well Im using the batteries it says but its working like a 5mW :S Its original selling prize is 30$ is that normal _?
and will there any change if I use litium batteries_?
If it was actually 100mW then $30 is a good deal. I believe some people have said that Lithium can produce slightly too high voltage, although I could be wrong. I would just try regular new alkaline batteries, or AAA rechargeable NiMH.
If it is only a 5mW pointer then you can get them for much cheaper like $8 or less. However a lot of 5mW pointers are over spec and therefore not "Eye Safe" because they are over 5mW and can actually be like 30mW or more.
Anything over 5mW your eye cannot blink and or you can't look away fast enough not to do damage from a direct hit, reflection etc.
With your laser it is possible it is :
1) Misaligned Crystal etc. = Actually putting out much higher but invisible power in mW. (Can be very dangerous)
2. Try new batteries
3. Some kind of problem with the driver possibly??
4. Just simply underspec.
Don't assume it is not problem #1 unless you have a LPM to test the actual power of your laser which will measure all light (invisible and green.)
Another thing you could try is taking a picture of the dot. I think you can see the IR as a pinkish glow on photos using cameras that don't have an IR filter built into them.
Remember though it could be dangerous to stare at the spot because there is invisible IR you are not aware of.