Microscope Illumination Device with Structured Dark Field Optics
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current high-resolution optical microscopy techniques, such as transmission and reflection microscopy with visible light illumination, are limited by a lateral image resolution that does not surpass 180 nm, and existing dark field illumination systems suffer from misalignment issues that introduce background noise and reduce contrast.
Innovation Solution
A dark field illumination system with a light source fixed on an entrance slit of a condenser and an objective aligned with the condenser, utilizing structured illumination and an iris to produce mixed illumination, which includes a high aperture microscope objective and an adapter or axicon lens for optimal alignment and light economy, generating diffraction fringes and a narrowed point spread function.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional transmission and reflection microscopy with visible light illumination is used, then the system is simple to operate, but the lateral image resolution does not surpass 180 nm
Solution Approach 1:
The illumination system is segmented into multiple functional components: a light source, a condenser with adjustable aperture, and an objective lens with iris diaphragm. This segmentation allows independent optimization of each component to achieve super-resolution while maintaining operational simplicity through modular design.
Solution Approach 2:
The system employs dynamic control of the condenser aperture and objective iris to switch between different illumination modes (dark field, bright field, hollow cone). This dynamic adjustability enables the system to adapt to different resolution requirements without requiring multiple fixed systems, thus improving resolution while managing complexity.
2Object-affected harmful factors
If dark field illumination is used to improve contrast, then contrast and light economy are enhanced, but misalignment of the condenser introduces background light or noise
Solution Approach 1:
The system incorporates feedback mechanisms through the adjustable condenser aperture and objective iris that allow real-time optimization of alignment. Users can adjust these components to maximize contrast while minimizing background noise, providing operational feedback that guides precise alignment without requiring complex pre-alignment procedures.
Solution Approach 2:
The dynamic adjustability of the condenser aperture and objective iris enables operators to optimize alignment during operation. This dynamic control allows the system to compensate for minor misalignments and maintain low background noise levels while preserving the high contrast benefits of dark field illumination.
3Illumination intensity
If the condenser aperture is increased to improve illumination, then more light reaches the sample, but direct light enters the objective and reduces contrast in dark field mode
Solution Approach 1:
The illumination path is segmented by the condenser aperture, which separates direct light from scattered light paths. This segmentation allows the system to deliver high illumination intensity to the sample while preventing direct light from entering the objective, thereby maintaining high contrast in dark field mode.
Solution Approach 2:
The condenser aperture acts as an intermediary element that controls light distribution. It allows sufficient light to reach the sample for high illumination intensity while blocking direct light paths that would otherwise enter the objective and reduce contrast, thus mediating between illumination intensity and contrast requirements.
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 system achieves resolutions below 120 nm and improved contrast, surpassing conventional diffraction limits, with enhanced light economy and the ability to observe small objects like viral particles and nano-materials with superior spatial resolution.
Implementation Method 1
a light source which is fixed on an entrance slit of a condenser
Implementation Method 2
an objective aligned with the condenser such that the objective and the condenser are adjusted to find a focus spot on a sample
Implementation Method 3
generating diffraction fringes and a narrowed point spread function
Data Source
AI summary
The present invention is a dark field illumination system including a light source which is fixed on an entrance slit of a condenser and an objective aligned with the condenser such that the objective and the condenser are adjusted to find a focus spot on a sample. The present invention essentially uses structured illumination to achieve an improved illumination system. The present invention also includes a system and method wherein the objective is coupled to an iris and aligned with the condenser such that when the iris is closed only dark field images are produced, and when the iris is open, direct entrance of light is allowed into the objective and bright field illumination is produced.