Glasses are tinted using a heat treatment process. This process utilizes chemicals to permanently change the color of the lens.
The Tinting Process Explained
The primary method for tinting lenses, like those made from plastic CR-39 and polycarbonate, involves a heat treatment. This isn't simply about adding a coating; it's a chemical alteration at a molecular level.
Step-by-Step Breakdown
- Chemical Preparation: Specific chemicals are prepared that correspond to the desired tint color.
- Heat Application: The lens is placed in a controlled environment and heated to a precise temperature.
- Chemical Immersion/Exposure: The heated lens is then immersed in or exposed to the chosen chemical dye.
- Color Absorption: At this point, the lens material absorbs the color molecules.
- Cooling and Setting: The lens is then cooled, which causes the dye to bond permanently to the lens material.
Practical Implications
- Permanent Color: This method ensures that the tint is not simply a coating that can be easily scratched off.
- Consistent Color: The process allows for a very uniform and consistent color across the entire lens.
- Variety of Tints: This method can produce a wide variety of tints, from light shades to darker tones.
Lens Materials Commonly Tinted:
| Lens Material | Tinting Method |
|---|---|
| Plastic CR-39 | Heat treatment with chemicals |
| Polycarbonate lenses | Heat treatment with chemicals |
