diff --git a/packages/SystemUI/animation/src/com/android/systemui/animation/Interpolators.java b/packages/SystemUI/animation/src/com/android/systemui/animation/Interpolators.java
index 58cef31aaf770..0a052df43ead3 100644
--- a/packages/SystemUI/animation/src/com/android/systemui/animation/Interpolators.java
+++ b/packages/SystemUI/animation/src/com/android/systemui/animation/Interpolators.java
@@ -70,4 +70,17 @@ public class Interpolators {
      */
     public static final Interpolator TOUCH_RESPONSE_REVERSE =
             new PathInterpolator(0.9f, 0f, 0.7f, 1f);
+
+    /**
+     * Interpolate alpha for notifications background scrim during shade expansion.
+     * @param fraction Shade expansion fraction
+     */
+    public static float getNotificationScrimAlpha(float fraction) {
+        fraction = fraction * 1.2f - 0.2f;
+        if (fraction <= 0) {
+            return 0;
+        } else {
+            return (float) (1f - 0.5f * (1f - Math.cos(3.14159f * Math.pow(1f - fraction, 2f))));
+        }
+    }
 }
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/NotificationShelf.java b/packages/SystemUI/src/com/android/systemui/statusbar/NotificationShelf.java
index 8f462fea04680..e49ca13fa25c8 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/NotificationShelf.java
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/NotificationShelf.java
@@ -31,6 +31,7 @@ import android.view.WindowInsets;
 import android.view.accessibility.AccessibilityNodeInfo;
 
 import com.android.internal.annotations.VisibleForTesting;
+import com.android.systemui.animation.Interpolators;
 import com.android.systemui.R;
 import com.android.systemui.plugins.statusbar.StatusBarStateController.StateListener;
 import com.android.systemui.statusbar.notification.NotificationUtils;
@@ -176,7 +177,13 @@ public class NotificationShelf extends ActivatableNotificationView implements
             viewState.height = getIntrinsicHeight();
             viewState.zTranslation = ambientState.getBaseZHeight();
             viewState.clipTopAmount = 0;
-            viewState.alpha = 1f - ambientState.getHideAmount();
+
+            if (ambientState.isExpansionChanging() && !ambientState.isOnKeyguard()) {
+                viewState.alpha = Interpolators.getNotificationScrimAlpha(
+                        ambientState.getExpansionFraction());
+            } else {
+                viewState.alpha = 1f - ambientState.getHideAmount();
+            }
             viewState.belowSpeedBump = mHostLayoutController.getSpeedBumpIndex() == 0;
             viewState.hideSensitive = false;
             viewState.xTranslation = getTranslationX();
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/notification/stack/StackScrollAlgorithm.java b/packages/SystemUI/src/com/android/systemui/statusbar/notification/stack/StackScrollAlgorithm.java
index 413048d6ce54e..d94d030f326e2 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/notification/stack/StackScrollAlgorithm.java
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/notification/stack/StackScrollAlgorithm.java
@@ -24,6 +24,7 @@ import android.util.MathUtils;
 import android.view.View;
 import android.view.ViewGroup;
 
+import com.android.systemui.animation.Interpolators;
 import com.android.systemui.R;
 import com.android.systemui.statusbar.NotificationShelf;
 import com.android.systemui.statusbar.notification.dagger.SilentHeader;
@@ -374,7 +375,13 @@ public class StackScrollAlgorithm {
         ExpandableView view = algorithmState.visibleChildren.get(i);
         ExpandableViewState viewState = view.getViewState();
         viewState.location = ExpandableViewState.LOCATION_UNKNOWN;
-        viewState.alpha = 1f - ambientState.getHideAmount();
+
+        if (ambientState.isExpansionChanging() && !ambientState.isOnKeyguard()) {
+            viewState.alpha = Interpolators.getNotificationScrimAlpha(
+                    ambientState.getExpansionFraction());
+        } else {
+            viewState.alpha = 1f - ambientState.getHideAmount();
+        }
 
         if (view.mustStayOnScreen() && viewState.yTranslation >= 0) {
             // Even if we're not scrolled away we're in view and we're also not in the
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/phone/ScrimController.java b/packages/SystemUI/src/com/android/systemui/statusbar/phone/ScrimController.java
index a952db2a60733..c34fa2f049e1c 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/phone/ScrimController.java
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/phone/ScrimController.java
@@ -42,6 +42,7 @@ import com.android.internal.util.function.TriConsumer;
 import com.android.keyguard.KeyguardUpdateMonitor;
 import com.android.keyguard.KeyguardUpdateMonitorCallback;
 import com.android.settingslib.Utils;
+import com.android.systemui.animation.Interpolators;
 import com.android.systemui.DejankUtils;
 import com.android.systemui.Dumpable;
 import com.android.systemui.R;
@@ -810,15 +811,7 @@ public class ScrimController implements ViewTreeObserver.OnPreDrawListener, Dump
     }
 
     private float getInterpolatedFraction() {
-        float frac = mPanelExpansion;
-        // let's start this 20% of the way down the screen
-        frac = frac * 1.2f - 0.2f;
-        if (frac <= 0) {
-            return 0;
-        } else {
-            // woo, special effects
-            return (float) (1f - 0.5f * (1f - Math.cos(3.14159f * Math.pow(1f - frac, 2f))));
-        }
+        return Interpolators.getNotificationScrimAlpha(mPanelExpansion);
     }
 
     private void setScrimAlpha(ScrimView scrim, float alpha) {