MONARCH INSTRUMENT Nova-Pro IR 850, Инструкция по эксплуатации

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6.0 STROBE BRIGHTNESS
The strobe’s brightness depends on how wide the strobe’s flash pulse is;
the wider the pulse, the brighter the flash from the LEDs appears to be.
There is however, a downside to the wider pulses. All strobes work by
giving short bursts of light (the pulse width) at a rapid repetition rate (the
flash rate). Strobes rely on the persistence of the human eye (the ability to
remember and image) and its response to bright light to give an apparent
stop motion image. Imagine a shaft rotating at 6000 RPM or one rotation
every 1/100 of a second (10 msec). If the strobe flashes once every 10 msec
for a brief moment, the user sees the flash at the same spot in the rotation
of the shaft and the persistence of the eye remembers this until the next
flash making the shaft appeared to be stopped. As the target is rotating
there is some movement evident during the strobe flash. The longer the
flash duration, the more obvious the rotation is and this increases the blur.
The Lamp ON Mode does not have a brightness setting.
6.1 Calculating Blur
Blur can be calculated– if the shaft is turning at
6000 RPM, it takes 10 msec to complete one
revolution. If the strobe flash duration is 100
µsec (1/100 of a millisecond), the shaft will turn:
(flash duration/time per rotation) x 360°, which is
(.0001/.01) x 360 = 3.6°. So you will see the shaft
appear to move 3.6°.
As the flash pulse widens you will see greater
degrees of rotation which results in more blur
and a brighter perceived illumination (the LEDs
are on longer so the average light the eyes see is
greater). The trade off is blur versus brightness.
The further away the rotating point is from the
center axis the faster the tangential velocity and
the worse the blur appears to be.