A simple optical sensor for the measurement of dry rubber content in natural rubber latex

In this article, we report a new method to measure dry rubber content (DRC) in natural latex using a light scattering principle. Latex collected from the field, without diluting or any other chemical processing, can be directly used in this technique to measure its DRC. A laser beam transmitted through a thin column of latex is imaged using a digital camera and the image is processed to calculate the strength of scattering. We have observed a linear relationship between the DRC of the latex and the full width at half of the maximum of the laser beam intensity profile. The method requires only a very small quantity (about 0.5 g) of latex and the measurement is very fast, taking only a few minutes. Although we have demonstrated the described method for latex characterisation, this method can be extended for turbidity/particle concentration measurement of any heavily scattering liquids.