# US 6,721,257 B2 · Multilayer recordable optical medium with fluorescent reading

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- Number: US 6,721,257 B2
- Document ID: US6721257B2
- Status: Granted
- Kind: B2
- Application number: 09/872,014
- Filed: 2001-06-04
- Published: 2002-07-25
- Granted: 2004-04-13
- Earliest claimed: 2000-06-02
- Inventors: Mark Alperovich; Eugene Kapinus; Irene Zuhl; Jacob Malkin; Eugene Levich; Vladimir Schwartz
- Web page: https://patentgrep.com/patent/US6721257B2

## CPC

- G11B 7/249: containing organometallic compounds (G11B7/246 takes precedence)
- G11B 7/00455: {involving reflectivity, absorption or colour changes}
- G11B 7/005: Reproducing (G11B7/0065 takes precedence)
- G11B 7/24: Record carriers characterised by shape, structure or physical properties, or by the selection of the material (characterised by the arrangement of information on the carrier G11B7/007)
- G11B 7/24038: Multiple laminated recording layers
- G11B 7/242: of recording layers
- G11B 7/244: comprising organic materials only
- G11B 7/245: containing a polymeric component
- G11B 7/246: containing dyes
- G11B 7/247: methine or polymethine dyes
- G11B 7/248: porphines; azaporphines, e.g. phthalocyanines
- G11B 7/2533: comprising resins
- G11B 7/2538: polycycloolefins [PCO]
- G11B 2007/24624: {fluorescent dyes}
- G11B: INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER (recording measured values in a way that does not require playback through a transducer G01D9/00; recording or playback apparatus using mechanically marked tape, e.g. punched paper tape, or using unit records, e.g. punched or magnetically marked cards G06K; transferring data from one type of record carrier to another G06K1/18; circuits for coupling output of reproducer to radio receiver H04B1/20; gramophone pick-ups or like acoustic electromechanical transducers or circuits therefor H04R)

## Abstract

In a multilayer recordable optical medium, each recording layer includes a luminophore that fluoresces under reading laser light and a quencher capable of quenching the luminophore fluorescence. Initially, the luminophore and the quencher are not intermixed, so that the default state of the luminophore is fluorescent. During writing, focused writing radiation heats a spot in the medium so as to cause the luminophore and the quencher to be intermixed, thereby quenching the fluorescence.

## Claims

### Claim 1

A multilayer recordable optical medium for writing by writing light and fluorescent reading by reading light, the reading light causing a generation of fluorescent light, the medium comprising a plurality of recordable medium layers layers, each recordable medium layer comprising:
a substrate that is transparent to the writing light, the reading light, and the fluorescent light; and
an active layer applied onto the substrate;
wherein the active layer comprises:
a fluorescing phase comprising at least one luminophore capable of absorbing the reading light and emitting the fluorescent light; and
a quenching phase comprising at least one substance capable of quenching a fluorescence of the at least one luminophore.

### Claim 2 (depends on 1)

The medium of claim 1, wherein the reading light and the writing light have a common wavelength.

### Claim 3 (depends on 1)

The medium of claim 1, wherein the reading light and the writing light have different wavelengths.

### Claim 4 (depends on 1)

The medium of claim 1, wherein the fluorescing and quenching phases constitute polymer thermoplastic layers in immediate contact with each other.

### Claim 5 (depends on 1)

The medium of claim 1, wherein fluorescing phase comprises two polymer thermoplastic semilayers, between which the quenching phase is provided as a polymer thermoplastic layer.

### Claim 6 (depends on 1)

The medium of claim 1, wherein the quenching phase comprises two polymer thermoplastic semilayers, between which fluorescing phase is provided as a polymer thermoplastic layer.

### Claim 7 (depends on 1)

The medium of claim 1, wherein the fluorescing phase comprises a polymer thermoplastic layer, and the quenching phase comprises a binder-free quenching transparent layer.

