CN1187898A - Liquid crystal optical storage medium with gray scale - Google Patents

Abstract

An optical storage medium with gray scale capability comprising: a plurality of facing substrates in series; alignment layers disposed on one or both sides of the substrates to give alignment layer pair(s) wherein at least one of the alignment layers of each of the alignment layer pair(s) is an optical alignment layer, and wherein the optical alignment layer(s) comprise anisotropically absorbing molecules or moieties; liquid crystal layers disposed between the alignment layer pair(s); wherein, each of the liquid crystal layer(s) comprises three or more alignment regions having three or more different alignment states; and, wherein the different alignment states are controlled by exposure of optical alignment layer(s) with polarized light of a wavelength or wavelengths within the absorption band of the anisotropically absorbing molecules or moieties therein, is described. The invention is also directed to compact disc, erasable compact discs, photographic storage devices, and storage displays.

Description

Liquid crystal optical storage medium with gray scale

The background of invention

The present invention relates to information storage, store more specifically to optical information.

Along with the application that computing machine and Voice ﹠ Video system constantly enlarge, wherein, information storage becomes problem rapidly, because need the information stored huge amount.Utilizing variety of way mainly is that return to zero has been stored information usually.Yet, use this system, on given surface area, can be subjected to very strict restriction by the information stored number.Therefore, those skilled in the art have sought new storage information approach, utilize them can more effectively utilize the space.Some class light storage devices appear on the market recently or are developed.Much the feature about optical storage medium is described in " Optical Recording " (Addison-Wesley (New York) 1990) of Alan B.Marchant work.

Magneto-optic memory technique accounted for recently and write/write the market of light data storage medium again.This medium uses magnetic field to change the orientation on the farmland in magnet-optical medium.Light from laser is used to heat partly this medium to being higher than its Curie temperature, makes that the farmland can reorientation in magnetic field.Use up and read this information, because the farmland that has been orientated can change the polarization state of the incident beam that is used to the information that reads.Usually 1 bit only can be stored in each farmland, because the variation of polarization is very little, therefore, is difficult to obtain sufficiently high signal to noise ratio (S/N ratio) so that reach higher bit level in each farmland.

Compact disk (Compact Disc, CD) and read-only memory (CD-ROM) optical storage medium be state-of-the-art, and occupied the consumer market securely.These medium for storing are only to read to store, and are limited to the application that need not change information.Importantly be to improve Media density and improve actuating speed.By making master with shorter ultraviolet ray, the density of CDs and CDROMs is about 4 times of present about 700 megabyte density.When keeping high s/n ratio again reading these more highdensity dishes, difficulty has just occurred.Developing and be used to read the more short wavelength diode laser (430nm-680nm) of these dishes to choose the more information of high-density medium.

A kind of method that is used for obtaining more storages and does not increase the bit density of dish is a plurality of dishes to be piled up and chosen by the focal position that light beam is read in change the information of each dish.This technology is proved by 100 microns spaces seam music CDs separately by two.

Write once and read compact disk (CD-R) technology is repeatedly used the medium and the system of a small amount of market supply.Here required is obtains reverse compatibility with CD and CDROM system.Based on dye adulterated polymkeric substance storage material is typical medium.For keeping reverse compatibility, dyestuff/polymkeric substance is spin-coated on the metal level.The high-density laser pulse has for good and all changed the refraction and the absorptive character of dyestuff/polymeric layer, and this causes the reflectivity of medium to change.

Burn long-pending Write once and read and repeatedly be used for big Database Systems in (WORM) technological model ground.This technology uses high power gas laser so that ablate concave point (pit) in metal level.This powerful technology is very vital, and has based oneself upon in big Database Systems, but is unsuitable for using the application of the CD and the CDROM of low-power infrared laser.

A kind of have write/optical storage medium wiped of write capability (CD-E) uses magnet-optical medium recently and drives again, but needs magnetic field and light field with writing information, therefore is not suitable for compact disk.Another kind of erasable optical storage medium uses the phase that changes these materials from the high density light pulse of the weak point of diode laser, becomes amorphous state from crystalline state.The reflection of amorphous state less (R～28%, with respect to crystallization phase 70%), and play a part " concave point ".Longer intermediate intensity pulse is used for the amorphous materials wraparound to crystalline state.The wavelength of laser diode is about 680nm.Having reported these media can reach up to 100 and write-read-circulation of wiping.

People are very interesting to the light arrangement aspect of the liquid crystal that carries out optical information and store.For example, United States Patent (USP) 5296321 has been described the optical recording media that can reversibly change the liquid crystal layer of orientation when reaching in being exposed to light based on transparent substrate, phototropic layer.This medium only can obtain two ordered states, uniformly and similar four (homeotropic) (being parallel and perpendicular to substrate) of returning line promptly.United States Patent (USP) 4780383 described a kind of more jumbo optical storage medium that has, and it is based on the cholesteric polymer phase on the selective reflecting of various wavelength light.This medium need simultaneously to arrange, to the carefulness adjustment of temperature and to the control of polymerization process, to obtain the multiplicity of the state of can distinguishing.

United States Patent (USP) 4886718 has been described reversible optical information and has been stored device, and it uses polymer liquid crystal as medium for storing, comprises the film of a liquid crystal trunk polymer.Carry out optical information with laser beam and store, change with the spatial order of generation liquid crystal trunk polymer and/or the selectivity of orientation.By producing scattering center with writing light beam, this medium can play binary message and store device.The also available polarized laser beam of this medium writes, so that produce the local modulation of refractive index, thus producing the reorientation of various degree, this is equivalent to continuous modulation mutually.The chance that this provides digital simulation to store.Holography method is used for storage information.Can be comprised the image reconstruction structure by information stored, for example theme (objects) or X-Y scheme rubber or printed leaves.

Using liquid crystal polymer is the high viscosity of medium as the major defect of optical storage medium.The initial orientation of medium needs some combinations of high temperature, external electric field, long annealing time or these processes.In addition, this medium is low and need external heating usually to the response that writes light beam.

Though these light system of storing has advantage compared with other record systems commonly used for the foregoing reasons, they are not gratifying entirely.It will be useful that a kind of like this practicality and optical storage medium cheapness are arranged, and they have the multiplicity of the state of can distinguishing, and the gray scale ability can be provided.Except storing numerical information, this medium can be useful to for example writing down and store photographic image.If this medium also has write capability again, this medium can constitute light and store display.The optical storage medium so that some information levels to be provided of stratification also can be useful, thereby has improved the information gross density in the medium.

Have been found that a kind ofly have multiple state, gray scale ability and the bed resolution distinguished improving the practical optical storage medium of information gross density, and in this disclosure.

Therefore, the purpose of this invention is to provide a kind of medium, utilize the multiple case (promptly more than 1 binary digit) of this medium information can be stored in the single farmland.

Another object of the present invention provides a kind of medium, the ability that it has gray scale and stores photographic image

Another object of the present invention provides a kind of optical storage medium that becomes multilayer, and each layer can be stored information with gray scale.

Another object of the present invention provides a kind of optical storage medium, and it can be addressed to provide light to store display.

Another purpose of the present invention is for the compact disk with read-only ability, repeatedly the compact disk of ability and the wiped compact disk of writing-keep ability for having provide optical storage medium in order to have Write once and read.

These and other advantage of the present invention will be become cheer and bright by the detailed description of following embodiment preferred.

Summary of the invention

Therefore, the present invention is the optical storage medium with gray scale ability, and it comprises: a plurality of end face substrates with one or more pairs of end faces that bunchiness is arranged; It is right to form alignment layer to last alignment layer to be placed on described end face, and wherein at least one alignment layer that each described alignment layer is right is the light alignment layer, and wherein the light alignment layer comprises anisotropic absorption molecule or component; Be placed on described alignment layer between liquid crystal layer, wherein each described liquid crystal layer comprises the arrange regional that three or more has three or more different ordered states, and wherein different ordered states is subjected to the control of described smooth alignment layer exposure, uses its wavelength at the absorption band of anisotropic absorption molecule or component or polarized light wherein during exposure.The present invention also relates to special light stores device and stores display.

The accompanying drawing summary

Fig. 1 illustrates the variation of guiding (director) angle of aligned twisted state between plane i and i+1.

Fig. 2 explanation has the plurality of rows column region of different aligned twisted states in liquid crystal layer of the present invention.

Fig. 3 explanation has the plurality of rows column region of different birefringence ordered states in liquid crystal layer of the present invention.

Fig. 4 explanation has the plurality of rows column region of different composite ordered state in liquid crystal layer of the present invention.

Fig. 5 is the xsect of the basic structure of explanation optical storage medium of the present invention.

Fig. 6 explanation is used for carrying out the exposure device that bias light is arranged with polarized light.

Fig. 7 explanation is exposed to four kinds of different polarization light vectors, to obtain four kinds of gray scales that do not have the optical storage medium of the present invention of aligned twisted state.

Fig. 8 is illustrated as the exposure device of obtaining the photographic image with 256 grades of gray scales.

Fig. 9 illustrates with the ultraviolet polarized light and carries out the exposure device that bias light is arranged.

Describe in detail

Exercise question is the United States Patent (USP) 5 of " Process for Aligning Liquid Crystal Media " (arranging the method for liquid crystal media), 032,009 and exercise question be the United States Patent (USP) 5 of " Process for Preparing Compositions Having Multiple Oriented Mesogens " (preparation has the methods of the mesomorphic composition of many orientations), 073,294 here is incorporated into as a reference.

" substrate ", we refer to the supporting structure of alignment layer.Substrate can be to provide any solid-state combination of expecting with the stratiform village of function for final optical storage medium.For example, substrate can be any combination of following material: crystal type or unformed silicon, glass, plastics (comprising polyester, tygon and poly-imines), quartz, indium-tin-oxide, gold, silver, silicon dioxide, poly-imines, silicon monoxide, anti-reflection coating, colour filter, polarization agent and phase compensation film.In practice, in these materials some are deposited on or are coated on infrastructural support structure example such as glass or the plastics.

" liquid crystal " refers to and has for example molecule of rod shape or dish shape of anisotropy geometric configuration, and their show between liquid and solid-state steady state (SS), and they have low molecular weight, promptly less than about 1500, preferably less than 1000.The liquid crystal that is suitable for the described invention in reaching is included in all liquid crystal described in the United States Patent (USP) 5032009; EM Industries, Hawthorne N.Y. supply with ZLI-5079, ZLI-5080, ZLI-5081, ZLI-5092, MLC-2016, the new perfluor liquid crystal (superfluorinated liquid crystals) of MLC-2019 and MLC-6043 statement.At the guest-main formulation (guest-host formulations) made with all types liquid crystal and anisotropic absorption dyestuff described in the United States Patent (USP) 5032009 also is useful.The preferred liquid crystal of the present invention is nematic crystal and comprises nematic crystal and the guest of anisotropic absorption dyestuff-main potpourri.

