In this article, we present the drifts phenomena that affect the temporal resolution of a standard synchroscan streak camera and some techniques to correct them in order to enhance the long-term resolution of these cameras. First, we give a comprehensive list of the components of the synchroscan streak camera which are sensitive to temporal and thermal drift: from the trigger circuit to the deflection plate of the tube. The way in which these components make the camera drift is explained and then quantified. A measure of drift realized on two streak cameras at the same time and in the same conditions (the same synchroscan signal) shows that each camera has its own intrinsic and stochastic drift. Second, two techniques to stabilize the camera are then described. The first method stabilizes the phase difference between the synchroscan signal and the deflection plate voltage. The second uses a laser reference trace on the phosphor screen and a digital data processing technique to reach the ultimate stability. The results show that a stabilized camera can be used immediately after it is turned on (due to suppression of the warm-up time) and still has very good temporal resolution even with a long-time exposure (2.4 ps full width at half maximum with a time exposure of 2 h has been achieved). This allows more exploration in the detection of very weak signals.

We describe an experimental setup for time-resolved diffuse optical tomography that uses a seven-channel light guide to transmit scattered light to a streak camera. This setup permits the simultaneous measurement of the time profiles of photons reemitted at different boundary sites of the objects studied. The instrument, its main specifications, and detector-specific data analysis before image reconstruction are described. The instrumentation was tested with phantoms simulating biological tissue, and the absorption and reduced scattering images that were obtained are discussed.

The conventional streak camera (CSC) is an optoelectronic instrument that captures the spatial distribution as a function of time of an ultra high-speed luminous phenomenon with picosecond temporal resolution and a typical spatial resolution of several tens of micrometers. This paper presents two tubeless streak camera architectures called MISC (matrix integrated streak camera) and VISC (vector integrated streak camera), which replicate the functionality of a CSC on a single CMOS chip. The MISC structure consists of a lens, which spreads the photon flux on the surface of a specific pixel array-based (Bi)CMOS sensor. The VISC architecture is based on a sensor featuring a single column of photodetectors, where each element is coupled to a front-end and a multi-sampling and storage unit. In this case the optical objective used in front of the sensor focuses the luminous event on the several tens of micrometers wide photosensitive column. For both architectures, the spatial resolution is linked to the size of the photodetector and the temporal resolution is determined by the bandwidths of the photodetectors and the signal conditioning electronics. The capture of a 6 ns full width at half maximum 532 nm laser pulse is reported for two generations of MISC and a first generation of VISC.

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