diff --git a/src/main/java/org/aohe/core/sane/utils/SaneSessionUtils.java b/src/main/java/org/aohe/core/sane/utils/SaneSessionUtils.java
index 652d3f0..ba80436 100644
--- a/src/main/java/org/aohe/core/sane/utils/SaneSessionUtils.java
+++ b/src/main/java/org/aohe/core/sane/utils/SaneSessionUtils.java
@@ -142,13 +142,13 @@ public class SaneSessionUtils {
         try {
             saneDevice.open();
             BufferedImage bufferedImage =  saneDevice.acquireImage();
-            File file = FileUtil.createTempFile("sane","png",true);
+            File file = FileUtil.createTempFile("sane-",".png",true);
             ImageIO.write(bufferedImage, "png", file);
             return file;
         } catch (IOException | SaneException e) {
             throw new RuntimeException(e);
         }finally {
-            if(saneDevice != null){
+            if(saneDevice != null && saneDevice.isOpen()){
                 saneDevice.close();
             }
         }