Reflectance standards

Spectralex reflection standards (diffuse reflection standards) are made from our high-purity optical PTFE . This pure material provides the highest known diffuse reflection in the spectral range of 250–2500nm. The reflection behaviour is therefore almost perfectly Lambertian. In the spectral range of 300–1500 nm, the pure material achieves a reflection value of up to 99%.

The addition of special black pigments leads to the generation of additional defined reflection grades (greyscale) in the reflection standards that are needed in order to identify and determine the linearity of optical detector systems. In addition to our white standards (Lambertian emitters), our product range also includes a number of different grey standards (grey emitters, black emitters) for use in your optical applications.

Spectralex is also UV-resistant, water-repellent (hydrophobic) and resistant to almost all chemical compounds (the physical properties may change if additional substances are added). The material and the reflection standards it is used to produce are therefore very durable and resistant to environmental influences.

The optically constant reflection spectrum, the Lambertian BRDF properties and simple maintenance steps in the event of contamination make Spectralex the perfect reference test piece in the calibration of optical systems.

Lake Photonics has a calibration laboratory for measuring the diffuse reflection of flat surfaces (spectral radiance factor ß(8°/d)).

The measurements are taken using a UV-Vis-NIR spectrophotometer (Lambda 950S) by PerkinElmer®. The spectral range of the measurements is between 250 and 2450nm. The measurement data is traceable to the National Metrology Institute of Germany (PTB), and is provided electronically in measuring steps of 1nm. A certificate with printed measured values in 50nm steps is also provided.

Lake Photonics GmbH was founded in the economically strong Lake Constance area of Germany, and is your ideal competent and reliable partner in the field of diffuse reflection and transmission materials.

Our optical materials and the semi-finished products these are used to produce are obtained from selected suppliers. We can of course also offer customer-specific one-off productions in addition to our basic range.