Abstract:
An OLED includes a wide gap inert host material doped with two dopants. One of the dopants is an emissive phosphorescent material that can transport either electrons or holes. The other dopant is a charge carrying material that can transport whichever of the electrons and holes that is not transported by the phosphorescent dopant. The materials are selected so that the lowest triplet energy level of the host material and the lowest triplet energy level of the charge carrying dopant material are each at a higher energy level than the lowest triplet state energy level of the phosphorescent dopant material. The device is capable, in particular, of efficiently emitting light in the blue region of the visible spectrum.
Abstract:
The present invention is directed to organic photosensitive optoelectronic devices and methods of use for determining the position of a light source. Provided is an organic position sensitive detector (OPSD) comprising: a first electrode, which is resistive and may be either an anode or a cathode; a first contact in electrical contact with the first electrode; a second contact in electrical contact with the first electrode; a second electrode disposed near the first electrode; a donor semiconductive organic layer disposed between the first electrode and the second electrode; and an acceptor semiconductive organic layer disposed between the first electrode and the second electrode and adjacent to the donor semiconductive organic layer. A hetero-junction is located between the donor layer and the acceptor layer, and at least one of the donor layer and the acceptor layer is light absorbing. The OPSD has an optical beam spatial resolution of 20 μm and measurements are insensitive to fluctuations in incident light beam intensity and background illumination. The response of the OPSD shows high linearity, low positional error, high spatial resolution, and good beam tracking velocity. The OPSDs exhibited linearities and positional uncertainties of
Abstract:
A plurality of quantum dots each have a shell. The quantum dots are embedded in an organic matrix. At least the quantum dots and the organic matrix are photoconductive semiconductors. The shell of each quantum dot is arranged as a tunneling barrier to require a charge carrier (an electron or a hole) at a base of the tunneling barrier in the organic matrix to perform quantum mechanical tunneling to reach the respective quantum dot. A first quantum state in each quantum dot is between a lowest unoccupied molecular orbital (LUMO) and a highest occupied molecular orbital (HOMO) of the organic matrix. Wave functions of the first quantum state of the plurality of quantum dots may overlap to form an intermediate band.
Abstract:
A plurality of quantum dots comprise a first inorganic material, and each quantum dot is coated with a second inorganic material. The coated quantum dots being are in a matrix of a third inorganic material. At least the first and third materials are photoconductive semiconductors. The second material is arranged as a tunneling barrier to require a charge carrier (an electron or a hole) at a base of the tunneling barrier in the third material to perform quantum mechanical tunneling to reach the first material within a respective quantum dot. A first quantum state in each quantum dot is between a conduction band edge and a valence band edge of the third material in which the coated quantum dots are embedded. Wave functions of the first quantum state of the plurality of quantum dots may overlap to form an intermediate band.
Abstract:
An asymmetric twin waveguide (ATG) structure with an integrated amplifier and detector fabricated in a single active waveguide layer is disclosed. The structure comprises an active waveguide layer formed on a passive waveguide layer. The active and passive waveguides have different effective indices of refraction such that a first mode of light is confined primarily to the active waveguide and a second mode of light is confined primarily to the passive waveguide in the area where the waveguides overlap.
Abstract:
A photosensitive device includes a series of organic photoactive layers disposed between two electrodes. Each layer in the series is in direct contact with a next layer in the series. The series is arranged to form at least one donor-acceptor heterojunction, and includes a first organic photoactive layer comprising a first host material serving as a donor, a thin second organic photoactive layer comprising a second host material disposed between the first and a third organic photoactive layer, and the third organic photoactive layer comprising a third host material serving as an acceptor. The first, second, and third host materials are different. The thin second layer serves as an acceptor relative to the first layer or as a donor relative to the third layer.
Abstract:
A photoactive device is provided. The device includes a first electrode, a second electrode, and a photoactive region disposed between and electrically connected to the first and second electrodes. The photoactive region further includes an organic donor layer and an organic acceptor layer that form a donor-acceptor heterojunction. The mobility of holes in the organic donor region and the mobility of electrons in the organic acceptor region are different by a factor of at least 100, and more preferably a factor of at least 1000. At least one of the mobility of holes in the organic donor region and the mobility of electrons in the organic acceptor region is greater than 0.001 cm2/V-sec, and more preferably greater than 1 cm2/V-sec. The heterojunction may be of various types, including a planar heterojunction, a bulk heterojunction, a mixed heterojunction, and a hybrid planar-mixed heterojunction.
Abstract:
The present invention is directed to an organic optoelectronic device, such as an OLED device, provided with a vacuum deposited conformal composite coating for protecting the device from environmental elements such as moisture and oxygen. The present invention is also directed to a method for vacuum depositing a conformal composite coating directly onto an organic optoelectronic device, such as an OLED device, on a substrate. According to one embodiment, the invention provides a protected OLED device comprising a substrate; an active region positioned on said substrate; a first protective layer disposed over the active region; and a second protective layer disposed over the first protective layer, wherein said second protective layer comprises multiple sub-layers that further comprise an alternating series of two or more first polymeric sub-layers and two or more first high density sub-layers.
Abstract:
A photoactive fiber is provided, as well as a method of fabricating such a fiber. The fiber has a conductive core including a first electrode. An organic layer surrounds and is electrically connected to the first electrode. A transparent second electrode surrounds and is electrically connected to the organic layer. Other layers, such as blocking layers or smoothing layers, may also be incorporated into the fiber. The fiber may be woven into a cloth.