Abstract: An LED light source for LCD backlighting is described that recalibrates itself over time so that color and brightness uniformity across the backlight is maintained over the life of the backlight. The backlight contains clusters of red, green, and blue LEDs, each cluster generating a white point. In one embodiment, each color in a cluster has its own controllable driver so that the brightness of each color is a cluster is separately controllable. One or more optical sensors are arranged in the backlight, and the sensor signals are detected by processing circuitry to sense the light output of any LEDs that are energized in a single cluster. The measured white point and flux are compared to a stored target white point value and flux for that cluster. The currents to the RGB LEDs are then automatically adjusted to achieve the target level for each cluster. This process is applied to each cluster in sequence until the recalibration is complete.

Abstract: The present invention relates to a storage medium (10) comprising an information layer (11) including transparent and non-transparent areas in which the information is stored, and a magnetizable layer (12) intended to contain at least one magnetized area, which is temporarily created when a light spot is transmitted by a corresponding transparent area of the information layer. The present invention also relates to a reading device for reading information on such a storage medium (10). Said reading device comprises an optical element (23) for generating an array of light spots from an input light beam (21), a light spot being intended to temporarily create the magnetized area in the magnetizable layer (12) when passing through the corresponding transparent area of the information layer (11), and a magnetic sensor (24) comprising an array of sensor elements for detecting the at least one magnetized areas.

Abstract: The present invention provides a spectroscopic system and a transmission based imaging system for a spectroscopic system as well as a probe head for a transmission based imaging system for a spectroscopic system and a corresponding transmission based imaging method. The spectroscopic system is preferably applicable to in vivo noninvasive blood analysis. Transmission based imaging makes use of a transmitted portion of an imaging or monitoring beam that has been transmitted through biological tissue. By means of transmission based imaging, a contrast decreasing impact of scattered radiation can be effectively reduced. Additionally, by arranging the imaging light source opposite to an objective lens of the spectroscopic system, unintended propagation of spectroscopic excitation radiation into free space can be effectively prevented.

Abstract: An LED light source for LCD backlighting is described that recalibrates itself over time so that color and brightness uniformity across the backlight is maintained over the life of the backlight. The backlight contains clusters of red, green, and blue LEDs, each cluster generating a white point. In one embodiment, each color in a cluster has its own controllable driver so that the brightness of each color is a cluster is separately controllable. One or more optical sensors are arranged in the backlight, and the sensor signals are detected by processing circuitry to sense the light output of any LEDs that are energized in a single cluster. The measured white point and flux are compared to a stored target white point value and flux for that cluster. The currents to the RGB LEDs are then automatically adjusted to achieve the target level for each cluster. This process is applied to each cluster in sequence until the recalibration is complete.

Abstract: The invention relates to an information carrier, and a system for positioning such an information carrier in an apparatus. This system comprises an optical element (102) for generating a periodic array of light spots (103) intended to be applied to an information carrier (101), said information carrier (101) comprising a first periodic structure (108) intended to interfere with said periodic array of light spots (103) for generating a first Moiré pattern, and a second periodic structure (109) intended to interfere with said periodic array of light spots (103) for generating a second Moiré pattern, analysis means for deriving from said first and second Moiré patterns, the angle value (S) between said periodic array of light spots (103) and said information carrier (101), and actuation means (AC1-AC2-AC3) for adjusting the angular position of said information carrier (101) with respect to said array of light spots (103), from control signals (114) derived based on said angle value (S).

Abstract: The invention relates to an information carrier (801) comprising a data layer (802) intended to store a set of elementary data, and a holographic layer (803) for generating an array of light spots in response of a reference beam, said array of light spots being intended to be applied to said data layer (802). The invention relates to an apparatus for reading the data layer of an information carrier thanks to a holographic layer generating an array of light spots in response of a reference beam, said array of light spots being intended to be applied to said data layer. Use: optical storage.

Abstract: The invention relates to an information carrier (101) intended to be read and/or written by a periodic array of light spots, said information carrier (101) comprising a data area (105) defined by a set of elementary data areas, a first periodic structure (108) intended to interfere with said periodic array of light spots for generating a first moiré pattern, a second periodic structure (109) intended to interfere with said periodic array of light spots for generating a second moiré pattern, said second periodic structure (109) being arranged perpendicularly to said first periodic structure (108). The invention also relates to an apparatus for reading and/or writing said information carrier (101).

Abstract: An optical system comprising an optical element arranged on an optical axis in the path of a radiation beam. The optical element (2; 116; 202) comprises a birefringent material and has a non-planar face (4) through which the radiation beam passes. The optical system comprises a polarisation control system for controlling polarisation of the radiation beam such that the radiation beam has a polarisation which is non-uniform across a cross section (21; 24) taken perpendicular to the optical axis, the non-uniform polarisation having a distribution corresponding with a shape of the said non-planar face.

Abstract: A pick-up unit, an optical drive comprising such a pick-up unit, and a method of generating error-signals are described. Light reflected from an information carrier is injected into one or more VCSELs. The spatial intensity distribution of the emission from the VCSEL(s) is used for the generation of error signals in an optical pick-up unit. Alternatively, the relative timing for the switching of individual lasers of an array of VCSELs is used for the detection of error signals.

