Note: this has only been tested on Firefox browsers -- Chrome works, but does not always reach 240 Hz.
Supplemental website for the HPG 2019 short paper: Temporally Dense Ray Tracing by Pontus Andersson, Jim Nilsson, Marco Salvi, Josef Spjut, and Tomas Akenine-Möller.

Hang on, measuring monitor refresh rate...

Explanation: Here we show path traced images rendered at 32 samples per pixel. When the framerate is increased to 240 Hz (using the radio buttons below the image), the samples are perceived as (approximately) averaged, which again is a consequence of the integration effect of the human visual system and the display.

Desired frame rate: