Trapezoidal imaging is on Linear Probes (L7, L15 and L20). The Trapezoidal imaging extends the field of view by creating an image base wider than the footprint of the transducer, which allows to include more posterior and lateral tissue.
How it works
Enable Advanced Imaging controls in the Settings Page
In the Scan page, tap the Imaging Mode & Tools Menu
Tap the the Trapezoidal imaging icon to enable
Note: The imaging field of view will be changed while in Trapezoidal imaging.