US 12,392,967 B2
Multicoated tunable optical devices
Gleb M. Akselrod, Kenmore, WA (US); Lie “Larry” Zhao, Washougal, WA (US); Erik Edward Josberger, Renton, WA (US); and Prasad Padmanabha Iyer, Albuquerque, NM (US)
Assigned to Lumotive, Inc., Redmond, WA (US)
Filed by Lumotive, Inc., Redmond, WA (US)
Filed on Apr. 24, 2023, as Appl. No. 18/305,572.
Prior Publication US 2024/0353624 A1, Oct. 24, 2024
Int. Cl. G02B 6/293 (2006.01); G02B 1/115 (2015.01); G02B 26/00 (2006.01)
CPC G02B 6/29395 (2013.01) [G02B 1/115 (2013.01); G02B 26/001 (2013.01)] 31 Claims
OG exemplary drawing
 
1. A tunable optical device, comprising:
a dielectric substrate;
an array of multicoated metal elements extending from the dielectric substrate and spaced from one another by less than a wavelength of an operational bandwidth to form subwavelength gaps between adjacent multicoated metal elements, wherein each multicoated metal element comprises:
a metal core having a base wall, opposing sidewalls, and a top wall;
a first, optically reflective metal coating deposited on at least one of (i) the top wall and (ii) the sidewalls; and
a second, passivation coating deposited on the sidewalls and the top wall;
a conductive barrier material positioned between the base wall of each metal element and the dielectric substrate; and
a tunable dielectric material that has a tunable refractive index positioned within the gaps between adjacent multicoated metal elements.