摘要:
A coarse position sensor is provided for an optical recording device to generate a substantially linear coarse position signal, indicative of the position of a coarse carriage along the range of its travel, and which also is substantially immune to environmental and device variations. The sensor includes a light source mounted to a drive frame at one end of the range of travel, a position sensitive device fixed to the frame at the opposite end of the range of travel and facing the light source, and a deflecting optical element mounted to the coarse carriage in the path of the light. As the coarse carriage travels along its stroke between the inner and outer diameters of the optical disk, the amount of deflection of the light beam on the position sensitive device from a reference location will change. Based upon a trigonometric equation, a coarse position signal generator receives the output of the position sensitive device and generates a substantially linear coarse position signal indicative of the position of the coarse carriage.
摘要:
A magnetooptical disk recording device has a far-field detector for detecting radial position of a laser beam with respect to tracks on the disk. The far-field detector has a reference line dividing first and second photo detectors. The reference line is centered radially with respect to center lines of the tracks. The reference line is also center lengthwise to be tangentially center with respect to a tangential point on the track. The detector is adjustable both radially and tangentially. The tangential adjustment is based upon sensing two low reflective calibration marks on the disk that indicate centering the laser beam, hence the track tangent point, on the reference line. The calibration is based upon obtaining minimum noise in the detector output signal that signifies that the laser beam is centered on the length of the detector reference line. The calibration marks are in a mirror area disposed at one radial extremity of the disk. The marks are radially elongate and disposed in a radially outward diverge with respect to each other. The marks are disposed at 45 degrees with respect to two circumferentially spaced apart radial lines of the disk.
摘要:
A particular focusing arrangement in a dual fiber collimator improves the transmission efficiency and ease of alignment of the collimator. In particular, the collimator includes two optical fibers mounted in a dual-fiber ferrule. The fiber end-faces are co-planar with the angle-polished end-face of the ferrule and displaced along the optical axis of the ferrule. The collimator unit also includes a first focusing element centered along the optical axis of the ferrule and positioned such that its back front focal point is between the two end faces of the fibers. An advantage provided by this arrangement is that by changing the fiber polish angle and polish azimuth, relative to a line connecting the fiber centers, superior coupling from one fiber to the other can be achieved, even with different working distances and at various wavelengths.
摘要:
An apparatus for providing focus and tracking error signals for controlling an application of a radiation beam to a data track of an optical storage medium is disclosed. The present invention describes a multi-element optical prism used in the optical head, which permits for a single return path, a reduced cross talk between focus and tracking error signals, and a reduced track offset.
摘要:
This invention provides an equal path length lateral shearing interferometer and its implementation in focus detection devices, particularly for optical data storage devices. The interferometer comprises a beamsplitter and two abutting roof prisms. Shifting the placement of a roof prism along an axis orthogonal to the direction of light propagation and to the peak of the roof creates a lateral shear between the two output beams. Rotation a roof prism about this axis produces a tilt between the two output beams. This creates an interference pattern with a rotational orientation which is a function of the focus of the beam impinging on the optical storage medium. A pattern sensor is provided to adjust the focus of the beam in an accurate and dynamic manner.
摘要:
A relative position error signal is calibrated in an optical storage device in which a tracking error signal (TES) varies as the light beam shifts its position through the objective lens. The calibration is performed by moving the coarse carriage to a predetermined region of the optical disk and measuring the TES. The fine actuator is adjusted until the tracking error signal equals a predetermined value. Then, the relative position error signal is read and an adjustment to the RPE gain is calculated to bring the gain to a predetermined value. The adjusted gain is used during normal disk access operations.
摘要:
The invention relates to computer-implemented methods and systems for identifying regulatory relationships between expressed regulating polypeptides and targets of the regulatory activities of such regulating polypeptides. More specifically, the invention provides a new method for identifying regulatory dependencies between biochemical species in a cell. In particular embodiments, provided are computer-implemented methods for identifying a regulatory interaction between a transcription factor and a gene target of the transcription factor, or between a transcription factor and a set of gene targets of the transcription factor. Further provided are genome-scale methods for predicting regulatory interactions between a set of transcription factors and a corresponding set of transcriptional target substrates thereof.
摘要:
The invention relates to an approach to angle tuning a thin film, interference filter device in which light is delivered to the filter from a fiber lying off-axis relative to the filter, and to a method of optically coupling such a device. The optical device comprises a lens unit having an optical axis and an adjustable effective focal length. The device also includes a first port disposed on a first side of the lens unit and on a first side of the optical axis, and an optical element disposed on the second side of the lens unit. The optical element has an optical characteristic that is dependent on the angle of incidence on the optical element. The lens unit has an adjustable focal length so light from the first port is incident on the optical element at a desired angle.
摘要:
An optoelectronic system for controlling laser drive current to produce a power level at the target independent of changes in the transmissivity of a beamsplitter positioned in the optical path between the laser source and the target. A second beamsplitter with transmissivity and reflectivity factors matched to the first beamsplitter is used to direct portions of light to two photodetectors. The two photodetectors are connected to circuits which produce a signal proportional to the power transmitted by the first beamsplitter divided by the power reflected by the second beamsplitter, that quotient multiplied by the sum of the photodetector signals to produce a final detection signal which is used as input to the servo control of laser drive current.
摘要:
The present invention provides compounds that potentiate the activity of antibiotic agents, particularly quinolones such as norflaxin. The invention further provides compositions, e.g., pharmaceutical compositions, comprising the inventive compounds. The invention also provides compositions comprising an antibiotic (e.g., a quinolone) and a compound that potentiates activity of the antibiotic. The invention further provides methods of treating a subject comprising administering any of the inventive compounds or compositions to the subject. The invention also provides screening methods to identify compounds that potentiate the activity of an antibiotic, e.g., a quinolone.