Abstract: An intermittent contact atomic force microscope includes: a cantilever configured to receive a contact resonance modulation; a sample disposed proximate to the cantilever; a contact resonance modulator in communication with the cantilever and configured to provide the contact resonance modulation to the cantilever; and a scan modulator in mechanical communication with the sample to provide a scan modulation to the sample.

Abstract: A method of reading data from a record medium (2) comprises the steps of: reading a first set of cryptographic data (3A) from a first predetermined storage location of the record medium; reading a second set of cryptographic data (3B) from a second predetermined storage location of the record medium; detecting a predefined correspondence between the first set of cryptographic data (3A) and the second set of cryptographic data (3B); outputting data only if said predefined correspondence is verified, otherwise inhibiting data output.

Abstract: A method of writing information in a storage layer (2A,2B) of a multi-layer optical storage medium (2) comprising two or more storage layers (2A,2B), especially multi-layer recordable and rewritable optical discs, especially DVD discs or BD discs. The method comprises the steps of monitoring a focus condition of an optical write beam (32b), and inhibiting the writing process in case of an axial focus displacement event. Also described is a medium access device (10), capable of writing information in a storage layer (2A,2B) of a multi-layer optical storage medium (2). The medium access device (10) comprises: light beam generating means (31) for generating a write light beam (32); focussing means (34) for focussing the write (32) in a focal spot (F) at a target storage layer (2A); write inhibit means (64) for inhibiting a writing process in case of an axial focus displacement event.

Abstract: In an optical disc drive apparatus (1) capable of writing information to a recordable optical disc (2), a control circuit (10) for controlling an optical pickup unit (5) comprises: a controllable DC controller (22) adapted to give a DC offset to an analog data signal (RF); a variable gain amplifier (23) for amplifying the DC-shifted analog data signal (RFS); an AD-converter (24) for receiving the amplified analog signal (RFA); a digital calculating block (25) for receiving the digital output Signal (RFD) 10 from the AD-converter (24) and digitally calculating at least one parameter (?, m) indicative of write operation quality; a processor (26) for receiving said at least one quality indicating parameter (?, m) and calculating a suitable power setting for the laser source of the optical pickup (5) on the basis of said at least one quality indicating parameter (?, m).

Abstract: An optical disk drive (50) comprises a radial servo system (70) for driving the position of an optical head (52) for scanning an optical disk (10) comprising at least one recording track (11; 12, 13), a focus servo system (80) for controlling the focussing of an optical beam, and a data retrieval system (90) for regenerating the digital data recorded on disk. Operative parameters of the radial servo system (70) and/or focus servo system (80) and/or data retrieval system (90) are frozen or are set to predetermined values as soon as the optical head (52) reaches a predetermined location (17) along a current track (12; 13) which is determined on the basis of a defect entry location (17) along a previous track (11; 12).

Abstract: A scanning optical device includes a number of independently moveable optical heads H1, H2. Radiation generated by a radiation source is split and made incident on the heads H1, H2 simultaneously. The separate radiation beams 35, 36 are generated by splitting a single radiation beam into two orthogonally polarized radiation beams 35, 36. The separate radiation beams are then capable of similar radial areas of the optical record carrier 2 to be read.