Irradiance is a parameter of radiometry, which in turn deals with the measurement of optical radiation inclusive of the visible part of this radiant energy.
Irradiance describes the amount of radiant power imposing on a surface per unit area. To this end, irradiance measurements can be performed in the NIR, UV and VIS wavelength ranges.
Irradiance Measurement
Avantes works with various irradiance applications that range from free space measurements of radiant sources like street lights to pulsed solar simulator characterization. The AvaSpec range of instruments offers excellent resolution and stray-light rejection to guarantee the precision of these measurements.
Standard system configurations include one or more spectrometers, which are configured for the optimum range of 1100-2500nm for NIR irradiance, 360 -1100nm for VIS irradiance, and 200-400nm for UV irradiance. Although a single spectrometer can possibly be used for broadband configurations covering 200-1100nm wavelength range, only dedicated VIS/NIR (400-1100 nm) and UV (200-400 nm) channels can provide optimal performance.
The spectrometer or a set of spectrometers is joined through fiber-optic cable to a diffuser with a known surface area, and the whole system is calibrated against a NIST traceable source for irradiance.
Avantes Systems for Irradiance Applications
Avantes provides a wide range of integrating spheres and cosine diffusers for irradiance applications. The calibrated system is delivered as an integrated system and must remain in this configuration so as to guarantee the integrity of the calibration. Instead of the typical SMA, FC/PC connectors are recommended which allow repeatable re- insertion and disconnection of the fiber-optics, and hence the system can be disconnected for transportation.
.jpg)
Figure 1. AvaLight-HAL-CAL calibration source
For customers wishing to perform their own calibrations, Avantes’ intensity calibration sources are recommended. The AvaLight-HAL-CAL and AvaLight-DH-CAL (Figure 1) are available for VIS/NIR wavelengths (360-2500nm) and UV/VIS wavelengths (200-1100nm), respectively.
AvaSoft-IRRAD Software for Irradiance Parameter Measurements
Additionally, the Avantes AvaSoft-IRRAD software module allows irradiance parameter measurements, such as radiometric quantities - µJoule/cm2, µWatt/cm2, µWatt or µJoule, color coordinates X, Y, Z, x, y, z, u, v, photometric quantities Lux or Lumen, color temperature, color rendering index, and number of photons µMol/s•m2, µMol/m2, µMol/s and µMol. Moreover, the AvaSoft-IRRAD software facilitates the performance of irradiance intensity calibrations.
Conclusion
Avantes provides a wide range of calibration systems and software for irradiance applications. The AvaSpec line of instruments delivers superior resolution and stray-light rejection to ensure the precision of these measurements.
This information has been sourced, reviewed and adapted from materials provided by Avantes BV.
For more information on this source, please visit Avantes BV.