08-07-2015, 01:50 PM
i need the full material on night vision technology
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night vision technology full seminars report
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i need the full material on night vision technology
07-04-2017, 10:27 AM
Night vision is a technology that gives users a certain amount of vision in total darkness and improved vision in low-light environments. The most common applications include night driving or flight, night security and surveillance, wildlife observation, sleep laboratory monitoring and search and rescue. Night vision is often used by the military and also has recreational purposes, such as use in home video cameras or during night walking.
Night vision is a spy movie or action you've seen, in which someone ties up with a pair of night vision goggles to find another person in a dark building on a moonless night. With the right night vision equipment, you can see a person who is more than 200 yards (183 m) away on a moonless and cloudy night. Night vision can work in two very different ways, depending on the technology used.
"Image enhancement - This works by collecting the small amounts of light, including the lower portion of the infrared light spectrum, which are present, but may be imperceptible to our eyes, and amplification to the point that we can observe Easily picture.
"Thermal Imaging - This technology operates by capturing the upper part of the infrared light spectrum, which is emitted as heat by objects rather than simply reflected as light. Warm objects, such as hot bodies, emit more of this light than Objects colder like trees OR buildings.
To study about night vision technology we must first know about ligt.
The amount of energy in a light wave is related to its wavelength: shorter wavelengths have a higher energy. From visible light, violet has the most energy, and red has less. Just next to the spectrum of visible light is the infrared spectrum.
Night vision technology consists of two main types: light amplification (or intensification) and thermal (infrared) amplification.
Most consumer night vision products are light amplifier devices. All ITT Night Vision products use light amplification technology.
This technology takes the small amount of light in the surroundings (like moonlight or starlight), and converts the energy of light (scientists call it photons) into electrical energy (electrons).
These electrons pass through a thin disk that is approximately the size of a quarter and contains more than 10 million channels. As the electrons pass through the channels, they hit the walls of the channel and thousands more electrons are released. These multiplied electrons bounce off after a phosphor screen that converts electrons back into photons and allows you to see a stunning night view even when it's really dark.
In the night vision, the thermal image takes advantage of this infrared emission.
The thermal image works as
1. A special lens focuses on the infrared light emitted by all objects in sight.
2. The focused light is scanned by a phase array of infrared detector elements. The detector elements create a very detailed temperature pattern called a thermogram.
T only takes about a thirty second of a second for the array of detectors to get the temperature information to make the thermogram. This information is obtained from several thousand points in the field of view of the array of detectors.
3. The thermogram created by the detector elements is translated into electrical impulses.
4. The pulses are sent to a signal processing unit, a circuit board with a dedicated chip that translates the information of the elements into data for the display.
5. The signal processing unit sends the information to the screen, where it appears as several colours depending on the intensity of the infrared emission. The combination of all the impulses of all elements creates the image.
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