How to Clean a Flashlight Lens

Here are the steps I follow to clean the glass lenses on my flashlights.

Materials

You should be able to find these materials in a drugstore or supermarket.

• Lens cleaning spray.

This is the same stuff you use to clean eyeglasses. Make sure it is "safe" for coated lenses.

• Lens cloth.

These are the small cloths which come with eyeglasses or professional optics.

Steps

• Run the lens under water to remove any grains of sand.

Grains of sand or other unseen particles can scratch the lens during cleaning. It is important to remove these particles first.

• Spray lens cleaner on the lens.

I hold my flashlight with the lens facing up. And I spray the lens so that the fluid is trapped on top.

• Rub the lens to remove dirt.

I simply use my finger to agitate the cleaning fluid on the lens.

• Rinse the lens in running water.

This removes the cleaning fluid and dirt.

• Dry the lens with the lens cloth.

Wipe the lens with a clean, dry lens cloth. This prevents water spots.

Preventing Damage

If your flashlight is not waterproof or if you're unsure, then you might have to find a different way to maintain your flashlight. For abrasive particles stuck to the lens, you can try blowing them off with compressed air. For rinsing, you can use a second, moist lens cloth to remove any soap and then dry with a separate clean, dry cloth. Whatever you do, don't allow water inside your flashlight.

Avoid harsh chemicals. Some soaps and glass cleaners will destroy the coating on your lens. Instead, use lens cleaning fluid to clean your lens.

Avoid abrasive fabrics. Paper towels and napkins contain small wood fibers which will scratch your lens over time. Also, don't use cotton swabs or wipe your lens with clothing. Instead, use a clean finger to clean the lens. And, use a lens cloth to dry your lens.

Don't run a hot flashlight under cold water, or the reverse; don't run a cold flashlight under warm water. The temperature difference can cause the lens to crack. Instead, wait until the flashlight reaches room temperature before cleaning it.

Tips

If the flashlight lens comes out dirty after drying it then try cleaning and drying the lens cloth. I use dish soap and clean water to handwash my cloth as needed. Make sure the cloth is dry before using it.

I prefer a lens cloth where each side is a different color or has some other distinguishing mark. The reason is, I prefer to always hold the cloth on the same side to prevent oil from getting on both sides. This way, I can use the lens cloth for longer periods before I have to wash it.

I prefer to buy the 8oz bottles of cleaning fluid which are a better value.

As long as the lens cleaner is "safe" on coated lenses, it is not necessary to buy a special formula to prevent streaks. When using my method, streaks should be cleared by the final rinse and dry.

Created: Monday, May 20, 2024

Updated: Monday, May 20, 2024