Electro-optical glazing structures having bi-directional control of electromagnetic radiation during total-reflection, semi-transparent and totally-transparent modes of operation

• US 6,583,827 B2
• Filed: 07/15/1999
• Issued: 06/24/2003
• Est. Priority Date: 11/27/1991
• Status: Expired due to Fees

• Current Assignee: Reveo, Inc.
• Original Assignee: Reveo, Inc.
• Inventors: Faris, Sadeg M., Li, Le
• Primary Examiner(s): Chowdhury, Tarifur R.
• Application Number:
  US09/354,192
• Publication Number:
  US 20020041346A1
• Time in Patent Office: 1,440 Days
• Field of Search: 349/16, 349/176, 349/13, 349/14, 349/15, 349/114
• US Class Current: 349/16
• CPC Class Codes: B82Y 15/00 Nanotechnology for interacting, sensing or actuating, e.g. quantum dots as markers in protein assays or molecular motors
• CPC Class Codes: C09B 67/0098 Organic pigments exhibiting interference colours, e.g. nacrous pigments
• CPC Class Codes: C09D 11/037 characterised by the pigment
• CPC Class Codes: C09D 11/17 characterised by colouring agents
• CPC Class Codes: C09K 19/00 Liquid crystal materials
• CPC Class Codes: C09K 19/52 characterised by components which are not liquid crystals, e.g. additives with special physical aspect: solvents, solid particles
• 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: F24S 50/80 for controlling collection or absorption of solar radiation
• CPC Class Codes: G01D 11/28 Structurally-combined illuminating devices
• CPC Class Codes: G02B 27/0093 with means for monitoring data relating to the user, e.g. head-tracking, eye-tracking
• CPC Class Codes: G02B 5/3016 involving passive liquid crystal elements optical properties of liquid crystals G02F1/0063; polarising elements associated with active liquid crystal devices G02F1/133528
• CPC Class Codes: G02F 1/1334 based on polymer dispersed liquid crystals, e.g. microencapsulated liquid crystals
• CPC Class Codes: G02F 1/133514 Colour filters
• CPC Class Codes: G02F 1/133536 Reflective polarizers G02F1/13362 takes precedence
• CPC Class Codes: G02F 1/133543 Cholesteric polarisers
• CPC Class Codes: G02F 1/13362 providing polarized light, e.g. by converting a polarisation component into another one
• CPC Class Codes: G02F 1/133621 providing coloured light G02F1/133617, G02F1/133533 take precedence
• CPC Class Codes: G02F 1/133623 Inclined coloured light beams
• CPC Class Codes: G02F 1/13471 in which all the liquid crystal cells or layers remain transparent, e.g. FLC, ECB, DAP, HAN, TN, STN, SBE-LC cells G02F1/13475 takes precedence
• CPC Class Codes: G02F 1/13718 : based on a change of the texture state of a cholesteric liquid crystal
• CPC Class Codes: G02F 1/1393 : the birefringence of the liquid crystal being electrically controlled, e.g. ECB-, DAP-, HAN-, PI-LC cells G02F1/1396, G02F1/141 take precedence
• CPC Class Codes: H04N 2213/008 : Aspects relating to glasses for viewing stereoscopic images
• CPC Class Codes: Y02B 10/20 : Solar thermal
• CPC Class Codes: Y02E 10/40 : Solar thermal energy, e.g. solar towers

Abstract

Electro-optical glazing structures having bi-directional control of electromagnetic radiation during total-reflection, semi-transparent and totally-transparent modes of operation which are electrically-switchable for use in dynamically controlling electromagnetic radiation flow in diverse applications.

Claims

1. An electro-optical glazing structure comprising:

an electro-optical panel controlling, within a characteristic reflection bandwidth, reflection and transmission of electromagnetic radiation that is incident on a first outer surface of the electro-optical panel and that is incident on a second outer surface of the electro-optical panel, said electro-optical panel having an electrically-switchable reflective mode of operation and an electrically-switchable transmissive mode of operation,

wherein, in said electrically-switchable reflective mode of operation, said electromagnetic radiation having a first polarization state that is incident on said first outer surface is substantially reflected without absorption, said electromagnetic radiation having a second polarization state opposite said first polarization state that is incident on said first outer surface is substantially reflected without absorption, said electromagnetic radiation having said first polarization state that is incident on said second outer surface is substantially reflected without absorption, and said electromagnetic radiation having said second polarization state that is incident on said second outer surface is substantially reflected without absorption, and

