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Attenuation coefficients are used to quantify different media according to how strongly the transmitted ultrasound amplitude decreases as a function of frequency. The attenuation coefficient ( α {\displaystyle \alpha } ) can be used to determine total attenuation in dB in the medium using the following formula:
In a properly configured microscope, ... The magnitude is known as the Modulation Transfer Function ... giving a plot of attenuation vs. frequency. The NTSC3.58 ...
The spectral hemispherical attenuation coefficient in frequency and spectral ... Note that in logarithmic units such as dB, the attenuation is a linear function of ...
An electromagnetic wave propagating in the +z-direction is conventionally described by the equation: (,) = [()], where E 0 is a vector in the x-y plane, with the units of an electric field (the vector is in general a complex vector, to allow for all possible polarizations and phases);
An X-ray microscope uses electromagnetic radiation in the soft X-ray band to produce images of very small objects. Unlike visible light , X-rays do not reflect or refract easily, and they are invisible to the human eye.
For instance, high intensity might or might not indicate the presence of an atom column in that precise location (see simulation). The relationship between the exit wave and the image wave is a highly nonlinear one and is a function of the aberrations of the microscope. It is described by the contrast transfer function.
By virtue of the linearity property of optical non-coherent imaging systems, i.e., . Image(Object 1 + Object 2) = Image(Object 1) + Image(Object 2). the image of an object in a microscope or telescope as a non-coherent imaging system can be computed by expressing the object-plane field as a weighted sum of 2D impulse functions, and then expressing the image plane field as a weighted sum of the ...
A fluorescence microscope is an optical microscope that uses fluorescence instead of, or in addition to, scattering, reflection, and attenuation or absorption, to study the properties of organic or inorganic substances.