Abstract: A miniature zoom lens includes a first, a second and a third lens groups arranged along an optical axis and from an object side to an image side in sequence. The refractive powers of the three lens groups are negative, positive and positive, respectively. The first lens group is fixed at a predetermined position. The second lens group is movable along the optical axis in accordance with a change of magnification. The third lens group is movable along the optical axis for keeping an image plane fixed at an image sensor. The first lens group is in resting state and the second and the third lens groups are movable during zoom-in or zoom-out operation of the miniature zoom lens. In addition, the miniature zoom lens can be composed of at least seven pieces of lens, thus the cost is reduced, the manufacture is easy and the assembly is simple.

Abstract: An imaging lens includes a first group having a positive or negative refractive power, a second group having a positive refractive power, a third group having a positive or negative refractive power, which are sequentially arranged from the object side of the imaging lens. The first group includes an aperture stop, and the second group includes a positive lens, and a cemented lens of a positive lens and a negative lens. The third group is composed of a cemented lens of a positive lens and a negative lens, and the following formula (1) is satisfied: 0.5?f2/f?1.2??(1), where f: focal length of the entire system of the imaging lens, and f2: focal length of the second group.

Abstract: An optical system having a larger total lens length than a focal length includes lenses L and NL on at least one of a magnification conjugate side and a reduction conjugate side with respect to an aperture stop. The lens L satisfies conditional expressions as follows, ?1.68×10?3·?L+0.590<?L<3.15×10?4·?L2?1.86×10?2·?L+0.878, and 5<?L<27, where ?L and ?L are an Abbe number and a gF-line partial dispersion ratio of the lens L. The refractive power of the lens L is positive when located at the magnification conjugate side, or negative when located at the reduction conjugate side.

Abstract: A variable magnification optical system includes first-lens-group having negative refractive power, aperture stop, and second-lens-group having positive refractive power, arranged from the object-side. An aspheric lens, a central portion of the object-side surface of which is convex, is arranged on the most object-side of the second-lens-group. The object-side surface of the aspheric lens is formed in such a manner that positive power decreases from the central portion of the object-side surface of the aspheric lens toward the periphery thereof, or that an inflection point is present between the central portion and the periphery and positive power decreases as a distance from the central portion increases between the central portion and the inflection point, and negative power increases toward the periphery between the inflection point and the periphery. The aspheric surface satisfies the following formulas (1) and (2) about refractive index and Abbe number: Ne5<1.53??(1); and ?d5>75??(2).

Abstract: The present invention relates to an electromagnetic beam converter and a method for conversion of an input beam of electromagnetic radiation having a bell shaped intensity profile a(x,y) into an output beam having a prescribed target intensity profile I(x?,y?) based on a further development of the generalized phase contrast method.

Abstract: An image pickup optical system made of five lenses, includes in order from an object side, an aperture stop, a first lens L1 having a positive refracting power, a second lens L2 having a negative refracting power, a third lens L3 having a positive refracting power, a fourth lens L4 having a positive refracting power, and a fifth lens L5 having a negative refracting power. Moreover, an image pickup apparatus includes this image pickup optical system.

Abstract: A zoom optical system including a first lens group including a plastic aspherical lens and having a negative refractive power, a second lens group having a positive refractive power, and a third lens group having a positive refractive power, wherein the first lens group, the second lens group and the third lens group are arrange sequentially from an object side to an image side, and wherein the plastic aspherical lens satisfies the following Inequality: 0?(R21?R22)2?0.04, where R21 denotes the radius of curvature of the plastic aspherical lens corresponding to the object side, and R22 denotes the radius of curvature of the plastic aspherical lens corresponding to the image side.

Abstract: The present invention provides an optical imaging lens assembly comprising, in order from an object side to an image side: a first lens element with positive refractive power having a convex object-side surface; a second lens element with negative refractive power having a concave object-side surface; and a third lens element with negative refractive power having a concave image-side surface, at least one of the object-side and image-side surfaces thereof being aspheric. With the aforementioned arrangement of lens elements, the total track length of the optical imaging lens assembly can be effectively reduced, the sensitivity of the optical system can be attenuated, a large field of view can be achieved and the image quality can be improved.

Abstract: A tunable acoustic gradient index of refraction (TAG) lens and system are provided that permit, in one aspect, dynamic selection of the lens output, including dynamic focusing and imaging. The system may include a TAG lens and at least one of a source and a detector of electromagnetic radiation. A controller may be provided in electrical communication with the lens and at least one of the source and detector and may be configured to provide a driving signal to control the index of refraction and to provide a synchronizing signal to time at least one of the source and the detector relative to the driving signal. Thus, the controller is able to specify that the source irradiates the lens (or detector detects the lens output) when a desired refractive index distribution is present within the lens, e.g. when a desired lens output is present.

Abstract: A solar concentrator comprises a curved linear Fresnel lens (16) which has a plurality of prismatic features (10, 12, 14). The prismatic features are arranged into at least two segments, in each segment the prismatic features have a common apex angle, the common apex angle differing between adjacent segments. A method of manufacturing a mold (2) for producing a Fresnel lens optical film (16) is disclosed. The method comprises rotating a mold blank, and forming a plurality of different prismatic features (10, 12, 14) on the mold blank by repeatedly advancing a cutting tool (4) onto and then withdrawing the tool away from the surface of the mold blank.

