This invention solves the problem of color variance between light emitted from an LED tube in different directions. The invention proposes a cover part surrounding the light source having different phosphor thickness in two different light emitting directions of the light source.
This invention is related to LED lights. Existing lights have different luminous intensity in multiple directions resulting in emission of various light colors. Currently, lights use phosphor cover with non-uniform thickness to solve this problem, but light direction is changed when cover thickness is non-uniform and also, changes light intensity in different directions.
Proposed LED lights have a light source arranged on a substrate and a cover spaced away from the light source. The cover is designed in two parts with different thickness in different directions keeping their sum constant in all directions so that uniform light intensity is achieved. First part has a substrate, and phosphors are arranged on outermost layer and second part is made from a substrate material but free from phosphor, so that uniform chroma and light-emitting performances can be obtained. Proposed LEDs are cost effective and can be fabricated using a bi-material injection process. Applications: The invention may be implemented in LED lights, LED tubes, outdoor LED lights, LED luminaires, LED facility lights, decorative LED lights etc. Companies: This invention may be implemented by lighting companies.