Here is one of many ways to re-create this:
-Create 4 black solid layers. Add a Lens Flare to them. Place one flare in the bottom right corner. On another solid make the lens flare on the fare right middle. And then make the third color solid’s lens flare on the top. Fell free to change there color if you want. Having different color flares will look closer to what you are after. Add a Ramp behavior to the last black solid and make sure it is on the bottom of the other layers. Make the top a light gray and the bottom a dark gray. Add an Adjustment layer above the black solids. Add a Fast Blur to it and set it to around say 60. That will make the lens flares blurry. Select all of the layers and create a pre-comp.
Add another color solid and make it white. Add a mask to it and make is an oval shape. Make the feather big like 250 or more. Move it so it is where the floor would be.
As for the light line. I use Optical Flares from Video Copilot. You can make custom flares where you can make a string of 3D Iris Rings and change there shape type to Polygon.
Hope this helps and best of luck.
Stephen Smith
Utah Video Productions
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