Light angle-resolved and total integral scattering (ARS and TIS) have been used for several decades to probe surface roughness and heterogeneities in optical multilayers and substrates. We present a summary of results reached in laser metrology techniques in our Institute. Elaboration of the optical surface finish technology requires non-destructive sensitive measurement methods subsequent development. Need optical surfaces for precision quantum electronics devices are usually composed of irregularities smaller than 1 nm "high" with "slope" of low gradient of perhaps 0,001 rad relative to the mean surface and destructive layer thickness about tens of nanometres. There are described application of ARS method and automatically device, based on this method for testing optically transparent surfaces by scattering indicatrix analysing. We discuss the problem: how it can measure surfaces roughness of inside scattering materials substrates and separate of surface roughness and substrates material heterogeneity effects. We touched up the questions: how surface rms-roughness of substrates correlates with scattering of mirrors and how smooth surfaces of substrates correlate with back specula scattering of ion-sputtering on these substrates mirrors. In some cases of our researches we compared the light scattering measurement results with the results of atomic force microscope (AFM) and X-rays scattering (XRS) measurement methods.
Ion beam optical coatings based on titanium, tantalum and silicon oxides find wide application in visible and near IR lasers since they allow production of mirrors with a high coefficient of reflection as well as provide high laser damage thresholds. This paper reports on development of the coatings with low absorption and scattering and high coefficient of reflection (99.98%) at 632 nm for circular polarization and an angle of bean incidence of 45 degree(s) as well as on the protective antireflection coatings on BBO crystals and silicate glass at 1064 nm with high laser damage thresholds (15 . . .20 J/cm2). Absorption, scattering and loss in the mirrors as well as laser damage thresholds of the protective antireflection coatings have been measured.
Zeeman laser gyros have found wide application. Contrary to ordinary laser gyros operating at linear polarization of emission, Zeeman gyros require the use of mirrors having low losses in both polarizations at oblique incidence of laser emission and minimum phase anisotropy. High-reflection TiO2 and SiO2 mirrors at 632 nm for such gyros have been produced by ion-beam sputtering for the angle of beam incidence of 45 +/- 1 degree. The characteristics of the optical coatings have been measured by laser modulated photothermal radiometry, photothermal deflection technique, total integrated scattering measurements, the resonance method using the ring cavity, and the ellipsometrical method. The obtained results have allowed optimization of the coating deposition processes. For the 23...25-layer mirrors the following results have been obtained: (i)absorption - 30...70 ppm; (ii) total integrated scattering - 50...70 ppm; (iii) total loss - 250...300 ppm in circular polarization; (iv) phase anisotropy of p and s components of emission - 0.03...0.05 rad. The produced mirrors have allowed realization of compact Zeeman laser gyros with a lock-in about 100...200 Hz and an accuracy of angular velocity measurement at a level of 0.1 degree/h. The ways to reduce the ion-beam mirror losses are discussed.
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