L-Prism: An optical element featuring an angular prism at its core, paired with an L-shaped adjustable locking bracket to serve as a collaborative optical target for surveying.
The core element is made of K9 optical glass and utilizes three-sided orthogonal total internal reflection to reflect the laser beam back along its original path. 
When used in conjunction with total stations and automated monitoring systems, it is employed for the precise monitoring of structural displacement, settlement, and deformation in engineering projects.