Author Affiliations
Abstract
School of Electrical Engineering, Iran University of Science and Technology, Tehran 1684613114, Iran
This Letter presents an original technique to design and synthesize an inhomogeneous asymmetrical lens resulting in a special fan-beam radiation pattern in a wide frequency bandwidth. The vertical and horizontal planes of the fan-beam radiation pattern can be determined separately. Wide angle search and detection are achievable by using this type of lens antenna because of its suitable radiation pattern. The proposed relative index profile is validated by the means of commercial CST software and an FDTD scheme.
160.3918 Metamaterials 080.0080 Geometric optics 080.3630 Lenses 080.5692 Ray trajectories in inhomogeneous media 110.2760 Gradient-index lenses 230.7370 Waveguides Chinese Optics Letters
2016, 14(12): 121601
Author Affiliations
Abstract
Optical tweezers with a low numerical aperture microscope objective is used to manipulate the microspheres at the water-air interface. In this letter, we determine the optimal optical trap for the lateral manipulation of microspheres at a water-air interface. The experimental results show that the trapping force is influenced by the expansion of the trapping beam at the back aperture of the objective. The optimal filling ratio of 0.65 is suggested for lateral optical manipulation at the water-air interface. The lateral trapping forces at the water-air interface are theoretically investigated with the ray-optics model. The numerical results show that the lateral trapping forces can be changed by shrinking the diameter of the trapping laser beam. The numerical results are in accordance with the experimental results.
140.7010 Laser trapping 170.4520 Optical confinement and manipulation 080.5692 Ray trajectories in inhomogeneous media Chinese Optics Letters
2014, 12(1): 011403
Author Affiliations
Abstract
1 Department of Physics, University of Science and Technology of China, Hefei 230026, China
2 Anhui Key Laboratory for Optoelectronic Science and Technology, Hefei 230026, China
3 Hefei National Laboratory for Physical Sciences at the Microscale, Hefei 230026, China
The transverse trapping forces on a dielectric sphere located at an oil-water interface are theoretically investigated with the ray-optics model. The transverse trapping forces rely on the internal property of the particle-interface system, and increase with either the decrease of three phase contact angles at the oil-water interface or the use of oil phase with low refractive index. The numerical results also show that the transverse trapping forces can be improved by either decreasing the numerical aperture of the microscope objective or shrinking the diameter of the trapping laser beam.
光镊 油-水界面 几何光学模型 140.7010 Laser trapping 080.5692 Ray trajectories in inhomogeneous media Chinese Optics Letters
2010, 8(7): 673
