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44-456: Mark XIX or Mark 19 may refer to: Military [ edit ] Mk 19 grenade launcher , a widely used American belt-fed weapon that fires 40 mm grenades Mark 19 torpedo , a prototype American torpedo Desert Eagle or Mark XIX (1982), a U.S.-Israeli large caliber semi-automatic pistol Logistics Vehicle System MK19 Rear Body Unit ; US Marine Corps heavy tactical vehicle trailer incorporating

88-538: A tapetum lucidum , tissue behind the retina that reflects light back through the retina thus increasing the light available to the photoreceptors. Night-useful spectral range techniques can sense radiation that is invisible to a human observer. Human vision is confined to a small portion of the electromagnetic spectrum called visible light . Enhanced spectral range allows the viewer to take advantage of non-visible sources of electromagnetic radiation (such as near- infrared or ultraviolet radiation). Some animals such as

132-479: A crane United Kingdom [ edit ] BL 6-inch gun Mk XIX (1916–1940), an artillery piece made by Vickers CP Mk.XIX, a Royal Navy central-pivot twin-mount carrying two quick-firing 4-inch guns HA/LA Mk.XIX, a Royal Navy high-angle/low-angle twin-mount carrying two quick-firing 4-inch guns De Havilland Mosquito NF Mk XIX, a night fighter variant De Havilland Mosquito that could mount American or British radar Supermarine Spitfire Mk 19 (1944),

176-462: A dual-color variant of the ANVIS for use in the cockpit of airborne platforms. Active illumination couples imaging intensification technology with an active source of illumination in the near infrared (NIR) or shortwave infrared (SWIR) band. Examples of such technologies include low light cameras. Active infrared night-vision combines infrared illumination of spectral range 700–1,000 nm (just over

220-588: A large variety of naval mounts. The Mk 19 automatic grenade launcher replaced the earlier Mk 18 hand-cranked multiple grenade launcher. The 40 mm ammunition used (40×53 mm) is not interchangeable with that used in the M203 (40×46 mm). The M203 ammunition develops a lower chamber pressure, and resultant lower muzzle velocity and range, compared to ammunition loaded for the Mk ;19. The Mk 19 fires from an open bolt . The rounds are mechanically fed onto

264-411: A larger optical aperture (the pupils may expand to the physical limit of the eyelids), more rods than cones (or rods exclusively) in the retina , and a tapetum lucidum . Enhanced intensity range is achieved via technological means through the use of an image intensifier , gain multiplication CCD , or other very low-noise and high-sensitivity arrays of photodetectors . All photoreceptor cells in

308-432: A rigid casing, commonly used by military forces . Lately, night vision technology has become more widely available for civilian use. For example, enhanced vision systems (EVS) have become available for aircraft, to augment the situational awareness of pilots to prevent accidents. These systems are included in the latest avionics packages from manufacturers such as Cirrus and Cessna . The US Navy has begun procurement of

352-445: A source of illumination. They produce an image in the darkest of nights and can see through light fog, rain, and smoke (to a certain extent). Thermal imaging cameras make small temperature differences visible. They are widely used to complement new or existing security networks, and for night vision on aircraft, where they are commonly referred to as "FLIR" (for "forward-looking infrared"). When coupled with additional cameras (for example,

396-563: A subsidiary of Singapore Technologies Kinetics , to manufacture 40 mm high-velocity airburst ammunition for the U.S. military. The 40 mm airburst grenade uses a programmable, time-based fuse that computes and programs the detonation time into it, which counts down once fired to zero to detonate at the intended target point. The airburst ammunition is compatible with the Mk 19, which would give it greater effectiveness and lethality, particularly against concealed and defilade targets. The Mk 19

440-647: A variant integrated into a helmet-mounted display, produced by Elbit Systems. A specific type of NVD, the night vision goggle (NVG) is a night vision device with dual eyepieces. The device can utilize either one intensifier tube with the same image sent to both eyes, or a separate image intensifier tube for each eye. Night vision goggles combined with magnification lenses constitutes night vision binoculars. Other types include monocular night vision devices with only one eyepiece which may be mounted to firearms as night sights. NVG and EVS technologies are becoming more popular with helicopter operations, to improve safety. The NTSB

