Abstract: A magazine for a firearm includes a body having a bottom end, a feed end side walls, first and second end walls, a channel on the first end wall, and vertically extending side ridges on the side walls; and a follower including a ridge configured to mate with the channel in the first end wall of the body; a plurality of vertically extending side channels configured to mate with the side ridges of the body; and an arcuate feed surface with an end point of a radius defining the arcuate feed surface being laterally offset from a vertically extending centerline of the follower; and a biasing member configured to urge the follower away from the bottom end.

Abstract: A magazine loader for a firearm is provided. The magazine loader includes a base having a lip that is configured to removably engage a magazine in an upstanding position thereon. The base further includes a hydraulic shaft having a first end and a second end, wherein the first end is affixed to the base. The second end includes a depressible platform and a projection configured to load an unloaded cartridge placed above an opening of a magazine. The depressible platform is configured to be hand actuated in relation to the hydraulic shaft to apply downward pressure on the unloaded cartridge with the projection. In this way, the cartridge can be forced downwardly and loaded into the magazine. The depressible platform and projection automatically return to the resting position to allow for additional cartridges to be loaded.

Abstract: Apparatus for authorizing and de-authorizing a device such as a weapon is disclosed. The apparatus includes the electrical detection of a signal on the skin of the user, and optionally a radio signal from a central authorizing authority and the entering of a security code by the user. Upon receipt of the correct input, the weapon authorizes and is ready for use. If a loss of skin signal occurs, the weapon enters a safe state until reauthorized. Apparatus for generating the skin signal from both an ingestible and a skin-mounted apparatus are disclosed.

Abstract: A training/safety plug for use in firearms is provided. In one implementation, the plug comprises a chamber end and a shaft extending away from the chamber end. The chamber end is adapted to fit within a chamber of a designated firearm, the chamber end has a cross-sectional dimension sufficient to prevent the chamber end from extending into a barrel of the designated firearm and further comprises a strike surface for receiving an impact of a firing pin of the designated firearm and a proximal end dimension such that the chamber end is not engaged by an ejector mechanism of the firearm. The shaft comprises a barrel end coupled to and extending distally from the generally cylindrical chamber end; the barrel end of the generally cylindrical shaft further adapted to extend from the chamber end into the barrel of the designated firearm.

Abstract: Methods and apparatus are provided for a semiautomatic rifle with a trigger in a receiver portion of the rifle positioned substantially forward of a back end of the rifle barrel, and a hammer assembly that includes a pivotally mounted sear, a disconnector, and a hammer mounted in the receiver behind the back end of the barrel. A hammer linkage proximate the hammer assembly has a first end connected to the trigger by a pull rod, and a second end configured to push a back end of the sear in an upward direction.

Abstract: A firearm is provided according to the present invention. The firearm can be a striker style firearm having a slide. A trigger contacts a sear block at the front of the striker to fire the firearm. The striker then moves rearward with the slide under operation of the recoil spring and then returns forward. A reset plunger engages the striker during the second part of this process to reset the striker. The trigger has a release lever which is allowed to rotate relative to the rest of the trigger when the striker is reset and the sear block moves the release lever to the rotated position. The release lever rotates back to the ready position as the trigger is released. A slide stop is also provided that is held in place under operation of the recoil spring.

Abstract: A suppressor for rapid fire weapons designed to rapidly bleed down the weapon pressure and thereby minimizing gas blowback to the operator and to the weapon's gas operating system; while also creating a shear gas flow about the exiting bullet's gas flow to mask the flash thereof. The suppressor is configured within a generally cylindrical housing, having: (1) a central core of unported K-baffles located about a central bulletway; (2) a bypass located between the cylindrical housing and the unported K-baffled central core—providing a generally forward subsonic high gas flow area to an endcap closing the cylindrical housing; (3) said endcap having a series of vent ports for the bypass, which also create a shear flow about the centrally exiting bullet; and (4) wherein the series of unported K-baffles are spaced away from the weapon's bore end to allow the propellant gasses to expand into the bypass.

Abstract: A disrupter unit is used for explosive ordnance disposal by firing a slug into the ordnance to be destroyed. A method is shown to secure the disrupter unit to a sand bag or other stationary location during such firing of the disrupter unit. The present invention may also adapt the disrupter unit to shear wire, such as barbed wire, by attaching a wire cutter element to the disrupter unit through a robust cable during firing. Likewise, the disrupter unit may be used as a remote pull device or further to unearth a buried item via mechanical advantage, wherein a military shovel or another long rod is attached by a robust cable to the disrupter unit.

