Abstract: Flashlights are provided with a mode of operation enabling switching at a thumb area of a human hand while retaining that flashlight with fingers of that human hand during switching of that flashlight at that thumb area. The flashlight has a battery barrel provided with a tail-end switch. That battery barrel is also provided with a reduced diameter portion spaced from that tail-end switch, and with a retention element projecting from that reduced diameter portion for engagement by at least one of the fingers of the human hand during switching of the flashlight at the thumb area.

Abstract: A battery-powered apparatus for holding and energizing an electric transducer, includes a hand-held battery housing carrying the transducer mount, and first and second internal battery contacts. A first external battery charge terminal is on the transducer mount, and a second external battery charge terminal is on a part of the battery housing, such as its end cap. A double-throw switch has a common element electrically connected to an internal battery terminal contact, has a first switched contact leading to a first terminal of the electric transducer, and has opposite second switched contact electrically connected to an external battery charge terminal. If there are two electric transducers, they may be a part of a light source comprising a reflector, a first electric lamp having a filament at its focal point, and a second electric lamp extending into that reflector beside the first electric lamp.

Abstract: An aim assistance light beam is provided for a firearm having a barrel and a movable fore-end assembly for loading shells and actuating a firearm action. A lamp and reflector throws that light beam upon electric energization of a lamp in the lamp and reflector assembly. A battery housing for mounting that lamp and reflector assembly is below the barrel and is in the form of a hand grip for manual actuation of the fore-end assembly. That battery housing is mounted on the fore-end assembly for manual actuation of the fore-end assembly with that battery housing which also contains the battery for electrically energizing the lamp.

Abstract: An aim assistance light beam for a firearm having functional parts necessary for the operation of that firearm as a firearm is provided by adaption of a battery housing to a contour of that firearm below a barrel and ahead of a trigger guard thereof as seen in a direction of the light beam, for reception of an electric battery remotely from a stock of the firearm. A common fastener is provided for that battery housing as well as for one of the necesary functional parts of the firearm, and both that battery housing and that one necessary functional part are attached with that common fastener to the firearm. A light source is mounted on that battery housing for providing an aim assistance light beam upon energization from the battery through an electric on-off switch provided independently of any trigger and hammer assembly of the firearm.

Abstract: Methods and apparatus for releasably locking or blocking a door combine a first element with that door for blocking the door in an extended position of that first element and for alternatively releasing the door upon movement of the first element from such extended position. The first element is releasably blocked in its extended position by removably locating a second element in a path of movement of the first element. The door may be locked by locking the first element in its extended position and blocking such locked first element with the second element. The locked first element is released by selectively removing the second element from the path of movement of the first element, and the door is released by moving the released locked first element in its path of movement while the second element is removed from such path of movement. The first element may selectively be unlocked while it is blocked by the second element, and such blocked unlocked first element may be removed for a release of the door.

Abstract: In an effort to condition a battery for its current supply function, the electric charge required to restore the battery from a given first level to a higher second charge level is determined. A conditioning operation is comprised of a first step of reducing an unknown electric charge in the battery to the given first level, and a second step of introducing only the determined required electric charge into the battery. The battery is conditioned by administering in sequence the first step to reduce the unknown electric charge to the given first level and the second step to restore the battery to the higher second charge level by introduction of only the determined required electric charge into the battery.

Abstract: A firearm has a firing device, a manually cockable and selectively releasable hammer for actuating the firing device and a selectively activable laser beam emitting device for providing an aiming mark on a target of the firearm. The laser beam emitting device is activated through cocking of the hammer to provide the aiming mark. The cocked hammer is released with a finger trigger for actuation of the firing device only after activation of the laser beam emitting device and provision of the aiming mark.

Abstract: A laser for assisting the aiming of a firearm is located in a tubular member for emission of a light beam through an end thereof. The tubular member is mounted at the first location with linear freedom of movement, and at a second location with angular freedom of movement, relative to the firearm. The laser may be potted or rigidly mounted in the tubular member. A relative position of an aiming mark in the form of a light spot on a target of the firearm may be varied by angular adjustment of the tubular member at the first mounting location or by selectively deflecting the light beam in or at the tubular member.

Abstract: Laser apparatus having a pair of concave end mirrors facing each other through a laser gain medium. The end mirrors are mounted so as to permit tilting thereof. One of the end mirrors has a center of curvature situated between the end mirrors at a distance from the other end mirror of up to one-eighth of the distance between the end mirrors through the laser gain medium. The other end mirror has a center of curvature situated between the end mirrors at a distance from each of the end mirrors of at least three-eighth of the distance between the end mirrors through the laser gain medium. In practice, this substantially reduces the sensitivity of the laser apparatus and laser action to end mirror tilting and to bending of the laser gain medium or of a tube containing same. It also substantially increases the alignment tolerance and adjustability of the end mirrors and other parts of the laser structure and permits potting of gas lasers.