There is provided an optical low pass filter, which is provided with a first birefringence plate that divides an incident ray into two rays, a second birefringence plate that divides an incident ray into two rays, and a third birefringence plate that divides an incident ray into two rays. The first birefringence plate, the second birefringence plate and the third birefringence plate are cemented to each other, light passed through the first birefringence plate passing through the second birefringence plate and then passing through the third birefringence plate. Further, a separation angle s, representing a difference between separation directions in which adjacent ones of the first, second and third birefringence plates divide their respective incident rays, satisfies a condition 46s60.