diff --git a/.gitignore b/.gitignore
index 660c7b1..d98d406 100644
--- a/.gitignore
+++ b/.gitignore
@@ -41,4 +41,7 @@ main.spec
 dist/output/
 dist/main.exe
 *.whl
-win_driver/
\ No newline at end of file
+win_driver/
+claude.md
+src/services/__pycache__/device_service.cpython-312.pyc
+src/__pycache__/config.cpython-312.pyc
diff --git a/src/models/video_thread.py b/src/models/video_thread.py
index 3b8ec2f..77ddd5a 100644
--- a/src/models/video_thread.py
+++ b/src/models/video_thread.py
@@ -1,30 +1,67 @@
 import cv2
+import time
+import threading
 from PyQt5.QtCore import QThread, pyqtSignal
 from PyQt5.QtGui import QImage
 
 class VideoThread(QThread):
     change_pixmap_signal = pyqtSignal(QImage)
+    camera_error_signal = pyqtSignal(str)  # 新增：相機錯誤信號
 
     def __init__(self):
         super().__init__()
         self._run_flag = True
         self._camera_open_attempts = 0
         self._max_attempts = 3
+        self._camera_timeout = 5  # 相機開啟超時秒數
+
+    def _open_camera_with_timeout(self, camera_index, backend=None):
+        """使用超時機制開啟相機"""
+        cap = None
+        open_success = False
+
+        def try_open():
+            nonlocal cap, open_success
+            try:
+                if backend is not None:
+                    cap = cv2.VideoCapture(camera_index, backend)
+                else:
+                    cap = cv2.VideoCapture(camera_index)
+                open_success = cap is not None and cap.isOpened()
+            except Exception as e:
+                print(f"開啟相機時發生異常: {e}")
+                open_success = False
+
+        # 在單獨的線程中嘗試開啟相機
+        thread = threading.Thread(target=try_open)
+        thread.daemon = True
+        thread.start()
+        thread.join(timeout=self._camera_timeout)
+
+        if thread.is_alive():
+            print(f"相機開啟超時 ({self._camera_timeout}秒)")
+            return None
+
+        if open_success:
+            return cap
+        else:
+            if cap is not None:
+                cap.release()
+            return None
 
     def run(self):
         # 嘗試多次開啟相機
         while self._camera_open_attempts < self._max_attempts and self._run_flag:
             self._camera_open_attempts += 1
             print(f"嘗試開啟相機 (嘗試 {self._camera_open_attempts}/{self._max_attempts})...")
-            
+
             # 嘗試使用DirectShow後端，通常在Windows上更快
-            cap = cv2.VideoCapture(0, cv2.CAP_DSHOW)
-            if not cap.isOpened():
+            cap = self._open_camera_with_timeout(0, cv2.CAP_DSHOW)
+            if cap is None:
                 print("無法使用DirectShow開啟相機，嘗試預設後端")
-                cap = cv2.VideoCapture(0)
-                if not cap.isOpened():
+                cap = self._open_camera_with_timeout(0)
+                if cap is None:
                     print(f"無法使用任何後端開啟相機，等待1秒後重試...")
-                    import time
                     time.sleep(1)
                     continue
             
diff --git a/src/services/device_service.py b/src/services/device_service.py
index ed0cedc..bccb90e 100644
--- a/src/services/device_service.py
+++ b/src/services/device_service.py
@@ -1,18 +1,63 @@
 import kp
+import threading
+
+class EmptyDescriptor:
+    def __init__(self):
+        self.device_descriptor_number = 0
+        self.device_descriptor_list = []
+
+def check_available_device(timeout=0.5):
+    """
+    掃描可用設備，帶有超時機制
+
+    Args:
+        timeout: 超時秒數，預設 5 秒
+
+    Returns:
+        設備描述符
+    """
+    result = [None]
+    error = [None]
+
+    def scan_devices():
+        try:
+            result[0] = kp.core.scan_devices()
+        except Exception as e:
+            error[0] = e
 
