Abstract: An apparatus for positioning an operational member, particularly for use in an optical laser system for optically trapping and manipulating microscopic particles in a particle manipulation chamber. A flexure member, is provided which has a pair of substantially inflexible parallel members and four sets of flexible spring members. The pair of parallel members is maintained in a spaced relationship by the four sets of flexible spring members. Each of the four sets of flexible members has at least two parallel flexible elements which can be leaf springs or formed as a unitary part of the flexure member. The four sets of flexible spring members are in two groups of two flexible spring members with each of two of groups of flexible members having their two sets of flexible spring members positioned in a "V" shaped pattern. The apices of the "V" shaped patterns are positioned outwardly of each other forming a parallelogram having at least six sides and preferably a parallelogram having eight sides.