Use of UV Lamp in screen replacement

[Dev Miner]

Hello, I watched a lot of videos on how to replace screen for android.

So, I've been wondering why do we have to use UV Lamp after we stick the digitizer and the LCD together?
Is it necessary to do that? If it is, can we use sunlight as an alternative method if we don't have the UV Lamp?

 

[Dev Miner]

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