The optical field parameters in the “photonic nanojet” area formed near the surface of dielectric spherical microparticles irradiated with a focused laser beam are theoretically considered. The influence of the beam waist on the “photonic nanojet” parameters (length, width, intensity) is investigated. The optimum ratio between key parameters of the photonic flux is shown to be implemented when the beam waist and particle diameter are on the same scale.
light scattering, microparticle, focused laser beam, photonic nanojet
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