system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do older cars have a kind of line pattern on the headlights and it is a little blurry while newer cars have nice and transparent headlights?
gpt
Normal driving light (not high beam and not parking lights) has to be asymmetrical, meaning the beam of light needs to light up the road differently. Towards the middle/traffic, the light has to hit the road sooner than towards the side. This is to not blind the oncoming traffic, yet provide enough light (and give you enough time) to react to pedestrians/bikes/animals that could be on the side of the road.

One could now think that the lightbulb towards the middle is just pointed lower than the one to towards the outside. But that's not the case. Both bulbs are shining on both sides. Asymmetrical.

On older cars, this effect was achieved by making lines and making the glass thinner and thicker different places, it creates this difference in where the light beam hits the road (if you know about the lights refraction in glass).

Today, this is done in a much more technical way, thus the lines are not needed anymore (also making it much cheaper to replace a broken headlight glass).