Optical Diamond Passband Filtering for Low-Power Anti-Aliasing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Digital light projection systems face challenges with computational burden and power drain due to the digital implementation of finite impulse response (FIR) filters for noise and aliasing mitigation.
Innovation Solution
Implementing an optical-domain filter using a spatial light modulator with a two-dimensional array of pixels, where the image is spatially repositioned over a plurality of positions during a frame period, with each position maintained for a time period determined by non-negative coefficients of a filter transfer function.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If digital FIR filter is implemented through software or hardware, then noise and aliasing are mitigated, but computational burden and power drain increase
Solution Approach 1:
The patent replaces the digital computational system (software/GPU/hardware logic gates) with an optical system using a spatial light modulator. The FIR filtering operation is performed optically by spatially repositioning the image across multiple pixel positions during a frame period, where each position corresponds to a coefficient in the filter transfer function. This substitution eliminates the computational burden and power consumption of digital multiplication and addition operations while achieving the same noise and aliasing mitigation through optical domain processing.
2Object-affected harmful factors
If digital FIR filter is implemented through software or hardware, then noise and aliasing are mitigated, but computational complexity increases
Solution Approach 1:
The patent substitutes complex digital computational operations with a simpler optical manipulation process. Instead of performing multiplication and addition operations for each pixel through software or hardware logic, the system uses a spatial light modulator to physically reposition the image across different pixel locations during the frame period. The temporal fusion property of human vision integrates these repositioned images to produce the filtered output, dramatically reducing computational complexity while maintaining filtering effectiveness.
Solution Approach 2:
The patent employs periodic action by repositioning the image across multiple positions during each frame period. The image is displayed at different spatial locations corresponding to different coefficients of the filter transfer function, with each position maintained for a specific time period. This periodic spatial repositioning within the frame period enables the optical implementation of the FIR filter, where the temporal integration of these periodic positions produces the final filtered image, replacing complex digital computations with a time-multiplexed optical process.
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 reduces the computational burden associated with digital FIR filters by leveraging time multiplexing and the temporal fusion property of human vision, effectively mitigating noise and aliasing while minimizing power consumption.
Implementation Method 1
leveraging time multiplexing and the temporal fusion property of human vision
Data Source
AI summary
Methods and apparatus for optical filtering. In one example, a device includes a spatial light modulator having a two-dimensional array of square, rectangular, or diamond pixels, and a controller coupled to the spatial light modulator. The controller can be configured to write image data representing an image to the spatial light modulator to control the spatial light modulator to display the image for a frame period, and during the frame period, spatially reposition the image on the array of pixels over a plurality of positions, each individual position of the plurality of positions being maintained for a respective time period, wherein the respective time period is selected according to one or more non-negative coefficients of an anti-aliasing filter transfer function.