Apparatus and method for measuring characteristics of optical pulses
US6057919A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Jul 11, 1997 |
| Grant date | May 2, 2000 |
| Priority date | — |
| Expiry date | Jul 11, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J11/00
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
In an optical pulse characteristic measuring apparatus, optical pulses to be measured are introduced at the incident end, and split at an beam splitter. A first resultant light beam is reflected by a mirror as a local oscillation light of homodyne detection and is adjusted in a delay element so as to have the same optical path length as that of the second resultant light beam. Subsequently, the first light beam is led to an optical mixer. The second light beam is reflected by a mirror, which is controlled by a signal from a signal generator for modulation of optical path length difference. The second light beam is then reflected by a delay element and is led to the optical mixer. The two light beams combined at the optical mixer are detected by optical detectors. The AC signal component generated by modulation of the optical path length difference is amplified up to a measurable voltage by a differential amplifier. A bandpass filter passes only the AC signal component generated by modulation of the optical path length difference, thereby improving the S-N ratio. By using an AC voltmeter to measure the AC signal component corresponding to the delay of the delay element for correlati…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.