Waveguide Diffraction Grating for Night Vision Image Overlay
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing optical devices, such as night vision goggles and telescopic sights, struggle to effectively combine and differentiate between images from different sources, like thermal cameras and visible light, often requiring bespoke optics or resulting in images with limited contrast and color range, making it difficult for viewers to distinguish between them, and these solutions are not easily adaptable for retrofitting.
Innovation Solution
A digital image overlay system using an image intensified night vision or telescopic sight device, a second imaging device, and a waveguide with diffraction gratings to combine and overlay images from different sources, allowing for contrasting color content and easy retrofitting by using a collimator and waveguide assembly that can be clipped onto existing devices.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If digital thermal image is injected via collimation optic into I2 objective optic, then the digital thermal image can be combined with the I2 image, but both images must be the same color (F phosphor color) resulting in poor contrast and difficulty in differentiation
Solution Approach 1:
The patent introduces a waveguide as an intermediary optical component that receives the I2 image and digitally overlays the thermal image with contrasting colors. The waveguide acts as a mediator between the I2 optic and the thermal image source, allowing color differentiation while maintaining image combination. This resolves the contradiction by enabling both image combination and color contrast through the intermediary waveguide structure.
2Adaptability or versatility
If thermal or symbology digital image is overlaid onto existing telescopic sight, then the digital image can be combined with the telescopic image, but it requires either partial obscuration of the front aperture or considerable redesign of the eyepiece optic
Solution Approach 1:
The patent segments the optical system into distinct functional modules: the existing telescopic sight, a separate waveguide assembly with diffraction gratings, and a digital image source. This segmentation allows the overlay capability to be added without redesigning the entire telescopic sight, as each component operates independently. The waveguide assembly can be retrofitted as a separate unit, resolving the contradiction between image overlay capability and device complexity.
Solution Approach 2:
The waveguide serves as an intermediary that bridges the telescopic sight and the digital image source. It receives light from the telescopic sight through one surface and overlays the digital image through diffraction gratings on its surfaces, enabling combination without modifying the original telescopic sight design. This intermediary approach eliminates the need for aperture obscuration or eyepiece redesign.
3Ease of manufacture
If bespoke optics are used to combine images from different sources, then the images can be combined, but the solution is not adaptable for retrofitting to existing devices
Solution Approach 1:
The waveguide assembly is designed as a universal component that can be retrofitted to multiple different optical devices (I2 devices, telescopic sights, etc.). It performs multiple functions: receiving light from the primary device, overlaying digital images with contrasting colors, and maintaining the primary device's original functionality. This universal design enables both high-quality image combination and easy retrofitting, resolving the contradiction between manufacturing quality and adaptability.
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 clear differentiation between combined images with contrasting colors, improving visibility and adaptability by maintaining image size and magnification, allowing viewers to easily distinguish between different image types without obscuring the field of view or requiring significant redesign.
Implementation Method 1
The waveguide has a first diffraction grating configured to receive the first image, a second diffraction grating configured to receive the second image, and a guide portion disposed between the first diffraction grating and the second diffraction grating configured to convey the second image to the first grating. The first diffraction grating is configured to overlay the first image and the second image.
Data Source
AI summary
An optical system for overlaying a first image of a scene and a second image includes an image intensified night vision and/or telescopic device providing the first image, a second imaging device with an image display and collimation optics providing the second image, and a waveguide. The waveguide has a first diffraction grating configured to receive the first image, a second diffraction grating configured to receive the second image, and a guide portion disposed between the first diffraction grating and the second diffraction grating configured to convey the second image to the first grating. The first diffraction grating is configured to overlay the first image and the second image.