Encircled Energy (optimization operands by category)

Diffraction Encircled Energy (distance). This operand computes the distance to the fraction of diffraction encircled, ensquared, x only, or y only (enslitted) energy defined by Frac. For focal mode, the units are micrometers. For afocal mode, the units are afocal mode units. The other parameters are:

Samp: The pupil sampling, where 1 yields 32 x 32, 2 yields 64 x 64 etc.

Wave: The wavelength number to use (use 0 for polychromatic).

Field: The field number.

Type: 1 for encircled, 2 for x only, 3 for y only, and 4 for ensquared.

Refp: The reference point/algorithm to use. For FFT encircled energy, use Refp = 0 for chief ray, 1 for centroid, and 2 for vertex. For Huygens encircled energy, use Refp = 3 for chief ray, 4 for centroid, and 5 for vertex. When using the Huygens method, I Samp refers to the Huygens image sampling (1 for 32 x 32, 2 for 64 x 64, etc.) and I Delta refers to the Huygens image delta. For a detailed description of the Huygens image sampling and image delta, see "Encircled Energy".

If the sampling is too low, the radius returned is 1e+10. See also DENF, GENC and XENC. In order to identify the Diffraction Encircled Energy at the vertex using DENF and DENC need to check with the Image Delta value in the Frac input. As we have Maximum Distance or Image Delta inputs in Diffraction Encircled Energy. By using Maximum Distance or Image Delta, we can identify the peak at some radius. At first, by knowing the peak and radius of vertex in Diffraction Encircled Energy Analysis. Then use this Image delta in DENC and DENF to correct value of Distance and Fraction of energy vs Distance for Vertex as well.

Diffraction Encircled Energy (fraction). This operand computes the fraction of diffraction encircled, ensquared, x only, or y only (enslitted) energy at a given distance from the reference point defined by Dist. For focal mode, the distance units are micrometers. For afocal mode, the distance units are afocal mode units.

The options and settings are identical to DENC, except Dist, which here is used as the distance at which the fraction of energy is desired. See also DENC, GENC, GENF, and XENC.

If the Dist value defined is beyond the point where the encircled energy is very close to 100%, the fraction returned is 1e+10; this is done for optimization efficiency.

Edge Response Function Position. This operand computes the x or y position of the point at which the edge response function reaches a certain relative value. For details on the edge response function calculation, see "Geometric Line/Edge Spread". The Sampling value is 1 for

32x32, 2 for 64x64, etc. Wave is the wavelength number or 0 for polychromatic. Field is the field number. Type determines that data to be returned. If Type is 0 or 1, the x position (for edges parallel to the local y axis) or y position (for edges parallel to the local x axis) relative to the chief ray in lens units is returned. If Wave is zero, the primary wavelength chief ray is the reference point. If Type is 2 or 3, the x or y position in lens units relative to the surface vertex is returned. Fraction is the relative value of the edge response curve, and must be between 0.01 and 0.99. Max Radius is the maximum radial size of the integration window in micrometers. If Max Radius is zero a default value is used, and this is the recommended setting in most cases.

Note that the edge response function is normally defined with the "bright" side of the edge being on the + side of the integration coordinate, which means the edge response goes to 1 as the coordinate becomes more positive. To compute results for the reversed edge orientation, with the bright side on the negative side of the coordinate, use the value (1-fraction) instead of (fraction). For example, to get the 80% response coordinate for a reversed edge, use Fraction = 0.20.

If afocal mode is used, all returned values are in afocal analysis units.

Geometric Encircled Energy (distance). This operand computes the distance to the fraction of geometric encircled, ensquared, x only, or y only (enslitted) energy defined by Frac. For focal mode, the units are micrometers. For afocal mode, the units are afocal mode units. The other parameters are:

Samp: The pupil sampling, where 1 yields 32 x 32, 2 yields 64 x 64 etc.

Wave: The wavelength number to use (use 0 for polychromatic).

Field: The field number.

Type: 1 for encircled, 2 for x only, 3 for y only, and 4 for ensquared.

Refp: The reference point to use. Use 0 for chief ray, 1 for centroid, 2 for vertex, and 3 for middle of the spot.

No Diff Lim: If 0, the results are scaled by the diffraction limit, otherwise, no accounting of diffraction is done.

See also GENF, DENC, DENF, and XENC.

Geometric Encircled Energy (fraction). This operand computes the fraction of geometric encircled, ensquared, x only, or y only (enslitted) energy at a given distance from the reference point defined by Dist.

The options and settings are identical to GENC, except Dist, which here is used as the distance at which the fraction of energy is desired. See also GENC, DENC, DENF, and XENC.

Extended source encircled energy (distance). This operand computes the distance in micrometers to the specified fraction of extended source geometric encircled energy, using whatever the current default settings are. To use this operand, first define the settings on the extended source encircled energy feature as desired, then press Save on the settings box. The only settings that are overwritten are those set by Type, Wave and Max Radius.

Type is 1 for encircled, 2 for x only, 3 for y only, 4 for ensquared, 5 for x distribution, and 6 for y distribution. When using Type 2 or 3, the distance calculated is the"full" slit width containing the fraction of energy defined by Frac. This is the "full" slit width of the [-x, x] or [-y, y] range respectively, centered on the chosen reference point. For example, if Dist = 20 µm, this means that the fraction of energy is contained in a slit width of +/- 10 µm.

Wave is the input wavenumber. 

Frac is the fraction of energy desired, and must be between zero and 1, exclusive. Frac is ignored for type 5 or 6; for these types the returned valued is the full width half max independent of Frac.

Max Radius is the maximum distance in radial distance in micrometers. If this value is zero, the default setting is used.

See also XENF, DENC, DENF, GENC, and GENF.

Extended source encircled energy (fraction). This operand computes the fraction of extended source geometric encircled, ensquared, x only, or y only (enslitted) energy at a given distance from the reference point.

The Type is 1 for encircled, 2 for x only, 3 for y only, and 4 for ensquared. When using Type 2 or 3, the fraction of energy in the PSF is calculated in the [-x, x] or [-y, y] range respectively, centered on the chosen reference point. This is the full slit width given by Dist. For example, if Dist = 20 µm, the fraction of energy is calculated for a slit width of +/- 10µm.

Wave is the input wavenumber. 

The options and settings are identical to XENC, except Dist, which here is used as the distance at which the fraction of energy is desired.

See also XENC, GENC, GENF, DENC, and DENF.