Abstract: Disclosed are a zoom lens and an imaging apparatus having a high zoom ratio, a small total length, and a small overall size. A zoom lens includes a first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power, a fourth lens group having a negative refractive power, and a fifth lens group having a positive refractive power which are arranged in this order from an object side. A gap between the lens groups is changed to change power. The zoom lens satisfies the following Condition expression 1: 0.05<|f4|/ft<0.25??[Condition expression 1] (where ft indicates the focal length of the entire system at a telephoto end and f4 indicates the focal length of the fourth lens group).

Abstract: A zoom lens includes, in order from an object-side to an image-plane-side: a positive first lens unit; a negative second lens unit; a stop; a positive third lens unit; a negative fourth lens unit; and a positive fifth lens unit, wherein: during zooming, the first lens unit moves along a locus convex toward the image-plane-side, the second lens unit moves toward the image-plane-side, and the stop moves; at the telephoto end compared with the wide angle end, an interval between the first lens unit and the second lens unit increases, an interval between the second lens unit and the third lens unit decreases, and an interval between the aperture stop and the third lens unit decreases, focal lengths of the fourth lens unit, a focal length of an entire system at the telephoto end, and a movement amount of the first lens unit are appropriately set.

Abstract: A photographic lens includes, in order from an object side to an image side, a first lens unit having a negative refractive power, a second lens unit having a positive refractive power, a stop, and a third lens unit having a positive refractive power. In the photographic lens, the third lens unit moves towards the object side while the second lens unit moves towards the image side during focusing from an infinitely distant object to a closest distance object. In addition, in the photographic lens, an image forming magnification of the second lens unit during focusing on a closest distance object is appropriately set.

Abstract: Provided is a zoom lens including, in order from an object side to an image side: a positive first lens unit without moving for zooming; a negative second lens unit moving during zooming; a negative third lens unit moving during zooming; a positive fourth lens unit moving during zooming; and a positive fifth lens unit without moving for zooming, in which the second lens unit moves to the image side during zooming from a wide angle end to a telephoto end, while the third lens unit moves along a locus convex toward the object side, and, when fw denotes a focal length of the entire system at the wide angle end, Z a zoom ratio, and fz a focal length of the entire system at a zoom position where the third lens unit is in the position closest to the object side, the following conditional expression is satisfied: fw×Z0.07<fz<fw×Z0.5.

Abstract: A zoom lens includes a first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power, and a fourth lens group having a positive refractive power, which are disposed in order from an object side, and an aperture stop disposed at an object side of the third lens group. When changing the magnification from a wide angle end to a telephoto end, an interval between the first and second lens groups increases, an interval between the second and third lens groups decreases, and an interval between the third and fourth lens groups increases. The first lens group includes a negative lens, a positive lens, and a positive lens, in order from the object side. Predetermined conditions of a refractive index of the negative lens E1 for a d line, an Abbe number for d line, and a relative partial dispersion are satisfied.

Abstract: An electro-optical display includes colorant particles that are suspended in a carrier fluid. The colorant particles are controlled by three different types of electrodes. An exposed electrode acts on the colorant particles in an electrokinetic manner by compacting the colorant particles. A passivated electrode acts on the colorant particles in an electrostatic manner by holding the colorant particles once compacted. A reference electrode attracts the colorant particles to compaction areas.

Abstract: In a camera module 1 of the present invention, a mechanical shutter 2 is provided above a top surface of a lens unit 3, and a protrusion section formed to an end of a lens 31 is held in a depression section formed on a back surface of the mechanical shutter 2. With the arrangement, it is possible to cause the camera module 1 employing the mechanical shutter 2 to be smaller and thinner at the same time.

Abstract: The thermally switched absorptive optical shutter may be a self-regulating “switchable absorber” device that may absorb approximately 100% of incoming light above a threshold temperature, and may absorb approximately 50% of incoming light below a threshold temperature. The shutter may be formed by placing a thermotropic depolarizer between two absorptive polarizers. This control over the flow of radiant energy may occur independently of the thermal conductivity or insulation of the shutter device and may or may not preserve the image and color properties of incoming visible light. This has energy-efficiency implications as it can be used to regulate the internal temperature and illumination of buildings, vehicles, and other structures without the need for an external power supply or operator signals. It also has aesthetic implications since the shutter device has unique optical properties that are not found in traditional windows, skylights, stained glass, light fixtures, glass blocks, bricks, or walls.

Abstract: Large aperture optical systems that are extremely well corrected over a large flat field and over a large spectral range are disclosed. Breathing and aberration variation during focusing are optionally controlled by moving at least two groups of lens elements independently. Aberration correction in general is aided by allowing the working distance to become short relative to the format diagonal. Field curvature is largely corrected by a steeply curved concave surface relatively close to the image plane. This allows the main collective elements to be made of low-index anomalous dispersion materials in order to correct secondary spectrum. In wide-angle example embodiments, distortion may be controlled with an aspheric surface near the front of the lens.

Abstract: A phase-adjusting element configured to provide substantially liquid-invariant extended depth of field for an associated optical lens. One example of a lens incorporating the phase-adjusting element includes the lens having surface with a modulated relief defining a plurality of regions including a first region and a second region, the first region having a depth relative to the second region, and a plurality of nanostructures formed in the first region. The depth of the first region and a spacing between adjacent nanostructures of the plurality of nanostructures is selected to provide a selected average index of refraction of the first region, and the spacing between adjacent nanostructures of the plurality of nanostructures is sufficiently small that the first region does not substantially diffract visible light.