Figure 3. Fundamental cavity frequency and relative cavity length of laser operating on different wavelengths.
(a) Fundamental cavity frequency F and (b) relative difference of cavity length, ΔL, with respect to the central wavelength λ. The square symbols are the experimental data, showing the relationship of F versus λ of pulses. The circle symbols are calculated from the experimental data. In the calculation, ΔL is the difference of the total cavity length of any wavelength to a reference wavelength (1556.36 nm). ΔL is as large as ~11 mm when λ is from ~1556.36 to ~1564.25 nm. The solid lines are fit from the experimental data (square and circle symbols). The fit lines in (a, b) are expressed by F = 6.09874 − 2.34677 × 10−4·λ and ΔL = −2173.605 + 1.39657·λ, respectively.