Dye-Doped Electrically Smart Windows Based on Polymer-Stabilized Liquid Crystal

Here we report the fabrication of dye-doped polymer-stabilized liquid crystals (PSLC)-based smart windows. The effect of dye doping on PSLC contrast was investigated. Non-dichroic dye tints the PSLC sample in both off- and on-state, which is not beneficial for increasing its off/on contrast. The sample doped with dichroic dye shows a slight color in the off-state and strong color in the on-state, resulting in an enhanced contrast, which attributed to orientation dependent absorption of dichroic dyes. Furthermore, we blended non-dichroic dye and dichroic dye who have complementary absorption together into PSLC mixture. The sample is almost colorless in the off-state due to the subtractive process, while colored in the on-state. The contrast is further enhanced. The results show that the proposed multi-dye-doped PSLC device has high visual contrast and fast response time, making it attractive for applications in light management and architectural aesthetics.

Download Full-text

Low-voltage-modulated laser based on dye-doped polymer stabilized cholesteric liquid crystal

Optical Materials Express ◽

10.1364/ome.3.000519 ◽

2013 ◽

Vol 3 (4) ◽

pp. 519 ◽

Cited By ~ 20

Author(s):

Bo-wei Liu ◽

Zhi-gang Zheng ◽

Xu-chang Chen ◽

Dong Shen

Keyword(s):

Liquid Crystal ◽

Low Voltage ◽

Cholesteric Liquid Crystal ◽

Polymer Stabilized ◽

Doped Polymer

Download Full-text

Smart Window with Active-Passive Hybrid Control

Materials ◽

10.3390/ma13184137 ◽

2020 ◽

Vol 13 (18) ◽

pp. 4137

Author(s):

Heng-Yi Tseng ◽

Li-Min Chang ◽

Kuan-Wu Lin ◽

Cheng-Chang Li ◽

Wan-Hsuan Lin ◽

...

Keyword(s):

Liquid Crystal ◽

Voltage Pulse ◽

Hybrid Control ◽

Cholesteric Liquid Crystal ◽

Low Frequency ◽

Operating Mode ◽

Smart Window ◽

Smart Windows ◽

Dichroic Dye ◽

Scattering State

Dimming and scattering control are two of the major features of smart windows, which provide adjustable sunlight intensity and protect the privacy of people in a building. A hybrid photo- and electrical-controllable smart window that exploits salt and photochromic dichroic dye-doped cholesteric liquid crystal was developed. The photochromic dichroic dye causes a change in transmittance from high to low upon exposure to sunlight. When the light source is removed, the smart window returns from colored to colorless. The salt-doped cholesteric liquid crystal can be bi-stably switched from transparent into the scattering state by a low-frequency voltage pulse and switched back to its transparent state by a high-frequency voltage pulse. In its operating mode, an LC smart window can be passively dimmed by sunlight and the haze can be actively controlled by applying an electrical field to it; it therefore exhibits four optical states—transparent, scattering, dark clear, and dark opaque. Each state is stable in the absence of an applied voltage. This smart window can automatically dim when the sunlight gets stronger, and according to user needs, actively adjust the haze to achieve privacy protection.

Download Full-text