Abstract: An optical unit includes a first barrel, a second barrel, a third barrel, and a position detection unit. Eight magnets including first and second magnets are fixed to the first barrel. A first and second coils are fixed to the second barrel. The position detection unit includes a magnetic sensor configured to detect magnetic fields generated by the first and second magnets and to generate a detection signal having a corresponding relation with a position of the first barrel. The third barrel includes a position defining surface parallel to a moving direction of the first barrel. The position detection unit is fixed to the position defining surface.

Abstract: A camera optical lens includes, object side to image side, a first lens having positive refractive power, a second lens having positive refractive power, a third lens having negative refractive power, a fourth lens having positive refractive power, and a fifth lens having negative refractive power, and satisfies: 1.10?f1/f?1.50; 0.40?R3/R4?1.00; and 1.00?d5/d6?2.00, where f is a focal length of the camera optical lens, f1 is a focal length of the first lens, R3 is a central curvature radius of an object side surface of the second lens, R4 is a central curvature radius of an image side surface of the second lens, d5 is an on-axis thickness of the third lens, and d6 is an on-axis distance from an image side surface of the third lens to an object side surface of the fourth lens, thereby having a large aperture, a wide angle and ultra-thinness with good optical performance.

Abstract: The present disclosure discloses a camera apparatus including a first optical system and a second optical system. The second optical system includes a secondary reflecting mirror, a main reflecting mirror with an opening in a center area thereof, and a lens group, which are sequentially arranged from an object side to an image side. Light from the object side is sequentially reflected by the main reflecting mirror and the secondary reflecting mirror, and then enters the lens group through the opening. A total effective focal length F1 of the first optical system and a total effective focal length F2 of the second optical system satisfy: F2/F1>10.

Abstract: The present disclosure relates to the technical field of optical lens and discloses a camera optical lens satisfying following conditions: 65.00?v1?90.00; ?5.00?f2/f??1.50; 1.50?(R5+R6)/(R5?R6)?30.00; and ?6.00?R12/R11??1.20; where v1 denotes an abbe number of the first lens L1; f denotes a focal length of the camera optical lens; f2 denotes a focal length of the second lens; R5 denotes a central curvature radius of an object-side surface of the third lens; R6 denotes a central curvature radius of an image-side surface of the third lens; R11 denotes a central curvature radius of an object-side surface of the sixth lens; and R12 denotes a central curvature radius of an image-side surface of the sixth lens. The camera optical lens provided in the present disclosure satisfies a design requirement of large aperture, wide angle and ultra-thinness while having good optical functions.

Abstract: Provided is a camera optical lens, including, from object side to image side, a first lens having positive refractive power; a second lens having positive refractive power; a third lens having positive refractive power; a fourth lens having positive refractive power; a fifth lens having negative refractive power; a sixth lens; a seventh lens having negative refractive power; an eighth lens having positive refractive power; and a ninth lens having negative refractive power. The camera optical lens satisfies 3.50?f1/f?5.00 and 2.50?d3/d4?10.00, where f denotes a focal length of the camera optical lens, f1 denotes a focal length of the first lens, d3 denotes an on-axis thickness of the second lens, and d4 denotes an on-axis distance from an image side surface of the second lens to an object side surface of the third lens. The lens has large aperture, wide angle and ultra-thinness while having good optical performance.

Abstract: A lens 1 has unevenness within an optical effective diameter D of an optical surface 2, an arithmetic mean roughness Ra within the optical effective diameter D of the optical surface 2 is 20 nm or more and 50 nm or less, and an average value of widths W of protrusion portions 3 of the unevenness on an average line C2 of a roughness curve C1 of the optical surface 2 is 1/200 or more and 1/50 or less of the optical effective diameter D of the optical surface 2. The lens 1 is suitably used as a lens that composes a zoom lens or an imaging lens.

Abstract: A camera optical lens includes first to fifth lenses that are sequentially arranged from an object side to an image side. Each of the first lens, the third lens, and the fourth lens has a positive refractive power, and each of the second lens and the fifth lens has a negative refractive power. The camera optical lens satisfies: 0.50?f1/f?0.80; ?1.20?f2/f??0.70; 1.50?d8/d9?3.00; ?1.50?R3/R4??0.60; and 1.20?R7/R8?2.00, where f denotes a focal length of the camera optical lens; f1 denotes a focal length of the first lens; f2 denotes a focal length of the second lens; and d8 denotes an on-axis distance from an image-side surface of the fourth lens to an object-side surface of the fifth lens. The camera optical lens can achieve high optical performance while satisfying design requirements for being ultra-thin and having a wide-angle and a large aperture.

Abstract: A camera optical lens is provided. The camera optical lens includes, from an object side to an image side, a first lens, a second lens having a negative refractive power, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, and a ninth lens. The camera optical lens satisfies following conditions: 2.00?f1/f?5.50; and 2.00?d7/d8?10.00, where f denotes a focal length of the camera optical lens, f1 denotes a focal length of the first lens, d7 denotes an on-axis thickness of the fourth lens, and d8 denotes an on-axis distance from an image side surface of the fourth lens to an object side surface of the fifth lens. The camera optical lens according to the present disclosure satisfies design requirements for large-aperture, wide-angle, and ultra-thin lenses while achieving good optical performance.

