Abstract: The present invention relates to a variable iris using charged opaque particles, and to a method for operating such a variable iris. According to the invention, the variable iris has a first transparent substrate and a second transparent substrate, which are separated by one or more ribs to form a cell confining charged opaque particles, the first transparent substrate being provided with at least a first electrode and a second electrode both being adapted to be connected to a voltage source for acting on the charged opaque particles, and at least a third electrode adapted to be connected to the voltage source for acting on the charged opaque particles, the voltages applied to the first electrode, the second electrode, and the third electrode being controllable to have the same or opposite signs. The variable iris further has a pulse driver for applying voltage pulses to the electrodes.

Abstract: The invention relates to a portable video recorder system. This system comprises a video shooting part including an image capturing device, video compression means, a buffer memory filled by the output of the video compression means and low data rate wireless transmission equipment having a short range, and a recording part including a reception equipment and a cassette, or tape, or disk, or solid state memory recording unit. Means are provided for the simultaneous wireless transmission of data from the memory of the capturing device and the filling of this memory.

Abstract: Variable iris using charged opaque particles The present invention relates to a variable iris using charged opaque particles, and to a method for operating such a variable iris. According to the invention, the variable iris has a first transparent substrate and a second transparent substrate, which are separated by one or more ribs to form a cell confining charged opaque particles, the first transparent substrate being provided with at least a first electrode and a second electrode both being adapted to be connected to a voltage source for acting on the charged opaque particles, and at least a third electrode adapted to be connected to the voltage source for acting on the charged opaque particles, the voltages applied to the first electrode, the second electrode, and the third electrode being controllable to have the same or opposite signs. The variable iris further has a pulse driver for applying voltage pulses to the electrodes.

Abstract: The present invention is a stereoscopic display device including a transmissive image reproducing element, two light sources, an optical apparatus to direct the light emitted by one light source towards the right eye and to direct the light emitted by the other light source towards the left eye, and control means for displaying alternately an image for the right eye and an image for the left eye on the image reproducing element, and for activating the source emitting light for the right eye only when the image for the right eye is displayed and for activating the source emitting light for the left eye only when the displayed image is for the left eye. The optical apparatus is a mirror apparatus providing either a converging beam or a parallel beam.

Abstract: The invention relates to a portable video recorder system.

Abstract: The invention concerns a three dimensional (3D) display apparatus of the integral photography type comprising a passive array (32) of points and an array (30) representing the image to be displayed, this second array comprising a set of subarrays. Each subarray is associated with a corresponding point of the passive array, and each point of each subarray contains an information about a point of the 3D image to be displayed. A light ray from a point of a subarray to the associated point of the passive array virtually converges to the corresponding point of the 3D image to be displayed.

Abstract: A plasma display panel having a back substrate, a first set of parallel electrodes associated to the back substrate, a front transparent substrate, a second set of electrodes associated to the front substrate, the electrodes of the second set having a direction which is transverse with respect to the direction of the electrodes of the first set, and partition walls which are situated between the back and the front substrates, and extend in the direction of the second set of electrodes. This display is characterized in that: each electrode of the second set faces the edge of a corresponding partition wall, and each electrode of the second set comprises, for each cell, a transparent protrusion extending towards the side of the partition wall corresponding to this cell. The display may be of the matrix type or of the coplanar type.

Abstract: The invention concerns a three dimensional (3D) display apparatus comprising a passive array (16) of points (a, b, c) and an array (14) representing the image to be displayed, this second array comprising a set of subarrays (A′, B′, C′) Each subarray is associated with a corresponding point of the passive array, and each point of each subarray contains an information about a point of the 3D image to display. A light ray from a point (A′5) of a subarray to the associated point (a) of the passive array virtually converges to the corresponding point (P1) of the 3D image.

Abstract: Known LCD projectors, used for example in TV sets, can only be manually adjusted for the compensation of the changing color spectrum of the lamp due to its aging process. An LCD projector according to the invention further comprises an image sensor to measure the light intensity of the lamp. In a color adjusting circuit the image color is compensated as a function of the measured signal by controlling the LCD valve.

Abstract: An arrangement which can produce a stereoscopic image simply and cheaply. An optical unit views an object and a stereoscopic image is provided onto a recording device or a display device by differentially polarizing the beams.

