Multiband photometer

Remote sensing instruments




 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 


Precision and stability of the measurements

      • Most wide-spread  and scientifically validated instrument
      • Many standardized and entirely automatic patterns of measurements
      • Measurements great  stability for long time even in harsh climatic conditions
      • Narrow and strictly specified field of view  

Operating reliability under  any climate

      • Continuous operating even under extreme climatic conditions
      •  Reinforced protection against lightning
      • High robustness and corrosion resistance (more than 10 years lifetime)
      • Reduced regular maintenance
      • More than 600 instruments operating around the world

Flexibility of use

      • Suitable for  long-term installation within observation networks as well as  field  campaignmeasurement
      • Operates without any human attendance in a complete automated way with its own solar generator
      • Communicates either to a PC or entirely autonomously via a satellite beacon


 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

Optical sensor head

      • Includes two detectors in order to cover the entire spectrum from 340 nm to 1640 nm
      • Optical line-of-site channel for each detector with a narrow, strictly-defined field of view (1.3°)
      • Single-band precision filters inserted in the optical path    
      • Motor-driven filter wheel positions each of the nine filters in turn
      • Second motor-driven filter wheel adds polarization filters (in three directions) for  models with polarization
      • Silicon photodiode detectors for the UV and visible spectrum, and InGaAs detectors for IR.
      • Extremely sensitive, low-noise, resistant to changes in temperature
      • A dual external collimator mounted on the head eliminates all stray light.

Precision automated mount

      • CE318 Automated mount

        Two high-resolution driven systems with an original backlash integral adjustment due to a Cimel custom technology
      • High sensitivity tracking system four-quadrant detector 

Control unit

      • Functionnalities  of control, data acquisition and storage and communication  are integrated in a single metallic and hermetic acquisition unit


      •  The  instrument performs preprogrammed tasks several times per day, according to various patterns:

- Direct solar measurements: sun tracking and triggering of a multi-band measurement cycle

- Sky measurements: positioning according to a main plan or to almucantar and triggering of a measurement cycle at several angles in the plan

      • The measurement performed data are  automatically stored by the control unit and  may be transferred in real-time to a local PC over an RS-232 connection (maximal length : 100 m)
      • The control unit can periodically activate a satellite beacon to transfer data during allocated time slots to geostationary satellites (GOES, METEOSAT, GMS, ...)
      • Keyboard-display interface for configuring the instrument and checking operation is available to the users

Technical features





Irradiance precision 

< 0.1% 


Well precisely defined field of view



Minimal scatterring angle (from the sun)


Wide spectral range

340 to 1640 nm standard ( for more, see options)


Optical new technology  filters

Derivation:< 1% / year


Automated mount

2 axis for  whole sky angular scanning(0°-360°, 0°-180°)


Mechanical  precision spot



Solar tracking precision(automatic tracking)


Power consumption

Micro power consumption average

< 2 W

Environmental conditions



-30°C to 70°C

0 to 100% RH


Total weight with support

38 kg


CE318 deployment in Tamanrasset (Algeria)









CE318 deployed




CE318 deployment in polar environment

Optional accessories

Head types

The following heads can be fitted to the photometer according to the application:

Reference Description Filters Applications

318-NE BS9

Standard model with 9 filters

340, 380, 440, 500, 670, 870, 936, 1020, 1640 nm


318-NE DPS9

Polarized model

340, 380, 440, 500, 670, 870, 936, 1020, 1640 nm

Polarization in three directions

Polarized  & non polarized measurements


Measurement of luminance emerging from the water surface

412,440,500,531,550,675,870,936,  1020 nm

Ocean color


BRDF measurements

380, 440, 550, 675, 740, 870, 936, 1020, 1640 nm

Satellite calibration



440, 500, 670, 870, 936, 1020, 1640 nm

Night-time and polar region measurements


CE318 optional accessories 


Sales reference






Heating robot


Robot with built-in heating system


To be used in very cold climates (prevents freezing)


Cold & polar climates

Kit Satellite


Satellite transmission system


Beacon, GPS, antenna, solar powered


Remote sites



Cimel provides  AstpWin inversion software free of charge.

It performs the following:

Acquisition and storage of raw data

Representation of the Beer-Lambert-Bougher law (for calibration purpose)

It also includes an inversion software developed by the University of Granada that produces the  following columnar parameters:   

      • Aerosols optical thickness (AOT) for each wawe length
      • Aerosols volume distribution
      • Automatic detection of clouds repartition and filtering
      • Aerosol size distribution
      • Phase function for each scatterring angle
      • Asymetric parameter
      • Simple scatterring Albedo