Abū ʿAlī al-Ḥasan ibn al-Ḥasan ibn al-Haytham (Arabic:أبو علي، الحسن بن الحسن بن الهيثم‎; c.965 – c.1040 CE), also known by the Latinization Alhazen or Alhacen, was an Arab scientist, mathematician, astronomer, and philosopher. Ibn al-Haytham made significant contributions to the principles of optics, astronomy, mathematics, meteorology, visual pe****tion and the scientific method. He spent most of his life close to the court of the Fatimid Caliphate in Cairo and earned his living authoring various treatises and tutoring members of the nobilities.