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2 Nanowire-Based Optical Sensor
Published in Tarun Kumar Gangopadhyay, Pathik Kumbhakar, Mrinal Kanti Mandal, Photonics and Fiber Optics, 2019
Aniruddha Mondal, Anupam Ghosh
Rise time is defined as the time difference between the point at which the detector has reached 10% of its peak output and the point at which it has reached 90% of its peak response, when a very short pulse of light irradiates it. The fall time is defined as the time between the 90% point and the 10% point on the trailing edge of the pulse waveform. This is also called the decay time. We should note that the fall time may be different numerically from the rise time. Of course, light sources are not turned on or off instantaneously. To make accurate measurements of rise time and fall time, the source used for the measurement should have a rise time much less than the rise time of the detector being tested. Generally, one should use a source whose rise time is less than 10% of the rise time of the detector being tested. The intrinsic response time of an optical detector arises from the transit time of photogenerated charge carriers within the detector material and from the inherent capacitance and resistance associated with the device.
Dosimetry in Electroporation-Based Technologies and Treatments
Published in Marko Markov, Dosimetry in Bioelectromagnetics, 2017
Eva Pirc, Matej Reberšek, Damijan Miklavčič
Exponential decay pulses (Figure 12.6a) are best described by their maximum value, AMAX, and time constant, τ. The value of time constant depends on circuit output stage characteristics. It is defined as the time maximum amplitude AMAX, which drops to 37% of AMAX. Square wave pulses are described with amplitude at high stage (that is choose to best fit the high level) and time tFWHM (Full Width at Half Maximum-FWHM). tFWHM is best described as the time passed between when the pulse reaches 50% of maximal amplitude at the rising and falling phase. Other pulse shapes are best described if we define their rise (tR) and fall times (tF) and maximum amplitude AMAX. Rise time is time required for a pulse to rise from 10% to 90% of its steady value. Similarly, fall time is the time taken for the amplitude of a pulse to decrease from a specified value (usually 90% of the peak value exclusive of overshoot or undershoot) to another specified value (usually 10% of the maximum value exclusive of overshoot or undershoot) (Reberšek et al., 2014).
Sequential Logic Circuits
Published in M. Michael Vai, Vlsi Design, 2017
In addition to its frequency and duty cycle, a clock signal is qualified by considering its rise time and fall time. Fig. 5.2 shows the definitions of rise time and fall time. Rise time is the time the clock signal takes to go up from 10% to 90% of its high value. Fall time is the time the clock signal takes to go down from 90% to 10% of its high value. A good clock signal must have reasonably fast rise time and fall time (typically below 1/10 of the clock cycle time).
Multimodal sensor to measure the concurrent electrical and mechanical activity of muscles for controlling a hand prosthesis
Published in Instrumentation Science & Technology, 2020
Neeraj Sharma, Alok Prakash, Ajay Kumar Sahi, Neeraj Sharma, Shiru Sharma
The response time of the envelopes produced by the sensor was estimated in terms of the rise and fall times that were evaluated for obtained EMG and FMG envelopes by the sensor considering each muscular contractions in the percentage of maximum voluntary contraction. Rise time was calculated as the time required to rise the envelope from 10% to 90% of its largest value. Conversely, fall time was evaluated as the time needed by the envelope to fall from 90% to 10% of its maximum value.[33]Figure 6 describes the calculation procedure of rise and fall times from EMG and FMG envelopes.
Fast response time of micropixels with in-plane switching of positive liquid crystals using crossed patterned electrodes
Published in Journal of Information Display, 2019
Clément Abélard, Aurélien Suhm, Benoit Racine, Umberto Rossini, François Templier
The main objective is to optimize the response time = rise time + fall time. The rise time can be easily reduced by increasing the addressing voltage. The fall time can be reduced by driving the turn-off electrodes. If the buried electrodes are addressed, however, and the 2nd-level electrodes are left in a floating state, no effect on the fall time will be observed. According to the electronic convention, for a normally black configuration, the rise time/turn-on time is defined as the transient time for the transmittance to rise from 10% to 90% of the maximum value, and vice versa for the fall time/turn-off time.