Abstract: Aberrations in stimulated emission depletion microscopy are corrected using an adaptive optics approach using a metric which combines both image sharpness and brightness. Light modulators (22,32) are used to perform aberration correction in one or more of the depletion path (10), the excitation path (12), or the emission path from sample to detector.

Abstract: In a method and system for controlling the shape of an optical pulse, the two-dimensional shape of the phase front is controlled using a first control device and the shape of the phase front and the two-dimensional shape of the pulse front is controlled using a second control device. The combined effect on the phase front results in a desired overall phase front control and the second device provides the desired overall pulse front control. This enables the phase front control and pulse front control to be decoupled. Correcting for pulse lengthening of femtosecond laser pulses during focusing by a dispersive lens. The spatially varying phase (72) introduced by the lens can be corrected for by a spatial light modulator like (SLM) a liquid crystal modulator. The spatially varying arrival time at the focus (70) can be compensated for by a deformable mirror (DM). A controller with a feedback loop and pulse characterization in the focus can compensate for the errors introduced by any dispersive focusing means.

Abstract: A method of measuring fluorescence lifetime includes illuminating a sample containing at least one fluorophore with light to excite fluorescence and switching the intensity of the excitation light repeatedly between a first intensity I1 and a second intensity 12. Emitted light caused by fluorescence of the sample is detected and a detected light signal is generated. The detected light signal is switched repeatedly to divide it into first and second portions, and the amount of light detected during each of the first and second portions is measured to obtain a first emitted light value S1 and a second emitted light value S2. The fluorescence lifetime is determined from the first and second emitted light values S1 and S2.

Abstract: Oil-soluble reaction product of an oil-soluble basic alkaline earth metal salt of an organic acid, in particular of an aromatic carboxylic acid and a boron compound, in particular a boric acid. This product has superior detergent, anti-wear and anti-corrosion properties in engine oils.