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Optimum material selection for high fluence interference coatings is wavelength dependent (increased bandgap with decreased wavelength) whereas the deposition process depends on pulse length (increased densification with decreased pulse length).

Phase 1 performance ramping of the HAPLS pump laser, a high-energy DPSSL based on Nd:glass, successfully produced 70J at 1053nm from a single aperture and 39J at 527nm using LBO frequency converter running at 3.3Hz repetition rate.

The laser resistance of a transparent conductive layer such as ITO is increased by placement into the low electric field region of a Fabry-Perot multilayer filter.

Investigation of large-aperture laser damage at oblique incidence shows that the damage induced by laser contaminants on HR multilayer coatings depends on the thickness and thermal-mechanical properties of the protective capping materials

We present techniques for measuring the damage performance of a variety of optical components with ps laser pulses, introduce a novel beam diagnostic technique, and explore the sensitivity of damage resistance to laser spot size for the case of high-reflectivity, multilayer dielectric (MLD) mirrors.

The velocity of particles ejected from electron beam evaporated source materials is measured for both hafnia and silica coatings.

Planarizing nodular defects with angle-dependent ion etching and uniform deposition increased the 1064 nm laser resistance of optical interference mirror coatings by greater than 20×.

Computer simulations using finite difference time domain of conical pits show that electric field intensification within multilayer high reflector coatings is minimized when the incident and cone angle are matched.

Femtosecond laser machining is optimized to stabilize nanosecond induced-laser damage and to double the power handling capability of multilayer mirror coatings. Higher per-pulse energy of the machining laser degrades the feature edge quality.

Electric-field modeling provides insight into the laser damage resistance potential of nodular defects. The laser-induced damage threshold for high-reflector coatings is 13x lower at the third harmonic (351 nm) than at the first harmonic (1053 nm) wavelength. Linear and multiphoton absorption increases with decreasing wavelength, leading to a lower-third harmonic laser resistance. Electric-field effects can also be a contributing mechanism to the lower laser resistance with decreasing wavelength. For suitably large inclusions, the nodule behaves as a microlens. The diffraction-limited spot size decreases with wavelength, resulting in an increase in intensity. Comparison of electric-field finite-element simulations illustrates a 3x to 16x greater light intensification at the shorter wavelength.

The laser damage threshold of defects within optical coatings is inversely proportional to defect height. Electric-field modeling shows light intensification as large as 11.8x at normal incidence and as large as 20.4x at oblique incidence.

Roughly 14% of the 7,500 meter-scale optics required for the National Ignition Facility have been fabricated to specification utilizing deterministic processes that were developed for efficient optical finishing of laser glass, BK7, and fused silica.

The large aperture coatings for NIF must maintain high laser damage thresholds, low film stress, high uniformity and precise spectral characteristics. Details of the coating process will be provided as well as results from production.