Optical Device Plasmon Excitation Fluorescence Coupling Efficiency
Solution Overview
Problem
The coupling efficiency of fluorescence and surface plasmons in plasmon coupling and emitting devices is limited by the low extinction coefficients of ordinary phosphor materials, which restricts the improvement of efficiency and luminance, even when the phosphor layer thickness is optimized to several 10 nm.
Innovation Solution
Incorporating metal particles into the phosphor layer to enhance the absorptivity and excitation of surface plasmons, increasing the fluorescence conversion efficiency by utilizing the field enhancement effect of surface plasmons on the metal particles, and optimizing the dielectric constants and structures to improve light extraction and directivity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the phosphor layer thickness is reduced to several 10 nm to improve coupling efficiency of fluorescence and surface plasmons, then the coupling efficiency improves, but the fluorescence conversion efficiency becomes lower due to insufficient light absorption
Solution Approach 1:
The patent applies composite materials by combining phosphor particles with metal particles (having high extinction coefficients) to form a composite phosphor layer. This composite structure enables the layer to maintain both high light absorption capability and high fluorescence-to-plasmon coupling efficiency, resolving the contradiction between thin film thickness requirements for coupling and sufficient thickness for absorption.
Solution Approach 2:
The patent changes the material parameters of the phosphor layer by incorporating metal particles with high extinction coefficients. This parameter change allows the phosphor layer to achieve sufficient light absorption even at reduced thickness, thereby maintaining high fluorescence conversion efficiency while improving coupling efficiency to surface plasmons.
2Use of energy by moving object
If the phosphor layer thickness is increased to improve light absorption, then the fluorescence conversion efficiency improves, but the coupling efficiency of fluorescence and surface plasmons decreases
Solution Approach 1:
The composite phosphor layer containing metal particles with high extinction coefficients enables the system to achieve high light absorption efficiency without requiring increased layer thickness. This maintains strong fluorescence generation while keeping the phosphor layer thin enough to ensure effective coupling between fluorescence and surface plasmons.
Solution Approach 2:
By changing the material composition parameters and incorporating metal particles with high extinction coefficients, the patent achieves high light absorption in a thin layer, thereby simultaneously improving both fluorescence conversion efficiency and plasmon coupling efficiency without the need to increase layer thickness.
3Device complexity
If ordinary phosphor materials are used to maintain material availability, then the device complexity remains low, but the absorptivity and luminance are insufficient
Solution Approach 1:
The patent uses composite materials combining phosphor particles with metal particles to create a phosphor layer with enhanced absorptivity. This composite approach significantly improves luminance and light absorption efficiency while maintaining relatively simple device structure and manufacturing processes.
Solution Approach 2:
The patent changes the optical parameters of the phosphor layer by incorporating metal particles with high extinction coefficients. This parameter change dramatically improves the absorptivity and luminance of the device without significantly increasing device complexity or manufacturing difficulty.
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 significantly enhances the coupling efficiency and luminance of the optical device by increasing the absorptivity and fluorescence conversion efficiency, leading to improved performance in light source and projection type display devices.
Implementation Method 1
a phosphor layer, a metal layer, and an exit layer are successively laminated. In the phosphor layer, incident light emitted from a light emitting device causes fluorescence to occur. The fluorescence couples with free electrons that are contained in a metal layer. As a result, surface plasmons are excited on the metal surface.
Implementation Method 2
In the phosphor layer, incident light emitted from a light emitting device causes fluorescence to occur
Implementation Method 3
In the exit layer, the surface plasmons are converted into light having a predetermined exit angle. The light having a predetermined exit angle is emitted from the exit layer.
Data Source
AI summary
An optical device featuring high efficiency and luminance is provided. The optical device includes carrier generation layer that causes fluorescence to occur with incident light, plasmon excitation layer that excites first surface plasmons with said fluorescence, carrier generation layer being laminated on carrier generation layer, and exit layer that extracts the first surface plasmons or light that occurs on an opposite surface of carrier generation layer contact surface of plasmon excitation layer to the outside. Carrier generation layer contains metal particles that excite second surface plasmons with said incident light.