What’s the Difference Between Photochromic and Electro-Photochromic Sunglasses or Helmet Visors?

1. Photochromic Lenses

• These lenses automatically darken when exposed to sunlight (UV rays), and gradually return to clear in low light or indoors.

• The change is chemical, using molecules that react to UV exposure.

• There are no electronics involved — it’s a fully passive system.

• Transition time: 10–30 seconds to darken, and 1–2 minutes to return to clear.
  ⚠️ This delay can cause discomfort and reduced visibility, especially in fast-changing light conditions — potentially compromising safety.

• Typically used in everyday eyewear and standard sport sunglasses.

2. Electro-Photochromic Lenses (Like Skreenlock)

• These lenses use electro-photochromic technology, where a tiny electrical charge adjusts the tint level in real time.

• In many systems, this requires a button, app, or light sensor to manually or automatically trigger the change.

• Standard electro-photochromic glasses or visors are not waterproof and are prone to damage in wet or humid conditions — Skreenlock products, on the other hand, are fully waterproof and built for durability in all environments.
  🚫 NOT the case with Skreenlock — there are no batteries, no settings, and no user adjustments. Ever.

• ⚠️ Note on Electro-Photochromic Speed Some standard electro-photochromic lenses can actually be too fast, changing tint so rapidly that they may create stroboscopic effects, especially in environments with flickering or rapidly changing light — which can be disorienting or uncomfortable. ✅ Skreenlock avoids this entirely. It uses a smart chip-controlled film that is calibrated to match the natural reaction time of the human pupil, delivering a smooth, comfortable transition with no sudden jumps — just perfect visual comfort at every moment.

• The change is instantaneous and perfectly responsive to real-world lighting conditions.
  ✔️ With Skreenlock: never too clear, never too dark — always adapted to your environment.

• Traditional systems require a small power source.
  ⚡ Skreenlock uses a patented chip-powered film, so no battery is needed.

• Ideal for motorcycling, aviation, outdoor sports, and any environment with rapidly changing light.

Summary:

Feature	Photochromic	Electro-Photochromic Standard
Speed	Slow (30s–2 min)	Instant (<1 sec)	Instant
Power Source	None	Usually battery	None
Control	Automatic	Smart/manual	Fully automatic
Waterproof	Yes	No	Yes
Ideal For	Casual wear, slow transitions	Sports, high-speed conditions	Extreme sports, helmets, any regular activity