I have an LCD monitor and when i turn out the lights it gets darker and when I turn on the lights it gets brighter i need to know if its defective
Everyone gave good replies. I'll add you can usually turn off this feature, but I would leave it alone.
the monitor could have a light sensor that will automatically dim the monitor in low light conditions, and turn up the brightness in bright conditions. its not a defect its just friendly
LCDs are made for bright lit rooms if you got a cheap lcd it was a bad move if you had got a more expensive on none of this would of happened it is not a defect. you should of looked at the specs of the monitors you were looking at the higher the brightness and contrast ratio in the specs the better
Sounds like you have an LCD monitor with an ambient light sensor. If the dimming is that distracting, what you will want to do is go into the monitor's onscreen menu and see if there is a way to turn that feature off. I don't know what brand your monitor is so I can't really help you further. Just a thought: you may want to consider leaving it as is, since a darker monitor in a darker room will reduce eye strain :)