Preferred anisotropic absorption dyestuff is dichromatic arylazo in preparation guest-main potpourri, two (arylazos), three (arylazos), four (arylazos), five (arylazos), anthraquinone, part cyanine (mericyanine), methine, the 2-phenylazothiazole, 2-phenyl nitrogen idol benzene a pair of horses going side by side thiazole, Stilbene, 1, two (2-phenyl vinyl) benzene of 4-, 4,4 '-two (arylazo) Stilbene perylene and 4, the 8-diaminostilbene, 5-naphthoquinone dyestuff, other useful anisotropic absorption dyestuffs are the liquid crystal coupling dichroic dyes described in United States Patent (USP) 5389285.Arylazo, many (arylazos), and the Stilbene dichroic dye be most preferred to preparation guest-main potpourri.

Most preferred liquid crystal be 4-cyano group-4 '-alkyl biphenyl and 4-alkyl-(4 '-cyano-phenyl) cyclohexane and the guest-main potpourri of deriving by them.Concerning optical storage medium, particularly preferably be guest-main potpourri, and this optical storage medium is concerning requiring light absorptive the application that can wipe aspect the optical storage medium (CD-E).

Other useful liquid crystal comprise the polymerisable liquid crystal described in United States Patent (USP) 5073294 among the present invention; And at difunctionality methacrylate described in the United States Patent (USP) 4892392 and acrylate monomer liquid crystal.

Be applicable to that preferred polymerisable liquid crystal of the present invention is a polymerizable nematic monomer composition, comprise the monomer of (A) 20-80 at least a general formula of weight % (I), n is 10 in the formula, 12 or 14, (B) monomer of at least a general formulas of 80～20 weight % (I), n is 4,6 or 8 in the formula:

R n YIa CH ₃10-CO ₂-Ib CH ₃6-CO ₂R is CH among the-Shi ₃Or H, and Y be covalent bond or-CO ₂-.Synthesizing and being formulated in the United States Patent (USP) 5202053 of these nematic monomer compositions is described.Special nematic monomer used among the embodiment here is Ia and Ib.

Other preferred polymerizable liquid crystal compositions are the difunctionality methacrylate of top disclosed general formula I polymerizable nematic monomer composition and 0.1～30 weight %II and acrylate

R R ₁ p

IIa CH ₃ CH ₃ 6

IIb CH ₃ H 6

R is CH in the formula ₃Or H, R ₁Be CH ₃, H, Cl, OCH ₃And p=1-12.Synthesizing in people's such as Broer United States Patent (USP) 4892392 of these monomers is described, and the synthetic specific example of IIb is here received in the United States Patent (USP) for referencial use 5073294 and is described.Bifunctional monomer IIa is used for the embodiment of this paper.

Polymerizable nematic composition mixes to improve the reactivity of composition to photochemistry irradiation with a small amount of (being preferably 0.5～2.0 weight %) light trigger.The example of spendable light trigger is benzophenone and 2,2-dimethoxy-2-phenyl acetophenone.Can add so far in the liquid-crystal composition as the polyfunctional monomer of crosslinking chemical, its addition is the level of about 0.1～5 weight %.Polymerization inhibitor, for example methylnaphthohydroquinone also can add, and addition is the level of about 0.05～0.1 weight %, to suppress the premature polymerization of liquid crystal phase.

The polymerisable compound of fusion is phase in the middle of row when being chilled near room temperature.The behavior of middle phase is very similar to common nematic crystal.Therefore they are to arrange power with common liquid crystal phase mode response surface together.Yet in the time of under they are exposed to photochemical radiation (being the ultraviolet irradiation from black light or 200 watts of mercury lamps significantly), rapid polymerization takes place to be frozen into the alignment of liquid crystal phase in this liquid crystal media in polymer substrate.Therefore, in the present invention, polymerisable liquid crystal is to optical storage medium CD for example, and CDROM and WORM (those skilled in the art wish non-recoverable storage information therein) are preferred.

The term here " alignment layer (alignment layer) " is meant the layer of material on the substrate surface, the arrangement of liquid crystal layer during its no outfield of control.Here " common alignment layer " refers to a kind of alignment layer here, and it only arranges liquid crystal layer by the method beyond the optical mode.For example, with the poly-imines of mechanical polishing, the silicon dioxide of evaporation, the Langmuir-Blodgett film all has been used to arrange liquid crystal.

" light alignment layer (Optical alignment layer) " is meant a kind of like this alignment layer here, and it contains anisotropic absorption molecule or component, and after being exposed to polarized light, they will arrange liquid crystal.The light alignment layer can be processed by common mode, as mechanically friction before or after being exposed to polarized light.The anisotropic absorption molecule or the component of optical arrangement layer are when the absorbability that shows different value when the axle of different directions is measured.Anisotropic absorption molecule or component show absorption band at about 150nm between about 2000nm.The anisotropic absorption molecule of light alignment layer or component can covalent bondings in trunk polymer, they can be covalently bound in the host polymer chain with side group, they can appear in the polymkeric substance with the nonbonding solute, they can be the solutes in the adjacency liquid crystal layer, and can be absorbed on the common alignment layer to generate the light alignment layer, they can be by covalent bondings or directly are adsorbed on the substrate or on the alignment layer, to generate the light alignment layer.

Preferred light alignment layer has an absorption maximum between 150nm～about 1600nm.Preferred smooth alignment layer has an absorption maximum between 150nm～about 800nm.Most preferred smooth alignment layer is having an absorption maximum between 150nm～400nm or between 400nm～800nm.

Preferably, optical storage medium of the present invention has two or more smooth alignment layer, they 150 and 1600nm between absorption maximum is arranged, differ by more than 10nm, and more preferably differ by more than 50n.More preferably, the absorption maximum of light alignment layer differs by more than 10nm between 150～800nm, preferably differs by more than 50nm.Most preferably, the absorption maximum of light alignment layer differs by more than 10nm between 150～400nm or between 400～800nm, is preferably greater than 50nm.The difference that absorbs between the light alignment layer makes and can each liquid crystal layer is addressed by selecting the polarization light wavelength suitably.

Preferred light alignment layer has to be dissolved in the polymer substrate carrier anisotropic absorption molecule or the component as the nonbonding solute.These are called guest-key light alignment layer.They are to prepare by the organic material thin layer that coating one deck on substrate contains anisotropic absorption molecule or component.Typical situation is that the anisotropic absorption molecule is dissolved in the solution with polymeric material.This solution typically is coated onto on the substrate with revolving the method for watering then.Afterwards coating is dried by the fire in stove and burn to remove residual solvent and to carry out final curing.

Being used to prepare among the polymkeric substance of guest-key light alignment layer, poly-(methyl methacrylate) arranged, poly-(amine-6,6), polystyrene, polyvinyl alcohol (PVA), epoxy-amine polymkeric substance and poly-imines.Preferred polymkeric substance is poly-imine polymer concerning the light alignment layer.The preparation of poly-imines is at D.Wilson, and H.D.Stenzenberger reaches P.M.Hergenrother and edits, and by Chapman andHall, is described among " Polyimides " of New York (1990) version (" poly-imines ").The special poly-imines that is used to prepare the light alignment layer is 3,4,3 ', 4 '-condensation product of benzophenone dianhydride and oxygen (4,4 '-dianiline); MicroSi, Inc., Phoenix, the poly-imines of the SPI2000 of Arizona85044 supply; And Brewer Science, Rolla, the NISSAN7311 of MO supply and 7210 poly-imines.

The anisotropic absorption molecule can be covalently bound on the polymkeric substance.For example, poly-(amic acid) as the precursor that gathers imines can make by the anisotropic absorption molecule being covalently bound on poly-(amic acid) polymer chain.This preparation method is typically by mixing dianhydride (comprising the anisotropic absorption molecule as one of two kinds of active components) with diamines, and allows these materials for example carry out polymerization in N-Methyl pyrrolidone or the tetrahydrofuran at solvent and make.Then this pre-polymer solution is coated on the substrate and in stove and toasts, to generate final poly-imines light alignment layer.

Perhaps and preferably, the light alignment layer prepares on the substrate by for example poly-imines of common alignment layer is coated to.The anisotropic absorption molecule is dissolved in the liquid crystal media to make guest-main potpourri.When with guest-main potpourri when common alignment layer contacts, the anisotropic absorption molecule is absorbed from the teeth outwards and forms the light alignment layer.The light alignment layer that makes in this way is preferred to optical storage medium, and this medium requires light absorptive when being used for wiping optical storage medium (CD-E).

Perhaps, the light alignment layer is by being applied to for example poly-imines of common alignment layer on the substrate and the anisotropic absorption molecule is dissolved in the solvent makes.When being coated in this solution on the common alignment layer, the anisotropic absorption molecule is adsorbed from the teeth outwards, forms the light alignment layer.

Perhaps, the light alignment layer directly is coated on the substrate by the coating liquid with the anisotropic absorption molecule and makes.The anisotropic absorption molecule is adsorbed to and forms thin layer on the substrate, and perhaps they can be covalently bound on the substrate.

In the light alignment layer of making optical storage medium, preferred anisotropic absorption molecule is dichromatism arylazo, two (arylazo), three (arylazos), four (arylazos), five (arylazos), anthraquinone, part cyanine (mericyanine), methine, 2-phenylazothiazole, 2-phenylazobenzene a pair of horses going side by side thiazole, Stilbene, 1, two (2-phenyl vinyl) benzene, 4 of 4-, 4 '-two (arylazo) Stilbene, perylene and 4,8-diaminostilbene, 5-naphthoquinone dyestuffs.Other anisotropic absorption materials that are suitable for are liquid crystal coupling dichroic dyes of describing in United States Patent (USP) 5389285.

The preparation that above listed anisotropy is received absorbing material is known, for example people such as Huffman at United States Patent (USP) 4565424, people such as Jones are at United States Patent (USP) 4401369, Cole, Jr. wait the people at United States Patent (USP) 4122027, people such as Etzbach are at United States Patent (USP) 4667020, and people such as Shannon is shown in the United States Patent (USP) 5389285.

The preferred anisotropic absorption molecule and the component that are used for all types light row type layer are arylazo, many (arylazos) and Stilbene dyestuff.Concerning the guest-key light alignment or liquid crystal guest-main potpourri of preparation light alignment layer, the liquid crystal para-dye is preferred.Between the light alignment layer of 150～400nm, arylazo dye well Stilbene dyestuff is most preferred concerning absorption maximum.Between the light alignment layer of 400～800nm, many (arylazo) dyestuff is most preferred concerning absorption maximum.Most preferred many (azo) dyestuff is a diazonium diamine (diazodiamine) 1; Most preferred Stilbene dyestuff is 4,4 '-the diamido Stilbene, 2; And most preferred arylazo dyestuff is monoazo diamine (monoazodiamine) 3 (seeing Table 1).The preparation of dyestuff 1 is described in United States Patent (USP) 5389285; The synthetic of dyestuff 3 is described in an embodiment; And 4,4 '-diamino-stilbene is by Aldrich Chemical Co., Milwaukee, and WI. supplies in a large number.

