Scrolling Spectral Filter With Rolling Shutter Synchronization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for capturing spectral and spatial information, such as static spectral imaging and linearly scrolling discrete filters, reduce spatial resolution and are limited by mechanical vibrations and long image acquisition times.
Innovation Solution
A device with a spinning filter wheel containing multiple filter segments captures images by sequentially exposing rows of pixels in a rolling shutter mode, allowing the filter wheel to scroll across the array without mechanical vibrations, thereby increasing spectral resolution without decreasing spatial resolution and enabling shorter image acquisition times.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If linearly scrolling discrete filters are used to capture spectral information, then spectral resolution is improved, but spatial resolution is reduced and mechanical vibrations occur
Solution Approach 1:
The patent applies the dynamics principle by transitioning from static discrete filters to a dynamically rotating filter wheel. The filter wheel rotates during image capture, allowing multiple filter segments to be positioned in front of the sensor array sequentially. This dynamic approach enables spectral differentiation without requiring physically larger filter assemblies, thereby maintaining spatial resolution while achieving spectral resolution through temporal multiplexing of the rotating filters.
Solution Approach 2:
The patent applies the dimensionality change principle by introducing the time dimension to the spectral imaging process. Instead of arranging filters spatially in a linear array that physically blocks parts of the sensor, the system uses a rotating filter wheel where filters are arranged circumferentially. The rotation adds a temporal dimension, allowing different spectral bands to be captured at different time instances, effectively converting a spatial problem into a temporal solution that preserves spatial resolution.
2Loss of information
If linearly scrolling discrete filters are used, then spectral information is captured, but image acquisition time is prolonged
Solution Approach 1:
The patent applies the continuity of useful action principle by implementing a rolling shutter readout mode that continuously captures image data from different rows of the sensor array as the filter wheel rotates. Instead of stopping to capture each spectral band sequentially with traditional methods, the system maintains continuous operation where the rolling shutter reads out rows synchronized with the filter wheel rotation, ensuring that spectral information is captured continuously without interruption, thereby reducing total acquisition time.
Solution Approach 2:
The patent applies the periodic action principle by synchronizing the rolling shutter readout with the periodic rotation of the filter wheel. The filter wheel rotates at a controlled speed, presenting different filter segments to the sensor array in a periodic manner. The rolling shutter is configured to read out rows at intervals that match the filter wheel rotation period, ensuring that each spectral band is captured at the optimal moment in the rotation cycle. This periodic synchronization enables efficient spectral capture without requiring prolonged exposure times.
3Stability of the object's composition
If filter wheel spins during image capture, then mechanical vibrations are eliminated, but synchronization precision is required
Solution Approach 1:
The patent applies the feedback principle by implementing a synchronization mechanism that monitors the filter wheel rotation and adjusts the rolling shutter readout timing accordingly. The system includes sensors or encoders that detect the position of the filter wheel and provide feedback signals to the control unit. Based on this feedback, the rolling shutter readout is precisely timed to capture data when the desired filter segment is in front of the sensor array, ensuring accurate spectral assignment even during rotation. This closed-loop feedback control maintains synchronization precision while allowing the filter wheel to spin freely without mechanical vibration constraints.
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 approach allows for high spectral resolution with maintained spatial resolution, supports up to 100 or more filter segments, and reduces image acquisition time compared to linearly scrolling assemblies, enabling high-definition imaging and video capture.
Implementation Method 1
An optical filter is a device that filters light, incident on the optical filter, based on wavelength. For example, a bandpass filter may transmit light in a particular range of wavelengths, while rejecting (e.g., absorbing or reflecting) light at wavelengths that fall outside of (e.g., above or below) the particular range of wavelengths.
Data Source
AI summary
A device including an array of pixels and a filter wheel may capture a plurality of images by exposing the array of pixels. The device may spin, while capturing the plurality of images, the filter wheel, and the filter wheel may include filter segments. In some implementations, a portion of the filter wheel in front of the array of pixels includes two or more filter segments.