Instrumentation streak cameras

Lifetime instruments using a streak camera as a detector provide a better time resolution than those based on the single-photon timing technique. However, streak cameras are quite expensive. In a streak camera, the photoelectrons emitted... 

Y. Tsuchiya, Advances in streak camera instrumentation for the study of biological and physical processes, 1EEEJ. Quan. Elec. QE-20, 1516-1528(1984). 

Fig. 5.1. Decays of the B emission for DMABN/propanol solution at various temperatures (viscosities) ( ) dotted lines, experimental curves solid lines, best fit decays (instrumental response function taken into account), (a) Streak camera data (b) nanosecond resolution decay curves. 

Uhringa W., Zint C. V., Summ P. and Cunin B. (2003), Very high long-term stability synchroscan streak camera . Rev. Sci. Instruments 74, 2646-2653. 

The time resolution of streak cameras (few picoseconds or less) is better than that of single-photon timing instruments, but the dynamic range is smaller (2-3 decades instead of 3-5 decades). 

Fast ccMT >onents in the anisotn y decays are characteristic of many proteins and pq>rides and have been reported in many publications. Picosecond-timescale motions were also reported for tyrosine residues in pro-teins in these studies, a streak camera was used to obtain adequate time resolution. The short correlation rime observed in protons is variable and ranges from 50 to 5(X) ps, with the values being detemuned in part by the rime resolution of the instrument. The shorty correlation time is )proximately equal to that observed for NAIA in w er or fcorrelation times are typically insensitive to protein folding and are not greatly affected ly the viscosity of the solution. 

Visualization of the process of deformation of porous material was effected by means of a pulsed light source (location 7), an IAB-451 shadow instrument, and a high-speed streak camera (HSSC) operating as a slit sweep. The pressure ratio of the incident shock wave in experiments varied between 1,4-4. 

Figure 6. Tempcraiurc dependence of the fluorescence lifetime of BMPC in 1 1 ethanol-methanol. Measurements were carried out at the LENS laboratory of Florence by a picosecond apparatus using as an excitation source (at 380 nm) a dye laser pumped by a frequency-doubled cw Nd-YAG laser and recording the Huorescence time profiles by a streak camera. Since the overall instrumental response time was 75-80 ps, decays with t>200 ps, observed at T<130 K, were analyzed without deconvolution. At 177, 178 and 193 K. the lifetimes were roughly estimated as i=(FWHM -77 ) , where FWHM was the width at half maximum of the decay. Because of the rather high sample absorbances (A .°°2), self absorption may have reduced the lifetimes to some extent.

Over the past decade, Raman spectroscopy has continued to develop as a prime candidate for the next generation of in situ planetary instruments, as it provides definitive stmctural and compositional information of minerals in their natural geological context. A time resolved Raman spectrometer have been developed that uses a streak camera and pulsed miniature microchip laser to provide picosecond time resolution (Blacksberg et al. 2010). The ability to observe the complete time evolution of Raman and fluorescence spectra in minerals makes this technique ideal for exploration of diverse planetary environments, some of which are expected to contain strong, if not overwhelming, fluorescence signatures. In particular, it was found that conventional Raman spectra from fine grained clays. 

The time-resolved PL requires additional instrumentation for capturing the evolution of intensity, such as a fast CCD or a streak camera for detecting very fast transients. However, a simple digital oscilloscope in combination with a pulsed laser may be very useful for measuring the defect-related PL decays in ZnO, which by their very nature are slow and are typically in the range from a few nanoseconds to milliseconds. 

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