Head clamping apparatus for magnetic disk tester and magnetic disk tester

A magnetic disk tester comprising:

• a coarse stage having a head load mechanism on which a head clamp is installed, the head clamp holding a piezo-stage which holds a magnetic head assembly, a reflective scale made of a film being disposed on a back face of the piezo-stage, and light-shield stripes being deposited on the film at regular intervals;
• a laser head attached to the coarse stage having a light emission/reception part facing the light-shield stripes of the reflective scale;
• and
• positioning means for controlling the position of the head clamp,
• the laser head emitting a laser beam, the reflective scale reflecting the emitted laser beam, the positioning means detecting the position of the magnetic head assembly on a magnetic disk according to the reflected laser beam and controlling the position of the head clamp according to an error signal which indicates the difference between the detected position and a reference position.

A head clamping apparatus for a magnetic disk tester, movably supported by a linear coarse stage and comprising:

• a linear micromotion stage attached to a head clamp and configured to hold and move a magnetic head assembly in a direction crossing a moving direction of the coarse stage;
• a reflective scale attached to a back face of the micromotion stage, having light-shield stripes formed at regular intervals;
• a laser head attached to the coarse stage and having a light emission/reception part facing the light-shield stripes of the reflective scale;
• and
• positioning means configured to control the position of the head clamp,
• the reflective scale reflecting a laser beam emitted from the laser head, the positioning means detecting the position of the magnetic head assembly on a magnetic disk according to the reflected laser beam and controlling the position of the head clamp according to an error signal which indicates the difference between the detected position and a reference position.