### Claim 8 (depends on 1)

The medium of claim 1, wherein the fluorescing phase comprises two polymer thermoplastic semilayers, between which the quenching phase is provided as a binder-free quenching transparent layer.

### Claim 9 (depends on 1)

The medium of claim 1, wherein the active layer further comprises a spacing layer between the fluorescing and quenching phases.

### Claim 10 (depends on 1)

The medium of claim 1, wherein the fluorescing phase comprises a polymer thermoplastic layer and a grained sorbent dispersed in the polymer thermoplastic layer with the at least one luminophore adsorbed on a surface of the sorbent.

### Claim 11 (depends on 10)

The medium of claim 10, wherein the sorbent is selected from the group consisting of Areosil, titanium dioxide, aluminosilicates, and titanosilicates.

### Claim 12 (depends on 1)

The medium of claim 1, wherein the quenching phase comprises a polymer thermoplastic layer and a grained sorbent dispersed in the polymer thermoplastic layer with the at least one quencher adsorbed on a surface of the sorbent.

### Claim 13 (depends on 12)

The medium of claim 12, wherein the sorbent is selected from the group consisting of Areosil, titanium dioxide, aluminosilicates, and titanosilicates.

### Claim 14 (depends on 1)

The medium of claim 1, wherein the active layer comprises a polymer layer of the fluorescing phase in which the quenching phase is dispersed.

### Claim 15 (depends on 14)

The medium of claim 14, wherein the quenching phase comprises particles of a solid quencher.

### Claim 16 (depends on 15)

The medium of claim 15, wherein the particles of the solid quencher are enclosed in a polymer binder.

### Claim 17 (depends on 14)

The medium of claim 14, wherein the quenching phase comprises a dispersed sorbent with the at least one quencher adsorbed on a surface of the sorbent.

### Claim 18 (depends on 17)

The medium of claim 17, wherein the sorbent is selected from the group consisting of Areosil, titanium dioxide, aluminosilicates, and titanosilicates.

### Claim 19 (depends on 1)

The medium of claim 1, wherein the active layer comprises a polymer layer of the quencher in which the fluorescing phase is dispersed.

### Claim 20 (depends on 19)

The medium of claim 19, wherein the fluorescing phase dispersion comprises particles of a solid luminophore.

### Claim 21 (depends on 20)

The medium of claim 20, wherein the particles of the solid luminophore are enclosed in a polymer binder.

### Claim 22 (depends on 19)

The medium of claim 19, wherein the fluorescing phase comprises a dispersed sorbent with the at least one luminophore adsorbed on a surface of the sorbent.

### Claim 23 (depends on 22)

The medium of claim 22, wherein the sorbent is selected from the group consisting of Areosil, titanium dioxide, aluminosilicates, and titanosilicates.

### Claim 24 (depends on 1)

The medium of claim 1, wherein the active layer comprises a polymer thermoplastic layer in which dispersions of the fluorescing and quenching phases are distributed.

### Claim 25 (depends on 1)

The medium of claim 1, wherein the at least one luminophore does not absorb the writing light.

### Claim 26 (depends on 1)

The medium of claim 1, wherein the at least one luminophore absorbs the writing light.

### Claim 27 (depends on 1)

The medium of claim 1, wherein the at least one quencher absorbs the writing light.

### Claim 28 (depends on 1)

The medium of claim 1, wherein the at least one quencher absorbs the fluorescent light.

### Claim 29 (depends on 1)

The medium of claim 1, wherein the at least one quencher does not absorb the fluorescent light.

### Claim 30 (depends on 1)

The medium of claim 1, wherein the fluorescing phase comprises a non-fluorescing dye capable of absorbing the writing light and converting the absorbed writing light to heat.

### Claim 31 (depends on 30)

The medium of claim 30, wherein the non-fluorescing dye does not absorb the reading light or the fluorescing light.

### Claim 32 (depends on 31)

The medium of claim 31, wherein the non-fluorescing dye is selected from the group consisting of phthalocyanine, naphthalocyanine, complex metal, radical, coumarin, xanthene, quinone, azo, polymethyne, acrydine, quinoneimide, azine, diphenylmethane, indigoid, thioindigoid, and triphenylmethane.

