Abstract: Conventional techniques are used to control the flux of an LED element, by modifying a surface of a light emitting element. One type of modification is roughening the surface, to enhance the light extraction efficiency. The degree of modification of the surface is controlled by controlling one or more of the parameters associated with the modification process. A given LED technology will have some minimum flux without modification and some maximum flux with optimal modification. By characterizing the relationship between the parameters of the modifying process and the resultant flux, the parameters of the modification process can be controlled to achieve a desired flux between the minimum and maximum flux achievable by the given LED technology.