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how to create barcode in vb.net 2008 Dark Current and Noise Current in Software
Dark Current and Noise Current Recognizing Code 128C In None Using Barcode Control SDK for Software Control to generate, create, read, scan barcode image in Software applications. Code 128C Printer In None Using Barcode generator for Software Control to generate, create ANSI/AIM Code 128 image in Software applications. As can be seen from the noise equation (Equation 2), the total APD dark current (and the corresponding spectral noise current) is only meaningful when specified at a given operating gain. Dark current at M = 1 is dominated by surface current, and may be significantly less than IDB M Since APD dark and spectral noise currents are a strong function of APD gain, these should be specified at a stated responsivity level. An example of a typically correct specification for diode dark current and noise current in this case, for an InGaAs APD is as follows: ID (R = 9.0A/W) = 10 nA (max), M = 10 iN (R = 6.0 A/W, 1 MHz, 1 Hz BW) = 0.8 pA/ Hz (max), M>5 Scan Code 128 Code Set A In None Using Barcode reader for Software Control to read, scan read, scan image in Software applications. Code 128B Drawer In C#.NET Using Barcode generation for VS .NET Control to generate, create Code 128A image in VS .NET applications. Excess Noise Factor
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Painting GTIN  12 In None Using Barcode generation for Software Control to generate, create UPC A image in Software applications. EAN / UCC  13 Maker In None Using Barcode printer for Software Control to generate, create EAN / UCC  13 image in Software applications. exceeds that which would be expected from a noiseless multiplier on the basis of Poissonian statistics (shot noise) alone. The excess noise factor is a function of the carrier ionization ratio, k, where (k) is usually defined as the ratio of the hole to electron ionization probabilities. The excess noise factor may be calculated using the model developed by McIntyre (3), which considers the statistical nature of avalanche multiplication. The excess noise factor is given by: F = kEFF M + (1 kEFF)(1 1/M) (4) Bar Code Generation In None Using Barcode generator for Software Control to generate, create bar code image in Software applications. Printing EAN13 In None Using Barcode creator for Software Control to generate, create EAN / UCC  13 image in Software applications. Therefore, the lower the values of k and M, the lower the excess noise factor. The effective k factor (kEFF) for an APD can be measured experimentally by fitting the McIntyre formula to the measured dependence of the excess noise factor on gain. This is best done under illuminated conditions. It may also be theoretically calculated from the carrier ionization coefficients and the electric field profile of the APD structure. The ionization ratio k is a strong function of the electric field across the APD structure, and takes its lowest value at low electric fields (only in silicon). Since the electric field profile depends upon the doping profile, the k factor is also a function of the doping profile. Depending on the APD structure, the electric field profile traversed by a photogenerated carrier and subsequent avalancheionized carriers may therefore vary according to photon absorption depth. For indirect band gap semiconductors such as silicon, the absorption coefficient varies slowly at the longer wavelengths, and the mean absorption depth is therefore a function of wavelength. The value of kEFF, and gain, M, for a silicon APD is thus a function of wavelength for some doping profiles. The McIntyre formula can be approximated for a k < 0.1 and M > 20 without significant loss of accuracy as: F=2+k M (5) Bookland EAN Generator In None Using Barcode creator for Software Control to generate, create Bookland EAN image in Software applications. Making Matrix 2D Barcode In Visual Basic .NET Using Barcode generation for .NET Control to generate, create Matrix Barcode image in Visual Studio .NET applications. Also often quoted by APD manufacturers is an empirical formula used to calculate the excess noise factor, given as: F = Mx (6) ANSI/AIM Code 128 Decoder In Visual Basic .NET Using Barcode reader for VS .NET Control to read, scan read, scan image in .NET applications. Make UPC  13 In None Using Barcode printer for Online Control to generate, create EAN13 image in Online applications. where the value of X is derived as a lognormal linear fit of measured Fvalues for given values of gain M. This approximation is sufficiently appropriate for many applications, particularly when used with APDs with a high k factor, such as InGaAs and germanium APDs. Table 7.3 provides typical values of k, X, and F for silicon, germanium, and InGaAs APDs. UPCA Generation In Visual C#.NET Using Barcode printer for Visual Studio .NET Control to generate, create GS1  12 image in .NET applications. Code128 Scanner In None Using Barcode reader for Software Control to read, scan read, scan image in Software applications. Industrial Sensors and Control
Decode Data Matrix In None Using Barcode decoder for Software Control to read, scan read, scan image in Software applications. Bar Code Creator In Visual Studio .NET Using Barcode creator for VS .NET Control to generate, create barcode image in VS .NET applications. The silicon APDs have three different values of ionization ration: The SuperLow k (SLiK) APDs used in photon counting modules The highperformance reachthrough structures with k = 0.02 for applications requiring extremely low noise APD and high gain The lowcost silicon epitaxial APD with k = 0.06 ideal for high SNR applications. In germanium and InGaAs APDs, the kvalue is generally quoted at M = 10, which somewhat overestimates F at M < 10 and underestimates F at M > 10.

