Vol. 6, Issue 1, Part A (2024)

This research was conducted to determine changes in the polarization angle in variations of brake fluid using the polarization method. This research was carried out using brake fluid samples with codes DOT-3, DOT-4, and DOT-5.1. The light source used is laser pointer with wavelengths of λ = 532 nm and λ = 650 nm. In this study, changes in the polarization angle were measured in brake fluid samples. The results showed that all samples had two asymmetric axes at polarizer angles of 30° and 60°. Assuming all brake fluid samples are equivalent to synthetic oil, a uniform molecular size is obtained which is indicated by the almost the same active optical properties of the two samples. This method can be further developed as an evaluation of the quality of brake fluid and similar samples.