IMAP100

Advanced particulate characterization: the Inverse multi-angle Polarimeter

The IMAP100 (Inverse Multi-Angular Polarimeter) Nephelometer measures polarized scattered light at multiple angles and at multiple wavelengths. As with our other instruments, we use our feedback flow control system to collect data at multiple size bins ranging from PM1 to PM10. Owing to the small size of the sampling chamber and the overall efficiency of the system, this allows us to determine a full particle size distribution within a span of just 5 minutes. This advanced instrument collects a huge amount of data thanks to its cutting-edge technology: 3 wavelengths x 7 angles x 2 polarization orientations x 4 size bins.

We highly suggest using IMAP100 for an in-depth understanding of particulate properties. Given its unique combination of aerodynamic and optical sizing, it can be used to effectively connect satellite and ground-based measurements for comprehensive air quality research. To manage all of this detailed information, we use a sophisticated GRASP data retrieval algorithm which allows us to accurately determine: particle mass, size distribution, scattering phase function, polarization phase function, real refractive index of the particles, sphericity factor of the particles.

  • Instrument size: 86 × 38 × 32 cm
  • Inlet height: 110 cm
  • Number of measurement channels: 3

  • Inlet / flow rates options:
    • Option A – Alaric AE10-2 cyclone: 2–16 LPM. Preferred for less polluted regions where higher collection efficiency is needed for larger particles.
    • Option B – BGI SCC 1.829 inlet: 1.5–12 LPM. Preferred for highly polluted environments where the focus is on smaller particles.
  • Operating conditions: 5 to +45 °C; 10–95% RH
  • Wavelengths: (3) 450 nm, 520 nm, and 638 nm
  • Polarization: 2 – parallel and perpendicular to the scattering plane
  • Angular ranges measured: 8 view angles centered at 5° (unpol.), 10.6°, 31.8°, 52.9°, 95.3°, 116.5°, 137.6°, 158.8°
  • Instantaneous field of view: < 7.5°
  • Sensitivity: < 0.1 Mm⁻¹
  • Max scattering coefficient: up to 20,000 Mm⁻¹
  • Accuracy: ≤ 10%
  • Size measurements: independent optical and aerodynamic size measurements
    • Aerodynamic: 4 size bins selected from PM1 to PM10
    • Optical: continuous function from 0.05 to 15 µm (every 1 min)
  • Time resolution: 1 min avg (recommended); 15 sec min
  • Display: built-in touchscreen with real-time data and status indicators
  • Storage: internal hard drive; continuous storage with capacity for ≥3 months of data at 1 min resolution
  • Data access: real-time via USB, Ethernet, RS232, and RS485
  • Calibration: built-in clean reference cycle
  • Gas cal: CO₂ and clean air every 3–6 months
  • Power: AC 120 or 220–240 V (50/60 Hz); 600 W max; 5 A breaker

The IMAP100 can provide complete size distribution measurements every 5 minutes, particle mass, full scattering as well as polarization phase function, real refractive index of the particles and sphericity factor.

We suggest IMAP100 for in-depth understanding of particulate properties. Given its unique combination of aerodynamic and optical sizing can be used to connect satellite and ground based measurements for air quality research.

Can the instrument be connected to sampling manifolds rather than direct air intake (as long as pressure upfront the cyclone does not significantly deviate from ambient pressure)?

Yes the instrument can be connected to manifolds. The instrument can also operate without the cyclone if that is a concern for the user.

Can the flow rate be chosen freely, or is it fixed for a given upper diameter cut-off in the cyclone mounted in the inlet?

The active flow rate of the instrument is limited by its internal blower (fan). If the user wants a flow rate outside the range of our blower, the user can always use an external pump or blower.

Can the instrument also run at low ambient pressure (with potentially shifted flow rate or cut-off range)?

Yes, the instrument can run at lower pressure. Pressure correction may be needed for the aerodynamic behavior of the cyclone or for Rayleigh scattering considerations.

● IMAP100 flyer – IMAP100 datasheet.pdf