Chinese Journal of Liquid Crystals and Displays, Volume. 38, Issue 9, 1178(2023)

Laser scanning device and response speed modulation based on VA liquid crystal

Hong-jun LIU, Cheng-feng QIU*, and Zhao-jun LIU**
Author Affiliations
  • Department of Electrical and Electronic Engineering,Southern University of Science and Technology,Shenzhen 518055,China
  • show less

    In this work, the vertically aligned (VA) liquid crystal devices are prepared on a substrate with serrated ITO electrodes, the laser is coupled into the liquid crystal layer, and the voltage of the ITO electrodes is modulated. The output laser achieves deflection and the deflection angle increases with the increase of voltage until saturation. Under two serrated electrodes with a top angle of 20°, the laser spot deflects by about 4°. At the same time, since the voltage used for driving liquid crystals is an AC signal, by adjusting the minimum driving voltage, which is the bias voltage, the liquid crystal molecules start to rotate from a certain starting angle and are also driven within their fast rotation range, thereby improving the response speed of the liquid crystal molecules.Under the guidance of this strategy, the state and driving speed of liquid crystal molecules are determined by characterizing their polarization state during their rotation. Under the premise of balancing the refractive index and driving speed, the overall response speed of liquid crystal layer molecules under different bias voltages is compared. Under a certain bias voltage, the response time driven by the liquid crystal layer decreases from 55 ms to 2.5 ms, while the relaxation time after power outage decreases from 18 ms to 8.5 ms. This provides a new solution for laser deflection devices using this liquid crystal layer scheme to achieve faster scanning frequency and scanning angle in the future.

    Tools

    Get Citation

    Copy Citation Text

    Hong-jun LIU, Cheng-feng QIU, Zhao-jun LIU. Laser scanning device and response speed modulation based on VA liquid crystal[J]. Chinese Journal of Liquid Crystals and Displays, 2023, 38(9): 1178

    Download Citation

    EndNote(RIS)BibTexPlain Text
    Save article for my favorites
    Paper Information

    Category: Research Articles

    Received: May. 9, 2023

    Accepted: --

    Published Online: Sep. 19, 2023

    The Author Email: Cheng-feng QIU (qiucf@sitan.org), Zhao-jun LIU (liuzj@sustech.edu.cn)

    DOI:10.37188/CJLCD.2023-0174

    Topics