Optical Sensing Technique Investigation for Preservative Latex Measurement

This paper presents an initial preservative latex measurement technique based on optical sensing. The previous technique used is based on laboratory method, which is the sample of latex need to undergo several laboratory experiments to determine the percentage of Dry Rubber Content (DRC) in a 100g sample of latex. Present-day, there is no portable technology available in the market that can be used to differentiate the electrical properties for the different rubber clones based on latex that can be used for in situ testing. By developing a portable device prototype, it will help farmer and agriculture officer to identify latex clone produced by the rubber tree. This project uses Near Infrared of 880nm and phototransistor of 900nm as signal transduction. The output from signal transduction circuit will go through three (3) stage amplification using two (2) types of LM358 and INA122P operational amplifier. After amplification, the signal will enter the Peripheral Interface Controller (PIC) and the output voltage from the testing process will be displayed. The tests conducted to obtained electrical properties of 30ml Latex 2008 sample are divided into three (3); that are initial testing, dilution test, and reproducibility test. The results obtained are tabulated in Microsoft Office Excel and the data produced are analyzed. As the dilution volume increased, the voltage produced decreased.