This work presents various engineering efforts in improving the performance of Cr:Znse (Chromium-doped Zinc Selenide) solid-state lasers. Prior study has shown that this laser material (Cr:ZnSe) is promising for demonstrating selfsimilar pulses due to its high gain and nonlinearity. However, it suffers from strong thermal lensing effect, which is the main obstacle for power scaling. In Chapter 2, production process of Cr:ZnSe including thermal diffusion doping, dicing and polishing is covered with detail. Numerical simulation is presented in Chapter 3 to describe the physical nature of the thermal lensing. A costeffective scheme of anti-reflective coating of the ZnSe is detailed in Chapter 4. And lastly, the performance of our Cr:ZnSe laser with the developed antireflective coating is evaluated and the experimental observations are discussed.