Abstract: A position-measuring transformer having a pair of confronting relatively movable supports (12, 14) upon the confronting faces (16, 18) of which lie patterns of conductors is disclosed (26, 50). The conductors (26, 50) on the respective supports (12, 14) are dimensioned, configured, and positioned in such a way that portions of the conductors of one support confront portions of the conductors of the other support. When the conductors of one support are energized, a coupling effect is produced in the conductors of the other support. This coupling effect varies as a function of the relative position of the conductors, i.e., the relative position of the support. The energized conductors comprise a pattern of strip-like conductors (30, 88, 116) placed side by side. The conductors in which the coupling effect is produced are of two configurations. The "fine data" pattern comprises strip-like conductors (116) placed side by side in a pattern similar to that of the energized conductors (30).

Abstract: Apparatus for correcting the error of a position measuring apparatus, the apparatus having a first measuring interferometer path of variable length and a second interferometer monitoring path of fixed length. Means are provided for monitoring the change in the optical path length of the monitoring interferometer due to environmental changes and for reflecting these changes in the indicated measurement of the measuring interferometer.

Abstract: A method for making an improved member of a position measuring transducer is disclosed, wherein the member has a pattern of uniformly pitched bars thereon. The method comprises the steps of superimposing a plurality of positionally shifted latent images of an initial pattern of bars having approximately uniform pitch upon a photo-sensitive material, and then processing the photo-sensitive material to produce a production pattern of bars having a significantly more uniform pitch than the initial pattern. The production pattern is used to produce an improved member of a position measuring transducer having a correspondingly greater accuracy than a transducer incorporating a member made directly from the initial pattern. A procedure for selection of the processing parameters to control the uniformity of spacing between bars and to adjust the width and relative position of the "gray" transition region at the bar edges is also taught. Finally, the production of improved scale members of INDUSTOSYN.RTM.