There&#x27;s another aspect to this development.  One benefit of incandescent lamps vs. CFL or LED is superior CRI (color rendering index).<p>CFL&#x2F;LED lamps produce output having a discontinuous spectrum, fluorescents with prominent green and LEDs blue emission.  Consequently these light sources can be much less desirable where accurate color rendering is important, for example critical color matching, art galleries&#x2F;museums, etc.<p>I&#x27;ve found it difficult to replace continuous spectrum sources with LED lights in particular.  The latter are much more energy efficient and have greater useful life span, but unsuited to photography, etc., where quality of color rendering is crucial.<p>Quite likely there&#x27;s a large enough market for improved incandescent lamps to warrant further development.