Abstract: An at the ready weapon holder for supporting a pistol at its barrel, the at the ready weapon holder including a pistol bore support member including a substantially cylindrical rod having a top end and a bottom end and a base including a base plate and a receptacle for receiving the bottom end of the substantially cylindrical rod. The top end of the substantially cylindrical rod is adapted to removably secure the pistol at its barrel by having the top end of the substantially cylindrical rod inserted into the bore of the pistol.

Abstract: A pulley assembly for a compound bow comprises a draw cable pulley rotatable about a first axis, a mounting member attached to the draw cable pulley and adjustable among multiple positions, and a power cable pulley attached to the mounting member and adjustable among multiple positions about a second axis. Movement of the mounting member shifts the second axis relative to the first axis. Movement of one or both of the mounting member or power cable pulley alters one or more of the bow's draw force curve, draw length, draw weight, or stored energy.

Abstract: A crossbow device at least comprises a stock with a body portion, a track, and a aiming position member. A lower bow portion is arranged at the front of the body portion which includes a connection portion and a first screw hole is arranged thereinside. A bow frame is fastened in the track and assembled with the aiming position member. A second screw hole is formed at the front of each rod. A bow string set is assembled with the bow frame. Tow positioning blocks are protruded in the limit groove and a third screw hole is arranged at each positioning block and corresponding to the second screw hole. A fourth screw hole is arranged at a hook portion and corresponding to the first screw hole. The screw members are screwed in the third screw hole, the second screw hole, and the fourth screw hole of the hook portion.

Abstract: An apparatus for absorbing energy from the release of an archery bow. The apparatus of the present invention provides an elongated support structure releasably connectable to a vibration reduction insert. The vibration reduction insert has a substantially cylindrical shape and at least one substantially C-shaped recess along an outer edge of the vibration reduction insert. A releasable fastener is connected to one end of the support structure, and the fastener is releasably connectable to the archery bow such that the support structure is extendible in a cantilevered position relative to the archery bow. The vibration reduction insert may be made from a vibration reduction material. Along an edge of the C-shaped recess, the vibration reduction insert may have a U-shaped recess that extends toward the radial center of the vibration reduction insert. There may be two substantially C-shaped recesses that are substantially coaxially aligned.

Abstract: A rotary auger bow mounting stand for removably holding a bow upright on the ground. The stand includes an upright rod with a helical coil or flights forming an auger base having a point at the lower distal end to be fixedly and removably screwed into the ground to support the stand in an upright position. The top end of the rod forming the stand body defines an S-shaped loop configured, sized and shaped and disposed at a selected angle to support a the arm of a bow holding the bow in a substantially vertical position above the ground. The integral loop which supports the is bow forms a handle for the purpose of rotating the auger into the ground.

Abstract: A gear checked construction for a toy gun comprises a gun body, a piston, a driving gear, and a check assembly. The piston is mounted inside the gun body and a rack is formed on the bottom of the piston. The driving gear engages with the rack to drive the piston and includes a clamping part. The check assembly comprises a hinge and a check bar. The hinge is mounted inside the gun body and the check bar is set around the hinge and comprises a forward part and a reverse part. The clamping part touches on the forward part and bursts through the check bar when the driving gear rotates in one direction to drive the piston, and the clamping part engages with the reverse part to stop the driving gear's rotation when the driving gear rotates in the other direction.

Abstract: A toy launch apparatus for discharging soft foam darts, the launch apparatus having a cylinder, a piston, a launch spring, a dart magazine and a dart tube. The dart tube is biased by a return spring so that after a dart discharge the dart tube is moved rearward from a launch chamber to allow the magazine to spring load a fresh dart. During a cocking cycle the dart tube moves forward and receives the dart so that loading of a second dart is blocked. The automatic withdrawal of the dart tube after discharge of a dart also allows an empty magazine to be disengaged from the launch apparatus and a freshly loaded magazine to be attached. This may be accomplished without an operator having to take any other action thereby resulting in a very quick reload.

Abstract: In a firing switch of the single/continuous firing air soft gun, the air soft gun includes a gun body and a barrel fixed in the gun body, and the firing switch includes a piston seat and a firing switch device, wherein the piston seat is disposed in the gun body and capable of reciprocally moving in horizontal with respect to the barrel; and the firing switch device is installed on the piston seat, and includes a stop piece and a toggle piece connected with the stop piece, and the stop piece is disposed corresponding to the trigger assembly.

