Abstract: A tele-side converter lens including a first unit having a positive refractive power and a second unit having a negative refractive power, in which: the first unit includes one or two positive lenses; the second unit includes one negative lens and one or two positive lenses; and average Abbe constant and partial dispersion ratio of materials of positive lenses constituting the first unit, average Abbe constant and partial dispersion ratio of materials of positive lenses constituting the second unit, an Abbe constant and a partial dispersion ratio of materials of the negative lenses constituting the second unit, combined Abbe constants of materials of the lenses constituting the respective first and second units, focal lengths of the first and second units, a refractive index of a material of a positive lens disposed closest to the object side, and a magnification of the tele-side converter lens are appropriately set, respectively.

Abstract: A display panel includes a panel section having a display area in which a plurality of display pixels are two-dimensionally disposed and a ring-like frame area provided at the periphery of the display area, and a barrier section that is disposed at a position opposed to the panel section and has a barrier pattern composed of a light blocking area and a light transmissive area. Both the light blocking area and the light transmissive area are disposed in a first area opposed to the display area and a ring-like second area opposed to the frame area.

Abstract: Systems and methods are provided for monitoring eye movements of a user, and diagnosing and treating eye conditions substantially in real-time. A visual display device is provided with optical display fields corresponding to eyes of the user, and a controller linked to the device is programmed to measure eye positions with respect to the display device and determine optical deviations in any eye with respect to a central visual axis of the other (dominant) eye. In response to deviations exceeding a first value, an occlusion spot is generated in the display field for the dominant eye of a size corresponding to the degree of optical deviation. The location of the occlusion is continuously adjusted in accordance with real-time movements of the dominant eye based on the received signals from the device. When the optical deviation falls below a second value, occlusion of the dominant eye is disabled.

Abstract: A zoom lens includes an aperture diaphragm, and a plurality of lens units including a negative lens unit arranged on a light incident side of the aperture diaphragm, the zoom lens being configured to make variable a focal length by changing an interval in the plurality of lens units. The negative lens unit includes a negative lens having a radial type refractive index distribution and a concave surface on the light incident side. The negative lens has a wavelength dispersion distribution in which a differential value is negative on an optical axis of the zoom lens, and the differential value increases at a position that is more distant from the optical axis.

Abstract: The present invention discloses a screw-free connection structure for a frame and temples of eyeglasses. The eyeglasses are assembled primarily by a frame, two connection blocks, two elastic elements and two temples, wherein two temples are connected with a left and right end of the frame by the connection blocks, so that the temples and the frame can be connected together rapidly and securely without locking with screws.

Abstract: A polarization switching apparatus has a first birefringent polarizer formed as a composite prism and disposed to direct incident light of a first polarization along a first optical path and light of a second polarization along a second optical path, wherein the second optical path is oblique to the first optical path. A beam redirector is disposed to redirect the first optical path from the first birefringent polarizer toward an input face of a second birefringent polarizer; wherein the second birefringent polarizer is also formed as a composite prism and is disposed to combine incident light of the first and second polarizations onto a common output path. A shutter apparatus is actuable to selectively block light of the first polarization or light of the second polarization from the input face of the second birefringent polarizer.

Abstract: An optical lens assembly for image taking includes a first lens element, a second lens element, a third lens element and a fourth lens element. The first lens element with positive refractive power includes a convex object-side surface at a paraxial region. The second lens element with negative refractive power includes a concave object-side surface at a paraxial region. The third lens element with refractive power includes a concave object-side surface at a paraxial region and a convex image-side surface at a paraxial region. The fourth lens element made of plastic with negative refractive power includes a concave object-side surface at a paraxial region and an image-side surface. At least one of the object-side surface and the image-side surface of the fourth lens element is aspheric, and the image-side surface of the fourth lens element is concave at a paraxial region and convex at a peripheral region.

Abstract: An imaging lens includes a first lens having negative refractive power; a second lens having positive refractive power; a third lens having positive refractive power; and a fourth lens having negative refractive power, arranged from an object side to an image plane side. In the first lens, a curvature radius of an image-side surface is positive. In the second lens, curvature radii of the object-side surface and the image-side surface are both negative. In the third lens, a curvature radius of the object-side surface is positive and a curvature radius of the image-side surface is negative. When a whole lens system has a focal length f and the first lens has a focal length f1, the imaging lens satisfies the following conditional expression: ?3.0<f1/f<?1.

