Laser Dyeing of Transparent Resin for Uniform Lens Coloring
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing methods for dyeing transparent resin, such as plastic lenses, using laser beams can cause irregular coloring and yellow discoloration, especially when high temperatures are applied uniformly.
Innovation Solution
A method and apparatus that use a laser beam with a wavelength less likely to be absorbed by the dye, combined with a scanning mechanism to control the laser irradiation conditions, ensuring a uniform heating temperature across the dyeing area by adjusting power and speed based on the thickness variations of the lens regions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the entire lens is heated in an oven to fix the dyes, then the dye fixation is achieved, but the lens turns yellow due to high heating temperature
Solution Approach 1:
The patent applies local quality by using a laser beam to heat only the specific regions of the lens where dye fixation is needed, rather than heating the entire lens uniformly. The laser selectively heats the lens surface in controlled areas, achieving dye fixation without subjecting the whole lens to high temperatures that cause yellowing.
Solution Approach 2:
The patent replaces the conventional oven heating system (thermal field) with a laser beam system (optical field converted to localized thermal field). This substitution allows precise spatial and temporal control of the heating process, enabling localized dye fixation without the uniform high-temperature exposure that causes yellow discoloration.
2Object-affected harmful factors
If a laser beam is used to partially heat the lens surface to fix dyes, then yellow discoloration is reduced, but irregular coloring occurs
Solution Approach 1:
The patent applies dynamics by making the laser beam movable and controllable through scanning mechanisms. The laser beam can be dynamically positioned and scanned across different regions of the lens, with adjustable scanning speed and irradiation intensity. This dynamic control ensures uniform heating distribution and consistent dye fixation across the entire lens surface, eliminating irregular coloring while maintaining the benefits of localized heating.
Solution Approach 2:
The patent implements feedback control by monitoring the heating process and adjusting laser irradiation parameters accordingly. The control system regulates the laser output based on the required heating temperature and duration for each lens region, ensuring uniform dye fixation and preventing color irregularities while avoiding excessive heating that causes yellowing.
3Ease of manufacture
If conventional dipping dyeing method is used, then the process is simple, but working conditions are poor and high-refractive lens dyeing is difficult
Solution Approach 1:
The patent replaces the conventional dipping method (mechanical immersion process) with a laser-based heating system. This substitution eliminates the need for large quantities of dye solutions and extended soaking times, improving working conditions while enabling effective dyeing of high-refractive index lenses that are difficult to penetrate with conventional methods.
Solution Approach 2:
The patent applies parameter changes by using laser heating to rapidly raise the temperature of the lens surface to the required fixation temperature in a controlled manner. This temperature parameter control enables dye fixation in high-refractive index lenses without requiring the prolonged exposure or extreme conditions needed in conventional dipping methods.
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 effectively reduces irregular coloring and ensures uniform dye fixation on transparent resin bodies like plastic lenses, maintaining color density and transmittance within acceptable limits, preventing yellow discoloration and enhancing dyeability of high-refractive index materials.
Implementation Method 1
laser beam irradiation means for irradiating a laser beam having a wavelength less likely to be absorbed by the dye toward the transparent resin body
Implementation Method 2
heating temperature on the transparent resin body by irradiation of the laser beam
Implementation Method 3
control means for controlling irradiation of the laser beam by changing a laser beam irradiating condition with respect to a portion of the transparent resin body to be heated so that a heating temperature on the transparent resin body by irradiation of the laser beam is substantially equal throughout an entire area
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A dyeing method in which a transparent resin body having a surface applied with a dye is heated to fix the dye to the transparent resin body comprises a heating step of irradiating a laser beam having a wavelength less likely to be absorbed by the dye toward the transparent resin body applied with the dye on the surface while relatively scanning the laser beam with respect to the transparent resin body to heat a to-be-dyed region of the transparent resin body to fix the dye, wherein the laser beam is irradiation to heat by changing a laser beam irradiating condition with respect to a portion of the transparent resin body to be heated so that a heating temperature on the transparent resin body by irradiation of the laser beam is substantially equal throughout an entire area of the to-be-dyed region.