The company specializes in metrology products, such as laser interferometers and optical profilometers, which are used to measure surface quality and defects on precision surfaces. Their patented Dynamic Interferometry technology allows for accurate measurement in challenging environments. 4D Technology's products include Fizeau Interferometers, Optical Surface Profilers, Dynamic Laser Interferometers, Imaging Polarimeters, and Snapshot Surface Gauges. These instruments are used in industries such as aerospace, astronomy, and defense to enhance manufacturing processes and increase scientific understanding.