Abstract: An optical image capturing lens system includes, in order from an object side to an image side, a first lens element, a second lens element, a third lens element and a fourth lens element. The first lens element with positive refractive power has a convex object-side surface. The second lens element has negative refractive power. The third lens element has positive refractive power, wherein an object-side surface and an image-side surface of the third lens element are aspheric. The fourth lens element with refractive power is made of plastic material and has a concave image-side surface, wherein an object-side surface and the image-side surface of the fourth lens element are aspheric, and the fourth lens element has at least one inflection point formed on at least one of the object-side surface and the image-side surface thereof.

Abstract: A lens barrel includes a barrel wall disposed about a longitudinal axis, an external thread continuously formed on the barrel wall and having a continuous crest, and two parting lines that are longitudinally formed on the external thread and that are symmetrical about the longitudinal axis. A projection of the crest of the external thread on a plane orthogonal to the longitudinal axis has a maximum diameter and a minimum diameter. A difference between the maximum and minimum diameters is between 0.04 mm and 0.18 mm. Each of the two parting lines is disposed on portions of the external thread that define the minimum diameter.

Abstract: A photographing lens assembly includes, in order from an object side to an image side, a first lens element, a second lens element and a third lens element. The first lens element with positive refractive power has an object-side surface being convex at a paraxial region. The second lens element with negative refractive power has an object-side surface being concave at a paraxial region and an image-side surface being concave or planar at a paraxial region, wherein the second lens element is made of plastic material and the surfaces thereof are aspheric. The third lens element with negative refractive power has an object-side surface being concave at a paraxial region, and an image-side surface being concave at a paraxial region and being convex at a peripheral region, wherein the third lens element is made of plastic material, and the surfaces thereof are aspheric.

Abstract: A photographing system includes, in order from an object side to an image side, a first lens element, a second lens element, a third lens element, a fourth lens element and a fifth lens element. The first lens element with positive refractive power has a convex object-side surface. The second lens element has negative refractive power. The third lens element with positive refractive power is made of plastic material and has a convex object-side surface and a convex image-side surface. The fourth lens element with negative refractive power is made of plastic material and has a concave object-side surface and a convex image-side surface. The fifth lens element with refractive power is made of plastic material and has a concave image-side surface, wherein the fifth lens element has at least one inflection point. The object-side surfaces and the image-side surfaces of the third through fifth lens elements are aspheric.

Abstract: An assembly of an optical lens and an eyeglass frame is revealed. The assembly mainly includes a fastener mounting into and locked between a middle part of the eyeglass frame and a middle part of the optical lens, where the eyeglass frame and the optical lens mounted with each other. Moreover, a stopping plate is mounted into the eyeglass frame at the position corresponding to the fastener. By the stopping plate locked with the fastener, the fastener will not separate from the eyeglass frame. Therefore the connection between the eyeglass frame and the optical lens becomes more firmly and stably by the fastener.

Abstract: A photographing lens assembly includes, in order from an object side to an image side, a first lens element, a second lens element and a third lens element. The first lens element with positive refractive power has an object-side surface being concave at a paraxial region thereof and an image-side surface being convex at a paraxial region thereof. The second lens element has positive refractive power. The third lens element with negative refractive power made of plastic material, and has an image-side surface being concave at a paraxial region thereof and being convex at a peripheral region thereof, wherein an object-side surface and the image-side surface of the third lens element are aspheric.

Abstract: An optical modulation device side lens group has different powers in the longitudinal direction and the lateral direction of a liquid crystal panel. Therefore, as the entire system of the optical projection system, the optical modulation device side lens group has different magnification in the longitudinal and lateral directions. Therefore, it is possible to make the aspect ratio of an image of the liquid crystal panel different from the aspect ratio of an image projected on a screen. That is, conversion can be performed on an aspect ratio. At this time, a distance p between each focus or a diaphragm and the screen SC side end surface of the optical modulation device side lens group satisfies the conditional expressions, so it is possible to achieve a predetermined or higher telecentricity in both states, that is, a first operating state and a second operating state.

Abstract: A head-up display apparatus forms a virtual image of a display image viewed from a viewpoint region by projecting the display image onto a projection face. The apparatus includes a screen member and an optical device. The screen member includes an image formation face that forms the display image. The optical device includes a reflection face, which receives and reflects the display image by the image formation face, to project onto the projection face. The image formation face includes, in a grid array, convex portions and concave portions, which are convex and concave from a virtual reference face and alternated with each other along x axis and y axis. A perpendicular line to the virtual reference face at any position of the image formation face passes through an outside of the reflection face of the optical device.