10.8.2 Headlights
Figure 10.11 Example of head lighting lamp.
There are a huge number of different design solutions and types of headlights. On the one hand, the design was simplified, and on the other – it became more complicated and more expensive. But the essence of the device has always been to convert the light of the lamp 20-30 watts into a powerful light flux, which is sufficient to illuminate the roadway at a fairly large distance. For this purpose, reflectors of the special form that are capable to collect and direct a stream of light from a lamp in the necessary direction and with the required power are used. Options with the installation of a condenser lens are also possible.
Note
Probably everyone as a child burned various drawings on a wood with a help of magnifying glass. In order to do this, the temperature must be high enough, but this is not the point. The light, falling on the magnifying glass, is amplified many times (depending on the characteristics of the lens) and is focused at a certain distance. And in the case of the reflector inside the headlight: it has a curved surface, which resembles the surface of a normal lens. And in the center of this reflector there is a lamp.
Interesting
At this stage of technology development, reflectors can have a rather complex shape for the most efficient amplification and direction of lamp light.
Nowadays, halogen lamps or gas-discharge tubes of main and low beam are used in headlights.
Note
Headlights are designed for collecting and amplifying light from lamps for better road lighting.
It is also worth mentioning that now LED headlights with LEDs are becoming more common. This technology is quite expensive, thus at the moment it is used only on fairly expensive cars.
2 MB