Lumileds is to cut the number of colour 'bins' in its white LED range following the introduction of its Lumiramic phosphor technology.

"An immediate reduction in the number of white colour bins for the company's warm white Luxeon Rebel has been implemented," said Lumileds.

From one or two colour tint bins either side of the black body radiation curve, the firm will now just have a single row of bins on the curve.

"The binning of white LEDs is a work-around to manage the variation in white colour and tint that are the result of today's manufacturing processes," said Lumileds. "The only way most manufacturers can consistently produce sufficiently large quantities of the desired bins for general lighting has been to increase the volume of white LEDs manufactured and discard those that don't fit in the desired colour spaces."

Colour coding LED info
	Driving into the blue
	Organic - grow your own
	Green chandeliers
	Into the black?
	Display Trilogy
	Headlight glare
	Phosphorous
	Sensing light
	Grey area
An alternative look at the hues and shades of LED technology

White LEDs for lighting are actually a blue LED with a blue to yellow conversion phosphor layer on top.

Lumiramic is a technology that no longer deposits liquid phosphor on to the blue die.

Instead, a separately-made flake of pre-characterised solid phosphor is installed on the underlying die.

By measuring the emission of the bare die, a flake can be selected to guarantee a hit on the black body curve.

"It will result in a single row of white bins along the black body locus," said Lumileds. "Each bin will be sized to represent a total space no more than three MacAdam ellipses."

See also: Electronics Weekly's roundup of content related to LEDs, with a special focus on both white LEDs and coloured LEDs:

LED technology - White LEDs

LED technology - Coloured LEDs

LED technology - LEDs general