Solid Test Plate

Calibration and Services

Refractometer Calibration

Solid Test Plates

Solid Test Plates are precision ground optical components that can be placed on the prism of a refractometer to provide a reading of traceable value. Solid Test Plates are often used with optical instruments such as Abbe refractometers or optical hand held instruments as they are not effected by chemical or temperature change. In particular, hand held refractometers may be verified using a solid plate where the range of the instrument prevents the use of water for zero calibration (for example refractometers with a range of 10-30% water in honey).

Solid Test Plates are not generally suitable for use with digital refractometers as the prism surface is too small for good contact to be made and it is possible to generate small errors when using them on such instruments.

Order Code Instrument Refractive Index Brix
10-44 Abbe (glass) 1.52206 RI 91.6
10-46 Abbe (silica) 1.45839 RI 67.1
72-200 Hand held (silica) * 1.45839 RI 67.1
72-207 Hand held (glass) * 1.48757 RI 78.8 (honey)

Contact liquids are required for applying test plates or solid samples to refractometer prisms as below:

Order Code Description
10-43 Monobromonapthalene (6ml) for solid samples up to 1.65 RI
10-61 Methylene Iodide (3ml) for solid samples up to 1.74 RI
Items coded 10-44 and 10-46 are complete kits including contact liquid and certificate.
Items marked * require contact liquid and certification to be ordered separately.

Certification Service

All Solid Test Plates are supplied with a certificate of verification at point of order, carried out at 589.3nm and at 20°C to the accuracy as described in the table below: 

Please note that only silica plates may be returned for reverification. Therefore customers wishing regular certification are advised to purchase a silica test plate.

Test Plate Certification at point of Sale (RI) Retrospective Certification (RI)
Silica ±0.00006 ±0.00006
Glass ±0.0002 Not available