Color Night Vision Camera Using CMY Subtractive Filtering
Solution Overview
Problem
Existing night vision systems lack color information, leading to monochrome images that hinder situational awareness, and are often complex, costly, and cumbersome due to the need for multiple intensifiers and noise reduction techniques.
Innovation Solution
A color night vision system using a unique three-lens-filtering setup with subtractive Cyan, Magenta, and Yellow (CMY) color filters, reducing the number of intensifiers and implementing advanced noise reduction methods such as spatial and temporal integration, and non-local image denoising algorithms.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of information
If three input/output channels are used to represent the color spectrum, then color information is improved, but device complexity increases to six intensifiers
Solution Approach 1:
The patent combines multiple color channels into a single intensifier by using a color filter array (CFA) that patterns different color filters (red, green, blue) across the image sensor array. This allows one intensifier to handle multiple color channels simultaneously, reducing the total number of intensifiers from six to three while preserving color information through the CFA's spectral separation capabilities
2Loss of information
If a spinning wheel or mechanical apparatus is used to rapidly change color filters, then color information is improved, but cost and complexity increase
Solution Approach 1:
The patent replaces the mechanical spinning wheel color filter system with a static color filter array (CFA) patterned directly on the image sensor. This eliminates moving parts and mechanical complexity while maintaining color separation through the spatial distribution of different color filters across the sensor array, achieving color night vision without mechanical apparatus
3Loss of information
If multiple intensifiers are used to capture color spectrum, then color information is improved, but weight and bulk increase
Solution Approach 1:
The patent merges multiple color channel processing functions into fewer intensifiers by using a color filter array that enables a single intensifier to handle red, green, and blue channels through spatial filtering. This reduces the total number of intensifiers and associated components, thereby decreasing the overall weight and bulk of the night vision system while preserving color information
4Adaptability or versatility
If existing stereo monochrome and monocular color techniques are combined, then functionality is improved, but system complexity becomes impractical
Solution Approach 1:
The patent creates a universal image intensifier system with a color filter array that can perform multiple functions: it provides color separation for monocular color vision, supports stereo vision through binocular arrangement, and maintains compatibility with existing monochrome night vision techniques. This multi-functional design achieves stereo color functionality without requiring separate dedicated systems for each function, thereby reducing overall system complexity
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 effectively captures and preserves color information, reduces noise, and increases sensitivity, resulting in a more accurate and interpretable image in low-light conditions, while also being more portable and cost-effective.
Implementation Method 1
Each image intensifier tube assembly includes a lens, a color filter, an image intensifier, and a phosphor screen. The lens focuses light onto the image intensifier, which converts optical energy to electrical energy through the photoelectric effect.
Implementation Method 2
The image intensifier tube assembly includes a lens, a color filter, an image intensifier, and a phosphor screen. The phosphor screen converts electrical energy back to optical energy, producing visible light output.
Implementation Method 3
A color filter is placed over the image intensifier to transmit only specific wavelengths of light, separating color information while reducing the number of intensifiers needed.
Data Source
AI summary
Disclosed are improved methods, systems and devices for color night vision that reduce the number of intensifiers and/or decrease noise. In some embodiments, color night vision is provided in system in which multiple spectral bands are maintained, filtered separately, and then recombined in a unique three-lens-filtering setup. An illustrative four-camera night vision system is unique in that its first three cameras separately filter different bands using a subtractive Cyan, Magenta and Yellow (CMY) color filtering-process, while its fourth camera is used to sense either additional IR illuminators or a luminance channel to increase brightness. In some embodiments, the color night vision is implemented to distinguish details of an image in low light. The unique application of the three-lens subtractive CMY filtering allows for better photon scavenging and preservation of important color information.