Abstract: An optical drive system includes an optical assembly, a light source capable of transmitting light through the optical assembly, an objective lens positioned to direct light between the optical assembly and a respective information storage medium, and an actuator suspending the objective lens for relative motion thereof with respect to the actuator. A photodetector is disposed in a path of returning light to measure return light received from the respective medium. A monitoring circuit is provided to monitor a Quad Sum signal associated with the return light. A first servomotor is employed to move the objective lens in a tracking direction relative to the actuator and to move the objective lens during focus capture relative to the respective medium being read while system circuitry searches for a maximum Quad Sum signal. A second servo motor is employed to move the objective lens in a focusing direction relative to the actuator assembly.

Abstract: An apparatus for controlling a magnetic field strength of a bias coil at a focal point of a lens during recording on a medium. The apparatus includes a first controller for determining a distance between the focal point of a lens and a reference point on the recording media. A source generates a stray magnetic field having a stray field strength at the focal point. A second controller calculates a digital signal which is a function of the distance and the stray field strength. A digital-to-analog converter converts the digital signal to a driver voltage and passes the driver voltage to a current driver, which drives the bias coil. The magnetic field strength of the bias coil is thereby controlled at a predetermined value.

Abstract: There is disclosed a method for moving an optical head from an initial track to a target track on a storage medium. The total number of tracks to be crossed is determined, and the optical head is moved toward the target track. A reflectivity level of light from the storage medium is measured, and a tracking error signal is derived from the reflectivity level. The tracking error signal has both true and false indicators of track crossings. A data indicator signal is derived from the reflectivity level, having indicator points corresponding to the false indicators of track crossings. A track count number is incremented for each true indicator of a track crossing, and the optical head is stopped when the track count number equals the total number of tracks to be crossed. Another method is disclosed whereby a track count signal is generated from the tracking error signal and the data indicator signal.

Abstract: A flexible strip test cable is disclosed having an elongated flexible strip cable, a series of strip traces disposed lengthwise on the flexible strip cable and having electrical strip contacts near one end of the flexible strip cable, an extension cable integral with the flexible strip cable and having a width at one end greater than the width of the flexible strip cable, and a series of test traces on the extension cable having electrical test contacts near the end of the extension cable remote from the flexible strip cable. Each of the test traces is electrically connected to one of the strip traces, and the minimum distance between two test contacts is greater than the minimum distance between two strip contacts. The flexible strip test cable may have a tooling guide for aligning a cutting tool with the end of the flexible strip cable which is connected to the extension cable.

Abstract: There is disclosed an apparatus for controlling the strength of a magnetic field, comprising a first controller, a second controller, a digital-to-analog converter, a current driver, and a bias coil. The first controller determines the position of the focal point of a lens and passes it to the second controller, which provides a digital signal related to the position. The digital-to-analog converter converts the digital signal to a driver voltage and passes the driver voltage to a current driver, which provides to the bias coil a bias current related to the driver voltage. The bias coil produces a magnetic field having a strength related to the bias current. The second controller accounts for stray magnetic fields in creating the digital signal. The stray magnetic fields may be constant or may vary in strength based on position of the objective lens, circumferential velocity of the storage medium, or longitudinal velocity of the storage medium.

Abstract: An apparatus for moving an optical head from an initial track to a target track on a storage medium and generating a track crossing signal is disclosed. The apparatus comprises a sensor for measuring the reflectivity level from a storage medium, a preamplifier for generating a data signal, a tracking error signal generator responsive to the reflectivity level for deriving a tracking error signal, a track/hold selector to direct the tracking error signal generator to generate a corrected tracking error signal of a constant amplitude for a predetermined period of time based on the data signal, and a track crossing signal generator based on the corrected tracking error signal for deriving a track crossing signal indicating the crossing of an information track by the optical head.

