FilmStar News 2010 Digest

Technical Issues - FilmStar News 2010

Other editions: 2006, 2007, 2008, 2009

1. DESIGN 2.61.0100 adds the ability to edit and view (%R and %T) optimization targets in the Interactor. In addition, an imported spectrum (blue line) is retained in memory when closing and reopening the Interactor. Click Spectra...Clear Data to delete the line. (To test this function, click Spectra Copy followed by Paste. Modify the design to expose the blue line hidden under the red line.)

2. Advanced users: A Workbook menu command and toolbar icon have been added to the Interactor. To prevent unwanted results, only a few Workbook BASIC functions are available in Interactor mode: WbCopy, WbGetNum, WbGetText, WbRecalc. In the Interactor Options box, enable Workbook.. Auto-Update to automatically evaluate in the Workbook. Calculations occur before any BASIC macro runs, making it possible to utilize Workbook values in macros.

3. FTG-style file dialogs, an optional holdover from Windows 3.1 when only 8-character file names were allowed, have been eliminated in favor of standard Windows common dialogs. If you miss the 50-character descriptions that were part of FTG-style dialogs, check the following box

in File.. Configuration.. Preferences. Users can also utilize NTFS File Properties.

January 18

Dr. Mikhail Polyanskiy laudably maintains RefractiveIndex.INFO, a web compendium of n,k data for a number of materials. Data is presented in two formats: tables and dispersive formulas. Users should verify data and realize that film properties are different from bulk properties.

1. Tabulated tables have the following format (CSV). Note that lambda is in microns

lambda,n,k
6.199E-4,0.999512,7.50E-5
6.351E-4,0.999486,8.16E-5
6.508E-4,0.999459,8.87E-5
6.665E-4,0.999432,9.63E-5
...

CSV files can be automatically imported with FilmStar INDEX macro RefractiveIndexInfo.bas, included in the FilmStar installer or in basic32.zip. The program removes duplicate wavelength entries, so that the number of wavelengths may be slightly less than given by Polyanskiy. Data is also available in tab separated TXT files, handy for copying and pasting into Excel or into FilmStar INDEX. If pasting data, however, be sure to open INDEX's Index Table dialog to check for and remove duplicate wavelength entries. Some of the index tables have very wide wavelength range. We have consequently modified INDEX's auto-scale function to use log wavelength axis when the max/min wavelength ratio is >=20.

2. A variety of Sellmeier-type relations are utilized for glasses and similar materials. These can be imported into DESIGN and INDEX by clicking 'Expressions for n' and copying the Visual Basic code to the clipboard and pasting into the User Index Function Formula dialog as shown below. Be sure to leave out 'n ='.

Dy2O3 website original:SQR( 1 + x^2/(0.3653*x^2-73e-4) )

Dy2O3 DESIGN/INDEX: SQR( 1 + x^2/(0.3653*x^2-.0073) )

Since DESIGN 2.61.0103 and INDEX 2.51.0102, most formulas can be used directly because x now substitutes for WM (wavelength in microns). A few formulas utilize scientific number notation which causes difficulties for FilmStar's equation parser. For this reason we replaced 73e-4 with .0073 (73*10^-4 works equally well.)

January 21

Another source for refractive index data is Guillaume Boisset's Luxpop.com. Click here for a direct link to the list of n,k files. While these have the same extension (NK) as Sopra files, formats are different. Users should verify data and realize that film properties are different from bulk properties.

Luxpop NK files can be imported with FilmStar INDEX macro LuxpopNK.bas, included in the FilmStar installer or in basic32.zip. Some of the tables have very wide wavelength range. INDEX's auto-scale function uses log wavelength axis when the max/min wavelength ratio is >=20.

INDEX 2.51.0120 adds Sub Display so that users may review the file header before proceeding. Users of older versions should comment out the following lines:

Display s$, "File Viewer - click <Close> to proceed", _ 
    9000, 4500, "Verdana", 10, 0
If MsgBox("Continue to import file?", vbQuestion + _ 
    vbYesNo, "Luxpop n,k") = vbNo Then End

Wavelengths are in Angstroms as indicated by the string '(A)'. If '(A)' is not found, a 'Wavelength multiplier' prompt is provided for nm and µm. (If you discover files in other units, please let us know.) NK files will open in Excel; use 'Text to Column' to convert column A into three columns A-C.

As displayed below, files may include hard X-ray to FIR wavelength ranges. The graph below includes 1175 data points.

In the graph below, wavelength range was reduced to VIS-NIR (52 points) by deleting lines in the Index Table. Hold down the <Ctrl+D> key to rapidly delete lines.

