Light Emitting Device Light Shielding Frame for Automotive Luminance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current high output light emitting devices for automotive applications face challenges in achieving a large luminance difference between the inside and outside of the light emission surface and efficient light extraction, while also requiring an inexpensive manufacturing method.
Innovation Solution
A method involving the mounting of a light emitting element on a substrate, with a light shielding frame and a light transmissive member supported by a light reflecting member, where the light transmissive member has a smaller outer perimeter than the inner perimeter of the opening, creating a space that is filled with a light reflecting resin to form a light guide support member, and a second reflecting resin is used to surround the light emitting element, enhancing light extraction and luminance difference.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If a heat dissipation layer is formed to cover the periphery of the light emission face, then heat dissipation performance is improved, but manufacturing cost increases and manufacturing complexity increases
Solution Approach 1:
The patent changes the functional parameter of the peripheral structure from heat dissipation to light shielding and light guiding. By forming a light shielding frame with light reflecting members instead of a heat dissipation layer, the invention achieves both light extraction improvement and heat dissipation through the light guiding effect, while using simpler manufacturing processes like injection molding rather than complex coating or lamination processes required for heat dissipation layers.
Solution Approach 2:
The light shielding frame structure serves multiple functions simultaneously: it shields light in unwanted directions, guides light through the light transmissive member to improve extraction, and provides a structure that can be integrated with the substrate. This multi-functionality replaces the need for separate heat dissipation layers, reducing manufacturing steps and cost while maintaining thermal management capabilities.
2Temperature
If a heat dissipation layer is formed to cover the periphery of the light emission face, then heat dissipation performance is improved, but device complexity increases
Solution Approach 1:
The patent merges the light shielding function, light guiding function, and structural support function into a single integrated light shielding frame assembly. The light reflecting members are formed as an integral part of the frame structure, and the entire assembly is mounted on the substrate in one step. This integration eliminates the need for separate heat dissipation layers and reduces the number of components and assembly steps, thereby reducing device complexity.
3Productivity
If the outer perimeter of the light transmissive member is made smaller than the inner perimeter of the opening, then light extraction efficiency is improved, but manufacturing precision requirements increase
Solution Approach 1:
The light reflecting members act as an intermediary element between the light transmissive member and the opening. They fill the space created by the size difference, reflect light that would otherwise be lost, and support the light transmissive member in the correct position. This intermediary structure allows the light transmissive member to have a smaller outer perimeter for improved light extraction while compensating for positioning tolerance through the flexible light reflecting member material (such as resin), thereby reducing the stringency of manufacturing precision requirements.
4Productivity
If light shielding frame and light transmissive member are supported by light reflecting member, then light extraction is improved, but manufacturing steps increase
Solution Approach 1:
The light reflecting members are pre-formed and integrated with the light shielding frame before mounting on the substrate. The frame and reflecting members are prepared as a single pre-assembled unit, which is then mounted onto the substrate with the light transmissive member in one step. This preliminary preparation of the light shielding frame assembly with integrated reflecting members simplifies the overall manufacturing process by reducing the number of separate assembly steps, even though additional processing is required to create the reflecting member structure itself.
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 method allows for the cost-effective production of light emitting devices with a significant luminance difference and efficient light extraction, suitable for automotive applications by optimizing the light emission surface and reducing light leakage.
Implementation Method 1
forming a light guide support member by forming and filling the space with a first light reflecting member
Implementation Method 2
disposing in the opening a plate-shaped light transmissive member
Implementation Method 3
bonding the light guide support member by bonding the upper face of the light emitting element and the second face
Data Source
AI summary
A light emitting device includes: a substrate; a light emitting element disposed on the substrate; a plate-shaped light transmissive member having a first face, a second face opposite to the first face and a lateral face between the first face and the second face, the plate-shaped light transmissive member disposed so that the second face faces a light emission face of the light emitting element; a light shielding frame having an inner perimeter face surrounding the lateral face; a first light reflecting member disposed between the lateral face and the inner perimeter face so as to expose the first face of the light transmissive member; and a second light reflecting member disposed between the first light reflecting member and the substrate to cover a side face of the light emitting element.