How infrared thermometer/ thermal scanner works?

How infrared thermometer/ thermal scanner works?

Now a days CORONA virus is increasing so it emits lots of radiation and it increases temperature and for checking every where lots of thermal scanner is used.
so lets check the How its work

For understanding  Infrared thermometer first need to understand about the LASER its full form is as under

L = Light

A = Amplification of

S = Simulated

E = Emission of

R = Radiation

 As comparing to normal torch it provides continuous same color and concentrate on one point its not fade over the path there are some reason for having laser properties below:

• it is wavelength is monochromatic:depends on the color of the light produced by that monochromatic source 
• it is coherent :two wave sources are perfectly coherent if they have a constant phase difference and the same frequency

How infrared thermometer/ thermal scanner works?

Here is attached  figure which clarifies the difference between wavelength

infrared thermometer/ thermal scanner : it uses the LASER to check the temperature in Celsius 

this scanner not check the inner temperature of body it just check the skin temperature

How infrared thermometer/ thermal scanner works?

any material in world which heated it emits the radiation 

it is the radiation which emits from sun 

there are three types of the light emits from sun is

1. Ultraviolet light
2. Invisible light
3. Infrared light

If you want to measure the temperature of body than you need to measure about the wave lenth emits from the material
any body temperature = infrared wave length 

there is diagram shows below:

as shown in figure Thermometer works ray apply to body / material which emits energy than replied ray is different from ray applied than difference is measured and display on the screen

it specification and what it indicates:

distance to spot ration - 12:1  (Distance in ft :diameter of spot in ft)

it very important to check the distance to spot ratio if distance is more than you will not get the perfect temperature

The LASER  in the thermal scanners is just to point out that you are measuring the the part 

How infrared thermometer/ thermal scanner works?