The wonderful world of photochromic lenses: Why do they change with light?

In the sunny outdoors, the photochromic will quickly darken, just like sunglasses, blocking strong ultraviolet rays for the eyes; and once we return to the room, the lenses will quietly return to transparency, without affecting normal vision. This magical photochromic lens, like a life, freely adjusts its color according to the changes in light. What secrets does it hide?

Types and characteristics of photochromic lenses

MASS
The photochromic substance (silver halide particles) is evenly distributed in the lens substrate material, the color change effect is stable and lasting, and the color change is more natural.

SPIN/DIPPING
The photochromic substance is attached to the film layer on the surface of the lens, and can be coated on the existing ordinary lenses to achieve the color change function. The color change speed of the film photochromic lens may be slightly faster than that of the substrate photochromic lens.

How to choose high-quality photochromic lenses

COLOR CHANGE SPEED
High-quality photochromic lenses should have a fast color change response capability. It can quickly darken in the sun, generally reaching a darker color state within tens of seconds, providing timely protection for the eyes; after returning to the room, it can quickly return to transparency within a few minutes, without affecting normal visual clarity

FADING STABLILITY

After multiple cycles of discoloration and fading, the discoloration performance of the lens will not show obvious decline. Some poor quality photochromic lenses will have problems such as incomplete fading and color residue after using for a period of time, affecting the visual effect and aesthetics.

Our Ideal Optical has recently launched Fast Change lenses. In the lens transmittance test, this variety has a visible light transmittance of 18.994% after 15 minutes of irradiation in the same test environment, which is lower than most other photochromic lenses, which means that the degree of discoloration is deep; at the same time, it is calculated that the half-recovery time point of this variety is 116 seconds, that is, the lens fades to a half-recovery state 116 seconds after the end of irradiation. Therefore, we call it Fast Change, not only Fast, but also very deep.

It instantly turns into dark in the sun and becomes transparent in the shade, like a smart bodyguard for the eyes; one mirror with two sides, magically adapts to the light, making the world always clear and comfortable!