RT - Journal Article T1 - Spectrum Width Measurement of narrow linewidth lasers based on self Homodyne method using phase modulator JF - opsi YR - 2015 JO - opsi VO - 21 IS - 0 UR - http://opsi.ir/article-1-753-en.html SP - 905 EP - 908 K1 - Narrow linewidth Laser K1 - Lorentzian K1 - Phase modulator K1 - Self-Homodyne AB - In this paper, a modified Self Homodyne using phase modulator and short delay fiber length in order to measure the spectral width of a laser diode is presented. Due to short delay fiber, 1/f low frequency noise has been filtered from spectrum. So possibility of measuring the broadening of the spectrum due to white noise (the width of the Lorentzian spectrum) is provided. By use of this method, the linewidth of a 1550 nm laser diode with 83 kHz spectrum width has been measured. The result data of linewidth measurement using RF spectrum Analyzer (directly) and software are compared. LA eng UL http://opsi.ir/article-1-753-en.html M3 ER -