Abstract: There is disclosed a method for moving an optical head from an initial track to a target track on a storage medium. The total number of tracks to be crossed is determined, and the optical head is moved toward the target track. A reflectivity level of light from the storage medium is measured, and a tracking error signal is derived from the reflectivity level. The tracking error signal has both true and false indicators of track crossings. A data indicator signal is derived from the reflectivity level, having indicator points corresponding to the false indicators of track crossings. A track count number is incremented for each true indicator of a track crossing, and the optical head is stopped when the track count number equals the total number of tracks to be crossed. Another method is disclosed whereby a track count signal is generated from the tracking error signal and the data indicator signal.

Abstract: A class of predominantly hydrophobic non-azo N-substituted 1,8-naphthalimide compounds, each bearing, at its 3-position, a nucleofuge and, at its 4-position, a heteroatomic electron-releasing group. The heteroatomic electron-releasing group is being characterized as having a heteroatom directly linked to the 4-position of the ring, and having at least one hydrogen directly attached to the heteroatom. Upon activation by an activating agent in an environment independent of the presence or absence of oxygen, these compounds generate activated species. The activated species initiate chemical changes in lipid bilayer membranes of viruses and other target cells. These changes can eradicate viruses and other target cells. The activated species can also cause structural changes in lipid and any associated proteins and polypeptides at a level beneath the surface of the membrane, leading to polymerization and crosslinking.

Abstract: A method for the qualitative or quantitative determination of the deleterious agent in a substantially non-aqueous medium, such as an oil. The method involves using a non-azo 1,8-naphthalimide dye for the detection or quantitation of the total hydrogen ion activity in a substantially non-aqueous medium. The method includes the steps of: Mixing the dye with the substantially non-aqueous medium, which may or may not contain any hydrogen ion, to form a mixture; irradiating the mixture with a fluorescent light sufficient to cause the mixture to emit a detectable fluorescent emission spectrum; detecting the fluorescent emission spectrum of the mixture; and comparing the detected fluorescent emission spectrum with standard fluorescent emission spectra generated by reacting the dye with different known hydrogen ion activities, wherein differences between the fluorescent emission spectra compared are dependent upon the presence or levels of the hydrogen ion activity present in the mixture.

Abstract: A class of predominantly hydrophobic non-azo N-substituted 1,8-naphthalimide compounds, each bearing, at its 3-position, a nucleofuge and, at its 4-position, a heteroatomic electron-releasing group. The heteroatomic electron-releasing group is being characterized as having a heteroatom directly linked to the 4-position of the ring, and having at least one hydrogen directly attached to the heteroatom. Upon activation by an activating agent in an environment independent of the presence or absence of oxygen, these compounds generate activated species. The activated species initiate chemical changes in lipid bilayer membranes of viruses and other target cells. These changes can eradicate viruses and other target cells. The activated species can also cause structural changes in lipid and any associated proteins and polypeptides at a level beneath the surface of the membrane, leading to polymerization and crosslinking.

Abstract: The use of a class of non-azo 1,8-naphthalimide dyes for the detection and quantitation of a paramagnetic metal cation in a non-aqueous medium and some of the dyes that will complex with a paramagnetic metal cation. The concentration of the paramagnetic metal cation is determined by monitoring differences in the detected fluorescent emission spectra of the non-azo 1,8-naphthalimide dye solution when it is mixed with paramagnetic metal cations present in the non-aqueous medium. The detected fluorescent emission spectra will vary in relation to the presence or amount of the paramagnetic metal cation in the mixture.

Abstract: A class of predominantly hydrophobic non-azo N-substituted 1,8-naphthalimide compounds, each bearing, at its 3-position, a nucleofuge and, at its 4-position, a heteroatomic electron-releasing group. The heteroatomic electron-releasing group is being characterized as having a heteroatom directly linked to the 4-position of the ring, and having at least one hydrogen directly attached to the heteroatom. Upon activation by an activating agent in an environment independent of the presence or absence of oxygen, these compounds generate activated species. The activated species initiate chemical changes in lipid bilayer membranes of viruses and other target cells. These changes can eradicate viruses and other target cells. The activated species can also cause structural changes in lipid and any associated proteins and polypeptides at a level beneath the surface of the membrane, leading to polymerization and crosslinking.