Abstract: A firearm comprising a barrel, a handguard disposed around the barrel; a manually operated pump-action reload mechanism, the pump-action reload mechanism comprising a hand-held actuation arrangement and a fore-end body, the fore-end body disposed around the barrel between the handguard and the barrel, and the hand-held actuation arrangement coupled to the fore-end body to operate the pump-action reload mechanism. In addition, or alternatively, the firearm may include a bolt carrier locking mechanism and/or a butt stock that may be folded on either side of the receiver.

Abstract: A modified bolt carrier for automatic recoil rifles and pistols preferably includes a modified bolt carrier, a folding stock member, a shortened buffer tube, an end cap, a butt stock threaded tube and a bolt carrier sleeve. A sleeve bore is formed in the modified carrier bolt to receive the bolt carrier sleeve. The folding stock member includes a swing base and a swing arm. A tube bore is formed through the swing base to receive the shortened buffer tube. Upper and lower flanges extend from the swing base to retain a pivot pin. The swing arm includes a butt pivot arm, which extends from the stock ring. The pivot arm is pivotally retained on the swing base with the pivot pin. The butt stock threaded tube is threaded into the stock ring. The end cap includes an end cap portion and a guide rod.

Abstract: An automatic adjustable buttstock system for a small arms weapon including a buttstock and a pair of parallel rails adapted to slidably mount the buttstock on a body of the weapon, each rail having a plurality of female locking slots along its length. A lock block is employed having a pivotable spring-loaded locking lever and a pair of locking tabs adapted to engage the female locking slots disposed along the length of each rail. A volute spring disposed between a rear wall of the lock block and a cavity in the buttstock is adapted to rearwardly bias the buttstock towards a fully extended position. The locking lever is adapted to be pivoted to disengage the pair of locking tabs from the female locking slots for displacement of the buttstock between a fully shortened configuration, in which the volute spring is fully compressed, to the fully extended position as urged rearwardly by the volute spring.

Abstract: A arm stabilizer configured with a stretchable elastic member having a first end and a second end, an adjustable shoulder sling hingedly connected to the first end of said stretchable member, and a fixed hand sling hingedly connected to the second end of the stretchable member and, thus configured to be worn by a marksman with an extended aiming and firing arm and is not affixed to the firearm, is light in weight, easy to transport, and quick installation enables stabile aiming and firing accurately at a target.

Abstract: Holster mechanism techniques are described. In one or more implementations, an apparatus comprises a holster configured to secure a device, a hood connected to the holster, and a locking mechanism. The hood comprises a biasing portion configured to receive a force to cause the hood to move between a closed position and an open position. The locking mechanism comprises a first locking portion and a second locking portion configured to engage the first locking portion to secure the hood in the closed position or the open position.

Abstract: An electro-optic system, e.g., mounted to a weapon, measures down range winds and a range-to-target for compensating the ballistic hit point. The system may include an optical light source, collimated to generate a laser spot on the target. The system may include a wind measurement receiver that captures laser light scattered from the target. The captured light may be modulated by atmospheric scintillation eddies, producing optical patterns which change in time and move with the crosswind. These patterns may be analyzed by a processor using covariance techniques in either the time-domain or the frequency-domain to determine path-integrated crosswinds and associated errors. Ranging is done by measuring the time of flight of the laser pulse to the target collecting the scattered signal from the target.

Abstract: An offset aperture two-axis gimbaled optical system comprises a two-axis gimbal and an optics assembly that is mounted on the inner gimbal and offset radially from the rotation axis of the outer gimbal. The optics assembly is suitably offset so that its optical aperture does not overlap the rotation axis of the outer gimbal and its optical aperture is symmetric about the rotation axis of the inner gimbal. In different applications, the offset aperture provides for reduced optical aberrations and improved utilization of the available packaging volume to accommodate multiple offset aperture optics assemblies.

Abstract: Camouflage articles are formed of arrangements of portions of different colors. The lighter colored portions or parts thereof are formed of reflective ink in that particular color. This arrangement provides the article with a camouflage appearance, altering depth perception by animals in daylight, and reflectivity at night for safety.

