![]() The use of LEDs in spotlights, and indeed general vehicle lighting (both for Daytime Running Lights, or DRLs, and headlights) has grown considerably over the past decade, as more and more people have taken up the technology, and more investment is being made into the research and development of the LEDs. ![]() Within the LEDs we see in spotlights, the white light is created by using phosphor within the LED, which generates a white light, and makes the LED appear a yellow colour when turned off. We’re not going to go into the physics of it here, but it is simple enough to change the lighting colour based on the semiconductor used – for example red, green and blue. The wavelength (or colour for our example), depends on the ‘band gap’ of the semiconductors used. Within the LED, light is emitted by the recombination of electrons and electron holes within the semiconductor die. LEDs consist of an epoxy casing, anvil and post attached to the anode and cathode leg, a wire bond between the anvil and post, and a semiconductor die. They’ve been around in mass production since the 1960s, and are probably the most efficient and simple of lighting options, however, are probably the newest spotlight technology on the market. Light-Emitting Diodes (or LEDs) are no new thing. This isn’t as critical in spotlights, as most users of these light systems do not run them the entire time the car is on during night hours, unlike headlights.Īs a side thought, HID, or in this specific case arc lighting, is no new thing, being first demonstrated in 1705 by English scientist Francis Hauksbee. This pushes voltage up, often over 30,000 volts, by reducing the current going to the lamp.Īs we said above, vehicle manufacturers are stepping away from HID in their standard lighting systems, in part due to issues with the ballasts wearing out, and also that lighting output can deteriorate by 70 percent over a 10,000 hour usage period. To create and maintain the arc, HID lights require an electrical ballast similar to what your average Fluro lights have (the little white round ‘starters’). Interestingly enough, different noble gasses offer different colours when an arc passes through them. The Xenon gas within the arc tube assists in increasing the brightness of the arc, and also controls the colour of the arc, and thus the colour temperature of the light output. This is housed within a transparent quartz or alumina arc tube, which contains a noble gas most commonly being Xenon. HID lights work by passing a massive amount of volts between two tungsten electrodes, creating an arc. The mid-2000s saw many vehicle manufacturers switch to HID however, they have since (mostly) been replaced by LED headlights, but there are still more than a few HID spotlights on the market, as they work rather well for their intended use. High-Intensity Discharge (or HID) is the newer kid on the block for production lighting. They are still available for automotive use, however, and are still employed by many light manufacturers. They are very inefficient (insofar as power usage vs light output is concerned) and are being phased out for use in your home. The byproduct of the resistance is heat with the filament glowing ‘white-hot’ you create light, which is then reflected out of the spotlight. The light they generate is due to the filament glowing when electricity is passed through it, and the resistance of that filament. The halogen within the bulb assists in keeping the tungsten together and allows the bulb to burn brighter than a standard incandescent bulb, and last longer. Within the sealed bulb is an inert gas mixed with a touch of a halogen gas (usually iodine or bromide). Essentially, the bulbs are sealed (not to be confused with ‘sealed beam’ lights) and have a wire filament (usually made from tungsten) between two pins. Halogen bulbs have been around for a very long time they are the simplest of our lights. We’ll start with the grandad of the lot: Halogen incandescent bulbs.
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