A wavelength swept laser with the sweep rate of 150 kHz using vibrations of optical fiber

摘要

In this report, we propose a high-speed wavelength swept light source using vibrations of an optical fiber and an external cavity laser. The end of an optical fiber coupling a semiconductor laser chip to a Littrow-mounted grating spectroscope is vibrated in the cantilever bending mode using a piezoelectric transducer. The incident angle to the grating is scanned at ultrasonic frequency, and the output wavelength is swept according to the vibration displacement amplitude. First, the relationship between the sweep span of wavelength and the linewidth is studied for different diameters of collimating lens. Second, the sweep characteristics of the output wavelength are observed in time domain. The maximum sweep rate of 167 kHz was achieved for the sweep span of 70 nm, the center wavelength of 1530 nm and the linewidth of 1.1 nm.