Abstract: A multilayer armored panel comprising: (I) at least one layer that is non moldable when dry but moldable when wet; (II) at least one hydrogel based layer in contact with layer (I) which, when wet enables the molding of layer (I) but which is capable of drying out to leave a non moldable layer (I).

Abstract: An armor system that includes a first armor article that includes a plurality of energy-dispersion objects arranged in a predetermined configuration, wherein the plurality of energy-dispersion objects includes a plurality of hollow objects, and wherein at least some of the plurality of hollow objects are filled with an inner filler material; and a lock mechanism configured to hold the plurality of energy-dispersion objects in the predetermined configuration. A method for manufacturing an armor system, the armor system including a first armor article, the method including producing a plurality of hollow hemispheres; affixing pairs of the plurality of hemispheres to one another to form a first plurality of spheres; treating each one of the plurality of hemispheres with an anti-ballistic treatment; inserting a filler material into each one of the plurality of hemispheres; and locking the first plurality of spheres into a predetermined configuration.

Abstract: A ballistic shield may include multiple ballistic plates. The first plate may be permanently connected to a second plate and drop vertically downward from the first plate. After dropping down, the second plate would overlap the first plate such that no gap exists between the two plates. A third plate may similarly drop with respect to the second plate. Side folding ballistic plates may be attached to the first and second plates to lock them in position and provide ballistic protection to the sides of the user. These side ballistic plates may overlap the first and second plates. The side plates can have another ballistic plate mounted on their unconnected ends such that another assembly of first, second and side ballistic plates identical as above may also be connected. After connecting this second assembly, the user(s) would have full 360 degree ballistic coverage.

Abstract: A mobile ballistic defense shield with enhanced protection for a user includes a base frame with swivel castors to contact a ground surface, a ballistic main plate with at least one shooting port and a viewing port, the ballistic main plate affixed to the base frame and oriented to enable the main plate to extend upward from the ground surface, a ballistic foot plate pivotably mounted to a bottom portion of the ballistic main plate, and a handle affixed to the ballistic foot plate and connected to a support assembly affixed to the base frame. The handle adjusts to a first position to enable the ballistic foot plate to contact the ground surface. The handle adjusts to a second position to enable the ballistic foot plate to pivot away from the ground surface, thereby permitting the base frame to travel along the ground surface.

Abstract: The present invention includes self-defense apparatus comprising a wristband, an upper compartment with a circular recess attached to the wristband, and a clasp system. The upper compartment holds a small cylindrical canister containing a self-defense spray, the nozzle of the canister aligns with the circular recess. The wristband is comprised of an inner end and an outer end. The clasp system is comprised of an outer portion and an inner portion, wherein the outer portion is located on the outer end of the wristband, and the inner portion located on the inner end of the wristband. The outer portion of the clasp system attaches to the inner portion of the clasp system.

Abstract: The invention relates to a method for determining angle of incidence for a projectile in the path of the projectile from launcher to target, which projectile is guidable and substantially or partially roll-stable and comprises a control system and at least two actuators with associated control members, in which the following steps are included: determination of applied force for pitch control by evaluation of the moment upon the actuators of the projectile, determination of applied force for yaw control by evaluation of the moment upon the actuators of the projectile, calculation of the pitch component a of the angle of incidence and of the yaw component ? of the angle of incidence, based on comparison between the evaluated moments and reference data for moments. The invention also relates to a GNC system.

Abstract: A mechanical broadhead device which includes a plurality of blades pivotably attached to a shaft, where the plurality of blades and the shaft are disposed within a tapered cover, and an arrow comprising the mechanical broadhead device attached to an arrow shaft has an aerodynamic profile in flight that mimics an aerodynamic profile of an arrow comprising a target or field point.

Abstract: According to the invention, the rear part of the connecting element (1), which part is intended to be connected to a body (4) made of composite material, comprises at least one abutment (13) of annular shape, centered with respect to a longitudinal axis (10) and intended to come into contact with the front edge (14) of said body (4), and a longitudinal rearward extension (15) which is defined from said abutment (13) onward and which comprises a contact face (16) and has a shape and diameter suited to said body (4) so that its contact face (16) can come laterally into contact with a peripheral surface (17) thereof.

Abstract: A method of manufacturing a low observable photoluminescent tracer projectile, for use with a small caliber weapon at night—which method utilizes a base phosphor material of Ca, Sr and S, or a base phosphor material of Y2, O2, and S—with a combination of minor dopant ingredients; which base phosphor material is mixed with a clear binder to form a photoluminescent material which is applied to the rear end, or base, of a small arms projectile as a thin layer; to which thin layer is added a layer of small retro-reflectors—whereby, when this projectile is fired from the weapon, the photoluminescent mixture will be activated and will be observable, using night vision at an angle of 0 to about 20 degrees from the rear end of the projectile.

