diff --git a/core/res/res/values/dimens.xml b/core/res/res/values/dimens.xml
index 30ea7c1e18c49..181bdf249b409 100644
--- a/core/res/res/values/dimens.xml
+++ b/core/res/res/values/dimens.xml
@@ -414,6 +414,10 @@
      to 0 -->
      <dimen name="circular_display_mask_offset">0px</dimen>
 
+     <!-- Amount to reduce the size of the circular mask by (to compensate for aliasing
+     effects). This is only used on circular displays. -->
+     <dimen name="circular_display_mask_thickness">1px</dimen>
+
      <dimen name="lock_pattern_dot_line_width">3dp</dimen>
      <dimen name="lock_pattern_dot_size">12dp</dimen>
      <dimen name="lock_pattern_dot_size_activated">28dp</dimen>
diff --git a/core/res/res/values/symbols.xml b/core/res/res/values/symbols.xml
index 00d9954b83720..b8944e01d8472 100755
--- a/core/res/res/values/symbols.xml
+++ b/core/res/res/values/symbols.xml
@@ -420,6 +420,7 @@
   <java-symbol type="dimen" name="immersive_mode_cling_width" />
   <java-symbol type="dimen" name="circular_display_mask_offset" />
   <java-symbol type="dimen" name="accessibility_magnification_indicator_width" />
+  <java-symbol type="dimen" name="circular_display_mask_thickness" />
 
   <java-symbol type="string" name="add_account_button_label" />
   <java-symbol type="string" name="addToDictionary" />
diff --git a/services/core/java/com/android/server/wm/CircularDisplayMask.java b/services/core/java/com/android/server/wm/CircularDisplayMask.java
index 9fdfc47dfede8..7c2da2dc292e5 100644
--- a/services/core/java/com/android/server/wm/CircularDisplayMask.java
+++ b/services/core/java/com/android/server/wm/CircularDisplayMask.java
@@ -50,9 +50,10 @@ class CircularDisplayMask {
     private int mRotation;
     private boolean mVisible;
     private boolean mDimensionsUnequal = false;
+    private int mMaskThickness;
 
     public CircularDisplayMask(Display display, SurfaceSession session, int zOrder,
-            int screenOffset) {
+            int screenOffset, int maskThickness) {
         mScreenSize = new Point();
         display.getSize(mScreenSize);
         if (mScreenSize.x != mScreenSize.y) {
@@ -84,6 +85,7 @@ class CircularDisplayMask {
         mPaint.setAntiAlias(true);
         mPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.CLEAR));
         mScreenOffset = screenOffset;
+        mMaskThickness = maskThickness;
     }
 
     private void drawIfNeeded() {
@@ -121,8 +123,8 @@ class CircularDisplayMask {
         int circleRadius = mScreenSize.x / 2;
         c.drawColor(Color.BLACK);
 
-        // The radius is reduced by 1 to provide an anti aliasing effect on the display edges.
-        c.drawCircle(circleRadius, circleRadius, circleRadius - 1, mPaint);
+        // The radius is reduced by mMaskThickness to provide an anti aliasing effect on the display edges.
+        c.drawCircle(circleRadius, circleRadius, circleRadius - mMaskThickness, mPaint);
         mSurface.unlockCanvasAndPost(c);
     }
 
diff --git a/services/core/java/com/android/server/wm/WindowManagerService.java b/services/core/java/com/android/server/wm/WindowManagerService.java
index 833b6cf2e8cc0..0b97667f0221c 100644
--- a/services/core/java/com/android/server/wm/WindowManagerService.java
+++ b/services/core/java/com/android/server/wm/WindowManagerService.java
@@ -5965,13 +5965,15 @@ public class WindowManagerService extends IWindowManager.Stub
                     if (mCircularDisplayMask == null) {
                         int screenOffset = mContext.getResources().getDimensionPixelSize(
                                 com.android.internal.R.dimen.circular_display_mask_offset);
+                        int maskThickness = mContext.getResources().getDimensionPixelSize(
+                                com.android.internal.R.dimen.circular_display_mask_thickness);
 
                         mCircularDisplayMask = new CircularDisplayMask(
                                 getDefaultDisplayContentLocked().getDisplay(),
                                 mFxSession,
                                 mPolicy.windowTypeToLayerLw(
                                         WindowManager.LayoutParams.TYPE_POINTER)
-                                        * TYPE_LAYER_MULTIPLIER + 10, screenOffset);
+                                        * TYPE_LAYER_MULTIPLIER + 10, screenOffset, maskThickness);
                     }
                     mCircularDisplayMask.setVisibility(true);
                 } else if (mCircularDisplayMask != null) {