platen

A platen is a flat, rigid plate used as a supporting or impression surface within various machines and devices. It is typically made of metal, glass, or hard composite and can be stationary or movable, sometimes heated or equipped with specialty surfaces to suit a given task.

In printing and image transfer, the platen provides the contact surface against which inked type, raised plates, or other image carriers press the substrate. In letterpress, offset, and related processes, the platen helps regulate contact pressure and alignment to produce a clean impression on paper or film. In die-cutting, embossing, and hot-stamping machines, platens carry dies or stamps and transmit force to transfer complex patterns onto substrates.

In modern fabrication and hobbyist contexts, the term often refers to the build plate or work surface of a 3D printer, CNC mill, or laser cutter. A build plate serves as the foundation for the object being formed and may be heated to improve adhesion and reduce warping. Surfaces may be textured or coated to improve grip, and some platens use vacuum or magnets to secure workpieces.

Other specialized uses include photographic equipment and imaging systems, where a plate or platen acts as a stable support for photographs or samples, and medical or laboratory instruments, where patient or sample platens provide a flat, controllable surface for positioning during procedures or analyses. In many mechanical contexts, platens are an integral part of hydraulic or mechanical presses, providing a flat, sturdy platform for applying force.

Overall, platens are essential as flat, stable contact surfaces that enable precise transfer, shaping, or support across a wide range of industries and applications.