Without these dots, the glass could become loose and eventually fall out of the frame. These frits are also there for aesthetic purposes.
I thought the transition from pure black to window with dots was made for thermic reasons, so there is not a hard line between hot and cold glass, and with that less stress on the material.
The complete black border is probably for holding it to the glue, I suspect.
“Without these dots, the glass could become loose and eventually fall out of the frame."
How?
As they write in the article:
the windshield glass in modern cars is bonded to its frame using a strong and long-lasting urethane adhesive.
“This makes the windshield a structural component of the vehicle’s body,” explained Reina. “The frit is black painted enamel that’s baked onto the surface of the glass, and it provides a secure point of contact between the glass, urethane adhesive, and windshield frame.”
I also quoted the article. I understand that part and the black stripe, but I don’t understand how the dots help in this.
The dots themselves don’t do anything, but the black border does. But if you see the dots coming off the glass, it’s a sign that the frit around the edge may also have started detaching from the glass.
Afaik the dots are just an aesthetic choice, the black border is functional.
Source: my old oem one had no dots, my new one does, tech said as much
