A laptop display is very dim and can only be read at certain angle, what might be the problem?

Some few things to consider are 

1. Check the display settings using the keyboard 

2. The notch under the lid of the computers although could be in older systems

3. The LCD inverter could be damaged or faulty

4. Connect an external monitor to troubleshoot for further diagnosis

Apologies, but simple things first.

This may sound funny, but is there a privacy screen over the laptop display?

Check the brightness Adjustment and bring it to full brightness. If it is still dim, then replace your LCD. your laptop might have been expossed directly to sunlight for some time and in extreme heat.

there is three thing should be give this problem

1: Motherboard

2: LCD

3: Light button

this problem occure due to the relosution problem on your laptop else the problem of your screen. soon your laptop screen gone, once you check the technician it may be the problem edginh the laplot with heavy things, so please cheak from the technician its simple one or your screen on going to coma.