Simple technique for improving the resolution of the delayed self-heterodyne method

✍ Scribed by Tsuchida, Hidemi

• Book ID: 115417885
• Publisher: Optical Society of America
• Year: 1990
• Tongue: English
• Weight: 355 KB
• Volume: 15
• Category: Article
• ISSN: 0146-9592
• DOI: 10.1364/OL.15.000640

✦ Synopsis

A new technique is proposed and demonstrated for improving the resolution of the delayed self-heterodyne method for laser spectral linewidth measurement.

The delay time between two laser beams is increased by the use of multipass transmission in an optical fiber ring interferometer containing a frequency shifter. This technique does not require a longer fiber or complicated curve fitting of the observed spectra.

Narrow-linewidth semiconductor lasers are highly desirable for applications such as coherent optical communication and precise interferometric measurement.

The delayed self-heterodyne method (DSHM), which was proposed by Okoshi et at. 1 ' 2 in 1980, has been