LED lighting has gained just about all the credibility it is
ever going to need after being chosen to illuminate the Mona Lisa
in its new home in the Louvre.
“In the new room where Mona Lisa is there is top
lighting,” Maryline Thorailler of collimator maker Fraen told
Electronics Weekly. “We did a lamp which is lighting
the Mona Lisa from the bottom.”
Several European companies collaborated in the ten month project,
which uses seven coloured LEDs in an undisclosed combination to
produce white light with a colour rendering index of 90 per cent.
The exact colour tint of which was selected after discussions with
the museum’s curators.
“The lamp prepares a beam of light which lights only the
picture, not the frame or the wall,” said Thorailler.
“It needs to compensate for angle and brightness across the
picture.”
Fraen’s Italian operation provided the concentrating
optics which collect light from the LEDs. German optics firm Sklaer
designed and built the colour mixing section, which follows the
collimation stage, and the output projector.
Mixing and projection use a fibre-optic assembly which will be
disclosed later this year. “The light guide mixes the colour
very well,” Sklaer MD Jean Pierre Miras told EW.
“The idea came from a patent with a Russian
company.”
www.fraen.com