Low melting point ionic liquids for infra-red liquid lens design

Patent metadata

Field	Value
Publication number	US-12306373-B2
Application number	US-202017426914-A
Country	US
Kind code	B2
Filing date	Jan 23, 2020
Priority date	Feb 1, 2019
Publication date	May 20, 2025
Grant date	May 20, 2025

Abstract

A liquid lens can include a lens body forming a cavity with a conducting liquid and an insulating liquid disposed therein, the conducting liquid substantially immiscible with the insulating liquid to define an interface between the conducting and insulating liquids. The conducting liquid can include an ionic compound of either a dicyanamide anion and a cation counterion, or a tricyanomethanide anion and a cation counterion, the dicyanamide anion having the formula the tricyanomethanide anion having the formula and the cation counterion is one of an imidazolium, a pyrrolidininium, a piperidinium, a phosphonium, a pyridinium, a pyrrolinium or a sulfonium cation. The ionic compound of the conducting liquid can be N-methyl-N-ethylpyrrolidinium dicyanamide, 1-ethyl-3-methylimidazolium dicyanamide, 1-butyl-1-methylpyrrolidinium tricyanomethanide, or 1-ethyl-3-methylimidazolium tricyanomethanide, among others. The conducting liquid can have transmittance of at least 50% over a thickness of 1 mm for electromagnetic waves having wavelength of 1550 nm.

First claim

What is claimed is:

1. A liquid lens comprising:
a lens body comprising a cavity; and
a conducting liquid and an insulating liquid disposed within the cavity, the conducting liquid being substantially immiscible with the insulating liquid, whereby an interface is defined between the conducting liquid and the insulating liquid;
wherein the conducting liquid comprises an ionic compound of either a dicyanamide anion and a cation counterion, or a tricyanomethanide anion and a cation counterion, the dicyanamide anion having the general formula

the tricyanomethanide anion having the general formula

and the cation counterion is one of an imidazolium, a pyrrolidininium, a piperidinium, a phosphonium, a pyridinium, a pyrrolinium, or a sulfonium cation;
wherein a density of the conducting liquid is within 0.10 g/cm 3 of a density of the insulating liquid at 20 degrees Celsius;
wherein at least one of the density of the conducting liquid or the density of the insulating liquid is about or greater than 1.0 g/cm 3 at 20 degrees Celsius.

2. The liquid lens of claim 1 , wherein, the conducting liquid is in a liquid phase between −20 degrees Celsius and 70 degrees Celsius.

3. The liquid lens of claim 1 , wherein, the cation counterion is one of 1-ethyl-3-methylimidazolium cation, 1-allyl-3-methylimidazolium cation, 1-benzyl-3-methylimidazolium cation, 1-butyl-3-methylimidazolium cation, 1-hexyl-3-methylimidazolium cation, 1-ethyl-3-methylimidazolium cation, N-ethyl-N-methylpyrrolidinium cation, 1-butyl-1-methylpyrrolidinium cation, or trihexyltetradecylphosphonium cation.

4. The liquid lens of claim 1 , wherein, the ionic compound of the conducting liquid is one of N-ethyl-N-methylpyrrolidinium dicyanamide, 1-ethyl-3-methylimidazolium dicyanamide, 1-butyl-1-methylpyrrolidinium tricyanomethanide, or 1-ethyl-3-methylimidazolium tricyanomethanide.

5. The liquid lens of claim 1 , wherein the conducting liquid has a transmittance of at least 50% over a thickness of 1 mm for electromagnetic waves having a wavelength of 1550 nm.

6. The liquid lens of claim 1 , wherein the conducting liquid has a transmittance of at least 90% for electromagnetic waves having a wavelength of 1550 nm.

7. The liquid lens of claim 1 , wherein the ionic compound is at least 97 percent by weight of the total weight of the conducting liquid.

