Polymer dispersion liquid crystal recording medium and method and apparatus for reproducing information

• US 5,933,201 A
• Filed: 11/18/1996
• Issued: 08/03/1999
• Est. Priority Date: 06/30/1992
• Status: Expired due to Term

• Current Assignee: Dai Nippon Printing Company Limited
• Original Assignee: Dai Nippon Printing Company Limited
• Inventors: Okabe, Masato
• Primary Examiner(s): Sikes, William L.
• Assistant Examiner(s): TON, MINH TOAN T
• Application Number:
  US08/751,255
• Time in Patent Office: 988 Days
• Field of Search: 349/1, 349/25, 349/86, 349/93
• US Class Current: 349/25
• CPC Class Codes: G02F 1/1334 based on polymer dispersed liquid crystals, e.g. microencapsulated liquid crystals
• CPC Class Codes: G02F 1/1354 having a particular photoconducting structure or material
• CPC Class Codes: G11B 7/25 containing liquid crystals

Abstract

The present invention relates to a polymer dispersion liquid crystal recording medium containing liquid crystals dispersed and fixed in resin, as well as to a method and an apparatus for reproducing information. In particular, when a medium as shown in FIG. 6 is used, the information recorded on the liquid crystal layer can be read with sufficient contrast by making the photoconductive layer (13) transparent to blue or ultraviolet light, and by making the wavelength of the reading light match the wavelength of the blue or ultraviolet light. When image reading is performed as illustrated in FIGS. 3 and 7, a white light source is used as light source (4), and a filter (5) is placed between light source (4) and the liquid crystal medium (20); thus, only blue or ultraviolet light enters the liquid crystal medium. After passing through the liquid crystal medium (20), the light is converted to an electric signal by a photoelectric converter (6).

Claims

1. An apparatus for reproducing information recorded on an information recording medium comprising an information recording layer having a liquid crystal layer and a UV-setting resin layer and arranged on an electrode layer, such that information is recorded on an information recording medium comprising an information recording layer having a liquid crystal layer and a UV-setting resin layer and arranged on an electrode layer, wherein an outer surface of said information recording layer is formed only by UV-setting resin, wherein a photosensitive member having a photoconductive layer is placed face-to-face to the information recording layer on a contact or non-contact basis, and information is written onto said information recording medium by light exposure under voltage application, whereby said information recording layer has a characteristic of transmitting ultraviolet light or blue light within a wavelength range of 320 to 500 nm, where an outer surface of said information recording layer is formed only by UV-setting resin,

wherein the apparatus comprises

an illuminating optical means for irradiating ultraviolet light or blue light within a wavelength range of 320 to 500 nm onto the information recording medium and

a photoelectric converter for detecting transmission light transmitted by the information recording medium, wherein the photoelectric converter has a window made of window material;

wherein a smectic liquid crystal with a memory property is used in the liquid crystal layer.

2. The apparatus according to claim 1, wherein an image forming lens made of quartz glass or fluorspar is placed between said information recording medium and said photoelectric converter.

3. The apparatus according to claim 1, wherein quartz glass or fluorspar is used as window material of said photoelectric converter.

4. A method for reproducing information recorded on an information recording medium, wherein the information recording medium is an information recording medium comprising a photosensitive member having a photoconductive layer, a liquid crystal layer, and a UV-setting resin layer and arranged on an electrode, wherein an information recording layer is provided which is integrally laminated so as to provide an integrated information recording medium, wherein information is written on the integrated information recording medium by light exposure under voltage application, wherein said photoconductive layer can pass light having a wavelength of 420 nm or more, and wherein a smectic liquid crystal with a memory property is used in the liquid crystal layer,

wherein said method comprises

irradiating blue light within a wavelength range of 420 to 500 nm onto the information recording medium as a reading light, and

reading the recorded information on the recording medium by transmission light,

wherein ultraviolet light is also used as a reading light in reproducing information recorded in the recording medium.

5. A method for reproducing information according to claim 4, wherein the photoconductive layer comprises a charge generating layer and a charge transport layer.

6. A method for reproducing information recorded on an information recording medium comprising the steps of:

forming an information recording layer having a liquid crystal layer and a UV-setting resin layer and arranged on an electrode layer, such that information is recorded on an information recording medium comprising an information recording layer having a liquid crystal layer and a UV-setting resin layer and arranged on an electrode layer, wherein an outer surface of said information recording layer is formed only by UV-setting resin, wherein a photosensitive member having a photoconductive layer is placed face-to-face to the information recording layer on a contact or non-contact basis, and information is written onto said information recording medium by light exposure under voltage application, whereby said information recording layer has a characteristic of transmitting ultraviolet light or blue light within a wavelength range of 320 to 500 nm, wherein a smectic liquid crystal with a memory property is used in the liquid crystal layer, where an outer surface of said information recording layer is formed only by UV-setting resin, and

reading the recorded information on the information recording medium by transmission light,

wherein ultraviolet light is irradiated onto the recording medium as a reading light,

wherein the reading light that is irradiated onto the information recording medium is ultraviolet light within a wavelength range of 320 to 400 nm.