" alignment layer is to (alignment layer pairs) " is meant two alignment layer that the identical liquid crystal layer of control is arranged here.

" arrange regional (alignment region) " refers to the continuum of the liquid crystal layer with aligned identical attitude.Arrange regional can be 0.01～10 ⁶μ m ²(μ m is equivalent to micron).The scope of preferred arrange regional is from 0.1 to 10 ⁶μ m ²The scope of most preferred arrange regional is from 0.1 to 100 μ m ²In liquid crystal technology, defined here arrange regional often is called " farmland ".

Yet, in the information storage technology, the farmland be used to describe any homogeneous area (bubble, colored spots, reflecting surface, or the like), binary message of its definition storage unit.Here arrange regional will use as above-mentioned definition, and the farmland will be used to be described in the homogeneous area in medium for storing rather than the liquid crystal media.Table 1

Dyestuff # structure 1

2 3

" local arrangements direction (the direction ofthe local alignment) " of liquid crystal layer is the mean direction that is injected into mesomorphic (mesogen) system on alignment layer plane.

" ordered state " refers to three own types of arrangement: birefringence is arranged, aligned twisted and unite arrangement.Every class arrange all have three kinds or multiplely distinguish, recognizable state.But each arrange regional in liquid crystal layer of the present invention is accepted the ordered state of a kind of arrangement type and a kind of subregion.All arrange regionals not all must have unique ordered state.Identical ordered state may take place repeatedly in different arrange regionals in whole liquid crystal layer.

With regard to " distortion alignment ", the difference that it refers to arrange regional is the variation of twisting.And " distortion " or " aligned twisted " refer to, between alignment layer between the local arrangements direction of liquid crystal layer, change in a continuous manner to other layers by an alignment layer.As shown in Figure 1, the sub-angle γ that leads of the projection in alignment layer i _i, be different from projection in the alignment layer i+1 angle γ that leads _I+1, consequently, local liquid crystal projection guiding is by γ _iBe changed to γ continuously _I+1, in liquid crystal layer, generate a kind of distorted-structure.For purposes of the invention, twist angle γ _t=γ _I+1-γ _iCan change to 360 degree from-360 degree.For obtaining greater than 90 ° or less than-90 ° twist angle, can add chiral dopant for example CB-15 (EM Chemicals, HawthorneNY).

As twist angle γ _tEqual at 0 o'clock, not distortion in liquid circle medium, this medium is known as and is arranged in parallel.The present normally used γ of most of liquid crystal display applications _tEqual 90 or-90 degree.

In a kind of aligned twisted state, each arrange regional can have a distortion rather than zero, and the distortion value changes between the zone in the zone.Further stipulate, the projection of local liquid crystal guiding on an alignment layer is to be identical with direction on all farmlands of this alignment layer, and the projection of local liquid crystal guiding on second alignment, its direction changes each arrange regional, makes the distortion value change.Fig. 2 explanation has the liquid crystal layer of plurality of rows column region, and the distortion value of these arrange regionals changes.Solid line in each arrange regional is illustrated in liquid crystal guiding on this plane at plane i and i+1.How dotted line of representing to lead enters another planarization process from a planar row and rotates.For example, regional t ₁The distortion value be 180 °, and t ₂The distortion value be 0 °, t ₃The distortion value be 270 °.

Fig. 2 makes twist angle produce the composite means of bigger variation in order to explanation by control light alignment layer.As indicated above, for obtaining to need to add chiral dopant so that in liquid crystal media, introduce the nematic structure of distortion greater than 90 ° or less than-90 ° distortion.The chiral dopant that in liquid crystal media, has a uniform concentration generally, liquid crystal media will have uniform inclination.This inclination will determine a scope, and in this scope, the distortion angle that causes with the light aligning method changes and will take place.If (this can generate uniform twist angle γ the chiral dopant of uniform concentration _t), but then twist the variation range photocontrol at γ _t± 90 °.For example, if select the chiral doping agent concentration, make γ _t=270 °, so, it will be 180 °～360 ° that the distortion of photocontrol changes.

" birefringence ordered state (birefringent alignment state) " is meant that the arrange regional in the liquid crystal layer is different because of birefringent variation.The distortion of each arrange regional is 0 (γ _t=0 degree), son changes on direction concerning each arrange regional in the projection of alignment layer but liquid crystal leads.Liquid crystal layer with some birefringence ordered states has been described among Fig. 3.Arrange regional b ₁, b ₂And b ₃Have different 60 ° respectively with respect to plane i, local arrangements guiding of 0 ° and 90 °.

" assembled arrangement state (combination alignment state) " be meant, in liquid crystal layer one and a plurality of arrange regional are different because of the change aspect distortion and birefringence.Therefore, for each arrange regional, distortion can change in certain tolerance, and the projection of local liquid crystal guiding on each alignment layer can change on direction.Fig. 4 explanation has the liquid crystal arrangement layer of plurality of rows column region, and the alignment area has different assembled arrangement states.Local liquid crystal guiding all can be different in the projection of two alignment layer.Arrange regional c ₁, c ₂And c ₃All have different distortion values and different local arrangements guiding.For example, c ₁Distortion be 45 °, arrange guiding with respect to the background of i and change 90 °; c ₂Distortion be 0 °, 0 ° of the variation of guiding son; c ₃Distortion be 270 °, 0 ° of the variation of guiding son.In addition, the scope of each liquid crystal layer twist angle depends on the inclination of liquid crystal media.

" gray scale ", can encode with three or more value in each farmland that refers to optical storage medium.For example, if can encode with N probable value (N is an integer) in each farmland, then each farmland must have N native mode, and these states can be measured with the detection architecture that is suitable for this special applications.The size of N value is measured by the sensitivity of optical storage medium and/or the sensitivity of detection architecture.

Traditionally, the N probable value is represented with 2 exponential.If N=16 probable value, then these 16 values (thereby there are 16 native modes on each farmland in medium) can be with 2 ⁴Represent and be called 4 bit gradation.Term bit representative is used for getting 2 exponential of whole probable values.For example 0 bit will be represented 1 possibility encoded radio, 1 bit=2 possibility encoded radios ..., j bit=2 ^jIndividual possibility encoded radio.

In the great majority of optical storage medium were used, the native mode on each farmland caused the transmission incided on the photosensitive detector or the variation of reflection flux.For each native mode, there are intrinsic transmittance or light reflection levels.The solid-state detector of based semiconductor and human eye are a few of photosensitive detector.Each detection architecture must be machined for transmitted light or reflected light signal the information of decoding.

Under the situation of solid-state detector, electronics processing changes light energising level into deciphered by computing machine binary number (2 powers).Computing machine is handled (farmland of single treatment) serially or is handled (a plurality of farmlands of single treatment) binary number concurrently by each farmland, and generation information, and this informational needs goes to finish by the task of sequencing.

Under the situation of human eye, the intrinsic light level on each farmland is generated photo image by the parallel processing of human brain.Concerning human brain, each farmland itself is not highly significant, but from the significant information of overall generation of each farmland transmission or the light level that reflects, this information is deciphered by human brain.

Most of optical storage mediums only illustrate 1 bit information, and this information can be carried out record in an independent farmland.Consequently, two native modes only being arranged is possible (promptly in a binary number system 0 or 1).Therefore, in this medium, number 16 to be stored, 4 farmlands will be needed.Yet if each farmland has 16 native modes, a single farmland can be stored and the required the same number of number in 4 farmlands in 1 bit medium.Therefore, we have improved storage density 4 times effectively.Be with this to argue in its consequent, if each territory can provide 2 ^kIndividual measured state, then the medium storage density can improve k doubly.

In the context of the present invention, each liquid crystal arrangement zone in optical storage medium can be with intrinsic birefringence ordered state, and aligned twisted state or compound ordered state are encoded.If polarized light is by medium transmission or reflection, by polarizer, then intrinsic ordered state can change detected light level then.For example, if we use the aligned twisted state to each arrange regional.Then there is the intrinsic light level that is detected in the aligned twisted attitude, their distortion value is restricted to the quadrant (0～90 degree, 90～180 degree, or the like) of whole 360 degree distortions.To quadrant and N intrinsic distortion alignment, there be 90/N possible detected light level.Therefore, can there be gray scale in each arrange regional in medium of the present invention.Birefringence and compound ordered state for being adopted among the present invention can produce similar arguement.

For in medium, obtaining required gray feature, need be more than two ordered states.Preferred light medium for storing of the present invention described here has between 4 to 2000 ordered states.

Below with reference to the accompanying drawings one embodiment of the invention are described in detail.Fig. 5 is the cross-sectional view of explanation optical storage medium basic structure of the present invention.A series of substrate 1 usefulness alignment layer 2 apply in its one or both sides.To be coated with substrate then banks out in order and suitably separates with the spacer (not shown).These a series of substrates can seal (except the entry and exit) to make a box with sealed compound at its peripheral (not shown).Use required liquid crystal with this box filling then, Generation Liquid crystal layer 3 is with rear enclosed filling exit and outlet.The extra two coated substrates of during these are a series of each make and form the repeat body 4 that comprises extra liquid crystal layer.The number of repeat body can be from X=0 to about 20, and only be confined to the ability of each liquid crystal layer being carried out addressing.

Finish by using special spacer at the interval of substrate.Spacer is an inert particle, and its really big or small (one direction at least) is complementary with required box is thick.Glass wool roll (originating from EMIndustries, Inc., Hawthorne, New York), rubber and polystyrene spherical emulsion particle, film evaporation or sputter are the sources of spacer.Spacer contacts certain control enclosure distance by making substrate with the direct of spacer particle, thus and maintenance substrate distance.Make before substrate lumps together, spacer can scatter slightly and equably in the whole zone that comprises demonstration, and perhaps spacer is added in the bonding agent and only is coated onto on the packing ring sealing that is formed by sealed compound.The other mechanism that is used to control spacing puts at the periphery of box well to have determined the thickness thin film packing ring.Through the thin polymer film of well-characterized for example Mylar (mylar) or Teflon (teflon) (originate from Du PontCo., Wilmington, Delaware) and the aluminium film can be used for this purpose.

The sealing of substrate can be carried out with curable adhesive, and bonding agent is used to the periphery of box, and makes it to be filled any opening or hole by kapillary before curing.Quik-Stik epoxy resin (originate from GC Electronics, Rockford, Illinois) and Norland optical adhesive (originating from Norland Products Inc., New Brunswick, New Jersey) be used for this purpose.Under the soft situation of showing of the large tracts of land of using thermoplasticity polymerization substrate, can adopt the heat seal method, various thus substrates can utilize heat and pressure and be fused to together.

