Fast Response Picoammeter

Fast-Response Liquid Crystal Microlens

Electrically tunable liquid crystal microlenses have attracted strong research attention due to their advantages of tunable focusing, voltage actuation, low power consumption, simple fabrication, compact structure, and good stability. They are expected to be essential optical devices with widespread applications. However, the slow response time of nematic liquid crystal (LC) microlenses has bee...

A 128-channel picoammeter system and its application on charged particle beam current distribution measurements.

A 128-channel picoammeter system is constructed based on instrumentation amplifiers. Taking advantage of a high electric potential and narrow bandwidth in DC energetic charged beam measurements, a current resolution better than 5 fA can be achieved. Two sets of 128-channel strip electrodes are implemented on printed circuit boards and are employed for ion and electron beam current distribution ...

1 Using Ohm ’ s Law to Calibrate a Picoammeter to 0 . 4 Pico - ampere Precision

Using Ohm's Law to Calibrate a Picoammeter to 0.4 Pico-ampere Precision

We present an experimental method based on Ohm’s Law to calibrate the Keithley 6485 picoammeter with the calibration error less than 0.4 pico-ampere (pA), which is specified as the highest sensitivity of this instrument. The maximum calibration difference between the measurement current and the calibration current in the picoammeter’s 2 nano-ampere (nA) range is 0.25 pA. This difference is far ...

Implementing Fast Cloth Simulation with Collision Response

This work details and implements efficient techniques for cloth simulation, both in the area of numerical simulation and the area of collision detection and response. Emphasis is put on the efficient implementation of implicit numerical methods with many improvements toward better realism, as well as computation simplicity. A constraint-based collision response scheme is adapted to this scheme ...