Near infrared laser diode

J. Hicks, D. Andrews-Wilberforce, and G. Patonay, A near-infrared laser diode excitation source for an SLM 8000CI luorometer, Anal. Instrum. 19,29-47 (1990). 

G. Patonay, J.-M. Zen, andT. Czuppon, Near-infrared laser diodes in monitoring applications, SPIE s International Symposium OE/Environmental and Process Monitoring Technologies, 1637, 142-150 (1992). 

E. Unger and G. Patonay, Near-infrared laser diode intracavity absorption specttometry, Anal. Chem. 61, 1425-1427 (1989). 

The near-infrared laser diode has a maximum laser output of 100 mW. The short laser pulse widths utilized, the low laser power levels required, the absorption of the laser pulse by the polymer and dye, and the long elapsed time between laser pulses combine to prevent the experimenter from depositing any significant amount of heat at the tissue surface, which may affect later laboratory analysis. The Class IV UV cutting laser, on the contrary, ablates the cells in the vicinity of the laser pulse. The UV cutting tool is designed for microdissection of larger... 

Allen, T.J. and Beard, P.C. (2005) Pulsed near-infrared laser diode excitation system for biomedical photoacoustic imaging. Optics Letters, 31, 3462-4. 

In the last years it became possible to manufacture silicon SPADs in standard epitaxial processes as they are used for high-speed CMOS devices [117, 245, 246, 354, 424, 459]. The diodes are characterised by a small thickness of the depletion region. The thin depletion region results in a relatively low breakdown voltage, high time resolution, and low dark count rate. The drawback of the thin depletion region is a reduced quantum efficiency in the near infrared. Laser pulses recorded with an id 100-20 SPAD detector of id Quantique [245] and an SPC-144 TCSPC module of Becker Hickl are shown in Fig. 6.57. 

A diode, or semiconductor, laser operates in the near-infrared and into the visible region of the spectmm. Like the mby and Nd YAG lasers it is a solid state laser but the mechanism involved is quite different. 

Lasers having wavelengths ranging from the deep uv to the near infrared have been used in Raman spectroscopy. In industrial laboratories, the most common laser is the Nd YAG operating at 1.06 pm. Increasingly, diode lasers or other lasers operating in the 750—785-nm region are encountered. These... 

For the visible and near-ultraviolet portions of the spectmm, tunable dye lasers have commonly been used as the light source, although they are being replaced in many appHcation by tunable soHd-state lasers, eg, titanium-doped sapphire. Optical parametric oscillators are also developing as useful spectroscopic sources. In the infrared, tunable laser semiconductor diodes have been employed. The tunable diode lasers which contain lead salts have been employed for remote monitoring of poUutant species. Needs for infrared spectroscopy provide an impetus for continued development of tunable infrared lasers (see Infrared technology and RAMAN spectroscopy). 

There are, however, many approaches to DNA sequencing, and even some recent instruments such as the sequencer made by LI-COR [28] do not use a CCD. The latter uses instead a very-low-noise silicon avalanche photodetector to excite near infrared-emitting dyes. The source is a laser diode emitting at 785 nm. It is a compact system that can be mounted on a focusing stage with confocal optics and it is meant for small laboratories that do not have HTS requirements. 

Since the advent of the semi-conducting diode lasers there has been much interest in compounds that absorb in the near-infrared region of the spectrum. This is because they can be used to absorb the energy of the laser at a specific wavelength of the... 

In a laser diode, population inversion of charge carriers in a semiconductor is achieved by a very high electric field across a pn junction in gallium arsenide. Most laser diodes operate at red and near-infrared wavelengths (680-1 550 nm). 

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