Dai Nippon Printing Co., Ltd.

Olympus Corporation

Nikon Corporation

Konica Minolta Opto, Inc.

Dia Nippon Printing Co., Ltd.

Masachika Watanabe

Kenji Ueda

Tsuyoshi Yamauchi

Masanori Umeya

Koji Eto

Tomoko Kumasawa

Hiroyuki Ohtaki

Mitsuru Kitamura

Daijiro Kodama

Emi Takabayashi

Miwa Ishimoto

Makio Kurashige

Tetsuhide Takeyama

Takahiro Amanai

Tsuyoshi Hotta

Yasuyuki Oyagi

Minoru Azakami

Shingo Nishikawa

Toshikazu Segawa

Yuko Kuwabara

Toru Iwane

Norihisa Moriya

Tsuyoshi Kashiwagi

Hiroyuki Otaki

Nobuhiko Ichikawa

Akiko Kitamura

Daijiro Kodoma

Kenji Michiue

Tomonobu Moriya

Masashi Iwasaki

Toshihiro Kubota

A process by which a multi-image type hologram, wherein one 3D image changes over to another depending on a viewing direction, can be fabricated in a simple construction, and a multi-image type hologram fabricated by that process. According to the process for the fabrication of a multi-image type hologram wherein one image changes over to another depending on a viewing direction, the area of a hologram recording material is divided into a plurality of sub-areas. Objects to be displayed on different images are holographically recorded in the respective sub-areas, using reference light having the same angle of incidence, images recorded in the respective sub-areas are simultaneously reconstructed from the recorded first-stage hologram, so that a second-stage hologram recording material is located near the reconstructed object images for recording them as a reflection or transmission type volume hologram.

Fabrication process of multi-image type hologram, and multi-image type hologram fabricated by that process

The invention provides a process capable of fabricating a cholesteric liquid crystal medium having a volume hologram with efficiency yet without recourse to complicated steps such as an alignment step. This is achievable as follows. A volume hologram layer is formed on a substrate, and a cholesteric liquid crystal layer is then formed on another substrate. The volume hologram layer and the cholesteric liquid crystal layer are laminated together via a bonding layer. Further, a bonding for lamination onto an application member is formed on either the volume hologram layer side or the cholesteric liquid crystal layer side to obtain a cholesteric liquid crystal medium having a volume hologram.

Fabrication process for cholesteric liquid crystal media having a volume hologram

A main object of the present invention is to provide a hologram observation sheet with a transmission type hologram formed integrally with other members, to be attached with various members for the use as for example an advertising medium or a decoration member. To achieve the object, the invention provides a hologram sheet comprising: a transparent substrate, a hologram layer formed on the transparent substrate and having a transmission type Fourier transform hologram region having the function of transforming a light beam incident from a point light source to a desired optical image, and a pressure-sensitive adhesive layer.

Hologram sheet and hologram observation sheet using same, and blinding device

A volume hologram layer () is formed on a substrate (), and a cholesteric liquid crystal layer () is then formed on the hologram layer (). After the substrate () is peeled off the volume hologram layer (), an adhesive layer () is formed on the surface of the volume hologram layer () with the substrate () peeled off, and another substrate () is then formed on the adhesive layer (). Finally, a label form of cholesteric liquid crystal medium having a volume hologram is shaped out of the resulting multilayer structure; it is thus possible to fabricate cholesteric liquid crystal media having a volume hologram with efficiency yet without recourse to any complicated steps such as an alignment step.

The invention provides a hologram fabrication process, characterized by comprising steps of fabricating a computer-generated hologram (CGH) having amplitude information and phase information recorded by computer operation on a given recording surface, irradiating the computer-generated hologram (CGH) with the first reconstructing illumination light () to generate the first diffracted light () from the computer-generated hologram (CGH) thereby reconstructing a first reconstruction image (O'), simultaneously entering the first diffracted light () and the first reference light () in a first-stage hologram recording material () faced away from the first reconstructed image to record a first-stage hologram () in it, irradiating the recorded first-stage hologram () with the second reconstructing illumination light () to generate the second diffracted light () from the first-stage hologram () thereby reconstructing the second reconstruction image (O&#x2033;), and simultaneously entering the second diffracted light () and the second reference light () in a second-stage hologram recording material () located near the second reconstructed image (O&#x2033;) to record the second-stage hologram () in it as a reflection or transmission type volume hologram.

Hologram fabrication process, and hologram fabricated by that process

A volume hologram recording material is located on the side of a reflection type volume hologram master onto which copying illumination light is incident, and the copying illumination light incident onto the recording material and light diffracted through the master interfere together in the volume hologram recording material thereby copying the reflection type volume hologram master. In this case, a reflecting plate having a fine regular reflection pattern is interleaved between the master and the recording material, and the copying illumination light incident onto the recording material and regularly reflected light from the reflecting plate having the regular reflection pattern interfere together in the recording material thereby allowing the regular reflection pattern to be multi-recorded in a hologram having the reflection type volume hologram master copied in it.

