Majority of car manufacturers have started to realize the popularity of Xenon HID lights and incorporated them as a standard equipment in their high level cars. You'll also have the option of installing these HID headlights on your mid-range cars. These products are also sold separately by a large number of offline and online stores. Owners of older cars are very curious to know about this lighting option and its vitality as a source of illumination for their cars.
Xenon HID lights provide brighter illumination in comparison to halogen and are more energy and cost-efficient as well. But when it comes to glare, the federal requirements are similar for both. Some people raise the question why Xenon headlights look blue. The reason lies in the distribution of energy generated inside the bulb by a number of noble gases, specifically including xenon, that are under tremendous pressure. The bulb contains a line spectrum in its output emission with some of its tops in the noticeable blue area. Here, all the lights generated by these headlights are not blue, but they still appear to be blue in color.
Some manufactures attempt to replicate a Xenon HID bulb by coating or painting a halogen bulb blue. But, the actual truth is a genuine Xenon HID system is not blue in color. You only Observe a bluish color because of the resultant high voltage arc and the release of the Xenon gas inside the bulb. So, beware of counterfeited Xenon headlights in the market.
When you compare a halogen headlight with a Xenon headlight, you can clearly distinguish a number of factors. Firstly, you'll get a glittering bluish white illumination through a Xenon light, where a halogen bulb emits yellowish light. Secondly, the Xenon system covers a wider area and generates more light than a halogen system. It is also very easy to identify Xenon HID systems as they have D2S, D2R, D1S, or D1R stamped on the external lens of their systems. The absence of any one of these combinations gives you a clear-cut idea that you do not possess a true Xenon HID system.
If you want to verify whether these lights are legally approved or not, you can look for the letters "DOT" pointed on your Xenon HID system. In the USA, you can use only those headlights on public roads which are DOT approved.