The ILDA Test Pattern
What the ILDA test pattern is, what its elements show, and where to find the official calibration procedure.
The ILDA test pattern is a standardized reference for evaluating scanner response at a specified point rate and scan angle.
What Is the ILDA Test Pattern?
The ILDA test pattern is a standardized frame containing:
- A circle that should touch all four sides of the inner square
- An inner square with anchor points at corners
- A diamond rotated 45°
- Calibration boxes in each corner
- Center crosshair
When rendered correctly on a properly calibrated scanner, the circle touches all four sides of the square with no overshoot or undershoot.
Why It Exists
The test pattern provides a common reference for scanner adjustment and comparison.
Qualified technicians can use it to:
- Compare scanner response at a stated rate and angle
- Check alignment, damping, gain, and blanking behavior
- Repeat the same diagnostic after servicing or setup changes
Loading the Test Pattern in BeamTracer
- Open the ILDA Viewer
- Find the TEST SUITE section in the left panel
- Click PATTERN
- The bundled test-pattern file (a single frame of 1,191 records) loads immediately
Reading the Results
Circle Touches Square Perfectly
At the stated point rate and scan angle, this is the target relationship described by the ILDA procedure.
Circle Bulges Past Square
The scanner response differs from the target. Gain, damping, point rate, scan angle, or their interaction may be involved.
Circle Doesn't Reach Square
The scanner response differs from the target. Diagnose it using the official procedure and the manufacturer's instructions.
Corners Are Rounded
This can reflect the scanner response or the test setup. The bundled test file itself is fixed, so do not infer a missing-point defect from the BeamTracer preview.
Previewing It in BeamTracer
BeamTracer shows the pattern's stored geometry and calculates required PPS as total records multiplied by FPS. Changing the FPS changes that calculation and the preview cadence; it does not test a physical scanner or discover its limit.
ILDA warns that careless scanner adjustment can damage scanners and that tuning should be performed by a knowledgeable person. Use the official ILDA test-pattern procedure together with the projector or scanner manufacturer's instructions.
Bundled Frame Record Count
BeamTracer's bundled pattern file contains 1,191 records in its single frame. That count lets you calculate its requested point rate at a chosen FPS; it does not guarantee compatibility with a particular scanner.