Try an external keyboard. Turn off the laptop, connect the external keyboard and then turn the laptop on. If the attached keyboard is the problem (which can happen), then the external keyboard should allow you to type and get in. You may also need to attache an external mouse. Once this is done, and if it worked to get you in, then I would try the following...
1. Uninstall the keyboard driver.
2. Reboot the computer (without reinstalling the driver).
3. When it restarts, it should reinstall the driver on its own.
If this doesn't work, you may wish to try connecting/reconnecting an external keyboard and see if it works fine. If it does, then it could be the keys themselves that are the issue.
You may also want to try updating the Synaptics Driver if the above doesn't help.
If, however, the keyboard isn't the issue, and you are just trying to bypass the lock screen, this we cannot assist with. Please read the following thread...
http://www.tomsguide.com/forum/id-2317968/read-passwords-lock-codes-pin-numbers.html