This video shows the trapping efficiencies as a function of the incidence angle for a ray impinging on a spherical particle (water, refractive index: np = 1.33) in air (nm = 1.00). On the right side the scattering process as a function of the incidence angle is represented, on the left side the calculated scattering, gradient and total trapping efficiency.
Agnese Callegari, Mite Mijalkov, A. Burak Gököz, and Giovanni Volpe, “Computational toolbox for optical tweezers in geometrical optics,” J. Opt. Soc. Am. B 32, B11-B19 (2015). http://dx.doi.org/10.1364/JOSAB.32.000B11