High-throughput in-volume processing in glass with isotropic spatial   resolutions in three dimensions
  We report on fabrication of three dimensional (3D) microstructures in glass with isotropic spatial resolutions. To achieve high throughput fabrication, we expand the focal spot size with a low-numerical-aperture lens, which naturally results in a degraded axial resolution. We solve the problem with simultaneous spatial temporal focusing which leads to an isotropic laser-affected volume with a spatial resolution of ~100 micron. 
Yuanxin Tan, Zhaohui Wang, Wei Chu, Yang Liao, Lingling Qiao, Ya Cheng
physics.optics