February 2

Attending OIC 2010 in Tucson in June? Looked at the Design Problems? Problem A (solar coating) is easily set up with the FilmStar Workbook. We have assembled files (OIC_2010A.zip) to help FilmStar users deal with OIC 2010 Design Problem A.

IMPORTANT: Before proceeding, open DESIGN and check
that Film Indices >= 14 in File.. Configuration.. Capacity.

The zip file includes:

1) ..\FredG_A.txt ...Sample file for loading into the Validation Tool (created by MyDesign_A.bas)

2) ..\Basic32\MyDesign_A.bas ...FilmStar DESIGN macro for creating a Validation Tool text file.

**** Be sure to change MyID$, MyName$, and MyEmail$ ****

3) ..\Index\*.itw ...OSA-supplied indices saved in FilmStar format. Files end with _OIC in order to prevent overwriting your current files.

4) ..\Data\OIC_2010.inw ...Film Indices dialog (probably you don't need this since opening the FILM Archive also opens Film Indices)

5) ..\Designs\MyDesign_A.faw ...sample FILM Archive design not quite good enough to be accepted (as shown below). Acceptance criteria: Absorptance >= 94%, Emittance <= 10%.

6) ..\Workbook\OIC 2010 - Problem A.xls ...FilmStar Workbook for evaluating and optimizing your design. To maximize Merit = Absorptance - Emittance we set Objective = (1-Merit).

Hint: In the Interactor, set Workbook Auto-Update to True to manually adjust design layers and see the effect on Absorptance and Emittance.

February 17

In working on OIC 2010 Design Problem A, we found it useful to disable Workbook constraints without permanently deleting them. This has been implemented (DESIGN 2.61.0109) by setting DataType bit 5 (adding 32 = 2^5 to DataType). Referring to the above screen shot, changing DataType = 9 to DataType = 41 disables the constraint in cell G11.

March 2

DESIGN improvements make it more convenient to utilize many materials. The Film Indices Edit menu adds Sort by Description...enabled only when all film materials have descriptions. Click View..Hide Columns <F3> to hide columns C-G and View..Restore Columns <F4> to restore them.

In the Layers Design Editor clicking View..Index Columns enables Dispersion and Description columns (click here for more information). When all film materials have descriptions, Description column cells changes from static text to pull-down. Here Layer 6 was changed from 26.26J (ZrO2) to 26.26X (HfO2) without typing 'X' in the Design column.

March 22

Does a 2 nm shift affect perceived color? What about 10 nm, as shown here? Can you replace filter glass with a dichroic coating? Referring to the highpass design below, will changing (.25L .25H)8 to (.25L .25H)3 affect color perception?

The DESIGN Interactor RGB Comparator (2.61.0200) helps users compare the color of an imported spectrum with the calculated spectrum (circle).

Set the Interactor Mode to Compare or Difference and paste a spectrum or open a measured curve. The curve must include 380-780 x1 or x5 nm. Click Evaluate.. RGB Comparator. Although the same colors are shown in the status bar, the Comparator makes differences easier to see. The screen shots below indicate the procedure step-by-step. Note that RGB simulation assumes D65 illuminant.

In Design Mode we see both reflected and transmitted colors.

Compare or Difference Mode gives reflected or transmitted color.

Click Spectra...Copy followed by Spectra...Paste to simulate
an imported spectrum, here overlapping the current spectrum.
There are now two identical color bars.

Changing Design Wavelength from 460 to 470 nm reveals two curves.
The color bar for the imported spectrum (blue line) is at the left.

Click Evaluate...RGB Interactor to display colors in an exploded format.

This capability was inspired by stumbling upon Edmund Optics 45° Reflective Dichroic Color Filters and finding that Coating Tolerances are ±15 nm. (Possibly a mistake; ±5 nm seems more reasonable.)

March 29

Responding to the above, a user pointed out the difficulty in comparing RGB colors for AR coatings. This is an issue in products such as ophthalmic lenses and camera filters where cosmetic appearance is important. While the eye distinguishes dim reflected colors, the RGB representation does not, as shown below:

Impossible to distinguish nearly black RGB colors

Click Evaluate...RGB Boost (DESIGN 2.61.0201). Specifying Boost > 1 enhances reflected colors by scaling CIE tristimulus values. Boost is disabled by setting the value to 1. Note the yellow warning message. Boost applies only to reflection. This is a heuristic method and not an accurate representation.