Hologram fabrication process and fabricated hologram

The present invention is provided to enhance security of a volume hologram by recording therein individualized information such as information of character, numerical character, picture pattern, biometric matter and/or the like by irradiating laser light to the volume hologram thereby modifying the same physically or chemically, and is related to a laser marking hologram comprising a volume hologram layerincluding interference fringes recorded therein, wherein the volume hologram layerincludes information of character, numerical character, picture pattern, biometric matter, and/or the like recorded therein having a contrast between an irradiated portion and a non-irradiated portion thereof provided by selectively irradiating laser lightto the volume hologram layerin a manner to modifythe irradiated portion.

Laser marking hologram having a volume hologram with interference fringes using selective irradiation

The invention relates to a security-conscious hologram which can apply a sufficient three-dimensional appearance to a reconstructed image in both its vertical and horizontal directions, and which is difficult to illegally copy and easily told from any illegal copy forged from it, and a holographic process of recording it The hologram His of a combined reflection and volume type, wherein a subject image P is recorded, and minute reflection images F and O' from a light source are recorded at least in front of, or in the rear of, the subject image P, both in a reconstructible fashion, and a viewing position E is moved along a hologram surface, so that the subject image P and the minute reflection images F and O&#x2032; are viewable at varied relative positions.

Hologram and its holographic process

The invention provides a hologram in which a visually unidentifiable microtext or other micropattern of the order of 10 &#x3bc;m is recorded, and a process for the fabrication of the same. A volume hologram recording materialis located on the side of a reflection type volume hologram masteronto which copying illumination lightis incident, and the copying illumination lightincident onto the recording materialand lightdiffracted through the masterinterfere together in the volume hologram recording materialthereby copying the reflection type volume hologram master. In this case, a reflecting platehaving a fine regular reflection patternis interleaved between the masterand the recording material, and the copying illumination lightincident onto the recording materialand regularly reflected lightfrom the reflecting plate having the regular reflection patterninterfere together in the recording materialthereby allowing the regular reflection patternto be multi-recorded in a hologram having the reflection type volume hologram mastercopied in it.

The present invention provides an optical diffusion device, which can exhibit discontinuously different optical properties only in desired regions without creating any difference in grades and/or breaks, facilitate control of the optical diffusion properties, and prevent the occurrence of the stray light, as well as provides a projection screen and a design member, both using the optical diffusion device. An exemplary optical diffusion device according to this invention includes a base, and a cholesteric liquid crystal polymer layer provided on the base and composed of a plurality of diffusion regions arranged on a plane. A diffusion angle of one of the diffusion regions (e.g., first diffusion regions) of the cholesteric liquid crystal polymer layer is different from a diffusion angle of another of the diffusion regions (e.g., second diffusion regions).

Optical diffusion device, projection screen, design member and security medium

A main object of the present invention is to provide a transparent card with a hologram having the excellent design property and a high security property. The present invention achieves the object by providing a transparent card with a hologram, characterized by comprising a configuration with a transparent card substrate made of a resin transparent with respect to a visible light, and a hologram layer having a computer generated hologram part to function as a transmission type Fourier transform lens laminated.

Transparent card with hologram, and apparatus for recognizing transparent card with hologram

An object of the present invention is to provide an authenticity indicator that cannot be easily forged, that is clearly distinguishable, and that can be elaborately designed. An authenticity indicatoris in the form of a sheet and can be checked for its authenticity by observing the light reflected from it. The authenticity indicator comprises a first reflective layercomprising a reflective areathat reflects specified light, and a second reflective layerthat reflects specified light. The reflective area of the first reflective layer has a cholesteric liquid crystalline structure. The second reflective layer comprises a volume hologram.

Indicator for indicating authenticity

The present invention provides a see-through transmitting-reflecting projection screen excellent in transparency, capable of sharply displaying, on its both sides, identical or different images even under bright environmental light. A transmitting-reflecting projection screencomprises a reflection-type screenand a transmission-type screenThe reflection-type screenreflects a specific polarized component of imaging light projected. The reflection-type screendoes not reflect a polarized component, different from the specific polarized component, of the imaging light, and this polarized component passes through the reflection-type screenand the transmission-type screen

Transmitting-reflecting projection screen, and projection system comprising the same

The invention relates to a color hologram display an image of a three-dimensional object and a hologram image of a pattern of plane characters, images or the like are recorded in the same volume type hologram photosensitive material in a superposed or multiplexed fashion. A color hologram displaycomprising a combined reflection and volume type of single layer, wherein a color patternof plane characters, images or the like and a color three-dimensional subject image O&#x2033; are reconstructably recorded while spatially superposed one upon another.

Growing community of inventors

Tokyo, Japan

Masachika Watanabe