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A LED to replace
50W halogens?
Elsewhere in this issue (and indeed previous issues of SILICON CHIP)
we rail against the huge energy wastage of all-too-popular halogen
downlights). Perhaps their days are numbered . . .
J
ust over 12 months ago (June 2006), we brought you
news of a (then!) super-bright LED whose brightness
exceeded that of a 20W halogen. With rapid advance ments in the LED field, the next brightness hurdle – that
of the 50W halogen – has been jumped.
Osram has developed a light-emitting diode (LED)
spotlight that achieves an output of more than 1000 lumens.
That’s brighter than a 50W halogen lamp, making the device
suitable for a broad range of general lighting applications.
The Ostar Lighting LED, scheduled for release within
months, can provide sufficient light for a desk from a height
of two metres, for example. Its small size also enables the
creation of completely new lamp shapes.
A lumen (lm) is the unit of measurement for the amount
of light emitted by a light source. A typical 60W light bulb
emits 730lm, while a 50W halogen lamp has an output of
approximately 900lm. To achieve the 1000lm output of
the tiny Ostar Lighting LED, Siemens’ Osram subsidiary
managed to integrate six high-performance LED lighting
chips into the unit’s small housing. Each chip has an
area of only one square millimetre, which makes for very
concentrated overall luminosity.
Different types of LEDs are used today in various areas,
for example as background lighting in cell phone displays,
as well as in car turn-signal lights, brake lights and daytime
running lights. They’re also rapidly replacing incandescent
bulbs in traffic control lights. The benefits are obvious.
The LEDs are extremely small and consume little energy
because they efficiently convert electricity into light.
The Ostar Lighting LED, for example, produces 75
lumens per watt at a current of 350mA. By comparison, a
standard incandescent lamp, at around 12-15 lumens per
watt, converts only a fraction of the electricity supplied
into light. The rest is lost as heat. Halogen downlights are
marginally better at about 18-25 lumens per watt. An even
better idea of the efficiency of the Ostar LED is that its 12V,
50W halogen competitor requires a 4A supply.
In addition, LED lamps last around 10 times longer than
halogen lamps and 50 times longer than incandescent
lamps, thereby helping to significantly reduce maintenance
costs. They contain no lead or mercury, which makes them
very environmentally friendly.
Until now, LEDs have been unsuited for room lighting
because they weren’t bright enough. The Ostar Lighting
LED marks a big step forward – we could soon see lots of
LEDs in home lighting.
siliconchip.com.au
Osram has developed a LED spotlight that achieves an
output of more than 1000 lumens for the first time. That’s
brighter than a 50W halogen lamp but without the heat,
thereby making the device suitable for a broad range of
general lighting applications. The Ostar Lighting LED will
be launched on the market this year.
Osram has already supplied a Migros supermarket in
the Swiss canton of St. Gallen with 18,000 Golden Dragon
LEDs, which have a lower output than the Ostar Lighting
units.
These LEDs emit neither UV rays nor heat, which means
they have virtually no negative impact on delicate grocery
items such as milk, meat, fruit and vegetables.
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