Abstract: The construction roofing design includes one or more substantially static solar light PV collectors and one or more substantially static solar light directing devices. The substantially static PV collector and the substantially static solar light directing devices are facing each other at nominal angle smaller than 160° and larger than 110° . The substantially static solar light directing devices are configured to directs all or a part of the light impinging thereon towards the substantially static solar light PV collectors.

Abstract: A light collection systems with at least one light receiving element, such as a window, a photovoltaic element, a heating element, a light guiding element or combinations thereof, and at least one light reflector-deflector element. The light reflecting elements include a front light receiving surface, a rear surface, and a transparent volume, disposed between the front light receiving surface and the rear surface, the transparent layer being of a higher refractive index than of its surrounding. The transparent volume comprises an asymmetric pattern which is configured to at least partially reflect light by internal reflection and direct the light within the element, reflect some light off said front light receiving surface, reflect, deflect and guide light within the light reflector-deflector element; and direct light through the front light receiving surface towards the at least one light receiving element.

Abstract: The present invention is directed to light collection systems, the system comprising at least one light receiving element, selected from the group consisting of: a window, a photovoltaic element, a heating element, a light guiding element and combinations thereof, and at least one light reflector-deflector element, each element comprising a front light receiving surface, a rear surface, and a transparent volume, disposed between the front light receiving surface and the rear surface, the transparent layer being of a higher refractive index than of its surrounding, wherein the transparent volume comprises an asymmetric pattern which is configured to at least partially reflect light by internal reflection and direct the light within the element, reflect some light off said front light receiving surface, reflect, deflect and guide light within the light reflector-deflector element; and direct light through the front light receiving surface towards the at least one light receiving element.

Abstract: The present invention is directed to light collection systems, the system comprising at least one light receiving element, selected from the group consisting of: a window, a photovoltaic element, a heating element, a light guiding element and combinations thereof, and at least one light reflector-deflector element, each element comprising a front light receiving surface, a rear surface, and a transparent volume, disposed between the front light receiving surface and the rear surface, the transparent layer being of a higher refractive index than of its surrounding, wherein the transparent volume comprises an asymmetric pattern which is configured to at least partially reflect light by internal reflection and direct the light within the element, reflect some light off said front light receiving surface, reflect, deflect and guide light within the light reflector-deflector element; and direct light through the front light receiving surface towards the at least one light receiving element.

Abstract: A method is presented for use in determining a degree of quality of a multi-layer optical data carrier in its at least partially recorded state. Predetermined first data is provided being indicative of a qualified, at least partially recorded multi-layer optical data carrier. This data corresponds to an optical response obtainable from a specific data carrier under predetermined conditions of an optical scan of the rotating data carrier. A data carrier being qualified is scanned by at least one optical beam under said predetermined conditions of the scan, and a first control signal from the data carrier is detected and data indicative of the detected control signal is generated. The so generated data is processed to determine a relation with said predetermined data. The determined relation is used for determining a degree of quality of said scanned data carrier.

Abstract: An optical data carrier is presented. The data carrier comprises at least one recording layer, at least one non-recording layer, and at least one reflective interface. The recording layer is made of a material having a fluorescent property variable on occurrence of multi-photon absorption resulted from an optical beam, and has a thickness for recording therein data in the form of a three-dimensional pattern of spaced-apart recording regions arranged in a plurality of recording planes. The at least one non-recording layer interfaces with the recording layer on, respectively, at least one of upper and lower surfaces of the recording layer The non-recording layer has a fluorescent property different from that of the recording layer, and has a predetermined thickness selected to be equal or larger than a focal depth of an optical system producing the optical beam incidence onto the data carrier. The at least one reflective interface comprises at least one reference layer having a reflecting property.

Abstract: An optical data carrier is presented comprising first and second recordable media located in at least one first portion and at least one second portion of the data carrier, respectively. These first and second recordable media differ from each other in a storage capacity and a data recording rate.

Abstract: Cooperativity between groups within a polymeric photochromic medium provides the basis for enhanced writing effect. The cooperatively may be among photochromic groups being present in a high concentration.

Abstract: A method of driving a block of diodes having low impedance by high power pulses. A high power signal is fed through an impedance-transforming device to a block of diodes. The block of diodes includes at least one laser diode. The impedance-transforming device is one of a group of transformer or quarter wave matching section.

Abstract: An optical information carrier and method and apparatus for securing the carrier are presented. The optical information carrier comprises a recording medium for recording data therein in the form of a first pattern of spaced-apart recorded regions configured to provide a first optical response to incident light, and comprises a pattern of spaced-apart regions configured to respond to incident light by a second optical response pattern. Distribution of the spaced-apart regions forming the second optical response pattern is indicative of an individual and identifiable carrier specific signature.

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 sub-stance 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.

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 formatter for inscription of marks on to a 3D translucent optical medium to enable recording and retrieval of information from the medium, includes a clamping mechanism to hold the media, and at least one optical unit 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 moves the spot relative to the medium.

Abstract: A method, system and non-linear optical storage medium are presented for use in at least reading data in the medium. The technique utilizes a first function corresponding to an effect of data recording in the medium and a second function corresponding to an effect of reading the recorded data, where each of the first and second functions is a function of at least a power profile of applied interacting radiation in a respective one of the recording and reading events and a duration of said event. These data is utilized to select a certain operating mode defined by ranges of said power and duration parameters during the reading process corresponding to a non-degenerate relation between the first and second functions.

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 for data inscription in an acrylic polymer-based photochromic medium is provided in which the photochromic groups are bound to the polymeric matrix. The data is inscribed by irradiating small volume portion with an electromagnetic irradiation that causes a change in state of the photochromic groups from a first to a second state. Said volume portion is heated so as to cause an increase in temperature of said portion at the time of data inscription. The heating may be external or internal. Internal heating makes use of additives that dissipate heat, following their irradiation, to their immediate vicinity. Provided is also a novel acrylic polymer-based photochromic medium comprising said additives.

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 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 is presented. The information carrier comprises formatting marks disposed on the nodes of a three dimensional lattice formed by the intersection of equiangular spaced radial planes, equidistantly spaced cylindrical spiral tracks and virtual recording planes.

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.