Endoscope Illumination Device Using Laser and Diffusion Sheet
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing endoscope illuminating devices face inefficiencies due to heat generation from halogen and xenon lamps, and high-power LEDs suffer from low coupling efficiency and phosphor saturation issues, leading to reduced luminance and imaging quality.
Innovation Solution
An illuminating device with a light source assembly comprising a semiconductor laser, diffusion sheet, dichroic mirror, collimating lenses, and a fluorescent disc, which uniformly diffuses and converts light to increase luminance and energy density, coupled with a lens coupling assembly for improved light homogenization and guidance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If high-power LED array is used as light source, then energy efficiency is improved, but coupling efficiency with fibers is poor due to Etendue limitation
Solution Approach 1:
The patent divides the illumination system into separate functional modules: laser light source, beam expanding optics, diffuser for uniformity, and fiber coupling optics. This segmentation allows each component to be optimized independently, achieving high energy efficiency from the laser while managing the coupling challenge through dedicated optical elements.
Solution Approach 2:
The patent introduces intermediary optical elements (beam expanding lenses, diffusers, and coupling optics) between the laser source and the fiber bundle. These intermediaries transform the laser beam characteristics to match the fiber acceptance angles, resolving the Etendue mismatch while maintaining high energy efficiency.
2Illumination intensity
If excitation light intensity is increased to improve luminance, then light source utilization is improved, but phosphor saturation and quenching occur
Solution Approach 1:
The patent uses a diffuser to create non-uniform excitation light distribution across the phosphor surface, with lower intensity at the center and higher intensity at the edges. This local quality variation prevents phosphor saturation and quenching at high-intensity regions while maintaining high overall luminance output.
Solution Approach 2:
The patent changes the spatial distribution parameter of the excitation light intensity profile, transforming it from a concentrated high-intensity beam to a controlled non-uniform distribution. This parameter change allows operating at high overall intensity without causing localized phosphor damage.
3Illumination intensity
If halogen lamp or xenon lamp is used as light source, then illumination is achieved, but too much heat is generated requiring heat insulating elements
Solution Approach 1:
The patent replaces thermal-based illumination sources (halogen and xenon lamps) with a laser-based optical system. This substitution eliminates the need for heat-generating incandescent filaments or arc discharge mechanisms, providing illumination with minimal heat generation and removing the requirement for heat insulating elements.
4Temperature
If heat insulating element is added between light source and endoscope, then heat management is improved, but photoelectric conversion efficiency decreases and miniaturization is hindered
Solution Approach 1:
The patent extracts and removes the heat insulating element from the optical path by switching to a laser light source that generates minimal heat. This extraction eliminates the barrier to photoelectric conversion and enables direct coupling of the light source to the endoscope, facilitating miniaturization.
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 enhances luminance by preventing phosphor quenching, facilitates miniaturization, and improves light guiding efficiency, resulting in better endoscopic imaging quality.
Implementation Method 1
the diffusion sheet is disposed between the first light source and the dichroic mirror, and the diffusion sheet is used to diffuse light of the first light source
Implementation Method 2
a dichroic mirror; wherein the diffusion sheet is disposed between the first light source and the dichroic mirror
Implementation Method 3
a laser can be used to remotely excite the phosphor to achieve white light illumination
Data Source
AI summary
An illuminating device and an endoscope having the same are described. The illuminating device includes a light source assembly, and the light source assembly includes a first light source, a diffusion sheet and a dichroic mirror. The diffusion sheet is disposed between the first light source and the dichroic mirror, and the diffusion sheet is used to diffuse light of the first light source.