Geometry Grid & Alignment Test
Precision square grid with center crosshair, corner alignment marks, and concentric circles. Verifies that your display reproduces rectilinear geometry accurately without pincushion, barrel distortion, or curved panel stretching.
Technical Scope & Limitations
Browser fullscreen coordinates map to the active display window. Projectors and curved panels may exhibit optical distortions outside browser control.
Browser rendering output can be influenced by OS display scaling, GPU driver color settings, and active HDR profiles.
- Enter fullscreen mode.
- Check the grid lines: horizontal lines must be strictly parallel to top/bottom bezels; vertical lines parallel to side bezels.
- Verify the center circle: it must be perfectly circular, not stretched into an ellipse.
- Examine the corner boxes to confirm zero overscan cut-off.
What This Test Checks
- Rectilinear geometry: lines must be strictly parallel to monitor bezels.
- Concentric circle circularity: perfect circle test without elliptical warping.
- Square aspect ratio: width and height of grid cells must be strictly equal.
How to Perform the Test
- Enter fullscreen mode.
- Verify that the grid squares look identical across the entire width and height.
- Inspect the center circle: measure or visually verify that diameter is consistent in all directions.
What to Look For
- Barrel or pincushion distortion (curved grid lines) on projectors or CRT displays.
- Unequal horizontal vs vertical grid cell spacing indicating stretched resolutions.
Common Display Problems & Diagnostic Guidance
Curved Monitor Geometry
On curved gaming monitors (e.g. 1000R or 1500R), straight lines will physically follow the panel curve. When viewed from the center focal distance, the grid will appear perceptually square.
Frequently Asked Questions
Can flat LCD panels have geometry errors?
The physical LCD glass cannot warp, but GPU scaling settings (e.g. "Stretch to Full Screen") can stretch non-native resolutions into distorted non-square pixels.