Abstract: Pointing and positioning system of light beams and images including a plurality of cycloidal diffractive waveplates, each waveplate capable of deviating a generally broadband light beam over a predetermined angle. The lateral translation and deviation angles of the light beams are controlled by controlling the relative distance, rotational position, and the diffraction efficiency of at least one in the plurality of waveplates.

Abstract: The objective of the present invention is providing a method for fabricating high quality diffractive waveplates and their arrays that exhibit high diffraction efficiency over large area, the method being capable of inexpensive large volume production. The method uses a polarization converter for converting the polarization of generally non-monochromatic and partially coherent input light beam into a pattern of periodic spatial modulation at the output of said polarization converter. A substrate carrying a photoalignment layer is exposed to said polarization modulation pattern and is coated subsequently with a liquid crystalline material. The high quality diffractive waveplates of the present invention are obtained when the exposure time of said photoalignment layer exceeds by generally an order of magnitude the time period that would be sufficient for producing homogeneous orientation of liquid crystalline materials brought in contact with said photoalignment layer.

Abstract: An apparatus and method for fabricating high quality one- or two-dimensional diffractive waveplates and arrays that exhibit high diffraction efficiency and capable of inexpensive large volume production. A generally non-holographic and aperiodic polarization converter for converting the polarization of a coherent input light beam of a visible wavelength into a pattern of continuous spatial modulation at the output of the polarization converter. A photoresponsive material characterized by an anisotropy axis according to polarization of the light beam is exposed to a polarization modulation pattern and coated subsequently with an anisotropic material overlayer with ability of producing an optical axis orientation according to and under the influence of the anisotropy axis of the photoresponsive material layer.

Abstract: Optical systems for controlling with propagation of light beams in lateral and angular space, and through optical apertures. The light beams include laser beams as well as beams with wide spectrum of wavelengths and large divergence angles. The optical systems are based on combination of diffractive waveplates with diffractive properties that can be controlled with the aid of external stimuli such as electrical fields, temperature, optical beams and mechanical means.

Abstract: A cycloidal diffractive waveplate (50) comprising first and second substrate layers (52, 54), a liquid crystal layer (60C, 60H) provided between the first and second substrate layers, and transparent positive electrodes (56) and transparent negative electrodes (58) provided on the first substrate layer. The liquid crystal layer has a diffractive state (60C) in which the optical axes of the liquid crystal molecules are periodically rotated across a plane of the waveplate and a non-diffractive state (60H) in which the optical axes of the liquid crystal molecules are all orientated in the same direction in the plane of the waveplate. The electrodes (56, 58) are arranged in an alternating series, such that when an electric voltage is applied to the electrodes an electric field is produced in the plane of the waveplate and the liquid crystal layer is switched from the diffractive state to the non-diffractive state. A method of manufacturing the cycloidal diffractive waveplate is also provided.

Abstract: Pointing and positioning system of light beams and images including a plurality of cycloidal diffractive waveplates, each waveplate capable of deviating a generally broadband light beam over a predetermined angle. The lateral translation and deviation angles of the light beams are controlled by controlling the relative distance, rotational position, and the diffraction efficiency of at least one in the plurality of waveplates.

Abstract: A method of fabricating a liquid crystal polymer film includes providing a support substrate having a surface having a shape arranged to define a form of a liquid crystal polymer film to be fabricated; applying a layer of a photoaligning material over the surface of the support substrate, the photoaligning material having an absorption band; exposing the layer of photoaligning material to a light having a linear polarization and the light comprising a wavelength within the absorption band to convert the layer of photoaligning material into a layer of photoaligned material; applying a layer of a polymerizable liquid crystal over the layer of photoaligned material; performing photopolymerization of the layer of polymerizable liquid crystal to form a liquid crystal polymer film; applying a solvent to the layer of photoaligned material, the solvent formulated to dissolve the photoaligned material to thereby release the liquid crystal polymer film from the support substrate; and removing the liquid crystal polymer

Abstract: Pointing and positioning system of light beams and images including a plurality of cycloidal diffractive waveplates, each waveplate capable of deviating a generally broadband light beam over a predetermined angle. The lateral translation and deviation angles of the light beams are controlled by controlling the relative distance, rotational position, and the diffractive efficiency of a least one in the plurality of waveplates.

Abstract: The objective of the present invention is providing optical systems for controlling with propagation of light beams in lateral and angular space, and through optical apertures. Said light beams include laser beams as well as beams with wide spectrum of wavelengths and large divergence angles. Said optical systems are based on combination of diffractive waveplates with diffractive properties that can be controlled with the aid of external stimuli such as electrical fields, temperature, optical beams and mechanical means.

