An off-axis, reflective system for uniform near-field illumination in optical microscopy

Abstract

In traditional optical microsopy the uniformity of off-axis illumination is poor. In this paper we propose a novel LED optical system for near-field illumination in microscopy. The system includes a LED light source, an optical collimator and a freeform, micro-reflective lens array. The Monte Carlo method is used to simulate the system. The simulation results show that the illumination uniformity can be better than 85% in the observation zone. The optical system can be put at the side of the main optical axis of the microscope. The illumination uniformity is not varied when the observation distance changes so it has good stablilty.

Freeform beam-shaping system design with Monge-Ampère equation method

“…Freeform optical surfaces transcend traditional optical surfaces with rotational or translational symmetry. Due to the high degrees of freedom, freeform optical surfaces can be used to create more efficient and compact designs that offer superior performance [1] and can be applied to road illumination [2][3][4], laser beam-shaping [5][6][7][8], microscopic illumination [9][10][11], etc. Designing a freeform beam-shaping system is a challenging inverse problem and can be simplified by the ideal light source assumption, which assumes the etendue of an incident beam equals zero.…”