Warm-up Time

Time before the internal circuit warms up. If warm-up is shorter than this time, the measured value shifts according to the change in the temperature of the internal circuit (initial drift).

Window Function

The FFT calculation assumes that the target waveform continues endlessly. Consequently, unless the calculated data is an integral multiple of one cycle, discontiguous points appear at the both ends of the calculated data. This results in the inclusion of unnecessary frequency components. The window function is a correction filter which gradually attenuates both ends to reduce the influence of the discontiguous points.

Withstand Voltage

Voltage which does not damage the instrument when applied between the input terminal and grounding, or between the input terminals. Note that this is not a voltage applied between the positive and negative sides of the input.

Withstanding pressure

The maximum pressure that can be applied to the pressure sensor. Applying pressure exceeding this value will cause the pressure sensitive element to lose its repeatability or to be damaged.

Word origin of Fθ lens (Scanning method)

With an ordinary convex lens, "L" (parallel beam height), as shown below, can be expressed by the following formula: L = f * tanθ where L=Height of parallel light (mm), t=Focal length of the lens (mm), θ=Angle from the center (rad)