Patent ID: 7633542

Claim:
A digital camera system having an interchangeable lens, and first and second camera bodies, each camera body allowing the interchangeable lens to be detachably attached thereto, the digital camera system comprising: a first image pickup element arranged in the first camera body; a first optical low-pass filter being arranged in front of the first image pickup element in the first camera body, a thickness of the first low-pass filter being determined based on a pixel pitch of the first image pickup element, the first optical low-pass filter including a first crystal plate with an angle of rotation of 45°, a first infrared absorbing glass having the same refractive index as that of crystal, a second crystal plate with an angle of rotation of −45° and a third crystal plate with an angle of rotation of 0°; a second image pickup element arranged in the second camera body, the second image pickup element having a smaller pixel pitch than the first image pickup element; and a second optical low-pass filter being arranged in front of the second image pickup element in the second camera body, a thickness of the second low-pass filter being determined based on the pixel pitch of the second image pickup element, the second optical low-pass filter including a fourth crystal plate with an angle of rotation of 0°, a second infrared absorbing glass having the same refractive index as that of crystal, a crystal depolarization plate configured to provide only a depolarization effect and a fifth crystal plate with an angle of rotation of 90°, wherein a thickness of the crystal depolarization plate is set so that the second optical low-pass filter is approximately equal in effective optical path length to the first optical low-pass filter, and wherein, in the first optical low-pass filter, the first crystal plate, the first infrared absorbing glass, the second crystal plate and the third crystal plate are arranged in the aforesaid order from an object side, while in the second optical low-pass filter, the fourth crystal plate, the second infrared absorbing glass, the crystal depolarization plate and the fifth crystal plate are arranged in the last mentioned order from the object side.