Guide to UV Measurement
Why Radiometry
Radiometry can be effectively used to correlate exposure conditions to the physical properties of the cured product. The four key conditions of UV exposure can be quantified, and by relating these to the set of properties required, the range, or “process window” in which the process will operate satisfactorily, can be increased.
The physical properties of UV-cured materials are substantially affected by the lamp systems used to cure them. The development of the intended properties can depend on how well these lamp factors are designed and managed. The four key factors of UV lamps are: UV irradiance (or intensity), spectral distribution (wavelengths) of UV, UV energy (sometimes referred to as 'dose' ), and infra-red radiation or film temperature.
Radiometry is used to measure and optimize the exposure of a UV-curable material in the development or formulating lab in order to efficiently produce the desired “cure.” These measurements become the specifications of exposure in the design of production systems. Finally, radiometry is used to monitor the exposure in production systems.