Abstract
A thin layer of liquid crystal can be used as a simple two‐dimensional detector of ultrasound. The acoustic beam disturbs the molecular alignment of the liquid crystal, which allows changes in light transmission when the cell is placed between crossed polarizers. Most studies have concentrated on nematic liquid crystals with optic axis along the layer normal. We have studied the acoustic response of a new type of cell developed for electro‐optic displays [D. Berreman and W. Heffner, J. Appl. Phys. 52, 3032–3039 (1981)], which is a twisted nematic with oblique attachment angle at the layer surfaces. We find that this cell is generally more sensitive than the homeotropic nematic and has a faster response time. The cell has the additional feature of having two stable molecular configurations that satisfy the same boundary conditions. Under certain conditions the acoustic beam can drive the system from one state to the other, providing a memory feature for the detector.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