Abstract: A display device is provided in which the electro-optical effect is created through bending of bendable elements, particularly nanowires or nanotubes. Arrays of bendable elements are provided in areas of the display with the light path. This is possible in that the bendable elements are transparent in the case where they are oriented substantially perpendicular to the substrate, but will absorb light if bent at an angle. Hereto, it is of importance that polarized light is used. The bendable elements are preferably separated from the electrodes through a layer of dielectric material, and are bent under the influence of an electric or magnetic field.

Abstract: In the described method of producing a plurality of bodies bearing equal imprints of a stamp as optical structures, a stamp (13) is initially produced, by attaching particles (14) to a surface (15) of an auxiliary body (16); than, the stamp (13) is used to produce an imprint (11) on a plurality of bodies (10). Optical structures can be irradiated, producing on a screen a speckle pattern indicative of a key. It is substantially impossible to clone a given optical structure with current technological means. Optical structures represent physical One-Way Functions, easy to compute in the forward sense but unfeasible to reverse. Thus, they can be used to build an access/copy protection system of user information contained in an information carrier associated with the body 10. The reproducibility of the optical structures makes this method suitable for optical disks.

Abstract: The invention relates to a system for reading data stored on an information carrier. The system comprises a waveguide (1203) which allows displacing laterally the different components in exploiting the reflection of the light beams between a first surface (1207) and a second surface (1208) of said wave guide (1203).

Abstract: The invention relates to a system for shifting at least one light spot (903), said system comprising: —a phase-modulator (906) for generating, from an input light beam, a light beam which is phase-modulated according to a controllable phase profile, —an array of apertures (902) for generating said at least one light spot (903) from said phase-modulated light beam, a change of the phase profile implying a shift of said at least one light spot (903).

Abstract: An analysis apparatus, in particular a spectroscopic analysis apparatus, comprises an excitation system for emitting an excitation beam to excite a target region. A a monitoring system images the target region. The monitoring system being arranged to produce a contrast image in a contrast wavelength range and produce a reference image in a reference wavelength range. the contrast image and the reference image are compared to accurately identify the target region, notably a capillary blood vessel in the patient's skin.

Abstract: An LED backlight structure and technique for setting the voltages and currents for the LEDs are described. In one embodiment, red LEDs are connected in series between a first voltage regulator and a first controllable current source, green LEDs are connected in series between a second voltage regulator and a second controllable current source, and blue LEDs are connected in series between a third voltage regulator and a third controllable current source. The current sources may linear current regulators. After all the LEDs are mounted on a printed circuit board, each voltage regulator is controlled so that there is a minimum voltage drop across the current source to minimize energy dissipation by the current source. Also, after all the LEDs are mounted on the printed circuit board, the current sources are controlled to balance the three colors to achieve a target light output of the board using a light detection chamber.

Abstract: The invention relates to a system for reading data stored on an information carrier (201), said system comprising: an optical element (202) for generating an array of light spots (203) from an input light beam (204), said array of light spots (203) being intended to scan said information carrier (201), a detector (205) for detecting said data from an array of output light beams generated by said information carrier (201) in response of said array of light spots (203).

Abstract: A programmable optical component (10) for spatially controlling the intensity of a beam of radiation (b), which component comprises a programmable layer which is divided in programmable elements (4,6,8), characterized in that each programmable element comprises bendable nano-elements (8) which are switchable between a non-bend state (8) and a bend state (8?) by means of a driver field. In their bend state the nano-elements absorb radiation. The programmable element may be a switchable diffraction grating or a programmable mask.

Abstract: The present invention relates to a system for copy protection of an information carrier, said system comprising a diffractive layer for delivering a speckle pattern when illuminated by a light source, a spatial filter, which is aligned with respect to the diffractive layer, for delivering a filtered optical signal from the speckle pattern and a detector array for delivering, when illuminated by said filtered optical signal, an electrical signal. Said system further comprises means for computing a cryptographic key from the electrical signal, and means for decrypting encrypted data contained in the information carrier from the cryptographic key. It finds its application in copy protection of content carriers such as optical discs or in smart cards.

Abstract: An optical diffraction element (1) comprises a diffraction layer (4) which is divided into diffraction strips (6) alternating with intermediate strips (8). The diffraction strips comprise nano-elements (10) which are aligned in one direction and absorb radiation (b) which is linearly polarized in this direction. The diffraction element may be a linear or two-dimensional grating (1) or a Fresnel lens (160). The polarization-sensitive grating can be used in optical systems in which only radiation with a specific polarization direction should be diffracted, or in an optical record carrier to allow reading of an information structure with high spatial frequencies.

Abstract: The optical analysis system (1) is arranged to determine an amplitude of a principal component of an optical signal. The optical analysis system (1) comprises a first detector (5) for detecting the optical signal weighted by a first spectral weighting function, and a second detector (6) for detecting the optical signal weighted by a second spectral weighting function. For an improved signal-to-noise ratio, the optical analysis system (1) further comprises a dispersive element (2) for spectrally dispersing the optical signal, and a distribution element (4) for receiving the spectrally dispersed optical signal and for distributing a first part of the optical signal weighted by the first spectral weighting function to the first detector (5) and a second part of the optical signal weighted by the second spectral weighting function to the second detector (6). The spectroscopic analysis system (30) and the blood analysis system (40) each comprise an optical analysis system (1) according to the invention.