Title :
A novel optoelectronic tweezer using light induced dielectrophoresis
Author :
Chiou, Pei Yu ; Chang, Zehao ; Wu, Ming C.
Author_Institution :
Dept. of Electr. Eng., California Univ., Los Angeles, CA, USA
Abstract :
We demonstrate a novel optoelectronic tweezer using light induced dielectrophoresis mechanism to optically trap and transport micro particles with optical power in the μW range. This device consists of two pattern-less surfaces: a bottom glass substrate coated with photoconductive material and a top transparent indium-tin-oxide (ITO) glass. To achieve optical trapping, we sandwich the liquid-immersed micro particles between these two surfaces and supply an ac electric bias. A 633-nm He-Ne laser focused by a 40x objective lens is used to transport the particles. Negative dielectrophoretic trapping is demonstrated in this paper. Our experiment results show that optical beam with power as low as 1 μW is sufficient to transport 25-μm-diameter latex particles at a speed of 4.5 μm/sec. The transport speed increases with higher optical power. A maximum speed of 397 μm/sec is observed at 100 μW.
Keywords :
bio-optics; biological techniques; cellular biophysics; electrophoresis; laser beams; lenses; optical focusing; optical glass; optical polymers; optoelectronic devices; photoconducting materials; radiation pressure; 100 muW; 25 mum; 397 mum/s; 4.5 mum/s; 40x objective lens; 632 nm; He-Ne laser; ITO; InSnO; SiO2; ac electric bias; glass substrate; latex particles; light induced dielectrophoresis; liquid-immersed microparticles; microparticle transport; negative dielectrophoretic trapping; optical beam; optical focusing; optical trapping; optoelectronic tweezer; photoconductive material; transparent indium-tin-oxide glass; Biomedical optical imaging; Charge carrier processes; Dielectrophoresis; Electric fields; Electromagnetic wave absorption; Glass; Indium tin oxide; Optical polymers; Optical surface waves; Photoconducting materials;
Conference_Titel :
Optical MEMS, 2003 IEEE/LEOS International Conference on
Print_ISBN :
0-7803-7830-X
DOI :
10.1109/OMEMS.2003.1233441
