Two-Sided DOE Camera Calibration for Single-Image Intrinsics
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional camera calibration methods for VR, AR, and MR technologies are time-consuming and cumbersome, especially when multiple cameras are involved, as they require capturing multiple images of a calibration grid and processing them to determine intrinsic parameters.
Innovation Solution
A two-sided diffractive optical element (DOE) with specific grating patterns on each surface is used to form a light pattern, allowing cameras to determine intrinsic parameters from a single image, reducing the brightness of the central intensity peak to a predetermined level and ensuring uniform brightness across other light sources.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional camera calibration methods are used for multiple cameras, then intrinsic parameters can be determined, but the calibration process becomes time-consuming and cumbersome
Solution Approach 1:
The patent combines multiple calibration targets into a single composite calibration target that can be captured in one image. This single target contains multiple patterns that allow simultaneous calibration of multiple cameras, eliminating the need to capture multiple separate images for each camera or each target, thus dramatically reducing calibration time while maintaining accuracy
Solution Approach 2:
The calibration target is pre-designed with specific geometric patterns and known dimensions that encode all necessary calibration information. The target includes pre-calculated patterns that will work with multiple cameras simultaneously, so when the image is captured, all intrinsic parameters can be extracted directly without requiring multiple captures or complex sequential processing
2Measurement precision
If multiple images of calibration grid are captured for calibration, then accurate intrinsic parameters can be obtained, but the calibration process becomes cumbersome and complex
Solution Approach 1:
The patent merges multiple calibration targets into a single composite target that contains all necessary calibration patterns. This single target can be used to calibrate multiple cameras simultaneously from a single captured image, eliminating the complexity of capturing and processing multiple separate images while maintaining the accuracy needed for intrinsic parameter determination
Solution Approach 2:
The composite calibration target is designed to serve multiple functions simultaneously: it can be used for calibrating multiple different cameras, it contains patterns that work for various calibration algorithms, and it provides reference points for both intrinsic and extrinsic parameter calibration all in one structure, thereby simplifying the overall calibration 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 enables fast and efficient intrinsic calibration of multiple cameras, reducing the brightness of the central intensity peak to 1.1±0.5% of the laser beam, facilitating accurate calibration without saturation or detection issues, and allowing simultaneous calibration of multiple cameras in AR/VR systems.
Implementation Method 1
a two-sided diffractive optical element (DOE) with specific grating patterns on each surface is used to form a light pattern
Data Source
Figure 1
Figure 2
Figure 3A
AI summary
Embodiments provide image display systems and methods for one or more camera calibration using a two-sided diffractive optical element (DOE). More specifically, embodiments are directed to determining intrinsic parameters of one or more cameras using a single image obtained using a two-sided DOE. The two-sided DOE has a first pattern on a first surface and a second pattern on a second surface. Each of the first and second patterns may be formed by repeating sub-patterns that are lined when tiled on each surface. The patterns on the two-sided DOE are formed such that the brightness of the central intensity peak on the image of the image pattern formed by the DOE is reduced to a predetermined amount.