Anamorphic Optics Asymmetric Magnification Line-Scan Imager
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Line-scan imagers face challenges in increasing line-scan frequency without degrading spatial resolution or damaging objects due to high-intensity electromagnetic radiation, which can cause thermal damage, especially when imaging smaller objects or on moving conveyor belts.
Innovation Solution
The use of an optical system comprising a pair of anamorphic optics providing afocal magnification, where the first anamorphic optic focuses light in a cross-track direction and the second optic further magnifies it in an along-track direction, allowing for improved signal beam amplification without significant cross-track magnification, thus enhancing resolution and reducing distortion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the line-scan frequency is increased to improve resolution and detect smaller objects, then the spatial resolution is improved, but the time for the sensor to produce an electrical signal decreases, lowering the electrical signal magnitude
Solution Approach 1:
An optical system with asymmetric magnification is introduced as an intermediary between the object and the line-scan imager. The optical system includes a first anamorphic optic that magnifies in the along-track direction and a second anamorphic optic that magnifies in the cross-track direction. This optical intermediary allows the sensor to effectively observe a larger area and collect more light, thereby maintaining adequate electrical signal magnitude even at higher line-scan frequencies improved spatial resolution
Solution Approach 2:
The optical system changes the parameters of light transmission by introducing asymmetric magnification. The first anamorphic optic changes the focal length and beam geometry in the along-track direction, while the second anamorphic optic adjusts the beam in the cross-track direction. This parameter transformation allows the system to maintain signal strength while achieving higher resolution imaging at increased scan frequencies
2Manufacturing precision
If the intensity of the electromagnetic radiation source is increased to compensate for shorter exposure time, then the electrical signal magnitude is improved, but the power required for the electromagnetic radiation source increases and thermal damage may occur
Solution Approach 1:
The optical system acts as a mediator that redistributes light energy. By using asymmetric magnification with two anamorphic optics, the system concentrates light in specific directions (along-track and cross-track) rather than uniformly increasing overall intensity. This allows the sensor to receive sufficient light without requiring a proportionally higher power electromagnetic radiation source, thereby avoiding thermal damage to objects on the conveyor belt
Solution Approach 2:
The optical system applies local quality by directing magnification differently in different directions. The first anamorphic optic provides magnification in the along-track direction while the second provides magnification in the cross-track direction. This localized optical manipulation allows light energy to be concentrated where needed without uniformly increasing the overall intensity of electromagnetic radiation, thus avoiding thermal damage while maintaining signal magnitude
3Measurement precision
If an optical system with high magnification is used to improve resolution, then the spatial resolution is improved, but the cross-track magnification may increase distortion and reduce imaging accuracy
Solution Approach 1:
The optical system segments the magnification function into two separate anamorphic optics, each responsible for magnification in a specific direction. The first anamorphic optic handles along-track magnification while the second handles cross-track magnification. This segmentation allows independent optimization of magnification in each direction, enabling high resolution along the scan direction while minimizing distortion in the cross-track direction
Solution Approach 2:
The system employs asymmetric magnification where the degree of magnification differs between the along-track and cross-track directions. The first anamorphic optic provides stronger magnification in the along-track direction (perpendicular to the detector array) while the second anamorphic optic provides appropriate magnification in the cross-track direction (parallel to the detector array). This asymmetric design matches the linear detector geometry and minimizes geometric distortion while maximizing spatial resolution
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 enhances the line-scan imager's ability to resolve smaller objects with improved efficiency and accuracy, reducing thermal damage risks by optimizing light focus and distribution, allowing for higher line-scan frequencies without compromising spatial resolution or object integrity.
Implementation Method 1
a first anamorphic optic with a first focal length and a first focal line, where the first anamorphic optic is configured such that the first focal line is about parallel to a cross track direction
Implementation Method 2
a second anamorphic optic with a second focal length and a second focal line, where the second focal length is different than the first first focal length. The second anamorphic optic is positioned such that the first focal line and the second focal line are in about the same location
Implementation Method 3
Optical systems may be used to focus or otherwise manipulate the light or electromagnetic radiation before entry into the line scan imager
Data Source
AI summary
Optical systems are provided. In an embodiment, the optical system includes a first anamorphic optic having a first focal length and a first focal line, where the first focal line is parallel to a cross track direction. A second anamorphic optic has a second focal length and a second focal line, where the second focal length is different than the first first focal length. The second anamorphic optic is positioned such that the first focal line and the second focal line are in about the same location. The first and second anamorphic optics are aligned along an optical signal path, and are configured to provide afocal magnification to a signal beam along an along track direction to produce a magnified beam. A line scan imager includes an objective lens and a linear detector, and the second anamorphic optic is configured to direct the magnified beam at the objective lens.