As appreciable by Fig. 5, each liquid crystal layer has corresponding alignment layer right, and the latter controls the arrangement of liquid crystal layer.In the present invention, at least one alignment layer of each alignment layer centering is the light alignment layer.The different arrange regionals 5 of liquid crystal layer have three or more ordered state, and this causes gray scale.In Fig. 5, the specific arrangement state of arrange regional 5 can be different twisted state, and birefringence state or assembled arrangement state, or the combination of all three class states are shown in Fig. 2-4.Ordered state is to control by being exposed in the selection zone of light alignment layer with polarized light.Be complementary and can carry out selectively addressing by absorption characteristic each liquid crystal layer with suitable polarized light wavelength and corresponding light alignment layer.With polarized light light alignment layer exposure can be carried out before or after the system box, with carry out before or after the liquid crystal media layer contacts.

For obtaining the optical storage medium of display gray scale, need light processing so that in liquid crystal layer, store information with gray scale.This job operation comprises: a) in the arrange regional of selecting, the right one or more light that make alignment layer are discharged to layer and are exposed under the polarized light with vector, wherein the light alignment layer comprises anisotropic absorption molecule or component, and the polarization light wavelength is in the absorption band of anisotropic absorption molecule or component; And the light alignment layer of wherein having exposed the polarized light vector+θ and-the θ angle in and along light alignment layer plane, the guiding liquid crystal media arrangement; B) in the plane of light alignment layer, the vector of polarized light is rotated to a new position; C) repeating step a).In liquid crystal layer, set up another ordered state with the exposure each time that new polarized light vector carries out.

The exposure of selection zone under polarized light of the light alignment layer that alignment layer is right, and that other alignment layer are kept is fixing, has formed the ordered state of distortion.

The exposure of the equivalent of selection zone under polarized light of two light alignment layer that alignment layer is right produces the birefringence ordered state.

When the selection zone of two right light alignment layer of alignment layer is exposed to polarized light unequally, produce compound ordered state.

To " polarized light ", we are meant light by elliptic polarization, make light come bigger along the polarization on the axle (being called main shaft) compared with perpendicular axle (being called countershaft).For purposes of the invention, preferred polarization is a linearly polarized photon, and this light is along an axle (main shaft) the biggest ground polarization, along countershaft then seldom or do not have a polarized component.In the present invention, polarized light preferably at 150～about 1600nm, most preferably has one or more wavelength at 150～2000nm in the scope of 150～about 800nm.Most preferably this polarized light is between 150～about 400nm or between 400nm～800nm.Preferred light source is a laser, argon for example, helium-neon, or helium-cadmium.Other preferred light source are mercury arcs, xenon lamp, and black light.Using low power laser or when arranging little alignment area, need focus the beam on the light alignment layer.

The method can be used for forming very a large amount of intrinsic ordered states to obtain the high resolving power of gray scale in liquid crystal media.The preferred number of ordered state is between 4～2000, most preferably is between 16～360.A back number of ordered state makes the high resolution picture image be stored in this medium.The method makes that also the density of the arrange regional on each unit plane is very high.The size in preferred arrangement zone is at 0.1～100 μ m ²Scope between.

Utilization all liquid crystal medias described in United States Patent (USP) 5032009 reach at United States Patent (USP) 5073294 describable polymerisable liquid crystals (these patents are introduced into as a reference), and this method can be used to obtain gray scale.For utilizing nematic crystal, be dissolved in the guest who contains for example above-mentioned azo of anisotropic absorption molecule or the polyazo dye-main potpourri in the nematic crystal; And polymerisable nematic crystal, to obtain gray scale, the method is particularly useful.The liquid crystal that preferably is specially adapted to this method comprise 4-cyano group-4 '-alkyl biphenyl, 4-alkyl-(4 '-cyano-phenyl) cyclohexane and the guest-main potpourri of deriving by them.A liquid crystal layer (x=0)

Preferred specific embodiments of the present invention (Fig. 5) comprises a liquid crystal layer and does not have repeat body 4 (X=0).This single liquid crystal layer has one or two light alignment layer.Some kinds of optical storage medium alternative structure are arranged in this specific embodiments.

A kind of preferred optical storage medium has a light alignment layer, and the second order layer is the general alignment layer of afterglow.In the selection zone of liquid crystal layer, this liquid crystal layer has three or more aligned twisted state, is more preferably between 4～2000 aligned twisted states.In the absorption band of light alignment layer, the light alignment layer is exposed in selecting the zone and makes liquid crystal guiding on this plane, rotate in the polarized light, and that second surface is kept is fixing.The distortion value is controlled, and changes to another zone (as mentioned above) by a zone.

Another preferred light medium for storing has two light alignment layer, and liquid crystal layer is selecting the zone to have three or more aligned twisted state, more preferably 4～2000 aligned twisted states.In order to accomplish this point, available polarized light is arranged a light alignment layer uniform exposure so that set up the uniform figure viewed from behind on a light alignment layer.The second smooth alignment layer is changed the vector of polarized light in selecting the zone simultaneously with polarized light exposure, this makes liquid crystal guiding rotate on second surface.This distortion value can Be Controlled (as mentioned above).

Another preferred optical storage medium has two light alignment layer and three or more ordered state, 4～2000 ordered states more preferably, and the latter has different local birefringence axles in the plane of alignment layer.This can be by carrying out the exposure of equivalent and change the polarized light vector simultaneously accomplishing to the selection zone of two light alignment layer with polarized light.

Another preferred optical storage medium has two light alignment layer that are equal to and three or more compound ordered state, more preferably between 4～2000 compound ordered states, the latter has different local birefringence axles and different aligned twisted states in the alignment layer plane.This point can be accomplished by make each light alignment layer not be equal to exposure and change the polarized light vector simultaneously with polarized light.

Another preferred optical storage medium has two two different light alignment layer that absorption characteristic is different in the selection zone of liquid crystal layer, and three and a plurality of different aligned twisted state, more preferably 4～2000 aligned twisted states.A light alignment layer is carried out uniform exposure with first wavelength of polarized light arranges to set up homogeneous background.The second smooth alignment layer is exposed at second wavelength of selecting the zone with polarized light, and change the polarized light vector simultaneously.This makes liquid crystal guiding produce rotation in second surface.The distortion value can be controlled as mentioned above.

Another preferred optical storage medium exists two two do not share the same light alignment layer and three or more birefringence ordered states that its absorption characteristic is different, is more preferably 4～2000 birefringence ordered states.A light alignment layer is changed the polarized light vector simultaneously selecting the zone to expose with polarized light, second alignment layer exposed at second wavelength of selecting the zone with polarized light.This makes is selecting zone liquid crystal guiding on two upper surfaces to produce independently rotation.

Another preferred light medium for storing exists two two different light alignment layer and three or more ordered states that its absorption characteristic is different, is more preferably 4～2000 compound ordered states.A light alignment layer selecting the zone to expose with polarized light, is changed the vector of polarized light simultaneously, again the second smooth alignment layer is exposed at second wavelength of selecting the zone with polarized light.This makes is selecting zone liquid crystal guiding on two surfaces all to produce independently rotation.

Another preferred optical storage medium with a liquid crystal layer has the electrode of having made wiring pattern (patterned) on one or more substrates.This substrate can for example be the glass plate that indium-Xi-oxide (ITO) covers.With the common slabstone typography to ITO electrode patterning case.The electric field that utilization applies can carry out addressing in the selection zone of optical storage medium and read.This can simplify and/or quicken write/read operation.

Optical storage medium described in the present invention has a lot of application in data storage.It can be used as high density CD, CD-R, and CD-E, photographic image is stored the data storage medium of display, and is used as the data storage medium of two or more liquid crystal layer joint effects.Some application of the optical storage medium of this invention are discussed below.

Have the optical storage medium of liquid crystal layer that one deck has coding aligned twisted state (this suitable digital signal) and can be used as compact disk (CD) or compact disk read-only memory (CDROM).Optical storage medium is sandwiched in a pair of polarizer.With reading the numerical information of having encoded by the light beam of each arrange regional and with suitable photodetector record transmitted light or intensity of reflected light.The density information that has write down is as the function of the position of arrange regional and transmitted light or intensity of reflected light size and be further processed.

Have the optical storage medium that one deck has the liquid crystal layer of coding aligned twisted state and can be used as repeatedly (WORM or CD-R) memory of Write once and read.Selection regional exposure by making the light alignment layer with polarized light, the method that changes the polarized light vector are simultaneously finished coding step.The exposure area is equivalent to needed number information.The numerical information of having encoded as for have the CD of aligned twisted state described, can read repeatedly.

Having optical storage medium that one deck has the liquid crystal layer of coding aligned twisted state can be used as to have and writes-the wiped compact disk of write capability (CD-E) again.Ordered state in each zone makes it to change by changing the above-mentioned polarized light direction vector that writes light beam.Store new information then, and as for have the CD of aligned twisted state described, can read this fresh information subsequently.

Photo image can be stored in and have in the optical storage medium of liquid crystal layer that one deck has coding aligned twisted state.The image that does not have polarizer is sightless.This optical storage medium be placed between a pair of polarizer can vision mode read this photo.Be parallel to each other or the absorption axle of vertical a pair of polarizer can be read positive or negative photographic image with having.The interesting performance of another of this medium is that these images have very wide visual angle.The LCD image typically has narrow visual angle, and this is from commercial LCD, and counter and foldable computer (laptopcomputers) can be known.

Have the optical storage medium of liquid crystal layer that one deck has coding birefringence ordered state (this is equivalent to numerical information) and can be used as compact disk (CD) or compact disk read-only memory (CD-ROM).The numerical information of having encoded be can read with polarized light, and transmitted light or catoptrical differing measured with the appropriate combination of polarizer and/or interferometer technique by each arrange regional.The strength information of having encoded is as the function of arrange regional position and transmitted light or catoptrical numerical value and be further processed.

Have the optical storage medium that one deck has the liquid crystal layer of coding birefringence ordered state ability and can be used as repeatedly (WORM or CD-R) memory of Write once and read.By exposing equally and the way that changes the polarized light vector simultaneously can be finished coding step in the selection zone that makes two light alignment layer with polarized light.The exposure area is equivalent to required numerical information.This numerical information of having encoded can be read out repeatedly as described to the CD with birefringence arrangement attitude.

Having the optical storage medium that one deck has the liquid crystal layer of coding birefringence ordered state ability can be as wiping compact disk (CD-E).Can change ordered state in each zone by changing the above-mentioned method that writes the polarized light direction vector of light beam.Can store new information then and can read subsequently, as described CD with birefringence ordered state.

Photographic image can be stored in and have in the optical storage medium of liquid crystal layer that one deck has coding birefringence ordered state.With the appropriate combination of polarizer and/or interferometer technique, holographic technology for example, mode that can vision is read this photo.

Have the optical storage medium that one deck has the liquid crystal layer of coded combination ordered state (this is equivalent to numerical information) and can be used as compact disk (CD) or compact disk read-only memory (CDROM).This numerical information of having encoded is with the light beam by each arrange regional, and writes down transmitted light or catoptrical phase and/or intensity and read with the appropriate combination of interferometer technique, polarizer and photodetector.The function of the optical information that has write down as the size of arrange regional position and intensity in transmission or reflection strength further processed.

