diff --git a/TIASshot/Form1.Designer.cs b/TIASshot/Form1.Designer.cs
index f7141dc..9a7a4ad 100644
--- a/TIASshot/Form1.Designer.cs
+++ b/TIASshot/Form1.Designer.cs
@@ -44,6 +44,7 @@
             this.txtMultiShotsInterval = new System.Windows.Forms.TextBox();
             this.label8 = new System.Windows.Forms.Label();
             this.btnOpenDataFolder = new System.Windows.Forms.Button();
+            this.btnLightSW = new System.Windows.Forms.Button();
             ((System.ComponentModel.ISupportInitialize)(this.picPreview)).BeginInit();
             ((System.ComponentModel.ISupportInitialize)(this.picDisplay)).BeginInit();
             this.SuspendLayout();
@@ -262,11 +263,23 @@
             this.btnOpenDataFolder.UseVisualStyleBackColor = true;
             this.btnOpenDataFolder.Click += new System.EventHandler(this.btnOpenDataFolder_Click);
             // 
+            // btnLightSW
+            // 
+            this.btnLightSW.AllowDrop = true;
+            this.btnLightSW.Location = new System.Drawing.Point(173, 517);
+            this.btnLightSW.Name = "btnLightSW";
+            this.btnLightSW.Size = new System.Drawing.Size(110, 37);
+            this.btnLightSW.TabIndex = 21;
+            this.btnLightSW.Text = "照明 OFF";
+            this.btnLightSW.UseVisualStyleBackColor = true;
+            this.btnLightSW.Click += new System.EventHandler(this.btnLightSW_Click);
+            // 
             // Form1
             // 
             this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 12F);
             this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
             this.ClientSize = new System.Drawing.Size(753, 634);
+            this.Controls.Add(this.btnLightSW);
             this.Controls.Add(this.btnOpenDataFolder);
             this.Controls.Add(this.label8);
             this.Controls.Add(this.txtMultiShotsInterval);
@@ -322,6 +335,7 @@
         private System.Windows.Forms.TextBox txtMultiShotsInterval;
         private System.Windows.Forms.Label label8;
         private System.Windows.Forms.Button btnOpenDataFolder;
+        private System.Windows.Forms.Button btnLightSW;
     }
 }
 
diff --git a/TIASshot/Form1.cs b/TIASshot/Form1.cs
index cf1953c..ed7eae3 100644
--- a/TIASshot/Form1.cs
+++ b/TIASshot/Form1.cs
@@ -19,6 +19,7 @@
         public static string APP_NAME = "TIAS Shot";
         private Lucam _lucam;
         private LightSource _light = new LightSource();
+        private bool _isLightOn = true;
 
         /// <summary>
         /// コンストラクタ
@@ -55,7 +56,9 @@
             EnableShots(false);
             _lucam.StartStopPreview();
 
-            _light.Open();
+            if (_light.Open()) {
+                _light.SetLight();
+            }
         }
 
         /// <summary>
@@ -167,5 +170,17 @@
         private void btnOpenDataFolder_Click(object sender, EventArgs e) {
             System.Diagnostics.Process.Start(txtSaveFolder.Text);
         }
+
+        private void btnLightSW_Click(object sender, EventArgs e) {
+            if (_isLightOn) {
+                _light.TurnOff();
+                btnLightSW.Text = "照明 ON";
+                _isLightOn = false;
+            } else {
+                _light.SetLight();
+                btnLightSW.Text = "照明 OFF";
+                _isLightOn = true;
+            }
+        }
     }
 }
diff --git a/TIASshot/LightSource.cs b/TIASshot/LightSource.cs
index 60bb193..927c626 100644
--- a/TIASshot/LightSource.cs
+++ b/TIASshot/LightSource.cs
@@ -10,11 +10,20 @@
 namespace TIASshot {
     internal class LightSource {
         SerialPort _serial;
+        public bool IsOpen { get { return _serial.IsOpen; } }
 
+        /// <summary>
+        /// コンストラクタ
+        /// </summary>
         public LightSource() {
             _serial = new SerialPort();
         }
 
+        /// <summary>
+        /// ポートを探す
+        /// </summary>
+        /// <param name="deviceName"></param>
+        /// <returns></returns>
         private string FindPort(string deviceName) {
             var portname = "";
             var mcW32SerPort = new ManagementClass("Win32_SerialPort");
@@ -28,13 +37,34 @@
             return portname;
         }
 
+        /// <summary>
+        /// 接続
+        /// </summary>
+        /// <returns></returns>
         public bool Open() {
             var portName = FindPort(Config.GetString("LightSourceDevice"));
-            //if (portName == "") return false;
-            //_serial.PortName = portName;
-            //_serial.BaudRate = baudRate;
-            //_serial.Open();
+            if (portName == "") return false;
+            _serial.PortName = portName;
+            _serial.BaudRate = Config.GetInt("LSBaudRate");
+            _serial.DataBits = 8;
+            _serial.StopBits = StopBits.One;
+            _serial.Parity = Parity.None;
+            _serial.Open();
             return true;
         }
+
+        public void TurnOff() {
+            byte[] buf = new byte[] { 0x02, 0x44, 0x41, 0x58, 0x32, 0x3A, 
+                0x44, 0x41, 0x20, 0x30, 0x03, 0x31, 0x45, 0x04 };
+            var str = Encoding.ASCII.GetString(buf);
+            _serial.Write(str);
+        }
+
+        public void SetLight() {
+            byte[] buf = new byte[] { 0x02, 0x44, 0x41, 0x58, 0x32, 0x3A, 0x44, 
+                0x45, 0x46, 0x20, 0x33, 0x30, 0x37, 0x32, 0x03, 0x30, 0x34, 0x04 };
+            var str = Encoding.ASCII.GetString(buf);
+            _serial.Write(str);
+        }
     }
 }
diff --git a/TIASshot/config.xml b/TIASshot/config.xml
index 92179a8..88c0b5d 100644
--- a/TIASshot/config.xml
+++ b/TIASshot/config.xml
@@ -26,4 +26,5 @@
 	<ConvSrgb2XyzSaveFile>conv_srgb_xyz.csv</ConvSrgb2XyzSaveFile>
 	<SaveFolder>C:\TIAS_Data</SaveFolder>
 	<LightSourceDevice>Silicon Labs CP210x</LightSourceDevice>
+	<LSBaudRate>38400</LSBaudRate>
 </Config>