‘And then the troops, unnoticed, surrounded whole of the desert city in that dark night, which certainly was all green for them’, we must have come across such lines in some or other war related article. Well, as quite a number of people do know that what does the word “green” here refers to, very few are able to tell the deep insights about it. This article takes every inch of that green and explains its cause, the night vision technology. Night vision technology, as the name suggests, is the expertise that makes us capable to see in the night without using any external light source such as a torch or a lamp. Highly advanced light sensitive cameras are used in this technology that produce clear visible images at night which the naked eye can’t do.
Wireless communication is among technology’s biggest contributions to mankind. Wireless communication involves the transmission of information over a distance without help of wires, cables or any other forms of electrical conductors. The transmitted distance can be anywhere between a few meters (for example, a television’s remote control) and thousands of kilometres (for example, radio communication). Some of the devices used for wireless communication are cordless telephones, mobiles, GPS units, wireless computer parts, and satellite television. The growth of wireless network has enabled us to use personal devices anywhere and anytime.
Infrared sensors find numerous applications in electronic systems. Commonly used as obstacle detector, their output is used in digital form (high & low logic) by [[wysiwyg_imageupload::]]employing a comparator. This topic explains a way to use the sensor’s output in its original analog form. Thus, along with detecting an obstacle, its exact distance can also be obtained. This is achieved by processing the output of IR sensor through an ADC0804 (analog to digital converter). The ADC is calibrated to get almost accurate distance measurement.The measured distance is also displayed on an LCD screen. The ADC0804 and LCD are interfaced with 8051 microcontroller (AT89C51) to perform these operations. The major drawback of IR based sensors is their capability of detecting short distances. Read more to find out how the circuit is assembled and coded. Also find out an interesting flash depicting the working of the sensor.