Lead bricks were placed around the radioactive source so that the escaping gamma rays would be limited to a collimated beam rather than filling the lab.
I need to collimate my telescope so that the images are clearer.
collimate the beam.
Collimate around the sides of the limb and include the whole calcaneus, the distal tibia and the proximal metatarsus.
collimate so that the patella, the distal femur and the proximal tibia are included.