Wavelength-converting LED

摘要

A wavelength-converting LED can include a light-emitting section in which an exciting element emits a blue or ultraviolet light. A fluorescent material that has a mean particle diameter D₅₀ ranging from 5 mum to 20 mum and that can convert at least part of the light emitted from the exciting element into light having a wavelength longer than an exciting wavelength, can be incorporated into the LED. A dispersing agent with a mean particle diameter D₅₀ not less than 1/10 of the mean particle diameter D₅₀ of the fluorescent material is preferably incorporated in the LED. A binder base material can be arranged to contain the fluorescent material, the dispersing agent and a binder therein. The sum of the weights of the fluorescent material and the dispersing agent is preferably in the range of 20% to 60% by weight of said binder base material to prevent the fluorescent material from precipitating in the binder base material upon curing.