Simply put, moiré pattern is a manifestation of the beat principle. Mathematically, when two equal‑amplitude sine waves with close frequencies are superimposed, the amplitude of the composite signal varies according to the difference between the two frequencies. The beat principle is widely applied in radio‑television and communications for frequency conversion, modulation and other operations. Likewise, the beat principle also applies to spatial frequency. When stripes with slightly different spatial frequencies are superimposed, their overlapping positions gradually shift due to differences in stripe spacing, which also produces beats. So how can we mitigate moiré patterns when they occur on a video‑conference camera? Today, the editor of Kaimorui will give you a detailed introduction.

The methods to reduce moiré patterns are listed below:

1. Adjust the camera angle: Moiré patterns arise from the angular relationship between the camera and the subject. Slightly rotating the camera can eliminate or alter existing moiré patterns.
2. Adjust the camera position: In addition, shifting the camera horizontally or vertically to modify the angular relationship can reduce moiré artifacts.
3. Adjust the focus: Over‑sharp focus and excessive fine details on intricate patterns may trigger moiré patterns. Slight defocusing changes image sharpness and helps suppress moiré effects.
4. Adjust the lens focal length: Use a different lens or modify the focal‑length setting to alter or eliminate moiré patterns.

That concludes today’s sharing. To eliminate moiré patterns, the lens resolution should be far lower than the spatial frequency of the photosensitive sensor. Under this condition, no stripes comparable to the sensor’s spatial frequency will appear in the image, and moiré patterns will not be generated.