What is UV?
Source: | Author:weltool | Publish time: 2019-06-25 | 2941 Views | Share:
What is UV?

Ultraviolet, abbreviated as UV, is an electromagnetic wave with a wavelength between 100 nm and 400 nm. Electromagnetic waves do not need to rely on the medium to propagate, and their propagation speed is the speed of light in a vacuum. Electromagnetic waves can be classified by frequency, from low frequencies to high frequencies, including radio waves, microwaves, infrared rays, visible light, ultraviolet rays, X-rays, and gamma rays. The electromagnetic wave that the human eyes can receive, with a wavelength between about 380 and 780 nm, is called visible light. The following picture shows in detail the UV wavelengths of electromagnetic waves classified by frequency.

The UV light is divided into three ranges of A/B/C according to different wavelengths, namely UVA (315-400nm), UVB (280-315nm), and UVC (100-280nm) ultraviolet light. It can be seen that the ultraviolet light is not violet (generally considered to be purple at 380-420 nm), and is not blue (generally about 450 nm). Therefore, those flashlights with purple or blue light on the market are not the real UV flashlights, or in other words, the wavelengths of the light sources of these flashlights are relatively mixed and have a large amount of visible light wavelength.

The M2 uses a 365 nm wavelength UV-A LED, which is invisible. In general, electromagnetic waves of wavelengths between 380 and 780 nm are visible to the human eyes, ranging from red to violet, with wavelengths varying from high to low. When the wavelength is slightly lower than the visible purple color, it is ultraviolet (100-400 nm), and slightly higher than red is infrared.

M2 series have 3 models: M2-OL (Even-beam), M2-CF (Focused high radiation beam), and M2-BF (Focused pure beam).

Weltool M2 UV Series:  M2-OL Optical glass lens even-beam M2-CF Focused high radiation beam
M2-BF Focused pure beam
Tested with Weltool UB18-35 Rechargeable Lithium Battery Low radiant flux mode
High radiant flux mode Low radiant flux mode High radiant flux mode Low radiant flux mode High radiant flux mode
LED Radiant flux
680mW 2060mW 680mW 2060mW 680mW 2060mW
Spectral radiosity @38cm (15in) (μW/cm2 350 1100 3940 11600 2900 10500
Irradiated area (round) diameter of distance @38cm(15in) 36cm 38cm 38cm
Central beam (round) diameter of distance @ 38cm(15in) 36cm 6cm 6cm
Visible spectrum illuminance distance @ 38cm(15in) ≤ 6Lux ≤  19Lux ≤ 72Lux ≤  179Lux ≤ 11Lux ≤ 31Lux
Runtime(h): Until radiosity falls to 10%  10h25min 4h20min 10h25min 4h20min 10h25min 4h20min
Dimensions: (Bezel Dia.) x (Body Dia.) x (Length) 27.5mm*23mm*123mm 27.5mm *23mm*135mm 27.5mm *23mm*135mm
Weight ±0.5 (w/o battery)
80.5g 80.5g