LED Optical Cavity with Egg-Shaped Cross Section for Biased Illumination
Solution Overview
Problem
Conventional light emitting diodes (LEDs) lack the capability to efficiently manage light distribution, often resulting in unequal illumination patterns, such as casting equal amounts of light on streets and houses, which is undesirable in street lighting applications, and there is a need for a compact, economical, and energy-efficient solution to redirect light effectively.
Innovation Solution
An optical apparatus that processes light emitted by LEDs using refraction and total internal reflection to redirect light from non-strategic directions towards desired areas, featuring a body of optical material with refractive and reflective surfaces, and a cavity design that optimizes light management by eliminating non-functional portions, allowing for efficient molding and reduced material usage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If conventional unbiased LEDs are mounted facing down to illuminate streets, then the LED structure is simple and easy to manufacture, but the light distribution is uneven with equal illumination on both street and house sides which is undesirable
Solution Approach 1:
The LED assembly is segmented into functional zones using a reflective cup structure that divides the emitted light into street-side and house-side portions, allowing independent control and optimization of light distribution to each area
Solution Approach 2:
A reflective cup structure is introduced as an intermediary element between the LED and the environment, which actively manages and redirects light paths to achieve the desired biased illumination pattern while maintaining manufacturing simplicity
2Illumination intensity
If optical elements are added to redirect light from house-side to street-side, then light distribution is improved, but device complexity and material usage increase
Solution Approach 1:
The reflective cup structure serves multiple functions simultaneously: it acts as a mechanical mounting component, a light redirecting element, and a structural support, thereby improving light distribution without proportionally increasing device complexity
Solution Approach 2:
The optical system utilizes the natural reflection properties of the cup structure and the LED's own emitted light to achieve redirection, eliminating the need for additional active optical components or complex control mechanisms
3Illumination intensity
If traditional optical elements are used to manage light, then light redirection is achieved, but the size and material usage of the optical apparatus increase
Solution Approach 1:
The design extracts and utilizes the reflective properties inherent in the mounting structure itself, removing the need for separate optical redirecting elements and thereby reducing overall material usage while maintaining light redirection capability
Solution Approach 2:
The optical functional elements are merged with the mechanical mounting structure, creating a unified component that performs both structural and optical functions, thus reducing the total quantity of materials required
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 solution effectively biases light distribution to achieve desired illumination patterns, enhancing street-side illumination while reducing material and size, thereby supporting cost-effective and efficient LED deployment in various lighting applications.
Implementation Method 1
An optical apparatus that processes light emitted by LEDs using refraction and total internal reflection to redirect light from non-strategic directions towards desired areas
Implementation Method 2
An optical apparatus that processes light emitted by LEDs using refraction and total internal reflection to redirect light from non-strategic directions towards desired areas
Data Source
AI summary
A light source, for example a light emitting diode, can emit light and have an associated optical axis. The source can be deployed in applications where it is desirable to have illumination biased laterally relative to the optical axis, such as in a street luminaire where directing light towards a street is beneficial. The source can be coupled to an optic that comprises a cavity. At least a portion of the cavity can have an outline that is egg-shaped in cross section. A backside of the cavity (or a backside portion of the optic) can have an irregular shape for receiving the light emitting diode, for example to form a receptacle shaped to fit a circuit.