Semiconductor Light Emitting Device Cap with Inclined Opening

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing semiconductor light emitting devices face inefficiencies in light output due to return light being reflected back onto the LED or laser diode, leading to reduced output and shortened lifespan, and require larger cup structures to manage light reflection and wavelength conversion effectively.

Innovation Solution

A semiconductor light emitting device design featuring a cap with a penetrating opening that widens outward, allowing emission light to pass through a transparent member containing wavelength conversion or scattering materials, minimizing return light reflection and absorption, and optimizing the cap's shape to enhance light guidance and heat dissipation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Illumination intensity

If a cup structure is used to seal the LED and contain phosphor material, then wavelength conversion and light gathering are improved, but return light is reflected back onto the LED causing deterioration of LED characteristics and reduced output

Engineering Contradiction:
Improvelight gathering efficiencyVSAvoidLED life characteristics
Core Design Contradiction:
Illumination intensityVSReliability

Solution Approach 1:

The patent extracts the harmful function of the cup's inner surface by removing its reflective property. The inclined surface is designed with a light-absorbing material or black coating to prevent return light reflection, thereby eliminating the harmful effect while preserving the cup's sealing and light-gathering functions.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent converts the harmful reflected return light into a beneficial absorption effect. By designing the inclined surface to absorb rather than reflect light, the previously harmful return light path is transformed into a light-absorbing mechanism that prevents LED deterioration while maintaining overall light output efficiency.

Inventive Principle:
Principle #22Blessing in disguise (Convert harm into benefit)

2Illumination intensity

If the cup depth is increased to provide a large inclined surface area for reflecting light, then light reflection efficiency is improved, but the device size increases and shock resistance decreases

Engineering Contradiction:
Improvelight reflection efficiencyVSAvoidshock resistance
Core Design Contradiction:
Illumination intensityVSStrength

Solution Approach 1:

The patent applies asymmetry by designing the cup with an inclined surface rather than a symmetric cylindrical shape. This inclined configuration optimizes the light reflection path and reduces the required cup depth, thereby improving shock resistance while maintaining light reflection efficiency.

Inventive Principle:
Principle #4Asymmetry

Solution Approach 2:

The patent changes the geometric configuration from a vertical depth-oriented structure to an inclined surface-oriented structure. By tilting the reflective surface, the light reflection function is achieved with reduced depth, effectively utilizing spatial arrangement in another dimension to resolve the contradiction between light reflection efficiency and shock resistance.

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

3Illumination intensity

If the mount surface area is increased to accommodate LED mounting and light reflection, then LED mounting and light reflection are improved, but the cup size increases

Engineering Contradiction:
Improvelight reflection capabilityVSAvoidcup size
Core Design Contradiction:
Illumination intensityVSVolume of stationary object

Solution Approach 1:

The patent utilizes the curved inclined surface of the cup to maximize light reflection capability within a compact area. The curved geometry allows efficient light reflection without requiring a large flat mount surface, thereby reducing the overall cup size while maintaining light reflection performance.

Inventive Principle:
Principle #14Spheroidality (Curvature)

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 significantly improves light outgoing efficiency, reduces return light impact on the semiconductor element, and enhances the device's shock resistance and heat management, leading to increased light emission intensity and extended lifespan.

Implementation Method 1

The transparent member contains a wavelength conversion material that absorbs the emission light from the semiconductor light emitting element and converts the wavelength of the emission light

Methodology Applied
Scientific EffectWavelength conversion: Photoluminescence

Implementation Method 2

The transparent member contains a wavelength conversion material that absorbs the emission light from the semiconductor light emitting element and converts the wavelength of the emission light, or a light scattering material that scatters the emission light from the semiconductor light emitting element

Methodology Applied
Scientific EffectLight scattering: Scattering

Implementation Method 3

The cap member is provided with a penetrating opening that has an inclined portion so that the penetrating opening is getting wider toward the outside from the inside where semiconductor light emitting element is mounted

Methodology Applied
Scientific EffectLight guidance through inclined surface: Refraction

Data Source

PatentEP1926154B1Semiconductor light emitting device
Publication Date: 2019.12.25 NICHIA CORP
  • EP1926154B1 patent drawingFigure 1
  • EP1926154B1 patent drawingFigure 2~4
  • EP1926154B1 patent drawingFigure 5~6

AI summary

A semiconductor light emitting device is provided which allows emission light from a light source to efficiently outgo from the semiconductor light emitting device so that the light emission intensity of the semiconductor light emitting device is increased. A penetrating opening (K) is formed in the substantially central part of a cap member (3) to communicate the interior side to the exterior side the cap member (3). The penetrating opening (K) has an inclined portion (5). The inclined portion (5) is opposed to and spaced away from a semiconductor light emitting element (4), and includes a light entering portion through which emission light from the semiconductor light emitting element (4) passes. The opening width of the inclined portion (5) is getting wider from the light entering portion in the light traveling direction so that the inclined portion (5) is tapered. The emission light from the semiconductor light emitting element (4) can effectively outgo from the semiconductor light emitting device.