diff --git a/HPPA/AppSettings.cpp b/HPPA/AppSettings.cpp
index dc6f028..e7c07a8 100644
--- a/HPPA/AppSettings.cpp
+++ b/HPPA/AppSettings.cpp
@@ -11,7 +11,7 @@ const QString AppSettings::kDefaultDepthCameraDataFolder = QString();
 const double AppSettings::kDefaultScanSpeed = 1.0;
 const double AppSettings::kDefaultReturnSpeed = 5.0;
 const int AppSettings::kDefaultGonggaShanRecordPort = 666;
-const QString AppSettings::kDefaultHyperimgDisplayMode = QStringLiteral("full");
+const AppSettings::HyperimgDisplayMode AppSettings::kDefaultHyperimgDisplayMode = HyperimgDisplayMode::Waterfall;
 
 AppSettings::AppSettings()
 	: m_settings(QSettings::IniFormat, QSettings::UserScope,
@@ -150,12 +150,14 @@ void AppSettings::setGonggaShanRecordPort(int value)
 	m_settings.setValue("GonggaShanRecordCtl/Port", value);
 }
 
-QString AppSettings::hyperimgDisplayMode() const
+AppSettings::HyperimgDisplayMode AppSettings::hyperimgDisplayMode() const
 {
-	return m_settings.value("Display/HyperimgDisplayMode", kDefaultHyperimgDisplayMode).toString();
+	return static_cast<HyperimgDisplayMode>(
+		m_settings.value("Display/HyperimgDisplayMode",
+			static_cast<int>(kDefaultHyperimgDisplayMode)).toInt());
 }
 
-void AppSettings::setHyperimgDisplayMode(const QString& mode)
+void AppSettings::setHyperimgDisplayMode(HyperimgDisplayMode mode)
 {
-	m_settings.setValue("Display/HyperimgDisplayMode", mode);
+	m_settings.setValue("Display/HyperimgDisplayMode", static_cast<int>(mode));
 }
diff --git a/HPPA/AppSettings.h b/HPPA/AppSettings.h
index 889f226..5fbf564 100644
--- a/HPPA/AppSettings.h
+++ b/HPPA/AppSettings.h
@@ -50,9 +50,12 @@ public:
 	int gonggaShanRecordPort() const;
 	void setGonggaShanRecordPort(int value);
 
-	// 图像显示模式（full / waterfall）
-	QString hyperimgDisplayMode() const;
-	void setHyperimgDisplayMode(const QString& mode);
+	// 图像显示模式枚举
+	enum class HyperimgDisplayMode { Full, Waterfall };
+
+	// 图像显示模式
+	HyperimgDisplayMode hyperimgDisplayMode() const;
+	void setHyperimgDisplayMode(HyperimgDisplayMode mode);
 	// 在此处添加更多参数的 getter/setter ...
 
 private:
@@ -73,5 +76,5 @@ private:
 	static const double kDefaultScanSpeed;
 	static const double kDefaultReturnSpeed;
 	static const int kDefaultGonggaShanRecordPort;
-	static const QString kDefaultHyperimgDisplayMode;
+	static const HyperimgDisplayMode kDefaultHyperimgDisplayMode;
 };
diff --git a/HPPA/ImageViewer.cpp b/HPPA/ImageViewer.cpp
index 663b6fb..0fd88db 100644
--- a/HPPA/ImageViewer.cpp
+++ b/HPPA/ImageViewer.cpp
@@ -79,11 +79,11 @@ void Mapcavas::SetImage(QPixmap *image)
         m_GraphicsPixmapItemHandle->setPixmap(*image);
     }
 
-    if (m_displayMode =="full")
+    if (m_displayMode == AppSettings::HyperimgDisplayMode::Full)
     {
         ensureSceneVisible();
     }
-    else if (m_displayMode == "waterfall")
+    else if (m_displayMode == AppSettings::HyperimgDisplayMode::Waterfall)
     {
         ensureWaterfallVisible();
     }
diff --git a/HPPA/ImageViewer.h b/HPPA/ImageViewer.h
index f9302c2..6d96f97 100644
--- a/HPPA/ImageViewer.h
+++ b/HPPA/ImageViewer.h
@@ -80,7 +80,7 @@ private:
 	QGraphicsLineItem* m_hLine = nullptr;  // horizontal line
 	QGraphicsLineItem* m_vLine = nullptr;  // vertical line
 
-	QString m_displayMode;
+	AppSettings::HyperimgDisplayMode m_displayMode;
 
 signals:
 	void leftMouseButtonPressed(int, int, QVector<double>, QVector<double>);
diff --git a/HPPA/setWindow.cpp b/HPPA/setWindow.cpp
index 03298ca..548d93b 100644
--- a/HPPA/setWindow.cpp
+++ b/HPPA/setWindow.cpp
@@ -10,6 +10,7 @@ setWindow::setWindow(QWidget* parent)
 
 	setWindowFlags(Qt::FramelessWindowHint);
 
+	//顺序不能更改，和AppSettings::HyperimgDisplayMode一致
 	ui.hyperimgDisplayMode_comboBox->addItem("full");
 	ui.hyperimgDisplayMode_comboBox->addItem("waterfall");
 
@@ -28,13 +29,17 @@ void setWindow::loadSettings()
 {
 	ui.dataFolderLineEdit->setText(AppSettings::instance().dataFolder());
 
-	ui.hyperimgDisplayMode_comboBox->setCurrentText(AppSettings::instance().hyperimgDisplayMode());
+	ui.hyperimgDisplayMode_comboBox->setCurrentIndex(
+		static_cast<int>(AppSettings::instance().hyperimgDisplayMode()));
 }
 
 void setWindow::saveSettings()
 {
 	AppSettings::instance().setDataFolder(ui.dataFolderLineEdit->text());
-	AppSettings::instance().setHyperimgDisplayMode(ui.hyperimgDisplayMode_comboBox->currentText());
+	AppSettings::instance().setHyperimgDisplayMode(
+		ui.hyperimgDisplayMode_comboBox->currentIndex() == 0
+		? AppSettings::HyperimgDisplayMode::Full
+		: AppSettings::HyperimgDisplayMode::Waterfall);
 }
 
 void setWindow::onSelectDataFolder()