Light Source Module With Substrate Light Extraction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional light source modules with LED dies suffer from reduced luminous efficiency due to light being blocked by electrode layers and increased thickness from wire bonding, making them unsuitable for small and lightweight electronic devices.
Innovation Solution
A light source module design featuring a substrate with a first and second covering layer, a luminous layer, and a supporting base with metal connection layers and a passivation layer, which allows currents to flow and emit light without wire bonding, reducing thickness and enhancing luminous efficiency by reflecting and projecting light through the substrate.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If conventional LED die structure with P-type and N-type electrodes is used, then electrical connection is achieved, but light beam is blocked and lost by electrode layers reducing luminous efficiency
Solution Approach 1:
The patent extracts and removes the harmful P-type covering layer and conducting film layer that block light output. By eliminating these light-blocking layers while maintaining the essential P-type and N-type electrode structures, the invention allows the light beam to pass through the substrate without being absorbed or blocked, thereby resolving the contradiction between achieving electrical connection and preventing light loss.
Solution Approach 2:
The patent changes the optical properties of the substrate by making it transparent or translucent to the emitted light wavelength. This allows the substrate to transition from being a light-blocking component to a light-transmitting component, enabling the light beam to pass through effectively and improving luminous efficiency while maintaining structural integrity.
2Length of moving object
If wire bonding process is used to connect electrodes, then electrical connection is achieved, but overall thickness of package structure increases
Solution Approach 1:
The patent merges the electrical connection function and light transmission function into a single integrated substrate structure. The substrate simultaneously serves as the mounting platform for the LED die, the electrical connection path for current flow, and the light transmission medium. This consolidation eliminates the need for separate wire bonding components and processes, thereby reducing overall thickness while maintaining manufacturability.
Solution Approach 2:
The substrate is designed to perform multiple functions simultaneously: it provides mechanical support for the LED die, conducts electrical current from the electrodes, and transmits the emitted light beam to the external environment. This multi-functional design eliminates the need for separate wire bonding structures, reducing the overall package thickness while maintaining ease of manufacture through a simplified single-substrate approach.
3Illumination intensity
If light beam is outputted upwardly from multiple quantum well, then light generation is achieved, but portion of light beam is blocked and lost by covering layers and electrodes
Solution Approach 1:
The patent extracts and removes the light-blocking P-type covering layer and conducting film layer from the multi-layered stack structure. By eliminating these intermediate layers that absorb or block the upwardly traveling light beam, the invention allows maximum light output intensity to be achieved while maintaining the essential functional layers needed for LED operation.
Solution Approach 2:
The patent modifies the optical properties of the substrate to be transparent or translucent to the emitted light wavelength, enabling the substrate to transmit the light beam effectively. This optical property change allows the light beam to pass through the substrate without significant absorption or scattering, thereby maximizing illumination intensity while maintaining a relatively simple structural configuration.
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 design achieves 1.6 to 3 times the luminous efficiency of conventional modules by reducing thickness and minimizing light loss, facilitating uniform light output and improved heat dissipation.
Implementation Method 1
When a current is applied to a semiconductor material of Group III-V such as gallium nitride (GaN), gallium phosphide (GaP), gallium arsenide (GaAs) or indium phosphide (InP), electrons recombine with holes. Consequently, the extra energy is released from a multiple quantum well (MQW) in the form of photons, and the light beam visible to the eyes is generated.
Implementation Method 2
The second metal connection layer and the first metal connection layer are combined together to reflect the light beam
Data Source
AI summary
A light source module includes a substrate, a first covering layer, a second covering layer, a luminous layer and a supporting base. The luminous layer is arranged between the first covering layer and the second covering layer. The luminous layer emits a light beam in response to a first current flowing through the first covering layer and a second current flowing through the second covering layer. The light beam is projected to surroundings through the substrate. The supporting base is electrically connected with the first covering layer and the second covering layer. The supporting base includes a circuit board and a passivation layer. When a portion of the light beam projected to the supporting base is reflected by the passivation layer, the portion of the light beam is projected to the surroundings through the substrate.