Laser diagnostic instruments

Many laser-based droplet diagnostic techniques have evolved from the fields such as spray combustion and spray drying. Phase-Doppler particle analyzer is now recognized as the most successful and advanced diagnostic instrument for spray characterization. Other proven diagnostic techniques include laser velocimetry and... 

The purpose of this paper is to review the use of laser induced fluorescence spectroscopy (LIFS) for studying combustion processes. The study of such processes imposes severe constraints on diagnostic instrumentation. High velocities and temperatures are common, as well as turbulent inhomogeneities, and there is a need to make space and time resolved species concentration and temperature measurements. The development of LIFS has reached the point where it is capable of making significant contributions to experimental combustion studies. 

In addition to DAS, specialized software is also needed for laser diagnostics. Laser signals from the flame are usually captured by a camera, and instrument-specific software is available for controlling the camera. For instance, Han and Mungal [9] employed a MATLAB based in-house software PIVlab to process their PIV images. Goh and Gollahalli [34] used WinSpec to process their OH-PLIF measurements with ICCD camera. 

The industries that support optometry and ophthalmology practices include laser manufacturers, optical diagnostic instruments manufacturers, and lens manufacturers. Lenses are used for diagnosis of vision problems as well as for vision correction. 

Lack of advances in optics has hampered improvements in microscopic imaging. Development of adaptable, inexpensive fiber optics to transmit high-energy femtosecond pulses from mode-locked lasers, custom phase plates, and miniature laser beam scanners for endoscopic microscopy instruments offer the potential for enormous advances in laser scanning microscopy for various applications, including medical diagnostics and surgery. 

Technical improvement in instrumentation such as laser and optics will decrease the instmmentation cost and cause Raman instruments more accessible. The development of table-top SERS equipment and their application to bio-related fields would make SERS nanomaterials more popular in the medical and diagnostic fields. This can be used not only for low-priced research instrument but also for fast screening tools of hazard materials and biomaterials in the street. 

Menon, M. M., and A. Slotwinski, 2004, Novel Doppler Laser Radar for Diagnostics in Fusion Reactors, Review of Scientific Instruments, 75,4100-4102. 

In the next section of this paper, we will focus in more detail on the Implementation of CARS for combustion diagnostics and highlight some of the laser physics problem areas where further improvements would be desirable. Subsequent to that, the status of current spectroscopic research areas in high pressure modelling and electronic resonance CARS will be described. The paper will conclude with some Illustrative field applications including a description of a compact, mobile CARS Instrument designed for practical combustion measurements. 

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