Abstract: The present invention relates to a method for checking the quality of a recording on a disk intended to be read with a first wavelength and intended to be recorded with a second wavelength, directly with the second wavelength used by the recording system. According to the invention, the method uses a modified jitter definition when a jitter value of recorded information is measured using light of the first wavelength. A special equalizer takes account of a required asymmetry.

Abstract: The present invention relates to a method for checking the quality of a recording on a disk intended to be read with a first wavelength and intended to be recorded with a second wavelength, directly with the second wavelength used by the recording system. According to the invention, the method uses a modified jitter definition when a jitter value of recorded information is measured using light of the first wavelength. A special equalizer takes account of a required asymmetry.

Abstract: A data page for optical data storage for an optical storage system, i.e. a holographic storage system, is presented. The data page includes one or more areas, which are less sensitive against a movement of the data page in a movement direction of the storage medium. A holographic storage medium comprising such data pages is presented. An apparatus for reading from and/or writing to an optical medium comprising such data pages, and to a method for reading and/or writing such data pages is presented.

Abstract: A system (SYS) for optically transmitting information, e.g., television signals, from a subcenter (HUB), e.g., a cable television head end, over a passive optical distribution network to a plurality of optical network units (ONU) includes a plurality of nodes (K1, . . . , Km) for optically transmitting further information, e.g., telephone signals, and a plurality of optical couplers (C1, C2). The further information of each node (K1, . . . , Km) is fed via a respective coupler (C1, C2) into a transmission line connected to only part of the plurality of optical network units (ONU), e.g., to only one optical network unit (ONU). Each optical network unit (ONU) is connected to a group of customer locations (END) and, for the transmission of information from this group of customer locations (END), via a further passive optical distribution network to a node (K1, . . . , Km). Each node (K1, . . . , Km,) includes means for separating the information received from the customer locations into, e.g.