SPECTRUM-MODULATED SMART WINDOWS

• US 20130128336A1
• Filed: 04/04/2011
• Published: 05/23/2013
• Est. Priority Date: 04/05/2010
• Status: Active Grant

• Current Assignee: University of Cincinnati
• Original Assignee: University of Cincinnati
• Inventors: Dean, Kenneth A., Heikenfeld, Jason Charles, Rudolph, John David
• Granted Patent: US 9,081,171 B2
• Time in Patent Office: Days
• US Class Current: 359/290
• CPC Class Codes: E06B 2009/2464 featuring transparency control by applying voltage, e.g. LCD, electrochromic panels
• CPC Class Codes: E06B 9/24 Screens or other constructions affording protection against light, especially against sunshine; Similar screens for privacy or appearance; Slat blindsoperating, guiding or securing devices or arrangements for roll-type closures E06B9/56; free-hanging flexible screens A47H23/00
• CPC Class Codes: G02B 26/00 Optical devices or arrangements for the control of light using movable or deformable optical elements control of light by modification of the optical properties of the media of the elements involved therein G02F1/00
• CPC Class Codes: G02B 26/004 based on a displacement or a deformation of a fluid
• CPC Class Codes: G02B 26/005 based on electrowetting
• CPC Class Codes: G02B 26/02 for controlling the intensity of light G02B26/004 takes precedence

Abstract

Methods, systems, devices and/or apparatuses are provided that selectively reflect the infrared spectrum independent of other regions of the solar spectrum in order to actively manage solar heat gain across surfaces such as windows, skylights, roofs, siding and the like.

Claims

1. A surface structure adapted to have a first selectable state that is transmissive to the solar spectrum, and a second selectable state that restricts transmission of at least a part of the solar spectrum, the surface structure comprising:

at least one layer comprising a hydrophobic surface and a fluid contacting at least a portion of the hydrophobic surface;

wherein a contact angle of the fluid on the hydrophobic surface is altered when a voltage signal is applied to the surface structure.

2. The surface structure of claim 1 wherein the contact angle of the fluid causes the fluid to change the fluid'"'"'s coverage area on the hydrophobic surface.

3. The surface structure of claim 1 wherein the fluid comprises a dispersed pigment.

4. The surface structure of claim 3 wherein the pigment comprises at least one of polystyrene, melamine, ethylene bis-melamine, acrylic, fluoropolymer, hollow styrene-acrylic spheres, polyimide, high density polyethylene, perylenes, quinacridones, dioxazines, titanium dioxide, and phthalocyanines.

5. The surface structure of claim 4 wherein the pigment comprises particles with a high refractive index incorporated in a low density host pigment material.

6. The surface-structure of claim 1 wherein the fluid is reflective in the infrared region of the solar spectrum, the voltage signal applied to the fluid modulates the infrared reflection by at least 30%.

7. The surface structure of claim 1 wherein the voltage signal is applied to the fluid at least one of directly and indirectly.

8. The surface structure of claim 1 wherein the voltage signal applied to the fluid modulates the visible transmission by at least 50%.

9. The surface structure of claim 1 wherein the surface structure comprises at least one of a window and a skylight.

10. The surface structure of claim 1 wherein the at least one layer is optically coupled to a substantially opaque structure comprising at least one of a wall material and a tile material.

11. A window adapted to have a first selectable state that transmits at least 50% of the visible spectrum, and a second selectable state that reflects at least a portion of the near infrared spectrum, the window comprising:

an exterior layer;

an electrofluidic layer operably coupled to the exterior layer, the electrofluidic layer adapted to selectively reflect at least a portion of infrared light; and

an interior layer.

12. The window of claim 11 further comprising channel electrodes in the electrofluidic layer such that a voltage applied to the channel electrodes changes the fluid contact angle with the channel, thereby moving the fluid into the channel and wherein the fluid determines, at least in part, a transmissive attribute of the electrofluidic layer.

13. The window of claim 11 wherein the window is further adapted to have a second selectable state that reflects at least a portion of a visible light spectrum.

14. The window of claim 11 wherein the window is further adapted to a second selectable state that absorbs at least a portion of a visible light spectrum.

15. The window of claim 11 wherein the second selectable state reflects at least about 25% of the infrared light.

16. The window of claim 11 wherein the first selectable state has haze below about 20%.

17. The window of claim 11 wherein the window is a component in a system comprising at least one additional component of an interior climate sensor monitoring an interior climate near an interior surface of the window, an exterior climate sensor monitoring an exterior climate near an exterior surface of the window, a timing circuit, and a microprocessor programmed with climate control algorithms, with said at least one additional component providing a controlling signal for selecting one of the selectable states.

18. The window of claim 11 further comprising a second electrofluidic layer operably coupled to the interior layer.

19. The window of claim 11 wherein the fluid comprises a pigmented fluid.

20. A window adapted to have a first selectable state that transmits at least about 50% of the visible and infrared solar spectrum, and a second selectable state that transmits less than about 10% of the visible spectrum and more than about 50% of the solar infrared spectrum, the window comprising:

an exterior layer;

an electrofluidic layer operably coupled to the exterior layer, the electrofluidic layer adapted to transmit at least a portion of Infrared light; and

an interior layer.

21. The window of claim 20 wherein the first selectable state has haze less than about 20%.