LED Reading Light Current Controller for Uniform Brightness
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Modern LED manufacturing technologies produce LEDs with reduced forward voltages, making it difficult for existing power supply units in civilian aerospace to maintain uniform light intensity, as the voltage drop from the test current may no longer be below the forward voltage, and manufacturers face significant technological efforts to adapt power supply units, while airlines require new LEDs to operate without new power supply units.
Innovation Solution
An LED reading light with a separate current controller integrated within, utilizing a coding resistor that signals the maximum power supply current, allowing the current controller to adjust the operating current to achieve the desired light intensity, enabling operation with existing power supply units and accommodating varying LED light yields.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If modern LED light means with reduced forward voltages are used, then power dissipation is reduced, but the voltage drop from the test current may no longer remain below the forward voltage, causing the LED to emit light during measurement
Solution Approach 1:
The patent introduces a capacitor as an intermediary energy storage element between the power supply unit and the LED light means. During the measurement phase, the capacitor stores energy from the test current without causing the LED to light up. During the operation phase, the capacitor releases this stored energy to drive the LED at the desired intensity. This mediator allows the system to overcome the limitation of reduced forward voltages in modern LEDs while maintaining accurate measurement capabilities.
2Illumination intensity
If the power supply units are adapted to modern LED light means, then the desired light intensity can be achieved, but significant technological effort and cost are required for modifying existing systems
Solution Approach 1:
The patent implements a self-service approach where the LED reading light unit autonomously regulates its own operating parameters. The control unit measures the forward voltage of the integrated LED light means and automatically adjusts the operating current accordingly, using the previously determined relationship between forward voltage and optimal current. This eliminates the need for external power supply unit modifications, as each LED unit independently adapts to its specific LED characteristics, thereby achieving desired light intensity without system-wide technological overhaul.
3Adaptability or versatility
If airlines require new LEDs to operate with existing power supply units, then compatibility is maintained, but uniform light intensity across different LED types becomes difficult to achieve
Solution Approach 1:
The patent employs parameter changes by dynamically adjusting the operating current based on the measured forward voltage of each LED light means. The control unit establishes a relationship between forward voltage and optimal operating current, then uses this relationship to automatically select the appropriate current parameter for each LED type. This allows different LED types with varying forward voltages to operate uniformly with the same power supply unit, achieving both compatibility and uniform light intensity through adaptive parameter adjustment.
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
Enables the LED reading light to maintain consistent light intensity across different LED types, allowing for seamless integration with existing power supply units and enabling dimming functions, while accommodating the variability in modern LED light yields without requiring new power supply units.
Implementation Method 1
an LED light means (12) for giving off light with a desired light intensity
Implementation Method 2
a coding component, in particular a coding resistor (14), with an electrical parameter which specifies the magnitude of power supply current
Data Source
AI summary
The LED reading light, in particular for a passenger transportation vehicle such as, for example, an airplane, a bus, or a ship, is provided with two power supply connections (17) for connection to a power supply unit (16), an LED light means for giving off light with a desired light intensity, and a coding component (14), in particular a coding resistor, which is connected to at least one of the power supply connections (17), where the electrical parameter of the coding component (14) specifies the magnitude of a power supply current which can be provided for the LED light means by the power supply unit (16). Furthermore, the LED reading light is provided with a current controller (18) which is connected between the coding component (14) and the LED light means (12) and provides an operating current for the operation of the LED light means (12). The coding component (14) exhibits the electrical parameter for the provision of the maximum possible power supply current and the current controller (18) adjusts the operating current to a value at which the LED light means (12) gives off light with the desired light intensity.