Search results
Results from the WOW.Com Content Network
The flicker fusion threshold, also known as critical flicker frequency or flicker fusion rate, is the frequency at which a flickering light appears steady to the average human observer. It is a concept studied in vision science , more specifically in the psychophysics of visual perception .
Flicker perception. Binocular summation can increase the critical flicker fusion rate (CFF) which is the highest perceivable flicker rate before the image appears continuous. The CFF is increased when both eyes see the same flicker, and it is decreased when the flicker for one eye is out of phase with the other.
Up to about 80 Hertz or the flicker fusion threshold it is called visible flicker. From about 80 Hertz to 2000 Hertz it is called the stroboscopic effect (this article). Overlapping in frequency, but from 80 Hertz up to about 6500 Hertz a third effect exists called the phantom array effect or the ghosting effect , an optical phenomenon caused ...
Modern shutters are designed with a flicker-rate of two times (48 Hz) or even sometimes three times (72 Hz) the frame rate of the film, so as to reduce the perception of screen flickering. (See Frame rate and Flicker fusion threshold.) Higher rate shutters are less light efficient, requiring more powerful light sources for the same light on screen.
In visual perception, flicker is a human-visible change in luminance of an illuminated surface or light source which can be due to fluctuations of the light source itself, or due to external causes such as due to rapid fluctuations in the voltage of the power supply (power-line flicker) or incompatibility with an external dimmer.
What links here; Related changes; Upload file; Special pages; Permanent link; Page information; Cite this page; Get shortened URL; Download QR code
Cones temporal resolution: from 10 to 15 ms [2] (therefore their actual flicker threshold should be in the 100 to 66 Hz range, and not a mere 60 Hz, which is why CRT screens, that have a response time of 4 nanoseconds, flicker at a refresh rate of 60 Hz).
A refresh rate of 60 Hz on most screens will produce a visible "flickering" effect. Most people find that refresh rates of 70–90 Hz and above enable flicker-free viewing on CRTs. Use of refresh rates above 120 Hz is uncommon, as they provide little noticeable flicker reduction and limit available resolution.