Application of glass disc inspection equipment in MLCC appearance inspection-Xianghongyu

1. Core stage: transparent turntable and wrap-around "wise eye"

Imagine a crystal-clear glass disc rotating at a uniform speed driven by a precision motor – this is the "heart stage" of MLCC inspection. The testing process begins from this:

1. Automatic feeding: The MLCC is precisely and single-layer tiled on the surface of the high-speed rotating glass disc by means of a vibrating disc or a robotic arm.

2. Dynamic Flow: The glass disc rotates smoothly, carrying the MLCC gliding through the inspection area like flowing water.

3. Multi-angle "gaze": Around the glass turntable (above, on the side, or even below), a "discerning array" of high-speed industrial cameras is set up.

4. Collaborative Capture: Each camera acts like a trained photographer, capturing accurately as the component flows to its better field of view.

5. Intelligent Adjudication: Powerful image processing software analyzes photos in real-time to determine whether there are cosmetic defects (cracks, chipping, chips, stains, defective electrodes, etc.) with sub-pixel accuracy.

6. Automatic sorting: According to the judgment results, the system directs the sorting agency to accurately divide the good and defective products.

This "rotating stage + surround shooting" mode cleverly solves the problem of multi-angle and high-efficiency detection of micro-components.

2. Camera setup: surround and scan, no dead angle scanning

The glass disc structure provides a natural advantage for camera mounting:

1. All-round encirclement network:

• Top camera group: Responsible for photographing electrodes, markings, and surface defects on the top surface of the component. Multiple cameras can be set to cover different areas or use high-resolution cameras with telecentric lenses to ensure overall clarity.

• Side camera group: Mounted on the side of the turntable, the lens axis is roughly horizontal or slightly tilted. They cling to the edge of the turntable like agents, specifically capturing the edges and electrodes on the side of the MLCC. Multiple side cameras are distributed in a circular shape, making it easy to achieve 360° scanning without dead ends.

• Bottom camera (optional): Thanks to the high light transmission of the glass disc, a camera can be set up under the turntable to capture the appearance of the underside of the component through the glass. One can cover the entire disk.

2. "Wait for the rabbit" trigger: The camera does not need to move the tracking element. The encoder provides real-time feedback on the turntable position, and the system calculates the optimal moment for each component to reach the center of each camera's field of view, automatically triggering the camera to take a photo. The components "fall into the trap" in motion, and the camera "waits for the rabbit" in place, which is extremely efficient.

3. Light magic: the optical convenience of a transparent stage

The transparent nature of glass discs opens the door to complex and sophisticated lighting solutions:

1. Bottom Lighting - A Tool for Transmission Imaging:

• Backlight: A uniform backlight (such as an LED surface light) can be installed over a large area under the glass disc. Light penetrates the glass plate and the MLCC itself (ceramics have some light transmission), forming a high-contrast contour image that is a means of detecting chipping, chipping, dimensions, foreign objects, and parts of the internal structure (such as misalignment between layers).

• Coaxial light (bottom): A specially designed coaxial light source can also be installed at the bottom, which reflects the glass disk and illuminates the bottom of the element vertically, which can clearly show the scratch, oxidation, pollution and other defects of the electrode on the bottom surface.

2. Top Lighting - Illuminates Surface Details:

• Ring/dome/coaxial light: Mounted around or inside the top camera, providing illumination from different angles and characteristics. ring light highlights edges and surface unevenness; Dome light provides shadowless uniform illumination; Coaxial light clearly shows surface scratches, pockmarks, and printed characters.

3. Sideways lighting - outlines the three-dimensional outline:

• Installing bar light, point light source, or small-angle ring light near the side camera, and irradiating the MLCC edge edge and side electrode from the side, can significantly enhance the imaging contrast of side edge chipping, electrode absence, staining and other defects.

The core lighting advantage of glass pans is their transparency:

• "Through-Stage" Lighting Freedom: The bottom light source can penetrate the glass disk and act on the component without hindrance, which is not possible with non-transparent vehicles.

• Pure optical path: The glass surface is smooth and flat, and it is not prone to stray reflections interfering with imaging (compared to some metal or plastic carriers).

• Multi-layer optical path superposition: It is easy to combine the top, bottom, and side light sources to design better lighting solutions for different inspection needs (surface, edge, contour, interior).

4. The power of rotation: the efficiency and stability of dynamic detection

The continuous rotation of the glass turntable is key to efficient inspection:

1. Uninterrupted Assembly Line: Components are inspected in motion, and the glass pan rotates at a uniform speed to provide a steady, continuous feed without pauses. This significantly increases the inspection speed (UPH - Inspection Quantity per Hour) and meets the needs of MLCC mass production.

2. Centrifugal Force Assisted Positioning: The small centrifugal force generated by the rotation helps the MLCC maintain a relatively stable attitude and tiling on the glass plate (especially when combined with appropriate surface treatment or airflow assistance), reducing false positives caused by component jitter or overlap.

3. Uniform wear and easy cleaning: The glass surface is hard and smooth, and the wear resistance is good. Its non-static adsorption properties (or by coating) reduce dust adsorption, and it is very easy to clean and maintain (wipe or auto-clean), ensuring long-term stable image quality.

4. Open space: The rotating disk structure is open, which is convenient for engineers to debug equipment, clean and maintain, and adjust the light source and camera.

Conclusion: The "Rotating Guardian" of precision manufacturing

The glass disc inspection equipment, with its crystal clear rotating stage, surrounded "golden eye" army and unique multi-layer lighting convenience, has built an efficient, accurate and stable solution for the "appearance" of MLCC. It allows the tiny components of high-speed flow to be clearly "gazed at" in motion, so that hidden flaws have nowhere to hide. In the world of electronic components that pursue reliability, this rotating "transparent guardian" is continuously improving the quality of each MLCC and silently guarding the stable operation of modern electronic devices.