Abstract:
This invention provides an optical memory for data bits which memory consists of at least one crystal of a stable photoconductor type material such as zinc oxide (ZnO) which material may have its index of refraction change in response to the concurrent application thereto of two energy elements, an electric field of suitable potential and light energy of a first suitable frequency. One of the elements, for example, the electric field, is normally applied to the crystal and the other element, for example light, is selectively applied to spots on the crystal at which it is desired to store bits of information. The index of refraction of each such spot is changed, storing a data bit thereat. This change in index of refraction is detected by, for example, applying a light beam of a different frequency to the crystal and utilizing either an imaging system, or a polarizer and an analyzer to detect the change in index of refraction. Erasure of data may be accomplished by reversing the electric field or by irradiating the crystal with heat or light energy at a longer wavelength than that utilized for read or write. Information may be stored at various depths within the crystal by varying the electric field across the crystal or by generating the field normal to the crystallographic C axis of the crystal and utilizing electrodes at different depths of the crystal to generate the field.
Abstract:
A high impedance, low voltage, electro-optic light valve, such as, for example, a liquid crystal cell, has one terminal connected to a source of varying potential and the other terminal connected to an element adapted to be touched by a person or otherwise contacted by an impedance path to a potential which is highe or lower than the varying potential by an amount at least equal to the excitation potential of the valve. When the element is contacted, a circuit is completed through the valve, causing its optical characteristics to change. A touch (contact) responsive switch is provided by detecting the change in the optical characteristics of the valve and by generating some sort of output in response thereto. The switch may be utilized in devices such as a keyboard, a cable conductor identifier, or a touch response matrix board where an indication is required as to which of a plurality of elements has been touched or otherwise contacted. For such applications, the elements to be touched are connected through a suitable coding means to a bank of valves. The outputs from the valve detectors indicate, in a suitable code, the element touched. This invention relates to a low current electric switch which may be actuated in response to a person touching an element and to various devices, including an electronic keyboard, a cable conductor identifier, and a touch responsive matrix board, utilizing the switch.
Abstract:
An improved display device is provided utilizing a luminophor mixed with a nematic liquid crystal material. When illuminated with a selected source of radiation, the luminophor is excited to visibility, emitting a characteristic color over a wide angle. This approach may be used with liquid crystal displays operating in the dynamic scattering and field effect modes.
Abstract:
This invention relates to a plasma display device adapted for generating a display in a color other than the characteristic color of the plasma gas utilized. At least one surface of each cell cavity of the device is formed at least in part of a multiphoton down-conversion phosphor (an anti-Stokes phosphor). For one embodiment of the invention the phosphor is coated on the walls of the cavity. For another embodiment of the invention, the cavity is formed as an opening through a member of an insulating material positioned between a pair of insulating plates, the plates forming the ends of the cavity, and the phosphor is incorporated into the material of at least one of the plates at least in the region thereof forming the end of the cavity.