RGB Boost provides an indication of reflected color

April 5

DESIGN 2.61.0300 and MEASURE (Scantraq) 2.61.0200 add Report Generator action command BASRUN. This makes it possible to run a BASIC macro while printing a report. Consider the following sample macro:

Sub Main   ' Program PrtStrings.bas
    BasText$(0) = "FilmStar Automation"
    BasText$(1) = "Automation with FilmStar BASIC is the key to" & _
                vbCrLf & "increased productivity and profitability."
End Sub

The macro is then referenced in the Report Generator template with BASTEXT and BASBLOCK as follows:

<<Name Arial>><<Size 18>><<Align 1>><<Bold 1>>
FTG Software Associates
<<Name Courier New>><<Size 10>><<Bold 0>>
<<Review>><<BasRun c:\Winfilm\Basic32\PrtStrings.bas>>
<<Bold 1>><<Italic 1>>
<<BasText 0>>

<<BasBlock 1>>

The BASRUN command is placed before BASTEXT and BASBLOCK. The following appears at the bottom of the report:

FilmStar Automation

Automation with FilmStar BASIC is the key to
increased productivity and profitability.

DESIGN and MEASURE FilmStar BASIC include ReportPrint and ReportShow commands. Attempting to run a macro, from the BASIC editor or from a macro key, which subsequently triggers a Report Generator macro leads to an error message. Macros must have .bas or .bse (encrypted) extensions.

Similar capabilities are provided in MONITOR 2.52.0200. Run-sheet commands BASTEXT/BASBLOCK, and BASIC Property BasText$ are new in MONITOR. Although identical results can be obtained by separately running a macro assigning BasText$ values, including the macro in the run-sheet template eliminates an easily forgotten step. Finally, MONITOR 2.52.0200 adds BASIC Sub WsCopyAll, a subroutine which should prove especially useful for integrating Excel calculations into run-sheets.

April 26

1. In a previous FilmStar News we illustrated how popup menus can replace list boxes in assigning multiple macros to a single key.

Mselect.bas (original)

MselectPop.bas (new)

In response to a user who recently requested additional macro keys, it seemed useful to provide a new example (MselectPop.bas) in ..Winfilm\Basic32. BASIC updates are included in the most recent installer as well as in basic32.zip. While these examples utilize DESIGN, the same techniques work in INDEX, CRYSTAL, MONITOR, and MEASURE.

2. Isuzu Glass has a line of optical filter glasses which are popular in Japan. Mr. M. Kobiyama has kindly measured the filters and provided FTG Software with INDEX n,k data. Tables have been added to the FilmStar installer. When updating FilmStar, select 'Complete FilmStar installation' and check DESIGN/INDEX in the 'Select FilmStar Components' dialog. You will then have the option to install Isuzu filter glass.

June 22

A FilmStar user at OIC 2010 raised the following issue: How can a FILM Archive be protected against another user changing referenced n,k files (*.itw)?

One solution is to enable Archive n,k Data (File menu). This attaches n,k data directly to the design. Another possible solution is to assign read-only status to the FILM Archive and referenced n,k files by right-clicking on the file name in Windows Explorer and checking the read-only attribute.
FilmStar can also set read-only status in BASIC macros. FS_Secure.bas copies a FILM Archive and referenced n,k files to a new subdirectory under ..Winfilm\Secure.
Macro FA_Secure_Open.bas then opens the FILM Archive from ..Winfilm\Secure. Use DefPath.bas to reassign default directories.
Supporting these methods, INDEX 2.51.0200 adds a Read-only indicator in the toolbar reminding users about the file status. Attempting to re-save the file with the same name leads to an error message.

August 30

DESIGN 2.61.0317 adds Edit...Reverse Segment to the Groups Mode design editor. This helps users combine designs onto one or more substrates. While designs can also be reversed in the Design Macro editor, it may be more intuitive to do so in the Groups Mode editor.

This section reviews a technique for combining multiple designs. Both entrance medium (AIR) and exit medium (SUB) have index 1.0. Previously designed Lowpass and Highpass filters are opened in the Groups Mode macro editor as shown here. When treated as a normal one-side design, the H layer will be next to the glass substrate.

Effectively the design is deposited onto AIR and the substrate is treated as a massive layer.

The sequence for combining designs is shown below.

1. Starting design is 2G (2 mm glass).
2. Insert Lowpass design before 2G with Macro...Insert 1 (<Shift+F1>).
3. Insert Highpass design after 2G with Macro...Insert 2 (<Shift+F2>).
4. Lowpass is backwards! Highlight the stack and click Edit...Reverse Segment (<Ctrl+S>).
5. Final design now has the Lowpass outer H layer adjacent to glass.

Download WideBandpass.faw and copy to ..\Winfilm\Designs to try the above example.
The Lowpass Only curve was plotted after ignoring the highpass stack (layers 26-47) in the Layers Mode design editor.

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