WHAT IS FIELD OF VIEW (FOV)?
The field of view (FOV) is the area of the sample that an optical system captures or measures in a single acquisition. It represents the portion of the sample projected onto the camera sensor or detector.
In optical metrology, the FOV determines how much of the surface can be measured at once. A larger FOV allows wider areas to be inspected more efficiently, while a smaller FOV is typically associated with higher magnification, smaller pixel size on the sample, and finer spatial detail.
However, the field of view should always be considered alongside lateral resolution, numerical aperture, sampling, and the measurement technique used. A larger FOV can improve throughput, but the selected FOV must still provide enough detail and data quality for the required measurement.
KEY ASPECTS OF THE FIELD OF VIEW (FOV)
The field of view depends on several factors, including objective magnification, optical configuration, camera sensor size, and detector resolution.
Objective magnification: higher magnification usually reduces the field of view, while lower magnification increases the measured area.
Camera sensor size: a larger sensor can capture a wider area of the sample for the same optical configuration.
Detector resolution and sampling: the number of pixels and their projected size on the sample affect how much detail can be represented within the FOV.
Measurement technique: different optical technologies, such as confocal microscopy, interferometry, or focus variation, may have different practical FOV limits and measurement performance.
Stitching: when the required measurement area is larger than the available FOV, multiple acquisitions can be combined to measure a wider surface area.
In metrology, selecting the appropriate field of view is essential to balance measurement area, lateral resolution, acquisition time, and measurement reliability.
