Abstract: Some embodiments are directed to a range of method for investigating a sample such as obtaining images and/or spectral information are described. The method includes a method for deriving structural information about a sample as a continuous function of the depth below the surface of the sample, a method for evaluating a part of the structure of a sample located between two interfaces within the sample, and a contrast enhancing method and apparatus which has a quick image acquisition time.

Abstract: A system and method of using the same, wherein the system comprises: an optical surface having a diffractive image generating structure disposed thereon, the diffractive image generating structure itself comprising a layer of reflective material incorporating a plurality of grooved diffractive elements each having a periodic wave surface profile, the periodic wave surface profiles each having a groove alignment direction; a source of incident electromagnetic radiation arranged to illuminate the diffractive elements at an angle of incidence substantially normal to the plane of the surface of the diffractive elements; means for polarizing the radiation from the source, and means for polarizing radiation reflected from the diffractive elements; wherein the diffractive elements are configured such that, in use, polarization conversion of the incident radiation takes place, and wherein the diffractive elements are disposed in a two dimensional array of pixels to represent an image; and further wherein the means fo

Abstract: A system and method of using the same, wherein the system comprises: an optical surface having a diffractive image generating structure disposed thereon, the diffractive image generating structure itself comprising a layer of reflective material incorporating a plurality of grooved diffractive elements each having a periodic wave surface profile, the periodic wave surface profiles each having a groove alignment direction; a source of incident electromagnetic radiation arranged to illuminate the diffractive elements at an angle of incidence substantially normal to the plane of the surface of the diffractive elements; means for polarising the radiation from the source, and means for polarising radiation reflected from the diffractive elements; wherein the diffractive elements are configured such that, in use, polarisation conversion of the incident radiation takes place, and wherein the diffractive elements are disposed in a two dimensional array of pixels to represent an image; and further wherein the means fo

Abstract: An electromagnetic radiation decoupler for decoupling radiation in the wavelength range ?min to ?max. The decoupler has a first conductor layer in contact with a dielectric layer which comprises at least one area of absence and the thickness of the decoupler is less than ?min/4n, where n is the refractive index of the dielectric. The dielectric layer may be sandwiched between two conductor layers, one of which has the structure described above. The invention is also directed to methods of using and various articles comprising such a decoupler.

Abstract: Apparatus and methods for providing a substantially surface independent tagging system are disclosed. A resonant dielectric cavity is defined between upper and lower conducting layers, and closed at one end by a conducting base portion. Incident radiation couples into the cavity and is resonantly enhanced. An electronic device or tag paced at the edge of the cavity experiences a high electric field strength on account of this enhancement and is driven into operation.

Abstract: A radiation absorber comprising multiple layers has a conducting base layer, and at least first and second further layers, each separated by a dielectric material, the first and second layers having patches thereon of highly conducting material, and defining resonant cavities in cooperation with the dielectric material, wherein the resonant cavities formed on adjacent layers differ in frequency. Characteristics of the patch, such as size or shape may vary on each layer to provide different resonant frequencies, and/or dielectric or magnetic properties of the dielectric material, and/or separation distance of the patches may be varied. In some embodiments, complex dielectrics may have their loss factors adapted to tune a resonant frequency, or to adapt its resonant bandwidth.

Abstract: Apparatus and methods for providing a substantially surface independent tagging system are disclosed. A resonant dielectric cavity is defined between upper and lower conducting layers, and closed at one end by a conducting base portion. Incident radiation couples into the cavity and is resonantly enhanced. An electronic device or tag paced at the edge of the cavity experiences a high electric field strength on account of this enhancement and is driven into operation.

Abstract: An electromagnetic radiation decoupler for decoupling radiation in the wavelength range ?min to ?max. The decoupler has a first conductor layer in contact with a dielectric layer which comprises at least one area of absence and the thickness of the decoupler is less than ?min/4n, where n is the refractive index of the dielectric. The dielectric layer may be sandwiched between two conductor layers, one of which has the structure described above. The invention is also directed to methods of using and various articles comprising such a decoupler.

Abstract: An electromagnetic radiation decoupler for decoupling radiation in the wavelength range ?min to ?max. The decoupler has a first conductor layer in contact with a dielectric layer which comprises at least one area of absence and the thickness of the decoupler is less than ?min/4n, where n is the refractive index of the dielectric. The dielectric layer may be sandwiched between two conductor layers, one of which has the structure described above. The invention is also directed to methods of using and various articles comprising such a decoupler.

