US5346789A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Oriented biological material for optical information storage and processing
Assignee: Cornell Research Foundation Inc
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Filing: 1992-11-30
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Granted: 1994-09-13
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Expires: 2012-11-30
Abstract
Abstract A stable, image-retaining, optically switchable film produced from a purple membrane in a high-pH polyvinyl alcohol solution forms an optical memory for data storage. The film, when dry, can be exposed to light to convert BR molecules to their M state, which is stable, and which allows long-term image storage. The image can be erased by exposing the film to yellow light to thereby switch all the molecules to the M state, and then a reverse image can be obtained using blue light. By controlling the location and wavelength of the incident light, pixels can be selected and exposed for information storage.
Inventors
- 👤 Aaron Lewis
- 👤 Zhongping Chen
- 👤 Hiroyuki Takei
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 14:56
CPC Classifications
B; B82; B82Y; B82Y10/00; G; G02; G02F; G02F1/00; G02F1/35; G02F1/355; G02F1/361; G11; G11B; G11B11/00; G11B11/12; G11B7/00; G11B7/004; G11B7/0045; G11B7/00455; G11B7/005; G11B7/0052; G11B7/0055; G11B7/00552; G11B7/24; G11B7/241; G11B7/242; G11B7/244; Y; Y10; Y10S; Y10S430/00; Y10S430/146; Y10S430/163
Claims Analysis
Total Claims: 30
Claim 1
Independent Claim
183 words
A method of producing a stable reversible, high resolution image on a bacteriorhodopsin (BR)-containing film, comprising: dissolving polyvinyl alcohol PVA in a buffer to form a PVA solution; dissolving a BR material which is optically switchable between first and second states in a buffer to form a BR solution; adjusting the pH of said BR solution to produce a high pH BR solution; mixing said PVA and high pH BR solutions to form a BR-PVA solution; forming a film of said BR-PVA solution; drying said film; directing light of a first spectral range to selected locations in said film to expose selected BR molecules in said film to an optical image to switch the selected BR molecules from their first to their second state and thereby to switch the color of said exposed BR molecules to provide a corresponding image; and directing light of a second spectral range to illuminate selected locations in said film to cause previously exposed BR molecules to emit light at a second harmonic of the illuminating light in said second spectral range to thereby nondestructively detect said image.
Claim 2
Independent Claim
183 words
A method of producing a stable reversible, high resolution image on a bacteriorhodopsin (BR)-containing film, comprising: dissolving polyvinyl alcohol PVA in a buffer to form a PVA solution; dissolving a BR material which is optically switchable between first and second states in a buffer to form a BR solution; adjusting the pH of said BR solution to produce a high pH BR solution; mixing said PVA and high pH BR solutions to form a BR-PVA solution; forming a film of said BR-PVA solution; drying said film; directing light of a first spectral range to selected locations in said film to expose selected BR molecules in said film to an optical image to switch the selected BR molecules from their first to their second state and thereby to switch the color of said exposed BR molecules to provide a corresponding image; and directing light of a second spectral range to illuminate selected locations in said film to cause previously exposed BR molecules to emit light at a second harmonic of the illuminating light in said second spectral range to thereby nondestructively detect said image.
Claim 3
Dependent Claim
24 words
The method of claim 1, further including impregnating said exposed film with a high pH solution to fix said optical image in said film.
Claim 4
Dependent Claim
37 words
The method of claim 1, further including forming and drying plural layers of said film to form a three dimensional structure and exposing selected locations and selected layers in said structure to produce a three-dimensional data image.
Claim 5
Dependent Claim
39 words
The method of claim 3, wherein the step of directing light of a first spectral range includes directing light to selected locations in selected layers to switch the state of BR molecules so exposed to produce a three-dimensional image.
