cache removal from browser in dot net

hy,

 

i have a website which hold the employee data of organisation.each emaployee image is saved with his  unique id alloted at time of joining.but when if any one change his image after login his id .and update his image old image still shows after refreshing browser 4-5 time new image appears .is there any way new image appears after updating old picture same time

 

i am saving picture in folder