thethinkingatom

Ultraviolet(UV) light and Infrared light(IR) are two forms of invisible electromagnetic radiation which are on opposite ends of the visible light spectrum. UV light has high energy and a shorter wave length making it suitable for sterilization (the process of removing all forms of microbial life) and IR light which has a longer wavelength and less energy, making it suitable for making sensors, remotes and thermal applications.

Ultraviolet(UV) light:

This form of radiation has a wavelength of 10-400nm(nanometer: one-billionth of a meter (1 × 10⁻⁹ m)). It has high energy (capable of damaging DNA and causing sunburns). UV light has 3 categories:

UVA (320–400 nm): Reaches Earth; used in tanning beds, blacklights (specialized lamps that emit long-wave ultraviolet (UV-A) radiation alongside a faint violet glow), detecting counterfeit money and forensic traces.
UVB (280–320 nm): Partially blocked by the atmosphere; creates Vitamin D.
UVC (100–280 nm): Blocked by the atmosphere; used for UVC sterilization. It is also used for purposes like water and air purification.

While all of these tasks utilize the broader ultraviolet spectrum, they require completely different wavelengths.

Infrared(IR) light:

The wavelength of IR radiation is 700 nm/ 0.7 micrometers to 1000 micrometers. It has low energy. It has 2 categories:

Near-IR (NIR): Used in electronic remotes and fiber optics.
Far-IR (FIR): Associated with thermal radiation and heat.

It’s common uses are thermal imaging and night-vision goggles,
IR saunas and space heaters and TV remotes, optical sensors, and data transmission.

While they serve very different purposes, both UV and IR are heavily utilized together in specialized sectors, such as indoor plant cultivation. Supplemental UV is known to stimulate pest-resistance in plants, while supplemental IR promotes stem growth and flowering transitions.

Left(UV), Middle(Visible light) and right(IR)- Wavelength is written below in nanometers

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