lights on a car say a great deal about the design. Good visibility is
essential for safe driving at night, and is also necessary to be seen in
poor daylight conditions. In the early days of car production acetylene gas lamps
were used at night. Can you imagine that today?
Edison (USA) and John Swan (UK) came along to give us the incandescent bulb, which
made it possible to drive fast cars at night. John Swan is thought to
have beaten Edison to the punch, but mysteriously fell from a train,
leaving the path clear for the well known American
inventor. Today we have LED
lighting, which is not only brighter and smaller for the same light
output, but also more efficient. Yes. It's also a boy racers dream come
true. Not to mention the joy it brings to truckers and custom builders generally. Let there
view: The rear of the car now has the makings of the cover that
protects the loading mechanism. This is known affectionately as the
"fanny-pack" in the workshop (US rear end, not lady-hump) - mainly because nobody really
liked the idea of a protrusion to the rear, where we are striving for
elegance . The bulge though is necessary. But the artists will now try to
blend the necessary 'back-pack' in to make it a feature as part of the lighting. August 28 2014.
a close up view of the rear panel, which is only really there as something
to work from. The "back-pack" will eventually blend into the
tail light and indicators. So far it's a blank canvas. The unit is not
shown here fixed, but is rather placed conveniently for the body man to
install lower down, as per the diagrams below.
Rear view of the DC50 drawn in AutoCad, showing a proposed layout for
the indicators, side and brake lights - all LED. The indicators are on
the rear quarter panel, so are visible from the side just as much as to
the rear. The boot-lid spoiler carries a line of LEDs. Other driving
lights may be added. BELOW: Same rear view of car, but rendered in blue.
The Ecostar DC50
features the Bluebird™ cartridge recharging system: System Bluebird.
This advanced vehicle is a fitting tribute to Donald
Campbell's double, land and water world speed records in 1964.
Adding to the accolade, this prototype uses direct current motors (DC)
rated at 50Kw.
EMITTING DIODES - LEDs
A light-emitting diode (LED)
special (two-lead) kind of diode that glows when electricity passed
through it; it is a semiconductor light source. An LED resembles a basic pn-junction diode, which emits light when activated. When a fitting voltage is applied to the leads, electrons are able to recombine with electron holes within the device, releasing energy in the form of photons. This effect is called
electro-luminescence, and the color of the light (corresponding to the energy of the photon) is determined by the energy band gap of the semiconductor.
An LED is often small in area (less than 1 mm2) and integrated optical components may be used to shape its radiation pattern.
Appearing as practical electronic components in 1962, the earliest LEDs emitted low-intensity infrared light. Infrared LEDs are still frequently used as transmitting elements in remote-control circuits, such as those in remote controls for a wide variety of consumer electronics. The first visible-light LEDs were also of low intensity, and limited to red. Modern LEDs are available across the visible, ultraviolet, and infrared wavelengths, with very high brightness.
Early LEDs were often used as indicator lamps for electronic devices, replacing small incandescent bulbs. They were soon packaged into numeric readouts in the form of seven-segment displays, and were commonly seen in digital clocks.
Recent developments in LEDs permit them to be used in environmental and task lighting. LEDs have many advantages over incandescent light sources including lower energy consumption, longer lifetime, improved physical robustness, smaller size, and faster switching. Light-emitting diodes are now used in applications as diverse as aviation lighting, automotive headlamps, advertising, general lighting, traffic signals, and camera flashes. However, LEDs powerful enough for room lighting are still relatively expensive, and require more precise current and heat management than compact fluorescent lamp sources of comparable output.
LEDs have allowed new text, video displays, and sensors to be developed, while their high switching rates are also useful in advanced communications technology.
LED can have a relatively long useful life. estimates 35,000 to 50,000 hours of useful life, though time to complete failure may be longer. Fluorescent tubes typically are rated at about 30,000 hours, and incandescent light bulbs at 1,000–2,000 hours
Conventional incandescent light bulbs typically are about 15 lumens per watt and the compact fluorescent lamps are about 50 lumens per watt.
Manufacturer of high intensity and high power LED module for General lighting
applications and energy efficient lighting produce units that typically
give 80 lumens per watt.
Automotive headlamp applications using light-emitting diodes (LEDs) have been undergoing very active development since 2004. The first series-production LED headlamps were factory-installed on the Lexus LS 600h / LS 600h L presented in 2007 for 2008 models. Low beam, front position light and sidemarker functions are performed by LEDs; high beam and turn signal functions use filament bulbs. The headlamp is supplied by Koito. Full-LED headlamps supplied by AL-Automotive Lighting were fitted on the 2008 V10 Audi R8 sports car except in North America. The Hella headlamps on the 2009 Cadillac Escalade Platinum became the first US market all-LED headlamps.
