crystal lens technology (CLT)

crystal lens technology (CLT) is an auto-darkening filter technology developed by optrel for the brightest and most natural view possible. In the light state the filter has shade 2.0, so you see your surroundings almost as clearly as through an ordinary window.

How it works

At the heart of CLT is a specially developed coated lens. The coating optimises light transmission across a broad colour spectrum: colours are not distorted, and critical visual information becomes visible — such as the tarnish colours on a weld seam.

What you gain

Compared with standard filters, CLT gives you a brighter view in the light state, which makes preparation and post-weld work easier. You see the weld pool better, which matters especially in TIG welding, and clearly visible tarnish colours let you control the temperature and quality of the seam. A clearer view also means less eye strain over long welding cycles, fewer mistakes and less rework.

The technology pays off wherever precision counts: TIG and laser welding, precision cutting, stainless steel processing, machine and apparatus construction, and welder training, where better visual feedback shortens the learning curve.

Good to know

The outer surface of the filter is sensitive to scratches — clean it only with the microfibre cloth that optrel supplies with every product. In helmets with laser protection, the light state is 2.5 because of the additional coating. CLT is used in helix clt, panoramaxx clt, sphereX clt, crystal2.0 and panoramaxx hybrid clt.