Optics: measuring and testing – By polarized light examination – With birefringent element
Patent
1997-01-10
1998-02-03
Pham, Hoa Q.
Optics: measuring and testing
By polarized light examination
With birefringent element
324 96, G01J 400
Patent
active
057150583
ABSTRACT:
In order to detect, in particular, a high electric voltage (8), use is made of an electrooptic sensor with an electrooptic crystal (4) such as is applied in Pockels cells. Light is irradiated into the electrooptic crystal (4) in a linearly polarized fashion from a light source (L) via a fiber coupler (FK), a fiber-optic cable (F1), a collimator (K1), a 1st polarizer (P1), a beam splitter (1), and 1st and 2nd glass plates (2, 3). Located at the end face of said crystal is a 3rd glass plate (5) having a layer electrode (6) which simultaneously acts as a mirror (7) and retroreflects the incident light through the electrooptic crystal (4). One component beam (T1) of the reflected light passes back to a 1st light detector (D1) via the beam splitter (1) and the 1st polarizer (P1), now acting as an analyzer. A 2nd component beam (T2) passes to a 2nd light detector (D2) via a .lambda./4-delay plate (9), a 2nd polarizer (P2), a 90.degree. prism (10), a collimator (K2) and a 2nd fiber-optic cable (F2). Light intensities (I.sub.1) and (I.sub.2) are evaluated by means of a microprocessor (14). Owing to the fact that the two phase-shifted light signals are derived from a common optical channel, an intrinsic birefringence of the electrooptic crystal (4) does not affect their phase difference. A 9.degree. prism can be used instead of a mirror (7) for reversing the light. Input and output channels of the light can be separate. Ways are specified for the temperature compensation of a measurement result signal (S).
REFERENCES:
patent: 3516727 (1970-06-01), Hickey et al.
patent: 3675125 (1972-07-01), Jaecklin
patent: 3693082 (1972-09-01), Jaecklin
patent: 3743929 (1973-07-01), Lesueur
patent: 4749854 (1988-06-01), Martins
patent: 4855591 (1989-08-01), Nakamura et al.
patent: 4904931 (1990-02-01), Miller
patent: 4970385 (1990-11-01), Tatsuno et al.
patent: 5038029 (1991-08-01), Marten et al.
Bohnert Klaus
Nehring Jurgen
ABB Research Ltd.
Pham Hoa Q.
LandOfFree
Method and device for the optical determination of a physical qu does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and device for the optical determination of a physical qu, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and device for the optical determination of a physical qu will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-667482