Optical Radiometer


                                         OPTICAL RADIOMETER 
                               
                                This instrument measures in situ spectral
                                iradiance (Watts/m.sq/nm) in the ocean. 
                                Using two spectograph makes it possible to
                                measure upward and downward irradiance si-
                                multaneously as a function of wavelength 
                                dapth and time.
                            
                                With this data we can learn about
                                 * Colour of the ocean and its relation 
                                    to constituients in the medium.
                                 * Spectral attenuation charecteristics of
                                    different ocean waters.
                                 * Model optical properties in terms of 
                                    total chlorophyll concentration.
                                 * Raman emiission and flourescence 
                                    effects in the ocean
                                
                                 The developmant of the Radiometer has 
                                 been funded by the United Natons Development
                                 Programme in collabration with the Govt.
                                 of India(1989-1992)

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SPECIFICATIONS
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OPTICS      : Spectral range 350-750 nm;focal ratio bandpass 2 nm @ 50 
               microm slit

ELECTRONICS : Supervisory CPU for control; slave CPU for spectral 
               acquisition;16 bit analog to digital converter

SENSOR      : Light detector    : 512 pixel photodiode array
              Depth range       : 500 metres
              Accuracy          : 1% full sscale
              Tilt range        : 45 deg.
              Resolution        : 1 deg.
              Temperature range :2 to 40 deg.C accuracy

FEATURES    : Modular design and high resolution
              Up and downward irradiance
              Graphic display of spectra
APPLICTION  : Ocean optics, primary production
              Water quality measurements