He studied light and reflection as well as optics. Al-Haytham wrote around 200 books, 47 in mathematics, and 58 in engineering.
Alisoma juu ya mwanga na kuakisiwa kwake pamoja na mambo ya mwanga kwa ujumla. Al-Haytham aliandika takriban vitabu 200, 47 vya hesabu na 58 vya uhandisi.