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One can geometrically engineer supersymmetric field theories theories by placing D-branes at or near singularities. The opposite process is described, where one can reconstruct the singularities from quiver theories. The description is in terms of a noncommutative quiver algebra which is constructed from the quiver diagram and the superpotential. The center of this non-commutative algebra is a commutative algebra, which is the ring of holomorphic functions on a variety V . If certain algebraic conditions are met, then the reverse geometric engineering produces V as the geometry that D-branes probe. It is also argued that the identification of V is invariant under Seiberg dualities.

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A closed-form solution of describing perceived image in stereoscopic imaging systems with radial recording and projecting geometry for arbitrary viewer positions is presented. This solution is derived by finding a condition for making the heights of homolog points in both left and right images projected on the screen in the geometry equal. The solution has the same equation form as that of the parallel geometry except that it has a constant shifting term in the horizontal direction. This term is a main source for distortions in the perceived image. The condition of eliminating the term makes the solution the same as that for stereoscopic imaging systems with parallel recording and projecting geometry.