Claim 6
Dependent Claim
55 words
The method of claim 4, wherein the step of directing light of a second spectral range includes directing light to illuminate selected locations in selected layers to cause previously exposed BR molecules to emit light at a second harmonic of the illuminating light in said second spectral range to thereby nondestructively detect said three-dimensional image.
Claim 7
Dependent Claim
44 words
The method of claim 4, wherein the step of directing light of said first spectral range includes focusing a beam of light onto a selected location in a selected layer to produce light of sufficient intensity to produce two-photon excitation of exposed BR molecules.
Claim 8
Independent Claim
192 words
A method of producing an oriented bacteriorhodopsin (BR)-polyvinyl alcohol (PVA) film capable of receiving a stable image for optical information storage, comprising: dissolving in a buffer a BR material capable of responding to light of a first spectral range of light energy to change its structure to an intermediate state which is capable of responding to a second spectral range of light energy to change back to said BR material, to thereby form a BR solution; dissolving in a buffer a PVA material to thereby form a PVA solution; mixing said BR solution and said PVA solution to produce a BR-PVA solution; spreading a volume of the BR-PVA solution on a substrate to form a BR-PVA film from said BR-PVA solution; diffusing a high pH buffer into said film before completely drying to control the orientation of said BR material in said film and to increase the stability of said BR intermediate state: and drying said film to a thickness of about 150 to 200 microns with an optical density of about 0.15, with the film having an absorption spectrum substantially the same as that of said BR material in said solution.
Claim 9
Independent Claim
192 words
A method of producing an oriented bacteriorhodopsin (BR)-polyvinyl alcohol (PVA) film capable of receiving a stable image for optical information storage, comprising: dissolving in a buffer a BR material capable of responding to light of a first spectral range of light energy to change its structure to an intermediate state which is capable of responding to a second spectral range of light energy to change back to said BR material, to thereby form a BR solution; dissolving in a buffer a PVA material to thereby form a PVA solution; mixing said BR solution and said PVA solution to produce a BR-PVA solution; spreading a volume of the BR-PVA solution on a substrate to form a BR-PVA film from said BR-PVA solution; diffusing a high pH buffer into said film before completely drying to control the orientation of said BR material in said film and to increase the stability of said BR intermediate state: and drying said film to a thickness of about 150 to 200 microns with an optical density of about 0.15, with the film having an absorption spectrum substantially the same as that of said BR material in said solution.
Claim 10
Dependent Claim
29 words
The method of claim 7, further including forming and drying plural layers of said film on said substrate to form an oriented film capable of receiving a three-dimensional image.
Claim 11
Dependent Claim
50 words
The method of claim 7, further including imaging said dried film with light of said first spectral range to shift selected molecules of said BR material to said intermediate state to produce in said dried film an optical image, said image having a color corresponding to said first spectral range.
Claim 12
Dependent Claim
26 words
The method of claim 9, further including directing light of a third spectral range onto said optical image on said film to nondestructively illuminate said image.
Claim 13
Dependent Claim
34 words
The method of claim 10, further including directing light of said first spectral range onto said film to convert remaining BR molecules of said BR material to said intermediate state to erase said image.
Claim 14
Dependent Claim
48 words
The method of claim 11, further including producing a new image on said film by imaging said film with light of said second spectral range to shift selected imaged intermediate state molecules to their BR state, said new image having a color corresponding to said second spectral range.
Claim 15
Dependent Claim
27 words
The method of claim 12, further including directing light of a fourth spectral range onto said new image on said film to nondestructively illuminate said new image.
Claim 16
Dependent Claim
38 words
The method of claim 12, further including directing light of said second spectral range onto said film to convert remaining intermediate state molecules to their BR state to erase said new image by either 1-photon or 2-photon absorption.
Claim 17
Dependent Claim
43 words
The method of claim 9, further including directing light having a frequency out of the absorption range of said BR material but having a second harmonic frequency near the absorption range of said BR material, onto said film to read said image nondestructively.