Have the optical storage medium of liquid crystal layer that one deck has the compound ordered state ability of coding and can be used as repeatedly (WORM or CD-R) memory of Write once and read.Vicissitudinous polarized light vector of apparatus and the writing light beam and can carry out coding step of exposure area (this is equivalent to needed number information).The numerical information of having encoded is can read several times as described to the CD with compound ordered state.

Having the optical storage medium that one deck has the liquid crystal layer of the compound ordered state ability of coding can be as can wiping compact disk (CD-E).Can change ordered state in each zone by changing the above-mentioned direction that writes the polarized light vector of light beam.Store fresh information then and also can read subsequently, as described CD with compound arrangement attitude.

Photographic image can be stored in and have in the optical storage medium of liquid crystal layer that one deck has the compound ordered state of coding.Photo can be used to relate to the appropriate combination of instrument technology and polarizer and read in the mode of vision.Positive or negative photographic image can be used to relate to the suitable arrangement of instrument equipment and/or polarizer and read.

Having one or more layers optical storage medium with liquid crystal layer coding distortion, birefringent and compound ordered state mixture ability can be used as and can wipe compact disk (CD-E).By changing the above-mentioned polarized light direction vector that writes light beam, can change the ordered state in each zone.Store fresh information then, can as described, read subsequently CD with compound ordered state.

Have the optical storage medium that one deck has the liquid crystal layer of aligned twisted state, birefringence ordered state or compound ordered state and can be used as the storage display.Previous described photographic image is exposed to subsequently in the polarized light and can becomes new image.When visual pace of change changed greater than video speed, this display can be used for movie or television.When being slower than video speed, light is stored display and be can be used for variable signal, for example indicates wagon flow.As mentioned above, the interesting advantage of this optical storage medium is obtainable high visual angle, and this point is uncommon arriving in common LCD.Two liquid crystal layers (X=1)

In preferred embodiments, the optical storage medium of the present invention with gray scale comprises two layers of liquid crystal layer that has a repeat body 4 (X=1 among Fig. 5).These two liquid crystal layers internally can have one or two light alignment layer in their alignment separately.This light alignment layer can have identical or different absorption characteristics.Preferably the first order layer is to having one deck light alignment layer at least, the latter has anisotropic absorption molecule or the component that has absorption maximum at 150nm～400nm, and the second order layer is to having at least one light alignment layer, and the latter has anisotropic absorption molecule or the component that has absorption maximum at 400nm～800nm.Concerning the optical storage medium in the present embodiment, there are some alternate design.

In having the preferred light medium for storing of two liquid crystal layers, each alignment layer is to having a light alignment layer, and the second order layer is afterglow, common alignment layer.The light alignment layer by preferred coated on the surface of two outside substrates.Common alignment layer is by on the substrate in back-to-back being coated in.This liquid crystal layer has three or more aligned twisted state in the selection zone of each liquid crystal layer, be more preferably 4～2000 aligned twisted states.The light alignment layer is exposed in selecting the zone under the polarized light in the absorption band of light alignment layer and makes liquid crystal guiding rotate on this surface, and second surface remains unchanged.Each alignment layer can be exposed independently of one another from the exposure of the either side of complete box by before the formation of complete box, exposing or passing through.Distortion value Be Controlled, and as foregoing, change to another zone from a zone.

In having another preferred light medium for storing of two liquid crystal layers, each alignment layer is to having a light alignment layer, and second common alignment layer that alignment layer is an afterglow.Each light alignment layer has different absorption maximum, to different optical wavelength sensitivities, and preferably is painted on the surface of two outer substrates.Common alignment layer is by on the substrate in back-to-back being coated in.This liquid crystal layer has three or more aligned twisted state in the selection zone of each liquid crystal layer, and is preferably 4～2000 aligned twisted states.The light alignment layer is exposed in selecting the zone under the linearly polarized photon in the absorption band of light alignment layer and makes liquid crystal guiding rotate on this surface, and second surface remains unchanged.Expose or, each alignment layer can be exposed independently of one another by before constituting at complete box by exposure from complete box either side.Distortion value Be Controlled, and change to another zone from a zone, as foregoing.

Another kind has the preferred light medium for storing of two liquid crystal layers, and each alignment layer is to having two similar light alignment layer, but each alignment layer is to having different absorption maximum, as described above.These liquid crystal layers each layer in selecting the zone all has three or more ordered state, and is preferably 4～2000 aligned twisted states.For accomplishing this point, the light alignment layer wavelength that each alignment layer is right is that the absorption band of anisotropic absorption molecule or component or the polarized light within it carry out uniform exposure and arrange with the homogeneous background of setting up on a light alignment layer.The polarized light that the second smooth alignment layer is exposed to similar wavelength changes polarized light vector in selecting the zone down simultaneously, will make liquid crystal guiding be rotated on second surface.Can control the distortion value as mentioned above, and make two kinds of different wave lengths using up that each liquid crystal layer is arranged independently.

Another kind has the preferred light storage medium of two liquid crystal layers, and each alignment layer is to having two similar light alignment layer, but each alignment layer is to having different absorption maximum.Each all has three or more birefringence ordered state to these liquid crystal layers in selecting the zone, and is preferably 4～2000 birefringence ordered states.For accomplishing this point, right two the light alignment layer of alignment layer by the exposure of the polarized light of the wavelength in their absorption bands, and change the polarized light vector simultaneously in selecting the zone.The second order layer is to can be in a similar manner carrying out addressing with second wavelength of polarized light.Before or after box constituted, two different wave lengths that this liquid crystal layer can be used up were arranged independently of one another.

Have in the preferred light medium for storing of two liquid crystal layers at another, each layer has two light alignment layer with different absorption characteristics.These liquid crystal layers have three or more compound ordered state in the selection zone of each liquid crystal layer, more preferably 4～2000 aligned twisted states.Selecting the zone to expose a light alignment layer with polarized light, and changing the polarized light vector simultaneously, selecting the zone to expose on the second order layer with second wavelength of polarized light.This makes liquid crystal layer guiding all select the zone to rotate independently on two surfaces.Second order is to repeating this operation.Before constituting, expose, or expose, and these alignment are exposed independently of one another by either side to complete box at this complete box.

Another has the preferred light medium for storing of two liquid crystal layers, has the electrode of making wiring pattern on one or more substrates.This substrate can for example be the glass utmost point of indium-Xi-oxide (ITO) coating.With the common slabstone typography ITO electrode is made wiring pattern.By the electric field that applies, the selection zone of one or two of liquid crystal layer can be addressed or read.This can simplify and/or the acceleration write/read operation.

A kind of with two optical storage mediums with liquid crystal layer of coding aligned twisted state (this is equivalent to numerical information), can be used as compact disk (CD) or compact disk read-only memory (CDROM).Optical storage medium is sandwiched between a pair of polarizer.By the optical system that focuses on and collect reading optical beam suitably each liquid crystal layer is carried out addressing or read.With reading the numerical information of having encoded by the light beam of each arrange regional and with suitable photodetector record transmitted light or intensity of reflected light.The strength information of having encoded is further handled as the function of the size of each layer, arrange regional position and transmitted light or intensity of reflected light.

A kind ofly have two optical storage mediums and can be used as repeatedly (WORM or CD-R) memory of Write once and read with two liquid crystal layers of the aligned twisted state capabilities of having encoded.Expose by the selection zone of the light alignment layer that will select with polarized light and to change the polarized light vector simultaneously and finish coding step.Described zone is equivalent to needed number information.As described to above-mentioned CD with aligned twisted state, this encoded digital information can be read repeatedly.

A kind ofly have two optical storage mediums with two liquid crystal layers of the aligned twisted state capabilities of encoding and can be used as and to wipe compact disk (CD-E).Ordered state in each zone is changed by the polarized light vector that change writes light beam, as described above, deposit fresh information then in, and can read this fresh information subsequently, as described above-mentioned CD with aligned twisted state.

Can be stored in photo image in the optical storage medium with two two liquid crystal layers that have the aligned twisted state of encoding.Without this image of polarizer is invisible.By suitable focusing with collect optical system and select to be read liquid crystal layer, and optical storage medium is put between a pair of polarizer, mode that can vision is read this photo.Can read positive or negative photographic image with the parallel to each other or vertical polarizer of a pair of its absorption axle.

A kind of optical storage medium that has the liquid crystal layer of two birefringence ordered states that have encode (this is equivalent to numerical information) can be used as compact disk (CD) or compact disk read-only memory (CDROM).Utilize suitable focusing and collect optical system, use the light beam of each arrange regional by selecting layer to read the encoded digital information of each liquid crystal layer, and measure transmitted light or catoptrical differing with the appropriate combination of polarizer and/or interferometer technique.Further handling as the function of the size of every layer position, arrange regional and transmitted light or catoptrical phase through the strength information of record.

A kind of optical storage mediums that have two liquid crystal layers with the birefringence ordered state ability of having encoded can be as Write once and read (WORM or CD-R) memory repeatedly.The exposure area is equivalent to needed number information.Encoded digital information can be read repeatedly, as above-mentioned to CD with birefringence ordered state described.

A kind of optical storage mediums that have two liquid crystal layers with the birefringence ordered state ability of having encoded can be as wiping compact disk (CD-E).Ordered state in each zone of selected layer can be changed by changing the above-mentioned polarized light direction vector that writes light beam.As described, can read this fresh information subsequently to CD with birefringence ordered state.

As mentioned above, photographic image can be stored in the optical storage medium that has two liquid crystal layers with the birefringence state of having encoded.Adopt the mode that the appropriate combination of polarizer and/or interferometer technique can vision to read this photo.Utilize the suitable arrangement of interferometer arrangement, can read positive or negative photographic image.

A kind ofly have two optical storage mediums and can be used as compact disk (CD) or compact disk read-only memory (CDROM) with liquid crystal layer of the compound ordered state (this is equivalent to numerical information) of having encoded.Utilize suitable focusing and collect optical system, light beam with each alignment area by selecting layer is read the numerical information of having encoded, and be used to relate to the appropriate combination of instrument technology, polarizer and photodetector, record transmitted light or catoptrical phase and/or intensity.The optical information that has write down is as the function of the position of each liquid crystal layer, arrange regional and transmitted light or intensity of reflected light size and be further processed.

A kind of optical storage mediums that have two liquid crystal layers with the compound ordered state ability of having encoded can be as Write once and read (WORM or CD-R) memory repeatedly.Write light beam with polarized light and can realize coding step with variable polarization light vector and described selection zone (this is equivalent to needed number information).The numerical information of having encoded as above-mentioned to CD with compound ordered state described, can read repeatedly.

A kind ofly have two optical storage mediums and can be used for to wipe compact disk (CD-E) with liquid crystal layer of the compound ordered state ability of having encoded.Select the ordered state in zone to change at each by the direction that change writes the polarized light vector of light beam.Store fresh information then, and as to CD with compound ordered state described that works is read out subsequently.