Designs as of MY2010, such as those available as optional equipment on the 2010 Toyota Prius, give performance between halogen and HID
headlamps, with system power consumption slightly lower than other headlamps, longer lifespans and more flexible design possibilities. As LED technology continues to evolve, the performance of LED headlamps is predicted to improve to approach, meet, and perhaps one day surpass that of HID headlamps.
The limiting factors with LED headlamps presently include high system expense, regulatory delays and uncertainty, and logistical issues created by LED operating characteristics. As a semiconductor, the performance of an LED is dependent on its temperature; a given diode will produce more light at a low temperature than at a high temperature. Thus, in order to maintain a constant light output, the temperature of an LED headlamp must be kept relatively stable. LEDs are commonly considered to be low-heat devices due to the public's familiarity with small, low-output LEDs used for electronic control panels and other applications requiring only small amounts of light; however, LEDs actually produce a significant amount of heat per unit of light output. Rather than being emitted together with the light as is the case with conventional light sources, an LED's heat is produced at the rear of the emitters. Unlike incandescent and HID bulbs, LEDs are damaged by high temperatures; prolonged operation above the maximum junction temperature will permanently degrade the LEDs and ultimately shorten the device's life. The need to keep LED junction temperatures low at high power levels requires thermal management measures such as heatsinks or cooling fans which are typically quite expensive.
Additional facets of the thermal issues with LED headlamps reveal themselves in cold ambient temperatures. Not only can excessively low temperatures lead to the LED's light output increasing beyond the regulated maximum, but heat must in addition be effectively applied to thaw snow and ice from the front lenses, which are not heated by the comparatively small amount of infrared radiation emitted forward with the light from LEDs.
LEDs are increasingly being adopted for signal functions such as parking lamps, brake lamps and turn signals as well as daytime running lamps, as in those applications they offer significant advantages over filament bulbs with fewer engineering challenges than headlamps pose.
lighting for cars, now extremely popular as replacements to filament
bulbs, for street cred and to improve lighting with energy savings.
Those shown above in the top row are aftermarket units. Those in the
bottom row are the Audi front driving lights and Porsche rear light
Efficient lighting is needed for sustainable architecture. In 2009, a typical 13-watt LED lamp emitted 450 to 650
lumens, which is equivalent to a standard 40-watt incandescent bulb. In 2011, LEDs have become more efficient, so that a 6-watt LED can easily achieve the same results. A standard 40-watt incandescent bulb has an expected lifespan of 1,000 hours, whereas an LED can continue to operate with reduced efficiency for more than 50,000 hours, 50 times longer than the incandescent bulb.
In the US, one kilowatt-hour (3.6 MJ) of electricity currently causes an average 1.34 pounds (610 g) of CO2
emission. Assuming the average light bulb is on for 10 hours a day, a 40-watt bulb will cause 196 pounds (89 kg) of CO2 emission per year. The 6-watt LED equivalent will only cause 30 pounds (14 kg) of CO2 over the same time span. A building’s carbon footprint from lighting can therefore be reduced by 85% by exchanging all incandescent bulbs for new LEDs if a building uses only incandescent bulbs.
In practice, most buildings that use a lot of lighting use fluorescent lighting, which has 22% luminous efficiency compared with 5% for filaments, so changing to LED lighting would give only 34% reduction in electrical power and carbon emissions.
The reduction in carbon emissions depend on the source of electricity. Nuclear power in the United States produced 19.2% of electricity in 2011, so reducing electricity consumption in the U.S. reduces carbon emissions more than in France (75%
nuclear electricity) or Norway (almost entirely hydroelectric).
lighting is used on stage to great effect, to produce some stunning
LED - OLED
The Organic LED is made of a layer of organic
electro-luminescent material with a p/n junction sandwiched between to electrodes. At least one of the electrodes is transparent so the photons can escape.
The semiconductor in an OLED is organic which means it contains carbon. The OLED uses one of two kinds of compounds: polymers or 'small molecule'.
As of 2012, OLEDs were producing 50 lumens per watt.
OLEDs are more commonly used for short distance indoor lamps because it
produces a diffused light. They are also used for media devices and
large televisions or computer monitors.
The advantages are that the units are lighter than traditional LEDs and can be made thinner.
OLEDs can provide a more energy efficient alternative to LCD computer and
The disadvantage is that the cost of OLEDs is still high and each unit produces less lumens than a normal LED.
DC50 LINKS A-Z INDEX
traffic signal lighting is not only brighter, but the units also use
less electricity and will not need bulb replacements nearly so often.
LINKS & REFERENCE
Is Tech Target light-emitting-diode-LED
Tech Center LEDs and oleds
UK electronics components
Stuff Works led