Optical Lens Preform Molding with Dual Temperature Zones
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for producing optical moldings, particularly optical lenses, face challenges in achieving excellent optical quality with reduced internal stresses and long cooling times due to the use of high mold temperatures, which are necessary for optimal tool temperatures but result in inefficient production processes.
Innovation Solution
A method involving the production of a preform at a lower mold temperature (between 60°C and 80°C) and a cover layer at a higher temperature (between 90°C and 130°C), with reduced pressure, allowing for simultaneous injection molding of cover layers and using transparent thermoplastics like polycarbonate, which reduces internal stresses and shortens cooling times.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If high mold temperature is used for optimal tool temperature, then optical quality is improved, but cooling time increases significantly
Solution Approach 1:
The molding process is segmented into two distinct stages with different temperature requirements: preform molding at lower temperature (60-80°C) and cover layer molding at higher temperature (90-130°C). This segmentation allows each stage to be optimized independently, reducing overall cooling time while maintaining optical quality in the final product.
Solution Approach 2:
The preform is molded first at a lower temperature to establish the basic structure, and then the cover layer is molded over it at the optimal temperature for optical quality. This preliminary action approach allows the final optical surfaces to be formed at optimal temperatures without requiring the entire mold to be at high temperature throughout the process.
2Stability of the object's composition
If high mold temperature is used, then internal stresses are reduced, but production time increases
Solution Approach 1:
The process is divided into two temperature zones: the preform stage uses lower temperature (60-80°C) for rapid cooling and high productivity, while the cover layer stage uses higher temperature (90-130°C) to reduce internal stresses in the optical surfaces. This segmentation allows both objectives to be achieved in different stages.
Solution Approach 2:
Different temperature conditions are applied to different parts of the molding process: the preform (internal structure) is molded at lower temperature, while the cover layers (optical surfaces) are molded at higher temperature. This local quality approach ensures that each region receives the temperature treatment most appropriate for its function.
3Manufacturing precision
If optimal tool temperature is used for each layer, then optical quality is maintained, but production efficiency decreases
Solution Approach 1:
The optimal temperature is applied selectively only to the cover layer stage (90-130°C), while the preform stage operates at lower temperature (60-80°C). This segmentation maintains optical quality where it matters most (at the optical surfaces) while improving overall production efficiency through reduced cooling time.
Solution Approach 2:
The mold temperature parameter is changed between stages: lower temperature (60-80°C) for preform molding to improve efficiency, then higher temperature (90-130°C) for cover layer molding to ensure optical quality. This dynamic parameter change optimizes both productivity and quality.
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
This approach enables the production of optical moldings with improved optical imaging properties and reduced internal stresses while significantly reducing production time and maintaining high-quality surface impressions.
Implementation Method 1
injection molding a first thermoplastic and at least one cover layer is produced on the preform by injection molding a second thermoplastic
Implementation Method 2
the temperature of the mold to produce the preform being at 30% to 60%, based on the temperature in °C, is lower than the temperature of the mold for producing the at least one cover layer
Data Source
Figure 1~2
Figure 3
Figure 4~5
AI summary
The invention relates to a method for producing a molded optical part (2), in particular a lens element (2), by producing a preform (4) in a molding tool by injection molding a first plastic, and by producing at least one covering layer (6.1, 6.2) on the preform (4) by injection molding a second plastic, the temperature of the molding tool for producing the preform (4) being 30% to 60% lower than the temperature of the molding tool for producing the at least one covering layer (6.1, 6.2).