LED Lens for Rectangular Beam with Small Divergence Angles

Abstract

We have designed a new TIR(Total Internal Reflection) structure for generating an LED lens which can produce a rectangular beam with small divergence angle in two perpendicular directions for an optical guidance system. The lens can control the divergence angle in the horizontal direction to be a small value of about 8° with a 1 mm × 1 mm LED source, also in the vertical direction it can be about 7°, with optical collection efficiency higher than 0.83. After the lens is manufactured, the work demonstrates that the lens is suitable for an optical guidance system.

Underwater optical wireless communications, networking, and localization: A survey

“…where A j is the receiver aperture area of node j and θ i is the beam divergence angle of transmitter node i. In order to concentrate the transmitted energy on receiver aperture, the divergence angle of laser-diodes are generally designed to be a few milliradians or less [164] whereas typical LEDs can have divergence angles less than 140 milliradians to diffuse light to wide angles [165]. Accordingly, received power can be formulated as a product of transmission power, transceivers' efficiency, telescope gain, and path loss factor, i.e.,…”