484-427: A visible spectrum camera or SWIR) multispectral sensors are possible, which take advantage of the benefits of each detection band's capabilities. Contrary to misconceptions portrayed in the media, thermal imagers cannot "see" through solid objects (walls, for example), nor can they see through glass or acrylic, as both these materials have their own thermal signature and are opaque to long wave infrared radiation. Before

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528-423: Is a belt-fed, blowback-operated, air-cooled, crew-served, fully-automatic weapon that is designed not to cook off . It fires 40 mm grenades at a cyclic rate of 325 to 375 rounds per minute, giving a practical rate of fire of 60 rounds per minute (rapid) and 40 rounds per minute (sustained). The weapon operates on the blowback principle, which uses the chamber pressure from each fired round to load and re-cock

572-611: Is a biological process that contributes a relatively minor amount to night vision. In humans, the irises can adjust the size of the pupil from 2 mm in bright light, to as large as 8 mm in dark conditions, but this varies by individual and age, with age causing the maximal pupil diameter to decrease. However, some humans are capable of dilating their pupils to over 9 mm in diameter in the dark, giving them better night vision capabilities. Night vision technologies can be broadly divided into three main categories: image intensification , active illumination , and thermal imaging . This magnifies

616-462: Is a technique which controls the laser pulses in conjunction with the shutter speed of the camera's detectors. Gated imaging technology can be divided into single shot , where the detector captures the image from a single light pulse, and multi-shot , where the detector integrates the light pulses from multiple shots to form an image. One of the key advantages of this technique is the ability to perform target recognition rather than mere detection, as

660-425: Is considering EVS as recommended equipment for safety features. Night glasses are single or binocular with a large diameter objective. Large lenses can gather and concentrate light, thus intensifying light with purely optical means and enabling the user to see better in the dark than with the naked eye alone. Often night glasses also have a fairly large exit pupil of 7 mm or more to let all gathered light into

704-478: Is especially effective when used against enemy infantry formations. The ammunition comes in cans that hold a 32- or 48-grenade belt weighing 42 and 60 pounds (19 and 27 kg), respectively. Due to its low recoil and comparatively light weight, it has been adapted for use on many different platforms, including small attack boats, fast attack vehicles such as the Humvee (HMMWV), AAV and Stryker , military jeeps, and

748-475: Is now commonly found in commercial, residential and government security applications, where it enables effective night time imaging under low-light conditions. However, since active infrared light can be detected by night-vision goggles, there can be a risk of giving away position in tactical military operations. Laser range gated imaging is another form of active night vision which utilizes a high powered pulsed light source for illumination and imaging. Range gating

792-456: Is the case with thermal imaging. Thermal imaging detects the temperature difference between background and foreground objects. Some organisms are able to sense a crude thermal image by means of special organs that function as bolometers . This allows thermal infrared sensing in snakes , which functions by detecting thermal radiation. Thermal imaging cameras are excellent tools for night vision. They detect thermal radiation and do not need

836-407: Is the high-explosive dual-purpose M430 grenade. On impact, the grenade can kill anyone within a radius of five metres (16 ft), and wound them within a radius of 15 metres (49 ft). It can also penetrate two inches (5.1 cm) of rolled homogeneous armor with a direct hit (0-degree obliquity), which means it can penetrate most infantry fighting vehicles and armored personnel carriers . It

880-628: Is used as part of the Şahin counter unmanned air system (C-UAS) developed by Aselsan , which entered service with the Turkish Armed Forces in July 2022 and uses Atom 40 mm ammunition to detect and destroy mini and micro UAVs out to 700 meters. "Although the MK 19 is a recent entry into the Army’s inventory, development began in 1963. The first version was a hand-cranked, multiple grenade launcher called

924-402: The mantis shrimp and trout can see using much more of the infrared and/or ultraviolet spectrum than humans. Sufficient intensity range is simply the ability to see with very small quantities of light. Many animals have better night vision than humans do, the result of one or more differences in the morphology and anatomy of their eyes. These include having a larger eyeball, a larger lens,

