create a cirlce from laser point without a motor

[sefiroths]

Hi, I'd like to make a circle beam from laser point without a motor. This is a tower that project a circle on the ground.
I thought that if I place a laser under a metallic sphere or a cone could work? or the laser is so precise that is reflected exacly vertical?
Perhaps should a have a divergent lens and a plane mirror over it?
This is for a personal game project, so it must be cheap
Thanks

 

[RedCowboy]

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[steve001]

An Axicon lens will do what you want.

 

[RedCowboy]

I was also going to suggest an Axicon lens but I remembered OP wanted it to be inexpensive, however if you know of a source for inexpensive Axicon optics, I would like to buy some myself.

 

[sefiroths]

yes inexpensive, however sounds interesting, perhaps can I make it my own with a 3d printer if I make a lens with tranparent plastic?
(in my country Axicon not arrive)