03 — The light
Screens are tuned for noon.
Artificial light after dark carries the short wavelengths of the middle of the day. The lens takes most of them out.
Cut-off
480
- < 1 % passes
- mostly absorbed
- partial
- nearly clear
What it removes
Visible light runs from roughly 380 to 700 nanometres. The short end reads as violet and blue.
Around 62 % of the light the eye is most sensitive to still arrives. The room stays legible. The colour shift is warm and noticeable.
Measured
- ≈ 480 nm
- < 1 % passes
- ~ 62 %
- warm, noticeable
The lens
The glass is the product. The curve is the pitch.
The transmission curve is measured on the finished lens: steep at the short end, nearly clear above 500 nm.
Put them on after dark and the difference arrives in the first second — the room goes amber, the screen goes quiet.
