US3799650A
Expired / Lapsed
US
⏱️ 0.0 years remaining
One-way light valve
Assignee: Research Frontiers Inc
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Filing: 1972-04-12
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Granted: 1974-03-26
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Expires: 1992-04-12
Abstract
Abstract A light valve is disclosed in combination with a one-way mirror (a mirror which reflects light in one direction and transmits it in the other direction). The light valve is positioned on the viewing side (the transmitting direction) of the mirror so that the mirror can substantially attenuate the light that is generated on that side of the mirror. The light on the viewing side of the mirror can thus be increased substantially without significantly interfering with the operation of the mirror.
Inventors
- 👤 R Saxe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 23:00
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/17; G02F1/172
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
244 words
A one-way mirror light valve including a cell for containing a fluid suspension of colloidal particles dispersed therein capable of having their orientation changed by an electric or magnetic field to change the transmission of light through the suspension, said cell having first and second wall sections spaced apart a distance which is small compared to the lateral dimensions of the sections, and means for applying an electric or magnetic field to the suspension between said wall sections to change the light transmission thereof, said first wall having a transparent reflective and conductive coating thereon, and said second wall having a transparent conductive coating thereon, said reflective coating being a partially reflective mirror and wherein light incident on the second wall in passing through the fluid suspension is rendered substantially less intense and nonvisible proximate the first wall when compared to the intensity of the light incident on the first wall that is reflected from the mirror without passing through the fluid suspension and wherein light incident on the second wall that is reflected by the mirror and thereby through the fluid suspension twice is rendered substantially less intense and non visible proximate the second wall when compared to the light incident on the first wall which passes through the fluid suspension only once and means to vary the intensity of the electric or magnetic field to control the light transmission and thereby control the intensity of the light passing through the fluid suspension.
Claim 2
Dependent Claim
244 words
A one-way mirror light valve including a cell for containing a fluid suspension of colloidal particles dispersed therein capable of having their orientation changed by an electric or magnetic field to change the transmission of light through the suspension, said cell having first and second wall sections spaced apart a distance which is small compared to the lateral dimensions of the sections, and means for applying an electric or magnetic field to the suspension between said wall sections to change the light transmission thereof, said first wall having a transparent reflective and conductive coating thereon, and said second wall having a transparent conductive coating thereon, said reflective coating being a partially reflective mirror and wherein light incident on the second wall in passing through the fluid suspension is rendered substantially less intense and nonvisible proximate the first wall when compared to the intensity of the light incident on the first wall that is reflected from the mirror without passing through the fluid suspension and wherein light incident on the second wall that is reflected by the mirror and thereby through the fluid suspension twice is rendered substantially less intense and non visible proximate the second wall when compared to the light incident on the first wall which passes through the fluid suspension only once and means to vary the intensity of the electric or magnetic field to control the light transmission and thereby control the intensity of the light passing through the fluid suspension.
Claim 3
Dependent Claim
291 words
A one-way mirror light valve including a cell for containing a fluid suspension of colloidal particles dispersed therein capable of having their orientation changed by an electric or magnetic field to change the transmission of light through the suspension, said cell having first and second wall sections spaced apart a distance which is small compared to the lateral dimensions of the sections, and means for applying an electric or magnetic field to the suspension between said wall sections to change the light transmission thereof, said first wall having a transparent conductive coating thereon, and said second wall having a transparent conductive coating thereon, a reflective mirror, having first and second sides positioned proximate said first wall with said first side facing toward said first wall and said second side facing away from said first wall, said reflective mirror being a partially reflective mirror and wherein light incident on the second wall in passing through the fluid suspension is rendered substantially less intense and non-visible proximate the second side of the mirror when compared to the intensity of the light incident on the second side of the mirror that is reflected from the mirror without passing through the fluid suspension and wherein light incident on the second wall that is reflected by the mirror and thereby passes through the fluid suspension twice is rendered substantially less intense and non-visible proximate the second wall when compared to the light incident on the second side of the mirror which passes through the fluid suspension only once to reach the area proximate the second wall and means to vary the intensity of the electric or magnetic field to control the light transmission and thereby control the intensity of the light passing through the fluid suspension.
Claim 4
Dependent Claim
291 words
A one-way mirror light valve including a cell for containing a fluid suspension of colloidal particles dispersed therein capable of having their orientation changed by an electric or magnetic field to change the transmission of light through the suspension, said cell having first and second wall sections spaced apart a distance which is small compared to the lateral dimensions of the sections, and means for applying an electric or magnetic field to the suspension between said wall sections to change the light transmission thereof, said first wall having a transparent conductive coating thereon, and said second wall having a transparent conductive coating thereon, a reflective mirror, having first and second sides positioned proximate said first wall with said first side facing toward said first wall and said second side facing away from said first wall, said reflective mirror being a partially reflective mirror and wherein light incident on the second wall in passing through the fluid suspension is rendered substantially less intense and non-visible proximate the second side of the mirror when compared to the intensity of the light incident on the second side of the mirror that is reflected from the mirror without passing through the fluid suspension and wherein light incident on the second wall that is reflected by the mirror and thereby passes through the fluid suspension twice is rendered substantially less intense and non-visible proximate the second wall when compared to the light incident on the second side of the mirror which passes through the fluid suspension only once to reach the area proximate the second wall and means to vary the intensity of the electric or magnetic field to control the light transmission and thereby control the intensity of the light passing through the fluid suspension.
Claim 5
Dependent Claim
74 words
The one-way mirror light valve of claim 2 including a second cell for containing a fluid suspension substantially identical to said first mentioned cell and positioned on the other side of said mirror from said first mentioned cell and wherein a second means for applying an electric or magnetic field to this suspension is provided which is substantially identical to said first mentioned means for applying an electric or magnetic field to the suspension.
Claim 6
Dependent Claim
17 words
The one-way mirror light valve of claim 2 wherein the fluid suspension is a suspension of herapathite.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-03-25 | 1977-09-24 | 1978-03-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-03-25 | 1981-09-24 | 1982-03-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-03-25 | 1985-09-24 | 1986-03-26 | $7700.00 | Window Closed / Lapsed |