diff --git a/package.json b/package.json
index 9e52ed0..5846f65 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
-  "name": "pinyin",
-  "version": "2.2.0",
+  "name": "pinyinjs",
+  "version": "2.2.1",
   "description": "汉语拼音转换工具。",
   "main": "src/pinyin.js",
   "bin": {
diff --git a/src/pinyin.js b/src/pinyin.js
index f642b08..579df02 100644
--- a/src/pinyin.js
+++ b/src/pinyin.js
@@ -101,7 +101,6 @@ function single_pinyin(han, options){
     return single_pinyin(han.charAt(0), options);
   }
 
-  options = extend(DEFAULT_OPTIONS, options);
   var hanCode = han.charCodeAt(0);
 
   if(!PINYIN_DICT[hanCode]){return [han];}
@@ -155,7 +154,7 @@ function pinyin(hans, options){
 
   if("string" !== typeof hans){return [];}
 
-  options = extend(DEFAULT_OPTIONS, options);
+  options = extend(DEFAULT_OPTIONS, options || {});
 
   var phrases = segment.doSegment(hans);
   var len = hans.length;