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968-451: The visible spectrum of the human eye) with CCD cameras sensitive to this light. The resulting scene, which is apparently dark to a human observer, appears as a monochrome image on a normal display device. Because active infrared night-vision systems can incorporate illuminators that produce high levels of infrared light, the resulting images are typically higher resolution than other night-vision technologies. Active infrared night vision

1012-456: The MK 18. In 1966 the need for more firepower inspired the development of a self-powered 40-mm machine gun called the MK 19, MOD 0. This model was neither reliable nor safe enough for use as a military weapon system. Product improvements begun in 1971 resulted in the 1972 MOD 1, of which only six were produced. The MOD 1 performed effectively in Navy riverine patrol craft and broader applications for

1056-621: The MK 19 were found. In 1973 the Navy developed the MOD 2, which featured improved reliability, safety, and maintainability. In 1976 a complete redesign resulted in the MK 19, MOD 3, which the Army adopted in 1983. The Army now uses the MK 19 within the tactical environment for defense, retrograde, patrolling, rear area security, urban operations, and special operations." - Department of the Army. November 2003 - GDOTS has built nearly 35,000 Mk 19 Mod 3 systems for roughly 30 customers since 1984. Users of

1100-414: The Mk 19 include: Night vision Night vision is the ability to see in low-light conditions, either naturally with scotopic vision or through a night-vision device . Night vision requires both sufficient spectral range and sufficient intensity range . Humans have poor night vision compared to many animals such as cats , dogs , foxes and rabbits , in part because the human eye lacks

1144-534: The PVS-31 binocular and GPNVG-18 quad-tube night vision are used by special forces groups, but are costly. Monoculars are generally preferred by developed forces. Night vision systems can also be installed in vehicles. An automotive night vision system is used to improve a vehicle driver's perception and seeing distance in darkness or poor weather. Such systems typically use infrared cameras, sometimes combined with active illumination techniques, to collect information that

1188-416: The amount of received photons from various natural sources such as starlight or moonlight. Examples of such technologies include night glasses and low light cameras. In the military context, Image Intensifiers are often called "Low Light TV" since the video signal is often transmitted to a display within a control center. These are usually integrated into a sensor containing both visible and IR detectors and

1232-581: The back of the eye that reflects light back through the retina , increasing the amount of light available for it to capture, but reducing the sharpness of the focus of the image. This is found in many nocturnal animals and some deep sea animals, and is the cause of eyeshine. Humans, and monkeys, lack a tapetum lucidum . Nocturnal mammals have rods with unique properties that make enhanced night vision possible. The nuclear pattern of their rods changes shortly after birth to become inverted. In contrast to conventional rods, inverted rods have heterochromatin in

1276-500: The bolt face with the pull of the charging handles. When the trigger is pressed, the bolt closes, and the firing pin is released. The recoil blows back the bolt, feeds a new round onto the bolt face, which pushes the expended casing off the bolt face. Production of the Mk 19 is managed by Saco Defense Industries (now a division of General Dynamics Ordnance and Tactical Systems ). In November 2014, General Dynamics entered into an agreement with Advanced Material Engineering Pte Ltd,

1320-472: The center of their nuclei and euchromatin and other transcription factors along the border. In addition, the outer layer of cells in the retina (the outer nuclear layer ) in nocturnal mammals is thick due to the millions of rods present to process the lower light intensities. The anatomy of this layer in nocturnal mammals is such that the rod nuclei, from individual cells, are physically stacked such that light will pass through eight to ten nuclei before reaching

1364-469: The emitting. The image is said to become "intensified" because the output visible light is brighter than the incoming light, and this effect directly relates to the difference in passive and active night vision goggles . Currently, the most popular image intensifier is the drop-in ANVIS module, though many other models and sizes are available at the market. Recently, the US Navy announced intentions to procure

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1408-428: The eyesight of its operator, not concealing the weapon's position. For night operation, a picatinny rail quadrant sight can be added for thermal and night vision optics. The Mk 19A is a man-portable crew-served weapon that can fire from a tripod-mounted position or from a vehicle mount, with the latter being the preferred method, as the weapon alone weighs 77.6 pounds (35.2 kg). The primary ammunition for it

