Multiple Laser Sources Research Articles

Coherent anti‐stokes Raman scattering microscopy: A biological review

Microscopic imaging of cells and tissues are generated by the interaction of light with either the sample itself or contrast agents that label the sample. Most contrast agents, however, alter the cell in order to introduce molecular labels, complicating live cell imaging. The interaction of light from multiple laser sources has given rise to microscopy, based on Raman scattering or vibrational resonance, which demonstrates selectivity to specific chemical bonds while imaging unmodified live cells. Here, we discuss the nonlinear optical technique of coherent anti-Stokes Raman scattering (CARS) microscopy, its instrumentation, and its status in live cell imaging.

Multiple wavelength time-of-flight sensor based on time-correlated single-photon counting

This article describes a time-of-flight sensor based on multiple pulsed laser sources which utilizes time-correlated single-photon counting. The sensor has demonstrated good performance at ranges of up to 17 km in daylight conditions. Analysis techniques were developed to examine the returns from targets containing more than one scattering surface.

Investigation into the accuracy of a proposed laser diode based multilateration machine tool calibration system

Geometric and thermal calibration of CNC machine tools is required in modern machine shops with volumetric accuracy assessment becoming the standard machine tool qualification in many industries. Laser interferometry is a popular method of measuring the errors but this, and other alternatives, tend to be expensive, time consuming or both. This paper investigates the feasibility of using a laser diode based system that capitalises on the low cost nature of the diode to provide multiple laser sources for fast error measurement using multilateration. Laser diode module technology enables improved wavelength stability and spectral linewidth which are important factors for laser interferometry. With more than three laser sources, the set-up process can be greatly simplified while providing flexibility in the location of the laser sources improving the accuracy of the system.

Polarization-independent silica-on-silicon Mach-Zehnder interferometers

The birefringence induced by compressive strain in silica waveguides on silicon substrates is compensated with a silicon nitride patch placed below the core. We demonstrate Mach-Zehnder interferometers with polarization-independent spectral response, including a compensated Mach-Zehnder interferometer suitable for stabilization of multiple laser sources in a dense wavelength division multiplexed fiber optic communication network. Furthermore, we show how silicon nitride can also be used to compensate polarization dependent losses. Polarization independence achieved with a silicon nitride patch is applicable to a wide variety of other devices such as arrayed waveguide grating multiplexers and Bragg reflectors. >