Effect of each type of lighting
EYE+ XTD supports a frontlight via the frontlight connector and an additional light (e.g. a backlight) via the GPIO connector.
The type of lighting chosen may highlight certain specific areas of the part to be observed or detected. The table below gives the example of an object illuminated from two different angles: frontlight or external backlight.
Frontlight |
Backlight |
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|---|---|---|
Example of object illumination |
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Areas of the part illuminated (in yellow) |
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Rendering image |
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Polarizers
Additionally, the frontlight and the camera can be equipped with polarizers. This option can be useful for improving vision when dealing with reflective parts or backgrounds. Reflections can make vision tricky and difficult, reducing detection performance. In such cases, using polarized light can significantly improve results as visible in Table 25.
Reflective part |
|
|---|---|
No filter |
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Polarization filter |
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The frontlight and camera filters are linearly-polarized and must be mounted perpendicularly; for example, 0° on the lights and +90° on the lens. Adjustment is done on the polarized lens, which is designed for this type of setting.
We recommend performing this adjustment while in the Camera configuration wizard. Immediately after setting the focus, you can use the live image to adjust the polarized lens to eliminate reflections on your reflective parts.
Warning
Using polarized filters will reduce light intensity. A longer exposure time may be necessary.