Abstract: A compound eye image-taking system which can obtain bright parallax images and calculate proper parallax information from these parallax images by a simple and compact construction, is disclosed. This compound eye image-taking system comprises of an optical element array in which a plurality of optical elements. The optical axes of the optical elements are different to each other. Additionally, the system comprises of a image-pickup unit in which a plurality of image-pickup portions which are formed on the same semiconductor substrate and picks up images formed by the optical elements, respectively; and a parallax calculating circuit which calculates parallax information between images picked-up by the image-pickup portions.

Abstract: The invention makes easy acquisition of depth distance information of a subject possible by a small-sized device. In a compound eye imaging system comprising a compound eye optical system having a plurality of optical blocks and an imaging element for picking-up object images formed by the optical blocks in imaging ranges provided for each optical block, the optical axes of the optical blocks are made to intersect each other at the object side.

Abstract: An optical element includes an incidence surface, one or more reflecting surfaces reflecting light from the incident surface, an emergence surface, and off-axial curved surfaces causing the light to emerge from the emergence surface. At least one of the incidence surface, the emergence surface and the one or more reflecting surfaces is a surface having diffracting action. The surface having the diffracting action is a curved surface.

Abstract: An optical element has a first optical member which is a transparent body having two refracting surfaces and a reflecting, curved surface symmetric only with respect to one symmetry plane and a reference axis of which is present in the symmetry plane; and a second optical member which is a transparent body having two refracting surfaces and a reflecting surface and a reference axis of which is not present in the symmetry plane. One refracting surface of the second optical member is coupled to one refracting surface of the first optical member. The reference axis is defined by a ray passing an image center and a pupil center of an optical system including the optical element.

Abstract: An optical system includes an optical element having a plurality of reflective surfaces integrally formed, at least one reflective surface out of the plurality of reflective surfaces of the optical element being a curved surface a normal to which at an intersecting point with a reference axis does not coincide with the reference axis, an image pickup element to which light successively reflected by the plurality of reflective surfaces is incident, and an optical member for making at least part of the light that ought to enter the image pickup element, travel in an optical path different from an optical path toward the image pickup element. The light made to travel in the different optical path by the optical member is utilized for a purpose other than image pickup by said image pickup element.

Abstract: An image pickup optical system has an optical element of a transparent, optical material including an entrance surface, at least one reflective surface, and an exit surface. The optical element has an optical power, the image pickup optical system has an image pickup element including a plurality of pixels. On the image pickup element an image is formed by light from an object through the optical element. The optical material is a material having an index change amount &Dgr;n from an absolute dry condition at the temperature of 50° C. to saturation under a circumstance of the temperature being 50° C.

Abstract: In an optical element for reflecting light from an incidence surface of the optical element by one or more reflecting surfaces comprising off-axial curved surfaces, and causing the light to emerge from an emergence surface, at least one of the incidence surface, the emergence surface and the reflecting surface diffracting the light.