电子科发女学光电科学与工程学院 SCHOOL OF OPTOELECTRONIC SCIENCE AND ENGINEERING OF UESTC A Brief History Jean Baptiste Joseph Fourier: French mathematician,born in 1768 in the town of Auxerre. ■ Fourier's contribution states that any periodic function can be expressed as the sum of sines and/or cosines of different frequencies,each multiplied by a different coefficient (we now Fourier(1768-1830) call this sum a Fourier series).A Brief History ◼ Jean Baptiste Joseph Fourier: French mathematician, born in 1768 in the town of Auxerre. ◼ Fourier’s contribution states that any periodic function can be expressed as the sum of sines and/or cosines of different frequencies, each multiplied by a different coefficient (we now call this sum a Fourier series). Fourier(1768 –1830)