https://blog.gongquiz.com/2022/04/22/ct%ec%97%90%ec%84%9c-mtfmodulation-transfer-function%ea%b0%80-%eb%82%98%ed%83%80%eb%82%b4%eb%8a%94-%ec%84%b1%eb%8a%a5%ec%a7%80%ed%91%9c-%ec%9d%98%ea%b3%b5%ea%b8%b0%ec%82%ac-2009%eb%85%84-8/