You are given a 1 kW CO laser at 10.6 m with a Gaussian beam waist at its flat output mirroir of wo = 10 mm. 3.1 Optimum focusing on a target You are given a collection of lenses that can sustain at most a Gaussian beam of w= 23 mm. Your target is at 60 from the laser. To achieve a maximum intensity on target, you can select a system of two lenses 1 m apart, the first one being located at the output mirror. What is the maximum intensity you can achieve on target? 3.2 Sketch the optimal lens arrangement 3.3 Feedback on the laser Estimate the amount of light reflected back into the laser, assuming the "target" to be a 6 mm diameter plane reflector. Knowing that the laser was operated at 80% of saturation, and that the laser output coupler had 10%