8. The liquid lens of claim 1 , wherein:
the insulating liquid comprises dodecane, (25-35% nonafluorohexylmethylsiloxane) (65-75% dimethylsiloxane) copolymer, bis(nonafluorohexyl) tetramethyldisiloxane, and polydimethylsiloxane; and
the ionic compound of the conducting liquid is 1-butyl-1-methylpyrrolidinium tricyanomethanide.

9. The liquid lens of claim 1 , wherein:
the insulating liquid comprises dodecane, (25-35% nonafluorohexylmethylsiloxane) (65-75% dimethylsiloxane) copolymer, bis(nonafluorohexyl) tetramethyldisiloxane, hexamethyldigermane, and hexaethyldigermane; and
the ionic compound of the conducting liquid is 1-ethyl-3-methylimidazolium dicyanamide.

10. The liquid lens of claim 1 , wherein the insulating liquid comprises greater than or equal to 12% and less than or equal to 30% hydrocarbon.

11. The liquid lens of claim 10 , wherein the hydrocarbon comprises dodecane.

12. The liquid lens of claim 1 ,
wherein the insulating liquid comprises at least one of a fluorinated Si-based compound or a Ge-based compound.

13. The liquid lens of claim 12 , wherein the insulating liquid comprises the fluorinated Si-based compound, and wherein a refractive index of the insulating liquid is less than or equal to 1.430.

14. The liquid lens of claim 13 , wherein the insulating liquid comprises at least 38% of the fluorinated Si-based compound.

15. The liquid lens of claim 13 , wherein the fluorinated Si-based compound has formula (Ia), (Ib), and/or (Ic)

wherein:
each of R1, R2 and R′ independently represents alkyl, (hetero)aryl, (hetero)arylalkyl, (hetero)arylalkenyl, or (hetero)arylalkynyl;
m is between 1 and 20; and
in formula (Ic), n is greater than 2.

16. The liquid lens of claim 12 , wherein the insulating liquid comprises the Ge-based compound, and wherein a refractive index of the conducting liquid is greater than a refractive index of the insulating liquid.

17. The liquid lens of claim 1 ,
wherein the insulating liquid comprises a Si-based compound; and
wherein a refractive index of the insulating liquid is less than or equal to 1.472.

18. The liquid lens of claim 17 , wherein the refractive index of the insulating liquid is less than or equal to 1.43.

19. The liquid lens of claim 17 , wherein the Si-based compound comprises at least one of hexamethyidisilane, diphenyldimethylsilane, chlorophenyltrimethylsilane, phenyltrimethyl-silane, phenethyltris(trimethylsiloxy) silane, phenyltris(trimethylsiloxy) silane, polydimethylsiloxane, tetraphenyltetramethyltrisiloxane, poly (3,3,3-trifluoropropylmethylsiloxane), 3,5,7-triphenylnonamethyl-pentasiloxane, 3,5-diphenyloctamethyltetrasiloxane, 1,1,5,5-tetraphenyl-1,3,3,5-tetramethyl-trisiloxane, hexamethylcyclotrisiloxane, n-octyltris(trimethylsiloxy)silane, or bis(nonafluorohexyl)tetramethyldisiloxane and (25-35% nonafluorohexylmethylsiloxane) (65-75% dimethylsiloxane) copolymer.

Assignees

• Corning Inc
• Lg Innotek Co Ltd

Inventors

• Burger Benjamin Jean-Baptiste Francois

Classifications

• C07D295/037

  with quaternary ring nitrogen atoms · CPC title

• C07C255/05

  containing at least three cyano groups bound to the carbon skeleton · CPC title

• C01C3/16

  Cyanamide; Salts thereof ({C01C3/001, C01C3/002 takes precedence}; dicyandiamide C07C279/28) · CPC title

• C07D233/58 Primary

  with only hydrogen atoms or radicals containing only hydrogen and carbon atoms, attached to ring nitrogen atoms · CPC title

• G02B2207/115

  Electrowetting · CPC title