A wristwatch dial illumination system with a light guide beneath a light transmissive dial receiving light from an LED mounted on a PC board below the light guide. A pattern of white reflective dots on the bottom surface,of the light guide selectively ejects internally reflected light toward the dial and an absorption pattern of light absorbing material selectively absorbs ejected light, including the bright spot from the LED.
A display apparatus is provided with a display member which is printed in gradations of color from a first color to a second color from one side of the member to other side, and an electro-optical display device having plural dot display sections disposed on the display member. The plural dot display sections are selectively driven, to display characters, images, etc. in gradations of color. The display apparatus which is simple in structure and low in manufacturing cost advantages to improve image and/or character discrimination and is used for an adornment purpose.
An illumination device for a magnetically sensitive instrument comprising a magnetically sensitive instrument, preferably a magnetic compass needle, and an electroluminescent device comprising an electroluminescent panel positioned behind and facing the magnetically sensitive instrument such that when the electroluminescent panel is activated, the magnetically sensitive instrument is illuminates by the electroluminescent light. The device is powered by a battery and further comprises a driver circuit to control the electroluminescent panel and switching means to engage and disengage the battery for selective operation of the light source.
The backlighting device (1) enables an information display element of a portable object such as a wristwatch to be illuminated from the back. This device comprises a light guide plate (7) having a front face and a rear face, a light reflector (6) located on the rear face of the light guide plate, a light diffuser film (9) and a rectifier film (11) located on the front face of the light guide plate and a source of visible light (2). This light source, such as a light emitting diode (2), feeds light beams to the edge of the light guide plate, which spread in the light guide plate between its two faces. A layer, such as a diffuser film, has a zone (10') with opacity decreasing from a limit (25) located close to the boundary area of the light guide plate, which receives the light beams of the light source, in order to attenuate the intensity of the light crossing said zone. This zone with decreasing opacity is, for example, a shading white or silver dye disposed on the diffuser film, or a semi-transparent metal covering of variable thickness, or a metal covering pierced by a plurality of small holes of varying diameter and spacing, or a metal covering formed from a plurality of metal dots of varying diameter and spacing so that light beams are partially reflected and returned into the light guide plate to reduce the losses of useful photons.
This invention provides a novel application of a semiconductor light emitting element or light emitting chip preferably disposed on the underside surface of a clear or translucent substrate. In addition connecting wires leading from said element to the perimeter of the substrate connecting to contact pads leading to a circuit board. The conductors are deposited on the substrate using thin film technology. Preferably the light emitting element is packaged in a flip chip having connecting bumps only on one side.
An instrument gauge display for a vehicle dash includes a transparent dial having an upper surface partially covered by black paint and a lower surface covered with white paint. Uncovered areas on the upper surface define a plurality of graphical images that indicate a vehicle operating condition. A light guide, supported within a light housing, is positioned underneath the dial. The light housing and at least one light source is mounted to a printed circuit board, which is supported underneath the light guide by a vehicle structure. The light guide includes a plurality of scattering elements that are positioned generally underneath each of the graphical areas on the dial. The light source cooperates with the light guide and scattering elements to improve the light efficiency.