Speckle Imaging Focus Detection Using Incoherent Reference
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Imaging apparatuses using speckle patterns struggle to detect focus accurately, resulting in low-resolution images and inability to acquire depth information due to large particle noise and incapability of capturing speckle images effectively.
Innovation Solution
An imaging apparatus and system that utilize both coherent and incoherent light sources, incorporating a speckle imaging unit, a non-speckle imaging unit, and a focus detection unit to capture and adjust focal positions, allowing for aberration correction and region-of-interest specification to enhance image resolution and focus detection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of information
If speckle imaging is performed using coherent light, then depth information and focus detection capability are improved, but measurement precision deteriorates due to large particle noise
Solution Approach 1:
The patent combines speckle imaging and non-speckle imaging systems into a single integrated apparatus. The speckle imaging unit captures depth information and focus data, while the non-speckle imaging unit provides high-precision reference images. By merging these two imaging modalities and their respective image processing functions, the system achieves both depth information acquisition and high measurement precision without the limitations of separate systems.
2Device complexity
If monocular camera is used for speckle pattern measurement, then device complexity is reduced, but manufacturing precision deteriorates due to inability to identify focus
Solution Approach 1:
The patent introduces a reference object with known depth information as an intermediary element in the imaging path. This reference object serves as a mediator between the simple monocular camera system and the requirement for accurate focus detection. By capturing the reference object's known depth characteristics and comparing them with the captured speckle patterns, the system can calculate accurate depth information and focus status without requiring complex multi-camera or active focus detection hardware.
3Loss of information
If coherent light is used for imaging, then depth information acquisition is improved, but object-generated harmful factors increase due to speckle noise
Solution Approach 1:
The patent converts the harmful speckle noise generated by coherent light into a useful signal for depth measurement. Instead of treating speckle patterns as mere noise to be eliminated, the system analyzes the statistical properties and temporal variations of speckle patterns to extract depth information. By combining this speckle-based depth information with non-speckle imaging data, the system transforms the previously harmful coherent light speckle noise into a beneficial source of depth measurement capability.
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 high-resolution speckle image capture and accurate focus detection, improving the ability to observe moving fluids and biological tissues, such as blood vessels, by minimizing noise and enhancing depth information acquisition.
Implementation Method 1
Speckle is a random interference/diffraction pattern due to scattering or the like in an optical path
Implementation Method 2
the speckle caused by scattering of the imaging object is observed on the image plane
Implementation Method 3
a non-speckle image obtained from reflected light of the imaging object irradiated with the incoherent light
Data Source
AI summary
Provided is an imaging technique capable of detecting a focus even in an imaging apparatus of a speckle image.The imaging apparatus includes a coherent light source that irradiates an imaging object with coherent light, an incoherent light source that irradiates the imaging object with incoherent light, a speckle imaging unit that captures a speckle image obtained from scattered light of the imaging object irradiated with the coherent light, a non-speckle imaging unit that captures a non-speckle image obtained from reflected light of the imaging object irradiated with the incoherent light, and a focus detection unit that detects a focus of the speckle imaging unit on the basis of a focal position of the non-speckle imaging unit.