Wearable electro-optical device using electrochromic layer
View Patent ↗Flexible plastic screen for glasses, sunglasses or helmet faceshields with controlled light transmission based on applied electrical voltage. The screen consists of two transparent flexible conductive polymer electrodes disposed and an electrochromic layer disposed between them. The electrochromic layer is a homogeneous mixture of active electrochromic components dissolved in a polymer matrix. The electrochromic screen is operable to vary the light transmission of any wearable electro-optical devices, such as the glasses, for creating an effect of a blackout for augmented/virtual reality glasses.
1. A wearable electro-optical device comprising:
a. an electrochromic layer comprising electrochromic composition comprising a cathodic component in the form of a quaternary salt of dipyridine, an anodic component in the form of a ferrocene derivative or heterocyclic compound capable of switching between two oxidation states, a polymeric thickener and a solvent, wherein the cathodic component comprises a salt of cation of 1,1′-dialkyl-4,4′-dipyridinium (alkyl group) or 1,1-(alkane-alpha (alkaline spacer), omega-diyl)-bis-(1′-alkyl-4,4′-dipiridinium) with weakly coordinated anions;
b. a controller electrically coupled to the electrochromic layer and configured to apply a controlling voltage to the electrochromic layer in response to a received control command to vary light transmittance of the electrochromic layer; and
c. a power source for supplying electrical power to the controller.
2. The wearable electro-optical device of claim 1 , wherein the alkyl group is selected from C1-C8 saturated alkyl, benzyl, phenyl or substituted aryls.
3. The wearable electro-optical device of claim 1 , wherein the alkane spacer is selected from a C3-C5 alkane chain.
4. The wearable electro-optical device of claim 1 , wherein the anion of quaternary salt is non-nucleophilic and comprises BF4—, PF6—, ClO4—, CF3SO3— or (CF3SO2)2N— or (CF3SO2)3C—.
5. The wearable electro-optical device of claim 1 , wherein the polymeric thickener comprises a methyl methacrylate or its copolymer with acrylic and methacrylic acid or its salts, polyvinyl acetate, a polylactic acid, or poly-3-hydroxybutyrate or its copolymers.
6. The wearable electro-optical device of claim 1 , wherein the solvent comprises propylene carbonate, gamma-butyrolactone, gamma-valerolactone, N-methylpyrrolidone or di-, tri-polyethylene glycols or their esters.
7. The wearable electro-optical device of claim 1 comprising between 0.4% and 3.6% of the cathodic component, between 30% and 45% of polymer thickener, between 0.3 and 3.0% of the anodic component and the balance being the solvent.
8. The wearable electro-optical device of claim 1 , wherein the wearable electro-optical device is glasses.
9. The wearable electro-optical device of claim 1 , wherein the wearable electro-optical device is a helmet faceshield.
10. The wearable electro-optical device of claim 1 , further comprising at least one antioxidant.
11. The wearable electro-optical device of claim 10 , wherein the at least one antioxidant comprises a polyphenol.
12. The wearable electro-optical device of claim 10 , wherein the at least one antioxidant comprises a sterically hindered phenol.
13. The wearable electro-optical device of claim 10 , wherein the at least one antioxidant comprises an ionol.
14. The wearable electro-optical device of claim 1 , further comprising an ultraviolet filter.
15. The wearable electro-optical device of claim 14 , wherein the ultra-violet filter comprises a benzophenone.
16. The wearable electro-optical device of claim 14 , wherein the ultra-violet filter comprises a cinnamate.
17. The wearable electro-optical device of claim 1 , wherein the wearable optical device is virtual/augmented reality glasses.
18. The wearable electro-optical device of claim 17 , wherein the control command is received from virtual/augmented reality software.
19. The wearable electro-optical device of claim 18 , wherein in response to the control command, the controller causes the electrochromic layer to have a high light transmittance and wherein the control command is issued when the virtual/augmented reality software operates in an augmented reality mode.
20. The wearable electro-optical device of claim 18 , wherein in response to the control command, the controller causes the electrochromic layer to have a low light transmittance and wherein the control command is issued when the virtual/augmented reality software operates in a virtual reality mode.