Abstract: A plasma display panel is formed by a front plate and a back plate spaced apart from one another so that a discharge space is formed to accommodate a plurality of light generating display cells. To increase the luminance on the front side of the plasma display panel a mirror surface or a plurality of mirror surfaces is provided at the back side of the plasma display panel and/or at side-walls of cells of the plasma display panel.

Abstract: Stereoscopic effects can be created by binocular parallax. Known stereoscopic display systems show pseudoscopic effects in outer areas of the image viewing position and the viewing position is fixed. To avoid such pseudoscopic effects and/or to change the viewing position stereoscopic displays using parallax barriers with variable pitch length, moving barriers parallel to the display plane, and a polarizing device forming polarized light together with polarizing prisms are provided.

Abstract: A device for reproducing a stereoscopic image viewable within an increased observation area, the device including an image display device which displays a plurality of images of an object pixel by pixel from various perspectives, a polarization arrangement for producing a first polarized image associated with a right eye and a second polarized image associated with a left eye of an observer, a lens network spaced directly after the polarization arrangement which directs beams associated with each of the left and right polarized images to the respective left and right eye for representing the object pixel by pixel for observing the stereoscopic image, wherein the lens network and polarization arrangement are arranged such that the stereoscopic image can be perceived in a first region of the observation area without polarized spectacles, and in a second region outside the first region of the observation area, by means of polarized spectacles over the left and right eyes.

Abstract: A private stereoscopic display is provided which has only one stereoscopic viewing position and does not show pseudoscopic images in areas outside the viewing position. On top of the display there is provided a first lenticular lens sheet followed by a prism array sheet and in general by a second lenticular lens sheet. Lens stripes are provided for rows of pixels, consisting normally of two rows of pixels for the left and right image. Two separate side lobes of the light rays generated by the first lenticular lens sheet. The individual lens pixel array arrangement are separated by barriers from each other. Because of those barriers only the main lobe of the light emating from the display is maintained, so that because of the prism array sheet and the second lenticular lens sheet main lobes for the left image are focused in a left image viewing point, whereas main lobes for the right image are focused in a right image viewing point.

Abstract: A multi beam track system and method is used for the retrieving of information stored in optical memories like optical disks. The information carrying beams reflected on the surface of such a optical disk results in spots on the surface of a detector array. Because these beams are very close to each other, the resulting spots tend to overlap so that cross talk conditions between neighboring channels occur. As result the S/N ratio becomes worse. According to the present invention a plurality of laser beams arranged in a row is used, where the laser beams are linear polarized and the polarization of neighboring beams differ by 90.o slashed., i.e. neighboring laser beams have perpendicular linear polarization. After reflection on the surface of the optical disk the row of reflected laser beams is separated into two rows by an separating means which is polarization dependent so that beams are separated in space according to the polarization.

Abstract: In laser feedback systems of an optical memory the most suitable feedback gain value depends on the type of optical disks used. According to the invention a system and a method is provided which finds by way of an iteration a suitable maximum feedback gain value so that the feedback system does not oscillate. The method consists in starting with a low gain value for driving a laser diode, increasing the gain value by small amounts until an oscillation detecting unit detects that the laser feedback system is oscillating. Then the gain value is reset to the previous value or a little bit more. Then the laser feedback system is again in a non-oscillating area with a suitable maximum gain value. This iteration is performed by a system consisting mainly of a laser diode, a photodiode for detecting the reflected light, and an oscillation detecting unit which controls a gain controller. This gain controller sets the gain on a multiplier which drives the laser driver for the laser diode.

Abstract: A magneto optical disc system includes a disc having permanently recorded tracks overlain with magneto optical recording material. Data is recorded in the magneto optical material in tracks superimposed over the permanently recorded tracks, using the read-only data to define magneto optical tracks. The magneto optically recorded data is correlated with the prerecorded data for defining the location of data stored in the magneto-optic tracks.

Abstract: A system for reducing noise in a data recording/play-back device includes an optical system for scanning a recording medium and providing first and second polarization signals. The polarization signals are added to provide an added signal. The added signal is differentiated to provide a noise reduction signal. The polarization signals are substracted to provide a difference signal. The differentiated signal is substracted from the difference signal to provide a data signal having a substantially reduced noise level.