Claim 18
Dependent Claim
26 words
The method of claim 9, further including detecting said dried film image by measuring electrical signals produced by said BR material and by said intermediate material.
Claim 19
Dependent Claim
23 words
The method of claim 7, wherein the step of diffusing a high pH buffer includes adjusting the pH of the buffer to 10.
Claim 20
Dependent Claim
39 words
The method of claim 1, further including exposing the entire surface of said film to light of said first spectral range to switch the state of all previously unexposed BR molecules to their second state to erase said image.
Claim 21
Dependent Claim
44 words
The method of claim 18, further including directing light of a third spectral range to illuminate selected locations in said film to expose selected BR molecules to shift them from their second state back to their first state to provide a corresponding reversed-color image.
Claim 22
Dependent Claim
36 words
The method of claim 19, further including directing light of said third spectral range to expose the entire surface of said film to return all BR molecules to their first state to erase said reversed-color image.
Claim 23
Dependent Claim
31 words
The method of claim 18, further including directing light of a third spectral range to expose the entire surface of said film to return said BR molecules to their first state.
Claim 24
Dependent Claim
48 words
The method of claim 1, wherein the step of directing light of a second spectral range includes directing light having a wavelength outside the absorption spectrum of BR molecules in their second state but having a second harmonic wavelength within said absorption spectrum to nondestructively detect said image.
Claim 25
Independent Claim
187 words
A method of producing an oriented bacteriorhodopsin (BR)-polyvinyl alcohol (PVA) film capable of receiving a stable image for optical information storage, comprising: dissolving in a buffer a BR material capable of responding to light of a first spectral range of light energy to change its structure to an intermediate material which is capable of responding to a second spectral range of light energy to change back to said BR material, to thereby form a BR solution; dissolving in a buffer a PVA material to thereby form a PVA solution; mixing said BR solution and said PVA solution to produce a BR-PVA solution; spreading a volume of the BR-PVA solution on a substrate to form a BR-PVA film from said BR-PVA solution; and diffusing a high pH buffer into said film before completely drying to control the orientation of said BR material in said film and to increase the stability of said BR intermediate state; and drying said film to a thickness to produce an optical density of about 0.15, with the film having an absorption spectrum substantially the same as that of said BR material in solution.
Claim 26
Independent Claim
187 words
A method of producing an oriented bacteriorhodopsin (BR)-polyvinyl alcohol (PVA) film capable of receiving a stable image for optical information storage, comprising: dissolving in a buffer a BR material capable of responding to light of a first spectral range of light energy to change its structure to an intermediate material which is capable of responding to a second spectral range of light energy to change back to said BR material, to thereby form a BR solution; dissolving in a buffer a PVA material to thereby form a PVA solution; mixing said BR solution and said PVA solution to produce a BR-PVA solution; spreading a volume of the BR-PVA solution on a substrate to form a BR-PVA film from said BR-PVA solution; and diffusing a high pH buffer into said film before completely drying to control the orientation of said BR material in said film and to increase the stability of said BR intermediate state; and drying said film to a thickness to produce an optical density of about 0.15, with the film having an absorption spectrum substantially the same as that of said BR material in solution.
Claim 27
Dependent Claim
11 words
The method of claim 23, further including degassing said BR-PVA solution.
Claim 28
Dependent Claim
21 words
The method of claim 23, further including cleaning a glass substrate and thereafter spreading said BR-PVA solution on the glass substrate.
Claim 29
Dependent Claim
18 words
The method of claim 23, further including drying said BR-PVA film with a uniform flow of filtered air.
Claim 30
Dependent Claim
24 words
The method of claim 23, wherein the step of drying includes uniformly drying the film to produce a film thickness of about 150-200 microns.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-09-12 | 1998-03-14 | 1998-09-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-09-12 | 2002-03-14 | 2002-09-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-09-12 | 2006-03-14 | 2006-09-13 | $7700.00 | Window Closed / Lapsed |