Professional Detailing2 min read

Laser-Diffraction Coating Reports: Keep the Optical Model with the Result

A particle-size chart is more useful when the assumptions used to calculate it are retained. For a laser-diffraction study, ask the laboratory to identify the optical model and relevant material inputs.

Updated · NANOLAB Knowledge

The key distinction

Mie-based laser-diffraction analysis uses optical information about the particles and dispersing medium. Treat those inputs as part of the measurement record, rather than assuming every instrument report used identical settings.

Practical checks

  1. Request the method settings that affect interpretation.
  2. Separate a change in analysis assumptions from a change in the physical sample.
  3. Have the laboratory assess whether results can be compared on a common basis.

Example

Illustrative example: two reports use the same sample identifier but different optical inputs. The reviewer first resolves that difference before interpreting the apparent size shift as a manufacturing change.

Scope and limits

Do not select optical constants merely to obtain a preferred distribution. Method suitability and the defensibility of inputs belong with the competent laboratory, not a marketing comparison.

Related guidance

Technical references: Malvern Panalytical: laser diffraction. These sources describe their stated methods or products; they do not certify NANOLAB products or establish compatibility with an unlisted surface.

Ask NANOLAB about the exact product and intended use. Use the current product documentation for formulation-specific instructions.