Photo-mask Absorption Layer for UV Stain Prevention
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Ultraviolet light used to harden sealants in display devices can cause stain defects by radiating to liquid crystals, leading to inefficiencies in the manufacturing process.
Innovation Solution
A photo-mask with a transparent substrate and a light shielding layer that includes an absorption layer of polycrystal silicon or amorphous silicon to block ultraviolet light, preventing it from reaching the liquid crystals and sealants, while allowing specific wavelengths to harden the sealant.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If ultraviolet light is used to harden the sealant, then the sealant curing efficiency is improved, but stain defects occur in the liquid crystal due to unwanted UV radiation
Solution Approach 1:
The UV light source is segmented into different wavelength components, with only the specific wavelength range (365-405 nm) that cures the sealant being transmitted, while other wavelengths that cause liquid crystal staining are blocked by the selective transmission filter
Solution Approach 2:
A selective transmission filter is introduced as an intermediary component between the UV light source and the substrates. This filter mediates the UV radiation by allowing only beneficial wavelengths to pass through while blocking harmful wavelengths, thus resolving the contradiction between curing efficiency and stain prevention
2Object-affected harmful factors
If a conventional photo-mask is used to block UV light, then liquid crystal staining is prevented, but sealant hardening becomes incomplete or non-uniform
Solution Approach 1:
Instead of using a conventional photo-mask that blocks all UV wavelengths, the invention changes the wavelength parameter of the UV light by using a selective transmission filter. This allows precise control over which wavelengths reach the sealant, ensuring uniform and complete hardening while preventing liquid crystal staining
3Object-affected harmful factors
If all ultraviolet wavelengths are blocked to protect liquid crystal, then stain defects are prevented, but sealant cannot be hardened
Solution Approach 1:
The UV light spectrum is treated with local quality differentiation, where specific wavelength ranges (365-405 nm) are allowed to pass through to cure the sealant, while other wavelength ranges are blocked to prevent liquid crystal staining. This selective wavelength management enables both sealant hardening and stain prevention simultaneously
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
Prevents stain defects by selectively blocking ultraviolet light that could polymerize the liquid crystals and allows controlled hardening of the sealant, ensuring precise manufacturing of display devices.
Implementation Method 1
the light shielding layer includes an absorption layer configured to absorb ultraviolet light
Implementation Method 2
The first photoinitiator may be reactive to ultraviolet light having a wavelength range of from about 380 nm to about 400 nm
Data Source
AI summary
A photo-mask is capable of preventing stain defects and a method for fabricating a liquid crystal display device using the photo-mask which achieves the same capability. The photo-mask includes a transparent substrate configured to transmit ultraviolet light and a light shielding layer configured to block ultraviolet light on a surface of the transparent substrate. The light shielding layer includes an absorption layer configured to absorb ultraviolet light.