Optical Axis Calibration Using Speckle Geometry Against Jig Tolerance

The patent replaces the mechanical jig-based alignment method with an optical calculation method. Instead of relying on the mechanical jig to physically align the speckle emission device with the reference plane, the system captures images of the reference plane, extracts feature points, and calculates the optical axis position through coordinate transformation and geometric computation. This substitution eliminates the direct dependency on mechanical jig precision.

The patent creates a digital copy of the reference plane by capturing its image and extracting feature points. The coordinate system of the reference plane is reproduced in the digital image space, allowing the optical axis position to be calculated in the image coordinate system and then transformed back to the physical coordinate system. This copying approach bypasses the need for precise mechanical contact between the jig and the reference plane.

The patent replaces the need for high-precision mechanical jigs with a computational image processing system. The complexity is shifted from mechanical manufacturing to software algorithms, where feature point extraction, coordinate transformation, and geometric calculation are performed digitally. This reduces mechanical manufacturing complexity while achieving high measurement precision.

The system uses the reference plane itself to provide the calibration information needed. By capturing the image of the reference plane and using its feature points for coordinate system establishment, the reference plane serves both as the object to be aligned with and as the source of calibration data, eliminating the need for separate high-precision jig components.

The patent creates a digital replica of the reference plane through image capture and feature point extraction. The coordinate relationships on the reference plane are copied into the image coordinate system, allowing accurate calculation of the optical axis position without physical contact. This digital copying maintains operational simplicity while eliminating jig tolerance errors.

The patent introduces an image coordinate system as an intermediary between the physical reference plane and the speckle emission device alignment. The feature points extracted from the reference plane image serve as intermediaries to establish the coordinate transformation relationship, enabling accurate optical axis positioning without direct mechanical contact between the jig and reference plane.