Recording head and support arm for stretched surface recording medium

Claim 1

A recording head and support arm assembly for positioning a recording head in proximity to a rotating stretched surface recording disk having at least one thin film tensioned on a supporting substrate, said head and support arm assembly comprising; a magnetic transducer head including a spherical surface adjacent said thin film having a spherical radius numerically equal in units of inches to 4/3 the tension, plus or minus 20 percent, of said film expressed in units of pounds per inch, wherein tension is defined as film stress in units of pounds per square inch multiplied by film thickness in units of inches; a series of parallel grooves in said spherical surface and aligned with the direction of relative movement between said head and said thin film, said head including a recording core disposed substantially at said spherical surface such that said grooves are symmetrically positioned with respect to said core, said head extends transversely to said direction of relative movement between said head and said thin film; and a support arm mounting said head and resiliently biasing said head toward said thin film, said arm resisting movement of said head in the direction of relative movement between said head and said thin film and permitting limited rotational movement of said head relative to said thin film about an axis parallel to a radius of said disk intersecting said head and an axis parallel to said direction of relative movement between said head an said thin film, said support arm thereby maintaining said head grooves parallel to said direction of relative movement between said the ad and said thin film while permitting rotative movement of said spherical surface relative to said thin film.