In October 2018, it was announced hat 4D Technology had been acquired by Milpitas, CA based Nanometrics (NASDAQ:NANO). 4D Technology Corporation designs and manufactures laser interferometers, surface roughness profilers, and interferometry accessories for the measurement of optics, optical systems, and precision machined surfaces. It offers AccuFiz, a compact laser interferometer for shop floor quality control and verification of optical components and systems; and PhaseCam interferometers for measuring large diameter mirrors and optical systems in environments, such as vacuum chambers, over long measurement paths, and adaptive optics. The company also provides NanoCam Sq, a portable microscope-based optical profilometer for measuring surface roughness of large and small optics, and nano-topology of precision components. In addition, it offers FizCam laser interferometers for measuring large flats, remote cavities, and multi-surface systems; and 4Sight data analysis software for data analysis, transformation, and visualization. Further, the company provides PolarCam micropolarizer cameras to capture multiple polarized images of video frame by enabling a range of image enhancement techniques; custom solutions; and 4D upgrade kits. Its products are used in astronomy, aerospace, data storage, optical testing, paper and article, real world test setup, flats, wedge, homogeneity, transmitted wavefront, prisms, corner cubes, spheres, 3D surface roughness of polished optics, image enhancement, medical imaging, 3D reconstruction, glare reduction, haze removal, birefringence mapping, industrial monitoring, and polarization microscopy applications.