Timble Type 360 Degree Surveying Prism for Robotic Total Station

Model: TB360

Specifications:

Prism Constant: 2mm

Prism Angle Accuracy: ≤5"

Prism Size: 25.4mm

Target Range:400m

Features:

Trimble Type 360 degree prism assembly features seven 25.4mm silver-coated prisms and incorporates a protective rubber bumper on the exterior ring.

The built in bulls-eye bubble helps keep the prism level when used with a stakeout point.

The prism has a 5/8*11 mounting thread.

This 360 prism is compatible with all robotic total station like Trimble, Topcon, Sokkia, Leica etc.

Optical Survey Prism Applications:

Survey prisms are used by surveyors and engineers to measure the change in position of a target that is assumed to be moving. Survey prisms are used for a wide range of monitoring applications including:

• Rail Monitoring
• Settlement Monitoring
• Displacement Monitoring
• Deformation Monitoring
• Convergence Monitoring

Prism Range
Surveying Prisms, also known as retro-reflectors, redirect a measuring beam back to the EDM (Electronic Distance Measurement) for processing distance. There are two main factors for good range measurement: prism diameter and beam deviation. If the beam deviation is not accurate then the returned beam will miss the EDM completely. This occurs mainly near the maximum range of the EDM.

Prism Holder Accuracy
Prism accuracy is determined by the physical location of the prism in its canister and then to the prism holder.

Survey Prism Offsets
Some Surveying Prisms have an offset due to the fact that the transmitted beam from the EDM takes longer to enter and exit the prism. The longer time translates to a longer distance measured. The distance is corrected by using an 'offset' and/or positioning the prism in relationship to the plumb line of the prism holder. Common offsets are 0, -17.5 mm, -30 mm, -34 mm, and -40 mm. The offset is determined by multiplying the height of the prism against the refractive index of the glass used.