- I am a beginner in OptiLayer. I design a coating using Needle Optimization AUTO, but I see that my design contains several thin layers. When I remove them simultaneously, approximation of my target is getting worse essentially. Maybe I am doing something wrong?
OptiLayer provides two options (Thin Layer Removal and Design cleaner) which allow you automatically remove thin layers. Of course, design performance is getting worse but in these options you are able to control merit function increase. In some cases, it may happen that some of these thin layers are very important for the design. You may try more advanced design strategies in order to get rid of thin layers (see our paper).
- I need to design a narrow band pass filter containing only quarter-wave layers. Is it possible with OptiLayer?
Yes, for your purpose you can try WDM design option. See more…
- I have to design a beamsplitter merged between two glasses. How can I specify this structure in OptiLayer?
You need to load you glass as a substrate and also as an incident medium.
- I have a problem to design a color coating. Target colors are specified in LAB system, light source is D65. I have my own program that computes some coating characteristics. I calculated color coordinates in my program and compared with OptiLayer results for the same test multilayer (100 nm and 200 nm, refractive indices 2.35 and 1.45, substrate refractive index is 1.52). My LAB coordinates for R(normal incidence) are a*=16.39, b*=18.06, L*=45.06, OptiLayer gives a*=21.11, b*=21.32, L*=45.73. I see the differences. I am sure that my program calculates correctly, all optical constants (refractive indices of materials and substrate) are the same as in OptiLayer. Where is the problem?
You did not load D65 light source and it was not included into OptiLayer calculations. Actually, if we do not include the light source, we obtain a*=16.39, b*=18.06, L*=45.06. If we include it, we obtain exactly the same values that you show a*=21.11, b*=21.32, L*=45.73.
- My target transmittance has a complicated shape. I cannot create the target using OptiLayer standard tools. Could you help me?
You can create an Excel file, specify your target there by a formula or manually and then import target values into OptiLayer using clipboard (Copy-Paste buttons).
- I need to cover a glass substrate with two different coatings from front and back sides. What OptiLayer option should I use?
You can specify a stack consisting of one medium (your glass) and specify designs for both sides. Then you can use any of OptiLayer design algorithms. Learn more about stacks…
- I need to calculate reflectance and transmittance of my design with 7 decimals, I perform calculation on a very dense wavelength grid (step is 0.000001 nm) and in a extremely narrow spectral range (from 532.599 nm to 532.601 nm). I specify 0.000001 step in the Design-->Evaluation report but I see R/T only with 5 decimals. Can I fix this problem somehow.
You should open Analysis-->Plot Engine option and specify your spectral range in the Y=f(X) r=tab (from 532.599 to 532.601) and step 0.000001 in the corresponding fields. The number of points will be automatically calculated. After pressing Next button you will see a plot R/T. Click right mouse button and go to Chart Editor. Go to Export option and choose Data tab there. Choose Excel format and press Save button. After a standard save dialog you will have the Excel file with the results of your calculations. Using Excel tools you can format cells and specify the required number of decimals.
- I obtained several solutions of the same design problem and want to compare them with respect to stability to errors in layer thicknesses and refractive indices. It is my understanding of Error analysis options that I can compare the design stability with respect either errors in thicknesses or errors in refractive indices. Do I understand correctly?
No, you can analyze sensitivity of your designs to errors in thicknesses and refractive indices simultaneously. In order to do this you have to specify errors in layer thicknesses in one of the tabs Thickness-->Coating, Thickness-->Materials, Thickness-->Thicknesses and errors in refractive indices in Refractive index tab. In the course of calculations OptiLayer will take errors in layer thicknesses on the tab that was opened just before the calculations or before moving to Refractive index tab. For example, if you specified Abs. RMS=1% on Thickness-->Coating tab, 2% RMS for all materials on Thickness-->Materials tab and 1.5% RMS for all layers on Thickness-->Thicknesses tab, move to Refractive index tab and specify 0.01 error for all refractive indices then in the course of calculations OptiLayer will take into account 1.5% errors in layer thicknesses and 0.01 offset for all refractive indices.