Polarized Plastic Lens Peripheral Edge Bonding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional methods for manufacturing polarized plastic lenses result in variations in the position of the polarized film due to design and manufacturing precision issues, leading to lenses being thicker than standard plastic lenses for spectacles.
Innovation Solution
A method involving a polarized plastic lens configuration where the polarized film is positioned between two lens base materials with a minimum distance of 0.3 mm to 0.7 mm from the object-side surface, using a convex-shaped polarized film and high refractive power lens materials, and bonding the peripheral edge of the polarized film to the mold to maintain precise positioning during manufacturing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the polarized film is retained using a gasket with an insertion groove, then the polarized film can be supported and positioned, but the lens thickness increases beyond that of normal plastic lenses due to positioning variations
Solution Approach 1:
The invention changes the retention mechanism from mechanical insertion into a groove to adhesive bonding, and optimizes the bonding area parameters ( peripheral edge portion only) to achieve both precise positioning and thin lens thickness. The adhesive bonding method eliminates the need for deep grooves while maintaining positioning accuracy.
Solution Approach 2:
The invention segments the bonding area to only the peripheral edge portion of the polarized film, rather than bonding the entire film. This segmentation allows the central area to remain thin while the edges provide sufficient bonding strength and positioning accuracy.
2Ease of manufacture
If the polarized film is inserted into a previously provided insertion groove, then the film position is determined by gasket design, but variations in film thickness and curved surface precision cause position variations after molding
Solution Approach 1:
The adhesive agent automatically conforms to the actual shape and position of the polarized film's peripheral edge, eliminating the need for precise pre-designed grooves. The adhesive bonding process itself accommodates variations in film thickness and curved surface precision, providing self-adjusting positioning.
3Length of stationary object
If the minimum distance between the object-side surface and the polarized film is reduced below 0.3 mm, then the lens can be made thinner, but it becomes difficult to form the eyeball-side surface during manufacture
Solution Approach 1:
The polarized film is bonded to the mold's object-side surface in advance before lens molding. This preliminary action ensures the film is securely positioned and protected during the subsequent molding process, enabling the formation of the eyeball-side surface even with minimal distance (0.3-0.7 mm) between the object-side surface and film.
4Ease of manufacture
If the minimum distance between the object-side surface and the polarized film exceeds 0.7 mm, then the eyeball-side surface can be easily formed, but the lens thickness becomes larger than normal finished lenses
Solution Approach 1:
The invention optimizes the distance parameter to a specific range (0.3-0.7 mm) that balances manufacturability and thinness. This parameter optimization, combined with adhesive bonding of the peripheral edge portion, enables the lens to achieve normal thickness while maintaining ease of eyeball-side surface formation.
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 allows for the production of thin polarized plastic lenses with a thickness similar to standard lenses, ensuring accurate positioning and reducing manufacturing variability, while using polyvinyl alcohol as the polarized film for enhanced properties.
Implementation Method 1
a peripheral edge portion of the polarized film and the mold for the first lens base material are bonded to each other by using an adhesive agent
Implementation Method 2
a polarized plastic lens for spectacles... for blocking a specific polarization directional light reflected by a water surface, etc.
Implementation Method 3
the raw material monomer is injected around the polarized film... and polymerizing and curing the injected monomer
Data Source
Figure 1(A)~1(B)
Figure 2
Figure 3(A)~3(B)
AI summary
There is provided a polarized plastic lens for spectacles configured to be thin having almost the same thickness as the thickness of a normal plastic lens for spectacles, and a method for manufacturing the polarized plastic lens for spectacles, the plastic lens including a first lens base material having an object-side surface; a second lens base material having an eyeball-side surface; and a polarized film provided between the first lens base material and the second lens base material so that a minimum value of a distance between the polarized film and the object-side surface is 0.3 mm or more and 0.7 mm or less.