light gun this article is about the computer peripheral for the artillery piece see l118 light gun for analogue light signal used in air traffic control see aviation light signals for laser weapons see directedenergy weapon not to be confused with small arms the nes zapper nintendos early light gun the light phaser for the sega master system the atari inc xg1 light gun a light gun is a pointing device for computers and a control device for arcade and video games typically shaped to resemble a pistol in aviation and shipping it can also be a directional signal lamp modern screenbased light guns work by building an optical sensor into the gun which receives its input from the light emitted by onscreen targets the first device of this type the light pen was used on the mit whirlwind computer the light gun and its ancestor the light pen are now rarely used as pointing devices due largely to the popularity of the mouse and changes in monitor display technologyconventional light guns work only with crt monitors early history light gun shooter the first light guns appeared in the 1930s following the development of lightsensing vacuum tubes it was not long before the technology began appearing in arcade shooting games beginning with the seeburg rayolite in 1936 these early light gun games like modern laser tag used small targets usually moving onto which a lightsensing tube was mounted the player used a gun usually a rifle that emitted a beam of light when the trigger was pulled if the beam struck the target a hit was scored these games evolved throughout subsequent decades culminating in segas periscope the companys first successful game released in 1966 which required the player to target cardboard ships use in video games the video game light gun is typically modeled on a ballistic weapon usually a pistol and is used for targeting objects on a video screen with force feedback the light gun can also simulate the recoil of the weapon the first gun for a home console was in fact a big rifle the magnavox odysseys shooting gallery which looked very lifelike and even needed to be cocked after each shot light guns are very popular in arcade games but had not caught on as well in the home video game console market until after the nintendo entertainment system nes sega master system sms mega drivegenesis super nintendo entertainment system snes systems and atari xegs many home pong systems of the 1970s included a pistol or gun for shooting simple targets on screen nintendos nes zapper for the nes is the most popular example of the light gun and duck hunt its most popular game traditional light guns cannot be used on the newer lcd and plasma screens and have problems with projection screens there are also light guns for sega saturn playstation and several other console and arcade systems recent light gun video games include resident evil the umbrella chronicles time crisis 4 virtua cop 3 and the house of the dead overkill in 2007 nintendo released the wii zapper for the wii a peripheral which is actually a plastic shell that houses both the wii remote and nunchuk for gunstyle video games while it does not contain any traditional light gun technology the peripheral makes use of the wii remotes builtin infrared tracking system to shoot targets that correspond onscreen its name is a reference to the classic nes zapper for the nintendo entertainment system sony have also released attachments that house the playstation move motion controller in the form of a pistol and rifle the latter named the sharp shooter namcos guncon 3 also uses an infrared optical sensor system similar to the wii remote design the light gun is named because it uses light as its method of detecting where on screen the user is targeting the name leads one to believe that the gun itself emits a beam of light but in fact most light guns actually receive light through a photodiode in the gun barrel there are two versions of this technique that are commonly used but the concept is the same when the trigger of the gun is pulled the screen is blanked out to black and the diode begins reception all or part of the screen is painted white in a way that allows the computer to judge where the gun is pointing based on when the diode detects light the user of the light gun notices little or nothing because the period in which the screen is blank is usually only a fraction of a second see persistence of vision sequential targets the first detection method used by the zapper involves drawing each target sequentially in white light after the screen blacks out the computer knows that if the diode detects light as it is drawing a square or after the screen refreshes then that is the target at which the gun is pointed essentially the diode tells the computer whether or not the player hit something and for n objects the sequence of the drawing of the targets tell the computer which target the player hit after 1 ceillog2n refreshes one refresh to determine if any target at all was hit and ceillog2n to do a binary search for the object that was hit a side effect of this is that on poorly designed games often a player can point the gun at a light bulb or other bright light source pull the trigger and cause the system to falsely detect a hit on the first target every time better games account for this either by detecting if all targets appear to match or by displaying a black screen and verifying that no targets match cathode ray timing the black guncon made by namco for the playstation the blue top and pink middle konami justifiers made for the super nintendo entertainment system and the green bottom one made for the playstation the second method used by the super nintendo entertainment systems super scope and computer light pens is more elaborate and more accurate the trick to this method lies in the nature of the cathode ray tube inside the video monitor crts were the only affordable tv monitors in the late 1980s and early 1990s when this method was popularized the screen is drawn by a scanning electron beam that travels across the screen starting at the top until it hits the end and then moves down to update the next line this is done repeatedly until the entire screen is drawn and appears instantaneous to the human eye as it is done very quickly when the player pulls the trigger the computer often assisted by the display circuitry times how long it takes the electron beam to excite the phosphor at the location at which the gun is pointed the light gun sends a signal after sensing the sudden small change in brightness of a point on the screen when the electron gun refreshes that spot the computer then calculates the targeted position based on the monitors horizontal refresh rate the fixed amount of time it takes the beam to get from the left to right side of the screen either the computer provides a time base for the horizontal refresh rate through the controllers connector as in the super