| 摘要 |
A digital camera includes: a lens unit that forms a subject image on an imaging plane; an image sensor that includes color filters each disposed at one of pixels disposed in a lattice-like pattern over pixel intervals (a, b) along two directions, an x direction and a y direction, extending perpendicular to each other, with color filters corresponding to a first color component among first through nth (n≧2) color components, disposed in a checkered pattern at pixels amounting to at least half an entire color filter density and color filters corresponding to remaining color components disposed at other pixels, and outputs image signals expressing the subject image; and an optical low pass filter unit at which light having passed through the lens unit and yet to enter the image sensor undergoes light beam separation along two diagonal directions ((1/2)a, (1/2)b)×(√2/α) and ((1/2)a, −(1/2)b)×(√2/α) relative to (x, y) coordinate axes, so as to achieve frequency modulation for the subject image to become extinct at a band formed by connecting spatial frequencies (α/(2a), 0) and (0, α/(2b)) at positions calculated by multiplying, by a multiplier α, a Nyquist frequency 1/(2a) and a Nyquist frequency 1/(2b) at the image sensor assumed respectively along the x direction and the y direction. When the pixel intervals (a, b) assumed along the two directions at the image sensor are both within a 2.5˜5 μm/pixel range, a position of an extinction frequency band is set for the optical low pass filter by setting the multiplier α for the Nyquist frequencies at the image sensor within a range of 1.5≦̸α≦̸3.5.
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