Abstract: An optical disk recording system including a record medium is disclosed for providing an accurate track crossing count and an accurate track following signal. A first embodiment utilizes off-centered wobbled areas located in the headers of the record medium. The high frequency content of a first signal is combined with the low frequency content of a second signal, which is generated using the wobbled areas. In another embodiment, light-reflective discontinuities are provided in the header areas of the record medium. A qualifier and an AGC are utilized in providing a corrected track following signal. In still another embodiment, reflective discontinuities are located in the servo areas of the record medium. In such an embodiment, it is preferred that there is a fixed gain adjustment to a radial push-pull signal.

Abstract: An implantation method for the improvement of the corrosion resistance and hydrogen absorption resistance of zirconium alloys in a light water nuclear reactor environment includes the steps of sputtering a layer of hafnium ions onto a zirconium alloy and the implanting the hafnium ions with xenon doses of 3.times.10.sup.16 ions/cm.sup.2.

Abstract: Sampled servo data comprising one pit centered on a track and two pits spaced 1/4 track pitch from track center on opposite sides thereof provide for two sinusoidal tracking signals, one radially phase offset from the other by 90 degrees. A first tracking signal derived from subtracting the signals of the offset pits has a zero crossing at track center and is used by the servo system for tracking. Its derivative is used for damping. A second tracking signal derived from all three pits has maxima at track centers and is therefore 90 degrees out of phase with the first tracking signal. This second signal provides track crossing information, and when used in quadrature with the first tracking signal, provides information about the radial direction of crossing. The second signal also provides a control signal for inverting the damping signal while between tracks when the derivative of the first tracking signal would ordinarily be negative and provide for negative damping.

Abstract: A method and apparatus for controlling a tape player/recorder for retrieving and playing prerecorded selections recorded thereon at spaced locations. According to the method and apparatus, the tape is played, a number indicative of tape position is generated, the tape position numbers indicative of the start and stop points for each selection recorded on the tape are stored in a memory, and the stored start and stop numbers for each selection are subsequently recorded on the tape whereby the tape may be removed from the player/recorder and subsequently reinserted into the same or another player/recorder. When a tape is inserted into a player/recorder, the start and stop numbers are read from the tape and stored in the memory whereupon the stored numbers may be utilized for locating selections on the tape to be played.

Abstract: A remote ECG monitoring and telemetry system for use in a hospital equipped with a master antenna television cable system comprising a portable patient sensor/transmitter unit for deriving ECG information and for transmitting a first frequency signal modulated with the ECG information; a receiver/transmitter unit positioned in the patient's room for receiving the first modulated signal and for coupling directly to the master antenna television cable a second frequency signal modulated with the ECG information; a converter/amplifier unit coupled to the master antenna television cable adjacent the head end thereof for receiving the second modulated signal and for coupling back into the master antenna television cable a high power, third frequency signal modulated with the ECG information; and a receiver/demodulator unit coupled to the master antenna television cable at a central monitoring station for receiving and demodulating the third modulated signal to derive the ECG information.

Abstract: An individually addressable converter-tuner station for use in a cable television distribution system for selectively enabling the reception by conversion of at least one secure channel signal on a conventional television receiver. The converter-tuner utilizes a crystal-controlled local oscillator to provide the frequencies for converting the received secure channel carriers to a carrier receivable by the receiver. Initial filtration of the incoming secure channel carriers is accomplished in part by means of a tunable pass band filter, controlled by a variable capacitance diodes. A double balanced mixer is employed to cancel unwanted signals remaining in the filtered input to the mixer. The secure channel carriers are in the television midband range, and the local oscillator frequencies are below that range. Extensive use is made of diode switching of the crystal controlled oscillator and other components.