LASER ARRAYS.

This paper deals with the application of various types of array techniques. The laser is assumed to have a Gaussian field distribution at its aperture, and its far field pattern is developed from this aperture pattern. The linear broadside array factor is applied to both the Gaussian element pattern and to an element consisting of a circular aperture uniformly illuminated with a plane wave. The Dolph-Tchebyscheff and binomial amplitude distribution array factors are applied to the Gaussian element pattern to reduce sidelobe levels with equal element spacing. Ishimarus technique of unequal element spacing is applied to the Gaussian element pattern to reduce sidelobes, and then to supress the secondary beam. The half-power beamwidths are calculated and compared, and the circular array is investigated for application to the Gaussian element pattern. Results concerning relative sidelobe levels and grating lobe levels are tabulated and compared. Conclusions are made concerning the feasibility of applying array theory to lasers with element spacings of hundreds of wavelengths. Author