Increase and decrease brightness of screen in kali linux

First open the terminal and type

cd /root/Desktop/
wget http://ftp.de.debian.org/debian/pool/...
dpkg -i xcalib_0.8.dfsg1-2_amd64.deb

If you want to dim or decrease the light then press in terminal
xcalib -co [how much percent you want to increase] -a

xcalib -co 40 -a


For reset the brightness

xcalib -c