Photo image can be stored in and have in two optical storage mediums of liquid crystal layer with the compound ordered state of coding, adopts the mode that the suitable combination of collecting optical system, interferometer technique and polarizer can vision to read this photo.Utilize the appropriate combination of polarizer and/or interferometer technique can read positive or negative photo image.

A kind ofly have two optical storage mediums and can be used to store display with liquid crystal layer of aligned twisted state, birefringence ordered state or compound ordered state.Above-mentioned photographic image can make it to change into new image with writing light beam.In the case, when the change speed of image during greater than video speed, then this display can be used for film and TV.When being slower than the video pace of change, this light is stored display can be used for variable signal, for example is used to guide wagon flow.As mentioned above, a kind of interesting advantage of this optical storage medium is obtainable high visual angle, and this seldom sees in common LCD.

Have two or more optical storage mediums and can be used for this complex effect two-layer or multilayer with liquid crystal layer of aligned twisted state, birefringence ordered state or compound ordered state.Utilize suitable focusing and instrument light harvesting to learn system, two-layer complex effect can be read similarly with noted earlier.This optical storage medium can be used for signal Processing or information processing is used, for example light signal relevant (opticalsignal correlation), light logic operation, spatial filter (spatial filters) and photometry calculation.

The present invention describes with following embodiment, but these embodiment be illustrative and the intention that do not limit.

Embodiment 1

This embodiment explains the generation of dyestuff 3.

4-nitroaniline (5.6g) is dissolved in 12N hydrochloric acid (10.8ml) and the distilled water (7ml).Potpourri is chilled to is lower than 5 ℃, and add 2M sodium nitrite solution (22ml) gradually.Potpourri was stirred 1 hour, add urea (1.0g), stirred again 5 minutes.This solution is poured in second solution that wherein contains 5-methoxyl-2-aminotoluene (5.48g), sodium acetate (12.0g) and acetic acid (40ml).Under 5 ℃, stir this potpourri once in a while 1.5 hours, and got red solid after the filtration.With ethanol-tetrahydrofuran with this solid recrystallization secondary, 2-methyl-5-methoxyl-4-(4 '-nitrobenzophenone azo)-aniline.This thing (2.86g) is heated to 65 ℃ in ethanol (120ml).To stir 20 minutes in the adding of the NaHS (1.68g) in the water (20ml) and with potpourri.Add entry (60ml), and this potpourri cooling and filtration.The solid of collecting is got dyestuff 3 with ethyl alcohol recrystallization: fusing point 136-137 ℃, λ _Max=416 and 458nm, its ε value is respectively 38,200 and 28,600.

Embodiment 2

This embodiment explains the preparation of guest/main diazonium diamine (diazodiamine) 1/SPI-2000 polyimide light alignment layer (being appointed as S1).

Polyimide formulation SPI-2000 (0.5g) is mixed with diazonium diamine 1 (69.8mg) and N-N-methyl-2-2-pyrrolidone N-(9.9g).Stirred this potpourri 1 hour under the room temperature.This solution is directly filtered on the glass substrate surface of cleaning by 0.45 μ m Teflon filter membrane.The glass substrate that this has been applied rotates 1 minute to generate homogeneous film with the rotating speed of 2500RPM then.The film of gained was solidified 1 hour in 100 ℃ in nitrogen, solidified 2 hours in 195 ℃ subsequently.

Embodiment 3

This embodiment explains the preparation of the diazonium diamine 1 of covalent bond in the polyimide polymer alignment layer.

3,3 ', 4,4 '-benzophenone tetracarboxylic anhydride (40.25mg) mixes with the N-N-methyl-2-2-pyrrolidone N-(1.65g) of diazonium diamine 1 (46.75mg) and drying.With this potpourri in argon gas in stirring at room 18 hours.This poly-(amic acid) pre-polymer solution is diluted to 1 weight % solid with tetrahydrofuran (6.96g).This solution is directly filtered on the glass substrate surface of cleaning by 0.45 μ m teflon filter membrane.With this substrate that has applied with the rotating speed of 2500RPM rotation 1 minute to generate homogeneous film.The film of gained was solidified 15 minutes in 80 ℃ in nitrogen, subsequently 180 ℃ of heating 1 hour.The λ of this film _Max=376, the shoulder of the last one is arranged at the 472nm place.

Embodiment 4

This embodiment explains the covalent bonding 4 in the polyimide polymer alignment layer, 4 '-diamido Stilbene, 2, preparation.

With 3,3 ', 4,4 '-benzophenone tetracarboxylic dianhydride (40.25mg) and 4,4 '-diamido Stilbene, 2, (26.25mg) and dry N-methyl one pyrrolidone (1.26g) mix.This potpourri was at room temperature stirred in argon gas 18 hours.With tetrahydrofuran (5.32g) this poly-(amic acid) prepolymer is diluted to 1 weight % solid.This solution is directly filtered on the surface of the glass substrate that cleans by 0.45 μ m teflon filter membrane.With this substrate that has applied with the rotating speed spin coating of 2500RPM 1 minute to generate homogeneous film.The film of gained solidifies 15 minutes down subsequently 180 ℃ of heating 1 hour in 80 ℃ in nitrogen.The λ of film _Max=330nm.

Embodiment 5

This embodiment explains the preparation of monoazo diamine 3/ polyimide polymer of covalent bonding, to obtain light alignment layer (being appointed as S2).

3,3 ', 4,4 '-benzophenone tetracarboxylic dianhydride (40.25mg) is mixed with the N-N-methyl-2-2-pyrrolidone N-(1.37g) of monoazo diamine 3 (32.0mg) and drying.This potpourri was stirred 18 hours under room temperature in argon gas.With tetrahydrofuran (5.78g) this poly-(amic acid) pre-polymer solution is diluted to 1 weight % solid.This solution is directly filtered on the surface of the glass substrate that cleans by 0.45 μ m teflon filter membrane.With this substrate that has been coated with the rotating speed of 2500RPM rotation 1 minute to generate homogeneous film.The film of gained solidified 15 minutes down in 80 ℃ in nitrogen, subsequently 180 ℃ of heating 1 hour.The λ of this film _Max=387nm.

Embodiment 6

This embodiment explains polymerisable preparation to the body formulation of itemizing.

With methacrylate monomers Ia (114mg), and Ib (114mg) and dimethylacrylate IIa (60mg) and ethylene glycol dimethacrylate (9mg), ZLI-1982 (EM Chemicals, Hawthorne NY) nematic crystal 15mg, CB-15 Chinrally nematic alloy (15 μ g), quinhydrones inhibitor (9 μ g) and Irgacure 651 (originating from Ciba Giegy, Ardsley NY) light trigger (4mg) mix.This mixture heated to 85 ℃ and stirred 2 hours, be chilled to room temperature.Phase in the middle of room temperature generates nematic crystal: nematic-isotropy type changes=43.2 ℃.

Embodiment 7

Aligned twisted state in the liquid crystal layer of this embodiment explanation between two light alignment layer, the light alignment layer was exposed before box-packed joining.

With the pyrex substrate (2 " * 2 " * 1mm; Donnelly Corp., Holland Michigan) applies with guest/main diazonium diamine 1/SPI-2000 polyimide formulation of embodiment 2 and solidifies, and makes the light alignment layer.

Two substrates expose with polarized light subsequently, and this polarized light guides the background of liquid crystal to arrange when liquid crystal cell assembles.Fig. 6 has described the synoptic diagram of lighting device, and laser 6 is commercial argon lasers, and model is #2020-03 (Spectra-Physics, Piscataway, New Jersey), and it is 2.5 watts in the peak power that 514.5nm provides, by vertical polarization.Make laser beam pass through acousto-optic modulator 8, model is that (Intra-Action Corporation, Bellwood IL), use its modulating lasering beam to #AOM-40.Laser beam is reflected and leaves mirror 9 subsequently, by hole 10, and enter have condenser lens 11 (model #LK5100, General Scanning, Watertown, in twin shaft mirror system MA), this system is computer-controlled.Scanner makes and focuses on polarized laser beam and point on the light alignment layer 12, and comes flyback retrace across crossing this layer with this light beam, and stepping between the single pass line is about 15 microns after every.Laser beam is carried out switch by acousto-optic modulator 8, and this modulator 8 is by the circuit control of scanner.Enter that total laser power of coated substrates is 1.7 watts, and will focus on about 30 microns on laser beam coated substrates with scanner optics system.

After carrying out the exposure of carrying out for the background arrangement, a substrate that has applied is placed on the scanner focus, and the normal of substrate is rotated about 10 degree from its origin-location.The circle of a 1cm of scanning among 1/4th of coated substrates subsequently.Rotate 30 degree then second 1/4th of substrate shift-in, and from its reference position.At this second circle of scanning in 1/4th./ 4th of two remainders are repeated this operation, rotate 60 degree and 90 degree from the substrate reference position.

With liquid crystal cell of two substrate configuration that applied of having exposed.(55 μ m) is placed on the substrate that has applied with Mylar (mylar) bar, and another substrate then is placed on its top and clamps.The light alignment layer faces with each other, and the background orientation is parallel to each other.With clip substrate is pressed onto 55 microns spacing, epoxy resin is applied along the edge, and with 5 fens kinds of epoxy resin cure.Two spaces of box opposite side allow its blow-by.The blow-by opening of box is immersed in the ZLI-1982 nematic crystal (EM Industries, Inc, Hawthorne, New York), and be mixed with in this liquid crystal 0.02 weight %CB-15 chiral dopant (EM Industries, Inc.).This box is filled because of capillarity.After the filling, box is taken out from liquid crystal, cleaned, and use the epoxy sealing space.

How Fig. 7 explanation box when watching between the crossed-polarizer on the photograph light box presents.The background orientation appears axle along the polarizer of an input.The input polarization device makes light arrange the generation polarization along background.The output polarization device hinders optical transmission, because appearing of its axis of homology and input polarization device spool intersects.Consequently the background of box presents even black.

In the area of circle, a substrate that has exposed is once arranged along background, and exposure another substrate repeatedly is then with 10,30, and 60 and 90 degree (angle of substrate rotation when this is equivalent to the circle exposure) are arranged.This causes liquid crystal to arrange (being respectively 13,14 among Fig. 7,15 and 16) with the twisted-nematic that the twist angle that equals 10,30,60 and 90 degree carries out.The twisted-nematic state causes one of polarization polarisation of light vector rotation and twist angle angle same.Subsequently, the circle of 10,30,60 and 90 degree transmissions with respect to the transmission of background brighten gradually (with hatched density among Fig. 7 gradually step-down represent).90 degree circles are the brightest.Therefore, observe the gray scale of 4 levels with respect to background.

Embodiment 8

This embodiment explanation has greater than 16 and is less than or equal to the high-resolution two dimension photographic image of 256 ordered states.After the box assembling and pouring into liquid crystal, in liquid crystal layer, set up the aligned twisted state.An alignment layer be the polyimide that common machinery nuzzles up, and another is the light alignment layer.

