In the beginning there were only the parabolic or parabol reflectors. Through the replacement with a diffuser, a free-form reflector was introduced and by adding a lens, the ellipsoid. If todays rear-lights are not directly equipped with LED-technology, then the apparent bundled perception is not created by many small light sources but by the shape of the respective reflectors.
It can however, be done completely without reflexion, which, as we all know, throws back almost the total amount of light. If we take, instead of a reflector, a translucent prism, we receive, depending on the angle, a portion of the refracted and reflected light. More is explained on the page about light. Thus, a rear light can manage without a reflector and having a very small depth.
Reflecting prisms as partial reflectors are also possible. Nowadays, one should not assume the prisms to be as large as they were when optics-tests were carried out at school. The mini-optics with prism sizes of around one millimeter, which are used in the cover-lenses, are sufficient. This is called 'diffusion optics', and is why we are so astonished by the sparkling brilliance of some rear lights.
The lines, which either as individual points of light or light strips, run through the whole headlamp combination, for a long time now deviate from a straight line. They now not only indicate the marque but also the various model-series. This new fashion begun with the introduction of daytime running lights and now, only when the headlamps are switched on, do they have difficulties carrying their message out into the world.
Thereby, we haven't even spoken about shape, colour and intensity. Earlier, the individual functions of the rear lights were built up either next to each other or concentrically. There the yellow-orange coloured indicators made up the core and the rest was arranged around them. Nowadays, this type of separation has pretty much been lifted.
The area for a certain
function can either be solid or the edge-lighting may be more emphasized. As far as size and shape are concerned, there are hardly any restrictions, inside of them, other functions are even possible. Through varying light intensity inside this area, this can even have spatial effect.
Previously, colour was given to the normal bulb-light through a coloured cover-lens. In the meantime, the light source can also be coloured and the cover-lens can be transparent. Either that or both together design the colour. In the meantime, also the colour of the rear lights when they're not burning is important. Should this not be white, then it should perhaps only be bi-coloured instead of tri-coloured. Indeed, at the end of the day, the designer has the last word. 07/12