Aerosol Measurement & Sunphotometer

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This high-precision photometer for observing networks measures the optical properties of the atmosphere ( sun, sky, moon and soil reflectance) and provides quantification and physical-optical characterization of the aerosols.
Due to its very low power consumption (MicroAmps®) technology, to its self-powered system and to its most rugged design , the CE318 fully meets the operational requirements of continuous monitoring in terms of reliability, long lifetime and very low maintenance cost .
The CE318 photometer technology is constantly enhanced to match the new technological challenges for climate observation and monitoring . The "Cimel" is still the benchmark device for most aerosol observing networks and more specifically for the international federation of AERONET networks.


The CE318 carries out raw measurements according to automatic standardized patterns: sun and sky radiance on several bands as well at day time as night time (CE318-U LUNAR) Raw measurements can be automatically post processed to obtain several atmospheric parameters like aerosols size distribution and their optical properties as well as vapour water quantity.

The large range of produced parameters makes the CE318 photometer a worlwide benchmark device for the following applications:

  • Characterization and quantification of aerosols
  • Satellite calibration of aerosol measurements
  • Detection of volcanic ashes plumes in real time
  • Determination of Aerosol Optical Depth
  • Determination of fine mode and coarce mode AODs
  • Determination of the optical properties of the atmosphere for satellite imaging
  • Determination of the ocean's color
  • Determination of the amount of precipitable water
  • Air quality monitoring

  • MicroAmps® technology

    The CE318 photometer has been designed using all the MicroAmps® technologies that are specific to Cimel, in accordance to very demanding yet complementary requirements:

  • Minimize electrical power consumption
  • Use secure, highly redundant communications protocols
  • Maximize the versatility of printed circuit boards
  • Minimize the number of connectors
  • These MicroAmps® technologies result in CE318 photometer exceptional performances widely proven under any sort of climate, in terms of operating reliability

    Compact Automatic Aerosol LiDAR


    The CE376 is a compact, eyesafe backscatter LiDAR, featuring outstanding performances for the automated continuous monitoring of aerosols.
    It operates in the visible (green) and/or in the near infrared (NIR) with options for depolarization channels for enhanced aerosol characterisation. The rugged, robust, fully integrated system operates without shutdown, without any human attendance,without maintenance, without need for authorization, without a special room, even in harsh environmental conditions It is particularly easy to install, outdoor or indoor, to transport and even to use onboard a vehicle or a plane.


    Measurement principle

  • The laser emits a light pulse that is scattered by the particles present in the atmosphere
  • A tiny part of the pulse light is directed backward towards the instrument (backscatter)
  • The time of flight of the pulse between emission and reception indicates the distance of the scattering particles
  • The amount of backscattered light received at each distance depends on the quantity and type of the particles
  • The depolarization reception channel measures only the light that has been depolarized, indicating the presence of non spherical particles
  • In aerosol free regions, the light received measures the "molecular" backscatter (due to the clean atmosphere molecules)


    Model Name Description

    Detection of non spherical particles

    (ashes, sand, cirruses…)
    Information on vertical distribution of particle size
    CE376-G Green (532 nm) - -
    CE376-GP Green with depolarization YES -
    CE376-N NIR (invisible) - -
    CE376-NP NIR with depolarization YES -
    CE376-GN Green + NIR - YES
    CE376-GPN Green with depolarization + NIR YES YES

    Eye safe LiDAR for 24/7 aerosol and cloud monitoring up to the stratosphere The CE370 LiDAR provides continuous high performance measurements of aerosol and cloud spatial distribution on an extended range. It features a large (200 mm diameter) aperture for enhanced measurement up to high altitudes while ensuring compliance with eye safety rules, and includes a second reception line to extend measurement towards very low altitudes (from 50 m). Robust and reliable, the CE370 operates without shutdown, and requires no human attendance, no maintenance, no authorization, no special room. It may be operated in fixed mode (indoor or outdoor with enclosure) within an observation network, or in campaign mode, fixed or even on a mobile vehicle.


    The CE370 LiDAR provides key parameters like vertical aerosols and clouds distribution as well as boundary layer heights for the following applications:

  • Volcanic ash watch
  • Sand dust storm watch
  • Air quality monitoring and forecast
  • Climate change
  • Airport flight operation
  • Atmospheric sciences
  • Aerosol and cloud modeling
  • Numerical Weather Prediction (NWP)


    Enhanced measurement performance

  • Aerosol detection up to the stratosphere (typically higher than 24 km by night time)
  • Direct measurements of the reference (532 nm) optical properties
  • Very short blind zone ( <50 m)
  • Automatic calibration of extinction (on molecular signal)
  • Real time analysis

  • Automatic extinction and backscattering profiles
  • Automatic calibration of aerosol concentration by coupling with CE318 photometer
  • Automatic stratification analysis
  • Real time "quicklook" visualizations
  • Enhanced reliability

  • 3 year operation without technical maintenance
  • Low maintenance cost
  • High stability even in outdoor operation (from -20°C to +45°C with optional thermal enclosure)
  • High flexibility of implementation

  • Eye safety compliance with EN-60825/ANSI Z136 (no need for airplane detection RaDAR that automatically shuts down the laser)
  • Automatic unattented operation
  • Easy transportation
  • Outdoor/indoor/mobile operation
  • Compliance for airborne operation

    The CE370 is composed of a control unit (housing the laser and acquisition units) connected to a separated optical head system through 10 m long optical and electrical wires Laser

  • 3 year life time without any maintenance
  • Integrated output power monitoring
  • Optical head system

  • Galilean type optical heads
  • Large (200 mm) diameter for enhanced range
  • Long focal length (1 m) for enhanced range
  • Real mono-axis optical design: ensures perfect alignment of emission and main reception
  • The low layer optical head(reception only), mounted on the front side of the main optical head, ensures measurements at very low distances (from 50 m)
  • The two optical heads are watertight and may be exposed to oudoor conditions
  • Acquisition unit

  • Detection in photon counting mode through a high quantum efficiency (QE), high counting rate avalanche photodiode