I. Core Mechanism/Imaging Principle of Holographic Fan
1. The holographic fan fundamentally employs POV visual persistence imaging technology rather than traditional optical holographic projection. Its core logic is as follows:
2. Hardware Structure: The device features 2–4–8 high-density RGB-LED strips mounted on high-speed rotating blades, with an integrated main control chip that manages the sequential lighting and color switching of the LEDs.
3. Principle of visual persistence: The human retina retains an image residual for 1/24 to 1/16 of a second. The fan rotates at high speed (1800–3000 revolutions per minute), while the light strip sequentially illuminates image slices from different angles.
4. Imaging Logic: The video frame is decomposed by the system into vertical pixel slices, which are refreshed synchronously as the fan blades rotate; consecutive optical segments are synthesized by the human eye to create a floating, naked-eye 3D dynamic image, with the background automatically becoming "transparent" and the subject appearing suspended.
5. Motion synchronization requirements: The video frame rate and image motion speed must be precisely synchronized with the fan speed; otherwise, image jitter, tearing, ghosting, or double images may occur.
II. Recommended video format (file format + encoding + parameters)
1. Preferred format: Video format: MP4 (H.264 encoding), offering the highest compatibility as all holographic fans support it without decoding failures or playback lag.
2. Alternative formats: MOV (H.264/ProRes), AVI (uncompressed), suitable for high-definition, detailed content; 3. Use of MKV, RMVB, FLV, and WMV is prohibited as most devices are incompatible with these formats.
4. Image format: Static materials can use PNG (with transparent channels) or JPG; GIF animations tend to lag and are not recommended.
5. Key export parameters: Frame rate: 30fps (optimal); smaller fans support 25fps; 60fps is prohibited (speed mismatch may cause tearing); maintain consistent frame rate throughout – no speed adjustment allowed.
6. Bitrate: 10–20 Mbps, balancing clarity and file size to prevent image blur at low bitrates and upload failures at high bitrates.
7. Color mode: RGB 8-bit; CMYK disabled; anti-aliasing turned off to prevent white edges and blurring on subject contours.
9. File size: Single video ≤200 MB; recommended loop duration for videos: 10–30 seconds to avoid excessive lag.
III. Recommended aspect ratio and resolution (strictly matched to fan dimensions)
The holographic fan features a circular rotating imaging area with a vertical circular display. A square aspect ratio is recommended; the 16:9 landscape format is prohibited as it results in cropping and black borders.
1. General Standards: Aspect Ratio: 1:1 (square format, optimal), fully compatible with rotated circular frames without black borders or cropping; Alternative: 9:16 (vertical format), suitable for elongated portraits or product displays.
2. Recommended resolution: 1080×1080px for small fans (50 cm or smaller); 1440×1440px or 1920×1920px for large fans (60 cm or larger).
3. Prohibited aspect ratios: 16:9 and 4:3 landscape orientations; uploaded content will be severely cropped or displayed incompletely.
4. The holographic wall's splicing ratio matches the video aspect ratio.
5. Dimensional specifications: The main subject should be centered with 5% top and bottom margins to prevent edge clipping during rotation; text, logos, and core graphics must occupy at least 70% of the central area for clear 360° visibility; images must not be stretched or distorted and must strictly maintain a 1:1 square aspect ratio.
IV. Background Color Specifications (Determines the floating effect; Core Requirements)
1. Mandatory standard specifications: Pure black background: RGB (0,0,0), hexadecimal #000000; the background must be pure black—graduated black, gray, or textured black are prohibited. Principle: The holographic fan illuminates only non-black pixels in the video, while black pixels correspond to extinguished LEDs, automatically creating a holographic effect with a transparent background and the subject appearing suspended in mid-air. If the background is not pure black, gray shadows will appear, compromising the floating effect.
2. Disabled Background & Precautions
Prohibited backgrounds: white, colored, gradient, blurred, or textured backgrounds will result in cluttered visuals and lack of depth. For 3D materials, prioritize the Alpha transparency channel; during export, apply a pure black background. Ensure no residual gray or white edges on the subject; the image must be perfectly cropped.
V. Video Content Motion Standards (Adapted for Rotational Imaging to Avoid Residual Images)
Given the high-speed rotation characteristics of fans, content movement must adhere to the following rules to ensure smoothness: -Movement speed: Image rotation, displacement, and scaling should be smooth and uniform; rapid shaking, abrupt cuts, or quick zooming are prohibited. Excessive fan rotation can cause trailing or ghosting effects. -Video cycling: The first and last frames must be identical to achieve seamless playback without interruptions or lag. -3D content: Model rotation speed should not exceed 15°/second; rapid 360° rotations are avoided. -Text/LOGO: Rapid flashing or strobe animations are prohibited, as high-frequency LED refresh rates can cause visual fatigue and residual images.
VI. Upload and Testing Specifications
1. After exporting the video, play it in a media player to verify no black bars, noise, lag, or motion blur; copy it to the device's SD card or upload via WiFi. Use a file name composed solely of English letters and numbers—no special characters permitted. For initial playback adjustments: reduce the video speed if ghosting occurs; set a uniform frame rate of 30fps if画面 tearing is observed.