Meaning
Non-contact measurement provides data on the surface roughness and three-dimensional shape of a material. Optical profilometry directs a light source, often a laser or a white light beam, at a sample and analyzes the reflected signal to reconstruct the surface map. This method provides high resolution data without physically touching or damaging the part.
It is a standard tool in quality control for semiconductors and medical devices.
Interferometric Analysis
Depth measurement occurs by comparing the phase difference between two light beams. One beam reflects off a perfectly flat reference mirror while the other reflects off the test surface. As the instrument scans the sample, it detects tiny variations in height that correspond to nanometer scale features.
This process produces a detailed topographical image of the material.
Surface Finish
High precision components require a specific level of smoothness to function in a vacuum or a high pressure environment. Using optical profilometry, a technician can calculate parameters like average roughness or the maximum height of the profile. These figures confirm that the polishing or grinding process met the design requirements.
Any stray scratches or pits are immediately visible in the 3D model.
Inspection Throughput
Rapid scanning capabilities allow this technology to be used near the production line for frequent audits. Because there is no physical probe to wear down or break, the system maintains its accuracy over thousands of cycles. This speed enables a manufacturer to check a higher percentage of parts than traditional contact methods.
Better data density leads to more reliable conclusions about the stability of the manufacturing process. The software accompanying the hardware automatically flags parts that exceed the roughness threshold. This integration allows for immediate sorting of pass and fail items.
It also generates a digital record that can be shared with the end customer as proof of quality. In the semiconductor industry, this allows for the inspection of wafers between each layer of deposition.
