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Electrochromic (EC) nickel oxide (NiO) films were prepared either by plasma oxidation of vacuum-deposited nickel-carbon (Ni–C) composite films or by thermal oxidation of those films. EC properties of the NiO films were measured by cyclic voltammetry in 1 M KOH. The degree of electrochromism in the NiO films depended not only on the Ni-to-C (Ni/C) ratio in the Ni–C films but also on the oxidation conditions of the Ni–C films. The NiO film with a Ni/C ratio of ∼0.6 showed the longest cycling ability among the films with three different Ni/C ratios (∼0.3, ∼0.6 and ∼1.2). The NiO film thermally oxidized at 500° C showed smaller transmission modulation and passed charge density than the plasma oxidized film, but could be electrochemically switched for more than 5000 cycles without serious residual coloration.

The microfocusing of 200 keV X-rays with a sputtered-sliced zone plate (ss-FZP) was performed at the wiggler beamline (BL08W, Station A) at SPring-8. The ss-FZP used was the same as that used in the 100 keV X-ray focusing experiment previously reported. The minimum focal spot size attained for the first-order focal beam was ~5 µm with a focal distance of 1720 mm at a photon energy of 200 keV.

The substrate dependence of the laser damage threshold of high-reflector (HR) coatings (Sc2O3/MgF2 HRs and Sc2O3/SiO2 HRs) for a 355-nm pulsed laser was examined. A correlation between the thermal expansion coefficient of the substrates and the damage thresholds was observed: HRs on substrates with larger thermal expansion coefficient (BK-7, sapphire) had higher threshold than those on substrates with a smaller coefficient (fused silica).

The experimental results of the laser-induced damage thresholds of Sc2O3/MgF2 high-reflector (HR) coatings for an UV (355-nm, 0.4-ns) pulsed laser have been shown. The deposition parameters have been optimized by use of 5-layer semitransparent coatings, with the distribution of the standing-wave electric-field being similar to that of the HR coatings. For the 5-layer coatings, their threshold values were found to depend on the deposition parameters and the absorption; the coatings with low absorption had high damage threshold. Based on these results, the HR coatings were fabricated on fused silica, BK7 and sapphire substrates, and their thresholds have been measured. The highest average threshold on each substrate have been 3.5, 4.2 and 3.8 J/cm2, respectively.

The laser damage thresholds of various types of antireflection (AR) coatings for an UV (355-nm) laser system were measured. Among them, the coatings consisting of two low-index materials, SiO2 and MgF2, had the highest average thresholds: 2.1 J/cm2 fused silica substrates and 2.6 J/cm2 sapphire substrates. The SiO2/MgF2 coating is hopeful for UV laser component.