Optical measurement / Chapter / Three notes
Distance, Displacement, and Thickness
Three connected notes on selecting optical sensors, measuring thickness, and interpreting surface form and wavefront error.
Start with sensor principlesFollow the light path before interpreting the distance.
Choose a sensing principle that can resolve the relevant interfaces on your part. Then distinguish physical thickness from optical path length, and connect measured topography to surface form error, texture, and optical wavefront performance.
- 01 Application note + calculator
Selecting Optical Distance and Displacement Sensors
Match the ranging principle, surface response, and spatial coverage to the measurement task.
Read the note - 02 Application note + calculator
Measuring Thickness and Refractive Index
Separate geometric thickness from optical path, and use independent gaps to resolve an unknown material.
Read the note - 03 Application note + calculator
From Surface Topography to Wavefront Error
Separate form, waviness, and roughness, then connect surface form error to optical performance.
Read the note
Surface finish, slope, material, access, motion, and uncertainty determine which measurement chain will work.
Discuss your dimensional measurement →