US3684350A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Light beam polarization modulator
Assignee: Westinghouse Electric Corp
•
Filing: 1970-08-17
•
Granted: 1972-08-15
•
Expires: 1990-08-17
Abstract
Abstract A parallel cell electro-optical phase modulator is used in combination with two birefringent crystals and a half wave plate to produce polarization modulation of an incident light beam. A first birefringent crystal provides a lateral relative displacement between the two orthogonal components of the incident light beam to form two spaced light paths, one through each of the respective electro-optical crystals. The half wave plate rotates the linear polarization of the orthogonal components to allow a second birefringent crystal to recombine the orthogonal components into a single light beam.
Inventors
- 👤 John L Wentz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 18:31
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/03; G02F1/0305; G02F1/0311; H; H01; H01S; H01S3/00; H01S3/10; H01S3/11; H01S3/1123; H01S3/115
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
166 words
Light modulation apparatus for a source of polarized light comprising a birefringent element oriented for receiving an incident light beam parallel to an optic axis to resolve said beam into two orthogonal components in spaced parallel lights paths, first and second birefringent electro-optical crystals having substantially the same index of refraction arranged, respectively, in said parallel light paths, half-wave plate arranged across said light paths a second birefringent element having the same characteristics as said first birefringent element and having its principal axis orthOgonal to the principal axis of said first birefringent element for receiving light from said parallel paths and recombining them into a single light beam substantially colinear with said incident light beam, said birefringent elements being so disposed about the axis of the incident light that their respective optic axes are 45* with respect to the electric vector of said incident light beam and means for applying a D.C. potential across said electro-optical elements to vary the index of refraction of said crystal.
Claim 2
Dependent Claim
166 words
Light modulation apparatus for a source of polarized light comprising a birefringent element oriented for receiving an incident light beam parallel to an optic axis to resolve said beam into two orthogonal components in spaced parallel lights paths, first and second birefringent electro-optical crystals having substantially the same index of refraction arranged, respectively, in said parallel light paths, half-wave plate arranged across said light paths a second birefringent element having the same characteristics as said first birefringent element and having its principal axis orthOgonal to the principal axis of said first birefringent element for receiving light from said parallel paths and recombining them into a single light beam substantially colinear with said incident light beam, said birefringent elements being so disposed about the axis of the incident light that their respective optic axes are 45* with respect to the electric vector of said incident light beam and means for applying a D.C. potential across said electro-optical elements to vary the index of refraction of said crystal.
Claim 3
Dependent Claim
72 words
A combination as set forth in claim 1, in which said electro-optical crystals has substantial the same index of refraction and have the respective principal optic axes effectively optically optically perpendicular to each other, said crystals having substantially the same length and being subjected to the same environmental conditions, and means for supplying a modulation voltage to said crystals with the electric fields parallel to the respective z axes of said crystals.
Claim 4
Dependent Claim
30 words
The combination as set forth in claim 2 and means for converting polarization modulation of said orthogonal light components into intensity modulation of the light from said combined orthogonal components.
Claim 5
Dependent Claim
43 words
The combination as set forth in claim 2 in which the x axis of one of said electro-optical crystals is parallel to the y axis of the other of said crystals and the z axis of both crystals are perpendicular to each other.
Claim 6
Dependent Claim
29 words
The combination set forth in claim 4 with means for converting polarization modulation of said orthogonal light components into intensity modulation of the light from said combined orthogonal components.
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) | 1975-08-15 | 1976-02-14 | 1976-08-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-15 | 1980-02-14 | 1980-08-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-15 | 1984-02-14 | 1984-08-15 | $7700.00 | Window Closed / Lapsed |