Abstract: A method (200) for determining various bit failure modes in a static random access memory device. A hard/soft bit failure test sequence is performed on each cell of the memory device to determine whether the cell exhibits a hard bit failure or a soft bit failure, then a data retention test is performed on the cell having soft bit failure to determine whether the cell exhibits a data retention failure. A write or disturb test sequence is then performed on the cell not having data retention failure, and a read or disturb test sequence is performed on the cell having write or disturb failure. Finally, a disturb test sequence is performed on the cell having read or disturb failure, and then an analysis is performed on the data from the tests to determine whether the cell exhibits one of a write, read, or disturb failure.

Abstract: Apparatus generating a line of light includes a light source, such as an incandescent lamp. A condensing lens is interposed between the lamp and the receiving end of an optical fiber cable for applying the light of the lamp to the cable. The discharge end of the optical fiber cable is flattened into a linear configuration, one or a few fibers thick. The discharge end of the optical fiber cable is coupled to a light beam projector containing a lens focusing and projecting a plane of light. The plane of light forms a line when applied to a patient or other object. A plurality of optical fiber cables and projectors may be coupled to the lamp to provide a pattern of lines.

Abstract: An indicator for indicating a dimension of an X-ray beam defined by a collimator has a base member positioned on the other side of the patient from the X-ray beam source. A pair of light sources are mounted on the base member for linear movement and for angular movement so that the beams of light may be positioned into congruency with the edges of the X-ray field defined by the collimator and converge at the source of the X-ray beam. The light sources may be moved by a cable having selectively movable segments to which the light sources are attached or by lead screws.

Abstract: An indicator for visibly defining the image plane located at the movable fulcrum of a tomography X-ray machine. The indicator includes a laser beam light source mounted for vertical movement along a rack and pinion assembly. As the fulcrum of the X-ray machine is raised or lowered with respect to the patient to take X-ray images along different horizontal planes, a pulse generator generates a signal responsive to the movement. The signal operates a servo-drive mechanism that moves the light source a corresponding vertical distance along the rack and pinion assembly.

Abstract: A device for producing at least one beam of light having a desired configuration includes a source (12) of concentrated light. A fiber optic conductor (18) transmits the concentrated light to one or more locations remote from the source. Light beam forming means (22) receive the light from the fiber optic conductor (18) and form same into one or more beams of light having the desired configurations, such as a plane.

Abstract: An indicator for defining the relationship of a radiation beam to an object, such as a patient or associated apparatus, for example an X-ray film holder. The indicator includes a light source establishing a first light plane containing the beam and appliable to the object. A second light source establishes a second plane of light to contain the radiation beam or object. The intersection of the beams of light defines the radiation beam-object relationship.

Abstract: A device for positioning the spinal column of a patient with respect to exposure control devices behind a chest X-ray film sheet has a light source generating a plane of light bearing a fixed relationship to the exposure control devices. The plane forms a luminous line on the patient when the patient steps in the path of the plane which may be used for positioning as by placing the patient's spinal column along the line. The other planes of light may be used to define the edges of the X-ray film sheet.

Abstract: A patient orienting device accurately positions a patient with reference to a source of diagnostic or therapeutic radiation. The planes of light are appliable to the body of the patient and correspond to the sagittal, frontal, and transverse planes of the body. The device includes a first light source establishing a first light plane lying in the sagittal plane. The first light source is typically located at the foot of the patient. A second light souce establishes second and third mutually perpendicular planes of light. The second light source is typically located at the head of the patient. The light source is positioned so that one of the light planes is co-planar with the first light plane and so that the other light plane lies in the frontal plane. A third light source establishes fourth and fifth mutually perpendicular planes of light. The third source lies on one side of the sagittal plane so that the fourth and fifth light planes intersect the first light plane normal to the latter.