### Claim 33 (depends on 30)

The medium of claim 30, wherein the non-fluorescing dye is selected from the group consisting of phthalocyanine, naphthalocyanine, complex metal, radical, coumarin, xanthene, quinone, azo, polymethyne, acrydine, quinoneimide, azine, diphenylmethane, indigoid, thioindigoid, and triphenylmethane.

### Claim 34 (depends on 1)

The medium of claim 1, wherein the quenching phase comprises a non-fluorescing dye capable of absorbing the writing light and converting the absorbed writing light to heat.

### Claim 35 (depends on 34)

The medium of claim 34, wherein the non-fluorescing dye does not absorb the reading light or the fluorescing light.

### Claim 36 (depends on 35)

The medium of claim 35, wherein the spacing layers comprise a material selected from the group consisting of UV-solidified lens cements and thermoplastic materials gluing when heated under pressure.

### Claim 37 (depends on 35)

The medium of claim 35, wherein the non-fluorescing dye is selected from the group consisting of phthalocyanine, naphthalocyanine, complex metal, radical, coumarin, xanthene, quinone, azo, polymethyne, acrydine, quinoneimide, azine, diphenylmethane, indigoid, thioindigoid, and triphenylmethane.

### Claim 38 (depends on 35)

The medium of claim 35, wherein the non-fluorescing dye is selected from the group consisting of phthalocyanine, naphthalocyanine, complex metal, radical, coumarin, xanthene, quinone, azo, polymethyne, acrydine, quinoneimide, azine, diphenylmethane, indigoid, thioindigoid, and triphenylmethane.

### Claim 39 (depends on 1)

The medium of claim 1, wherein the fluorescing phase comprises two luminophores with an absorption spectral range of one of the two luminophores overlapping with a fluorescence spectral range of the other of the two luminophores.

### Claim 40 (depends on 1)

The medium of claim 1, wherein the at least one luminophore is selected from the group consisting of compounds related to polycyclic condensed aromatic hydrocarbons and derivatives thereof, hydrocarbons containing arylethylene and arylacetylene moieties and derivatives thereof, coumarin, xanthene, acridine, oxazine, azine, perylene, terylene, violanthrone, cyanine, phthalocyanine, indigoid, thioindigoid, complex metal dyes and porphyrins.

### Claim 41 (depends on 40)

The medium of claim 40, wherein the quencher is selected from thr group consisting of compounds based on aromatic hydrocarbons and their derivatives, phthalocyanine, naphthalocyanine, complex metal, radical, coumarin, xanthene, quinone, azo, polymethyne, acridine, quinoneimide, azine, diphenylmethane, indigoid, thioindigoid, and triphenylmethane.

### Claim 42 (depends on 1)

The medium of claim 1, wherein the substrate is formed from a material selected from the group consisting of polycarbonate, polycycloolefin, polymethylacrylate, polymethylmetacrylate and polystyrene films.

### Claim 43 (depends on 1)

The medium of claim 1, wherein the substrate comprises a polymer selected from the group consisting of polymethylacrylate, polyvinyl chloride, chlorinated polyvinyl chloride, acrylate and epoxy photopolymerized plastics.

