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Leica MPR122 360° Prism

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The Leica MPR122 Machine Automation power prism is a high accuracy (±2mm) 360° prism which has been utilised mainly in the iCON product line. The MPR122 is commonly used in conjunction with the CRP1 pole.

Useful for monitoring applications, the larger size of the MPR122 over the GRZ101 and L-bar designs means that ATR will locate at greater ranges.


Height Offset:50.0 mm
Absolute constant: -6.30 mm
Leica constant: +28.10 mm
Dimensions (W x H x D):70.5x99.5x70.5 mm
Centring accuracy:±2.0 mm
Mount:5/8" Thread


  • The prism height offset is ambiguous. Please use with caution and do manual measurements for confirmation.
  • The Leica MPR122 prism has a two mounting points, one female thread at the bottom and one male thread at the top. They are both 5/8″ sized threads.

Leica MPR122 360° Prism FAQ

Below is a list of frequently asked questions about Leica MPR122 360° Prism.

What is the prism constant for the Leica MPR122 360° Prism?

The absolute prism constant (true value) for the Leica MPR122 360° Prism is -6.3mm. The prism constant as defined for Leica instruments for Leica MPR122 360° Prism is 28.1mm. For a more detailed explanation on prism constants please see this article.

Can I use the Leica MPR122 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 MPR122 360° Prism with a Leica instrument you should use 28.1mm as the prism constant value.

What is the height offset of the Leica MPR122 360° Prism?

The Leica MPR122 360° Prism height offset is 50.0mm. This is measured from the mounting point to the centre of the prism.