Accessories
Compact, zero-offset prisms designed for precise, repeatable off-ground control, monitoring, and stronger survey geometry.
Explore field uses
What they are
Penny Prisms combine a precision prism, strong magnetic attachment, and a custom compact housing. They give field crews a fixed observation point without the bulk of a pole, tripod, or mini-tribrach, while allowing the instrument to locate the prism center directly.
Their low-profile form makes them easy to carry, place, and reuse. Pairing the prism with a fixed-point base adds repeatable forced centering, so the base can remain on the project while the prism moves between sites.
Use cases & benefits
Unlike reflective tape or sheet targets that must be sighted manually, a true prism gives the instrument a defined center to search for and lock onto. Penny Prisms support reliable observations from several practical approach angles, helping crews collect precise measurements with less uncertainty.
A strong magnetic back makes it easy to establish a temporary control point on a fence post, light pole, structural member, or other suitable metal surface. Elevated placement can improve line of sight while avoiding ground markings, pole-leveling error, and exposed tripod or tribrach setups.
The compact housing can remain unobtrusive in locations where a larger monitoring prism would attract attention or interfere with site activity. When the installation permits, the magnetic back can be supplemented with contact adhesive to create a durable, fixed monitoring point.
A companion fixed-point base can be secured permanently while the prism remains removable. Chamfered mating surfaces and magnetic retention guide the prism into the same centered position each time, allowing precise points to be deployed or removed in seconds across multiple projects.
Penny Prisms can serve as common points, check points, foresights, backsights, or resection points within a control network. Their fixed, zero-offset geometry adds precise and repeatable observations that can strengthen traverses and help connect scan targets to established control.
The prism, magnetic attachment, and custom housing are combined into a compact assembly designed around practical field constraints. Several units can fit in a vest pocket, giving crews flexible control options without carrying a separate pole, tripod, or full-size prism assembly for every point.
Looking ahead
A future revision may add a QR code to the reverse of each Penny Prism. The code can lead directly to this page, giving field users quick access to use cases, setup guidance, specifications, and product updates.
Field-built solutions
Accutech develops practical accessories to make precise field work faster, safer, and more repeatable.