High-precision metal-framed dot-pattern film the preferred choice for large-format transmissive calibration.

The metal-framed tensioned dot-pattern film is an optical calibration device consisting of a film sheet featuring a high-precision dot array pattern, secured to a metal frame using a high-flatness tensioning process; it is primarily used in machine vision, camera calibration, and 3D reconstruction systems.
1. Product Overview
(1) Flat Mounting on Metal Frame
① Utilizes a high-strength aluminum alloy or stainless steel frame, with the film secured flat via physical tensioning or a high-precision bonding process.
② Function: Completely eliminates issues such as film wrinkling or warping, ensuring the geometric flatness of the calibration plane in 3D space.
(2) Dot Pattern
① Unlike checkerboard patterns (which rely on corner detection), dot patterns utilize the extracted centers of the dots (via centroid algorithms) as calibration points.
② Advantages: Centroid extraction algorithms are insensitive to local blurring, noise, and edge distortion, offering superior positioning accuracy at the edges of the field of view or in the presence of significant lens distortion. Common types include regular dot arrays and asymmetric dot arrays.
(3) Film Substrate
① High-resolution optical exposure technology is used to create dot arrays with sharp edges and high black-and-white contrast on a PET film substrate.
② Features high light transmission and strong contrast, making it particularly suitable for use with backlighting (transmitted light).
2. Key Features and Advantages

3. Typical Application Scenarios

(1) Camera Distortion Correction and Calibration: Precise calibration of intrinsic and extrinsic parameters for industrial cameras (2D/3D) and binocular vision systems.

(2) 3D Measurement and Scanning Equipment: System geometric calibration for structured-light 3D scanners and laser scanners.

(3) Backlight Inspection and Optical Testing: Analysis of optical lens resolution, distortion, and transmittance in conjunction with a transmissive light box.

(4) Automated Positioning and Alignment: Setting reference points for vision-guided systems in pick-and-place machines and robotic arms.