Optical Glass Composition for High Index and Devitrification Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing optical glasses lack the flexibility to achieve high refractive index, high transmittance, and devitrification resistance stability, limiting their application in advanced optical systems and devices.
Innovation Solution
An optical glass composition comprising 5% to 35% La3+, 5% to 25% Si4+, 5% to 35% Nb5+, 5% to 35% Al3+, and 45% to 80% of a total content rate of Ti4+, Zr4+, Nb5+, Ta5+, and Al3+, manufactured using a floating melting method to avoid crucible contact, ensuring high refractive index, transmittance, and devitrification resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If conventional optical glass compositions are used, then manufacturing is simpler, but refractive index and transmittance cannot be sufficiently increased
Solution Approach 1:
The patent applies parameter changes by systematically adjusting the chemical composition parameters of the optical glass, specifically setting La3+ content at 5-35 mol%, Nb5+ at 5-35 mol%, and the ratio of (Ti4+ + Zr4+) to total cations at 45-80%, to achieve the target refractive index of 1.95-2.15 and transmittance of 80% at 420nm or less
Solution Approach 2:
The patent uses composite materials by combining multiple metal oxides (La2O3, Nb2O5, TiO2, ZrO2, Al2O3, SiO2, B2O3) in specific proportions to create a new optical glass composition that achieves high refractive index and transmittance properties that cannot be obtained with conventional single-component or simple composite glasses
2Adaptability or versatility
If high refractive index glass is developed, then optical system design flexibility increases, but devitrification resistance stability deteriorates
Solution Approach 1:
The patent changes the chemical composition parameters by incorporating specific amounts of Al3+ (5-35 mol%) and controlling the ratio of high-field-strength cations (Ti4+, Zr4+, Nb5+, Ta5+) to total cations at 45-80%, which enhances devitrification resistance while maintaining the high refractive index needed for optical system design flexibility
Solution Approach 2:
The patent uses Al2O3 and SiO2 as intermediary components that mediate between the high refractive index requirements (from La2O3 and Nb2O5) and devitrification resistance stability, acting as network formers and stabilizers that prevent crystallization while allowing the optical properties to be optimized
3Ease of manufacture
If crucible melting method is used, then manufacturing process is simpler, but glass purity and transmittance are compromised
Solution Approach 1:
The patent extracts the glass from contact with crucible materials by using a floating melting method where the molten glass floats on a protective flux layer, eliminating contamination from crucible walls and achieving the high purity required for 80% transmittance at 420nm or less
Solution Approach 2:
The patent introduces a protective flux layer as an intermediary between the molten glass and the crucible, preventing direct contact and contamination while still allowing heat transfer for melting, thus maintaining both manufacturing feasibility and glass purity
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 optical glass achieves a refractive index of 1.95 to 2.15, transmittance of 80% at 420 nm or less, and devitrification resistance with a temperature difference of 80°C to 200°C, enabling stable production of large glass gobs for advanced optical elements and systems.
Implementation Method 1
an optical glass having a high refractive index has been required
Implementation Method 2
manufactured using a floating melting method to avoid crucible contact
Implementation Method 3
devitrification resistance stability deteriorates
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
An optical glass includes, by mol% of a cation, 5% to 35% of a content rate of La3+; 5% to 25% of a content rate of Si4+; 5% to 35% of a content rate of Nb5+; 5% to 35% of a content rate of Al3+; and 45% to 80% of a total content rate of Ti4+, Zr4+, Nb5+, Ta5+, and Al3+ (Ti4+ + Zr4+ + Nb5+ + Ta5+ + Al3+).