Abstract: A munition has a fuze that is mounted nonparallel to the axis of the munition, for example having a largest extent that is perpendicular to the longitudinal axis of the munition. Shocks from the fuze are transferred through a shock transfer device that is in contact with the fuze, to an initiation device that is also in contact with the shock transfer device. Shocks passing through the shock transfer device to the initiation coupler pass through a relatively narrow neck of the shock transfer device. In the shock transfer device the shock is concentrated and located precisely at the neck, before spreading out again and being transferred to the initiation device. In the initiation device the shock may detonate a high explosive material, which in turn is used to detonate a main explosive of the munition, such as a warhead.

Abstract: A detonator system is provided for use with explosives that utilizes two subsystems. A first subsystem functions as a non-explosives based detonator, which does not contain any explosives. The second subsystem is an initiating subsystem, which includes an initiating pellet. To set off an explosive event, the non-energetics based detonator is coupled to the initiating subsystem and the non-energetics based detonator is commanded to provide a suitable signal to the initiating subsystem that is sufficient to function the initiating pellet. Further, the initiating subsystem can be integrated directly into an associated explosive such as a booster that has been configured to receive the initiator subsystem without changing the hazard class of the booster.

Abstract: The invention comprises a device and method of using said device(s) including but not limited to; Long Range Acoustical Devices (LRAD), Hyper Sonic Sound (HSS), Cascaded Linear Array Systems (Clas and BClas) and or HyperSpike devices currently and typically used for sonar, acoustic hailing, crowd control, mass notification, and sonic boom simulation—to initiate avalanche release in or in proximity to avalanche corridors and starting zone(s) as a non-explosive control alternative. The invention is an integration of technologies incorporating an infrasound generator, on board power supply and amplification, inverter, digital signal processor, GPS, and RF receiver all housed in a rugged weather resistant enclosure with necessary gantry and rigging. The combination of these technologies allows control personnel to safely operate the equipment from a remote location. The invention is deployed remotely via a cable or network of cables to predetermined avalanche starting zone(s).

Abstract: A compliant wheel assembly is provided for moving a caliper jaw relative to a caliper spar. The wheel assembly includes a rotary bearing member, a rotary actuation member and a compliant coupling element. The rotary bearing member is coupled to the caliper jaw and may engage the caliper spar. The rotary actuation member is actuated by a user to apply a measuring force. The compliant coupling element is configured to compliantly couple the rotary actuation member to the rotary bearing member. Using the compliant wheel assembly, a user is able to apply a more consistent amount of measurement force than could typically be achieved with a conventional rigid thumb wheel in caliper. In one implementation, a displacement indicator may also be provided that is responsive to the rotational displacement between the rotary bearing and actuation members for indicating an amount of measurement force that is being applied.

Abstract: A dent measurement apparatus is presented. The dent measurement apparatus may be used in conjunction with documenting damage in objects, such as vehicles. Such damage may include dents, and the documentation process may include images or videos. To convey detail, it may be desirable to focus the images or videos closely on a damaged region and, in such cases, the dent measurement apparatus may help provide context for the size and depth of the damage. In particular, the dent measurement apparatus may removably attach to and extend from the damaged area such that the depth of damage may be determined relative to one or more markings on the body of the dent measurement apparatus.

Abstract: A method to fixture and inspect contoured aerodynamic surfaces of a part, such as an engine inlet lip skin, is provided. A controlled preload is applied to one or more discrete locations along the contoured surface to constrain the lip skin at the locations the lip skin would be constrained upon assembly on the airplane. The contoured surfaces are then inspected to dimensional requirements. The controlled preload can be applied by use of magnets or elastic bumpers.

Abstract: A combination gauge tool and a method of measuring are provided. The combination gauge tool includes a processing module having a sensor. The combination gauge tool includes at least two of a brake pad thickness gauge, a tire treads depth gauge, and a rotor thickness gauge each coupled to the processing module at one or more inputs of the sensor and configured to provide measurement data to the sensor.

