Dear Lu Ling,

Your question is rather cryptic. It sounds like you would like to use a laser scanner from the Riegl company to measure haze. However, this company produces many different instruments, so you should specify which one you would like to use, and preferably explain its main characteristics, especially the operational wavelength.

Then what exactly would you like to measure about haze? Its presence? Its optical thickness? The number distribution, size and shape of the particles? Do you wish to distinguish between water- and mineral-based particles? Do you care about the haze's chemical composition? Or are you perhaps more interested in identifying and characterizing objects that are concealed by haze? What is your ultimate motive or application?

You will need to study the theory of radiation transfer in turbid media, such as clouds, aerosols, fog, etc., as background to your investigation and use of such an instrument. There is an ample scientific literature, including lots of textbooks, articles, presentations and web sites on this vast topic.

Please sharpen your question: this will greatly help colleagues to provide hints and suggestions, and also help you in ensuring you collect comments that are actually relevant to your problem

Regards, Michel.

Dear Michel,

Thank you for your reply!

 The instrument I use is the  Riegl LMS_Z420i.The laser wavelength is in the near infrared wavelength 1550nm. The spot diameter is 0. 25 mrad (In the range of 100 meters,the beam spot is 25 mm), the angular resolution is 0. 002 5 °.

  Now I mainly measure the number distribution, size and shape of the particles,  the exact composition of particles is not sure.I don't know the accuracy of the measurement data, I think if I can find some reference data.Because  this instrument is mainly used for range scan, the  point only have the coordinates, intensity, range, theta ,Phi and RGB parameter.These parameters is not much use to my research,so I was wondering if I can study some of the other content, finding an index to distinguish the composition of the different point I have measured.

May I ask you wha tarticles I could read to solve my problem?

Looking forward to your reply!

Sincerely,

Lu Ling

Dear Lu Ling,

Thanks for your response: your project becomes clearer. For general background information, you can turn to Wikipedia which has a number of relevant articles:

https://en.wikipedia.org/wiki/Light_scattering

https://en.wikipedia.org/wiki/Rayleigh_scattering

https://en.wikipedia.org/wiki/Mie_scattering

As you will see, the amount of light scattering depends both on the number density, nature and size (as well as shape) of the particles, and on the wavelength of the radiation. You will find very many documents on these issues freely available on the Web.

Since your instrument works at 1550 nm, you may also find the following articles of interest:

http://www.ece.mcmaster.ca/~hranilovic/woc/resources/local/spie2000b.pdf

http://cdn.intechopen.com/pdfs/30925.pdf

I hope this helps as a starting point.

I also have one further question regarding your previous message: what do you mean by "RGB" since your instrument only operates at a single wavelength?

Regards, Michel.

Dear Michel,

Thank you very much!Thank you for recommending  me to these articles, they will help me a lot.

The RGB value was acquired by the  pictures which was taken by the  instrument's own camera, then take the image as the background ,assign automatically of the scanning spots.It seems that this value is not relevant to my research purpose.

Sorry,my English is not very good!

Cheers and have a good day.

Sincerely,

Lu Ling