Abstract:
The generation of terahertz electromagnetic radiation, using a laser which is incident upon an electrically biased photoconductor and an antenna. The device has a layered structure comprising a semiconductor substrate below a wetting layer (55) epitaxially grown on the substrate, barrier layers (57) are positioned above and below a quantum dot layer (59). A contact layer (60) is provided with a contact (61) which couples the quantum dot structure to a voltage source (63). The reduction of the carrier lifetime in a conducting state, allied to its high carrier mobility that is possibly comparable to that of bulk GaAs can provide fast photoconductive devices and produce sources of terahertz radiation.
Abstract:
The present invention relates to a liquid crystal display panel having a built-in touch screen, and particularly, to a liquid crystal display panel having a built-in touch screen in which photoconductive cells (CDS cells) are arranged on an upper surface of a black matrix to identify the location at which a touch on the liquid crystal display panel occurs. Consequently, a sensor for sensing the location at which a touch on the liquid crystal display panel occurs is prevented from being contaminated or from erroneously operating when broken, which might otherwise occur when the sensor is outwardly exposed, thereby improving the reliability of products, and simplifying manufacturing processes which thus improves productivity.
Abstract:
Die vorliegende Erfindung betrifft eine Vorrichtung zur Erzeugung und Erfassung kohärenter elektromagnetischer Strahlung (8) im THz-Frequenzbereich mit einem optisch parametrischen Oszillator (2) zur Erzeugung elektromagnetischer Strahlung im THz-Frequenzbereich (8). Um eine Vorrichtung zur Erzeugung und Erfassung elektromagnetischer Strahlung im THz-Frequenzbereich bereitzustellen, wird erfindungsgemäß vorgeschlagen, daß sie einen kohärenten phasenempfindlichen Detektor (3, 21) zur Erfassung von Intensität und Phase der von dem optisch parametrischen Oszillator (2) erzeugten elektromagnetische Strahlung aufweist.
Abstract:
For obtaining a light modulator (1) for modulating light which can be addressed without the need for an active or passive matrix and in which it is relatively easy to realize a light transmissive mode of operation, the light modulator (1) has a light modulating element (2) having a light outcoupling surface (91) for coupling out the modulated light, an electrophoretic medium (5) comprising charged particles (6), an optical state depending on a position of the particles (6), an element (17) being able to be addressed by an output of an energy source for allowing a movement of the particles (6) to their position for modulating the light as a consequence of an electric field applied to the light modulating element (2). In one aspect, the applied electric field and the medium (5) are arranged for the movement to have a component in a plane parallel to the light outcoupling surface (91). In another aspect, a colour filter is used to reduce the sensitivity of the element to ambient light.
Abstract:
An optically addressable display comprises a pixels (Pi) which has a pixel volume (PVi) filled with a material (BMi) which comprises moveable charged particles (PAi). The pixel volume (PVi) comprises: a reservoir volume (RVi) in which particles are invisible to a viewer, and a display volume (DVi) in which particles are visible to the viewer. The pixel (Pi) comprises a second electrode (DEi; REi) and a third electrode (REi; DEi), both being associated with the pixel volume (PVi) to generate an in-plane electric field (EFi) in the pixel volume (PVi) to move the particles (PAi) between the reservoir volume (RVi) and the display volume (DVi). The pixel (Pi) further comprises a first electrode (BEi) which has a first surface area (SA1i) smaller than a pixel area (PIAi), and a photoconductor (PCi) arranged between the first electrode (BEi) and the third electrode (REi; DEi). The optically addressable display further comprises: a driver (DR) which supplies a first voltage (VIi) to the first electrode (BEi), and a second voltage (V2i) to the second electrode (DEi; REi). The third electrode (REi; DEi) is floating. A light source (LS) selectively illuminates the photoconductor (PCi).
Abstract:
A projection display screen that can electrically alter the reflectivity of a region of the projection display screen in response to the intensity of incident projected light that is applied at the region, wherein the projection display screen level of incident projeted light is above a prescribed intensity threshold value for ambient light. Thus, an improved contrast can be achieved. Electronic ink, bi-colored particles, polarizing layers or electrostatically de-wettable material can be used.
Abstract:
A projection display screen that can electrically alter the reflectivity of a region of the projection display screen in response to the intensity of incident projected light that is applied at the region.
Abstract:
A display for displaying and storing images comprises an optically addressable electrophoretic display (PD) with a stack of a photoconductive layer (PCF) and an electrophoretic layer (EF) being sandwiched between electrodes (E1, E2). An optical addressing means (AD) supplies addressing light (AL) to the photoconductive layer (PCF). A controller (CO) controls a driver (DR1) to supply a drive voltage (DV) between the electrodes (E1, E2) with a value enabling a change of the optical state of the electrophoretic layer (EF) in response to the addressing light (AL) impinging on the photoconductive layer (PCF). Finally, the power consumption of the optical addressing means (AD) is minimized.
Abstract:
A system for imaging electronic paper is disclosed. The system places a photoconductive layer into the electronic paper. For example, a layer of selenium, cadmium sulfide, photoconductive silicon, or any organic photoconductor (OPC) may be used in the photoconductive layer. The entire electronic paper is exposed to the same electrical potential (not selectively in a grid), but the electrostatic display cells are insulated from the electrical potential by the photoconductive layer. The photoconductive layer is then selectively illuminated by a focused light source (e.g., a scanning laser beam), thereby exposing selected electrostatic display cells to the electrical potential and writing an image to the electronic paper. In this manner, electronic paper may be imaged using existing high-resolution laser printing mechanisms.