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Enviro300 Wide Spectral Range Solar Spectroradiometer

  • Wide spectral range thermally controlled solar spectroradiometer

The Enviro300 may be operated unattended via the BenWin+ software suite, recording spectra as often as every five minutes in some of the most inaccessible environments on earth over extended periods.

The system is based around the compact 600mm focal length DTMc300 (280-2500nm) double monochromator, with photomultiplier detection, detection electronics and a choice of input optics.

Core benefits


  • Windows control software provides full automation via USB 2.0
  • Measurements traceable to Physikalisch-Technische Bundesanstalt (PTB, Germany)
  • Two-stage Peltier cooling (and associated fan) assembly are used to stabilise the temperature
  • The UV irradiance standard of this system is the Bentham CL7 enclosed Deuterium lamp with its associated 708 power supply
  • Full detection electronics suite


  • Solar irradiance monitoring
  • Data input to climate modelling
  • Ozone column and aerosol optical depth measurements

Monochromator Specifications

Optical layout

ConfigurationPair symmetrical Czerny Turner monochromators arranged for either additive or subtractive dispersion
Focal lengthTotal focal length: 600mm (additive)
Individual Units: 300mm
Grating mountTriple grating turret
Number of gratings1-3
Grating size68 x 84mm
Aperture ratiof/4.1 (at all grating angles)
Number of entrance/ exit ports1 or 2 in both monochromators


Mechanical resolution drive0.000072°/ step
Slit typeFixed, micrometer or motorised variable
Slit width & height10µm-10mm (W) x 20mm (H)
Filter size23/25mm diameter

Optical performance (quoted for 1200 g/mm grating)

Spectral rangeWithin range 200nm-50µm
Linear dispersion1.35nm/mm (additive)
Wavelength accuracy± 0.1nm
Wavelength reproducibility± 0.025nm
Resolution full/reduced slit height0.15/0.05nm
Stray light rejection at 2.5 FWHM10-8
Wavelength acquisition speed2000nm/s


Computer interfaceUSB 2.0
Software controlBenWin+ / SDK

Electrical / Mechanical

Overall dimensions 634L x 360W x 211H (mm)
Optical height 115mm
Weight28 kg
Power supplyMains input 110/220V 50/60Hz

Operational set-up

Wavelength rangeComponentsBandwidth
280-400nmPMT, 2400g/mm0.5
400-600nmPMT, 1200g/mm1
600-1100nmSilicon, 1200g/mm5

Envirobox Specifications

Mechanical & Interface

Thermal control- Insulated via high density polystyrene walls
- A two-stage Peltier cooling (and associated fan) assembly stabilise the temperature
Electrical and USB connections- Electrical connection to the elements inside the Envirobox is facilitated via a distribution board fed from an external environmentally sealed plug
Fibre bundle connection- Light is transported from the input optics by a 10m quartz fibre bundle

Input Optics

Direct solar accessoryFibre-coupled
Two integrating spheresFibre-coupled


Bi-alkali photomultiplier tube (PMT)(200-~650nm) Requires 215 modular high-voltage PSU
Silicon detector(250- 1100nm)
Lead Sulphide (PbS)(~800-~3000nm)

Calibration standards

CL6UV-vis-IR 150W quartz halogen irradiance standard, requires 610 PSU
CL7UV deuterium irradiance standard, requires 708 PSU
CL_HgUV-vis-IR 1KW irradiance standard (Refer to Gigahertz Optik documentation.)
*two adaptor plates are provided for attachment of the input optics 

Detection electronics

417Detection electronics sub-rack, power supply and display
462Relay module
467DC current amplifier
215High voltage supply
496Lock-In amplifier
418MChopper control electronics
CPS1MPeltier cooler power supply


Enviro150DMc150 monochromator for narrow range measurements; 280-600, 300-1100nm
Enviro300DTMc300 for wide range measurements 280-2500nm
GlobalDiffuser on Rotating Shadow Band with no shadow
DiffuseMeasurement of diffuse solar irradiance, using rotating shadow band
Diffuser on RSB with shadow
DirectMeasurement of direct solar irradiance with direct solar accessory and solar tracker
Alternate fibre input, e.g. from telescope on sun tracker for direct solar

Ordering information

Enviro_150Spectroradiometer solution featuring DMc150 monochromator for narrow range measurements; 280-600, 300-1100nm
Enviro_300Spectroradiometer solution featuring DTMc300 monochromator for wide range measurements 280-2500nm

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