Tunable lasers have played an important role in a variety of industrial fields, by supplying stable output over a wide range of wavelengths. The external-cavity diode laser (ECDL) is widely used, because it provides a relatively broad tuning range, compact configuration, and easy control. In this paper, a new design is proposed for the Littman ECDL. The new design possesses a mode-hop-free single mode which is capable of tuning over a wide range of 17 nm, as a result of reconfiguring the pivot point location. Simulation and experimental studies were performed to verify our proposed method.

The computer controlled optical surfacing (CCOS) technique provides superior fabrication performance for optical mirrors when compared to the conventional method, which relies heavily on the skill of the optician. The CCOS technique provides improvements in terms of mass production, low cost, and short polishing time, and are achieved by estimating and controlling the moving speed of the tool and toolpath through a numerical analysis of the tool influence function (TIF). Hence, the exact estimation of various TIFs is critical for high convergence rates and high form accuracy in the CCOS process. In this paper, we suggest a new model for TIFs, which can be applied for various tool shapes, different velocity distributions, and non-uniform tool pressure distributions. Our proposed TIFs were also verified by comparisons with experimental results. We anticipate that these new TIFs will have a major role in improving the form accuracy and shortening the polishing time by increasing the accuracy of the material removal rate.