ILT5000, SPM068/QNDS3/R Research Low-Level Radiance Measurement System

Bench-Top Research Low-Level Radiance Measurement System 

ILT5000 Radiometer, SPM068/QNDS3/R Detector

Part Number: ILT5000 Radiometer, SPM068/QNDS3/R Detector

Bench-Top Research Low-Level Radiance Measurement System 

  • 10 Decade dynamic range of optical analysis
  • 4 - 20 mA output
  • Sample rate up to 100 Hz, programmable
  • Auto-range, Auto-dark, Auto-sample with user control options
  • Built-in wireless transmitter**
  • Built-in rechargeable battery pack
  • "Set it & Forget it" remote data logging
  • Continuous multi-system monitoring
  • Backward compatible with the ILT1700 SED detector/filter/optics
  • Labview compatible
  • NIST Traceable / ISO17025 accredited calibration and certificate
  • Can be configured for custom and OEM applications.  Contact us for details.


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Response Curve

SPM068/QNDS3/R This photomultiplier detector with built-in power supply is fitted with our narrow field of view optic allowing geometrically accurate radiance measurements in very low light level applications such as bioluminescence, phosphorescence, safety marking, and photon counting. The minimum spot size at a 1-inch distance is 25.4 mm in diameter. This detector is not typically recommended for contact luminance measurements due to secondary reflection characteristics. The detector comes equipped with a QNDS3 attenuator to prevent overexposure of the detector but it may be removed for ultra-sensitive light measurements. The detector has two gain modes - high and low - to vary the dynamic range to suit the measurement application. Calibrations in W/cm2/sr with and without the QNDS3 are provided.

Dynamic Range: With QNDS3: 1.37e-11 to 1.37e-4 W/cm2/sr (high gain mode) or 1.69e-9 to 1.69e-2 W/cm2/sr (low gain mode). Without QNDS3: 1.37e-14 to 1.37e-7 W/cm2/sr (high gain mode) or 1.69e-12 to 1.69e-5 W/cm2/sr (low gain mode).

Field of View: ± 0.75 °
Measurement Range: 320-600 nm
Dimensions: 167 mm x 42 mm dia.
Ordering part#(s): ILT5000, SPM068/QNDS3/R

SPM detector
Relative Spatial Responsivity










Please note: Care must be taken not to expose this detector to direct room or sunlight signals with the QNDS3 attenuator removed while the detector is connected to the meter to prevent irreparable damage to the photomultiplier tube.


Filters and input optics are removable and may be ordered separately from the detector assembly to allow filter and input optic swapping.



For the latest meter specifications, data sheet, installation guide, tech notes and software, visit the ILT5000 page here.