### Claim 44 (depends on 1)

The medium of claim 1, wherein each of the fluorescing and quenching phases comprises a resin selected from the group consisting of acrylic and vinyl polymers, alkyd, coumarone-indene, epoxy and phenolic resins, fluoropolymers, aminoplasts, polyacetals, polyacrylics, polyalkylenes, polyalkenylenes, polyalkynylenes, polyamic acids, polyamides, polyanhydrides, polyarylenealkenylenes, polyarylenealkylenes, polyarylenes, polyazomethynes, polybenzimidazoles, polybenzothiazoles, polybenzoxazinones, polybenzoxazoles, polybenzyls, polycarbodiimides, polycarbonates, polycarboranes, polycarbosilanes, polycyaurates, polydienes, polyester-polyuretanes, polyesters, polyetheretherketones, polyether-polyuretanes, polyethers, polyhydrazides, polyimidazoles, polyimides, polyimines, polyisocyanurates, polyketones, polyolefins, polyoxadiazoles, polyoxides, polyoxyalkylenes, polyoxyarylenes, polyoxymethylenes, polyoxyphenylenes, polyoxyphenyls, polyphosphazenes, polyquinolines, polyquinoxalines, polysilanes, polysilazanes, polysiloxazanes, polysilsesquioxanes, polysulfonamides, polysulfones, polythiazoles, polythioalkylenes, polythioarylenes, polythioethers, polythiomethylenes, polyureas, polyurethanes, polyvinyl acetals, polyvinyl butyrals and polyvinyl formals.

### Claim 45 (depends on 1)

The medium of claim 1, wherein each of the fluorescing and quenching phases comprises a plasticizer.

### Claim 46 (depends on 1)

The medium of claim 1, wherein, in each of the fluorescing and quenching phases, the plasticizer is selected from the group consisting of alkyl phthalates, phosphates, adipates and sebacates, polyethers, and epoxides.

### Claim 47 (depends on 1)

The medium of claim 1, comprising from two to twenty of the recordable medium layers.

### Claim 48 (depends on 47)

The medium of claim 47, wherein the recordable medium layers alternate with spacing layers.

### Claim 49 (depends on 1)

The medium of claim 1, wherein the medium is formed as a disc.

### Claim 50 (depends on 1)

The medium of claim 1, wherein the medium is formed as a card.

### Claim 51

A method of recording information, the method comprising:
(a) providing a multilayer recordable optical medium for writing by writing light and fluorescent reading by reading light, the reading light causing a generation of fluorescent light, the medium comprising a plurality of recordable medium layers layers, each recordable medium layer comprising:
a substrate that is transparent to the writing light, the reading light, and the fluorescent light; and
an active layer applied onto the substrate;
wherein the active layer comprises:
a fluorescing phase comprising at least one luminophore capable of absorbing the reading light and emitting the fluorescent light; and
a quenching phase comprising at least one substance capable of quenching a fluorescence of the at least one luminophore; and
(b) focusing the writing light on a point on one of the active layers on which the information is to be written so as to heat the medium at the point to such a temperature that the fluorescing and quenching phases are irreversibly intermixed.

### Claim 52 (depends on 51)

The method of claim 51, wherein the writing light is ultraviolet light.

### Claim 53 (depends on 51)

The method of claim 51, wherein the writing light is visible light.

### Claim 54 (depends on 51)

The method of claim 51, wherein the writing light is near infrared light.

### Claim 55

A method of recording and reproducing information, the method comprising:
(a) providing a multilayer recordable optical medium for writing by writing light and fluorescent reading by reading light, the reading light causing a generation of fluorescent light, the medium comprising a plurality of recordable medium layers layers, each recordable medium layer comprising:
a substrate that is transparent to the writing light, the reading light, and the fluorescent light; and
an active layer applied onto the substrate;
wherein the active layer comprises:
a fluorescing phase comprising at least one luminophore capable of absorbing the reading light and emitting the fluorescent light; and
a quenching phase comprising at least one substance capable of quenching a fluorescence of the at least one luminophore;
(b) focusing the writing light on a point on one of the active layers on which the information is to be written so as to heat the medium at the point to such a temperature that the fluorescing and quenching phases are irreversibly intermixed; and
(c) irradiating the reading light on at least a portion of the medium to cause the fluorescing phase to emit the fluorescent light where the fluoresing phase has not been intermixed with the quenching phase.

### Claim 56 (depends on 55)

The method of claim 55, wherein the reading light and the writing light are of different wavelengths.

### Claim 57 (depends on 55)

The method of claim 55, wherein the reading light and the writing light are of a same wavelength but different intensities.