Method for precisely measuring transit time of optical fiber Sagnac interferometer
A time-of-flight and precision measurement technology, applied in the direction of testing optical performance, can solve the problems of weakening performance stability, reducing static accuracy and resolution, etc., and achieve the effect of improving long-term stability and accuracy, and suppressing offset and error
Inactive Publication Date: 2014-09-03
ZHEJIANG UNIV
View PDF4 Cites 0 Cited by
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
When the half period of the modulation signal of the integrated phase modulator is not equal to the transit time of the fiber Sagnac interferometer, the system will generate an offset related to the error; the offset changes accordingly when the environment changes, so that the optical fiber A drift error component is superimposed on the output signal of the Sagnac interferometer, which reduces the static accuracy and resolution of the system and weakens the performance stability
Method used
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View moreImage
Smart Image Click on the blue labels to locate them in the text.
Smart ImageViewing Examples
Examples
Experimental program
Comparison scheme
Effect test
Embodiment Construction
[0035] The present invention will be further described below in conjunction with drawings and embodiments.
[0036] Such as figure 1 As shown, it includes a light source C1, a coupler C2 with a beam splitting ratio of 1:1, an integrated phase modulator C3, an optical fiber ring C4, a first detector C5, a second detector C6, a first analog-to-digital conversion channel C7, a second Two analog-to-digital conversion channels C8, clock C9, correlation processing algorithm C10, and transit time C11; the first and third pigtails of the coupler C2 with a beam splitting ratio of 1:1 are respectively connected to the light source C1 and the first detector C5 The third and fourth pigtails of the coupler C2 with a splitting ratio of 1:1 are respectively connected to the integrated phase modulator C3 and the second detector C6; the output end of the integrated phase modulator C3 is connected to the fiber ring C4 ; The first detector C5 obtains the sampling sequence S after passing throug...
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More PUM
Login to View More Abstract
The invention discloses a method for precisely measuring transit time of an optical fiber Sagnac interferometer. The method comprises the steps that: a second photoelectric detector is connected at a fourth tail fiber of a coupler of the optical fiber Sagnac interferometer; the modulated phase difference introduced by an integrated phase modulator is fixed and the optical power of a light source is changed; two photoelectric detectors convert the light intensity returned by the optical fiber and the light intensity output directly by the light source respectively to electric signals, and two analogue-to-digital converters based on one identical clock are used to sample the output signals of the two photoelectric detectors respectively; and two groups of sampling sequences obtained are processed relatively to obtain the time delay between the two sequences and calculate the transverse time of the optical fiber Sagnac interferometer with the combination of the sampling rate. According to the method, the transit time of the optical fiber Sagnac interferometer can be effectively measured, and a foundation is laid for the system to accurately select the period of the modulation signal, therefore, excursion and error caused by deviation of the transit time are prevented, and the long time stability and the precision of the optical fiber Sagnac interferometer are improved.
Description
technical field [0001] The invention relates to a signal processing method of an optical fiber Sagnac interferometer, in particular to a method for precise measurement of transit time of an optical fiber Sagnac interferometer. Background technique [0002] In 1913, the Frenchman Sagnac (G.Sagnac) invented a rotatable ring interferometer. Decompose a beam of light emitted by the same light source into two beams, let them travel in opposite directions in the same circular light path for a week, then meet, and then interfere on the screen, this is the Sagnac effect. Interferometers based on the Sagnac effect are called optical Sagnac interferometers, the most representative of which is the fiber Sagnac interferometer. [0003] Transit time is the time it takes for light to propagate for one week in a reciprocal optical path. The medium and high-precision fiber Sagnac interferometer mainly adopts a digital closed-loop solution. First, the optical system is modulated by an inte...
Claims
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More Application Information
Patent Timeline
Login to View More Patent Type & Authority Patents(China)
IPC IPC(8): G01M11/02
Inventor 古照勇陈杏藩刘承舒晓武
Owner ZHEJIANG UNIV