Abstract: A system which transforms a liquid crystal composition having a mixture of cholesteric liquid crystal or other optically active materials and nematic liquid crystal materials from an electrically induced dynamic scattering state into an aligned nematic state by changing variables of an applied electrical field, and an imaging system wherein such a liquid crystal member is imaged in a desired image configuration by such an electrical field-induced transition system. Such systems exhibit high optical contrast and may be viewed without the aid of light polarizing devices.

Abstract: Substrates treated in the conventional manner for aligning molecules of liquid crystalline compositions are imagewise altered to form a latent alignment image which is subsequently developed with a liquid crystalline composition.

Abstract: Imaging apparatus, in which an original is subjected to reflex imaging, is provided with exposure control for selectively varying the angle of incidence upon a platen of a predetermined amount of light emanating from a light source. Exposure control is provided by an electrooptic cell comprising a layer of liquid crystalline composition between two electrodes and having a reflecting surface. The exposure system of the present invention is particularly suited for use in automatic copying machines having compact scanning apparatus.

Abstract: A light diffraction technique is set forth for monitoring the behavior of small liquid jets operating in the Rayleigh mode. This monitoring enables measurement of jet parameters, and thereby further enables on-line control of these parameters.

Abstract: Coding of a group of characters for recognition by a machine and by a human viewer is provided by coloring each character with a predetermined plurality of colors arranged in predetermined locations within a character configuration. Each character configuration in a set of characters is segregated into a plurality of sectors and each sector is coded by a predetermined one of a plurality of colors which differs from the color coding of an adjacent sector. Apparatus for forming the color-coded characters by printing and by a photoelectrophoretic process is disclosed. Apparatus for automatically recognizing characters colored according to the predetermined code comprise color detecting elements positioned in an array at a reading station for generating output electrical signals representative of the color-sector coding and circuit means coupled to the detection means for translating the color-sector signals into an electrical signal representative of a character in a set.

Abstract: Deflection and modulation of monochromatic light is achieved by providing an about 1 micron to about 6 micron thick layer of homogeneously aligned nematic liquid crystalline material having negative dielectric anisotropy between two transparent electrodes; applying a voltage between the two electrodes at a voltage level above the threshold voltage level for parallel variable diffraction mode for said nematic liquid crystalline material; directing a ribbon or beam of monochromatic light into the layer of nematic liquid crystalline material and coplanar therewith; and increasing and decreasing the applied voltage so that light diffracted by the parallel variable grating mode nematic is deflected at an angle which either exceeds or is less than a critical angle .theta..sub.c. When the deflection of diffracted light is increased in excess of critical angle .theta..sub.

Abstract: A novel projection imaging method. An imaging member is utilized comprising between two electrodes a negative photoconductor in contact with an about 1 to about 6 micron thick layer of nematic liquid crystalline material which, in the absence of an electrical field is provided in the homogeneous texture, and of negative dielectric anisotropy. A d.c. voltage above the parallel variable grating mode threshold for the nematic liquid crystalline material is applied between the two electrodes of the imaging member and the entire nematic layer goes into the parallel variable grating mode. While the voltage is applied, the negative photoconductor is exposed to imagewise configured actinic electromagnetic radiation and becomes more resistive in exposed areas. The actinic radiation causes the voltage to decrease across portions of the nematic liquid crystalline layer in contact with regions of the negative photoconductor exposed to the actinic radiation.

Abstract: A method is set forth for extending the dynamic range of imagewise exposure systems by transmitting the electromagnetic radiation image through two angularly displaced cylindrical lens arrays and then to a photosensitive surface so that the image at the photosensitive surface is imperfect.

Abstract: A method is set forth for extending the dynamic range of imagewise exposure systems by transmitting the electromagnetic radiation image through a lenticular lens array and then to a photosensitive surface so that the image at the photosensitive surface is imperfect.

Abstract: A development method and device for developing a latent image wherein an irregular surfaced vibrating bed transports toner particles from a supply area to the development area.

Abstract: A method is set forth for increasing the sensitivity and speed of a deformation imaging system. A lenticular lens array is interpositioned between the deformation imaging member and the imaging lens to thereby focus the radiation into a sharp relatively high intensity dot or line pattern.

Abstract: A method is set forth for increasing the sensitivity and speed of a deformation imaging system. Two angularly displaced lenticular lens arrays are interpositioned between the imaging member and the imaging lens to thereby focus the radiation into a sharp relatively high intensity dot pattern.

Abstract: A liquid crystalline composition comprising an optically active material and a nematic liquid crystalline material having negative dielectric anisotropy and optionally an ionizable salt, and capable of undergoing the electrohydrodynamic induced transition from the Grandjean texture to the focal-conic texture, is initially provided in the Grandjean Texture. Current is passed through the liquid crystalline composition up to its region of maximum response to electrical stimulus. A second current is then passed through the liquid crystalline composition until at least a partial optical conversion is achieved in response to electrical stimulus of the liquid crystalline composition.

Abstract: A liquid to solid addition polymerization imaging method comprises providing between two electrodes, one of which is in imagewise configuration, a polymerizable composition comprising unsaturated vinyl containing compounds; and, in the absence of chemical initiators, catalysts and electrolytes, applying an imagewise configured electrical field across the composition to polymerize the composition.

Abstract: A system for transforming an optically negative liquid crystalline composition from the focal-conic texture state to the Grandjean texture state by means of an applied electrical field which may be a D.C. electrical field or a relatively low frequency A.C. electrical field. Imaging and display systems wherein a member comprising a film of an optically negative liquid crystalline composition is imaged in a desired image configuration by the electrical field induced texture transformation system are also described.

Abstract: The optical transitions of extrinsically optically active soluble and insoluble materials become circularly dichroic when in contact with twisted nematic liquid crystalline compositions. The intensity of circular dichroism induced in the normally extrinsically optically active materials in contact with twisted nematic liquid crystalline compositions having dielectric anisotropy is selectively varied by application of an electrical field. The relative amounts of right handed and left-handed circularly polarized light in elliptically polarized light is thereby selectively variably altered, including the selective production of circularly polarized light.

Abstract: The optical transitions of extrinsically optically active soluble and insoluble materials become circularly dichroic when in contact with the twisted nematic structure of nematic liquid crystalline materials. The circularly dichroic optical properties induced in the normally extrinsically optically active materials can be utilized for information transfer applications.

Abstract: Circular dichroism within absorption bands of nematic liquid crystalline compositions of positive dielectric anisotropy in the twisted nematic structure is utilized for information transfer applications.

Abstract: An electro-optic device comprising, in turn, a first electrode, a photoconductive layer, a liquid crystalline layer, and a second electrode, and imaged with background at a voltage v.sub.o, is imaged without background by relatively slowly applying v.sub.o. Optionally, v.sub.o is relatively slowly reduced to zero to prevent background creation during removal of v.sub.o.

Abstract: The optical transitions of twisted nematic liquid crystalline compositions exhibit circular dichroism. The circular dichroism in twisted nematic liquid crystalline compositions is utilized to alter the relative amounts of left and right hand circularly polarized light in elliptically polarized light, including producing circularly polarized light.