wherein, in said electrically-switchable transmissive mode of operation, portions of said electromagnetic radiation that is incident on said first outer surface is substantially transmitted without absorption through said electro-optical panel, and portions of said electromagnetic radiation that is incident on said second outer surface is substantially transmitted without absorption through said electro-optical panel; and

an optical state switching mechanism for electrically switching said electro-optical panel into said electrically-switchable reflective mode of operation and said electrically-switchable transmissive mode of operation.

2. The electro-optical glazing structure of claim 1, which further comprises:

a window frame for mounting said electro-optical panel within a house or office building, or aboard a transportation vehicle.

3. The electro-optical glazing structure of claim 2, which further comprises:

a electromagnetic-sensor mounted on said window frame, for sensing electromagnetic conditions;

a battery supply mounted within said window frame, for providing electrical power;

an electromagnetic-powered battery recharger mounted within said window frame, for recharging the battery;

electrical circuitry mounted within said window frame, for producing glazing control voltages for switching into said electrically-switchable reflective and electrically-switchable transmissive modes of operation; and

a programmable micro-computer chip mounted within said window frame, for controlling the operation of said battery recharger and said electrical circuitry, and the production of said glazing control voltages as required by a radiation flow control program stored within said programmable microcontroller.

4. An intelligent window system for dynamic electromagnetic radiation control which comprises:

a plurality of said electro-optical glazing structures of claim 2, each mounted within a house or office building, or aboard a transportation vehicle; and

a central control computer for coordinating the operation of said electro-optical glazing structures.

5. An composite electro-optical glazing structure which comprises:

a plurality of said electro-optical glazing structures of claim 1, stacked together as a composite electro-optical structure,

wherein said composite electro-optical structure has more than two said optical states of operation which permit complex levels of electromagnetic radiation control.

6. The electro-optical glazing structure of claim 1, wherein said electro-optical panel comprises an electrically-active π

-phase retardation panel disposed between first and second electrically-passive cholesteric liquid crystal (CLC) electromagnetic radiation polarizing panels.

7. The electro-optical glazing structure of claim 6,

wherein said electrically-active π

-phase retardation panel and said first and second electrically-passive CLC electromagnetic radiation polarizing panels operate in said electrically-switchable reflective mode of operation to substantially reflect without absorption said electromagnetic radiation having a first circularly polarized state that is incident on an outer surface of the first electrically-passive CLC electromagnetic radiation polarizing panel, substantially reflect without absorption said electromagnetic radiation having a second circularly polarized state that is incident on said outer surface of the first electrically-passive CLC electromagnetic radiation polarizing panel, substantially reflect without absorption said electromagnetic radiation having said first circularly polarized state that is incident on an outer surface of the second electrically-passive CLC electromagnetic radiation polarizing panel, and substantially reflect without absorption said electromagnetic radiation having said second circularly polarized state that is incident on said outer surface of the second electrically-passive CLC electromagnetic radiation polarizing panel; and

wherein said electrically-active π

-phase retardation panel and said first and second electrically-passive CLC electromagnetic radiation polarizing panels operate in said electrically-switchable transmissive mode of operation to substantially transmit without absorption through the electro-optical panel said electromagnetic radiation that is incident on said outer surface of the first electrically-passive CLC electromagnetic radiation polarizing panel and has one of said first circularly polarized state and said second circularly polarized state, and substantially transmit without absorption through the electro-optical panel said electromagnetic radiation that is incident on said outer surface of the second electrically-passive CLC electromagnetic radiation polarizing panel and has one of said first circularly polarized state and said second circularly polarized state.

