This study aimed to determine the effect of sample thickness on optical trapping towards water-air interface. 3 µm polystyrene bead was diluted in deionised water and transferred to special test cell design to form 18, 70 and 141 µm. Bead was trapped by 975 nm laser from 20 to 220 kW/cm2 from the bottom glass-water interface towards water-air interface. The result showed that the bead is more confined with smaller effective radius in higher water thickness.   ..

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The study aims to optically trap a single chloroform (CHCl3) microdroplet in water using optical tweezers. The study also investigates the effect of the preparation procedure by sonication on the chloroform microdroplet size and its stability in water. This microdroplet can potentially act as a carrier containing active molecules and for sensor applications in a fluid. The chloroform is sonicated in deionized water to produce a chloroform microdroplet solution. The size of the resultant microdroplets is observed under the optical microscope. The stability of the chloroform microdroplets in water was studied by monitoring the absorption spectra within a specified duration of time for 1 hour. A single chloroform microdroplet in the water is trapped using a 976 nm continuous laser beam with optical tweezers. The finding shows that the average size of the produced chloroform microdroplets does not vary significantly when the sonication time is less than 10 minutes. Furthermore, Chloroform .....

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The study aims to formulate the production of 4-cyano-4’-pentylbiphenyl (5CB) microdroplets within a suitable range to be optically trapped, to optically trap a single 5CB microdroplet in water within a suitable size range, to optically micro-control the microdroplet using a circularly polarized laser, and to quantitatively determine factors affecting the optical manipulation of the microdroplet. 0.5 μL 5CB was mixed with the deionized water and sonicated to produce bipolar and radial 5CB microdroplet suspensions. The 5CB microdroplet was observed under optical microscopy and its size distribution was measured using ImageJ, while its stability was measured using UVVis spectroscopy. A linearly polarized laser beam of 976 nm wavelength was used to optically trap a single 5CB microdroplet in water at a specific laser power density. A circularly polarized laser beam was used to optically trap a single 5CB microdroplet to study its orientation control, rotatability control, an.....

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