1452-413: The introduction of image intensifiers, night glasses were the only method of night vision, and thus were widely utilized, especially at sea. Second World War era night glasses usually had a lens diameter of 56 mm or more with magnification of seven or eight. Major drawbacks of night glasses are their large size and weight. A night vision device (NVD) is a device comprising an image intensifier tube in

1496-555: The last and most successful Supermarine Spitfire photographic reconnaissance variant Vickers Wellington T Mk XIX, service conversion of the Vickers Wellington Mk X for use as a navigation trainer ASV Mk. 19 (anti surface vessel), an EKCO airborne radar fitted to the Royal Navy Fairey Gannet Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with

1540-416: The light is "amplified," it is not. When light strikes a charged photocathode plate, electrons are emitted through a vacuum tube and strike the microchannel plate. This causes the image screen to illuminate with a picture in the same pattern as the light that strikes the photocathode and on a wavelength the human eye can see. This is much like a CRT television , but instead of color guns the photocathode does

1584-411: The night vision adaptation occurs within the first five minutes in the dark. Adaptation results in maximum sensitivity to light. In dark conditions only the rod cells have enough sensitivity to respond and to trigger vision. Rhodopsin in the human rods is insensitive to the longer red wavelengths , so traditionally many people use red light to help preserve night vision. Red light only slowly depletes

1628-436: The photoreceptor portion of the cells. Rather than being scattered, the light is passed to each nucleus individually, by a strong lensing effect due to the nuclear inversion, passing out of the stack of nuclei, and into the stack of ten photorecepting outer segments . The net effect of this anatomical change is to multiply the light sensitivity of the retina by a factor of eight to ten with no loss of focus. Pupillary dilation

1672-409: The physiological process which results in vision. The retinal must diffuse from the vision cell, out of the eye, and circulate via the blood to the liver where it is regenerated. In bright light conditions, most of the retinal is not in the photoreceptors, but is outside of the eye. It takes about 45 minutes of dark for all of the photoreceptor proteins to be recharged with active retinal, but most of

1716-415: The rhodopsin stores in the rods, and instead is viewed by the red sensitive cone cells . Another theory posits that since stars typically emit light with shorter wavelengths, the light from stars will be in the blue-green color spectrum. Therefore, using red light to navigate would not desensitize the receptors used to detect star light. Many animals have a tissue layer called the tapetum lucidum in

1760-430: The streams are used independently or in fused mode, depending on the mission at hand's requirements. The image intensifier is a vacuum-tube based device (photomultiplier tube) that can generate an image from a very small number of photons (such as the light from stars in the sky) so that a dimly lit scene can be viewed in real-time by the naked eye via visual output, or stored as data for later analysis. While many believe

1804-472: The title Mark XIX . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Mark_XIX&oldid=1242316747 " Category : Disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages Mk 19 grenade launcher The Mk 19

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1848-577: The user's eye. However, many people cannot take advantage of this because of the limited dilation of the human pupil . To overcome this, soldiers were sometimes issued atropine eye drops to dilate pupils. Currently, the PVS-14 monocular is the most widely used and preferred night vision device across NATO forces. It is used by the United States army, and is known for its low cost and wide range of uses and modification ability. Some higher end devices including

1892-419: The vertebrate eye contain molecules of photoreceptor protein which is a combination of the protein photopsin in color vision cells , rhodopsin in night vision cells , and retinal (a small photoreceptor molecule). Retinal undergoes an irreversible change in shape when it absorbs light; this change causes an alteration in the shape of the protein which surrounds the retinal, and that alteration then induces

1936-418: The weapon. The Mk 19 can launch its grenade at a maximum distance of 2,212 meters (2,419 yd), though its effective range to a point target is about 1,500 meters (1,600 yd), since the large rear leaf sight is only graduated as far. The nearest safe distance to launch the grenade is 310 meters in training and 75 meters in combat. Though the Mk 19 has a flash suppressor , it serves only to save

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