Abstract: A two way roundness device can be configured as a device in which a tool, such as an indicator rotates or as a device in which the part to be measured or cut rotates. This ability to alternate between these two configurations is enabled by a combination of a rotating spindle assembly and a two-axis stage that can be oriented, in use, with the two-axis stage under the spindle assembly or with the two-axis stage on top of the spindle assembly.

Abstract: Disclosed is a near-surface object sensing device, including a printed circuit board, a plurality of magnetic sensors arrayed on the printed circuit board to sense the magnetic field of an external magnetic object and generate a magnetic sensing signal, a multiplexer connected to the magnetic sensors for selecting and outputting the magnetic sensing signal, and a microprocessor connected to the multiplexer for receiving the magnetic sensing signal, wherein the microprocessor includes a sampling algorithm module for converting the magnetic sensing signal into a magnetic field distribution image, and a six-dimensional coordinate-calculating module for calculating six-dimensional coordinates of the external magnetic object. The sensing device of the invention is compact, low energy consuming and can accurately provide users with a convenient and intuitive user interface with three dimensional locations and position information in a near-surface space.

Abstract: A hydraulic cylinder stroke operation diagnosis assisting device includes: movable portions that are sequentially supported by a vehicle body in a rotatable manner; a hydraulic cylinder between the vehicle body and each movable portion or between the movable portions to support the movable portions in a rotatable manner; a stroke sensor in the hydraulic cylinder to measure a stroke length of the hydraulic cylinder; a reset sensor measuring a reference reset point in which a value of the stroke length measured by the stroke sensor is reset; a stroke end detection unit detecting a stroke end position of the hydraulic cylinder; a calibration unit calibrating the measured value of the stroke length when the reference reset point and/or the stroke end position are detected; and a monitor displaying at least the measured value of the stroke length and a calibration state by the calibration unit.

Abstract: A sensor assembly having a pair of sensors and a pair of sensor targets. Each of the sensors is an eddy current sensor that defines X, Y and Z axes that are orthogonal to one another such that the X-axes are aligned to a movement axis along which a structure is to be moved. The sensor targets are coupled to one another for common movement and are formed of an electrically conductive material that is configured to interact with a respective one of the eddy current sensors to cause the sensors to produce sensor signals that each vary in a distinct manner with movement of the targets parallel to the movement axis. The targets are configured such that their coordinated movement in a direction parallel to the Z-axes as they are moved along the movement axis has no effect on the determined location of the structure. A method is also provided.

Abstract: The present invention relates to distributed computing system to acquire, process, and display OCT images at real-time frame rates.

Abstract: A method of supporting an item in a mounting apparatus includes providing an item having first, second, and third members that are at least partially-spherical. The method additionally includes supporting the first member with a first mount configured to constrain the first member against movement along three mutually-orthogonal directions. The method also includes supporting the second member with a second mount configured to constrain the second member against movement along exactly two of the directions, and supporting the third member with a third mount configured to constrain the third member against movement along exactly one of the directions.

Abstract: A spherically mounted retroreflector (SMR) having a reference point placed on a body of the SMR in a fixed and predetermined relationship to a runout error vector as given in a manufacturer's data sheet. A method for aligning the reference point to minimize measurement error.

Abstract: A system for monitoring, in real time, relatively large samples as they are caused to pass by an ellipsometer or the like system, and method of its use.

Abstract: An embodiment of the present invention provides a method for aligning a phase retardation plate with a display panel comprising the following steps: S1: determining the positions of a first reference line on the phase retardation plate and a second reference line on the display panel, wherein the first reference line is the central line between the first and second ends of the phase retardation area, and the second reference line is the central line between the third and fourth ends of the display area; S2: obtaining a positional deviation between the first reference line and the second reference line by calculation; S3: adjusting the relative position between the phase retardation plate and the display panel according to the positional deviation.

Abstract: A method for verifying a size of an energy beam spot, said method comprising the steps of providing a first beam spot having a predetermined size and power at a first position on a work piece, varying a focus and/or astigmatism lens setting for said first beam spot until max intensity for the beam spot is detected, comparing the detected settings of said focus lens and/or astigmatism lens for said maximum intensity of the beam spot with stored settings of said focus lens and/or astigmatism lens for the beam spot with said predetermined size and power, repeating step a-c for different predetermined beam powers, repeating step a-d for different positions on said work piece, wherein said beam spot size is verified if each detected settings of said focus lens and/or astigmatism lens are deviating less than a predetermined value from corresponding stored settings of said focus lens and/or astigmatism lens.