Ultra High Speed 3D Measurement with the Focus Variation Method

Introduction

In recent years optical 3D measurement techniques in the micro- and nano-range have become increasingly popular due to their non-destructing nature and their ability to obtain areal 3D measurements. However, most of these techniques, especially those that rely on vertical scanning, have not been fast enough for inline measurements, where measurement times of a few seconds are required. Here we present an optical measurement device based on the Focus Variation principle that is able to perform 3D measurements with 4 million measurement points within one second, making this device to one of the fasted optical 3D metrology devices in the world.