You can move a piece 1 or 2 spaces in a single direction (1 east, or 2 east, but not 1 north east unless that was used as two moves). You could also rotate on your turn. Firing a laser was optional.
In Khet, you can move one piece 1 adjacent spot (any of the 8) or rotate (not both) and you always fired the laser.
The rules are different - and the rules are patented.
If you had different rules that weren't covered by the claims, it would be a different game.
Laser strategy game board - https://patents.google.com/patent/US20080054563A1/en - that's a different game that was patented after Khet.
https://youtu.be/4nQaWJEBFNk (and if you want to play a digital version https://store.steampowered.com/app/312720/Khet_20/ ) vs https://archive.org/details/laserch or https://archive.org/details/msdos_Laser_Chess_1994
They are different games with different rules.
Strategic board game https://patents.google.com/patent/US6981700B2/en
https://en.wikipedia.org/wiki/Arimaa
While that plays with animal pieces, there's a 1:1 mapping from traditional chess pieces to Arimaa pieces and it's played on the same board.
Yes. Very much it does. It's been 35 years since I played Laser Chess, so perhaps there are some minor differences in the rules. But it describes a game so close to Laser Chess that it immediately brought the game to mind.