diff --git a/Assets/Scripts/UI/Pages/ConnectDevice/ScanQRcode.cs b/Assets/Scripts/UI/Pages/ConnectDevice/ScanQRcode.cs
index d54be80..3560576 100644
--- a/Assets/Scripts/UI/Pages/ConnectDevice/ScanQRcode.cs
+++ b/Assets/Scripts/UI/Pages/ConnectDevice/ScanQRcode.cs
@@ -277,15 +277,16 @@ namespace Kill.UI.Pages
             // 预览框横向 1080x680
             // 从旋转后的 1080x1920 中截取中间区域并放大
             
-            // 计算中心裁切区域大小（基于 centerCropRatio）
-            int sourceCropH = Mathf.Max(1, Mathf.RoundToInt(camW * centerCropRatio));
-            int sourceCropW = Mathf.Max(1, Mathf.RoundToInt(camH * centerCropRatio));
+            // 计算中心裁切区域大小
+            // centerCropRatio=1.0 时等于原始裁切（取 targetH 列 / 所有行），无缩放
+            // centerCropRatio<1.0 时取更小区域放大，值越小放大倍数越大
+            int sourceCropH = Mathf.Max(1, Mathf.RoundToInt(targetH * centerCropRatio));
+            int sourceCropW = Mathf.Max(1, Mathf.RoundToInt(targetW * centerCropRatio));
             int cropY = (camW - sourceCropH) / 2;
             int cropX = (camH - sourceCropW) / 2;
             
-            // 计算缩放比例
-            float scaleY = (float)sourceCropH / targetH;
-            float scaleX = (float)sourceCropW / targetW;
+            // 两个方向缩放一致，保证不变形
+            float scale = centerCropRatio;
             
             // 获取相机像素数据
             Color32[] cameraPixels = webCamTexture.GetPixels32();
@@ -293,14 +294,14 @@ namespace Kill.UI.Pages
             
             // 顺时针旋转90度 + 中心裁切 + 缩放
             // 目标像素 (x, y) 对应源坐标：
-            //   srcX = cropY + (targetH-1-y) * scaleY  (裁切区域内纵向缩放)
-            //   srcY = cropX + x * scaleX                (裁切区域内横向缩放)
+            //   srcX = cropY + (targetH-1-y) * scale  (裁切区域内纵向缩放)
+            //   srcY = cropX + x * scale                (裁切区域内横向缩放)
             for (int y = 0; y < targetH; y++)
             {
                 for (int x = 0; x < targetW; x++)
                 {
-                    float srcX = cropY + (targetH - 1 - y) * scaleY;
-                    float srcY = cropX + x * scaleX;
+                    float srcX = cropY + (targetH - 1 - y) * scale;
+                    float srcY = cropX + x * scale;
                     
                     // 双线性插值采样
                     int sx = (int)srcX;