Two axes remote mirror mount

In an apparatus to suspend and remotely position a device affixed to a backup plate and cantilevered from a fixed support by at least one V-shaped beam flexure suspension support, said device having at least one preloaded actuating means between said backup plate and said fixed support, the improvement which comprises:

• at least one preloaded differential ball-bearing screw actuating means affixed between said backup plate at a first end and said fixed support at a second end, said ball-bearing screw having a multiplicity of ball bearings encapsulated within an enclosed continuous helical race at both said first and second ends, said helical race at said first end having a different pitch angle than said helical race at said second end to provide differential movement between said first and second ends as said screw is rotated either clockwise or counter-clockwise, each of said multiplicity of ball bearings within said enclosed continuous race are in compressional contact with walls formed by said enclosed continuous race, the compressional force being supplied by said at least one V-shaped beam flexure between said backup plate and said fixed support, the combined deflection of both ball and contact surface of said walls averages out any error introduced into said apparatus between the multiplicity of balls which provides an adjustment precision of the backup plate with respect to said fixed support of about 0.5 .times. 10.sup.-6 in.