Seiko Precision Inc.

Junichi Nio

Kazuo Akimoto

Motoharu Sakurai

A first lens (L), a second lens (L), a third lens (L), and a fourth lens (L) are arranged in this order from an object side. The first lens (L) has a biconvex shape and a positive refracting power. The second lens (L) has a meniscus shape that is convex toward the object side, and has a negative refracting power. The third lens (L) has a meniscus shape that is convex toward an image side, and has a positive refracting power. The fourth lens (L) has a meniscus shape that is convex toward the object side, and has a negative refracting power. A chromatic aberration generated by the first lens (L) is corrected by the second lens (L). A chromatic aberration generated by the third lens (L) is corrected by the fourth lens (L).

Imaging lens, and imaging device and mobile terminal apparatus using the same

An imaging lens comprises a first lens (L), a second lens (L), a third lens (L), and a fourth lens (L), which are arranged in ascending sequence, starting from the lens nearest to the object. The first lens (L) has a double-convex shape and positive refractive power. The second lens (L) has a double-concave shape and negative refractive power. The third lens (L) has a meniscus shape with its convex surface facing an image plane, and has positive refractive power. The fourth lens (L) has a meniscus shape with its convex surface facing the object. A chromatic aberration occurred in the first lens (L) is corrected by the second lens (L). A chromatic aberration occurred in the third lens (L) is corrected by the fourth lens (L).

Imaging lens, and imaging apparatus and mobile terminal apparatus using the same

An imaging lens enables a large focal depth and low error sensitivity. The imaging lens satisfies '0.016&#x3c;&#x394;/f&#x3c;0.018,' where &#x394; is the absolute value of longitudinal chromatic aberrations at F curve and C curve wavelengths, and f is the combined focal distance of the entire compound imaging lens. A first, a second, and a third lens are disposed sequentially, the first lens disposed toward an object, and the third lens disposed toward an image surface. The first lens has a positive refraction, a meniscus shape, and a convex surface facing the object. The second lens has a meniscus shape with a concave surface facing the object. The third lens has a convex-type shape facing the object; and a concave-type aspherical shape facing the image surface, providing a negative refraction in a radially central portion and a positive refraction in a radially peripheral portion.

Imaging lens

An imaging lens has a compact shape and sufficiently compensates for various aberrations. The imaging lens includes a first lens, a second lens, and a third lens disposed sequentially, with the first lens toward an object. The conditions '0.5H&#x3c;T0&#x3c;0.7H,' '2&#x3c;&#x3c6;r4/&#x3c6;&#x3c;2.5,' and &#x201c;0.15&#x3c;&#x3c6;r5/&#x3c6;&#x3c;0.3&#x201d; are satisfied, where: H is the effective radius of the surface of the third lens facing an image surface; T0 is the distance between the optical axis and a point on a line parallel to the optical axis and normal to the surface of the third lens facing the image surface; &#x3c6; is the combined refractive power of the imaging lens; &#x3c6;r4 is the refractive power of the surface of the second lens facing the image surface; and &#x3c6;r5 is the refractive power of the surface of the third lens facing the object.

To achieve light blocking performance firmly by a simple constitution with no need of separately providing a special member, a photographing element is provided on a front face side of a circuit board for a camera and a light blocking member is provided on a rear face side thereof. Connection terminal portions++ are arranged to align at a peripheral portion of the board. As the light blocking member on the rear face side, a conductive pattern or a resist having light blocking performance is used and the conductive pattern is integrally formed with one of the connection terminal portions and the resist is formed at portions excluding the connection terminal portions. The conductive pattern may be formed by copper paste and the resist may be formed by a resist of black color or the like. A recessed portionfor containing the photographing element is provided on die front face side or the board and the resist having light blocking performance of a resist of black color or the like is provided at an inner face of the recessed portion. An optical apparatus unit having a lens to focus an object on the photographing element is connected to the front face side of the circuit board.

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Chiba, Japan

Junichi Nio