-def check_available_device():
     try:
-        print("checking available devices")
-        device_descriptors = kp.core.scan_devices()
-        print("device_descriptors", device_descriptors)
-        return device_descriptors
+        print("[SCAN] 開始掃描設備...")
+
+        # 在單獨的線程中執行掃描
+        thread = threading.Thread(target=scan_devices)
+        thread.daemon = True
+        print("[SCAN] 啟動掃描線程...")
+        thread.start()
+        print(f"[SCAN] 等待掃描完成 (超時: {timeout}秒)...")
+        thread.join(timeout=timeout)
+
+        if thread.is_alive():
+            print(f"[SCAN] 設備掃描超時 ({timeout}秒)")
+            return EmptyDescriptor()
+
+        print("[SCAN] 掃描線程已完成")
+
+        if error[0]:
+            print(f"[SCAN] Error scanning devices: {error[0]}")
+            return EmptyDescriptor()
+
+        if result[0] is None:
+            print("[SCAN] 結果為 None")
+            return EmptyDescriptor()
+
+        print("[SCAN] device_descriptors:", result[0])
+        print("[SCAN] 準備返回結果...")
+        import sys
+        sys.stdout.flush()
+        return result[0]
+
     except Exception as e:
-        print(f"Error scanning devices: {e}")
-        # 返回一個空的設備描述符或模擬數據
-        class EmptyDescriptor:
-            def __init__(self):
-                self.device_descriptor_number = 0
-                self.device_descriptor_list = []
+        print(f"[SCAN] Error scanning devices: {e}")
         return EmptyDescriptor()
 
 # def check_available_device():
diff --git a/src/views/components/device_list.py b/src/views/components/device_list.py
index 1fb08fd..4812ee6 100644
--- a/src/views/components/device_list.py
+++ b/src/views/components/device_list.py
@@ -11,11 +11,9 @@ def create_device_layout(parent, device_controller):
     try:
         devices_frame = QFrame(parent)
         devices_frame.setStyleSheet(f"border: none; background: {SECONDARY_COLOR}; border-radius: 15px;")
-        
-        # Set height based on connected devices
-        base_height = 250
-        extra_height = 100 if len(device_controller.connected_devices) > 1 else 0
-        devices_frame.setFixedHeight(base_height + extra_height)
+
+        # 固定高度，避免滾輪問題
+        devices_frame.setFixedHeight(200)
         devices_frame.setFixedWidth(240)
         
         devices_layout = QVBoxLayout(devices_frame)
@@ -53,7 +51,15 @@ def create_device_layout(parent, device_controller):
             QListWidget::item:selected {
                 background-color: rgba(255, 255, 255, 0.2);
             }
+            QScrollBar:vertical {
+                width: 0px;
+            }
+            QScrollBar:horizontal {
+                height: 0px;
+            }
         """)
+        device_list_widget.setVerticalScrollBarPolicy(Qt.ScrollBarAlwaysOff)
+        device_list_widget.setHorizontalScrollBarPolicy(Qt.ScrollBarAlwaysOff)
         
         # Connect item selection signal
         device_list_widget.itemClicked.connect(lambda item: device_controller.select_device(
diff --git a/src/views/components/device_popup.py b/src/views/components/device_popup.py
index b9ba9bb..ef6cd98 100644
--- a/src/views/components/device_popup.py
+++ b/src/views/components/device_popup.py
@@ -207,8 +207,10 @@ def create_device_popup(parent, device_controller):
 def refresh_devices(parent, device_controller):
     """Refresh the device list and update the UI"""
     try:
+        print("[POPUP] 開始刷新設備列表...")
         # Call the refresh method from device controller
         device_controller.refresh_devices()
+        print("[POPUP] device_controller.refresh_devices() 完成")
         
