Sounds to me like they are creating a hologram at the boundary between the solidified resin and the surface of the resin tank. The actinic radiation term is simply a fancy way to say blue or UV light, which is what all SLA and SLA derivative printers are using. So, the light in the boundary area would be in the form of a hologram that conforms the light into tiny cones of light. The pointy parts of the cones touch the surface of the inner part of the resin tank and this is also where the solidified resin is touching. In between the pointy parts of the cones is where the liquid resin is coming in.
A hologram would be one way and is probably what their patent or patent application is referring to as a preferred embodiment. Note, I didn't see a patent or a patent application nor did I search for one, I'm simply assuming. A hologram would be one way but a simpler way and most likely what they are doing with their current machine since it doesn't appear that they are using coherent laser light, which is necessary to readily produce a hologram, would be to use a microlens array. Imagine a glass sphere. A glass sphere would have a very short focal length. Imagine the light going through the sphere and coming to a focal point a short distance from the surface of the sphere. After the rays of light pass through the focal point, they then diverge outwardly into a cone shape again. So, think of a glass sphere and the light coming out of it is in the shape of an hourglass. So, the focal point would be at the bottom surface of the resin tank. Now just imagine an array of microscopic spheres.
If that's what they're doing then it's a clever idea, however, they would still have the same problem as Carbon's CLIP technology of liquid resin transport. To expand on that, I'm talking about how, yes, they can print very rapidly when printing something like a 3D lattice because the resin doesn't' need to move very far to supply the forming part geometry. However, if they try to print something like a solid block that is the size of the XY build area they are going to be printing at the nearly the same speed as everyone else using SLA based methods and that is because the resin needs to travel from the outer edge to the center and that slows things down dramatically when printing large solid parts.
If you want to print extremely fast using SLA based methods think of a way to replenish the resin very quickly all over the build tank area. That is the key to success when factoring in all types of part geometry.