LED Light Extraction Efficiency Improvements
22 patents in this list
Updated:
Light extraction from LED devices remains a critical efficiency bottleneck, with internal quantum efficiencies approaching 90% while extraction efficiencies often fall below 50%. Current designs face photon losses through total internal reflection at semiconductor interfaces, absorption in substrate materials, and non-uniform emission patterns that reduce useful light output.
The fundamental challenge lies in maximizing the escape cone for photons while maintaining the electrical and thermal characteristics needed for reliable operation.
This page brings together solutions from recent research—including optimized lens assemblies with controlled air gaps, vertical LED configurations for improved light projection, nanowire architectures, and advanced phosphor implementations. These and other approaches focus on practical ways to enhance extraction efficiency while preserving manufacturability and durability.
1. Adjustable Lighting Fixture with Horizontal Sliding Adjustment Module and Spring-Loaded Pivot Brackets
Intense Lighting, LLC., 2023
An adjustable lighting fixture that maintains high light output even when angled. The fixture has an adjustment module that slides horizontally as it tilts to keep the center of the light beam pointed at the ceiling opening. This allows the module to be tilted without blocking part of the light cone. The module pivots on spring-loaded brackets that hold it in position. The brackets also act as sway bars to guide the module's motion and counterbalance its weight.
2. Horticulture Grow Light Fixture with Edge-Dense LED Arrangement for Uniform Light Dispersion
Global Garden LLC, 2023
Improving the uniformity of light dispersion from horticulture grow light fixtures to deliver more uniform light across a target area and reduce hotspots. This is achieved by rearranging the positioning of the individual LEDs or light emitters so that a greater density of light emitters is used near the edges of the fixture versus the center. By projecting higher levels of light near the edges it brings more light to the periphery and reduces the difference between edge and center light levels.
3. LED Filament Bulb with Flexible Multi-Segment Filament for Omnidirectional Emission
SEOUL SEMICONDUCTOR CO., LTD., 2023
LED filament bulb with omnidirectional light emission and high efficiency. The bulb uses a flexible LED filament shaped to emit uniform light in all directions. The filament has multiple flat segments connected by bendable sections. This allows the filament to be shaped in a non-linear configuration compared to traditional straight filaments. The shaped filament emits light uniformly in 360 degrees. The bendable segments prevent disconnection when the filament is flexed.
4. White LED Lighting with Broad-Spectrum Blue Excitation and Enhanced Phosphor Composition
Intematix Corporation, 2023
White LED lighting that closely mimics natural sunlight and has improved color rendering compared to traditional LEDs. The device uses broad-spectrum blue LEDs as the excitation source along with optimized green-yellow and red phosphors. The broad blue excitation fills in the cyan trough between blue and green phosphors, boosting color rendering. The result is full-spectrum white light that appears more natural, has higher CRI, and reduces eye damage from excessive blue light exposure.
5. LED Lamp with Alternating White and UVA-Emitting Purple LEDs
Xiamen PVTECH Co., Ltd., 2023
LED lamp design to improve color rendering by using a combination of white LEDs and purple LEDs. The purple LEDs emit in the UVA spectrum. The white LEDs provide the main light output while the purple LEDs fill in the UVA range. The combined light enhances color rendering compared to just white LEDs. Alternating white and purple LEDs allows overlap of the UVA range. The purple LEDs can be 400-420nm wavelength.
6. LED Lighting Device with Lens Assembly and Reflector for Enhanced Light Output and Color Consistency
Korrus, Inc., 2023
LED lighting device design that improves light output and color consistency over different angles. The design uses a lens assembly mounted over the LED, with a gap between the lens and elastomer encapsulant. This allows light to reflect off the lens surfaces instead of being absorbed by the elastomer. A reflector in the gap can further control light direction. The lens can also have features like a recess or scattering element to mix light. This reduces color variations and improves uniformity compared to traditional LED encapsulation.
7. LED Lighting Apparatus with Reflective Unit Incorporating Spaced Area and Optical Pattern Layer
LG INNOTEK CO., LTD., 2023
Lighting apparatus with improved luminance using LEDs and reflectors, without increasing thickness or light sources. A reflective unit with a spaced area under each LED increases reflectivity and luminance. The spaced area can be defined by an optical pattern layer to replace a light guide plate.
8. Illuminated Device with Vertically Oriented LEDs on Protruding Arm and Molded Lens Configuration
Innotec, Corp., 2020
Illuminated devices like vehicle warning lights with improved efficiency, durability, and manufacturing simplicity. The device uses a circuit board with LEDs oriented vertically on a protruding arm, with a molded lens over the LED. The circuit board is enclosed in a separate body to protect it. This vertical LED configuration allows optimal light projection and improved efficiency compared to flat boards. The vertical orientation also enables simple molding of the lens over the LEDs. The separate body around the circuit board protects it from the molding process.
9. Light-Emitting Device with Central and Peripheral LED Units for Enhanced Central Brightness
CITIZEN ELECTRONICS CO., LTD., CITIZEN WATCH CO., LTD., 2019
A light-emitting device that provides a large circular light-emitting region with increased brightness in the center by using a central LED unit surrounded by smaller peripheral LED units. The central unit has a larger light-emitting region area compared to the periphery units. This configuration increases the overall light-emitting region size while concentrating more light at the center. It avoids yield issues of making a single large LED and prevents overheating a large substrate.
10. Hybrid White Light Device with Orange Nanowires LED and Narrow Linewidth Blue Laser Diode
King Abdullah University of Science and Technology, 2019
A white light device architecture based on an orange nanowires LED combined with a narrow linewidth blue laser diode for simultaneous illumination and optical wireless communication. The orange nanowires LED provides tunable white light with high color rendering. The blue laser diode enables high-speed data transmission. This hybrid LED/laser system offers improved efficiency, color quality, and data rates compared to conventional phosphor-based white LEDs. The orange nanowires LED has a broad linewidth that fills the spectrum for better color rendering.
