Measurement of laser intensity inside a femtosecond laser filament is a challenging task. In this work, we suggest a simple way to characterize laser peak intensity inside the filament in air. It is based on the signal ratio measurement of two nitrogen fluorescence lines, namely, 391 nm and 337 nm. Because of distinct excitation mechanisms, the signals of the two fluorescence lines increase wit...

BACKGROUND Height is an important health assessment measure with many applications. In the medical practice and in research settings, height is typically measured with a stadiometer. Although lasers are commonly used by health professionals for measurement including facial imaging, corneal thickness, and limb length, it has not been utilized for measuring height. The purpose of this feasibility...

BACKGROUND AND OBJECTIVES During laser therapy of port wine stain (PWS) birthmarks, regions of persistent perfusion may exist. Immediate retreatment of such regions may improve PWS laser therapeutic outcome. To address this need, we propose use of laser speckle imaging (LSI) to provide real-time, quantitative feedback during laser surgery. Herein, we present in vitro and in vivo data collected ...

This paper presents an overview of the different 3D surface digitization technologies commercially available in the European market. The solutions for 3D surface measurement offered by major European companies can be divided into different groups depending on various characteristics, such as, technology (e.g. laser scanning, white light projection), system construction (e.g. fix, on CMM/robot/a...

Time-of-flight laser radar devices utilizing a single heterostructure semiconductor laser diode as a light source have a measurement spot diameter from a few millimetres to several centimetres depending on the optics and the required optical output power. Inhomogeneities in the reflectivity and surface profile of a target inside the area illuminated by the laser beam can be a source of error in...

The measurement of the ultra-short electron bunch length on the femtosecond time scale constitutes a very challenging problem. In the x-ray free electron laser facilities such as the Linac Coherent Light Source, generation of a sub-ten femtoseconds electron beam with 20pC charge is possible, but direct measurements are very difficult due to the resolution limit of the present diagnostics. We pr...

In this paper we present a multi-loop measurement feedback control scheme to improve atom laser coherence. The first loop (proposed by Thomsen and Wiseman, 2002) aims to cancel the decohering effects of the nonlinear atom-atom interactions via direct measurement feedback. However, there are nonlinear interactions with the optical probe field used in the measurement scheme which may also contrib...