An optical member utilizing light from a point light source is enabled to visually perceive a reproduced optical image with a desired color. An optical modulation device includes an optical member having a light control part to reflect or absorb light in a predetermined wavelength and to pass through light in other than the predetermined wavelength in light in at least a visible light band, in accordance with a reproduction reference image for reproducing an original image, and a light transmissive part to pass through light in at least the visible light range including the predetermined wavelength.

A hologram display device includes a light source unit that generates light, a spatial light modulation panel that spatially modulates light received from the light source unit and generates diffracted light, and an optical unit that generates a holographic image using the diffracted light. The spatial light modulation panel includes first color filters, second color filters, and third color filters. The number of the second color filters is greater than the number of each of the first and third color filters. During a turned-on state of the spatial light modulation panel, a shortened distance in a predetermined direction between second color images displayed through the second color filters is substantially equal to a distance in the predetermined direction between first color images displayed through the first color filters and a distance in the predetermined direction between third color images displayed through the third color filters.

A method for producing a hologram (1), (1) for security elements (1a) and/or security documents (1b). One or more virtual hologram planes (10) are arranged in front of and/or behind one or more virtual models (20) and/or one or more virtual hologram planes (10) are arranged such that they intersect one or more virtual models (20). One or more virtual light sources (30) are arranged on one or more partial regions of the surface (21) of one or more of the virtual models (20). One or more virtual electromagnetic fields (40) are calculated starting from at least one of the virtual light sources (30) in one or more zones (11) of the one or more virtual hologram planes (10). In the one or more zones (11), in each case, a virtual total electromagnetic field (41) is calculated on the basis of the sum of two or more, of the virtual electromagnetic fields (40) in the respective zone (11). One or more phase images (50) are calculated from the virtual total electromagnetic fields (41) in the one or more zones (11). A height profile (60) of the hologram (1) is calculated from the one or more phase images (50) and the height profile (60) of the hologram (1) is incorporated into a substrate (2) to provide the hologram (1).

A light modulation element reproduces a light image in a specific color other than iridescence where white light is incident, without a layer that selectively transmits or reflects a specific wavelength band, and clearly reproduces a desired light image by reducing an influence of 0th-order diffracted light, and an information recording medium including the same. The light modulation element includes a factor element that reproduces a light image by modulating a phase of incident reproduction light, and has an uneven surface. A maximum diffraction efficiency Dmax in a wavelength band of between 380 nm and 780 nm in wavelength distribution of first-order diffracted light and of negative first-order diffracted light with respect to diffraction efficiency for the factor element has a local maximum value with a full width at half maximum FWHM of 200 nm or less in wavelength distribution with respect to diffraction efficiency having the maximum diffraction efficiency.

An illumination device, in particular an illumination device for a motor vehicle, comprising a light source for generating light which has components in a blue, green, and red wavelength range, and a holographic optic which the light emitted by the light source strikes, wherein the light striking the holographic optics is used at least partially for reconstructing a hologram, wherein the light emerges from the illumination device after interaction with the holographic optic, and wherein the light source is designed so that the spectral distribution of the light emitted by the light source is adapted to the spectral diffraction efficiency of the holographic optics.

According to an aspect of the present inventive concept there is provided a device for imaging of a microscopic object, the device comprising: an array of light sensitive areas, each being sensitive to detect light spanning a wavelength range of at least 400-1200 nm; at least one light source configured to generate light at a plurality of wavelengths within the wavelength range, comprising at least one wavelength in a visible part of the wavelength range and at least one wavelength in a short-wave infrared, SWIR, part of the wavelength range, and arranged to illuminate the microscopic object with the generated light such that at least part of the light is scattered by the microscopic object; wherein the device is configured to transmit the scattered light and non-scattered light, from the same light source, to the array of light sensitive areas configured to detect an interference pattern formed between the scattered light and the non-scattered light, for each wavelength.

According to an aspect of the present inventive concept there is provided a device for imaging of a microscopic object, the device comprising: an array of light sensitive areas sensitive to detect light spanning a wavelength range of at least 400-1200 nm; at least one light source comprising at least a first point of operation in which the at least one light source is configured to generate visible light, and a second point of operation in which the at least one light source is configured to generate infrared light, and being arranged to illuminate the microscopic object such that light is scattered by the microscopic object; wherein the array of light sensitive areas is configured to detect an interference pattern formed between the scattered light and non-scattered light; the device being configured to be set in a selected point of operation from the at least first and second points of operation, for detecting the interference pattern for imaging the microscopic object at a wavelength defined by the selected point of operation.

There is provided a holographic optical element including: a hologram portion including a plurality of groups of unit regions, each group of unit regions of the hologram portion being configured to produce a respective holographic image under a respective light illumination having a respective predetermined wavelength; and a colour filter portion formed on the hologram portion, the colour filter portion including a plurality of groups of unit regions, each group of unit regions of the colour filter portion being arranged on a corresponding group of the plurality of groups of unit regions of the hologram portion, whereby the plurality of groups of unit regions of the colour filter portion is spatially arranged to form a predetermined colour image. There is also provided a method of forming the holographic optical element. There is further provided an article having optical security incorporated therein.

[Problem] Propagation of parallel light inside thin glass or plastic material had not been considered to be feasible because of difficulties in producing parallel light with large aspect ratio and in light-guiding it into thin material. For this reason, there had been a problem that holograms of edge-lit reproduction type were not being brought to practical use.

[Means for Solution] A compact, simple collimator optics has been successfully made by placing a holographic diffraction grating close to a diverging light source to propagate it at the critical angle inside the medium. By making an array of this diffraction grating it has become possible to propagate parallel light of any aspect ratio inside a thin plate. Hitherto unrealized image display devices and signal devices have become possible by using the holographic diffraction gratings as described in the foregoing, or other diffraction optical elements, to introduce light from a plurality of light sources, in combination with edge-lit reproduction type image holograms.

There is provided a lighting device arranged to produce a controllable light beam for illuminating a scene. The device comprises an addressable spatial light modulator arranged to provide a selectable phase delay distribution to a beam of incident light. The device further comprises Fourier optics arranged to receive phase-modulated light from the spatial light modulator and form a light distribution. The device further comprises projection optics arranged to project the light distribution to form a pattern of illumination as said controllable light beam.