11. LED Illumination Apparatus with Aligned Optical Element and LED Arrays
Optovate Limited, 2019
A highly efficient, low-cost LED-based illumination apparatus in which an array of optical elements is aligned with an array of tiny light emitting diodes (LEDs) to improve the directionality and light extraction of the LED emission. The optical elements can be catadioptric, reflective or refractive elements arranged in an array. The LEDs are formed on a separate substrate. When assembled, the optical elements focus and direct the LED light. The optical element array includes electrodes to connect to the LED array for powering the LEDs. The LED and optical element arrays can be manufactured separately and then aligned and combined. This allows optimizing the LED and optical element designs independently.
12. Lighting Fixture with Individually Adjustable LEDs on Variable Pitch and Height Mounting Blocks
David W. Knoble, George V. Preston, 2019
A lighting fixture with individually adjustable LEDs to provide illumination to a plurality of lighting areas. The fixture uses a plurality of mounting blocks with different pitches and heights to angle and position the LEDs in different directions. This allows the LEDs to be aimed independently to focus light in desired areas without using expensive lenses.
13. Light-Emitting Device with Embedded Heat Transfer and Deformation Prevention Members
CITIZEN ELECTRONICS CO., LTD., CITIZEN WATCH CO., LTD., 2019
Light-emitting device with improved heat dissipation and pressure resistance to prevent damage to the sealing resin and internal components. The light-emitting device includes higher thermal conductivity heat transfer members embedded among the light-emitting elements within the sealing resin. These heat transfer members help dissipate heat from the light-emitting elements more effectively, preventing decreased emission intensity. The device also includes deformation prevention members on the substrate around the sealing resin to limit the depth of dents when pressure is applied to the resin. This prevents damage to the internal components and wires from finger or tool pressure during handling or installation.
14. LED Lighting Fixture with Compression-Fit Light Engine and Protrusion-Recess Heat Sink Coupling
OSRAM GmbH, 2019
An LED lighting fixture that provides improved mechanical and thermal coupling of the light engine to the heat sink without using additional elements like adhesives or fixation members. The fixture has a heat sink with a hollow interior. The light engine is inserted into the hollow interior and secured in place by a compression fit against the heat sink walls. The heat sink walls have protrusions that mechanically engage with corresponding recesses on the light engine. This provides both mechanical and thermal coupling between the light engine and heat sink without needing adhesives or fasteners.
15. Light Source Module with Embedded Conductive Layer and Integrated Heat Sink
LG ELECTRONICS INC., 2019
A light source module with improved heat dissipation and fabrication efficiency without resorting to expensive materials. The module has a heat sink with an insulating layer to protect against electrical shock. An electrically conductive layer is embedded in the insulation to provide current to the light source. The conductive layer also has a heat dissipation portion to extract heat.
16. LED Lighting Module with Primary Optics and Reflective Back Surface for Uniform Light Emission
CREE, INC., 2019
Low profile LED lighting module with reduced cross-section and improved light uniformity. The module uses primary optics to customize light output from multiple LEDs and a reflective back surface to redirect and blend the light. A secondary diffuser scatters the light for uniform emission. The module has a minimized height-to-width ratio and reduced LED density to balance efficiency and uniformity.
17. Semiconductor Laser Light Source with Perpendicular Wire and Curved Reflective Substrate
SHARP KABUSHIKI KAISHA, 2018
An eye-safe light source that improves the light emission efficiency while regulating light distribution characteristics. The light source includes a semiconductor laser joined to a substrate with the wire perpendicular to the laser emission direction. The substrate has a curved reflection surface that faces the laser emission end to reflect the laser light. This avoids shadows and scattering bodies between the laser and reflector.
18. Compact LED Light Emitting Device with Integrated Light Guide and Transparent Collimating Element
PHILIPS LIGHTING HOLDING B.V., 2018
LED light emitting device that combines multiple LED sources into a compact high quality light source. The device uses a single light guide element adjacent to the LED output surfaces to efficiently collect the emitted light and guide it to an output surface. A transparent collimating element captures the guided light and reflects any escaping light back into the guide.
19. LED Luminaire with Remote Phosphor and Total Internal Reflection Light Extraction System
Quarkstar LLC, 2018
LED luminaire design that maximizes light extraction from phosphor conversion materials in LED lighting. The luminaire uses a remote phosphor element that scatters light from the LED and a total internal reflection (TIR) extractor element to capture and extract the scattered light. The extractor has a TIR surface that receives scattered light directly from the phosphor and guides it to the exit surface for extraction. The TIR surface reflects light at angles greater than the critical angle for total internal reflection. This allows efficient extraction of converted light that otherwise scatters in random directions from the phosphor.
20. Modular LED Light Fixture with Arc-Shaped Array and Adjustable Convergence
Robert Reynolds, 2018
Modular LED light fixture system with arc-shaped array to achieve high intensity illumination and full spectrum for horticulture and other applications. The system uses LED modules arranged along a curved housing that focuses their light output into a concentrated illuminated area. The modules can be adjusted to converge their light patterns. The fixture allows customization of LED colors and lenses.
Request the PDF report with complete details of all 22 patents for offline reading.
These patents demonstrate a range of developments in light extraction methods. Certain solutions, such as employing denser LED groupings at fixture edges for horticultural lighting, enhance light distribution for particular purposes. Others concentrate on employing flexible filaments to emit light in all directions.