Aqua-Fi: Underwater WiFi developed using LEDs and lasers
Aquatic internet that sends data through light beams could enable divers to instantly transmit footage from under the sea to the surface.
Jun 11, 2020
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Aquatic internet that sends data through light beams could enable divers to instantly transmit footage from under the sea to the surface.
Jun 11, 2020
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Li-fi, a communication technology harnessing visible light for data transmission, has a potential to surpass Wi-Fi's speed by more than 100 times and boasts a high bandwidth, facilitating the simultaneous transmission of ...
Dec 29, 2023
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Like something out of a spy movie, thermal cameras make it possible to "see" heat by converting infrared radiation into an image. They can detect infrared light given off by animals, vehicles, electrical equipment and even ...
Jun 8, 2023
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Solar power has shown immense potential as a clean source of energy. Now, scientists in Korea have presented an innovative design for the development of a high-power transparent solar cell. This innovation is a step toward ...
Nov 3, 2020
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A nanomaterial made from phosphorus, known as phosphorene, is shaping up as a key ingredient for more sustainable and efficient next-generation perovskite solar cells (PSCs).
Jun 21, 2019
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One of the key aspects of academic and industrial research today is non-destructive imaging, a technique in which an object or sample is imaged (using light) without causing any damage to it. Often, such imaging techniques ...
May 21, 2021
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For generations, kids have been coaxed into finishing their vegetables after their parents sternly advised them that it is not nice to waste food when people are starving elsewhere in the world. But someday soon, kids may ...
Due to their advantageous properties, organic semiconductors could be very promising photocatalysts for producing solar fuels. In fact, these materials can be synthetically tuned to absorb visible light, while simultaneously ...
As climate change intensifies summer heat, demand is growing for technologies to cool buildings. Now, researchers report in ACS Energy Letters that they have used advanced computing technology and artificial intelligence ...
Nov 2, 2022
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Silicon photodiodes are semiconductor devices commonly used to detect visible light and measure its intensity, color and position. The fact that these devices are made of silicon has both advantages and disadvantages.
The visible spectrum is the portion of the electromagnetic spectrum that is visible to (can be detected by) the human eye. Electromagnetic radiation in this range of wavelengths is called visible light or simply light. A typical human eye will respond to wavelengths from about 380 to 750 nm. In terms of frequency, this corresponds to a band in the vicinity of 790–400 terahertz. A light-adapted eye generally has its maximum sensitivity at around 555 nm (540 THz), in the green region of the optical spectrum (see: luminosity function). The spectrum does not, however, contain all the colors that the human eyes and brain can distinguish. Unsaturated colors such as pink, and purple colors such as magenta are absent, for example, because they can only be made by a mix of multiple wavelengths.
Visible wavelengths also pass through the "optical window," the region of the electromagnetic spectrum that passes largely unattenuated through the Earth's atmosphere. (Blue light scatters more than red light, which is why the sky appears blue.) The human eye's response is defined by subjective testing (see CIE), but atmospheric windows are defined by physical measurement.
The "visible window" is so called because it overlaps the human visible response spectrum. The near infrared (NIR) windows lie just out of human response window, and the Medium Wavelength IR (MWIR) and Long Wavelength or Far Infrared (LWIR or FIR) are far beyond the human response region.
Many species can see wavelengths that fall outside the "visible spectrum". Bees and many other insects can see light in the ultraviolet, which helps them find nectar in flowers. Plant species that depend on insect pollination may owe reproductive success to their appearance in ultraviolet light, rather than how colorful they appear to us. Birds too can see into the ultraviolet (300-400 nm), and some have sex-dependent markings on their plumage, which are only visible in the ultraviolet range.
This text uses material from Wikipedia, licensed under CC BY-SA