Wavelength Conversion Member Reflection Layer Light Leak
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
High-luminance and high-power light sources with phosphor layers suffer from reduced fluorescent light conversion efficiency due to increased temperature, leading to light leak and inefficient light use, as well as challenges in separating the plane of incidence and emission of excitation and fluorescent light.
Innovation Solution
A light source device with a wavelength conversion member having reflection layers on its surfaces to efficiently direct excitation light and converted light, using low-refractive index layers to reduce losses and a cooling system to manage heat, while optimizing the refractive index ratio to enhance light reflection and emission efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If high-luminance and high-power light is used as excitation light to improve luminance, then luminance is improved, but fluorescent light conversion efficiency deteriorates because the temperature of the phosphor layer rises
Solution Approach 1:
The patent introduces a new spatial dimension by providing a reflection layer on the first surface (excitation light incident surface) of the phosphor layer. This reflection layer redirects converted light that would otherwise leak out through the first surface back into the phosphor layer, effectively adding a light management dimension that was previously absent. This resolves the contradiction by maintaining high luminance output while reducing energy loss through strategic light redirection in the optical path.
Solution Approach 2:
The patent converts the harmful effect of light leakage through the first surface into a beneficial effect. By placing a reflection layer on the first surface, the converted light that would be lost is instead reflected back into the phosphor layer, where it can be redirected to the third surface for efficient extraction. This transforms the harmful light leak into a beneficial recycling mechanism that improves overall light use efficiency while maintaining high luminance.
2Use of energy by moving object
If the spot diameter of excitation light is increased to reduce optical density, then optical density is reduced, but the area of fluorescent emitted light increases making it difficult to efficiently take into the optical system
Solution Approach 1:
The patent utilizes the reflection layer on the first surface to control the spatial distribution and direction of converted light. By reflecting converted light back into the phosphor layer and guiding it toward the third surface, the system maintains a manageable light area that can be efficiently coupled into the optical system, even when the excitation spot diameter is increased to reduce optical density.
3Area of stationary object
If the plane of incidence of excitation light and the plane of emission of fluorescent light are separated to reduce fluorescent light area, then fluorescent light area is reduced, but light leak occurs in the phosphor layer causing deterioration in light use efficiency
Solution Approach 1:
The reflection layer on the first surface acts as an intermediary element that manages the interaction between converted light and the phosphor layer. It reflects converted light that would otherwise leak out back into the phosphor layer, where it can be properly directed toward the third surface. This intermediary reflection mechanism maintains the separated plane configuration for compact light area while preventing energy loss through light leak.
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 solution achieves high light use efficiency by minimizing light leaks and losses, ensuring efficient emission of converted light and effective heat management, resulting in brighter and higher-quality images in projection systems.
Implementation Method 1
A first reflection layer that transmits the excitation light and reflects the converted light is provided on the first surface
Implementation Method 2
even when the converted light is made incident on the first surface at an incident angle equal to or smaller than a total reflection angle, the converted light is reflected by the first reflection layer
Implementation Method 3
a wavelength conversion member having a plurality of surfaces and configured to convert the excitation light made incident from the first light source into converted light in a second wavelength band different from the first wavelength band
Data Source
AI summary
A light source device includes a first light source configured to emit excitation light in a first wavelength band and a wavelength conversion member having a plurality of surfaces and configured to convert the excitation light made incident from the first light source into converted light in a second wavelength band different from the first wavelength band. The wavelength conversion member includes a first surface on which the excitation light is made incident, a second surface opposed to the first surface, and a third surface that emits the converted light. A first reflection layer that transmits the excitation light and reflects the converted light is provided on the first surface.