A dual input tilt controlled flexure mounted beamsplitter interferometer, comprising: a first plane reflector configured to respectively receive and return a first portioned beam of a source along a first optical path length; a second plane reflector configured to respectively receive and return a second portioned beam of said source along a second optical path length; a resiliently mounted beamsplitter for receiving a beam of radiation from said source so as to provide said first and said second portioned beams; movement means coupled to said resiliently mounted beamsplitter to provide a velocity and position control and/or a tilt control about configured X and Y axes of said resiliently mounted beamsplitter; and dual input control means for providing a controlled feedback to said movement means to enable said velocity and position control and/or a combined tilt control about said configured X and Y axes so as to align one or more predetermined flat surfaces in said interferometer, wherein the velocity and position control and/or said tilt control of said movement means further enables optical path length differences between said first optical path length and said second optical path length that in combination provide an interrogating interferogram of the input source beam radiation at a configured exit of said interferometer, and wherein said dual input control means comprises a phase tilt control measurement system and a reflected spot tilt control measurement system, wherein the phase tilt control measurement system comprises: a monochromatic emission source providing an output beam, which is directed to the front face of the beamsplitter, a detector collecting recombined modulated light of said monochromatic emission source having an interference pattern, said detector having detection quadrants (31, 32, 33, 34) arranged to direct signals to circuitry (37, 38, 39, 50) configured to use a phase difference in optical signals from the detection quadrants (31, 32, 33, 34) to measure axis tilt, and wherein the reflected spot tilt control measurement system comprises: an optical source directed to the beamsplitter; an optical detector; a first optical component configured to focus a beam from the optical source; and a second optical component configured to redirect the beam to be collected by the optical detector. a first plane reflector configured to respectively receive and return a first portioned beam of a source along a first optical path length; a second plane reflector configured to respectively receive and return a second portioned beam of said source along a second optical path length; a resiliently mounted beamsplitter for receiving a beam of radiation from said source so as to provide said first and said second portioned beams; movement means coupled to said resiliently mounted beamsplitter to provide a velocity and position control and/or a tilt control about configured X and Y axes of said resiliently mounted beamsplitter; and dual input control means for providing a controlled feedback to said movement means to enable said velocity and position control and/or a combined tilt control about said configured X and Y axes so as to align one or more predetermined flat surfaces in said interferometer, wherein the velocity and position control and/or said tilt control of said movement means further enables optical path length differences between said first optical path length and said second optical path length that in combination provide an interrogating interferogram of the input source beam radiation at a configured exit of said interferometer, and wherein said dual input control means comprises a phase tilt control measurement system and a reflected spot tilt control measurement system, wherein the phase tilt control measurement system comprises: a monochromatic emission source providing an output beam, which is directed to the front face of the beamsplitter, a detector collecting recombined modulated light of said monochromatic emission source having an interference pattern, said detector having detection quadrants (31, 32, 33, 34) arranged to direct signals to circuitry (37, 38, 39, 50) configured to use a phase difference in optical signals from the detection quadrants (31, 32, 33, 34) to measure axis tilt, and wherein the reflected spot tilt control measurement system comprises: an optical source directed to the beamsplitter; an optical detector; a first optical component configured to focus a beam from the optical source; and a second optical component configured to redirect the beam to be collected by the optical detector. an optical source directed to the beamsplitter; an optical detector; a first optical component configured to focus a beam from the optical source; and a second optical component configured to redirect the beam to be collected by the optical detector.