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Tolerance analysis knowhow bases on Energy

  • 9 September 2021
  • 3 replies
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Dear All.

I wonder if it is possible to analyze the amount of incident energy according to tolerance through Criterion's 'Merit Function' or 'User Script' in the SC rather than the NSC during tolerance analysis. (I want using Monte Carlo Simulation)

Energy is important because the amount of incident light determines the performance of the optical system.

Energy change due to AR coating repeatability is considered separately.

Thank you in advance.

 

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Best answer by Sandrine Auriol 16 September 2021, 14:35

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Userlevel 6
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Hi!

You can use the encircled energy criterion to get the amount of energy on your detector. Be careful that the result will be in afocal units if your system is afocal and Afocal Image Space is ticked in the System Explorer.

For example I have opened the sample file called "Zemax\Samples\Sequential\Afocal\Beam Expander.ZMX".

We can see that 86% of the encircled energy is contained in an angle of 3.7 arcsec around the average.

You can untick afocal image space to get a result in distance.

You can also use the Geometric Image Analysis to do that and use the IMAE operand. 

All these operands can be retrieved with a script and during the sensitivity and Monte Carlo run.

 

I am not sure I understand this last sentence “Or is it only possible to sensitivity analysis according to the tolerance change of a single component after non-sequential conversion using the 'convert to NSC Group' function?” What do you mean there? Sorry.

Sandrine

Thanks for your reply.

The optics currently being analyzed for tolerance are beams collimated at each angle (Telecentric Optics). Can I use Encircled Energy to obtain a Monte-Carlo Histogram of the amount of energy incident on the detector surface?

Or is it only possible to sensitivity analysis according to the tolerance change of a single component after non-sequential conversion using the 'convert to NSC Group' function?

The change in the total amount of energy incident on the detector according to the tolerance is an important factor in the performance of the optical system currently being analyzed.

 

regards,

Csilla

 

Detector → Photo Diode

 

Userlevel 5
Badge +2

Hello,

Thanks for your question here on the Community forums!

In sequential mode you may analyze the encircled, ensquared, or enslitted energy, either by distance or fraction, with the DENC, DENF, GENC, GENF, XENC, or XENF operands. These operands will describe diffraction, geometric, and extended source cases respectively. For further details, please check out the Help system at:
The Optimize Tab (sequential ui mode) > Automatic Optimization Group > Merit Function Editor (automatic optimization group) > Optimization Operands by Category > Encircled Energy (optimization operands by category)

In order to report these operand values in the tolerance reports, you can use a User Script and apply the REPORT command as discussed in this knowledgebase article:
How to get any optimization operand value in the tolerance report – Knowledgebase (zemax.com)
You may read more about this topic in the Help system at:
The Tolerance Tab > Tolerancing Overview > Using Tolerance Scripts

If you have further questions, please do not hesitate to ask.

Best,
Csilla

 

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