Rotating Phosphor Light Engine for High-Luminance Heat Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current light sources, particularly those using static phosphor configurations, face limitations in luminance due to thermal quenching from high blue laser power densities, and existing solutions like spinning phosphor wheels are bulky and inefficient for compact applications.

Innovation Solution

A compact laser light engine design featuring a ceramic phosphor ring mounted on a spinning transparent rod, where blue laser light is focused onto the phosphor using a domed-shaped end, improving heat management and allowing higher pumping power densities, and utilizing alternative phosphor geometries for better thermal spreading and reduced hotspot formation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Illumination intensity

If high blue laser power density is used to increase luminance, then light output intensity is improved, but thermal quenching occurs reducing efficiency

Engineering Contradiction:
ImproveluminanceVSAvoidthermal quenching
Core Design Contradiction:
Illumination intensityVSLoss of energy

Solution Approach 1:

The patent applies the dynamics principle by rotating the phosphor element at high speeds (e.g., 30,000 RPM or higher). This rotational motion dynamically distributes the heat generated by high-power blue laser irradiation across the entire phosphor volume and to the surrounding heat-sinking structures, preventing localized thermal quenching and enabling sustained high luminance output without efficiency loss

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent transitions from static phosphor geometry to a rotating phosphor element with extended temporal dimension. The rotation introduces a time-based dimension where heat is continuously redistributed, and the phosphor geometry itself is designed with radial and axial dimensions (e.g., ring shapes, domed surfaces) that enhance heat dissipation pathways in multiple spatial directions

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Temperature

If spinning phosphor wheel is used to improve heat management, then thermal quenching is reduced, but device size increases

Engineering Contradiction:
Improveheat managementVSAvoiddevice size
Core Design Contradiction:
TemperatureVSVolume of moving object

Solution Approach 1:

The patent applies nesting by integrating the phosphor element directly onto the rotation axis or mounting it on a compact rod that spins in place. The heat-sinking structures are nested within or around the rotating assembly, and the entire mechanism is contained within a compact housing where components are nested concentrically, dramatically reducing the overall device volume compared to traditional separate phosphor wheel designs

Inventive Principle:
Principle #7Nested doll (Nesting)

Solution Approach 2:

The patent merges multiple functions into the rotating assembly: the phosphor element, the rotation mechanism, and the heat-sinking structures are combined into a single integrated rotating unit. This consolidation eliminates the need for separate stationary heat-sinking components and reduces the number of mechanical parts, thereby minimizing device size while maintaining effective heat management

Inventive Principle:
Principle #5Merging (Combining)

3Volume of moving object

If compact phosphor geometry is used to reduce device size, then volume is reduced, but heat dissipation capability decreases

Engineering Contradiction:
Improvedevice sizeVSAvoidheat dissipation
Core Design Contradiction:
Volume of moving objectVSTemperature

Solution Approach 1:

The patent employs composite material structures where the phosphor is deposited on or integrated with materials having high thermal conductivity (e.g., metal substrates, ceramic coatings, or thermally conductive polymers). This composite construction provides dual functionality: maintaining compact geometry while the thermally conductive material serves as an integrated heat-sinking pathway, enabling efficient heat dissipation from the small phosphor volume

Inventive Principle:
Principle #40Composite materials

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 design achieves higher luminance and compactness compared to static phosphor solutions, with improved heat management and reduced thermal quenching, enabling tighter beam angles and miniaturized luminaires while maintaining comparable collimated beam performance.

Implementation Method 1

the luminescent material comprising element (100) comprises a luminescent material (110) configured to emit luminescent material light (111) upon irradiation with first light (11)

Methodology Applied
Scientific EffectPhotoluminescence: Photoluminescence

Implementation Method 2

blue laser light is focused onto the phosphor using a domed-shaped end

Methodology Applied
Scientific EffectOptical focusing: Focusing

Implementation Method 3

The spinning rod can be made from sapphire, providing improved heat management of the phosphor

Methodology Applied
Scientific EffectThermal conduction: Conduction (thermal)

Implementation Method 4

improving heat management and allowing higher pumping power densities, and utilizing alternative phosphor geometries for better thermal spreading and reduced hotspot formation

Methodology Applied
Scientific EffectRotational heat distribution: Convection

Data Source

PatentEP4103997B1Compact laser-based light generating device
Publication Date: 2023.11.08 SIGNIFY HOLDING BV
  • EP4103997B1 patent drawingFigure 1A~1D
  • EP4103997B1 patent drawingFigure 1E~1F
  • EP4103997B1 patent drawingFigure 2A

AI summary

The invention provides an arrangement (1) comprising a device (1000), wherein the device (1000) comprises a luminescent material comprising element (100) and a light transmissive element (200), wherein: (a) the device (1000) has a first device axis (A1); (b) the luminescent material comprising element (100) comprises a luminescent material (110) configured to emit luminescent material light (111) upon irradiation with first light (11), wherein the luminescent material comprising element (100) has a first length (L1) and a characteristic first dimension (D1) perpendicular to the first length (L1), wherein D1/L1<1; wherein the luminescent material comprising element (100) is configured at a non-zero first distance (r1) from the first device axis (A1), and wherein the luminescent material comprising element (100) at least partly surrounds the first device axis (A1); (c) the light transmissive element (200) is transmissive for the first light (11), wherein the light transmissive element (200) comprises a element light entrance part (201and an element light escape part (202), wherein the element light escape part (202) and the luminescent material (110) are radiationally coupled; wherein one or more of the following applies: (i) the first device axis (A1) intersects the light transmissive element (200), and (ii) the light transmissive element (200) at least partly surrounds the first device axis (A1); and (d) the luminescent material comprising element (100) is in thermal contact with one or more of (a) the light transmissive element (200) and (b) an optional thermally conductive element (300).