Optical technologies include shadow, self imaging and interferometric. The corresponding technique is called interferometric microscopy. This technique is called interferometric microscopy. Recent achievements of interferometric microscopy allow one to approach the quarter-wavelength limit of resolution. The technique employed is known as interferometric synthetic aperture radar. Intermap Technologies was the prime contractor for processing the interferometric synthetic aperture radar data. In parallel, the use of interferometric arrays for extragalactic H-I spectroscopy was being developed. This was the largest optical interferometric array at the time. In addition, there are four auxiliary telescopes forming an array used for interferometric observations. KAGRA has two arms, long, which form a laser interferometric gravitational wave detector. It forms the basis of the self-calibration approach to interferometric imaging. A detailed discussion on interferometric autocorrelation is given in several well-known textbooks. This was the first interferometric measurement of any object outside the Solar System. The list includes both single dishes and interferometric arrays. Robert Forward operated an interferometric detector at Hughes in the early 1970s.