| 摘要 |
PURPOSE:To remove color beats which appear in a scanning direction almost completely and to remove color beats which appear at right angles to the scanning direction sufficiently by superposing a scanning-directional separating birefringent transparent plate and a 45 deg.-directional separating birefringent transparent plate one over the other. CONSTITUTION:An optical filter 20 is formed by superposing the scanning-directional separating birefringent plate 21 and 45 deg.-directional separating birefringent plate 22 one over the other; the thickness of the former is so determined that its separation distance is a half as large as one cycle pitch of the color filter and the thickness of the latter is so determined that its separation distance is a half - quarter as large as one cycle pitch of the color filter. Consequently, the scanning-directional separating birefringent plate removes principal color beats appearing in the scanning direction and the 45 deg.-directional separating birefringent plate reduces other color beats appearing in the scanning direction and color beats appearing at right angles to the scanning direction. Consequently, when this is applied to, specially, a solid-state image pickup element, the color beats appearing in the scanning direction are removed almost completely and the color beats appearing at right angles to the scanning direction are removed sufficiently.
|
