The standard for the measurement of intraocular pressure between 0 to 78mmHg. As the area of applanation is only 3.042mm the scleral rigidity does not influence readings.

Goldmann Model Tonometer Haag Streit: This attaches to the footplate of the slit lamp and is removed from the slit lamp when not in use. Fits the Haag-Streit 900BM and 900BQ slit lamps.

Goldmann Tonometer: This tonometer Haag streit 900 is permanently attached to the slit lamp by means of a special mounting spigot.