The systems and methods described herein relate to LED systems capable of generating light, such as for illumination or display purposes. The light-emitting LEDs may be controlled by a processor to alter the brightness and/or color of the generated light, e.g., by using pulse-width modulated signals. Thus, the resulting illumination may be controlled by a computer program to provide complex, predesigned patterns of light in virtually any environment.

Multicolored led lighting method and apparatus

High-brightness LEDs, combined with a processor for control, can produce a variety of pleasing effects for display and illumination. A system disclosed herein uses high-brightness, processor-controlled LEDs in combination with diffuse materials to produce color-changing effects. The systems described herein may be usefully employed to bring autonomous color-changing ability and effects to a variety of consumer products and other household items. The system may also include sensors so that the illumination of the LEDs might change in response to environmental conditions or a user input. Additionally, the system may include an interface to a network, so that the illumination of the LEDs may be controlled via the network.

Light emitting diode based products

A multicolor organic light emitting device employs vertically stacked layers of double heterostructure devices which are fabricated from organic compounds. The vertical stacked structure is formed on a glass base having a transparent coating of ITO or similar metal to provide a substrate. Deposited on the substrate is the vertical stacked arrangement of three double heterostructure devices, each fabricated from a suitable organic material. Stacking is implemented such that the double heterostructure with the longest wavelength is on the top of the stack. This constitutes the device emitting red light on the top with the device having the shortest wavelength, namely, the device emitting blue light, on the bottom of the stack. Located between the red and blue device structures is the green device structure. The devices are configured as stacked to provide a staircase profile whereby each device is separated from the other by a thin transparent conductive contact layer to enable light emanating from each of the devices to pass through the semitransparent contacts and through the lower device structures while further enabling each of the devices to receive a selective bias. The devices are substantially transparent when de-energized, making them useful for heads-up display applications.

Transparent contacts for organic devices

Because fossil fuels are becoming scarce and because of the expected climate change, our standard of living can only be maintained by a significant increase in energy efficiency. Large amounts of energy are consumed for lighting and during operation of displays. Thus, the targets are the development of economical light sources like white-light-emitting diodes and display panels with enhanced efficiency. Solar energy is converted into electricity by solar cells, and their efficiency must be improved considerably. A possible contribution might be delivered by phosphors which allow the conversion of thermal radiation into electrical energy. Although the target of energy efficiency is very important, we must not overlook that medical imaging diagnostic methods require efficient and sensitive detectors. For the solution of these central questions, inorganic solid-state materials doped with rare-earth ions are very promising and are therefore in the focus of current research activities.

Recent Developments in the Field of Inorganic Phosphors

Light emitting panel assemblies include a light emitting panel member having a uniform or variable pattern of light extracting deformities of well defined shapes in or on one or more surface areas of the light emitting panel member. The size and shape as well as the depth and angular orientation and position or location of the light extracting deformities may vary along the length and/or width of a panel surface area to obtain a desired light output distribution from the panel surface area. Also, at least some of the deformities may have planar surfaces in parallel spaced relation to a panel surface area. A focused light source may be insert molded or cast within a light transition area of the light emitting panel member to focus the light on an input surface of the light transition area with predetermined ray angles to fit a particular application. Molded supports may be provided on the panel member for supporting other parts or components in spaced relation therefrom. In another embodiment of the invention, an array of light sources may be mounted on a printed circuit board for directing light through a diffuser or lens mounted in spaced relation to the light sources for use in phototherapy treatment or the like.

Light emitting panel assemblies

A multi-color semiconductor lamp comprising a plurality of light emitting diodes disposed close to one another and respectively emitting the light of different colors and a light scattering layer covering these light emitting diodes. With this device, light emitted from any one of the plurality of light emitting diodes is visible as if it were emitted from one and the same position. The present invention therefore, makes it possible to obtain clear multi-color indication with a small-size lamp which has heretofore been difficult.

Multi-color semiconductor lamp

Luminance saturation properties of PDP phosphors

The present invention provides a plasma display device, a luminescent device, and an image display system each having an excellent moving-image quality, a long lifetime, and high performance. The plasma display device has a plasma display panel having at least a pair of substrates, a discharge gas space formed between the pair of substrates, electrodes formed on the respective opposing surfaces of the substrates, and a phosphor layer formed on the surface of one of the pair of substrates in contact with the discharge gas space and a driver circuit for driving the panel via the electrodes. In the plasma display device, the decay time ( 1/10 decay time) of light generated from each of the phosphor layers for providing red, green, and blue emission which compose the phosphor layer is not more than 8 ms. The plasma display device and the luminescent device use a blue phosphor (a divalent europium activated alkali earth silicate phosphor) having high performance under excitation caused by a vacuum UV beam and a low-speed electron beam and a composition represented by the following compositional formula: (Ae)a-c(Ae′)bSixOy:Euc.

Plasma display device, luminescent device and image and information display system using the same

A plasma display includes a display panel and a driving circuit for driving the display panel. A space for at least one color, of spaces between barrier ribs for defining discharge spaces for red, green and blue colors of the display panel is different from the spaces for other colors.

Adjustment of luminance balance of red, green and blue light emissions for plasma display by using different sized areas of phosphor layers producing corresponding colors

A white light source includes an ultraviolet-visible excitation light generation unit capable of generating visible light and ultraviolet light, and a fluorescence generation unit having a phosphor layer and being capable of generating visible light upon excitation by the ultraviolet light and uses, in the phosphor layer, a red light emitting phosphor represented by the following compositional formula: (Ca1−a−bSraEub)S:Mc, wherein a, b and c satisfy the following conditions: 0≦a<1.0, 0≦b<0.1 and 0≦c≦0.1; and M is a dopant element having absorption of excitation energy at about 350 nm to about 500 nm. The dopant element M includes rare earth elements such as Ce, Yb, Gd and Tm. By substituting part of Ca and/or Sr with Zn, the white light source can exhibit further improved performances. The white light source exhibits an increased red light component as compared with light emitted from conventional (Y1−a−bGdaCeb)3(Al1−cGac)5O12 green light phosphors and is suitably used in display apparatus.

Teruki Suzuki

Papers

Multi-color semiconductor lamp

Luminance saturation properties of PDP phosphors

Plasma display device, luminescent device and image and information display system using the same

Adjustment of luminance balance of red, green and blue light emissions for plasma display by using different sized areas of phosphor layers producing corresponding colors

White light source and display apparatus using the same