摘要:
In conventional one-dimensional optical storage systems, the data is arranged in a linear fashion, and the format is read out by a single spot. A two-dimensional encoded disc is different, because the data is arranged in a two-dimensional manner (bits are on a bit lattice) and the data is read out by multiple spots. It is important to know the relative intensity of the read-out spots, because the intersymbol interference is used in the signal processing of the reflected signals, and the present invention provides a way of calibrating the relative intensities by placing one or more mirror sections (150) in a non user-data area of an optical record carrier (1) and using the signals reflected therefrom to determine the relative intensities and enable the required accurate calibration of the relative intensities. In one exemplary embodiment, a mirror section (15) is located in the lead-in area (2) of the record carrier (1) in addition to a plurality of broad meta-tracks containing calibration patterns (152).
摘要:
An apparatus, method and computer program for measuring a distance using a self-mixing interference (SMI) unit that generates an SMI signal. The SMI unit comprises a laser emitting a first laser beam directed to an object and wherein the SMI signal depends on an interference of the first laser beam and a second laser beam reflected by the object. A peak width determination unit determines a peak width of the SMI signal, and a distance determination unit determines a distance between the object and the SMI unit depending on the determined peak width of the SMI signal. Since the distance is determined depending on the peak width of the SMI signal, without requiring a laser driving current modulation, advanced electronics for modulating the driving current of the laser are not needed. This reduces the technical efforts needed for determining the distance.
摘要:
The method is based on a determination of the orientation of the sensor to the surface moving with respect to the sensor and then acquiring data where the lateral velocity is small and the forward velocity is large. Then, the orientation of the sensor with respect to the direction of the forward velocity is determined and the velocity data subsequently measured are corrected using the measured orientation of the sensor with respect to the reference surface and the forward velocity direction.
摘要:
An optical storage medium (20) comprises a first data layer (21), for example a Blu-ray (BD) data layer. In addition, the optical storage medium (20) comprises a second data layer (23), for example a DVD data layer. The second data layer (23) is bonded to a substrate (25) using a third layer (27). The third layer (27) comprises an adhesive layer combined with a reactive layer. A reactive agent contained in the reactive layer acts to provide a limited lifetime to the data contained in the second layer (23). The second data layer (23) (i.e. having a limited lifetime) contains access data for controlling access to at least some of the data contained on the first data layer (21). In this way, access to a BD layer can be controlled by a separate DVD layer having a limited lifetime.
摘要:
The method is based on a determination of the orientation of the sensor to the surface moving with respect to the sensor and then acquiring data where the lateral velocity is small and the forward velocity is large. Then, the orientation of the sensor with respect to the direction of the forward velocity is determined and the velocity data subsequently measured are corrected using the measured orientation of the sensor with respect to the reference surface and the forward velocity direction.
摘要:
An arrangement for read-out of information from an optical information carrier is disclosed. The system comprises a VCSEL for improving the signal-to-noise ratio of light reflected from and modulated by an information carrier. The VCSEL has a substrate that transmits the emission from the active regions of the VCSEL. Thereby, the need for beam-splitters in the detection branch of the device is completely eliminated.
摘要:
The present invention provides a two-dimensional encoded optical storage medium (12) comprising at least one alignment pattern (14) for aligning a spot array (16) intended to read out the optical storage medium (12). Furthermore, the present invention is directed to a method and a device for reading out a two-dimensional encoded optical storage medium (12) having at least one alignment pattern (14) comprising a plurality of bit rows (R1, R2, R3, R4, R5, R6, R7, R8), wherein at least one bit row (R2, R3, R4, R6, R7, R8) of said alignment pattern (14) is empty.
摘要:
A sensor device (340) for determining a flow characteristic of an object (341) being movable in an element (342) comprises a light emitting unit (344) configured for emitting light towards the element (342) and a light detecting unit (344) configured for detecting light scattered back from the element (342). The sensor device (340) comprises an optical unit (346) configured for spatially separating a light incidence element portion (348) of the element (342) and a light detection element portion (350) of the element (342) from one another, wherein the light incidence element portion (348) is associated with the emitted light inciding on the element (342) and the light detection element portion (350) is associated with the back-scattered light scattered back from the element (342) for detection. The sensor device (340) comprises a determining unit (358) configured for determining the flow characteristic of the object (341) being movable in the element (342) based on light indicative of the emitted light and the detected back-scattered light. The sensor device (340) allows for an accurate and easy determination of the flow characteristic of the object (341).
摘要:
The present invention refers to a method of operating a self-mixing interference sensor and a corresponding self-mixing interference sensor device. In the method the laser (1) of the device is controlled to periodically emit a laser pulse followed by an emission period of laser radiation having a lower amplitude. The pulse width of the laser pulse is selected such that the pulse after reflection at the object (3) re-enters the laser (1) during the emission period of laser radiation with lower amplitude. The corresponding SMI signal has an increased signal to noise ratio.
摘要:
A sensor module (1) for measuring the distance to a target and/or the velocity of the target (50), the sensor module (1) comprising at least one laser source (100), at least one detector (200) being adapted to detect modulated laser light and at least one control element the control element (400) being adapted to vary the focus point of the laser light and/or the intensity of the laser light and/or the direction of the laser light. The control of the laser light emitted by the laser source (100) either by active optical devices as variable focus lenses or controllable attenuators or passive optical elements in combination with arrays of laser sources (100) and detectors (200) enable flexible and robust sensor modules.