Optical detection is a research area that involves the use of optical techniques and instruments to detect and analyze various substances or events. This can include the detection of biological molecules, environmental pollutants, chemical compounds, and physical properties such as temperature or pressure. Optical detection typically relies on the interaction of light with the target substance or event, and may involve techniques such as absorption spectroscopy, fluorescence spectroscopy, or light scattering. Optical detection is widely used in fields such as environmental monitoring, medical diagnostics, and materials science, and continues to be a valuable tool for researchers and scientists in many disciplines.