Patent attributes
An optical element is disclosed which has an excellent optical low-pass filter effect. The optical element has optical anisotropy and separates entering light into light rays having polarization directions perpendicular to each other. The optical element satisfies the following conditions: 0.1<|ne−no|, and θmax<θ. no and ne represent refractive indices for ordinary and extraordinary rays at a wavelength of 530 nm, θ represents an angle between the direction of an optic axis of the optical element and a normal to an incident surface of the optical element, and θmax represents an angle between the direction of the optic axis and the normal to the incident surface at which the angle of separation is maximized when the light that enters the incident surface of the optical element at the normal angle is separated into the light rays.
