Rib waveguides have been fabricated in pulsed-laser-deposited Ti:sapphire layers using photolithographic patterning and subsequent Ar-beam milling. Fluorescence output powers up to 300 W have been observed from the ribs following excitation by a 3-W multiline argon laser. Mode intensity profiles show high optical confinement and the measured beam propagation factors 2 and 2 of 1.12 and 1.16, re...

We examined five nucleic acid binding fluorescent dyes, propidium iodide, SYBR Green I, YO-PRO-1, TOTO-3, and TO-PRO-3, for nuclear DNA staining, visualized by fluorescence and laser confocal microscopy. The optimal concentration, co-staining of RNA, and bleaching speeds were examined. SYBR Green I and TO-PRO-3 almost preferentially stained the nuclear DNA, and the other dyes co-stained the cyt...

We present a method for measuring the fluorescence from a single molecule hundreds of times without surface immobilization. The approach is based on the use of electroosmosis to repeatedly drive a single target molecule in a fused silica nanochannel through a stationary laser focus. Single molecule fluorescence detected during the transit time through the laser focus is used to repeatedly rever...

Multiphoton laser microscopy is a new, non-invasive technique providing access to the skin at a cellular and subcellular level, which is based both on autofluorescence and fluorescence lifetime imaging. Whereas the former considers fluorescence intensity emitted by epidermal and dermal fluorophores and by the extra-cellular matrix, fluorescence lifetime imaging (FLIM), is generated by the fluor...

A compact and low-weight LIDAR instrument has been developed for laser-induced fluorescence spectroscopy sensing of maize fields. Fluorescence had to be installed on a small industrial drone so that its mass was <2 kg power consumption <5 W. The utilized continuous wave diode laser (405 nm, 150 mW) inducing spectrometer backscattered photons acquisition. For field testing, the quadcopter ...

A new and compact fluorescence biosensor is constructed. The distinguished feature of this setup is the use of an ellipsoidal reflector as an optical collector of the fluorescence light. A traditional collecting lens with numerical aperture of 0.5 can only collect a few percent of the available signal, while the incorporation of the ellipsoidal reflector enables the apparatus to provide a signa...

We describe a high-performance time-resolved fluorescence (HPTRF) spectrometer that dramatically increases the rate at which precise and accurate subnanosecond-resolved fluorescence emission waveforms can be acquired in response to pulsed excitation. The key features of this instrument are an intense (1 μJ/pulse), high-repetition rate (10 kHz), and short (1 ns full width at half maximum) laser ...

Multiphoton imaging has developed into an important technique for in-vivo research in life sciences. With the laser System DermaInspect (JenLab, Germany) laser radiation from a Ti:Sapphire laser is used to generate multiphotonabsorption deep in the human skin in vivo. The resulting autofluorescence radiation arises from endogenous fluorophores such as NAD(P)H, flavines, collagen, elastin, porph...

Today, fluorescence imaging spans wide spectrum in modern biological investigations from molecular to network level at submicron resolution. To take advantage of full potential of advanced fluorescence imaging techniques, it is important to understand some underlying physical principles. This chapter provides a framework to understand basic principles underlying fluorescence, fluorescence micro...

A laser-pump, x-ray probe spectroscopic experiment is described, and the results are shown. The Ga Ka x-ray fluorescence following x-ray absorption, at the Ga K absorption edge was measured, and its increase due to excitation with subpicosecond pulses of laser light at 4.6 eV photon energy was determined. The x-ray absorption, and thus the fluorescence, is increased for about 200 ps after the l...