Porous Ceramic Phosphor Structure for Higher Luminous Efficiency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing ceramic complexes for wavelength conversion are not satisfactory in luminous efficiency, particularly those using rare earth aluminate fluorescent materials.
Innovation Solution
A method for producing a ceramic complex comprising a rare earth aluminate fluorescent material with a specific particle size range and aluminum oxide matrix, incorporating voids within a defined fraction to enhance light diffused reflection and scattering, resulting in improved luminous efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If a sintered body is obtained by mixing inorganic material powder and inorganic fluorescent material powder and melting the inorganic material powder, then the ceramic complex structure is formed, but the luminous efficiency is not satisfactory
Solution Approach 1:
The patent introduces voids (porosity) into the ceramic complex structure, with the void fraction controlled at 1% or more and 10% or less. These voids serve as light scattering centers that increase the path length of incident light through the fluorescent material, enhancing the probability of photon absorption and wavelength conversion. The porous structure effectively traps light within the ceramic complex, improving luminous efficiency by reducing energy loss through direct transmission.
Solution Approach 2:
The patent optimizes multiple parameters including void fraction (1-10%), fluorescent material content (15-50% by mass), and particle size distribution to achieve optimal luminous efficiency. By systematically adjusting these parameters, the patent transforms the conventional dense sintered structure into an optimized porous structure that maximizes light scattering and wavelength conversion while maintaining structural integrity.
2Loss of energy
If voids are introduced to enhance light diffused reflection and scattering, then luminous efficiency is improved, but the structural density decreases
Solution Approach 1:
The patent deliberately creates a porous structure with controlled void fractions between 1% and 10%. This moderate porosity level provides sufficient light scattering centers to improve luminous efficiency while maintaining adequate structural density for mechanical strength. The voids act as optical scattering centers that increase light path length without creating excessive structural voids that would compromise integrity.
Solution Approach 2:
The voids are distributed throughout the ceramic complex structure to create localized light scattering regions. This local modification of density creates optimal light interaction zones while maintaining overall structural integrity. The non-uniform distribution of voids and fluorescent materials creates regions of enhanced optical activity without uniformly reducing structural density throughout the entire component.
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 method enhances luminous efficiency by diffusely reflecting and scattering incident light, allowing for high efficiency wavelength conversion and effective heat dissipation, thereby improving the performance of wavelength conversion members.
Implementation Method 1
the ceramic complex has voids, wherein a void fraction is in a range of 1% or more and 10% or less... diffusely reflecting and scattering incident light
Implementation Method 2
diffusely reflecting and scattering incident light
Implementation Method 3
a rare earth aluminate fluorescent material... converts a wavelength of light emitted from an LED or LD light emitting element
Implementation Method 4
aluminum oxide having a purity of aluminum oxide of 99.0% by mass or more... effective heat dissipation
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Provided are a ceramic complex capable of improving the luminous efficiency, a projector, and a method for producing a ceramic complex. Proposed is a ceramic complex including a rare earth aluminate fluorescent material having an average particle diameter in a range of 15 µm or more and 40 µm or less, aluminum oxide having a purity of aluminum oxide of 99.0% by mass or more, and voids, wherein the content of the rare earth aluminate fluorescent material is in a range of 15% by mass or more and 50% by mass or less relative to a total amount of the rare earth aluminate fluorescent material and the aluminum oxide, and a void fraction is in a range of 1% or more and 10% or less.