Biological night vision[edit] For more details on this topic, see Adaptation (eye). "Night sight can mean life or death. Eat carrots and leafy greens or yellow vegetables, rich in vitamins," WWII poster In biological night vision, molecules of rhodopsin in the rods of the eye undergo a change in shape as they absorb light. Rhodopsin is the chemical that allows night-vision, and is extremely sensitive to light. Exposed to a spectrum of light, the pigment immediately bleaches, and it takes about 30 minutes to regenerate fully, but most of the adaptation occurs within the first five or ten minutes in the dark. Rhodopsin in the human rods is less sensitive to the longer red wavelengths of light, so traditionally many people use red light to help preserve night vision as it only slowly depletes the eye's rhodopsin stores in the rods and instead is viewed by the cones. However the US submarine force ceased using red lighting for night adaptation after studies found little significant advantage of using low level red over low level white lighting.[3] [4] Many animals have a tissue layer called the tapetum lucidum in the back of the eye that reflects light back through the retina, increasing the amount of light available for it to capture. This is found in many nocturnal animals and some deep sea animals, and is the cause of eyeshine. Humans 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 contemporary rods, inverted rods have heterochromatin in the center of their nuclei and euchromatin and other transcription factors along the border. In addition, the outer nuclear layer (ONL) in nocturnal mammals is thick due to the millions of rods present to process the lower light intensities of a few photons. Rather than being scattered, the light is passed to each nucleus individually.[5] In fact, an animal's ability to see in low light levels may be similar to what humans see when using first- or perhaps second-generation image intensifiers.[citation needed] Night vision technologies[edit] 1974 US army film about the development of military night vision technology Night vision technologies can be broadly divided into three main categories: image intensification, active illumination and thermal imaging. Image intensification[edit] Main article: Image intensifier This magnifies 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. The image intensifier is a vacuum-tube based device that converts invisible light from an image to visible light so that a dimly lit scene can be viewed by a camera or the naked eye. While many believe the light is "amplified," it is not. When light strikes a charged photocathode plate, electrons are emitted through a vacuum tube that strike the microchannel plate that cause the image screen to illuminate with a picture in the same pattern as the light that strikes the photocathode, and is on a frequency that the human eye can see. This is much like a CRT television, but instead of color guns the photocathode does the emitting. The image is said to become "intensified" because the output visible light is brighter than the incoming IR 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. Active illumination[edit] Imaging results with (top) and without (bottom) active-infrared. 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 below 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.[6] 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.[7][8] Active infrared night vision 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 is a technique which controls the laser pulses in conjunction with the shutter speed of the camera's detectors.[9] 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 is the case with thermal imaging.
Snooperscope
From Wikipedia, the free encyclopedia
| 300px
Night Vision Device for smartphone
| |
| Also known as | Snooperscope Night Vision Device |
|---|---|
| Developer | Marco Montresor Eros Luca Parise |
| Type | Night Vision Device for smartphone |
| Release date | June, 2014 (expected) |
| Website | snooperscope.co.uk |
Snooperscope is a portable Night Vision device that can be used with a smartphoneor tablet and used as an extra camera to see in completely darkness.
A Kickstarter campaign was launched in November 2013 to raise funds for Snooperscope. The campaign ended on December 25 with a total of £79,686 pledged. The devices are expected to be shipped out by June 2014.
Background[edit]
Funding[edit]
The Kickstarter campaign of Snooperscope was launched on November 25, 2013 with a stated goal of securing a funding of £40,000 in 30 days. After being featured on multiple blogs and media outlets, the Kickstarter campaign went viral. Snooperscope surpassed the £40,000 goal in 12 days and acquired less than two-times of its goal in 30 days. The campaign closed on December 25 with a total of £79,686 pledged from 1,556 backers. The devices are expected to be delivered to the backers by June 2014.
For a £26 pledge, donors were offered the device and the application, with a choice of colors.
Development[edit]
Snooperscope was developed by Marco Montresor and Eros Luca Parise, italians. According to Marco, he came up with the idea of Snooperscope after having developed several applications with some camera devices for smartphones in 2013 and "noticing that my awesome devices are lacking the most intuitive input camera sensor for night vision." Marco then quit his day job of an application developer, teamed up with his friend Eros, and started working on the development of the Snooperscope. During the development of the device, the team grew to include a usability experience specialist, and a web developer.
By late 2013, the team had many working prototypes and models of the Snooperscope, all of which were made using 3D printing.
Device[edit]
Snooperscope can be used with smartphones and tablets. The application works by running on Android and iOS as a display service.
Snooperscope is available in four colors - black, white, hunter, and camouflage.
In the media[edit]
When the Kickstarter campaign of Snooperscope was launched in November 2013, it was featured in multiple publications and technology blogs.
External links[edit]
See also[edit]
Patents[edit]
- US D248860 - Night vision Pocketscope
- US 4707595 - Invisible light beam projector and night vision system
- US 4991183 - Target illuminators and systems employing same
- US 6075644 - Panoramic night vision goggles
- U.S. Patent 7,173,237
- US 6158879 - Infra-red reflector and illumination system
another good link
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