Description

This subroutine sets the configuration parameters for a grating of the type "Two source user-recorded holographic optical element".  The grating OPL polynomials for Source 1 or Source 2 (or both) should be re-recorded using the DiffractHOEExRecord() function after changes are made to the grating.

Syntax

SetDiffractHOEEx( grat, src1, src2, is1real, is2real, ncoefs1, ncoefs2 )

Parameters

grat As Long

Node number of the grating surface whose "Two source user-recorded holographic optical element" specification is being modified.

src1 As Long

Node number of the source being used as recording source 1 in the grating specification.  Use -1 for the "None" option, in which case active rays in the buffer will be traced during the recording step.

src2 As Long

Node number of the source being used as recording source 2 in the grating specification.  Use -1 for the "None" option, in which case active rays in the buffer will be traced during the recording step.

is1real As Boolean

Set to True if the source 1 OPL is "real" and set to False for the "virtual" option.

is2real As Boolean

Set to True if the source 2 OPL is "real" and set to False for the "virtual" option.

ncoefs1 As Long

Specifies the number of polynomial coefficients to be used for OPL fitting during the recording of grating source 1.

ncoefs2 As Long

Specifies the number of polynomial coefficients to be used for OPL fitting during the recording of grating source 2.

Example

The example below demonstrates how to retrieve and report the current configuration for a grating of the type, "Two source user-recorded holographic optical element", modify the grating configuration, and re-record the hologram.

Sub Main

    'User-recorded grating surface

    Dim grat As Long

    grat = FindFullName( "Geometry.HoeX Grating.HoeX Grating.HoeX Surf" )

    'Retrieve current grating specification

    Dim src1 As Long, src2 As Long

    Dim is1real As Boolean, is2real As Boolean

    Dim ncoefs1 As Long, ncoefs2 As Long

    GetDiffractHOEEx( grat, src1, src2, is1real, is2real, ncoefs1, ncoefs2 )

    'Print summary of grating specification

    Print ""

    Print "Grating surface: " & GetFullName( grat )

    Print Chr(9) & "Source 1" & Chr(9) & "Source 2"

    Print "Node:" & Chr(9) & GetName(src1) & Chr(9) & GetName(src2)

    Print "Real:" & Chr(9) & is1real & Chr(9) & is2real

    Print "Terms:" & Chr(9) & ncoefs1 & Chr(9) & ncoefs2

    'Modify the grating specification by doubling coefficients and re-record both sources

    Dim nRays As Long

    SetDiffractHOEEx( grat, -1, src2, is1real, is2real, 2*ncoefs1, 2*ncoefs2 )

    nRays = DiffractHOEExRecord( grat, True, True )

    'Report recording

    If nRays = 0 Then

        Print "Recording failed."

    Else

        Print "Rays used in hologram recording: " & nRays

    End If

End Sub

See Also

Diffraction Grating Script Commands

Diffraction Gratings