Wavelength Stabilization of Dual-Wavelength Oscillation in Electronically Tuned Ti:Al₂O₃Laser

Abstract

We investigate the stability of the wavelength in a dual-wavelength-oscillated Ti:Al2O3 laser with an acousto-optic tunable filter (AOTF). We observe wavelength drift when wavelength is switched. We also clarify that the wavelength drift is induced by the temperature distribution in the AOTF. Furthermore, we propose a new method of temperature control of the AOTF to stabilize the wavelength. We achieve the stabilization of wavelength drift to within ±0.01 nm by feeding another RF signal into the AOTF to control the temperature inside the AOTF.

Spectral Characterization of Near-Infrared Acousto-optic Tunable Filter (AOTF) Hyperspectral Imaging Systems Using Standard Calibration Materials

“…Efficiently solving both is essential as the majority of methods for analysis of hyperspectral images rely on a priori knowledge extracted from large spectral databases, serving as the basis for reliable qualitative or quantitative analysis of various samples. Additionally, when using an AOTF without temperature control of the crystal 20 or when substantially changing the optical setup, recalibration of the AOTF device may be required. The existing studies on the spectral calibration of AOTF hyperspectral imaging systems, which are concerned with finding frequency-wavelength characteristics or so-called spectral tuning curves, differ in terms of accuracy, complexity, and cost.…”

Multi-Wavelength Spectroscopic Application Using Rapid and Random Wavelength-Tuned Mid-Infrared Light Source

“…The variation in temperature of the AOTF, which is induced by the RF signals, causes the wavelength drift of the Ti:Al 2 O 3 laser. 15,16) It is obvious that the drift of the dual wavelengths affects the wavelength stability of difference frequencies. Figures 3(a) and 3(b) show the stability of difference frequencies at 7.724 and 7.152 mm, which were generated by mixing dual wavelengths of 764.66 and 848.68 nm, and 790.58 and 888.83 nm, respectively.…”

“…The shifts of the dual wavelengths of 764.66 and 848.68 nm, and 790.58 and 888.83 nm were 0.23 and 0.28 nm, and 0.06 and 0.07 nm, respectively, over 40 min. 16) The wavelength of the difference frequency was determined from the measured dual wavelengths. The stability at 7.724 and 7.152 mm was less than AE1:1 Â 10 À3 mm over 40 min.…”