3D Shadow Removal™

There are inherent limitations in the perspective of the camera in any optical metrology system. It requires the collection of light information to determine sample profile. This phenomenon is a common challenge in the field of optical metrology. For example, when measuring an IC chip with a dense array of solder bumps. In one camera perspective, the height of the bumps on axis with the camera lens will occlude the light collection of bumps on the far side of (behind) the “visible” bumps relative to camera’s view (or perspective). This results in the loss of feature data from the shadowing caused by the on-axis bump locations.

Optoniks’ 3D Shadow Removal™ incorporates two cameras in the measurement system. The two perspectives produce shadows but at different locations on the sample (as can be seen in the two images). Using the geometry of the setup combined with intuitive algorithms, Optoniks ContourPro 4D profilometry system integrates the data between the two cameras and produces a 3D profile with minimal to no shadowing. This method permits measurement of samples where one-camera optical metrology systems cannot achieve the desired results.