The invention optical device comprising a self-processing photopolymer material configured to produce a variable two- or three- dimensional diffraction pattern when said material is illuminated by a light source. The invention provides a new material science and process technology which produces a serialisable anti-counterfeit optical device, based on a self-processing photopolymer.

The invention relates to a method for recording a plurality of scatter volume holograms in a photopolymeric recording medium, the method comprising at least the following steps providing a first laser light source, providing a photopolymeric recording medium comprising a substrate and a photoactive layer, wherein the photopolymeric recording medium has an index modulation n of at least 0.04 and a thickness d of the photoactive layer of at least 25 m, irradiating the photopolymeric recording medium with the first laser light beam generated by the first laser light source with a minimum irradiation energy dosage of 3*D.sub.i, D.sub.i; being the inhibition dosage of the photoactive layer, wherein the irradiation of the photopolymeric recording medium is performed such that the light of the irradiating first laser light beam is scattered at scattering centers, the scattering centers being generated by the chemical react ion in the photoactive layer induced by the first laser light beam thus forming a plurality of scatter volume holo grams by interaction between the irradiating first laser light beam and the scattered light of the first laser light beam.

The present invention relates to a photopolymer composition comprising a photopolymerizable component and a photoinitiator system comprising a chain-substituted cyanine dye. The invention further provides a photopolymer comprising a photopolymer composition according to the invention, a holographic medium comprising a photopolymer according to the invention, the use of a holographic medium according to the invention, and a process for producing a holographic medium by using the photopolymer according to the invention and the exposure of the corresponding holographic medium with the aid of pulsed laser radiation.

An apparatus for in-line holographic imaging is disclosed. In one aspect, the apparatus includes at least a first light source and a second light source arranged for illuminating an object arranged in the apparatus with a light beam. The apparatus also includes an image sensor arranged to detect at least a first and a second interference pattern, wherein the first interference pattern is formed when the object is illuminated by the first light source and the second interference pattern is formed when the object is illuminated by the second light source. The first and second interference patterns are formed by diffracted light, being scattered by the object, and undiffracted light of the light beam. The at least first and second light sources are arranged at different angles in relation to the object, and possibly illuminate the object using different wavelengths.

The invention relates to a device for observing a sample, including: a light source able to emit an incident light wave that propagates towards a holder able to receive the sample; and an image sensor able to detect a light wave transmitted by the sample when the latter is placed between the light source and the image sensor.

The device is characterized in that the light source includes a light-emitting diode that is what is called micron-sized, a light-emission surface of which has a diameter or a largest diagonal smaller than 500 m.

The invention also relates to a method for observing a sample using such a device.

The present disclosure relates to apparatuses and methods for performing in-line lens-free digital holography of objects. At least one embodiment relates to an apparatus for performing in-line lens-free digital holography of an object. The apparatus includes a point light source adapted for emitting coherent light. The apparatus also includes an image sensing device adapted and arranged for recording interference patterns resulting from interference from light waves directly originating from the point light source and object light waves. The object light waves originate from light waves from the point light source that are scattered or reflected by the object. The image sensing device comprises a plurality of pixels. The point light source comprises a broad wavelength spectrum light source and a pinhole structure. The image sensing device comprises a respective narrow band wavelength filter positioned above each pixel that filters within a broad wavelength spectrum of the point light source.

The present invention is related to an holographic probe device for recording a gabor hologram comprising: a coherent optical fiber bundle comprising a distal end and a proximal end; a recording medium optically coupled to the proximal end of the coherent optical fiber bundle; a light source producing in use a single light beam, illuminating the distal end of the coherent optical fiber bundle and the object to be observed.

The present disclosure relates to apparatuses and methods for performing in-line lens-free digital holography of objects. At least one embodiment relates to an apparatus for performing in-line lens-free digital holography of an object. The apparatus includes a point light source adapted for emitting coherent light. The apparatus also includes an image sensing device adapted and arranged for recording interference patterns resulting from interference from light waves directly originating from the point light source and object light waves. The object light waves originate from light waves from the point light source that are scattered or reflected by the object. The image sensing device comprises a plurality of pixels. The point light source comprises a broad wavelength spectrum light source and a pinhole structure. The image sensing device comprises a respective narrow band wavelength filter positioned above each pixel that filters within a broad wavelength spectrum of the point light source.

A method for manufacturing a radial or azimuthal polarization conversion component comprises the steps of: placing a holographic recording material between two right-angle prisms, wherein the holographic recording material is divided into at least four sector-shaped areas and is partially shielded, and only one of the sector-shaped areas is exposed each time; allowing a recording light to pass through the right-angle prisms and the exposed sector-shaped area of the holographic recording material and to interfere with a reflected object light on the holographic recording material; rotating the holographic recording material to expose the other sector-shaped areas one by one to be constructed for manufacturing volume holograms with diffraction angles of 48.19 degrees, 60 degrees or about 85 degrees.