Glazing design with variable heat and light transmittance properties, device and method

摘要

An energy efficient optical window has different optical properties when irradiated by solar light from front or back side of the window. The window is used to reflect most of the infrared light at summer times, leaving the interior cooler and to absorb most of the infrared light at winter times, making the interior hotter by heat transfer from the hot window pane. Mechanical reversal of the window, inside out, is used to apply the needed version for winter and summer. The window is coated with alternating thin metallic and dielectric layers that transmit most of the visible light while reflecting most of the infrared part of the spectrum when impinged by solar light on one side and transmit most of the visible light while absorbing most of the infrared part of the spectrum when impinged by solar light on the other side.

主权项

1. An energy efficient optical window having different optical properties when irradiated by solar light from opposite sides, said window comprising:
a first side and a second side opposite the first side, wherein the window is movable between a winter position wherein the solar light impinges on the first side and a summer position wherein the solar light impinges on the second side; and an infrared absorbing layer and an infrared reflecting layer adjoining each other and having a high transparency for visible light, said absorbing layer absorbing at least about 40 percent of impinging near infrared light, and said infrared reflecting layer reflecting at least about 80 percent of impinging near infrared light.