I don't see 4 lasers on my drive. I found just one laser till from my purchase. It's quite interesting. Really i don't know about them.What do you mean, you don't SEE any lasers? Did you take the drive apart??I'm RUNNING my notebook with ac power ( very poor battery backup). In the beginning all the peripherals all at low temperature even my DVD drive but at later times it's (temperature) going to increase beyond the CERTAINS limits over 80C. I think this may be the problem, isn't it ?

Can you provide me more information regarding how to decrease this temperature of my drive. And one more ISSUE is that "how to clean my drive ?"What drive are you talking about?

What temperatures?

How are you reading these temperatures?I'm talking about Acer aspire 4720 DVD RW Drive.
I read the temperatures by using http://www.almico.com/installspeedfan439.exe software.
The temperatures of my peripherals are increasing gradually upto 80C-83C(processor) and 52c(harddisk) . At the beginning they were low.It's only natural that computers (especially laptops) get hot when they're powered on.

The best you could do is avoid running high-intensity / demanding programs or games for prolonged periods of time, keep the VENTS clear and unobstructed, and keeping the temperature of the room down.