Custom ray tracing intersection in GPU

I want to conduct a ray tracing intersection query but I need to accelerate the task using the GPU. The reason is that I’m going to do this task for each pixel in a render target (let’s say 1024X1024).
The idea is to create a 2D texture that represent some sort of scan.

Imagine an actor with a scanner that scans 2D plane in front of it. in the texture, each pixel will represent a position in the plane, and a ray will detect all the intersection between that pixel and the scanner.

So basically I need to conduct 1024X1024 ray tracings for intersection.

Can anyone point me into the right direction on where to start looking for it?

If anyone still interested, I made a tutorial on how to create a customer ray trace shader