As spring turns into summer and temperatures rise, many hidden dangers inside your vehicle can impact your daily life—especially for those who rely on glasses for vision. Here are four common scenarios where heat can harm your eyewear:

When parked under the sun, temperatures inside a car can exceed 50°C (122°F) even if it's just 32°C (90°F) outside. This extreme heat can deform resin lenses, cause anti-reflective coatings to peel, and impair visual clarity. Many resin lenses are made of multiple layers with different expansion rates. When the temperature reaches 60°C, the lens may become blurry or develop a mesh-like pattern. Avoid leaving these glasses in hot places such as saunas or cars in summer.

Frames made from plastic or acetate are shaped by heating and cooling processes. Prolonged exposure to high temperatures can soften and deform them. Frame deformation may cause:

1. Optical center misalignment, affecting vision clarity and causing dizziness or nausea.
2. Uneven weight distribution, leading to nose and ear pressure marks.
3. A distorted look that affects your personal image.

Reading glasses use convex lenses to focus light. If left in the car under direct sunlight, the focused light can generate high temperatures at the focal point—damaging interior surfaces, accelerating aging of materials, and in extreme cases, causing car fires. They work similarly to magnifying glasses, which should never be placed on dashboards under sunlight.

These lenses contain a thin polarizing film. If exposed to strong sunlight and heat over time, this film can become damaged—leading to a rippling or wave-like visual effect and the loss of polarization functionality.

In summer, the temperature inside a vehicle can rise rapidly. As an experienced driver, be mindful not to leave your glasses in the car. Protect your eyewear—and your safety—by taking them with you when you park.