Abstract: A magnetic parking device for retaining an actuator in a disk drive over a landing zone. A magnetically permeable capture member is provided on the drive actuator and a magnetic parking member for capturing and magnetically retaining the capture member to park the transducer is provided adjacent the drive actuator. The magnetic parking member includes a permanent magnet and a magnetic field containing member having a slot (or air gap) formed therein. The magnetic field containing member and permanent magnet form a magnetic circuit with a magnetic flux with the slot in the magnetic field containing member allowing a portion of the magnetic flux to extend beyond the physical confines of the magnetic field containing member to provide a capture region for the capture member.

Abstract: A projection microscope is provided in which light from a light source in the base of the microscope may be directed either up through a specimen mounted on a stage to provide transmitted lighting or obliquely downwardly onto the specimen to provide surface lighting. An objective lens above the illuminated area enlarges the image and focuses it on a projection lens mounted within a fully enclosed housing. Light from the projection lens is reflected by an adjustable mirror either onto the back of a ground glass viewing screen along a first optical axis, or onto a photographic film in a film holder positioned at the top of the housing.

Abstract: A television flaw detector, and process, for inspection of the wall surface of a hole through a circuit board. The circuit board is positioned on a support beneath a microscope, with the hole to be inspected aligned with the microscope. On the opposite side of the circuit board are an optical condenser and a light source. The condenser directs a divergent conical beam of light into the hole to illuminate the wall surface of the hole about its entire circumference and along its full length. A mask prevents non-reflected light rays from passing directly through the condenser and the hole into the microscope. A television camera mounted on the microscope is connected to a television monitor upon which it produces an image of a region of the wall surface of the hole extending from its full circumference at a selected position along its length.

Abstract: A tensile tester for hair strands in which the strand of hair is stretched between two movable members. The first member is supported from a frame by a pair of parallel flat springs, and the second member is cycled back and forth by an electric motor along a linear path extending perpendicular to the flat springs. The first member is locked between a stop and the second member in the initial position and is moved away from the stop by tension applied through the strand of hair as the second member is moved by the motor away from the initial position.