KEYENCE XG-8000 Line Scan Visual Debugging Guide

2.3 Light source connection and voltage selection

The CA-DC21E lighting expansion unit provides two LED output ports (LIGHT 1, LIGHT 2). Maximum load of output terminal: 24 V DC or 12 V DC, selected through the DIP switch (8-bit) on the right side of the unit:

Position 1-4 controls LIGHT 1 (all OFF=12V, all ON=24V)

Position 5-8 controls LIGHT 2 (all OFF=12V, all ON=24V)

Danger warning: If a 12V light is connected to a 24V output, it will immediately burn out and may cause a fire. The default voltage at the factory is 12V. Before making any changes, be sure to check the lamp nameplate.

The IN terminal block provides a forced light off input (LOFF), and when the terminal is ON, all LED outputs are turned off, which can be used for safety interlocking.

Image acquisition mode and parameter calculation

The line scan camera has two core acquisition modes: "Fixed" and "Continuous".

3.1 Fixed frame mode (suitable for shooting a rectangular image with a single trigger)

Used for detecting workpieces with limited length, collect one frame (consisting of N rows) per trigger.

Key parameters:

Shutter Speed: Exposure time per line (μ s). It must be at least 3 μ s smaller than the Line Trigger Cycle.

Number of Lines: Frame height (number of lines). Calculation formula:

Rows=vertical field of view (mm)/horizontal pixel resolution (mm/pixel)

For example, with a 2048 pixel camera and a horizontal field of view of 150 mm, the resolution is 0.073 mm/pixel. To shoot a 100mm long workpiece, 100/0.073 ≈ 1370 lines are required.

Line Trigger Cycle: The time interval (μ s/line) between two adjacent lines of data collection, determined by the speed of object movement

Cycle (μ s)=(vertical movement time (μ s))/number of rows

Movement time=Vertical field of view length (mm)/Movement speed (mm/s).

For example, if the speed is 200 mm/s, the vertical length is 100 mm, and the movement time is 0.5 s=500000 μ s, then the period is approximately 500000/1370 ≈ 365 μ s/line.

Trigger method:

Timed trigger: Select "Method"="Time" in Capture Options and trigger internally according to the set cycle.

Encoder trigger: Select "Encoder" and trigger each line of acquisition through external pulses. The unit of Line trigger cycle needs to be set in "Parameters" as the number of pulses per line. For example, if the total number of pulses for the workpiece is 4110 and 1370 rows are required, then set 3 pulses per row.

3.2 Continuous mode (suitable for infinite length material detection)

The camera continues to capture, and the image buffer adopts a "overlay" mode. Additional Overlapping Lines need to be set to create overlapping areas between adjacent frames to avoid frame loss.

Note: The continuous mode forces the number of image buffers to be set to 3, and the operation type is' overwrite '. If the original settings do not match, the system will automatically make changes.

3.3 Correction of vertical stretching/compression of images

If the displayed image is stretched or flattened in the vertical direction, it indicates that the Line Trigger Cycle does not match the actual motion speed:

The image is stretched downwards → the triggering period of the row is too large → the period value should be reduced.

Image compression upwards → line trigger cycle too small → cycle value should be increased.

When adjusting, you can simultaneously observe the Brightness and Sharpness LED indicators on the back of the camera. Default threshold: Brightness LEDs 1/2/3 correspond to maximum grayscale values of 64/128/192 respectively; The sharpness LED corresponds to a maximum differential value of 10/20/30.

Lens selection and working distance determination

The XG-HL02M/04M uses a C-mount lens (such as the CA-LHW series), while the XG-HL08M uses an M40 P0.75 special interface lens (such as the CA-LHL series).

Check FOV chart: Taking CA-LHW16 (16mm lens) as an example, if a horizontal field of view of 200mm is required, the chart should display a working distance (WD) of 200mm and a 0.5mm extension ring should be added.

Note:

Ordinary C-mount lenses (non CA-LHW) may not be able to cover the wide image plane of line scan cameras, resulting in dark corners at the edges.

When using macro lenses (CA-LM0210, CA-LML0210), the lens must be directly fixed to the device using a dedicated mounting bracket (OP-87337), otherwise the weight of the lens may damage the camera interface.

Lighting Technology and Shadow Correction

5.1 Selection of Lighting Modes

Mirror reflection: used to detect dents, scratches (scattered light, defects in dark areas) on flat surfaces.

Diffuse reflection: used to detect protrusions and burrs (light directly reflects back to the camera, bright areas display defects).

Transmitting illumination: used for foreign object detection on transparent/semi transparent films, where foreign objects obstruct light and present dark spots.

5.2 Shading Correction

When the brightness within the field of view is uneven (such as dark edges and bright centers), shadow correction must be performed.

Operation steps:

Open the Linescan Calibration tool in Flow Editor.