Abstract: A method of fabricating a liquid crystal polymer film includes providing a support substrate having a surface having a shape arranged to define a form of a liquid crystal polymer film to be fabricated; applying a layer of a photoaligning material over the surface of the support substrate, the photoaligning material having an absorption band; exposing the layer of photoaligning material to a light having a linear polarization and the light comprising a wavelength within the absorption band to convert the layer of photoaligning material into a layer of photoaligned material; applying a layer of a polymerizable liquid crystal over the layer of photoaligned material; performing photopolymerization of the layer of polymerizable liquid crystal to form a liquid crystal polymer film; applying a solvent to the layer of photoaligned material, the solvent formulated to dissolve the photoaligned material to thereby release the liquid crystal polymer film from the support substrate; and removing the liquid crystal polymer

Abstract: The objective of the present invention is providing a method for fabricating high quality diffractive waveplates and their arrays that exhibit high diffraction efficiency over large area, the method being capable of inexpensive large volume production. The method uses a polarization converter for converting the polarization of generally non-monochromatic and partially coherent input light beam into a pattern of periodic spatial modulation at the output of said polarization converter. A substrate carrying a photoalignment layer is exposed to said polarization modulation pattern and is coated subsequently with a liquid crystalline material. The high quality diffractive waveplates of the present invention are obtained when the exposure time of said photoalignment layer exceeds by generally an order of magnitude the time period that would be sufficient for producing homogeneous orientation of liquid crystalline materials brought in contact with said photoalignment layer.

Abstract: Pointing and positioning system of light beams and images comprising a plurality of cycloidal diffractive waveplates, each waveplate capable of deviating a generally broadband light beam over a predetermined angle. The lateral translation and deviation angles of the light beams are controlled by controlling the relative distance, rotational position, and the diffraction efficiency of at least one in the plurality of said waveplates.

Abstract: The objective of the present invention is providing optical systems for controlling with propagation of light beams in lateral and angular space, and through optical apertures. Said light beams include laser beams as well as beams with wide spectrum of wavelengths and large divergence angles. Said optical systems are based on combination of diffractive waveplates with diffractive properties that can be controlled with the aid of external stimuli such as electrical fields, temperature, optical beams and mechanical means.

Abstract: A method of fabricating a liquid crystal polymer film includes providing a support substrate having a surface having a shape arranged to define a form of a liquid crystal polymer film to be fabricated; applying a layer of a photoaligning material over the surface of the support substrate, the photoaligning material having an absorption band; exposing the layer of photoaligning material to a light having a linear polarization and the light comprising a wavelength within the absorption band to convert the layer of photoaligning material into a layer of photoaligned material; applying a layer of a polymerizable liquid crystal over the layer of photoaligned material; performing photopolymerization of the layer of polymerizable liquid crystal to form a liquid crystal polymer film; applying a solvent to the layer of photoaligned material, the solvent formulated to dissolve the photoaligned material to thereby release the liquid crystal polymer film from the support substrate; and removing the liquid crystal polymer

Abstract: A cycloidal diffractive waveplate (50) comprising first and second substrate layers (52, 54), a liquid crystal layer (60C, 60H) provided between the first and second substrate layers, and transparent positive electrodes (56) and transparent negative electrodes (58) provided on the first substrate layer. The liquid crystal layer has a diffractive state (60C) in which the optical axes of the liquid crystal molecules are periodically rotated across a plane of the waveplate and a non-diffractive state (60H) in which the optical axes of the liquid crystal molecules are all orientated in the same direction in the plane of the waveplate. The electrodes (56, 58) are arranged in an alternating series, such that when an electric voltage is applied to the electrodes an electric field is produced in the plane of the waveplate and the liquid crystal layer is switched from the diffractive state to the non-diffractive state. A method of manufacturing the cycloidal diffractive waveplate is also provided.

Abstract: An apparatus and method is presented for fabricating high quality one- or two dimensional diffractive waveplates and their arrays that exhibit high diffraction efficiency over large area and being capable of inexpensive large volume production. Employed is a generally non-holographic and aperiodic polarization converter for converting the polarization of a coherent input light beam that may be of a visible wavelength into a pattern of continuous spatial modulation at the output of said polarization converter. A photoresponsive material characterized by an anisotropy axis that may be formed or aligned according to polarization of said light beam is exposed to said polarization modulation pattern and may be coated subsequently with an anisotropic material overlayer.

Abstract: The objective of the present invention is providing a method for fabricating high quality diffractive waveplates and their arrays that exhibit high diffraction efficiency over large area, the method being capable of inexpensive large volume production. The method uses a polarization converter for converting the polarization of generally non-monochromatic and partially coherent input light beam into a pattern of periodic spatial modulation at the output of said polarization converter. A substrate carrying a photoalignment layer is exposed to said polarization modulation pattern and is coated subsequently with a liquid crystalline material. The high quality diffractive waveplates of the present invention are obtained when the exposure time of said photoalignment layer exceeds by generally an order of magnitude the time period that would be sufficient for producing homogeneous orientation of liquid crystalline materials brought in contact with said photoalignment layer.

Abstract: The objective of the present invention is providing a method for fabricating high quality diffractive waveplates and their arrays that exhibit high diffraction efficiency over large area, the method being capable of inexpensive large volume production. The method uses a polarization converter for converting the polarization of generally non-monochromatic and partially coherent input light beam into a pattern of periodic spatial modulation at the output of said polarization converter. A substrate carrying a photoalignment layer is exposed to said polarization modulation pattern and is coated subsequently with a liquid crystalline material. The high quality diffractive waveplates of the present invention are obtained when the exposure time of said photoalignment layer exceeds by generally an order of magnitude the time period that would be sufficient for producing homogeneous orientation of liquid crystalline materials brought in contact with said photoalignment layer.