
DFTFRinge 6.0 released
~79 GBytes. Despite the error messages I appear to have a version of DFTFringe64 version 6 that runs and at least some of the files that the error messages were generated for are present. Attempts to
~79 GBytes. Despite the error messages I appear to have a version of DFTFringe64 version 6 that runs and at least some of the files that the error messages were generated for are present. Attempts to

By
Bruce Griffiths
· #31926
·


DFTFRinge 6.0 released
Yes, including the previous version. Directories are on a local hard drive. Bruce
Yes, including the previous version. Directories are on a local hard drive. Bruce

By
Bruce Griffiths
· #31924
·


DFTFRinge 6.0 released
Dale Tried a different installation directory with same result. cmp, dll, odt, png, html files gave same error message Error opening file for writing. Even when running installation as Administrator.
Dale Tried a different installation directory with same result. cmp, dll, odt, png, html files gave same error message Error opening file for writing. Even when running installation as Administrator.

By
Bruce Griffiths
· #31922
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DFTFRinge 6.0 released
George AFAIK no version was running although earlier versions are installed. Bruce
George AFAIK no version was running although earlier versions are installed. Bruce

By
Bruce Griffiths
· #31918
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DFTFRinge 6.0 released
Dale It fails to write a number of files during installation attempts. Bruce
Dale It fails to write a number of files during installation attempts. Bruce

By
Bruce Griffiths
· #31916
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DFTFringe 6.0 video
Dale Zernike filtering certainly looks useful. I've come across a few papers on its efficacy. Bruce
Dale Zernike filtering certainly looks useful. I've come across a few papers on its efficacy. Bruce

By
Bruce Griffiths
· #31907
·


Annular interferogram processing by DFTFringe
George Your statement about the relationship between the amplitudes of various annular Zernike coefficients and the ptv for that term is incorrect the multipliers are not the same as for Zernike polyn
George Your statement about the relationship between the amplitudes of various annular Zernike coefficients and the ptv for that term is incorrect the multipliers are not the same as for Zernike polyn

By
Bruce Griffiths
· #31890
·


Annular interferogram processing by DFTFringe
George Mahajan's lecture on Zernike polynomials and beyond: https://wp.optics.arizona.edu/jsasian/wpcontent/uploads/sites/33/2016/03/ZPLecture12.pdf neatly summarises the advantages of using orthog
George Mahajan's lecture on Zernike polynomials and beyond: https://wp.optics.arizona.edu/jsasian/wpcontent/uploads/sites/33/2016/03/ZPLecture12.pdf neatly summarises the advantages of using orthog

By
Bruce Griffiths
· #31889
·


Annular interferogram processing by DFTFringe
George The point is that Zernike polynomials are not orthogonal over an annular pupil, whereas annular Zernike polynomials are. Thus, the amplitudes of the various Zernike terms are not independent wi
George The point is that Zernike polynomials are not orthogonal over an annular pupil, whereas annular Zernike polynomials are. Thus, the amplitudes of the various Zernike terms are not independent wi

By
Bruce Griffiths
· #31888
·


SPPDI® explanatory graphics added
Steve Since the annular portion of the reference beam required to interfere with test beam from the annular section of the test surface that is of interest originates from the same portion of the test
Steve Since the annular portion of the reference beam required to interfere with test beam from the annular section of the test surface that is of interest originates from the same portion of the test

By
Bruce Griffiths
· #31882
·


SPPDI® explanatory graphics added
Steve Downloaded and read the application note. It's probably a useful metric that should be added to DFTFringe. An SPPDI option that had a couple of shutters to block the return test and reference be
Steve Downloaded and read the application note. It's probably a useful metric that should be added to DFTFringe. An SPPDI option that had a couple of shutters to block the return test and reference be

By
Bruce Griffiths
· #31880
·


SPPDI® explanatory graphics added
Steve In principle if there were a switchable beam block in the reference arm then the reference arm and test arm polarisers could be aligned to be orthogonal by: 1) Clock the test arm polariser to bl
Steve In principle if there were a switchable beam block in the reference arm then the reference arm and test arm polarisers could be aligned to be orthogonal by: 1) Clock the test arm polariser to bl

By
Bruce Griffiths
· #31878
·


SPPDI® explanatory graphics added
Steve The pictorial representation of the SPPDI doesn't show the polarisation cleaner mentioned in the manual. Is the polarisation cleaner no longer used? Bruce
Steve The pictorial representation of the SPPDI doesn't show the polarisation cleaner mentioned in the manual. Is the polarisation cleaner no longer used? Bruce

By
Bruce Griffiths
· #31875
·


Fringe spacing in waves
Vladimir If using Zernike polynomials the slope is calculated in wavelengths/semidiameter. Since the angular diameter of the Airy disk is proportional to (wavelength/diameter) this is a useful measur
Vladimir If using Zernike polynomials the slope is calculated in wavelengths/semidiameter. Since the angular diameter of the Airy disk is proportional to (wavelength/diameter) this is a useful measur

By
Bruce Griffiths
· #31872
·


Bug fixes and new ideas DFTFringe.
N.B. (F/D) in the formula is the beam focal ratio. When testing at CoC the return beam the focal ratio is equal to (R/D). Bruce
N.B. (F/D) in the formula is the beam focal ratio. When testing at CoC the return beam the focal ratio is equal to (R/D). Bruce

By
Bruce Griffiths
· #31851
·


Bug fixes and new ideas DFTFringe.
Franz 1 wave of classical defocus is equivalent to an axial distance from focus of 8*((F/D)^2)*lambda. The classical defocus term amplitude = 2*C3  6*C8 + ......... This works if one is testing with
Franz 1 wave of classical defocus is equivalent to an axial distance from focus of 8*((F/D)^2)*lambda. The classical defocus term amplitude = 2*C3  6*C8 + ......... This works if one is testing with

By
Bruce Griffiths
· #31850
·


Bath and DFTFringe with very large mirrors.
Yes, if the analysis software can't cope with slope reversal then setting the zero slope region at the edge is the optimum solution. Slope reversal isn't an issue with PSI. Its not mentioned in the Ku
Yes, if the analysis software can't cope with slope reversal then setting the zero slope region at the edge is the optimum solution. Slope reversal isn't an issue with PSI. Its not mentioned in the Ku

By
Bruce Griffiths
· #31825
·


Bath and DFTFringe with very large mirrors.
If sufficient defocus is added to set the wavefront slope at the edge equal to that at the local maximum the slope is zero on a ring with a diameter equal to SQRT(3)/2 (~0.866) of the test surface dia
If sufficient defocus is added to set the wavefront slope at the edge equal to that at the local maximum the slope is zero on a ring with a diameter equal to SQRT(3)/2 (~0.866) of the test surface dia

By
Bruce Griffiths
· #31822
·


Bath and DFTFringe with very large mirrors.
Oops, I should have checked the wavefront slope at the boundary. For example if sufficient defocus is added to set the wavefront slope to zero at the edge of the test surface then the maximum slope is
Oops, I should have checked the wavefront slope at the boundary. For example if sufficient defocus is added to set the wavefront slope to zero at the edge of the test surface then the maximum slope is

By
Bruce Griffiths
· #31820
·


Bath and DFTFringe with very large mirrors.
George A coherence length of greater than 200 waves isn't an issue even with a multimode diode laser. With a typical mode spacing of 0.3nm a 600nm multimode laser diode should have a coherence length
George A coherence length of greater than 200 waves isn't an issue even with a multimode diode laser. With a typical mode spacing of 0.3nm a 600nm multimode laser diode should have a coherence length

By
Bruce Griffiths
· #31818
·
