Figure 2
From: Control of Laser Induced Cumulative Stress for Efficient Processing of Fused Silica
Cross section of part of a 2-layer Fresnel lens written with a Bessel beam using halfscan technique at power of 90 mW. Diameter of Fresnel lens is 2 mm and thickness of each layer is 100 μm. The dotted line is the centre of the Fresnel lens.
