First in Full Range PDA Spectrometer, Spectroradiometer and Spectrophotometer Systems
1 Canal Street  ◊  Unit B1
Lawrence, MA 01840  USA
Tel: 978 687-1833  ◊  Fax: 978 945-0372

Copyright © 2012 Spectral Evolution, Inc
The SR-3501 and SR-1901 spectroradiometers can classify continuous solar simulators to IEC
and ASTM standards. The SR-1901PT classifies pulsed solar simulators. The DARWin SP Data
Acquisition software provides reports for measuring the simulator's ability to meet class
Solar simulators allow for the accurate testing of solar cells,
modules and panels to measure their conversion of light to
electric current. There are two types of solar simulator:
continuous and pulsed. Continuous simulators provide a steady
illumination for a longer period of time; pulsed apply a flash type
illumination of shorter duration. Both types are typically
measured for spectral match, the amount of light produced;
spatial uniformity, the consistency of the light output over the
area illuminated; and temporal stability, the consistent output of
light over a defined period of time.

Spectral Evolution's
SR-3501 and SR-1901 provided testing of
continuous solar simulators. The
SR-1901PT tests long and short
pulsed solar simulators.

Temporal stability and spatial uniformity are misnomers - the
appropriate Spectral Evolution spectroradiometer is actually
measuring the non-uniformity of irradiance over the physical
area of the device under simulation and the instability over time
of the irradiance. Measuring temporal instability requires
different measurements depending on whether your simulator is
continuous or pulsed. In addition two parameters are used: short
term instability (STI) and long term instability (LTI).
STI relates to the sampling time of a data set (irradiance, current,
voltage) during an I-V measurement (current-voltage). The value
of temporal instability may be different between data sets on the
I-V curve and in that case the STI is determined by the worst
case. LTI is related to the time period of exposure where the
maximum and minimum irradiance depend on the application of
the solar simulator. If the simulator is used for endurance
irradiation tests, temporal instability is defined by the maximum
and minimum irradiance measured with a detector at any
particular point on the test plane during the time of exposure.

Short term instability of irradiance:
Class A - 0,5%
Class B - 2%
Class C - 10%

Long term instability of irradiance:
Class A - 2%
Class B - 5%
Class C - 10%

The SR-3501 and SR-1901 can meet the requirements for
measuring STI and LTI with a continuous (steady-state) solar
simulator. The SR-3501 has a spectral range from 280-2500nm;
the SR-1901 has a spectral range from 280-1900nm.

For pulsed solar simulators the SR-1901PT has the following
  • 280-1900nm spectral range
  • One silicon photodiode array detector and one InGaAs
    extended wavelength photodiode array detector
  • Factory irradiance calibration to NIST traceable standards
  • Adjustable integration and scan averaging time
  • Internal phototrigger with SMA-905 port
  • 0-100 millisecond trigger delay increment
  • External TTL triggering input port
Measure Your Solar Simulator for Temporal Stability