> Adjustable transmissivity glass is a reality but not yet practical enough for it to be ubiquitous.
Asimov says windows "will be polarized to block out the harsh sunlight." That sure sounds to me like putting LCD tech in a window, sans backlight and Bayer filter. We don't use the tech architecturally, but we certainly mass-produce it at the sizes needed for use as window panes. And passive photochromic lenses are also commodity items. Either one is completely practical for integration into a window, there just isn't currently demand to do so.
Asimov says windows "will be polarized to block out the harsh sunlight." That sure sounds to me like putting LCD tech in a window, sans backlight and Bayer filter. We don't use the tech architecturally, but we certainly mass-produce it at the sizes needed for use as window panes. And passive photochromic lenses are also commodity items. Either one is completely practical for integration into a window, there just isn't currently demand to do so.