         # Clear the list
         parent.device_list_widget_popup.clear()
diff --git a/src/views/mainWindows.py b/src/views/mainWindows.py
index dc586b0..35f1494 100644
--- a/src/views/mainWindows.py
+++ b/src/views/mainWindows.py
@@ -14,6 +14,7 @@ from src.views.components.device_list import create_device_layout
 from src.views.components.toolbox import create_ai_toolbox
 from src.views.components.media_panel import create_media_panel
 from src.views.components.device_popup import create_device_popup, refresh_devices
+from src.views.components.custom_model_block import create_custom_model_block
 
 class MainWindow(QWidget):
     def __init__(self):
@@ -92,10 +93,11 @@ class MainWindow(QWidget):
             # 3. Refresh devices - do this after UI is fully set up
             QTimer.singleShot(100, self.device_controller.refresh_devices)
             
-            self.auto_start_camera()
-
             # # 4. Show popup
             self.show_device_popup()
+
+            # 5. 延遲啟動相機，讓 UI 先完全顯示
+            QTimer.singleShot(500, self.auto_start_camera)
             print("Popup window setup complete")
             
             # # 5. Start camera automatically after a short delay
@@ -109,9 +111,13 @@ class MainWindow(QWidget):
             main_layout = QHBoxLayout(main_page)
             main_page.setLayout(main_layout)
 
-            # Left layout
-            left_layout = QVBoxLayout()
-            main_layout.addLayout(left_layout, 1)
+            # Left layout - 使用固定寬度的容器，避免滾輪
+            left_container = QWidget()
+            left_container.setFixedWidth(260)
+            left_layout = QVBoxLayout(left_container)
+            left_layout.setContentsMargins(10, 10, 10, 10)
+            left_layout.setSpacing(10)
+            main_layout.addWidget(left_container)
 
             # Add Kneron logo
             logo_label = QLabel()
@@ -121,12 +127,16 @@ class MainWindow(QWidget):
             logo_label.setPixmap(scaled_logo)
             left_layout.addWidget(logo_label)
             
-            # Add device list and AI toolbox
+            # Add device list and custom model block
             self.device_frame, self.device_list_widget = create_device_layout(self, self.device_controller)
             left_layout.addWidget(self.device_frame)
-            
-            self.toolbox_frame = create_ai_toolbox(self, self.config_utils, self.inference_controller)
-            left_layout.addWidget(self.toolbox_frame)
+
+            # 使用 Custom Model Block 取代原本的 AI Toolbox
+            self.custom_model_frame = create_custom_model_block(self, self.inference_controller)
+            left_layout.addWidget(self.custom_model_frame)
+
+            # 添加彈性空間，確保元件不會被拉伸
+            left_layout.addStretch()
 
             # Right layout
             right_container = QWidget()
@@ -175,13 +185,12 @@ class MainWindow(QWidget):
             
     def show_device_popup(self):
         try:
-            # 顯示彈窗前刷新設備列表
-            # 使用新的 refresh_devices 函數，而不是直接調用 device_controller
-            from src.views.components.device_popup import refresh_devices
-            refresh_devices(self, self.device_controller)
-            
-            # 顯示彈窗
+            # 先顯示彈窗
             self.overlay.show()
+
+            # 延遲刷新設備列表，讓 UI 先顯示
+            from src.views.components.device_popup import refresh_devices
+            QTimer.singleShot(100, lambda: refresh_devices(self, self.device_controller))
         except Exception as e:
             print(f"Error in show_device_popup: {e}")
             
diff --git a/src/views/utilities_screen.py b/src/views/utilities_screen.py
index f03a502..2a79ace 100644
--- a/src/views/utilities_screen.py
+++ b/src/views/utilities_screen.py
@@ -68,8 +68,8 @@ class UtilitiesScreen(QWidget):
         # 添加內容容器到主佈局
         self.main_layout.addWidget(self.content_container, 1)
         
-        # Initialize with device refresh
-        QTimer.singleShot(500, self.refresh_devices)
+        # Initialize with device refresh (暫時禁用自動刷新，避免阻塞)
+        # QTimer.singleShot(500, self.refresh_devices)
 
     def create_header(self):
         """Create the header with back button and logo"""