Hi Mo.,

First, to change the surface Thickness, you simply need to write:

MySurfaceNumber = 1
MySurface = TheSystem.LDE.GetSurafceAt(MySurfaceNumber)

# This is where you change the thickness
MySurface.Thickness = 12.3

I understand why you tried to use the ThicknessCell, but this is only to setup a solve on the thickness. The way you accessed the Tilt About X is correct though.

Second, I’m not an expert in Python, but unless you work with list or arrays, the variables don’t work as pointers. When you type:

mir1_tiltX = surf36.GetCellAt(14).DoubleValue

Then mir1_tiltX will be a Double variable containing a Double value that corresponds to the actual Tilt About X at that point in time. Python doesn’t associate your surface with mir1_tiltX. I hope that makes sense. What you could do instead is have the Tilt About X cell as a programming variable, and update this one in the loop like so:

# This is your Tilt About X cell
mir1_tiltX = surf36.GetCellAt(14)

for indextilt, stepTilt in enumerate(np.arrange(-10, 10, 5)):
  mir1_tiltX.DoubleValue = round(stepTilt, 2)

Third, there are several Merit Function operand to retrieve the spot size: RSCE, RSCH, RSRE, and RSRH:

In the ZOS-API, you can use the GetOperandValue method from the Merit Function Editor interface to calculate the value of a single operand. Here is an example with RSCE:

# RSCE parameters
Sampling = 5 # this is in number of rings
Wave = 1
Hx = 0.0
Hy = 0.0

# RSCE operand type
RSCE = ZOSAPI.Editors.MFE.MeritOperandType.RSCE

# Print RSCE value
print(TheSystem.MFE.GetOperandValue(RSCE, Sampling, Wave, Hx, Hy, 0, 0, 0, 0))

By doing it this way, it shouldn’t open any window. Also note that all the analyses have a method CloseAnalysis that you can call to close them.

Here is how the RSCE operand compares with the Spot Diagram in the Double Gauss sample file:

In the Spot Diagram you need to increase the sampling quite a bit to get down to a similar value as calculated by RSCE, and this is because the RSCE is using the same sampling as for the Gaussian quadrature in the Merit Function optimization.

This is the result with Python:

0.3598208788233937

I hope this helps, and good luck on your tolerancing journey (let us know how it goes ,

David

Hey @David.Nguyen,

First of all sorry for my late response and thank you very much! Your reply was a great help for me and my tolerance analysis. The only thing i recognized, that was not going really well, were when i tilted my components (e.g. the first mirror) so far that the rays no longer occur on the detector. I expected to get a really low or zero value for the RMS Radius, but instead it were just decreased a little. It seemed to me as it just decreases it by a certain value. Anyway it does not correlate with the RMS Radius shown in the Spot Diagram. Do you, by any chance know why that is?

And also i would love to get the result of my Physical Optics Propagation without opening and closing windows. Is there a way to achieve that, too?

Best regards,

Mo