Wide emitting lens for LED useful for backlighting

摘要

Lenses and certain fabrication techniques are described. A wide-emitting lens refracts light emitted by an LED die to cause a peak intensity to occur within 50-80 degrees off the center axis and an intensity along the center axis to be between 5% and 33% of the peak intensity. The lens is particularly useful in a LCD backlighting application. In one embodiment, the lens is affixed to the backplane on which the LED die is mounted and surrounds the LED die. The lens has a hollow portion that forms an air gap between the LED die and the lens, where the light is bent towards the sides both at the air gap interface and the outer lens surface interface. The lens may be a secondary lens surrounding an interior lens molded directly over the LED die.