Three-beam scanning laser radar microprofilometer

Method of locating the visual axis objectively

“…It consists of a quadrant detector having four channels D (1)(2)(3)(4) ; filters F x (1)(2)(3)(4) and F y (1)(2)(3)(4) selecting the frequencies DF x and DF y ; and phase detectors PD x(1-4) and PD y (1)(2)(3)(4) . At the outputs of the detectors D (1)(2)(3)(4) , as a result of mixing of the frequencies f 0 , f x and f y , the components DF x and DF y appear, which are fed to the signal inputs of the phase detectors PD x(1-4) and PD y (1)(2)(3)(4) . The references of the same frequencies DF x and DF y , are obtained from the drivers controlling the acousto-optical deflectors.…”

“…The references of the same frequencies DF x and DF y , are obtained from the drivers controlling the acousto-optical deflectors. The outputs of the phase detectors, denoted in Figure 3 as phase shifts φ x(1-4) and φ y (1)(2)(3)(4) , are used for computing the surface inclination along the trajectory of scanning. Figure 4 illustrates the above-mentioned three specific cases when the angle a between the axis X and the projection V xy of the line of maximal inclination V on the plane XY is 0° (Figure 4a fovea in the points of measurement A 0 , B 0 , C 0 are h x and h y respectively.…”

“…The beams were frequency shifted, their phase shift corresponding to the path difference and was measured by the output of the detectors “looking” at these neighbouring points on the retina. Configurations of double‐beam and triple‐beam combinations were used. Point‐by‐point relocation of laser beams was implemented along the line trajectories similarly to TV scanning.…”

Reduction of friction and wear by grooves applied on the nanoscale polished surface in boundary lubrication conditions

“…Polishing movements were repeated only a few times to preserve the initial nano-topography of the surface between grooves. Intermediate results were checked by the laser differential phase profilometer [ 10 ] and scanning electron microscope. As a result, ten flat samples with directional grooves had been fabricated.…”