8. The electro-optical glazing structure of claim 6,

wherein said electrically-active π

-phase retardation panel and said first and second electrically-passive CLC electromagnetic radiation polarizing panels operate in said electrically-switchable reflective mode of operation to substantially reflect without absorption said electromagnetic radiation having a first linear polarized state that is incident on an outer surface of the first electrically-passive CLC electromagnetic radiation polarizing panel, substantially reflect without absorption said electromagnetic radiation having a second linear polarized state that is incident on said outer surface of the first electrically-passive CLC electromagnetic radiation polarizing panel, substantially reflect without absorption said electromagnetic radiation having said first linear polarized state that is incident on an outer surface of the second electrically-passive CLC electromagnetic radiation polarizing panel, and substantially reflect without absorption said electromagnetic radiation having said second linear polarized state that is incident on said outer surface of the second electrically-passive CLC electromagnetic radiation polarizing panel; and

wherein said electrically-active it-phase retardation panel and said first and second electrically-passive CLC electromagnetic radiation polarizing panels operate in said electrically-switchable transmissive mode of operation to substantially transmit without absorption through the electro-optical panel said electromagnetic radiation having one of said first linear polarized state and said second linear polarized state that is incident on said outer surface of the first electrically-passive CLC electromagnetic radiation polarizing panel, and substantially transmit without absorption through the electro-optical panel said electromagnetic radiation having one of said first linear polarized state and said second linear polarized state that is incident on said outer surface of the second electrically-passive CLC electromagnetic radiation polarizing panel.

9. The electro-optical glazing structure of claim 1, wherein said electro-optical panel comprises an electrically-passive π

-phase retardation panel disposed between first and second electrically-active cholesteric liquid crystal (CLC) electromagnetic radiation polarizing panels.

10. The electro-optical glazing structure of claim 9,

wherein said electrically-passive π

-phase retardation panel and said first and second electrically-active CLC electromagnetic radiation polarizing panels operate in said electrically-switchable reflective mode of operation to substantially reflect without absorption said electromagnetic radiation having a first circularly polarized state that is incident on an outer surface of the first electrically-active CLC electromagnetic radiation polarizing panel, substantially reflect without absorption said electromagnetic radiation having a second circularly polarized state that is incident on said outer surface of the first electrically-active CLC electromagnetic radiation polarizing panel, substantially reflect without absorption said electromagnetic radiation having said first circularly polarized state that is incident on an outer surface of the second electrically-active CLC electromagnetic radiation polarizing panel, and substantially reflect without absorption said electromagnetic radiation having said second circularly polarized state that is incident on said outer surface of the second electrically-active CLC electromagnetic radiation polarizing panel; and

wherein said electrically-passive π

-phase retardation panel and said first and second electrically-active CLC electromagnetic radiation polarizing panels operate in said electrically-switchable transmissive mode of operation to substantially transmit without absorption through the electro-optical panel said electromagnetic radiation having said first circularly polarized state that is incident on said outer surface of the first electrically-active CLC electromagnetic radiation polarizing panel, substantially transmit without absorption through the electro-optical panel said electromagnetic radiation having said second circularly polarized state that is incident on said outer surface of the first electrically-active CLC electromagnetic radiation polarizing panel, substantially transmit without absorption through the electro-optical panel said electromagnetic radiation having said first circularly polarized state that is incident on said outer surface of the second electrically-active CLC electromagnetic radiation polarizing panel, and substantially transmit without absorption through the electro-optical panel said electromagnetic radiation having said second circularly polarized state that is incident on said outer surface of the second electrically-active CLC electromagnetic radiation polarizing panel.

11. The electro-optical glazing structure of claim 1, wherein said electro-optical panel comprises first and second electrically-active cholesteric liquid crystal (CLC) electromagnetic radiation polarizing panels.

12. The electro-optical glazing structure of claim 11,

wherein said first and second electrically-active CLC electromagnetic radiation polarizing panels operate in said electrically-switchable reflective mode of operation to substantially reflect without absorption said electromagnetic radiation having a first circularly polarized state that is incident on an outer surface of the first electrically-active CLC electromagnetic radiation polarizing panel, substantially reflect without absorption said electromagnetic radiation having a second circularly polarized state that is incident on said outer surface of the first electrically-active CLC electromagnetic radiation polarizing panel, substantially reflect without absorption said electromagnetic radiation having said first circularly polarized state that is incident on an outer surface of the second electrically-active CLC electromagnetic radiation polarizing panel, and substantially reflect without absorption said electromagnetic radiation having said second circularly polarized state that is incident on said outer surface of the second electrically-active CLC electromagnetic radiation polarizing panel;

