Digital holographic microscope with a multiple offset interferometer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing digital holographic microscopes have limited depth measurement ranges, especially when measuring cells and solids in fluids, due to the limitations of single-wavelength interferometers, which restrict the uniqueness range of measurements.
Innovation Solution
A digital holographic microscope system that uses a birefringent plate to generate different beam offsets and polarization directions, creating distinct fringe patterns for enhanced uniqueness range without requiring additional wavelengths.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a single-wavelength interferometer is used, then the device complexity is low, but the depth measurement range is limited to one wavelength
Solution Approach 1:
The patent segments the measurement process by capturing multiple holograms with different beam offsets (shear amounts) and combining them through Fourier transformation. This segmentation of the measurement space allows extension of the uniqueness range beyond a single wavelength limitation while maintaining a relatively simple single-wavelength interferometer setup.
Solution Approach 2:
The patent introduces an additional dimension to the measurement by varying the beam offset (shear amount) in addition to the optical path difference. This creates a two-dimensional measurement space (optical path difference × beam offset) that extends the depth measurement range through synthetic wavelength concepts without requiring multiple physical wavelengths.
2Measurement precision
If multiple wavelengths are added to increase measurement range, then the depth measurement range increases, but the device complexity increases
Solution Approach 1:
The patent uses beam offset (shear amount) as an intermediary parameter to achieve synthetic wavelength effects. Instead of directly adding multiple wavelengths, the system introduces beam offset as a mediating variable that creates effective synthetic wavelengths through the interference pattern variations, thereby extending measurement range without the complexity of multiple wavelength sources.
Solution Approach 2:
The patent changes the beam offset parameter (shear amount) across multiple measurements to synthesize extended wavelength information. By systematically varying this parameter and processing the resulting holograms through Fourier transformation, the system achieves extended uniqueness range equivalent to multiple wavelengths but with a single-wavelength source.
3Measurement precision
If beam offset is increased to extend measurement range, then the uniqueness range increases, but the fringe width decreases
Solution Approach 1:
The patent employs dynamic adjustment of beam offset values across multiple measurements rather than using a fixed offset. By systematically varying the offset and combining results through Fourier transformation, the system maintains adequate fringe visibility in each individual measurement while achieving extended uniqueness range through the combined data set.
Solution Approach 2:
The patent uses multiple partial measurements at different beam offsets and combines them to achieve the complete extended range. Each individual measurement with a specific offset provides partial information with adequate fringe width, and the combination of these partial measurements through Fourier synthesis achieves the full extended uniqueness range.
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 an extended measurement range with minimal additional components, allowing for high-resolution, high-contrast imaging of biological and medical samples, including cells and fluids, by adjusting intensity ratios and fringe patterns.
Implementation Method 1
A digital holographic microscope system that uses a birefringent plate to generate different beam offsets and polarization directions
Implementation Method 2
A digital holographic microscope system that uses a birefringent plate to generate different beam offsets and polarization directions
Implementation Method 3
In an interferometer, the fringe pattern is created by the inclination of two beams relative to each other
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
The invention relates to a device, such as a digital holographic microscope (1), for detecting and processing a first full image of a measurement object, measured with a first offset, wherein an arrangement is provided for generating at least one further full image with at least one offset that differs from said first offset.