81% to 17% VLT Auto Tinting Timed Performance Windows
MCR Safety VL2 Photochromic Safety Glass provides the industrial worker with a single option for many lighted environments. This auto tinting performance technology shifts from clear to gray in 30 seconds and will migrate from gray to clear in 180 seconds. This will allow you to work in applications that move from indoor to outdoor settings or extreme light settings to low light settings by eliminating the need to remove your safety glass to see safely. Coated with MAX6® Anti-Fog protection for 6 times better fog resistance than standard anti-fog.
When transitioning from clear to gray
(5-second increments)
As you can see from the numbers below, it does not take long when transitioning from clear to gray:
- At 0 seconds, there is 84.8% VLT
- At 5 seconds, there is 48% VLT
- At 10 seconds, there is 28.5% VLT
- At 15 seconds, there is 20.5% VLT
- At 20 seconds, there is 18.4% VLT
- At 25 seconds, there is 16.8% VLT
- At 30 seconds, there is 15.8 % VLT
VLT, when a lens is at full gray, is more of a medium gray due to it not reaching a complete 13% VLT.
When transitioning from gray to clear
(10-second increments)
One thing stands out from the numbers below: it takes longer to reach clear going from a gray lens. Here are the VLT measurements as they transition:
- At 0 seconds, there is 14.4% VLT
- At 10 seconds, there is 20.3% VLT
- At 30 seconds, there is 33.7% VLT
- At 40 seconds, there is 39.6% VLT
- At 50 seconds, there is 44.7% VLT
- At 60 seconds, there is 48.9% VLT
- At 70 seconds, there is 53.5% VLT
- At 80 seconds, there is 57.1% VLT
- At 90 seconds, there is 60.1% VLT
- At 100 seconds, there is 62.7% VLT
- At 110 seconds, there is 64.9% VLT
- At 120 seconds, there is 66.8% VLT
- At 130 seconds, there is 68.4% VLT
- At 140 seconds, there is 69.8% VLT
- At 150 seconds, there is 71% VLT
- At 160 seconds, there is 72% VLT
- At 170 seconds, there is 72.8% VLT
- At 180 seconds, there is 73.5% VLT
To reach an 84.8% VLT clear lens, a lens will take a total of 5 minutes of transition time. So, anyone needing fast-acting clear glasses should maybe think twice about selecting a photochromic lens.
Photochromic lenses are temperature-dependent, which means transitional performance varies. So, it’s important to remember these two factors when thinking about transition time:
- Photochromic lens performance is affected by local hot temperatures and humidity, meaning the safety glass' lens will not be as dark.
- Photochromic lenses for glasses are more effective in colder temperatures, meaning the safety glass lens will get darker.