Low cost dry ice blaster for in situ cleaning of sensitive optics

This paper presents a specialized dry ice blaster (DIB) designed for in situ cleaning of sensitive optical components. The DIB can be fabricated with fused deposition modeling (FDM) 3D printers. Results are presented for cleaning performed on highly contaminated laser cutter optics, unprotected gold off-axis parabolic (OAP) mirrors in Terahertz (THz) spectrometers, and dielectric mirrors. THz spectra indicate that DIB cleaning enabled small improvements in the peak THz electric field, while visibly cleaning the OAPs in the spectrometer. Tests with IR light showed the DIB is very effective in restoring the reflectivity of contaminated mirrors while avoiding causing permanent damage.