SCATMECH > Classes and Functions > Surface Scattering Models > Rayleigh_Instrument_BRDF_Model

class Rayleigh_Instrument_BRDF_Model

The class Rayleigh_Instrument_BRDF_Model calculates the effective BRDF for non-diffusely scattering sample measured with an instrument having a field of view, lFOV, when the sample is surrounded by air.

Diagram showing the components contributing to the effective BRDF of a sample surrounded by air.

Parameters:

Parameter Data Type Description Default
lambda double Wavelength of the light in vacuum [µm].
(Inherited from BRDF_Model.)		 0.532
type int Indicates whether the light is incident from above the substrate or from within the substrate and whether the scattering is evaluated in reflection or transmission. The choices are:
0 : Light is incident from the above the substrate, and scattering is evaluated in reflection.
1 : Light is incident from the above the substrate, and scattering is evaluated in transmission.
2 : Light is incident from the within the substrate, and scattering is evaluated in reflection.
3 : Light is incident from the within the substrate, and scattering is evaluated in transmission.
For 1, 2, and 3, the substrate must be non-absorbing.
Rayleigh_Instrument_BRDF_Model only supports type=0.
(Inherited from BRDF_Model).		 0
substrate dielectric_function The optical constants of the substrate, expressed as a complex number (n,k) or, optionally, as a function of wavelength.
(Inherited from BRDF_Model.)		 (4.05,0.05)
stack StackModel_Ptr Description of any stack of films deposited on the substrate. No_StackModel
field_of_view double The field of view at the sample [µm]. 1000
air dielectric_function The optical constants of the substrate, expressed as a complex number (n,k) or, optionally, as a function of wavelength.
(Inherited from BRDF_Model.)		 (1+2784E-7,0)
number_density double The volume number density [µm-3] of the molecules surrounding the sample. This parameter can be obtained by the ideal gas law and depends upon temperature and pressure. 2.51E-7

See also:

SCATMECH Home,   Conventions,   Instrument_BRDF_Model,   dielectric_stack

T.A. Germer and C.C. Asmail, C. C., "A goniometric optical scatter instrument for bidirectional reflectance distribution function measurements with out-of-plane and polarimetry capabilities," in Scattering and Surface Roughness, Z.-H. Gu and A.A. Maradudin, Editors, Proc. SPIE 3141, 220-231 (1997).

C. Asmail, J. Hsia, A. Parr, and J. Hoeft, "Rayleigh scattering limits for low-level bidirectional reflectance distribution function measurements," Appl. Opt. 33, 6084-6091 (1994).

C. Asmail, A. Parr, and J. Hsia, "Rayleigh scattering limits for low-level bidirectional reflectance distribution function measurements: corrigendum," Appl. Opt. 38, 6027-6028 (1999).

Include file:

#include "rayinst.h"

Source code:

rayinst.cpp

Definition of public elements:

Include file:

#include "rayinst.h"

Source code:

rayinst.cpp

Definition of public elements:

class Rayleigh_Instrument_BRDF_Model
: public Instrument_BRDF_Model
{
};

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Current SCATMECH version: 7.22 (April 2021)