Go Down

Topic: Refractometer using arduino (Read 1 time) previous topic - next topic

PuneetJindal

hi all,
This is my first post, hope you are able help
I m trying to make a refractometer to measure different concentrations of emulsions.
What i have done so far is :
laser light is being passed to an LDR
in between i place samples of different concentrations of emulsions.
there is variation in the resistance on LDR.
but the consistency is not there the variance shown is different at different times. probably the light from laser is not consistent.
Please help and ask questions if my problem statement is not clear.
TIA

TheMemberFormerlyKnownAsAWOL

#1
Dec 25, 2019, 02:26 pm Last Edit: Dec 25, 2019, 02:26 pm by TheMemberFormerlyKnownAsAWOL
Do you have an unimpeded path for a reference beam?
You should be measuring the source intensity directly.
Please don't PM technical questions - post them on the forum, then everyone benefits/suffers equally

jremington

Do you intend to measure absorbance, or refractive index?

MarkT

A refractometer measures refraction.  You seem to have a photometer.  What laser source are you using?  Is it output constant?  Why aren't you using a linear optical detector like a photodiode?  LDRs aren't linear and don't respond to total photon flux (varying distributions over the sensor area will cause different readings).
[ I will NOT respond to personal messages, I WILL delete them, use the forum please ]

PuneetJindal

Do you intend to measure absorbance, or refractive index?
Hi there
I intend to distinguish two different samples of emulsions, or different concentrations of Oils

MarkT

That wasn't the question.  What are you trying to measure? Refractometer implies refractive index, not absorbance.  https://en.wikipedia.org/wiki/Refractometer
[ I will NOT respond to personal messages, I WILL delete them, use the forum please ]

Go Up