Patent US 9,268,983

Optical system for reading structurally distinct microbeads. The microbeads are encoded and provide output light signals onto a Fourier plane when illuminated by an incident light. The system includes an input light source configured to illuminate the structurally distinct microbeads thereby providing the output light signals. The output light signals are configured to be projected onto the Fourier plane in a readable manner. The system also includes a reading device that is positioned to detect the output light signals from the Fourier plane. The input light source and the reading device are configured to automatically illuminate the microbeads and detect the output light signals in a predetermined manner. The system also includes a processor configured to perform Fourier plane analysis of the output light signals to determine corresponding codes of the microbeads.