Protecting the Adhesive from Sun Damage
Another key function of the frit is UV protection.
Sunlight contains ultraviolet (UV) rays, which can slowly break down the adhesive that holds the windshield in place. The black ceramic enamel absorbs these UV rays, preventing them from damaging the adhesive underneath.
This protection helps the windshield remain secure and durable for years.
Why the Dots Fade from Large to Small
Why the Dots Fade from Large to Small
You might notice that the black band near the edge gradually transitions into smaller dots as it moves toward the clear glass. This pattern is called a dot matrix, and it serves an important purpose.
The gradient helps distribute heat more evenly across the glass. Without it, the sudden transition between the black border and clear glass could create uneven heating when exposed to sunlight.
This could lead to:
Thermal stress
Glass distortion (called “lensing”)
Potential cracks
The dot pattern helps prevent these issues while keeping the windshield visually smooth.
Improving the Car’s Appearance
Besides functionality, the dots also improve the overall look of the windshield.
The gradient pattern creates a smooth visual transition between the black border and the transparent glass. It also hides the adhesive and small imperfections along the edges, giving the windshield a clean, finished appearance.
The “Third Visor” Behind the Rearview Mirror
In many vehicles, you’ll see a larger cluster of black dots behind the rearview mirror. This area is sometimes called the “third visor frit.”
Its purpose is to block sunlight that might otherwise pass through the gap between the driver and passenger sun visors. This helps reduce glare and improves driving comfort.
