We report near-optimal tracking of freely diffusing fluorescent particles in a quasi-two-dimensional geometry via photon counting and real-time feedback. We present a quantitative statistical model of our feedback network and find excellent agreement with the experiment. We monitor the motion of a single fluorescent particle with a sensitivity of 15 nm/sqrt Hz while collecting fewer than 5000 f...

Correlated photons can be used to directly measure the detection efficiency of photon counting detectors without any ties to externally calibrated standards. An overview of the history of this technique is given and the paper reviews how to implement it in a practical lab setting. Some of the sources of uncertainty in the technique and how they can be minimized and quantified are discussed. The...

The Neyman type-A and Thomas counting distributions provide a useful description for a broad variety of phenomena from the distribution of larvas on small plots of land to the distribution of galaxies in space. They turn out to provide a good description for the counting of photons generated by multiplied Poisson processes, as long as the time course of the multiplication is short compared with...

Photon-counting light detection and ranging (LiDAR) Ice, Cloud, Land Elevation Satellite-2 (ICESat-2) enables the drafting of global elevation maps. However, vegetation cover, terrain undulation, residual noise in signal photons substantially reduce accuracy ground photon extraction. Existing extraction algorithms do not consider factors influencing extraction, threshold setting lacks a theoret...

Whilst vehicular and industrial contributions to the airborne particulate budget are well explored, the input due to building demolition is relatively unknown. Air quality is of importance to human health, and it is well known that composition of airborne particles can have a significant influence on both chronic and acute health effects. Road dust (RD) was collected before and after the demoli...

OBJECTIVE To estimate standardised hospitalisation ratios (SHR) for chronic lower respiratory diseases among demolition and cement workers in Denmark, 1995-2009. DESIGN This is a population-based register study on data from 'the Occupational Hospitalisation Register'. SHR of chronic obstructive pulmonary disease (COPD) was calculated for both demolition and cement workers. SETTINGS Register...

Efficient photon-counting imaging in low signal photon level is challenging, especially when noise intensive. In this paper, we report a first unit (FSPU) method to rapidly reconstruct depth image from sparse counts with strong robustness. The consists of acquisition strategy and reconstruction strategy. Different statistic properties are exploited quickly distinguish during acquisition. Three ...

Tomographic imaging of a glioma tumor with endogenous fluorescence is demonstrated using a noncontact single-photon counting fan-beam acquisition system interfaced with microCT imaging. The fluorescence from protoporphyrin IX (PpIX) was found to be detectable, and allowed imaging of the tumor from within the cranium, even though the tumor presence was not visible in the microCT image. The combi...

We report on an airborne demonstration of atmospheric oxygen optical depth measurements with an IPDA lidar using a fiber-based laser system and a photon counting detector. Accurate knowledge of atmospheric temperature and pressure is required for NASA's Active Sensing of CO2 Emissions over Nights, Days, and Seasons (ASCENDS) space mission, and climate modeling studies. The lidar uses a doubled ...