroelectric liquid crystals in reflective mode for analog phase modulation applications. We have found that several combinations of cell thicknesses and input polarization states exist for which near-lossless analog phase modulation with a range of ~2π rad is obtained, and we demonstrate one such combination experimentally. Despite a slight deviation from the ideal conditions, e.g., the tilt angle was 38° instead of the desired 45°, virtually pure 1.6π rad phase modulation was obtained; the measured values agree very well with our numerical simulations of the real device.
|
|
| 3. |
|
|
| 4. |
- Engström, David, 1976, et al.
(författare)
-
Three-level phase modulator based on orthoconic antiferroelectric liquid crystals
- 2006
-
Ingår i: Optics Letters. - 0146-9592 .- 1539-4794. ; 31:21, s. 3158-3160
-
Tidskriftsartikel (refereegranskat)abstract
- Surface-stabilized orthoconic antiferroelectric liquid crystals (OAFLCs) have a director tilt of θ=45° and are, with no field applied, negatively uniaxial with the optic axis perpendicular to the cell substrates. We demonstrate that OAFLCs can be utilized to achieve lossless phase modulation with three almost equidistant phase levels. This turns out to be true also for polymer-stabilized OAFLCs, where the polymer network increases the switching speed of the device without affecting the phase modulation appreciably.
|
|