and

wherein said first and second electrically-active CLC electromagnetic radiation polarizing panels operate in said electrically-switchable transmissive mode of operation to substantially transmit without absorption through the electro-optical panel electromagnetic radiation that is within a characteristic transmission bandwidth and has said first circularly polarized state and that is incident on said outer surface of the first electrically-active CLC electromagnetic radiation polarizing panel, substantially transmit without absorption through the electro-optical panel electromagnetic radiation that is within said characteristic transmission bandwidth and has said second circularly polarized state and that is incident on said outer surface of the first electrically-active CLC electromagnetic radiation polarizing panel, substantially transmit without absorption through the electro-optical panel electromagnetic radiation that is within said characteristic transmission bandwidth and has said first circularly polarized state and that is incident on said outer surface of the second electrically-active CLC electromagnetic radiation polarizing panel, and substantially transmit without absorption through the electro-optical panel electromagnetic radiation that is within said characteristic transmission bandwidth and has said second circularly polarized state and that is incident on said outer surface of the second electrically-active CLC electromagnetic radiation polarizing panel.

13. The electro-optical glazing structure of claim 12,

wherein said first electrically-active CLC electromagnetic radiation polarizing panel operates in said electrically-switchable reflective mode to substantially reflect without absorption incident electromagnetic radiation within said characteristic reflection bandwidth having said first circularly polarized state and to substantially transmit without absorption incident electromagnetic radiation within said characteristic reflection bandwidth having said second circularly polarized state;

and

wherein said second electrically-active CLC electromagnetic radiation polarizing panel operates in said electrically-switchable reflective mode to substantially reflect without absorption incident electromagnetic radiation within said characteristic reflection bandwidth having said second circularly polarized state and to substantially transmit without absorption incident electromagnetic radiation within said characteristic reflection bandwidth having said first circularly polarized state.

14. The electro-optical glazing structure of claim 12, wherein said first and second electrically-active CLC electromagnetic radiation polarizing panels operate in said electrically-switchable reflective mode to substantially transmit without absorption incident electromagnetic radiation outside said characteristic reflection bandwidth.

15. The electro-optical glazing structure of claim 12, wherein said first and second electrically-active CLC electromagnetic radiation polarizing panels operate in said electrically-switchable transmissive mode to transmit more than 50% of incident electromagnetic radiation within said characteristic transmission bandwidth having either said first circularly polarized state or said second first circularly polarized state.

16. The electro-optical glazing structure of claim 1, wherein said characteristic reflection bandwidth comprises a portion of the visible light electromagnetic spectrum.

17. The electro-optical glazing structure of claim 1, wherein said characteristic reflection bandwidth comprises a portion of the UV light electromagnetic spectrum.

18. The electro-optical glazing structure of claim 1, wherein said characteristic reflection bandwidth comprises a portion of the JR light electromagnetic spectrum.

19. The electro-optical glazing structure of claim 1, wherein said electro-optical panel comprises an electrically-active it-phase retardation panel interposed between a pair of electrically-passive electromagnetic radiation polarizing panels each capable of reflecting electromagnetic radiation of a certain polarization state, whereby a totally reflective state of operation and a semi-transparent state of operation are provided over a region of the electromagnetic spectrum.

20. The electro-optical glazing structure of claim 1, wherein said electro-optical panel comprises an electrically-active it-phase retardation panel interposed between a pair of electrically-passive electromagnetic radiation polarizing panels each capable of reflecting electromagnetic radiation of a linear polarization state, whereby a totally reflective state of operation and a semi-transparent state of operation are provided over a region of the electromagnetic spectrum.

21. The electro-optical glazing structure of claim 1, wherein said electro-optical panel comprises an electrically-active π

-phase retardation panel interposed between a pair of electrically-passive electromagnetic radiation polarizing panels capable of reflecting electromagnetic radiation of linear polarization states that are parallel to one another, whereby a totally reflective state of operation and a semi-transparent state of operation are provided over a region of the electromagnetic spectrum.

22. The electro-optical glazing structure of claim 1, wherein said electro-optical panel comprises an electrically-active π

-phase retardation panel interposed between a pair of electrically-passive electromagnetic radiation polarizing panels capable of reflecting electromagnetic radiation of linear polarization states that are perpendicular to one another, whereby a totally reflective state of operation and a semi-transparent state of operation are provided over a region of the electromagnetic spectrum.

