Physical Optics Propagation (POP) Results

Physical Optics Propagation Data. For important details see the "About Physical Optics Propagation" section of the Help Files.

To use this operand, first define the settings on the POP analysis feature as desired, then press Save on the settings box. The operand will return data based upon the selected settings.

If Surf is zero, then the saved ending surface number will be used; otherwise, the specified surface will be used as the ending surface. If Wave is zero, then the saved wavelength number will be used; otherwise, the specified wavelength number will be used. If Field is zero, then the saved field number will be used; otherwise, the specified field number will be used.

Data determines what data the POP feature will compute and return as follows:

0: The total fiber coupling. This is the product of the system efficiency and the receiver efficiency.

1: The system efficiency for fiber coupling.

2: The receiver efficiency for fiber coupling.

3: The total power.

4: The peak irradiance.

5, 6, 7: The pilot beam position, Rayleigh range, beam waist (x).

8, 9, 10: The pilot beam position, Rayleigh range, beam waist (y).

11, 12, 13: The local X, Y, Z coordinates of the center of the beam array on the end surface (this is a reference point and is not related to the amplitude of the beam).

21, 22: The X, Y coordinates of the centroid of the intensity distribution in local coordinates relative to the center of the beam. The orientation of the X/Y axes for this result are not necessarily the same as the orientation of the end surface.

23, 24, 25, 26: The X, Y beam width and the X, Y M-squared values, respectively. For data 23, 24 with default Xtr1 value set to 0 beam widths are calculated in the lab coordinate system. When Xtr1 value set to 1 beam widths are calculated in the direction of its principle axes. Note when calculating M-squared value for asymmetric beams, the "Separate X, Y" must be checked when clicking the "Save" button in the POP analysis setting dialog. See "Beam with and M-squared".

27: The square root of second moment of the beam for x ², θ _x ², xθ _x, and xθ _y for Xtr1 values 0, 1, 2, and 3, respectively.

28: The square root of second moment of the beam for y ², θ _y ², yθ _y, and yθ _x for Xtr1 values 0, 1, 2, and 3, respectively.

29: The square root of second moment of the beam for xy and θ _x θ _y for Xtr1 values 0 and 1, respectively.

The angular distributions in 27, 28 and 29 have no unit. They are calculated from the direction vector.

30, 31, 32: The mean, RMS and PTV irradiance variation, respectively, of the non-zero amplitude portion of the beam. These operands should only be used when the beam has nearly uniform irradiance and has just been clipped by a surface aperture.

33, 34, 35: The mean, RMS and PTV phase variation in radians, respectively, of the non-zero amplitude portion of the beam. These operands should only be used when the beam has nearly uniform irradiance and has just been clipped by a surface aperture.

40, 41, 42: The fraction of the total power enclosed within a circle of radius specified by the Xtr1 value in lens units, referenced to the beam centroid (40), chief ray (41), or surface vertex (42).

50, 51, 52: The radius in lens units of the circle at which the fraction of the total power enclosed is equal to the value specified by the Xtr1 value. The circle is centered on the beam centroid (50), chief ray (51), or surface vertex (52).

60, 61, 62, 63: The fiber coupling receiver efficiency amplitude and phase in radians for the Ex field (60 and 61) and the Ey field (62 and 63). These values do not consider system efficiency (see Data type 1 above). Data inputs 60-63 request a polarized POP calculation, but if the input beam is unpolarized, the field coupling efficiency amplitudes and phases are not physically well-defined.  Therefore, values of 0.0 will be returned if the input beam is unpolarized.

Undefined Data values will return 0.

The Xtr1 and Xtr2 values are only used by selected data numbers which are reserved for future expansion of this feature.

If adjacent POPD operands all have the same Surf, Wave, Field, Xtr1, and Xtr2 values, then the POP analysis is done just once and all data returned at one time. Note the POPD operands must be on adjacent rows in the MFE for this efficiency to be implemented.

Physical Optics Propagation Data. For important details see the section on "Physical Optics Propagation".

To use this operand, first define the settings on the POP analysis feature as desired, then press

Save on the settings box. The operand will return data based upon the selected settings.

If Surf is zero, then the saved ending surface number will be used; otherwise, the specified surface will be used as the ending surface. If Wave is zero, then the saved wavelength number will be used; otherwise, the specified wavelength number will be used. If Field is zero, then the saved field number will be used; otherwise, the specified field number will be used.

Data determines what data the POP feature will compute and return as follows:

0, 1, 2: The total (Ex + Ey), Ex only, or Ey only Irradiance.

3, 4, 5, 6: Ex-real, Ex-Imaginary, Ey-real, Ey-imaginary.

7, 8: Ex, Ey phase in radians. Undefined Data values will return 0.

The Pix# refers to the desired pixel of the beam. The pixel number is greater than or equal to zero, and less than nx*ny, where nx and ny are the number of columns and rows, respectively. The pixel number is generally defined as p = x + y*nx where x is the integer row number and y is the integer column number, and 0 <= x < nx and 0 <= y < ny.

If adjacent POPI operands all have the same Surf, Wave, and Field values, then the POP analysis is done just once and all data returned at one time. Note the POPI operands must be on adjacent rows in the MFE for this efficiency to be implemented.