javascript

Question

hi i want to pass the query string values from child page to parent  page now how can i open(refreshed)  parent page from child with query string 

code:
child java script:

function btn1_onclick() {

          window.open('FrmReportStudentYearlyAttendance.aspx?Operation=C&User_ID=' + Student_ID, 'Users', 'left=350,top=250,scrollbars=NO,status=NO,resizable=NO');

      }
here i used window.open() but this opens new window with aspx page
i had tried opener.window()
and window.parent() but these are not working
if possible please send me code