23. The electro-optical glazing structure of claim 1, wherein said electro-optical panel comprises an electrically-active π

-phase retardation panel interposed between a pair of electrically-passive cholesteric liquid crystal (CLC) electromagnetic radiation polarizing panels each capable of reflecting electromagnetic radiation of an LHCP state, whereby a totally reflective state of operation and a semi-transparent state of operation are provided over a region of the electromagnetic spectrum.

24. The electro-optical glazing structure of claim 1, wherein said electro-optical panel comprises an electrically-active π

-phase retardation panel interposed between a pair of electrically-passive CLC electromagnetic radiation polarizing panels each capable of reflecting electromagnetic radiation of a RHCP state, whereby a totally reflective state of operation and a semi-transparent state of operation are provided over a region of the electromagnetic spectrum.

25. The electro-optical glazing structure of claim 1, wherein said electro-optical panel comprises an electrically-active it-phase retardation panel interposed between a pair of electrically-passive CLC electromagnetic radiation polarizing panels, one of which is capable of reflecting electromagnetic radiation of the LHCP state and the other of which is capable of reflecting electromagnetic radiation of the RHCP state, whereby a totally reflective state of operation and a semi-transparent state of operation are provided over a region of the electromagnetic spectrum.

26. The electro-optical glazing structure of claim 1, wherein said electro-optical panel comprises an electrically-passive it-phase retardation panel interposed between a pair of electrically-active CLC electromagnetic radiation polarizing panels each capable of reflecting electromagnetic radiation of the LHCP state, whereby a totally reflective state of operation and a totally transparent state of operation are provided over a region of the electromagnetic spectrum.

27. The electro-optical glazing structure of claim 1, wherein said electro-optical panel comprises an electrically-passive π

-phase retardation panel interposed between a pair of electrically-active CLC electromagnetic radiation polarizing panels, both of which are capable of reflecting electromagnetic radiation of the RHCP state, whereby a totally reflective state of operation and a semi-transparent state of operation are provided over a region of the electromagnetic spectrum.

28. The electro-optical glazing structure of claim 1, wherein said electro-optical panel comprises a pair of electrically-active CLC electromagnetic radiation polarizing panels, one of which is capable of reflecting electromagnetic radiation of the LHCP state and the other of which is capable of reflecting electromagnetic radiation of the RHCP state, whereby a totally reflective state of operation and a totally transparent state of operation are provided over a region of the electromagnetic spectrum.

29. An actively-controlled window or viewing panel constructed from the electro-optical glazing structure of claim 1, wherein the transmission of electromagnetic radiation can be dynamically controlled over a region of the electromagnetic spectrum, between 50% transmission to 100% reflection and between 100% transmission to 100% reflection.

30. An actively-controlled window or viewing panel constructed from the electro-optical glazing structure of claim 1, wherein the transmission of electromagnetic radiation over the UV and IR regions of the electromagnetic spectrum can be totally reflected, rather than absorbed, reducing the temperature cycle range which the window structure is required to undergo.

31. An actively-controlled window or viewing panel constructed from the electro-optical glazing structure of claim 1, wherein only UV and IR radiation is reflected at the window surface, while electromagnetic radiation over the visible band is transmitted to the interior environment being maintained under thermal control.

32. An intelligent window system for installation within a house or office building, or aboard a transportation vehicle such as an airplane or automobile, wherein the electro-optical glazing structure of claim 1 is supported within a prefabricated window frame, within which are mounted:

a electromagnetic-sensor for sensing electromagnetic conditions in the outside environment;

a battery supply for providing electrical power;

a electromagnetic-powered battery recharger for recharging the battery;

electrical circuitry for producing glazing control voltages for driving the electrically-active elements of the electro-optical glazing supported within the window frame; and

a micro-computer chip for controlling the operation of the battery recharger and electrical circuitry and the production of glazing control voltages as required by a radiation flow control program stored within the programmed microcontroller.

33. An electro-optical window structure which is designed for integration within the heating/cooling system of a house, office building, factory or vehicle wherein the electro-optical glazing structure of claim 1 is supported within the electro-optical window structure in order to control the flow of electromagnetic radiation through the electro-optical window structure, while minimizing thermal loading upon the heating/cooling system thereof.