To be coated in substrate (2 " * 2 " * 1mm) diazonium diamine 1/SPI-2000 polyimide (SI) carries out the light background to be arranged, shown in embodiment 7.Another kind of like SPI-2000 polyimide solution in the substrate spin coating in its surface.The substrate that scribbles SPI-2000 is solidified in stove.By a side non-directional that substrate has been applied rubbed fiber cloth and the background of mechanically introducing the SPI-2000 coated substrates is arranged.The box of one 55 μ m of system shown in embodiment 7, its light alignment layer and SPI-2000 mechanical arrangement layer generate the arrangement that is parallel to each other toward each other.Fill this box with identical liquid crystal compound, as described in embodiment 7.When between polarizer, observing, see that liquid crystal is arranged in parallel equably.

The box that assembles is placed in the optical exposure device of Fig. 8.Box is fixed on two motor transmission platforms, so that this box moves in X-Z plane (in Fig. 8 with double-headed arrow and put 22 expressions), and this plane is positioned at the focus place of 15cm focal length lenses 20.The substrate that has light alignment layer 12 is fixed near 15cm focal length lenses 20 parts.The substrate of polyimide layer 21 that is coated with mechanical system ejection is only insensitive to incident polarization.With suitable orientation and 1/4th plates 19 electrooptic modulator 18 (Conoptics of Danbury linked together, CT) function as executing voltage changes from Innova 400 argon lasers 17 (Coherent, Inc., of Santa Clara, the output linear polarization state of 514.5nm light CA).When the voltage on modulator driver was transferred to 1 volt by 0 volt, linear polarization state forwarded-45 degree to by 45 jiaos in the X-Z plane of box.Modulator and transmission platform are by computer control.

In order to write high resolving power in box, the digital video photographic image with people of 702 * 738 of 256 grades of gray scales is used to measure incident polarization at the incident polarization angle of being fixed in the box on the experimental provision by computing machine.Consider that final box will go to observe from polarizer, the corrected value of voltage is calculated by the grey level of image.For 0 grade of gray scale in the image, the relevant voltage of modulator is 0 volt.Corresponding to this voltage, the polarization state that is incident on this box is 45 degree on substrate plane.Therefore, the twist angle of gained is-45 degree, and this makes and produce row's phase state of deceiving when watching between the axis of homology is the polarizers of 45 degree each other.

Each video in image, 13 milliseconds corresponding box exposure takes place in each video gray-scale value in suitable polarization angle.This box moves along the speed of X-axis with about 3mm/ second, this cause on the box in 13 milliseconds about 38 μ m alignment areas be exposed.After all the 702 times exposures of a given row of image had been carried out, this box moved 38 μ m along the Z axle, and the exposure next line.This step repeats 738 times given image along the Z axle.The total exposure district of this box is about 1 " * 1 ".

Because diazonium diamines 1/SPI-2000 polyimide alignment layer is only arranged to the incident light sensitivity, the liquid crystal of layer contact is polarized the light rotation therewith, and keeps the influence that is not subjected to incident light with the contacted liquid crystal of polyimide alignment layer of mechanical registeration.This causes about 38 μ m * 38 μ m alignment area that exposed to have the aligned twisted state, and its twist angle depends on the gray scale of the initial number video in the computer picture.

After the exposure, when (do not have polarizer) when watching in nonpolarized light, this box does not show arrange regional or this visual optical signal.Yet, when this exposure box in each other in the polarizers of 45 degree when observing, can see that a people's positive (this image in box is corresponding to computer picture) is high-resolution (1 " * 1 " 702 * 738 arrange regionals are arranged in the zone) image.Rotate to-45 degree by the output polarization device is spent from 90 with respect to the position of input polarization device, can see negative (image in the box has the bright and dark space opposite with original image in the computing machine) high-resolution portrait.This image looked and is equal to initial computer picture when naked eyes were judged.Compare with common LCD, this image has wide visual angle.

Embodiment 9

This embodiment explanation between two aligned twisted states between the alignment layer of not sharing the same light to the sensitivity of different wave length.After the assembled and filling, only, generate arrange regional at box with aligned twisted state with a light alignment layer exposure.Use the perfluorinate liquid crystal layer in this embodiment.

With diazonium diamine 1/SPI-2000 polyimide be spin-coated on glass substrate (0.9 " * 1.2 " * 1mm), generate S1 light alignment layer.Be spin-coated on second similar substrate with monoazo diamine 3/ polyimide polymer, generate S2 light alignment layer.This two coating all is cured in stove subsequently.

As shown in Figure 7, the substrate with the S1 coating carries out the background arrangement.With the device of representative illustrated in Figure 9 the substrate of S2 coating being carried out background arranges.Substrate 24 with the S2 coating in this experiment is fixed on 2 XZ transfer tables (double-headed arrow 25 with Fig. 9 marks), and a side that makes coating is towards incoming laser beam.Is the ultraviolet laser of 333～364mm with 17 rotations of Innova 400 laser instruments to produce wavelength.The cylindric lens 23 of 5cm focal length are focused into line (1cm * 200 μ m) to incident 1cm light beam on the substrate 24 of S2 coating.Be coated with substrate along the Z direction with the constant speed transmission, then in the directions X stepping.Repeat this operation till coated substrates is exposed fully.

Arrange substrate with two embodiment, 7 described backgrounds and make a box, pour into MIC-6043-000 (EM Industries, Inc., Hawthorne, New York) then.When watching in two polarizers, this box presents even, parallel background and arranges.

Subsequently this box is exposed in embodiment 7 and the described scanister of Fig. 6.The circle of diameter 1mm is withered to be exposed with respect to being added to the different orientation that is sitting at scanner system 11 half-wave plate before.The polarization of incident light state is rotated with the twice of the half-wave plate anglec of rotation.Therefore, can obtain to be controlled at the straightforward procedure of light polarization orientation in the plane of box by the rotation half-wave plate.The substrate of the S1 of box coating is to 514.5nm used in the scanister only responsive.Therefore, this substrate is near incoming beam.Four circles are exposed because of half- wave plate rotation 5,15,30 and miter angle, and these four angles are changed to 10,30,60 and 90 degree corresponding to the polarization angle in S1 coated substrates plane.

Box is turned to, and like this, polarisation of light is arranged perpendicular to background before rotating half-wave plate.Because the substrate of S1 coating is to the light activated only substrate of 514.5nm, thus liquid crystal display be equivalent to twist angle 10,30 at each, the aligned twisted state in the 1mm circle of 60 and 90 degree.

Embodiment 10

This embodiment explanation has two liquid crystal layers of aligned twisted state.In addition,, after assembling of multilayer pond and filling, be polarized the light exposure, be created on the arrange regional that has different aligned twisted states in each liquid crystal layer in the light alignment layer of each alignment layer centering.

With the diazonium diamine 1/SPI-2000 polyimide among the embodiment 9 with two substrates (0.9 * 1.2 " * 1mm) carry out spin coating.(Brewer Science, Rolla MO) apply and are called S3 with Nissan SE-7311 polyimide solution for the 3rd substrate.These substrates solidify in stove.The substrate of S3 coating is applied with Nissan SE7311 polyimide in the opposite side of substrate that it scribbles the 1st S3 layer again.Subsequently it is solidified in stove.

Making the S1 coated substrates carry out background with embodiment 7 described beam scanner systems arranges.With embodiment 8 described mechanical polishing technology background all being carried out with each side of the substrate of S3 coating in both sides arranges.

By following assembling multilayer box.Mylar (mylar) packing ring (55 μ m) is placed on the substrate of S1 coating, bilateral S3 coated substrates is placed on the Mylar packing ring, again the Mylar packing ring is placed on the opposite side of bilateral S3 coated substrates, then second S1 coated substrates is placed on the top of second group of Mylar packing ring.These three substrates are clipped together, and seal with the epoxy resin among the embodiment 7.Among two box seams of MLC6043-000 liquid crystal kapillary filling simultaneously.Then the multilayer box is cleaned, and grout is sealed with epoxy resin.When watching in two polarizers, two liquid crystal layers in the multilayer box all present even, parallel background and arrange.

The multilayer box is fixed on the scanner device as embodiment 9, and a S1 coated substrates is right after incoming laser beam.As described in embodiment 9, four 1mm circles are exposed, generate aligned twisted state with four twist angles at first liquid crystal layer.Use second S1 coated substrates flicking multilayer box subsequently, and repeat four 1mm exposures near incoming laser beam.This produces four twist angles at second liquid crystal layer.In order to be easier to watch and analyze multilayer box, care should be used to prevent the overlapping of in each liquid crystal layer arrange regional.When watching the multilayer box in two polarizers, observe four other gray scales of level at each liquid crystal layer.

Embodiment 11

This embodiment explanation has two liquid crystal layers of aligned twisted state.Each liquid crystal layer is subjected to the light alignment layer of different wave length sensitivity is controlled.In addition, after assembling of multilayer box and filling, expose with different wave length in the light alignment layer of each alignment layer centering, to be formed on the zone that has the aligned twisted state in each liquid crystal layer.

As embodiment 10 assembling multilayer boxes, different is that the substrate that a S1 applies is replaced by a S2 coated substrates that derives from embodiment 9.Intermediate plate is still a bilateral and is removed multiple substrate by S3, and its both sides are by mechanical polishing.Before assembling, S1 is that apply to carry out the background arrangement as embodiment 10 and embodiment 9 respectively with the substrate S2 coating.

Subsequently, the S1 of multilayer box being applied a side exposes as embodiment 10 with 4 1mm circles.One of the S2 of multilayer box coating is sidelong near incident beam place in the embodiment 9 ultraviolet devices.The aluminium sheet that the 1mm aperture is wherein arranged is placed on the top of box as mask.Box is fixed, its background is arranged perpendicular to polarization of incident light.For ease of observing, be careful to guarantee in the exposure area of S2 side not with overlapping at those of the S1 side of many folded boxes.A little boxes are pressed the normal rotation 10 of substrate and spent, as embodiment 9, under focused beam acts, transmit subsequently by the X-Z transfer station.Mask prevents except the 1mm aperture the local luminous of other.Diverse location at box repeats this process, rotation 30,60 and 90 degree.When between two polarizers, watching the multilayer box, in each liquid crystal layer, observe 4 other gray scales of level.

Embodiment 12

This embodiment explanation has two liquid crystal layers of aligned twisted state.These two alignment layer are to comprising two-layer light alignment layer to the different wave length sensitivity.In addition, after assembling of multilayer box and filling, only there is a light alignment layer to be exposed in the polarized light in each alignment layer, has the zone of aligned twisted state with generation.

As embodiment 10 assembling multilayer boxes, the substrate of the S3 coating of both sides that different is is glued to the substrate of two 0.9 " * 1.2 " S2 coatings together and is replaced.Carry out as the S2 coated substrates among the embodiment 9 after background arranges before box assembling and with two, the substrate of S2 coating on two is glued to together, the side that S2 applies outwardly.(Norland, New Brunswick NJ) is glued to substrate together with Norland 60 Photocurable adhesives.With unpolarized low-power black light with glue curing.This causes the substrate of the S2 coating of bilateral, and its thickness is 2mm, and it is constituted the multilayer box with the substrate that two S1 apply.

