Case Study – using

QED Analysis Notebooks

to evaluate an optic

against specifications


1. Introduction

Every optics manufacturer needs to analyze surface form against the tolerances on a drawing.  Screenshots from the metrology analysis software are often employed, but they are not ideal for this purpose.  QED's Analysis Notebooks automatically evaluate measurements against common optical specifications.  A notebook summary page presents the pass/fail results in an attractive format.


Goal: Analyze a surface against optical specifications

  • Compute key quality metrics from a measurement result
  • Demonstrate conformance to specification in an attractive, easy to read report


Sounds easy enough. What are the challenges?

  • While drawings are standardized, data presentation is not
    • The “de-facto” standard is one or more screenshots from metrology software
  • It is often not immediately obvious which numbers are the specifications, and how much they pass/fail by
  • Screenshots are often not ideal for presentation
    • But integrating into a report (e.g. via presentation software) is often labor intensive
  • Multiple specifications can have different processing needs
    • The analysis software may need different configuration settings for each spec



2. Example Work Flow

  • Receive optical drawing / print and commit to fabrication
  • Identify optical specifications to be evaluated
  • Fabricate the optic!
  • Obtain measurements of the optic suitable for evaluating against the optical specifications
  • Compute specification metrics on the measurements
  • Generate a quality report assessing conformance to specifications

  • We demonstrate the last 2 steps in this case study
  • We’ll take a sample optical drawing and form measurement, then evaluate against specifications and generate a QA report



3. Case Study Example: Optical Drawing

  • We'll consider the surface form of the left (aspheric) surface

QED Analysis Notebook 1






4. "Typical" Analysis

QED Analysis Notebook 2




5. "Typical" Analysis, Part 2

  • Change filter settings and display the slope

QED Analysis Notebook 3






6. How can the Analysis be Improved?

A. Specification indications

  • Clear indication of how much the specification passes/fails by
  • Prominent display of the specifications and results

B. Logically organize multiple pages

  • We would like a summary of all the specifications “up front”
  • More detailed analyses/pictures should show up later
  • Manually arranging this information is labor intensive

C. Better control of display and configuration of the analyses

  • Show key metadata (e.g. surface prescription), to give readers of the data confidence that they are looking at data from the correct part
  • Measurement controls not relevant to specifications should be hidden
  • Ability to save the complete analysis configuration for ALL specs in a single file

D. More flexibility in how specification metrics are computed

  • Custom settings for each analysis (e.g. pre-filtering for slope)
  • Slope, for example, can be computed in different ways – finer control over the computations (and any pre-filtering) is desirable





7. QED Analysis Notebook (Summary)

QED Analysis Notebook 4



NOTE: the complete 4 page notebook is included in Appendix A, available in the PDF download of this case study.




8. QED Analysis Notebook (improvements A, B)

QED Analysis Notebook 5



Download the PDF file of the case study to access the Appendix for sample detail page layout





9. QED Analysis Notebook (Improvements C, D)

QED Analysis Notebook 6






10. Conclusions

  • QED.NET Analysis Notebooks are an excellent tool for analyzing a surface against optical specifications
    • First page includes a summary of the conformance to specifications in an attractive, easy-to-read format
    • Later pages provide detailed information on each evaluated spec, and the configuration details for those specs
    • The complete analysis configuration (computations, layout, tolerance values) can be saved for easy re-use on other parts/measurements
    • The analysis is easy to print (or pdf) over desired areas, eliminating the need for tedious editing (the notebook is “presentation ready”)
  • The notebooks remain incredibly flexible and powerful
    • The specification analysis notebooks are built with QED’s “regular” analysis notebook technology, which includes the incredibly flexible scratchpad and process diagrams behind it