Over the last decade, femtosecond lasers have been used extensively for the fabrication of optical elements via direct
writing and in combination with chemical etching. These processes have been an enabling technology for manufacturing
a variety of devices such as waveguides, fluidic channels, and mechanical components.
Here, we present high quality micro-scale optical components buried inside various glass substrates such as soda-lime
glass or fused silica. These components consist of high-precision, simple patterns with tubular shapes. Typical diameters
range from a few microns to one hundred microns. With the aid of high-bandwidth, high acceleration flexure stages, we
achieve highly symmetric pattern geometries, which are particularly important for achieving homogeneous stress
distribution within the substrate.
We model the optical properties of these structures using beam propagation simulation techniques and experimentally
demonstrate that such components can be used as cost-effective, low-numerical aperture lenses. Additionally, we
investigate their capability for studying the stress-distribution induced by the laser-affected zones and possible related