Home » Wiki » Survey Prisms » Leica GRZ4 360° Prism

Leica GRZ4 360° Prism

Description

The Leica GRZ4 360° Prism is a reflector suitable for all robotic TPS work performed with a survey pole.

Whilst the Leica GRZ4 has a typical 3D pointing accuracy of 5.0mm, a better one can be achieved by aiming on the yellow marker arrow. When manual pointing is used, the accuracy increases to 2.0mm.

The Leica GRZ4 has six joined corner cube prisms, allowing the measuring beam to reflect back to the source from all positions.

Specifications

Model:GRZ4
Manufacturer:Leica
MPN:639985
Height Offset:86.0 mm
Absolute constant: -11.30 mm
Leica constant: +23.10 mm
Dimensions (W x H x D):93x93x145 mm
Centring accuracy:±5.0 mm
Mount:12mm (Leica) Spigot

Notes:

In order to achieve the 2.0mm accuracy, the instrument crosshair has to be horizontally aligned with the yellow arrow marker on the target body.

Leica GRZ4 360° Prism FAQ

Below is a list of frequently asked questions about Leica GRZ4 360° Prism.

What is the prism constant for the Leica GRZ4 360° Prism?

The absolute prism constant (true value) for the Leica GRZ4 360° Prism is -11.3mm. The prism constant as defined for Leica instruments for Leica GRZ4 360° Prism is 23.1mm. For a more detailed explanation on prism constants please see this article.

Can I use the Leica GRZ4 360° Prism with a Leica instrument?

Yes, you can use the prism with a Leica instrument as long as you set up the correct prism constant in the instrument settings.

What is the prism constant value that I need to use with a Leica instrument?

In order to use the Leica GRZ4 360° Prism with a Leica instrument you should use 23.1mm as the prism constant value.

What is the height offset of the Leica GRZ4 360° Prism?

The Leica GRZ4 360° Prism height offset is 86.0mm. This is measured from the mounting point to the centre of the prism.