Open-source Shader Beam software released, gives you CRT-like experience on high-refresh monitors
ShaderBeam is a new open-source Windows overlay that runs Blur Busters BFI and CRT Beam Simulation shaders on top of your desktop and fullscreen games. The first public beta, v0.1, was released on December 28, 2025.
The main goal for this project is motion clarity. CRTs look clearer in motion because they behave like an impulse display: each pixel lights up briefly as the beam scans, then it fades, instead of holding a full frame steady for the whole refresh. On modern LCD and OLED panels, that “sample-and-hold” behavior creates blur when your eyes track moving objects, even if pixel response times are fast.
ShaderBeam tries to recreate the CRT “ rolling scan plus phosphor fade ” timing in a GPU shader, which can make 60 fps content look cleaner on 120 Hz to 480 Hz displays. Blur Busters describes this approach as a way to reduce motion blur with softer flicker than classic black frame insertion, but it scales with refresh rate and needs multiple subframes per content frame to work well. In other words, it works better with high refresh rate monitors.
Shader Bream (left) and CRT Simulation (right)
ShaderBeam is fullscreen-only, requires VSync, and it is sensitive to timing and GPU scheduling, so missed frames can show up as irregular flashing. So what’s recommended is to use two graphics cards , one fully devoted to Shader Beam. Iti s also suggested to turn off off HAGS, VRR (G-Sync and FreeSync), and HDR, and it warns that multi-monitor setups and other overlays can make things worse.
This is why enthusiasts keep chasing CRT behavior even on modern panels. You can get the sharp motion of classic displays without hunting for aging tubes, dealing with size and weight, or accepting analog-era quirks, while still using current games and video pipelines. ShaderBeam is also a practical “proof you can run it” wrapper around the CRT Beam Simulator work that started as a shader and demo, and it points toward more motion-clarity options in software stacks that already rely on high refresh rates.
Source: Shader Beam (Github) , CRT Simulation (Blur Busters)
