diff --git a/MainWindowViewModel.cs b/MainWindowViewModel.cs
index 54cb469..cd80745 100644
--- a/MainWindowViewModel.cs
+++ b/MainWindowViewModel.cs
@@ -1935,20 +1935,30 @@ M30";
             if (points.Count < 4)
                 return;
 
-            double topY = points.Max(point => point.Y);
-            double bottomY = points.Min(point => point.Y);
+            double minY = points.Min(point => point.Y);
+            double maxY = points.Max(point => point.Y);
 
-            var topRowPoints = points.Where(point => Math.Abs(point.Y - topY) < 0.0001).ToList();
-            var bottomRowPoints = points.Where(point => Math.Abs(point.Y - bottomY) < 0.0001).ToList();
+            // X间距：取最上排和最下排点的X极值，过滤侧面凸出的异常点
+            var edgePoints = points.Where(point => Math.Abs(point.Y - maxY) < 0.0001 || Math.Abs(point.Y - minY) < 0.0001).ToList();
+            double edgeMinX = edgePoints.Min(point => point.X);
+            double edgeMaxX = edgePoints.Max(point => point.X);
 
-            if (topRowPoints.Count < 2 || bottomRowPoints.Count < 2)
-                return;
+            double minX, maxX;
+            if (Math.Abs(edgeMaxX - edgeMinX) > 0.0001)
+            {
+                // 上下排有多于1个不同的X值，说明是矩形布局
+                minX = edgeMinX;
+                maxX = edgeMaxX;
+            }
+            else
+            {
+                // 上下排X全部相同（垂直排列），退回所有点的X极值
+                minX = points.Min(point => point.X);
+                maxX = points.Max(point => point.X);
+            }
 
-            double leftX = Math.Min(topRowPoints.Min(point => point.X), bottomRowPoints.Min(point => point.X));
-            double rightX = Math.Max(topRowPoints.Max(point => point.X), bottomRowPoints.Max(point => point.X));
-
-            Outer3175XSpacing = Math.Round(rightX - leftX, 3, MidpointRounding.AwayFromZero);
-            Outer3175YSpacing = Math.Round(topY - bottomY, 3, MidpointRounding.AwayFromZero);
+            Outer3175XSpacing = Math.Round(maxX - minX, 3, MidpointRounding.AwayFromZero);
+            Outer3175YSpacing = Math.Round(maxY - minY, 3, MidpointRounding.AwayFromZero);
             HasOuter3175Spacing = true;
 
             Debug.WriteLine($"[3.175外围孔] X间距={Outer3175XSpacing:F3}, Y间距={Outer3175YSpacing:F3}");