Measurement of optical transmission plays an important part in the characterization of materials that interact with light. It is normally applied in assessing glasses, polymers, coatings, thin films, and optical elements. The method assists in revealing the absorption, reflections, or the ability of a material to take in, give back, or permit light to penetrate it under controlled circumstances. Transmission behavior is critical in applications where there is a need to be knowledgeable about the behavior of transmission. The measurement is normally carried out in the ultraviolet, visible, or infrared areas based on the material and the reason for its use. Optical transmission analysis is a common element of laboratory work as well as industry quality control due to its reliability and simplicity.
Principle and Methodology
Optical transmission measurement is a principle that is founded on the comparison of the intensity of incident light and the intensity of light that passes through a sample. A controlled light source produces radiation to the specimen, and a detector measurement is taken to detect the signal applied to the material. The percentage of light transmitted is given as a ratio of the light transmitted to that which was incident in the form of a percentage or transmittance. The measurement typically depends on wavelength, which gives a detailed spectral study. Samples are made with the same thickness and put in the optical path to maintain the same results. Instrumental errors also need to be reduced by calibration with reference standards to ensure the accuracy of measurements.
