Abstract:
The present invention is directed to a 3-dimensional optical memory comprising as an active medium a compound capable of interconverting from one isomeric form to another by interaction of light. Said compound is bound to a polymer for achieving a uniform memory unit.
Abstract:
In accordance with the invention a new optical data carrier and methods for its production are provided. The optical data carrier of the invention is characterized in that different plates have different concentrations.
Abstract:
A method and apparatus for retrieving information from a three dimensional storage medium uses a three dimensional storage medium having an active medium capable of exhibiting first and second states, a data unit being represented by the ratio between the concentration of the first and second states in a given volume portion of the medium and a data sequence is represented by a sequence of data units. The active medium is irradiated with light as to concentrate light flux through a volume portion of the storage medium so as to generate in the volume portion a detectable non-linear optical response characteristic of the concentration ratio, which is detected and used for tracking.
Abstract:
A three dimensional optical information carrier (100 ) is present, the information carrier comprises formatting marks (114) disposed on the nodes (116) of a predefined three dimensional grid (168) in the body of the carrier.
Abstract:
A non-linear optical data carrier is presented. The non-linear optical data carrier is configured for recording therein information defined by a pattern of spaced-apart marks arranged in virtual data layers . The data carrier medium comprises a substance capable of being excited by a first multi-photon interaction to be switched from its first state into a second state, where the first and second states of the substance provide different response signals to a second multi-photon interaction. The substance when in the first and second states have substantially overlapping linear absorption wavelength peaks, and first and second wavelengths involved in the first and second multi-photon processes as well as the response signals wavelengths are outside the linear absorption spectrum peaks of the substance in its first and second states . The basic size of the marks and spaces is larger in the first than in the second layer. Data layers are recorded by monotically changing the focal plane depth of the recording beam.
Abstract:
A formatter (100) for inscription of marks on to a 3D translucent optical medium (101) to enable recording and retrieval of information from the medium, includes a clamping mechanism to hold the media, and at least one optical unit (103) calibrated to focus at least one diffraction limited spot within the medium at a respective depth therein. At least one light source is optimized for the inscription of marks, and at least one actuator (104) moves the spot relative to the medium.
Abstract:
A method and system are presented for use in at least reading data in a three-dimensional optical data carrier having at least one reference layer and at least one data layer. A recording/reading beam and a reference beam are focused onto the optical carrier through a common optical element creating two focal spots in different optical planes. Movement of at least said optical element is controlled such that the focal spot of said reading/recording beam tracks a data track in an addressed data layer, said controlling comprising identifying a change in an error signal from the reference layer during the reference beam tracking the reference layer, thereby adjusting a tracking target for control of the movement of the reference beam.
Abstract:
A method of formatting at least one optical information carrier is provided. The method is aimed at creating a plurality of formatting marks that are to be sequentially addressed when reading recording information in the carrier. The method comprises recording the plurality of formatting marks within the carrier volume in an interleaved order, thereby reducing delays in recording locally adjacent formatting marks thus reducing the entire carrier formatting time.
Abstract:
A method and system are presented for use in recording/reading data from an array of data units within a three-dimensional storage medium. Exciting radiation is provided in the form of first and second light beams of first and second different wavelengths, respectively. The first and second light beams are concurrently directed and focusing onto desirably distanced from each other sites in the medium and excited light of a third wavelength coming from the excited site is collected to form an excited light beam to be directed towards a detector assembly, while correcting for chromatic and spherical aberrations of the light focusing and collection. This focusing/collection is sequentially repeated for successive sites in the medium with varying depth of focus.
Abstract:
The present invention is directed to a three-dimensional memory apparatus for storing information in a volume comprising of an active medium. The active medium is capable of changing from a first to a second isomeric form as a response to radiation of a light beam having an energy substantially equal to a first threshold energy. The concentration ratio between a first and a second isomeric form in any given volume portion represents a data unit. The active medium in the memory apparatus comprises of diarylalkene derivatives, triene derivatives, polyene derivatives or a mixture thereof. The invention is further directed to means for reading the data units from the isomeric states of the active medium in different portions of said active medium where the two isomeric forms have a substantially different absorption coefficient for absorbing energy of a second threshold energy. Reading may also be carried out by measuring the scattering pattern of the two isomeric forms.