A comprehensive range of tonometer solutions for slit lamps

Haag-Streit Tonometers

Fast and reproducible IOP measurement

Goldmann applanation tonometry has been the gold standard in tonometry for many decades. It is based on the Goldmann principle—tried and tested during more than 50 years of usage with millions of patients.

AT 900 Type BQ / BP 900

For BQ 900 and BP 900 slit lamps

The device is mounted permanently on the microscope arm. It provides a parking position and can be easily placed into working position. The measurement is obtained through the right eyepiece.

AT 900 Type R

Fits Haag-Streit BI 900 & BM 900 slit lamps, and third party models

Our device fits the Haag-Streit BI 900 and BM 900 slit lamps, as well as many third party models. Mounted on top of the microscope, it can be left on the slit lamp permanently as it provides a parking position and can be easily swiveled into working position. The measurement is obtained through the right eyepiece.

AT 900 Type T

For Haag-Streit BQ 900, BP 900, BM 900 & BI 900 slit lamps

Mounted on a guiding platform placed over the slit lamp axis: the tonometer is placed on the slit lamp only when applanation tonometry is performed. The instrument can be moved between two positions for observation through the right or left eyepiece.

AT 870

For “Z-Style” slit lamps

The AT 870 is mounted permanently on top of the slit lamp microscope. The feeler arm protrudes from above into the beam path of the microscope and illumination unit.  If the feeler arm is swivelled into the park position, the slit lamp can be used immediately for the examination. The applanated surface is observed monocularly through the left eyepiece of the stereo microscope.

Goldmann Tonometer Prisms

Excellent optical quality

Our sustainable Goldmann measuring prisms are reusable and are characterized by their excellent optical and mechanical performance, enabling fast and reliable IOP measurement in daily practice. The prisms are produced in Switzerland with manufacturing standards of the highest level.

Tonosafe Tonometer Prisms

Convenient, safe & accurate

Tonosafe is our single-use tonometer prism and avoids the need for time-consuming and laborious cleaning. It effectively reduces the risk of cross infection, even in the most demanding scenarios. Calibrated to Goldmann standards, Tonosafe delivers accurate results with all Goldmann tonometers. 


Haag-Streit UK Service Division

Let us service your tonometer

HS-UK is the only UK service provider that uses genuine Haag-Streit tonometer parts and test jigs calibrated to Haag-Streit standards, as it is the only Haag-Streit authorised applanation tonometer service agent in the country. You can rest assured we use state-of-the-art testing and calibration equipment and genuine parts and materials, all manufacturer-supplied. At our purpose-built, fully-equipped workshop facility, your tonometer will be fully-inspected, its worn or broken parts replaced, including cone arms and bearings, and its calibration will be checked, all before it is thoroughly decontaminated and returned to your clinic. 

AT 900 model BQ / BP AT 900 model R AT 900 model T
Measuring principle
Goldmann principle
Measuring force generated
Through leverage weight
Via spring weight
Measurement range
Measurement range 0 – 80 mmHg 0 – 80 mmHg 0 – 80 mmHg
Meridian setting
Meridian setting
Measurement deviation
The measurement deviation in the measuring prism is in the measuring range from 0 – 58.84 mN and amounts to a maximum of ±1.5% and to a minimum of ±0.49 mN of the nominal value.
Working settings
Weight (kg) 0.78 kg / 1.72 lbs 0.73 kg / 1.6 lbs 0.49 kg / 1.08 lbs
Width ≤0.49 mN ≤0.49 mN ≤0.49 mN
Working temperature 10° to 35° C / 50°F to 95°F 10° to 35° C / 50°F to 95°F 10° to 35° C / 50°F to 95°F
Tonometer fixation
BQ 900
BP 900
BI 900
BM 900
BX 900
Third party slit lamps contact your local distributor contact your local distributor contact your local distributor
Tonometer prisms
Goldmann tonometer prisms
● standard | ○ optional | − not available | □ not recommended

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