Abstract: Endpiece assemblies for eyeglass frames and eyeglasses are shown and disclosed. In one embodiment, the endpiece assembly includes an elongate body having a channel partially defined by an elongate bottom wall of the elongate body. The elongate body adapted to be attached to, or formed with, a temple of the eyeglass frame. The endpiece assembly additionally includes an intermediate member having first and second end portions and a first central portion therebetween. The first central portion and the second end portion are received in the channel and the first end portion adapted to connect to a connecting bar of the frame front of the eyeglass frame. The endpiece assembly further includes a first plurality of magnets disposed within the channel.

Abstract: The present disclosure discloses an optical imaging lens assembly, and the optical imaging lens assembly includes, sequentially from an object side to an image side along an optical axis: a first lens having positive refractive power, and at least one subsequent lens having refractive power. An F-number Fno1 of the optical imaging lens assembly satisfies Fno1>3.5, where an object distance is finite, and an F-number Fno2 of the optical imaging lens assembly satisfies Fno2?1.0, where the object distance is infinite.

Abstract: A tube system for a microscope includes two lenses and a glass element. The tube system can have a compact build and chromatic aberrations that lie within a specified range.

Abstract: A musical instrument, comprising a neck and a body. A chord selector is present on the neck, and a note selector is present on the body. The chord selector comprises a plurality of locations, each having a tonic and a quality. The note selector is a touch sensitive strip that is linearly arranged like a piano keyboard. A note is sounded only if it is simultaneously pressed on the note selector, and is present in one of the chords selected on the chord selector. Thus, once a chord is selected, it may be picked, strummed, or arpeggiated by employing different hand motions upon the note selector.

Abstract: A decorative display device comprising figurines arranged in tiered first and second scenes, one scene being placed above the other. Each of the upper and lower tier scenes is coupled to a wind-up drive and music box mechanism and when rotated appears to be in synchronization with the music. The rotatable and music synchronized scenes are more noticeable and aesthetically pleasing and, thus, provide a more interesting display. The upper and lower tier scenes may rotate simultaneously, at different speeds (but in the same direction), in opposite directions, in opposite directions at different speeds, or one scene may rotate while the other scene remains stationary.

Abstract: A device for setting the tension of a skin, particularly one used in a musical instrument, such as a kettledrum. The device includes a freely-suspended multi-part linkage for vertically displacing a tensioning star, wherein the linkage has two parts connected through a pivot. Each of these link parts has first and second ends, where the first and second ends of the first and second link parts respectively form first and second ends of the entire linkage. The pivot lies inward on the first and second link parts of the second and first ends of the first and second link parts, respectively. Furthermore, the second link part bears, at a first predefined location thereon, such as proximate the second end thereof and via a contact face located thereat, against an adjustment cam. A coupling pin is connected to the second link part at a second predefined location intermediate the point where the pivot is connected to this link part and the first predefined location.

Abstract: A structural improvement for a conga drum stand including a ring-framed carrier having a round hole at its center and a number of balancing blocks extending radially from its rim with a hole extending between the trough and the channel of each balancing block. A positioning block, inserted into each of the troughs, includes a vertical locking hole in the bock base. The locking hole is penetrated by a locking component with a hexagonal nut at its bottom end in the channel. The positioning blocks are configured so that they can be easily positioned in the trough.

Abstract: The present invention is a practice chanter for simulating a bagpipe chanter. In its most basic form, the practice chanter of the present invention includes a flexible airtube, a fipple head attached to the flexible airtube, and a rigid whistle tube attached to the fipple head. In this basic embodiment, the whistle tube includes a plurality of holes disposed at predetermined locations along the length of the whistle tube corresponding to locations of holes in the predetermined bagpipe chanter, with each of the holes having a predetermined diameter such that the key and pitch of notes produced by the practice chanter correspond to notes produced by the bagpipe chanter. In the preferred embodiment, the practice chanter is dimensioned to simulate an Uilleann Pipe chanter.

Abstract: A snare mounting and tension adjusting arrangement includes a tension adjustment unit and a snare holder unit fastened to the peripheral wall of a snare drum to hold a snare under the snare head of the snare drum, wherein the tension adjustment unit includes a locating frame fixed to the snare drum at one side, a slide coupled to a rail at the locating frame, an adjusting screw bolt mounted in a through hole at the locating frame and threaded into a screw hole at the slide and rotated to lift/lower the slide along the rail in adjusting the tension of the snare, and a locking lever pivoted to the slide and controlled to lock the slide.

Abstract: An arrangement for protecting adjacently situated musical drums in a group or assemblage comprising an external tuning mechanism affixed to the side of the shell of at least one drum, including a tuning rod extending and attached to the head of the drum for varying the tension on the head, wherein the rod is received in a receptacle and a nut is secured to the end of the rod for varying the applied tension; a protector device including an engaging with the receptacle and positioned to extend beyond the limit of the tuning mechanism's radial protrusion beyond the shell periphery, thereby to prevent or preclude contact with another drum shell except by the protector.

Abstract: A low friction vented rotary valve for a brass instrument is disclosed comprising a partially circumferential member providing a low friction engagement with the rotary casing. The partially circumferential member has first, second and third apertures therein with a first tube connected between the first and second apertures and a second tube connected at one end of the circumferential member. The second tube has an arcuate collar at its other end for providing another low frictional surface engaging the rotor casing.

Abstract: A percussion bell support includes a base connected to the bell head end, a jaw swingably attached to the base, surfaces on the base and jaw to clamp to a support member, when the jaw is swung toward the base and head end of the bell, a connector shank passing through the jaw and into the base, and a handle, the jaw remaining between the handle and base during swinging of the jaw and during handle and shank rotation to tighten the jaw and base to the support member.