Nano-particle based variable transmission devices

A method of varying the opacity of a variable transmission assembly comprising:

• providing a variable transmission assembly including a first light-transmissive electrode, a second light-transmissive electrode, and a variable transmission medium disposed between the first and second light-transmissive electrodes, wherein the variable transmission medium comprises zirconium dioxide nanoparticles, titanium dioxide nanoparticles, or zinc oxide nanoparticles dispersed in a fluid having a dielectric constant less than 10;
• and
• providing an electric current between the first and second light-transmissive electrodes and through the variable transmission medium.