Optical frequency-domain reflectometry using rapid wavelength tuning of a Cr^4+:forsterite laser

We present a cw chromium-doped forsterite laser that permits rapid wavelength tuning over a broad bandwidth and demonstrate the application of this source to frequency-domain ranging and optical tomography. The entire tuning range of 1200 to 1275 nm can be swept in less than $500 \mathit{\mu }\mathrm{s}$. This permits frequency-domain ranging to be performed with a scan rate of 2 kHz and an axial resolution of $15 \mathit{\mu }\mathrm{m}$.