EP4600727A2 — Optical filter comprising a variable transmittance layer

USPTO Abstract

A optical filter comprising a variable transmittance layer having a first spectrum in a dark state, and a second spectrum in a faded state; and a color balancing layer having a third spectrum; each of the first, second and third spectra comprising a visible portion; the first and third spectra combining to provide a dark state spectrum approximating a dark state target color; and the second and third spectra combining to provide a fades state spectrum approximating a faded state target colour. The optical filter may further comprise a light attenuating layer. The optical filter may further comprise part of a laminated glass.