RGB LED Illumination Controller for Uniform Light Amount Resolution

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional lighting devices for board work machines with red, green, and blue light sources often experience uneven light amounts, leading to insufficient recognition accuracy due to dimming issues, which affects the precision of image processing.

Innovation Solution

The illuminating unit includes a lighting controller that adjusts the light amounts of red, green, and blue LEDs in the same number of gradations, with the upper limit of the dimming range for stronger light sources being smaller than that of weaker light sources, ensuring uniform light source resolutions and sufficient brightness.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Illumination intensity

If the maximum light amounts of the light sources of the three colors are allowed to vary, then the brightness of each color can be optimized independently, but the light amount resolutions of the light sources become different, resulting in uneven light amounts even after dimming

Engineering Contradiction:
Improvebrightness of each colorVSAvoidlight amount uniformity
Core Design Contradiction:
Illumination intensityVSManufacturing precision

Solution Approach 1:

The patent changes the parameter of dimming range upper limits for different colored light sources. Specifically, it sets different upper limits for the dimming ranges of red, green, and blue LEDs based on their respective maximum light amounts. This parameter adjustment ensures that all three colors can be dimmed to the same minimum light amount with uniform resolution, while still allowing each color to operate at its optimal brightness level when needed.

Inventive Principle:
Principle #35Parameter changes

2Manufacturing precision

If dimming is applied to equalize the light amounts of the three colors, then light amount uniformity can be improved, but the light sources may not provide sufficient brightness for accurate image recognition

Engineering Contradiction:
Improvelight amount uniformityVSAvoidoverall brightness
Core Design Contradiction:
Manufacturing precisionVSIllumination intensity

Solution Approach 1:

The patent implements a dynamic lighting control system that can independently adjust the brightness of each colored light source based on imaging requirements. The control device selects appropriate light sources and adjusts their intensity dynamically, allowing the system to provide sufficient overall brightness while maintaining uniform light amounts through the differentiated dimming range configuration.

Inventive Principle:
Principle #15Dynamics

3Measurement precision

If the light sources of the three colors are individually lit up to illuminate the target object, then three monochromatic images can be obtained for precise recognition, but the varying light amount resolutions make it difficult to achieve uniform illumination

Engineering Contradiction:
Improverecognition accuracyVSAvoidillumination uniformity
Core Design Contradiction:
Measurement precisionVSManufacturing precision

Solution Approach 1:

The patent employs a control device that monitors and adjusts the light output of each colored light source. By implementing feedback control with differentiated dimming ranges, the system can maintain uniform light amounts across all three colors while preserving the ability to individually illuminate the target object for capturing three monochromatic images with high recognition accuracy.

Inventive Principle:
Principle #23Feedback

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 configuration ensures that the light sources provide consistent and bright illumination, reducing variability and enhancing recognition accuracy by making the light amounts of the three colors more uniform.

Implementation Method 1

a red light source configured to emit a red light, a green light source configured to emit a green light, and a blue light source configured to emit a blue light

Methodology Applied
Scientific EffectLight Emitting Diode: Light Emitting Diode

Data Source

PatentEP4007482B1Illuminating unit
Publication Date: 2024.07.17 FUJI CORP
  • EP4007482B1 patent drawingFigure 1
  • EP4007482B1 patent drawingFigure 2~4
  • EP4007482B1 patent drawingFigure 5

AI summary

An illuminating unit for illuminating an imaging range of a monochromatic camera mounted on a board work machine for working on a board includes a red light source configured to emit a red light, a green light source configured to emit a green light, a blue light source configured to emit a blue light, and a lighting controller configured to adjust independently respective light amounts of the red light source, the green light source, and the blue light source in the same number of gradations within a predetermined dimming range. In the red light source, the green light source, and the blue light source, the upper limit of the dimming range of the light source having the strong light amount is smaller than the upper limit of the dimming range of the light source having the weak light amount.