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By definition, the CFFF is "the highest or lowest temporal frequency, at a given percentage modulation, that can be resolved." (Schwartz, Visual Perception, 3rd ed.) In other words, the limits of distinguishing a flashing light from a steady one (at both the slow and fast end limits). Percentage modulation is calculated using the amplitude of the luminance of the light source, and the time-averaged luminance of said light source. In other words, the difference between the brightest/dimmest points in the cycle, averaged over the speed it takes to vary between the two points. Percentage modulation is used to calculate Relative Sensitivity, which is (1 / Percentage Modulation). For example: A lightbulb powered by Alternating Current (AC) is flickering. This is not visible to the normal human eye for two reasons (both variables in the definition of CFFF.) The temporal frequency of the AC in most American homes is 60Hz. The high temporal frequency cut-off for human sensitivity varies, and some cells are known to be sensitive to frequencies as high as 250 Hz, but for general daytime vision, it is lower than 60Hz. Also, the percentage modulation of a light bulb is low, since the change in brightness of the filament is very small. Relative sensitivity is the inverse of the percentage modulation. For flicker to be visible, a light source must have a relatively large change in level of brightness, and flicker at a rate within the human sensitivity range, somewhere between 2 and 50Hz. By definition, the CFFF is "the highest or lowest temporal frequency, at a given percentage modulation, that can be resolved." (Schwartz, Visual Perception, 3rd ed.) In other words, the limits of distinguishing a flashing light from a steady one (at both the slow and fast end limits). Percentage modulation is calculated using the amplitude of the luminance of the light source, and the time-averaged luminance of said light source. In other words, the difference between the brightest/dimmest points in the cycle, averaged over the speed it takes to vary between the two points. Percentage modulation is used to calculate Relative Sensitivity, which is (1 / Percentage Modulation). For example: A lightbulb powered by Alternating Current (AC) is flickering. This is not visible to the normal human eye for two reasons (both variables in the definition of CFFF.) The temporal frequency of the AC in most American homes is 60Hz. The high temporal frequency cut-off for human sensitivity varies, and some cells are known to be sensitive to frequencies as high as 250 Hz, but for general daytime vision, it is lower than 60Hz. Also, the percentage modulation of a light bulb is low, since the change in brightness of the filament is very small. Relative sensitivity is the inverse of the percentage modulation. For flicker to be visible, a light source must have a relatively large change in level of brightness, and flicker at a rate within the human sensitivity range, somewhere between 2 and 50Hz.

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How does fusion frequency relate to tetanus?

The fusion frequency is the minimum stimulus required to elicit tetanus in a muscle. For example, the fusion frequency can be given in terms of volts (V), or it can be given in terms of whatever units by which the applied stimuli are being measured.


What is the operating frequency of LED?

The operating frequency of LED lights can vary depending on the design and manufacturer, but typically ranges from a few kilohertz to several megahertz. LED lights can be driven by both DC and AC currents, and the frequency at which they operate determines the flicker rate of the light.


What is center frequency?

Center frequency refers to the frequency at the midpoint between the upper and lower limits of a bandpass filter or a communication channel. It is a critical parameter in signal processing, telecommunications, and radio frequency engineering as it represents the frequency around which most of the signal energy is concentrated.


What is the function of bulb in frequency of ac mains by electrically vibrating rod?

The bulb in the frequency of AC mains by electrically vibrating rod acts as a visual indicator of the frequency of the vibrations produced by the rod. As the rod vibrates at the frequency of the AC mains, the bulb will flicker or light up in synchronization with the vibrations, providing a way to visually observe the frequency.


Defn of critical or whirling speed?

Critical speed, also known as whirling speed, refers to the rotational speed at which a system becomes dynamically unstable, leading to vibration and potential failure. This can occur in rotating machinery or structures when the natural frequency of the system matches the excitation frequency. It is important to avoid operating equipment near its critical speed to prevent structural damage and maintain operational safety.

Related Questions

What indicates strong mental health?

A quck test that differtiates those under great stress from more normal people is the CFF (critical frequency fusion).


Why do lights flicker on camera and how can this issue be resolved?

Lights flicker on camera due to a mismatch in the frequency of the light source and the camera's frame rate. This issue can be resolved by adjusting the camera's frame rate or using lighting sources with a consistent frequency.


What has the author Vernon Lemont Miller written?

Vernon Lemont Miller has written: 'The critical frequency limen for visual flicker in children between the ages of 6 and 18' -- subject(s): Left- and right-handedness, Physiological optics, Vision


For satellite communication the frequency should be less than critical frequency?

For satllite communication the frequency should not be less than the critical frequency because in satellite communicaton high frequency is needed which is reflected by satellite but not by the ionosphere.


How does fusion frequency relate to tetanus?

The fusion frequency is the minimum stimulus required to elicit tetanus in a muscle. For example, the fusion frequency can be given in terms of volts (V), or it can be given in terms of whatever units by which the applied stimuli are being measured.


Why do LED lights flicker on camera?

LED lights can flicker on camera because of the difference in frequency between the light's flickering and the camera's frame rate, causing a mismatch that is captured by the camera.


Word in the solar system that starts with f?

flare, fusion, falling star, frequency


What is the operating frequency of LED?

The operating frequency of LED lights can vary depending on the design and manufacturer, but typically ranges from a few kilohertz to several megahertz. LED lights can be driven by both DC and AC currents, and the frequency at which they operate determines the flicker rate of the light.


What is formula to find maximum usable frequency?

I suppose the formula is: MUF=critical frequency/cosine(angle of incidence). ex:The MUF for an angle of incidence of 60 deg and a critical frequency of 60MHz will be MUF=60 * 10^6/cos(60) =120 MHz By VSR


2005 silverado dash lights flicker?

why do my lights flicker and interior lights flicker


When was The Flicker created?

The Flicker was created in 1965.


What is center frequency?

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