SU1019490A1 - Recording layer of photoptic record medium - Google Patents

Abstract

A PHOTOOPTIC RECORDING MEDIA ID LAYER consisting of an alkaline-halide doped doped with a sensitizing impurity, characterized in that, in order to increase the storage time of optical information on the registering layer without degrading the quality of information, it contains a unformed, unhygienic medium. The quality of the sensitizing impurity is cobalt cations, with the following ratio co1 1 1nents, wt%: Potassium iodide 99.90-99.99 C9 cobalt tions 0.10 -0.01 tons.

Description

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:ABOUT

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The invention relates to photosensitive materials used in optical systems of multiple rewriting and long-term storage of information, namely, the recording layer of a carrier of photo-optical recording, and can be used in optoelectronics in transforming, memory, control optical devices, and also as a recording medium in photography and holography.

A recording layer of a carrier of photo-optical recording based on alkali halide crystals is known, using a manganese-doped sodium chloride crystal as an active medium}.

The disadvantage of this material is low photosensitivity, expressed in prolonged 20 exposure of the crystal under ultraviolet radiation to obtain a spectral response with an optical density equal to one.

The closest to the invention 25 of the technical | Essence and achievable positive effect is an alkali-halide compound of sodium bromide doped with sensitizing alumina impurity. This crystal, treated in sodium vapor, is capable of repeatedly recording optical information from an ultraviolet radiation source at room temperature t2j.

A disadvantage of the known crystal is its high hygroscopicity, which leads to a reduction in the storage time of high-quality optical information on one carrier. - i.

The aim of the invention is to increase the storage time of the optical. This information is recorded on the 45 Loye Buz.uhudsheniya image quality.

This goal is accomplished by the recording layer of the CQ carrier of the optical recording, consisting of an alkaline-halide compound doped with a sensitizing agent, contains, as alkaline-alide compound, potassium iodide,

55 and as a sensitizing agent, cobalt cations, with the following coacoat ratio, wt.%:

Iodide, l

potassium 99.90-99.99 60

Cations

cobalt 0.10-0.01

This crystal can be obtained by melt growth. Polos gs

RESULTS The effect is due to the fact that cobalt ions have a catalytic effect on the ionization process of impurity complexes formed after annealing the crystal in potassium vapors and after the effect of ultraviolet radiation, color centers, and recording media on the crystal. At the same time, potassium iodide crystal, having a high photosensitivity, is much less hygroscopic than the known crystal. The optimum concentration of cobalt ions, which further determines the highest photosensitivity, is 0.01-0.10 May,%. The choice of potassium iodide as alkaline-halide compound is explained by the fact that; that the ionization potential is less than that of other alkali halide compounds.

Experimentally, it was found that the dependence of the exposure time on the cobalt concentration has the form of a curve with a minimum that is limited to the range O, 01-0.10 May. cobalt content in the crystal.

At other cobalt concentrations, the exposure time increases significantly for; obtaining a given optical density of the recording signal.

Example. Get rb (the host layer. Crystals of potassium iodide, containing different concentrations of the dopant cobalt ions, wt.%:

.KZSo

1.99.90 / 0.10

2.99,980,02

3.99,990.01

All crystals were sensitized to ultraviolet radiation by annealing in potassium vapor and then cooled to room temperature.

As a result of the test, the photographic materials obtained had the following characteristics. .

Erasing optical information in all cases is carried out by holding the recording layer for 3-5 seconds at 350-380 C.

After temperature erasure, repeated recording of optical information on these crystals can be carried out thirty times without loss of recording quality.

Practical use of the proposed recording layer of the photo-optical recording in comparison with the known ones will ensure the speed of recording information due to high sensitivity, long-term storage of the recorded information without deterioration in quality and ease of processing, due to the perfect cleavage of the potassium iodide crystal.

Initial sensitized condition

Thallium-doped sodium bromide

YoDid. potassium doped {cobalt

and

The recording quality remains at the same level until appearance with dimness.

5-8 h

12 + 1

3-5 months

8T1 3-5 months.

10 + 1 3-5 months

Claims (1)

PHOTOOPTIC RECORDING RECORDING LAYER, consisting of an alkali halide compound doped with a sensitizing impurity, characterized in that, in order to increase the storage time of optical information on the recording layer without compromising the quality of the information, it contains iodine as an alkali halide compound and as a sensitizing impurity - cobalt cations, in the following ratio of components, wt.%: Potassium iodide 99.90-99.99 Cobalt cations 0.10 -0.01