Glossary of Headlight Terms

Understanding all the headlight terms that are used can be difficult sometimes. Use this glossary as a guide as you seek the headlights that are right for your vehicle.


Altezza/Euro lights:


Altezza lights (also known as Euro lights, Lexus lights, crystal lights, or clear lights) are vehicle tail lamp clusters made up of one or more internal lamp units, covered with a clear (or tinted) acrylic cover made popular by Lexus. They have been included as standard equipment on Toyota Altezzas and Lexus IS300s since 1998. Altezza lights sometimes include LED bulbs. Altezza/Euro lights are popular customization products for modified cars but are now standard equipment on many other vehicles.




ASIC (application-specific integrated circuit) digital chip technology:

An integrated circuit (IC) customized for a particular use, rather than intended for general-purpose use.



hid ballastA ballast provides the starting voltage and ignition pulses necessary to ignite HID headlamps. It regulates the current flowing through a headlamp after the lamp has been started and stabilizes the power to the lamp while stabilizing the current and voltage fluctuations. If the bulb is powered from a constant voltage source such as directly from the AC wiring, the current will increase until the bulb destroys itself. Using a ballast maximizes lamp life and ensures other performance characteristics such as color and light output.



Bi-Xenon Bulbs:

On new cars, most HID headlights are only offered as a low-beam headlight with a halogen bulb for the high beam. Bi-Xenon headlights offer xenon light output for the low and high beams, and are housed in the same headlight projector. A Bi-Xenon kit converts both low beam and high beam to HID with one single bulb that shifts upward when is switched to high beam. This upward shift in the Bi-Xenon bulb creates a further light projection to increase visibility.


CANBUS or CAN (controller area network) bus:

A CAN (controller area network) bus (a communication system that transfers data between components inside a computer) or CANBUS is designed to allow microcontrollers and devices to communicate with each other in applications without a host computer. It was designed originally for automotive applications, but is also used in many other contexts. Modern automobiles may have as many as 70 electronic control units (ECU) for various subsystems.Some of these form independent subsystems, but communications among others are essential. The CAN standard was devised to fill this need.



hid-capacitors.jpgA capacitor is a piece of wiring between your HID ballast and your car's power source to help regulate the electrical system. Capacitors “smooth out” power demands by providing a short burst of energy when needed. When headlight voltage is too high, extra power is stored in the capacitor. When voltage drops, the capacitor discharges that stored power in order to keep the current flowing. Common issues a capacitor can resolve are light flickering (strobe effect) and "Bulb Out" indicator lights on your dash.



Color temperature:

Light color is measured on a temperature scale referred to as Kelvin(K). Lower Kelvin numbers mean the light appears more yellow; higher Kelvin numbers mean the light is whiter or bluer. The HID bulbs sold by HIDeXtra range in temperature from 3000K (deep golden yellow) to 10000K (deep blue).


Daytime Running Lights (DRLs):

Headlights that are used during the day rather than only at night. DRLs can help reduce or prevent collisions with other cars and pedestrians by making your car more visible, even in daylight. Four out of the top 10 insurers are so convinced of their safety advantage that they offer a discount for daytime running lights. Many automobile manufactures now include DRLs as standard equipment.


Fog lights:

hidextra-fog-light-kit.jpgFog lamps provide a wide, bar-shaped beam of light with a sharp cutoff at the top, and are generally aimed and mounted low.They were designed for low speed driving to increase the light directed towards the road surface in conditions of poor visibility due to rain, fog, dust or snow.





Halo projector lights:


A halo projector light is a kind of headlight that produces a smooth, solid beam or ring of uninterrupted light (unlike LEDs, that show individual lights).





Halogen bulb:

The halogen light bulb or lamp is a type of incandescent lamp which uses halogen gas in order to increase both light output and rated life. Most car manufacturers today include halogen bulbs as standard equipment on cars due to their moderately high efficiency, quality of light, low cost, and high rated life compared to regular incandescent lamps.


HID (high intensity discharge) or Xenon bulb:

HID bulbs in vehicles are enclosed transparent quartz tubes filled with a mix of gases, a tungsten electrode at each end, and a high-voltage electric current passing through to emit light when the gases get stimulated by the current. Despite alternately being called Xenon bulbs, HIDs actually use a metal-halide mix and rely on xenon gas only during start-up. A xenon bulb produces 3000 lumens, while a halogen light generates 1400 lumens, which is why HIDs are preferable to halogens for providing the most amount of light for the least amount of energy.


Hi/Lo Bulbs:

Also known as type 2 bulbs, Hi/Lo bulbs come with one primary bulb (xenon) and one secondary bulb (halogen). The xenon bulb is used for normal driving conditions and the halogen bulb is used as a high beam. A Hi/Lo kit converts the low beam to HID while high beam stays as halogen. For most vehicles the Hi/Lo HID kits are highly recommended since most car owners use only the low beams for everyday driving.


LED (light-emitting diode) bulb:

Instead of gas and filaments, LEDs rely on small diodes that produce light when electric current excites their electrons. They need an low amount of power to work but do produce a significant amount of heat on the diode. RAZIR LEDs are made with a cooling system at the bottom of the headlight to keep them from melting while protecting other car components. On the brightness scale, LEDs are brighter than halogen headlights while offering a warmer light than HIDs and providing much more focused rays. LEDs also last much longer, ranging up to 10,000+ hours.



A measure of the total amount of visible light emitted by a source. Lumens are the raw quantity of light energy given vs. the color temperature, which is measured by Kelvins.


Original Equipment Manufacturer (OEM):

An OEM is a term used when one company makes a part or subsystem that is used in another company's end product. An OEM may be a company that is a subcontractor or an authorized distributor of a vehicle manufacturer. An OEM part would be generally be a vehicle part that comes as standard equipment on a vehicle due to this arrangement.



A phrase used to describe devices that work as soon as they are connected. In electronic applications, the computer automatically recognizes the device, loads new drivers for the hardware if needed, and begins to work with the newly connected device. HIDeXtra’s conversion kits for both HID and LED lights feature plug-and-play technology.


Relay Harness:

hid-relay-harness.jpgWhile HID headlights don't draw as much power as standard halogen bulbs, they require a significant amount of voltage to ignite the lamp. If your stock wiring is still in place with your HID bulbs, sooner or later the wiring harness will likely burn out or cause flickering issues due to heat buildup. A relay harness will help regulate the power and keep the lights running smoothly and last longer.