A lens structure includes a lens tube; a first lens located on a first end-face of the lens tube, where the first lens includes a light converging region and an edge region located at an edge around the light converging region; a light shielding structure covering the edge region of the first lens; and at least one second lens located inside the lens tube. Based on the lens structure, the first lens is disposed on an outer side of a housing of the lens tube. Therefore, an adjustment degree is relatively high, and convenience and flexibility are relatively desirable. In addition, an optical axis of the first lens and an optical axis of the at least one second lens are aligned at a relatively high extent, thereby improving quality of the lens structure and a yield of the lens structure.

Optical lenses and methods for manufacturing optical lenses are disclosed herein. Lenses having a reduced aperture size are also disclosed herein along with methods for making the same. The optical lenses disclosed herein can be made having improved optical properties. The lenses can be used in optical microscopes, including optical microscopes with a shorter optical path relative to conventional optical microscopes.

According to an embodiment, a projection optical system for an image projection device, that includes a plurality of lenses. The projection optical system satisfies conditional expression (1): where fw is a focal length of a lens having the weakest refractive power in the lenses and f is a focal length of the whole projection optical system. $\begin{array}{cc}0.01\le .Math.\frac{f}{f_w}.Math.<0.34& \left(1\right)\end{array}$

An image forming lens system includes an aperture stop, and an image-side lens unit group which is disposed on an image side of the aperture stop. The image-side lens unit group includes a first image-side lens unit having a negative refractive power, a second image-side lens unit having a positive refractive power, and a third image-side lens unit having a negative refractive power. Any one of the first image-side lens unit, the second image side lens unit, and the third image-side lens unit is a focusing lens unit which moves along the optical axis at the time of focusing, and the following conditional expression (1) is satisfied:
0.06<|f.sub.fo/f|<0.4   (1) where, f denotes a focal length of the image forming lens system at the time of focusing at an object at infinity, and f.sub.fo denotes a focal length of the focusing lens unit.

An imaging lens set includes three plastic lens elements, which are a first lens element, a second lens element and a third lens element, and a light blocking sheet. The first lens element includes a first flat abutting portion and a first conical surface. The second lens element includes a second flat abutting portion, a second conical surface, a fourth flat abutting portion and a fourth conical surface. The third lens element includes a third flat abutting portion and a third conical surface. The first flat abutting portion is abutted with the second flat abutting portion, the first conical surface contacts with the second conical surface, and the third conical surface contacts with the fourth conical surface. The light blocking sheet is abutted with the third flat abutting portion and the fourth flat abutting portion, respectively.

A dual-aperture zoom camera comprising a Wide camera with a respective Wide lens and a Tele camera with a respective Tele lens, the Wide and Tele cameras mounted directly on a single printed circuit board, wherein the Wide and Tele lenses have respective effective focal lengths EFL.sub.W and EFL.sub.T and respective total track lengths TTL.sub.W and TTL.sub.T and wherein TTL.sub.W/EFL.sub.W>1.1 and TTL.sub.T/EFL.sub.T<1.0. Optionally, the dual-aperture zoom camera may further comprise an optical OIS controller configured to provide a compensation lens movement according to a user-defined zoom factor (ZF) and a camera tilt (CT) through LMV=CT*EFL.sub.ZF, where EFL.sub.ZF is a zoom-factor dependent effective focal length.

An observation optical system for use in observing an image displayed on an image displaying surface, includes, in order from an observation surface side to the image displaying surface side: a first lens having a first transmission reflective surface and a first transmissive surface; and a second lens having a second transmission reflective surface and a second transmissive surface, in which the first lens and the second lens are arranged via an interval interposed therebetween; light from the image displaying surface transmits through the second lens, is reflected by the first transmission reflective surface, is reflected by the second transmission reflective surface, is transmitted through the first lens, and then travels toward the observation surface side; and a focal length of the first lens and a focal length of the observation optical system are appropriately set.

An image-capturing device includes: a plurality of micro-lenses disposed in a two-dimensional pattern near a focal plane of an image forming optical system; an image sensor that includes a two-dimensional array of element groups each corresponding to one of the micro-lenses and made up with a plurality of photoelectric conversion elements which receive, via the micro-lenses light fluxes from a subject having passed through the photographic optical system and output image signals; and a synthesizing unit that combines the image signals output from the plurality of photoelectric conversion elements based upon information so as to generate synthetic image data in correspondence to a plurality of image forming areas present on a given image forming plane of the image forming optical system, the information specifying positions of the photoelectric conversion elements output image signals that are to be used for generating synthetic image data for each image forming area.

An image-capturing device includes: a plurality of micro-lenses disposed in a two-dimensional pattern near a focal plane of an image forming optical system; an image sensor that includes a two-dimensional array of element groups each corresponding to one of the micro-lenses and made up with a plurality of photoelectric conversion elements which receive, via the micro-lenses light fluxes from a subject having passed through the photographic optical system and output image signals; and a synthesizing unit that combines the image signals output from the plurality of photoelectric conversion elements based upon information so as to generate synthetic image data in correspondence to a plurality of image forming areas present on a given image forming plane of the image forming optical system, the information specifying positions of the photoelectric conversion elements output image signals that are to be used for generating synthetic image data for each image forming area.

A wide-angle lens assembly includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, and a ninth lens. The first lens has negative refractive power and includes a concave surface facing an image side. The second lens has negative refractive power and includes a concave surface facing the image side. The third lens has negative refractive power and includes a concave surface facing the image side. The fourth, fifth, seventh and eighth lenses have refractive power. The sixth and ninth lenses are biconvex lenses with positive refractive power. The first to ninth lenses are arranged in order from an object side to the image side along an optical axis.