Interference Coating Stability via Ion Beam Organic Layer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing ophthalmic lenses with interference coatings, particularly antireflection coatings, face issues with stability over time, leading to changes in optical properties and aesthetics, and are prone to mechanical deformations and cracking, which affect their performance and saleability.
Innovation Solution
Incorporating a low refractive index layer formed by deposition under an ion beam using organic precursor materials, specifically activated species containing silicon, carbon, hydrogen, and optionally nitrogen and oxygen, as an intermediate layer in the interference coating, which enhances stability and thermomechanical properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional inorganic anti-reflective coating is deposited on ophthalmic lenses, then the coating provides initial anti-reflective performance, but the optical properties (especially chroma and reflection coefficients) change over time during storage and use
Solution Approach 1:
The patent applies preliminary action by depositing an intermediate organic layer before the inorganic anti-reflective layers. This organic layer is prepared in advance to prevent subsequent chroma shifts and optical property changes that would otherwise occur during storage and use. The layer acts as a protective barrier that stabilizes the underlying inorganic layers, ensuring long-term optical stability without requiring post-deposition adjustments.
Solution Approach 2:
The patent employs composite materials by combining organic and inorganic layers in a multistack configuration. The intermediate layer consists of organic compounds (such as silanes or silicon oxides) deposited by chemical vapor deposition, while outer layers use inorganic materials for anti-reflective properties. This composite structure leverages the stability of organic materials to protect the optical properties while maintaining the functional benefits of inorganic anti-reflective coatings.
2Manufacturing precision
If the anti-reflective coating is optimized for initial optical performance, then target reflection coefficients and chroma are achieved at deposition, but the coating becomes sensitive to mechanical deformations and cracking during cutting and mounting
Solution Approach 1:
The patent applies segmentation by dividing the anti-reflective coating into multiple independent stacks, each with specific functional roles. The intermediate organic layer is segmented into discrete deposits between inorganic layers, creating a modular structure. This segmentation allows each layer to be optimized independently - the organic layers provide mechanical flexibility and crack resistance, while the inorganic layers provide optical performance - resolving the contradiction between manufacturing precision and mechanical strength.
Solution Approach 2:
The patent utilizes parameter changes by varying the deposition parameters, material composition, and layer thickness across different stacks. The organic intermediate layers have different refractive indices, densities, and mechanical properties compared to the inorganic layers. By adjusting these parameters, the coating achieves both precise optical control (reflection coefficients, chroma) and enhanced mechanical resilience against deformation and cracking during subsequent processing.
3Ease of manufacture
If a multilayer interference coating is deposited to achieve target optical properties, then aesthetic appeal and anti-reflective effectiveness are optimized, but the coating requires complex quality control to ensure stability over time
Solution Approach 1:
The patent introduces an intermediate organic layer as a mediator between the substrate and the inorganic anti-reflective layers. This intermediary layer simplifies quality control by providing a stable foundation that prevents chroma shifts and optical property changes in the overlying inorganic layers. The organic layer acts as a buffer that isolates the sensitive inorganic layers from environmental factors, reducing the need for complex quality control measures while ensuring long-term stability.
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 results in stable optical properties over time, improved resistance to mechanical deformations, and increased critical temperature, ensuring consistent performance and aesthetics while simplifying quality control and manufacturing processes.
Implementation Method 1
a layer A having a refractive index less than or equal to 1.55, which constitutes an intermediate layer, directly in contact with the outer layer of the interference coating... said layer A being obtained by deposition, under an ion beam, of activated species from at least one compound C, in gaseous form
Implementation Method 2
deposition, under an ion beam, of activated species from at least one compound C, in gaseous form containing in its structure at least one silicon atom
Data Source
AI summary
The invention relates to an article comprising a substrate having at least one main surface coated with a multilayer interference coating, said coating containing a layer A having a refractive index less than or equal to 1.55. The article is characterised in that: layer A forms either the outer interference coating layer or an intermediate layer that is in direct contact with the outer interference coating layer, said outer interference coating layer being a layer B having a refractive index less than or equal to 1.55; layer A is obtained by ion beam deposition of activated species from at least one compound C in gaseous form and containing in its structure at least one silicon atom, at least one carbon atom, at least one hydrogen atom and, optionally, at least one nitrogen atom and/or at least one oxygen atom, layer A being deposited in the presence of nitrogen and/or oxygen when compound A does not contain nitrogen and/or oxygen; and layer A is not formed from inorganic precursor compounds.