scope or the gun reads the composite video signal through a tconnector on the av cable as in the guncon 2 once the computer knows where the gun is pointed it can tell through collision detection if it coincides with the target or not many guns of this type including the super scope ignore red light as red phosphors have a much slower rate of decay than green or blue phosphors as a result some but not all games brighten the entire screens greenblue pixels somewhat when the trigger is pulled in order to get a more reliable fix on the position display timing is not possible with plasma lcd and dlp monitors since they do not have an off state between refreshes their digital signal processing electronics also may introduce a nontrivial lag between the signal input and display output which is not predictable because it varies between monitor models and brands and even between mode settings of a single monitor a lag which is not very significant for player feedback may be enough to completely destroy the accuracy of a displaytiming based light gun system infrared emitters a new method was developed to compensate for display technologies other than crt it relies on one or several infrared light emitters placed near the screen and one ir sensor on the muzzle of the gun when the trigger is pressed the gun sends the intensity of the ir beam it detects since this intensity depends upon both distance and relative angle to the screen angle sensors are located in the gun this way a trigonometric equation system is solved and the muzzles 3d position relative to the screen is calculated then by projecting the muzzle on the screen with the measured angles the impact point is determined an early example of this technology though not using ir can be seen in the nes power glove accessory which used three ultrasonic sensors serving the same function as the ir emitters used in some lightguns a simpler variant is commonly used in arcades where there are no angle detectors but 4 ir sensors however this can prove inaccurate when shooting from certain distances and angles since the calculation of angles and 3d position has a larger margin of error other variants include 3 or more emitters with different infrared wavelengths and the same number of sensors with this method and proper calibration three or more relative angles are obtained thus not needing angle detectors to position the gun sometimes the sensors are placed around the screen and the emitter on the gun but calculations are similar the wii remote uses an infrared video camera in the handheld controller rather than a simple sensor this family of methods are used for the wii remote guncon 3 and modern arcade light gun games the downside of this method is that its not as accurate as a traditional light gun the additional ir image processing results in lag or cursor drift ie when quickly sweeping the light gun across the screen the crosshair will seem to drag slightly behind where the light gun is actually pointing image capture when the user pulls the trigger the screen is replaced for a splitsecond with a seemingly random display of black and white pixels or groups of pixels blocks the light gun contains a fineresolution but low pixel count digital camera with a very narrow field of view with just a handful of the dot image pixels captured the gun converts the small image into a binary array which allows the computer to locate the exact position the gun was pointed at this method is compatible with any screen of any size the size of the screen and distance to shooter is entered into the gun driver software to determine the dimensions of the random blockspixels to best allow rendering on the light gun ccd multiplayer a game that uses more than one gun reads both triggers continuously and then when one player pulls a guns trigger the game reads that gun until it knows which object was hit positional guns positional guns are fairly common in video arcades a positional gun is a gun mounted to the cabinet on a swivel that allows the player to aim the gun these are often confused with light guns but work quite differently these guns may not be removed from the cabinet like their optical counterparts which are tethered and stored in a mounted holster they are typically more expensive initially but easier to maintain and repair games that use positional guns include silent scope and terminator 2 judgment day console ports sometimes use light guns a positional gun is essentially an analog joystick that records the position of the gun to determine where the player is aiming on the screen some games however have mounted optical guns such as exidys crossbow light gun models oscilloscope light gun braun 1947 beam gun nintendo 1970 shooting gallery magnavox odyssey 1972 laser clay shooting system nintendo 1973 wild gunman nintendo 1974 wonder wizard general home products 1976 colorsport viii granada 1976 gd1380 heathkit 1976 tvsports 801 lloyds 1976 sportsman tournament 150 200 2000 2501 unisonic 1976197619771977 telstar ranger telstar arcade telstar marksman coleco 197719771978 tv fun sportsrama apf electronics 1977 tv master 6 binatone 1977 visio matic 101 cit alcatel 1977 model 1199 interstate company 1977 markint 6 markint 1977 n20 light gun philips 1977 visiomat 11 pizonbross 1977 tv scoreboard radioshack 1977 home tv game santron 1977 tv game sennheiser 1977 105 sportron 1977 501 starex 1977 mark vc unimex 1977 xk 600b ingersoll company 1978 jeu tv tvg6 klevox 1978 oc 5000 occitane soe 1978 videosport prinztronic 1978 color tv game sands 1978 telescore seb company 1978 sports centre colour tv game 3600 mk iii granada company 1979 color multispiel universum 1979 nes zapper nintendo 1984 light phaser sega 1986 magnum light phaser zx spectrum 1987 xg1 atari xegs 1987 action max worlds of wonder 1987 plusx terminator laser ascii 1989 laserscope konami 1990 super scope nintendo 1992 menacer sega 1994 gamegun 3do interactive multiplayer peacekeeper revolver philips cdi 1994 guncon namco 1997 sega saturn stunner 1995 dreamcast light guns sega 20002003 guncon 2 namco 2001 topgun ems 2005 topgun ii ems 2007 wii zapper nintendo 2007 guncon 3 namco 2008 nerf nstrike nerf 2008 integrated pistol moprousa 2008 psvr aim controller sony computer entertainment 2017 light gun shooter list of light gun games vtevideo game controllerscontroller types arcade controller balance board digital camera dance pad fishing rod gamepad gaming keypad interactive urinal joystick keyboard light gun microphone motion controller mouse musical instruments nunchaku paddle racing wheel remote control throttle quadrant virtual reality headset wired glove controller partsphysical buttons analog stick arrow keys circle pad dpad discpad face button scroll wheel select button shoulder button start button telephone keypad trigger turbo button sensitive accelerometer haptic technology stylus pen touchpad touchscreen trackball related multitap rob 