Near-infrared wavelength

K. Uludag, M. Kohl, J. Steinbrink, H. Obrig, and A. Villringer. Cross talk in the lambert-beer calculation for near-infrared wavelengths estimated by monte carlo simulations. Journal of Biomedical Optics, 7(l) 51-59, 2002. 

Painter, O.J., Husain, A., Scherer, A., O Brien, J.D., Kim, L, and Dapkus, P.D., 1999, Room temperature photonic crystal defect lasers at near-infrared wavelengths in InGaAsP, J. Lightwave Technol. 17(ll) 2082-2088. 

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). 

Measurements of the magnetic susceptibility (58) of the cobalt enzyme (Table 5) show that the metal ion is bound as high-spin Co (II). The intensity of the visible absorption makes an octahedral coordination, as well as tetragonal distortions thereof, very unlikely. In the combination with CN, the Co(II) enzyme exhibits the spectral features of tetrahedral model complexes with regard to intensity as well as structure both in the visible and the near-infrared wavelength regions (Fig. 8). The width of the near-infrared band (cf. 20) indicates that the deviation... 

Troy TL, Thennadil SN. Optical properties of human skin in the near infrared wavelength range of 1000 to 2200 nm. Journal of Biomedical Optics 2001, 6, 167-176. 

Windham, W. R., Park, B., Lawrence, K. C., Buhr, R. J. and Smith, D. P. (2002) Selection of visible/near infrared wavelengths for characterising fecal and ingesta contamination of poultry carcasses, Proceedings of the 10th International Conference on Near-Infrared Spectroscopy (A. M. C. Davies and R. K. Cho, eds), Korea, 2001. pp. 453-6. 

Despite all these disadvantages, the ease of production of 71-Si and the facts that the room temperature PL is very efficient (1-10% external quantum efficiency)26 46 and that it is tunable through blue to near infrared wavelengths have led to impressive efforts to produce practical room-temperature devices. The latest red... 

Masse, A., Pringault, O., and de Wit, R. (2002) Experimental study of interactions between purple and green sulfur bacteria in sandy sediments exposed to illumination deprived of near-infrared wavelengths. Appl. Environ. Microbiol. 68, 2972-2981. 

The transmittance and reflectance spectra of an undoped AP-CVD ZnO film and of a doped AP-CVD ZnO Al film are shown in Fig. 6.40. While the transmittance of the undoped film stays over 80% along the whole visible range, the transmittance of the doped film displays a pronounced drop in the near-infrared wavelength range. The drop corresponds to a minimum in the reflectance curve, as well as to a maximum (peak) in the absorbance curve. This occurs close to the so-called plasma frequency. These effects are due to free carrier absorption. When N is increased, the plasma frequency is shifted towards shorter wavelengths, and the drop in optical transmittance becomes more pronounced. This is illustrated for the case of LP-CVD ZnO.B films in... 

Hubble Space Telescope (HST) a 2.4m mirror-diameter space telescope operating at ultraviolet, optical, and near-infrared wavelengths, operated by NASA and ESA. The HST has a versatile suite of instruments and has been serviced and upgraded several times by astronauts. 

Figure 5.2 Background scattered from silver particles is 10-fold lower at near-infrared wavelengths. (A) Emission bandpass transmittance spectra show the tested wavelength ranges. (B) Relative signal intensities from background scatter are shown for the five different tested wavelengfos.

Earth-based observations made in 1991 and 1992 made in near-infrared wavelengths with the United Kingdom Infrared Telescope Facility on Mauna Kea, Hawaii showed evidence of carbon monoxide and carbon dioxide ices on Triton s surface as well as those of nitrogen and methane. They confirmed the 391°F temperature of Triton s surface and found that there is less than 10% carbon monoxide ice dissolved in the nitrogen ice on Triton s surface. 

Another task often required is the determination of the water content. Quantification of moisture in hard gelan-tin capsules was described by Berntsson, Zackrisson, and Oestling who discussed its importance in monitoring for at-line process control. ° A sparse MLR calibration model with three optimized near-infrared wavelengths yielded an absolute prediction error of... 

The rate of detected pulses equals the rate of photons striking the photocathode times Q. In other words, Q is the fraction of photons that ejects photoelectrons and results in an output pulse. The dark signal results from thermal ejection of electrons from the photocathode. Since Raman spectrometers often operate in the red and near infrared wavelength regions, the work function of the photocathode surface must be quite low. This small work function makes it difficult to prevent dark electron generation. Photon counting... 

In Raman spectroscopy, usually, both the excitation and signal light beams are in visible or near-infrared wavelengths. Therefore, silica-glass flbers, which are commonly used in optical communications, are basically applicable as a flexible... 

Figure 15.2 Absorption spectra of hemoglobin compounds at the visible and near-infrared wavelengths. (From [4] copyright 1994 IEEE, with permission.)... 

The real part n-K of the refractive index for all coals, as reported by all researchers, is between 1.5 and 2.1 within the spectral range of 1 to 20 pm. The imaginary part fcx, however, shows a larger variation (and higher uncertainty), as the reported values are between 0.01 and 1.2. For anthracite coal, for example, Blokh [230] reported kx values close to 0.9 at near infrared wavelengths within the visible spectrum, however, the values are closer to 0.1. For bituminous coals, k is constant at about 0.3 up to 6 pm and then increases linearly with the wavelength. These fix and kx values are plotted in Fig. 7.26. 

Figure 9.8. HTRS curves of x-Co(py)2a, in the visible and near-infrared wavelength region (15).

Since the Beckman DK-2A speciroreflectometer is capable of recording the sample spectra in the near-infrared wavelength region, the HTRS curves... 

Near Infrared. Wavelength range from about 750 nm to 3 pm. Optical Parametric Oscillator. Uses nonlinear optical effects in a crystal to split the pump beam into two coherent output beams of tuneable wavelength. The sum of the reciprocal output wavelengths is equal to the reciprocal input wavelength. 

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