We use a Arri Laser Film recorder. Wildly expensive, maintenance is very expensive, records to a limited number of filmstocks and ONLY within the Cineon Specified 0 to 2.4 dmin to dmax range (i.e., designed for color negative stocks; b&w output is limited to green channel only). Others such as the Lasergraphics (no longer offered on their website) could record up to 4.0 dmax, based on a CRT target.
You could, in theory, use any 2K capable display to build a real-time film recorder; the Cinevator being a very early, commercial variant that ran only at HD resolution, but with the decline of film projection, there hasn't been much or any advance in that area in some time. I used a Cinevator via the LA Technicolor Lab to output short sections of a film I digitally restored, and it looked pretty good, but no where near the quality of a 2/4K dedicated film recorder. The advantage of the Cinevator was direct output to positive film (print) AND the ability to record the sound track simultaneously. A sad case of technology arriving too late to fill a need gap in the production pipeline...
Its a rabbit-hole many a enthusiast has dropped-down, but few have ever made it to the finish line...