The 1-2nd lens group is divided into three lens groups which move when focusing is performed during the magnification change. Even in a case in which the second optical group is formed of one mirror, it is possible for a primary image to contain appropriate aberration and to hereby reduce aberration of an image which is finally projected onto a screen through the second optical group.

An imaging lens for a solid-state imaging sensor includes, in order from an object side to an image side of the imaging lens, a first through sixth lens. The first lens has positive refractive power. The second lens has positive refractive power. The third lens has negative refractive power. The fourth lens has positive or negative refractive power and aspheric surfaces facing the object side and the image side. The fifth lens has positive refractive power. The sixth lens has negative refractive power and aspheric surfaces facing the object side and the image side.

An imaging lens for a solid-state imaging sensor includes, in order from an object side to an image side of the imaging lens, a first through sixth lens. The first lens has positive refractive power. The second lens has positive refractive power. The third lens has negative refractive power. The fourth lens has positive or negative refractive power and aspheric surfaces facing the object side and the image side. The fifth lens has positive refractive power. The sixth lens has negative refractive power and aspheric surfaces facing the object side and the image side.

Wafer-level optical elements and the concave spacer-wafer apertures in which they are formed are disclosed. The wafer-level optical elements include a spacer wafer comprising a plurality of apertures. Each aperture has a concave shape in a planar cross-section of the spacer wafer and an overflow region intersecting the planar cross-section. The wafer-level optical elements also include an array of optical elements, each optical element of the array being formed of cured flowable material within a respective one of the plurality of apertures. A portion of the cured flowable material forming each optical element extends into the overflow region of the respective aperture of the plurality of apertures. The spacer wafer includes a plurality of apertures, each of the plurality of apertures having a concave shape in a planar cross-section of the spacer wafer. Each of the plurality of apertures includes an overflow region intersecting the planar cross-section.

A photographing optical lens assembly includes, in order from object side to image side, a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element, a sixth lens element and a seventh lens element. The first lens element has positive refractive power. The second, third, fourth and fifth lens elements have refractive power. The sixth lens element with refractive power has an image-side surface being concave in a paraxial region, wherein an object-side surface and the image-side surface of the sixth lens element are both aspheric, and the image-side surface has at least one inflection point. The seventh lens element with refractive power has an image-side surface being concave in a paraxial region, wherein an object-side surface and the image-side surface of the seventh lens element are both aspheric, and the image-side surface has at least one inflection point.

A photographing optical lens assembly includes, in order from object side to image side, a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element, a sixth lens element and a seventh lens element. The first lens element has positive refractive power. The second, third, fourth and fifth lens elements have refractive power. The sixth lens element with refractive power has an image-side surface being concave in a paraxial region, wherein an object-side surface and the image-side surface of the sixth lens element are both aspheric, and the image-side surface has at least one inflection point. The seventh lens element with refractive power has an image-side surface being concave in a paraxial region, wherein an object-side surface and the image-side surface of the seventh lens element are both aspheric, and the image-side surface has at least one inflection point.

An imaging lens is substantially constituted by: a negative first lens group; a positive second lens group; an aperture stop; a positive third lens group; and a negative fourth lens group; provided in this order from an object side. The first lens group is constituted only by two or more negative lenses. The second lens group has a positive lens at the most object side thereof. The third lens group has a negative lens having a concave surface toward the object side at the most object side thereof. The fourth lens group is constituted by a single negative lens. The fourth lens group moves from the object side to an image side when changing focus from an object at infinity to an object at an extremely close distance. Only the fourth lens group moves during focusing operations.

An optical apparatus captures imaging light entering into an imager to acquire an image of an object. The optical apparatus includes a lens module and a support. The lens module is configured by a combination of two or more lenses, captures the imaging light through the lenses, and focuses the captured imaging light on the imager. The support supports the lens module at a position apart from the imager by a predetermined distance, such that the imager and the lenses are aligned on the optical axis, and a focal point of the imaging light is formed on the imager. The support is formed such that an expansion-contraction ratio, at which the support expands or contracts along the optical axis in accord with changes in ambient temperature of the optical apparatus, becomes a first expansion-contraction ratio at which the support expands or contracts so as to cancel a movement of the focal point occurring in the lens module along the optical axis in accord with the changes in ambient temperature of the optical apparatus.

An imaging apparatus moves a lens in the optical axis direction with respect to the initialization position, and images a subject. The imaging apparatus includes a first lens, a second lens, a driving unit, a first position detection sensor, a second position detection sensor, a third position detection sensor, and a control unit. The driving unit moves the first lens and second lens in the optical axis direction. The first position detection sensor detects the position of the first lens. The second position detection sensor detects the position of the second lens. The third position detection sensor detects the position of the first lens and the position of the second lens. On the basis of the output from the third position detection sensor, the control unit executes the initializing processing of determining the initialization positions of the first lens and second lens.

A light adjusting apparatus including a drive section provided with an axial magnet, a coil core member and a coil, a first substrate provided an opening and a first cut-out portion, a second substrate provided with an opening and a second cut-out portion, located at a predetermined distance from the first substrate, an incident light adjusting section to which the axial magnet is joined, and an axial magnet support member provided with a distance keeping portion that keeps a distance between the coil core member and the axial magnet to within a certain range and a dropout prevention portion that prevents dropout of the axial magnet from the first cut-out portion, the axial magnet support member being fixed to the coil core member, in which the incident light adjusting section is rotated by the drive section for adjusting the incident light.