The attenuated total reflectance (ATR) hollow waveguides capable of transmitting CO<sub>2</sub> laser have attracted wide research
interest due to its advantages of simple structure, no end reflection, small beam divergence and good transmission modes.
In this work, GeO<sub>2</sub> ATR hollow waveguides for delivery of CO<sub>2</sub> laser radiations were fabricated via an acid-induced
liquid phase deposition (LPD) process. GeO<sub>2</sub> hollow waveguide samples were deposited from acidic aqueous germanate
ion solutions with different GeO<sub>2</sub> concentrations. The morphology, compactness and surface roughness of the
LPD-derived GeO<sub>2</sub> ceramic film were examined by SEM. The crystalline structure of the film sample was determined
using XRD. The low-loss window of the GeO<sub>2</sub> waveguide tube was observed by a FTIR spectrometer. We measured the
transmission loss of the sample for delivery of a 10.6 μm TEM<sub>00</sub>
CO<sub>2</sub> laser beam. The results show that the variations in
loss are consistent with the quality change of the GeO<sub>2</sub> ceramic films grown in solutions at different concentrations.