LED vs. Halogen vs. Xenon – Which Is Best?
For years, the headlight technology in the world has been advancing. In the recent past, the growth curve has been exponential. So much so that it has proven to be slightly harder for many to keep up with the technology available. But even with their ignorance, many, if not all still want to get the best there is on the market.
But before a decision can be made, you first need to pump your brain with the relevant knowledge that will allow you to make the right decision. Before diving into it headfirst, it is worth noting that some of the newest cars in the market, models from BMW and Audi have started experimenting on laser headlights which suggests that this is the future of vehicle headlights.
In this piece however, we shall concentrate our efforts on comparing the common headlights currently. These are Halogen, LED and Xenon headlights. We shall discuss every technology as well as the major advantages and disadvantages that there are.
These are the most recent piece of technology that we have in the headlight industry. Instead of using gasses and filaments, these headlights make use of tiny diodes that produce light when the current excites electrons.
They as such need to have a low amount of power to work but in turn produce a high and significant amount light and some amount of heat. This requires a heat control system to control everything since when the system fails the entire electronic system does too and not only the headlights and close components.
How They Work
These Light Emitting Diodes make use of diodes to produce light. The diodes produce light when they are connected to a circuit board. When connected to a circuit the LEDs tend to produce a high number of photons outwards. The LED headlights are made with plastic bulbs which help to concentrate the source of light.
LED headlights contain semiconductor chips which are by far the most important part of the whole unit. These are at the center of the light source. The chip has been divided into two. The divider of the chips is a junction. Each side of the chips has electric chargers.
One is populated with positive charges (p region) and the other is populated with negative charges (n region). Voltage is applied to the semi-conductor when the lights are switched on. The voltage provides the negative electrons with enough energy to cross the junction onto the p region.
There is a set threshold at which the electrons acquire enough energy to cross over the junction. Without hitting this threshold, the unit will not light. After crossing over to the p region, the n electrons are attracted to the positive charges and the two recombine and produce an electromagnetic energy which is in the form of photons of light.
The frequency of the photons (the color of light) will vary depending on the semi-conductor material used.
- Smaller in size providing better flexibility
- Instantly turn on with no warm up periods
- Energy sufficient
- Easy to install
- Costs more to produce
- Have a low amount of light generated
- High temperatures around the adjacent parts
In your search, you might come across individuals referring to these headlights as quartz halogen headlights or tungsten halogen lamps. These are the closest technology to incandescent lamps. The filament is made of ductile tungsten and is surrounded by a halogen gas at a very high pressure (between 7-8 ATM).
The glass bulb is made from a high silica glass, high quartz or an aluminosilicate. The bulb tends to be stronger than the standard glasses so that the can safely contain the pressure.
How They Work
The halogen headlamps feature a tungsten filament that is similar to the one in an incandescent lamp. However, the halogen lamp is much smaller and provides the same wattage and is filed with a halogen gas. The halogen gas is very important since it helps to stop the filament from blackening with time and also significantly slows down the thinning of the tungsten filament. The halogen gas as such increases the life of the unit significantly.
The filament, with the presence of the halogen gas can hit high temperatures safely which provides for more light. The bulb itself should be able to withstand the high temperatures (2500 degrees Celsius) in order to provide a bright light. The bulb therefore features a fused quartz bulb rather than a silica glass.
But even when the halogen bulbs have specific features that help to counteract the temperature, it is the temperature that exposes the units to inefficiency since a lot of energy is lost as heat.
A halogen is an element that readily provides negative ions. There are 5 halogens that are used on these units. These include chlorine, fluorine, iodine, astatine and bromine. They are used in different halogen bulbs which are applied in different industries since they provide different abilities. Car headlights however contain a combination of argon and nitrogen.
- Long lifespan
- Low costs
- Vary in dimensions and sizes
- A decent illumination
- Energy inefficient
- Light is harder to focus
- Extra precaution should be taken when conducting an installation
Many also refer to these as HID headlights. These contain a combination of rare metals and rare gases that are heated to generate a bright blue or white light. Xenon headlights are twice as bright as the traditional halogen bulbs.
How They Work
These replace filaments with a gas capsule. The light produced comes from closely spaced electrodes. The discharge is air tight and is sealed inside of the small quartz capsule which is tubular. These headlights however require ballast which works to regulate the voltage that has been supplied to the gas in the capsule. The light produced is greater than that produced by standard halogen bulbs, and also consumes less power.
In these headlights, the light is produced by passing current through metal vapors. The free electrons collide with the vapor atoms and are knocked off course momentarily. When they get back to the orbit, the displaced electron emits quantum radiation. The wavelength of the radiation varies and depends on the type of the metal vapor used in the tube.
When switched on, only 5% of light is produced at first and the unit requires about 15 seconds before they can get to their full potential.
Note that HID lights are divided into single and dual beam units. Dual beam units provide both high and low beams.
- Longer lifespan compared to halogen headlights
- Require less power to operate
- Provide better visibility for drivers
- With too much glare they may be distracting for oncoming traffic
- High production costs than halogens
- Contain possibly hazardous materials
Now that we have had a look at the three headlight technologies available, you might be wondering which one you should prefer of the three. Well, while many might go for LED lamps since they feature the latest technology, the answer to which you should pick is not as straight forward as you might think.
The answer depends on the need you want to meet. The different technologies perform best in different environments. So consider your use and environment first before making a final decision.