Abstract: An optical multilayer (1) comprising textured surfaces suitable for use in anti-counterfeiting and/or security applications is described.

Abstract: A radiation absorber comprising multiple layers has a conducting base layer, and at least first and second further layers, each separated by a dielectric material, the first and second layers having patches thereon of highly conducting material, and defining resonant cavities in cooperation with the dielectric material, wherein the resonant cavities formed on adjacent layers differ in frequency. Characteristics of the patch, such as size or shape may vary on each layer to provide different resonant frequencies, and/or dielectric or magnetic properties of the dielectric material, and/or separation distance of the patches may be varied. In some embodiments, complex dielectrics may have their loss factors adapted to tune a resonant frequency, or to adapt its resonant bandwidth.

Abstract: Apparatus and methods for providing a substantially surface independent tagging system are disclosed. A resonant dielectric cavity is defined between upper and lower conducting layers, and closed at one end by a conducting base portion. Incident radiation couples into the cavity and is resonantly enhanced. An electronic device or tag paced at the edge of the cavity experiences a high electric field strength on account of this enhancement and is driven into operation.

Abstract: Apparatus capable of enhancing an incident electric field to drive an electromagnetic tag (124) into operation, comprising a resonant dielectric cavity which extends out of a single plane defined between two conducting surfaces (102, 104, 106). The cavity may extend over two or more layers, and can adopt C or S shaped or spiral profiles.

Abstract: This invention relates to a security label for the detection of counterfeiting and tampering. The invention comprises a combination of an iridescent laminated or multilayered material with a lenticular layer. The iridescent layer exhibits an angular dependence in its coloration in reflection and/or transmission and the lenticular layer acts as a filter to light of a given angle of incidence.

Abstract: Apparatus and methods for providing a substantially surface independent tagging system are disclosed. A resonant dielectric cavity is defined between upper and lower conducting layers, and closed at one end by a conducting base portion. Incident radiation couples into the cavity and is resonantly enhanced. An electronic device or tag paced at the edge of the cavity experiences a high electric field strength on account of this enhancement and is driven into operation.

Abstract: A device capable of enhancing an electric field to drive an electromagnetic tag into operation is switchable between states to control operation of the tag. Enhancement is provided by a dielectric cavity structure defined between first and second conducting layers. Different states of the device may have different resonant frequencies and read ranges according to the characteristics of the enhancement. As such a container can be provided which includes a tag which switches states on opening, allowing improved tracking characteristics.

Abstract: This invention relates to the field of an electromagnetic (EM) field shielding paint compositions, in particular, those capable of providing substantially non metallic finish. The paint composition finds particular use in attenuating EM signals that may be used to carry data between communication devices, especially mobile phone and wi-fi devices. EM field shielding paints are typically available in jet-black or bright metallic finishes and usually possess limited scratch & abrasion resistance. The paint composition provides a one-pot solution to furnish a composition which has the visual appearance of a domestic type paint i.e. one with a non-metallic finish, with the ability to shield electromagnetic radiation. The composition comprises a supported metallic flake and a pigment, which have been provided in a narrowly defined range to furnish a desirable non-metallic appearance and possess electromagnetic shielding properties.

Abstract: Apparatus and methods for providing a substantially surface independent tagging system are disclosed. A resonant dielectric cavity is defined between upper and lower conducting layers, and closed at one end by a conducting base portion. Incident radiation couples into the cavity and is resonantly enhanced. An electronic device or tag paced at the edge of the cavity experiences a high electric field strength on account of this enhancement and is driven into operation.

Abstract: An electromagnetic radiation decoupler for decoupling radiation in the wavelength range ?min to ?max. The decoupler has a first conductor layer in contact with a dielectric layer which comprises at least one area of absence and the thickness of the decoupler is less than ?min/4n, where n is the refractive index of the dielectric. The dielectric layer may be sandwiched between two conductor layers, one of which has the structure described above. The invention is also directed to methods of using and various articles comprising such a decoupler.

Abstract: Apparatus and methods for providing a substantially surface independent tagging system are disclosed. A resonant dielectric cavity is defined between upper and lower conducting layers, and closed at one end by a conducting base portion. Incident radiation couples into the cavity and is resonantly enhanced. An electronic device or tag paced at the edge of the cavity experiences a high electric field strength on account of this enhancement and is driven into operation.