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E-mail
wulihua@cinv.cn
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Phone
18019703828
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Address
Room 301, Building A, No. 2250 Pudong South Road, Pudong New Area, Shanghai
Shanghai Xinu Optical Technology Co., Ltd
Calibration and maintenance of industrial high-speed cameras
Date: 2025-10-16Read: 22
1、 Calibration of industrial high-speed cameras: the core step to ensure detection accuracy
Calibration should revolve around three dimensions: geometric accuracy, imaging quality, and frame rate accuracy. It is recommended to perform calibration every 3-6 months or immediately after changing lenses or moving devices.
1. Geometric accuracy calibration: solving the problem of "measurement deviation"
Core objective: To correct the correspondence between pixels and actual physical dimensions, and eliminate the influence of lens distortion.
Calibration tools: standard calibration board (such as checkerboard calibration board, accuracy ≥ 0.01mm), tripod (fixed camera and calibration board position).
Operation steps:
Fix the camera and calibration board, ensuring that the calibration board plane is parallel to the camera lens and the distance is consistent with the actual detection scene (such as detecting 10mm parts, set the calibration distance to 50cm);
Take 3-5 images of the calibration board from different angles (rotation angle ≤ 15 °, covering the edge of the camera field of view);
Import visual software (such as Halcon, VisionPro), run calibration algorithms, and automatically calculate the "pixel equivalent" (such as 1 pixel=0.02mm) and lens distortion coefficient;
Verification: Use a standard component of known size (such as a 10mm × 5mm rectangular block) to take photos for testing. If the measurement error is ≤± 0.03mm, the calibration is qualified.
2. Imaging quality calibration: solving the problem of "image quality distortion"
Brightness and contrast calibration:
Shoot standard grayscale cards (16 or 24 levels) to ensure that the software can clearly distinguish each level of grayscale, without "overexposure" (pure white blocks without details) or "underexposure" (pure black blocks without layers);
If the grayscale resolution is incomplete, adjust the camera's "exposure time" (≤ 100 μ s for high-speed scenes to avoid motion blur) and "gain" (≤ 20dB to reduce noise) until the grayscale level recognition is complete.
Color calibration (applicable to color cameras):
Shoot standard color cards (such as 24 color cards), and the software automatically compares the deviation between the actual color value and the standard color value;
If the deviation exceeds 10%, adjust the "white balance" (select "manual white balance" and calibrate with a white standard plate) and "color gamut range" through camera software to ensure accurate color reproduction.
3. Frame rate accuracy calibration: solving the problem of "capture lag"
Calibration tools: high-speed strobe light (frequency known, such as 1000Hz), timer.
Operation steps:
Let the strobe light flash at a fixed frequency and the camera shoot at the set frame rate (such as 1000fps);
Count the number of flashes of the strobe light in the image captured within 1 second. If the deviation between the number of flashes and the strobe light frequency is ≤ 2% (such as 980-1020 counts for a 1000Hz strobe light), the frame rate is qualified;
If the deviation exceeds 2%, check the camera power supply (ensure stable voltage, such as 12V ± 0.5V) and interface transmission (GigE interface requires CAT6 Ethernet cable), or contact the manufacturer to calibrate the firmware.
2、 Maintenance of industrial high-speed cameras: key measures to extend equipment lifespan
1. Daily maintenance (daily/weekly): preventive protection
Lens cleaning:
Blow off the floating dust on the surface of the lens with a balloon (avoid blowing with your mouth to prevent saliva contamination);
If there are oil stains or fingerprints, dip the lens paper into a specialized lens cleaner (such as Zeiss lens cleaner) and wipe it in a "spiral" shape from the center of the lens outward to avoid scratches caused by back and forth friction.
Body and interface inspection:
Check the camera casing daily for any damage and blockage of the heat dissipation holes (use a soft bristled brush to clean dust and prevent overheating and system crashes);
Plug and unplug data interfaces (such as GigE and USB 3.0) weekly, clean the interface pins with alcohol swabs to prevent oxidation and poor contact.
2. Regular maintenance (every 3-6 months): Deep maintenance
Sensor cleaning:
Turn off the camera power, remove the lens, use a sensor cleaning stick (adapted to the camera sensor size, such as APS-C format) dipped in a small amount of sensor cleaner, and gently wipe the sensor surface;
After cleaning, install the lens and shoot a pure white background. If there are no "black spots" (dust residue), the cleaning is qualified (it is recommended to be operated by professionals to avoid scratching the sensor).
Inspection of cables and fixed components:
Check whether the data cable is damaged or aged (such as cracked outer skin of the cable), and replace it immediately if necessary (priority should be given to using original cables to avoid transmission rate attenuation);
Check if the camera mounting bracket is loose and reinforce the screws with a wrench (especially in vibration scenarios such as near machine tools, anti loosening washers need to be added).
3. Long term maintenance (annually): systematic overhaul
Internal component inspection:
Contact the manufacturer or third-party testing agency to check if there are any bad pixels in the camera sensor (for capturing pure black images, if the number of single bad pixels is ≤ 5, it does not affect use; if it exceeds 10, the sensor needs to be replaced);
Check the cooling system (such as fans). If the fan speed is lower than the rated value (such as rated 3000rpm, but actually below 2500rpm), replace the fan to prevent high temperature from causing sensor performance degradation.
Software and firmware updates:
Upgrade the camera driver and supporting software to the latest version, fix known bugs (such as data transmission packet loss and unstable frame rate);
Backup camera parameter configurations (such as exposure time, gain, pixel equivalent) to avoid parameter loss after updates.
3、 Common problems and solutions
| Problem phenomenon | Possible reasons | Treatment measures |
| The image has impurities/Stripes | 1. The gain is too high; 2. Electromagnetic interference; 3. Sensor contamination | 1. Reduce the gain to ≤ 15dB; 2. Add a shielding layer to the camera cable to keep it away from interference sources such as motors; 3. Clean the sensor |
| Data transmission packet loss | 1. The cable specifications do not match (such as using CAT5 Ethernet cables for GigE); 2. Network congestion; 3. Loose interface | 1. Replace with CAT6 or above Ethernet cables; 2. Reduce the number of devices in the same network; 3. Re plug and unplug the interface and reinforce it |
| The camera cannot start | 1. Power supply failure; 2. Firmware damage; 3. Hardware malfunction | 1. Check the output voltage of the power adapter and replace it with an adapter of the same specification; 2. Use manufacturer's tools to restore firmware; 3. Contact after-sales maintenance |
| The measurement result has a large deviation | 1. Failure to calibrate in a timely manner; 2. Lens distortion; 3. Offset of calibration board position | 1. Perform geometric accuracy calibration again; 2. Replace low distortion lenses (such as industrial fixed focus lenses, distortion rate ≤ 0.1%); 3. Fix the calibration board and camera position |