title: Sensor for monitoring the vibration of a laser beam based on holographic polymer dispersed liquid crystal films.
abstract: A continuous multiple exposure diffraction grating (CMEDG) is fabricated holographically on polymer dispersed liquid crystal (PDLC) films using two-beam interference with multiple exposures. The grating is fabricated by exposing a PDLC film to 18 repeated exposure/non-exposure cycles with an angular step of ~10°/10° while it revolves a circle on a rotation stage. The structure of the sample thus formed is analyzed using a scanning electron microscope (SEM) and shows arc-ripples around the center. From the diffraction patterns of the formed grating obtained using a normally incident laser beam, some or all of the 18 recorded arc beams can be reconstructed, as determined by the probing location. Thus, it can be applied for use as a beam-vibration sensor for a laser.
authors.affiliation: Institute of Electro-optical Science and Engineering, National Cheng Kung University, Tainan 701, Taiwan.
authors.forename: Ming Shian
authors.initials: MS
authors.lastname: Li
authors.forename: Shing Trong
authors.initials: ST
authors.lastname: Wu
authors.forename: Andy Ying-Guey
authors.initials: AY
authors.lastname: Fuh
mesh_terms: D004867:Equipment Design; D019544:Equipment Failure Analysis; D006696:Holography / Q000295:instrumentation*; D007834:Lasers; D050866:Liquid Crystals / Q000737:chemistry*; D008567:Membranes, Artificial; D010783:Photometry / Q000295:instrumentation*; D011108:Polymers / Q000737:chemistry*; D014159:Transducers; D014732:Vibration
chemical_list: D008567:Membranes, Artificial; D011108:Polymers