SolGel AR coatings from Cleveland Crystals, Inc. offer broadband, ultra damage resistant alternatives to conventional dielectric coatings.  Especially suited to substrates which cannot accept hard dielectric coatings, like KDP and KD*P, SolGel exhibits low reflectance over wide wavelength ranges (see Figure 1, below and Figure 2, right).  While conventional multiple layer dielectric stacks are typically designed to withstand 4 to 6 J/cm² in pulses a few to ten nanoseconds wide, SolGel coatings can handle 40 J/cm² in this pulse regime at 1064 nm and 15 J/cm² at 355 nm. 
     With a net index of refraction near 1.2, SolGel AR coatings provide a near optimal index match to fused silica, BK7, KDP and KD*P.  They also provide a good match to BBO, Ba(NO₃)₂ and other nonlinear materials. 
     SolGel AR coatings improve intra-cavity optics like Pockels cell Q-switches and are standard on Cleveland Crystals' new IMPACT! Pockels cell line.  They are also available on the Series QX and TX lines as well.  Pockels cells with SolGel AR coatings are well suited for use in Ti:Sapphire laser and regenerative amplifier cavities.  For shorter wavelength applications, ask for details about Cleveland Crystals' UV Grade Q-switches. 

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SolGel AR coatings consist of a /4 layer of porous silica.  Although mechanically soft, Cleveland Crystals' engineers have developed hardening techniques for some substrate materials. 
     Hardened SolGel AR coatings help astronomers achieve improved, wide band transmission with less risk to telescope optics up to 300 mm diameter. (technology is being developed to provide coating options for up to 1 meter diameter optics). Unlike conventionally applied coatings, technicians apply SolGel at room temperature and pressure, reducing risk due to thermal shock and handling. 
     Manufacturers of ultraviolet photolithography optics can use SolGel AR coatings to produce reliable, low loss CaF₂ and MgF₂ optical systems.  Reasonably priced and scalable to large volume manufacturing, SolGel AR coatings are easy to remove, usually without polishing, so damaged optics cost less to repair. 
     Nonlinear optics demand highly damage-resistant AR coatings, like Cleveland Crystals' SolGel.  Increasing laser intensity to drive more efficient nonlinear frequency conversion can present design challenges as laser intensity reaches bulk material damage thresholds.  SolGel coatings accept higher intensities than conventional dielectric AR coatings promoting more effective utilization of nonlinear optical media.