Single Particle Soot Photometer – Extended Range

The SP2-XR delivers accurate, size-resolved single particle measurements of black carbon mass and size with real-time, direct output suitable for monitoring applications and field research.


Leverage real-time output of black carbon mass and size for individual particles to support monitoring and field work. Plus, easily synch your data with other environmental monitoring data (weather, criteria pollutants, etc.).

Capture variances in black carbon make-up to enhance model effectiveness with single particle detection.

Simplify your data analysis with Intuitive, streamlined direct output of measured and derived parameters, including mass and particle size.

Target particles critical to primary pollution characterization with incandescent particle detection as low as 50nm.

Easily deploy in field applications thanks to a smaller, lighter package that occupies less space on an aircraft.

Save time and resources with easier calibration, alignment, cleaning, etc. so you can focus more of your energy on research instead of the instrument.

Climate Models & Radiative ForcingHuman HealthPollution Characterization
The SP2-XR's high sensitivity, fast response, and specificity to elemental carbon also make it ideal for measuring soot in snow, ice or water and for calibrating other black carbon-measuring instruments like the Aethalometer.

Laser incandescence and particle light-scattering

  • High optical power intracavity Nd:YAG laser heats light-absorbing particles to the point of incandescence.
  • Single particle incandescence is measured and correlated to black carbon mass.
  • Single particle light scattering is measured and used to indicate particle size, non-BC containing aerosol number, and mass concentrations.
Measured Parameters Single-particle laser incandescence Single-particle light scattering
Derived Parameters Single particle black carbon mass Single particle size distribution for purely scattering particles
Auxiliary Parameters Temperature – Air, Computer, Laser Pressure – Cavity and Flow Controller Flow – Sample and Sheath
Particle Size Range Scattering Channel: 100-500 nm diameter Incandescent Channel: 50-800 nm diameter (Assumes black carbon density of 1.8 g/cm3)
Laser Nd:YAG Laser – 1064 nm, up to 1 MW/cm2 intracavity circulating power
Sample Flow 30-120 standard cm3/min
Computer System Intel i7-6600U CPU 8 GB RAM 128 GB mSATA SSHD
Weight 13 kg (28.5 lbs)
Dimensions W: 20 cm, H: 21.5 cm, L: 40.5 cm, not including inlet hardware and fuses
  • Beam scan camera and software
  • YAG optics kit (spare YAG crystal and output coupler)
  • Laser alignment bench
  • Nebulizer for liquid samples with optional auto-sampler
  • Aircraft Aerosol Inlet

Droplet offers a three-year service plan to ensure that your SP2-XR continues to deliver high-quality data. This plan locks costs upfront at the time of funding application, and covers annual calibration, alignment, cleaning, wear-item replacement, calibration documentation, and shipping. Specific services provided for SP2-XR include:

  • Shipping to and from Droplet facility for service
  • Incoming instrument evaluation and health check
  • Full system leak test
  • Filter check and replacement
  • Laser power and beam image verification
  • Power supply and electronics updates
  • Voltages set and verified
  • Optical cleaning
  • Crystal alignment
  • Laser alignment
  • O-ring replacement
  • Hardware replacement
  • Jet alignment
  • APD alignment
  • Pulse widths, thresholds, and configuration settings updated
  • Flow measurements and coefficients calibration
  • Pump testing
  • PSL sizing and black carbon mass distribution calibration using DMA
  • Ambient distribution evaluation
  • Zero count testing
  • Data processing
  • Software, firmware, and antivirus update
  • 100% unit functionality test
  • Calibration data, Calibration Report, Certificate of Calibration provided

Talk to an expert

Speak with one of our scientists or experts at Droplet Measurement Technologies today to discover solutions that can power your research.

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