Figure Error (Form Error)

The imaged area of an object under inspection. This is the portion of the object that fills the camera's sensor.This specification consists of low frequency or larger errors usually peaking one to three times across a part. Form errors are typically specified as peak- to- valley error in waves or fringes, but can also be specified as a linear deviation in microns or as an RMS deviation. These are typically the most common surface specification for aspheric lenses.