Aliphatic Polymer Recording Layer for High-Density Optical Storage

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing recording media face challenges in maintaining low one-photon absorption at short wavelengths, particularly with multiphoton absorption compounds, due to changes in electronic states and interactions with polymers during the curing process, leading to reduced recording and reading sensitivity.

Innovation Solution

A recording medium comprising an aliphatic polymer and a multiphoton absorption compound with specific bonds, such as carbon-carbon double bonds, carbon-nitrogen double bonds, or carbon-carbon triple bonds, is developed, ensuring minimal one-photon absorption at wavelengths like 405 nm by minimizing interactions and maintaining the electronic state of the compound.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If multiphoton absorption compounds are used to increase recording density, then recording capacity is improved, but one-photon absorption increases leading to reduced reading sensitivity

Engineering Contradiction:

Improverecording capacityVSAvoidone-photon absorption

Core Design Contradiction:

Quantity of substanceVSObject-affected harmful factors

Solution Approach 1:

The patent changes the chemical parameters of the polymer from aromatic to aliphatic structure, which fundamentally alters the optical absorption characteristics. This parameter change in the polymer type eliminates the harmful one-photon absorption while preserving the multiphoton absorption capability of the recording compound, thus resolving the contradiction between recording capacity and reading sensitivity

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent creates a composite material system combining aliphatic polymer with multiphoton absorption compounds. This composite structure allows the aliphatic polymer to serve as an inert matrix that does not interfere with the optical properties of the recording compound, enabling high recording capacity while maintaining low one-photon absorption for good reading sensitivity

Inventive Principle:

Principle #40Composite materials

2Quantity of substance

If laser light with short wavelength is used to create finer spots, then recording density is improved, but transmittance decreases leading to reduced reading efficiency

Engineering Contradiction:

Improverecording densityVSAvoidlight transmittance

Core Design Contradiction:

Quantity of substanceVSUse of energy by moving object

Solution Approach 1:

The patent changes the wavelength parameter of the laser light to 405 nm, which is a short wavelength that enables fine spot size for high recording density. Simultaneously, the aliphatic polymer composition is optimized to ensure high transmittance at this specific wavelength, resolving the contradiction between recording density and reading efficiency

Inventive Principle:

Principle #35Parameter changes

3Reliability

If recording layer thickness is increased to improve signal strength, then reading reliability is improved, but one-photon absorption increases reducing overall efficiency

Engineering Contradiction:

Improvereading reliabilityVSAvoidone-photon absorption

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The aliphatic polymer creates an optically inert environment for the multiphoton absorption compound. This inert matrix does not absorb the 405 nm light, allowing the recording layer to be sufficiently thick for reliable signal detection while minimizing one-photon absorption losses throughout the layer thickness

Inventive Principle:

Principle #39Inert atmosphere (Inert environment)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The solution achieves high transmittance (>80%) and reduces one-photon absorption, enabling efficient recording and reading with minimal interference, thereby enhancing recording density and capacity.

Implementation Method 1

a multiphoton absorption compound containing at least one bond selected from the group consisting of a carbon-carbon double bond, a carbon-nitrogen double bond, and a carbon-carbon triple bond, and having a multiphoton absorption characteristic

Methodology Applied

Scientific EffectMultiphoton absorption: Absorption (EM radiation)

Implementation Method 2

the transmittance of the at least one recording layer in the thickness direction with respect to light having a wavelength of 405 nm is greater than or equal to 80%

Methodology Applied

Scientific EffectLight transmission: Light

Data Source

PatentUS12112780B2Recording medium, information recording method, information reading method, and composition for producing recording layer

Publication Date: 2024.10.08 PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO LTD

AI summary

A recording medium includes a recording layer. The recording layer includes an aliphatic polymer, and a multiphoton absorption compound containing at least one bond selected from the group consisting of a carbon-carbon double bond, a carbon-nitrogen double bond, and a carbon-carbon triple bond, and having a multiphoton absorption characteristic. When the thickness of the recording layer is 100 μm, the transmittance of the recording layer in the thickness direction with respect to light having a wavelength of 405 nm is greater than or equal to 80%.