As embodiment 10 each side of multilayer box is exposed.When between two polarizers, watching this multilayer box, in each liquid crystal layer, observe 4 other gray scales of level.

Embodiment 13

The birefringence ordered state of this embodiment explanation in the liquid crystal layer between two light alignment layer.

Repeat embodiment 7, different is after their backgrounds are arranged, and the circle of using the 1cm diameter is in per quart, and the substrate that two S1 are applied exposes.Because these two S1 coated substrates will face with each other, each circle in the substrate of second S1 coating must be complementary with the suitable circle in the substrate of first S1 coating, is not distorted in liquid crystal guaranteeing.Therefore, arrange regional will have its birefringence axis, arrange rotation one fixed numbers with axle with respect to background.Consequently, on first substrate, carry out 10 degree rotations and carried out the circle that exposes, must be complementary with the circle that on second substrate, has carried out exposure with negative 10 degree rotations with plate.Each each rotation angle of 1/4th (promptly 30 and-30 spend, 60 and-60 degree, 80 and-80 degree), all repeat this step.The situation of 90 degree is degeneracies, when watching between two polarizers, can present and the background similar.

Join box-packed as embodiment 7, the suitable circle of being careful each substrate carries out overlapping.With the ZLI-1982 that does not contain chiral dopant box is carried out the kapillary filling.When watching the box of making between polarizer, the circle of 10 and 80 degree has the gray scale of same levels.30 with 60 the degree fenestras be identical.Yet 10 and 30 (and therefore to 80 and 60) have the gray scale of different stage.Therefore, concerning these four circles, only observe two grey levels, this is because when the birefringence ordered state, and per 45 degree of grey level promptly repeat.

Embodiment 14

The compound ordered state of this embodiment explanation in the liquid crystal layer between two light alignment layer.Therefore, single arrange regional can have the birefringence axis that rotates in alignment layer, also has the distortion from an alignment layer to another alignment layer.

Repeat embodiment 13, different is, equals-20,0 four rotation angle, in 90 and-30 1/4th, second S1 light alignment layer is exposed with polarized light.The circle of 10,30,60 and 80 degree of care should be used on first S1 coated substrates is overlapping with the circles that reach-30 degree at second on-chip-20,0,90 respectively.The Manufactured box of ZLI-982 kapillary filling with the %CB-15 that contains 0.02 weight.Between two polarizers, watch the box of making.Can be observed four other gray scales of level.

Embodiment 15

This embodiment explanation has the polyreaction of the liquid crystal layer of aligned twisted state, generates to have the fixedly polymer film of aligned twisted state.

Box as the S1 light alignment layer that comprises two pre-exposure of manufacturing as described in the embodiment 7.In the dark in 85 ℃ with as embodiment 6 described polymerizable monomer composition with the box filling.At room temperature allow this box anneal 2 hours.Use ultraviolet light (200WHg arc) with this box exposure 30 seconds then, and immerse in 15 ℃ of water 1/2 inch simultaneously.Described similar with embodiment 7, the gray scale of four levels intactly and be fixed in the polymeric membrane.

Claims (51)

1. optical storage medium with gray scale ability, it comprises

A plurality of end face substrates that bunchiness is arranged with one or more pairs of end faces;

It is right to form alignment layer to last alignment layer to be placed on this end face, and wherein at least one alignment layer that each described alignment layer is right is the light alignment layer, and light alignment layer wherein comprises anisotropic absorption molecule or component,

Be placed on this alignment layer between liquid crystal layer,

Wherein each liquid crystal layer comprises three or more arrange regional with three or more different ordered states, and

Wherein different ordered states is subjected to the control of the exposure of described smooth alignment layer, and the wavelength that uses during exposure is the absorption band of anisotropic absorption molecule or component or the polarized light within it.

2. optical storage medium according to claim 1, wherein each described liquid crystal layer comprises four or a plurality of arrange regional that has between 4～2000 different ordered states.

3. optical storage medium according to claim 1, wherein this ordered state is the ordered state of distortion.

4. optical storage medium according to claim 1, wherein this ordered state is the birefringence ordered state.

5. optical storage medium according to claim 1, wherein this ordered state is compound ordered state.

6. the optical storage medium according to claim 1 wherein has two end group sheets and a liquid crystal layer.

7. the optical storage medium according to claim 1 wherein has three end group sheets and two liquid crystal layers.

8. the optical storage medium according to claim 1 wherein has between 4～21 end group sheets with between 3～20 liquid crystal layers.

9. optical storage medium according to claim 1, wherein said anisotropic absorption molecule or component are having absorption maximum between 150nm～1600nm.

10. optical storage medium according to claim 1, wherein said anisotropic absorption molecule or component are having absorption maximum between 150nm～800nm.

11. the optical storage medium according to claim 1, wherein said anisotropic absorption molecule or component are having absorption maximum between 150nm～400nm.

12. the optical storage medium according to claim 1, wherein said anisotropic absorption molecule or component are having absorption maximum between 400nm～800nm.

13. the optical storage medium according to claim 1, the size of wherein said arrange regional are 0.1～100 μ m ²

14. the optical storage medium according to claim 1, wherein said liquid crystal layer is a polymerisable liquid crystal.

15. optical storage medium according to claim 14, wherein this polymerizable nematic crystal is a polymerizable nematic composition, at least a general formula (I) monomer that comprises (A) 20～80 weight %, n is 10 in the formula, 12 or 14, reach (B) monomer of at least a general formula (I) of 80～20 weight %, n is 4 in the formula, 6, or 8;

R is CH in the formula ₃Or H, and Y be covalent bond or-CO ₂-.

16. the optical storage medium according to claim 15, wherein this polymerizable nematic composition also comprises difunctionality methacrylate or the acrylate monomer (II) of 0.1～30 weight %:

R is CH in the formula ₃Or H, R ₁Be CH ₃, H, Cl ,-OCH ₃, and p=1-12.

17. the optical storage medium according to claim 14, wherein polymerisable liquid crystal be exposed under the photochemical radiation to form polymer substrate.

18. the optical storage medium according to claim 1, wherein said liquid crystal layer is a nematic crystal.

19. the optical storage medium according to claim 18, wherein this nematic crystal is selected from by 4-cyano group-4 '-alkyl biphenyl and group that the 4-alkyl-(4 '-cyano-phenyl) cyclohexane is formed.

20. the optical storage medium according to claim 1, wherein said liquid crystal layer are guest-main potpourris.

21. optical storage medium according to claim 20, wherein said guest-main potpourri comprises dichromatism aromatics azo, two (aromatics azo), three (aromatics azos), four (aromatics azos), five (aromatics azos), anthraquinone, part cyanine (mericyanine), methine, 2-phenylazothiazole, 2-phenylazobenzene a pair of horses going side by side thiazole, Stilbene, 1, two (2-phenyl vinyl) benzene, 4 of 4-, 4 '-two (aromatics azo) Stilbene, perylenes, and 4, the 8-diaminostilbene, 5 naphthoquinone dyestuffs.

22. the optical storage medium according to claim 21, wherein said guest-main potpourri comprise aromatics azo, many (aromatics azos) and Stilbene dyestuff.

23. the optical storage medium according to claim 20, wherein said guest-main potpourri comprises nematic crystal.

24. the optical storage medium according to claim 23, wherein said nematic crystal are selected from by 4-cyano group-4 '-alkyl biphenyl and group that the 4-alkyl-(4 '-cyano-phenyl) cyclohexane is formed.

25. optical storage medium according to claim 1, wherein said anisotropic absorption molecule or component are aromatics azo, two (aromatics azo), three (aromatics azos), four (aromatics azos), five (aromatics azos), anthraquinone, part cyanine (mericyanine), methine, 2-phenylazothiazole, 2-phenylazobenzene a pair of horses going side by side thiazole, Stilbene, 1, two (2-phenyl vinyl) benzene, 4 of 4-, 4 '-two (aromatics azo) Stilbene, perylenes, and 4, the 8-diaminostilbene, 5 naphthoquinone dyestuffs.

26. the optical storage medium according to claim 25, wherein said anisotropic absorption molecule or component are aromatics azo, many (aromatics azos) and Stilbene dichroic dye.

27. the optical storage medium according to claim 26, wherein the anisotropic absorption molecule is selected from by diazonium diamine 1,4,4 ' one diamino-stilbene and monoazo diamine 3.

28. the optical storage medium according to claim 1, wherein said smooth alignment layer comprises polyimide polymer.

29. the optical storage medium according to claim 28, wherein said anisotropic absorption molecule or the component nonbonding solute in the polyimide polymerization.

30. the optical storage medium according to claim 28, wherein said anisotropic absorption molecule or component are covalently bound on this polyimide polymer.

31. the optical storage medium according to claim 1, the two or more of wherein said smooth alignment layer are having absorption maximum between 150nm～1600nm, and difference is greater than 10nm.

32. the optical storage medium according to claim 31, wherein said absorption maximum differs by more than 50nm.

33. the optical storage medium according to claim 1, the two or more of wherein said smooth alignment layer are having an absorption maximum between 150 to 800nm, and differ by more than 10nm.

34. the optical storage medium according to claim 33, wherein said absorption maximum differs by more than 50nm.

35. the optical storage medium according to claim 1, wherein said smooth alignment layer two or more in that an absorption maximum is arranged between 150 to 400nm differ by more than 10nm.

36. the optical storage medium according to claim 35, wherein said absorption maximum differs by more than 50nm.

37. the optical storage medium according to claim 1, wherein said smooth alignment layer is having an absorption maximum between 400 to 800nm, and differs by more than 10nm.

38. the optical storage medium according to claim 37, wherein said absorption maximum differs by more than 50nm.

39. the optical storage medium according to claim 1, wherein said ordered state is the mixing that is selected from the state of being made up of distortion, birefringence and compound alignment.

40. the optical storage medium according to claim 1 further comprises:

A kind of device that described substrate is separated, and

A kind of device of described substrate sealing being made box.

41. the optical storage medium according to claim 1, it is the compact disk with read-only ability.

42. the optical storage medium according to claim 17, it is the compact disk with read-only ability.

43. the optical storage medium according to claim 1, it is to have the repeatedly compact disk of ability of Write once and read.

44. the optical storage medium according to claim 1, it is to have to write/the wiped compact disk of write capability again.

45. the optical storage medium according to claim 20, it is to have to write/the wiped compact disk of write capability again.

46. the optical storage medium according to claim 1, it stores photographic image.

47. the optical storage medium according to claim 46, it has wide visual angle.

48. the optical storage medium according to claim 46, wherein this photographic image can be read with positive image or negative image.

49. the optical storage medium according to claim 1 or 20, it is that light is stored display.

50. the optical storage medium according to claim 49, wherein said light are stored display and are had wide visual angle.

51. the optical storage medium according to claim 1, wherein said substrate has the electrode of making wiring pattern on one of one or more pairs of end faces or two upper surfaces.

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