Ext.panel 显示图片有关问题

{
                    xtype:'panel',
                    layout:'column', 
                    bodyStyle:'background:transparent repeat-y 0 0',                    
                    border:false,
                    anchor:"98%",                  
                    items:[{
                        columnWidth:.6, 
                        border:false ,                      
                        xtype: 'form',                              
                        defaultType:'textfield',
                        bodyStyle:'background:transparent repeat-y 0 0',
                        defaults:{
                            anchor:'90%'                           
                        },
                        items:[{    
                            labelWidth:60,                         
                            fieldLabel:"验证码",                          
                            name:'validate',
                            allowBlank:false,
                            blankText: '验证码不能为空'
                        }]                       
                       
                    },{    
                        columnWidth:.4,                   
                        border:false,
                        xtype:'panel',
                        bodyStyle:'background:transparent repeat-y 0 0',
                        height:23,
                        width:100,
                        anchor:'85%',                        
                        html:"<img src='action.aspx' width='80' height='25' alt=\"点击显示图片\"  />"
                    }