Abstract: Systems, apparatuses, and methods for realizing a peak-force scattering scanning near-field optical microscopy (PF-SNOM). Conventional scattering-type microscopy (s-SNOM) techniques uses tapping mode operation and lock-in detections that do not provide direct tomographic information with explicit tip-sample distance. Using a peak force scattering-type scanning near-field optical microscopy with a combination of peak force tapping mode and time-gated light detection, PF-SNOM enables direct sectioning of vertical near-field signals from a sample surface for both three-dimensional near-field imaging and spectroscopic analysis. PF-SNOM also delivers a spatial resolution of 5 nm and can simultaneously measure mechanical and electrical properties together with optical near-field signals.

Abstract: The present disclosure discloses a light-emitting diode (LED) driver comprising a controller and a main circuit. The controller is configured to receive a dimming signal for dimming an LED load and use a current hysteresis control to generate a control signal, wherein a hysteresis width of the current hysteresis control varies with the dimming signal. The main circuit comprises a front-end stage configured to receive an AC input voltage and output a DC bus voltage, and a back-end stage configured to receive the bus voltage and responsive to the control signal, output a desired drive current through output terminals to the LED load so as to produce a target illumination intensity. The present disclosure widens the dimming depth of analog dimming in the LED dimming technology, achieves deep dimming and satisfies good dimming linearity in the entire dimming range.

Abstract: The present disclosure discloses a light-emitting diode (LED) driver comprising a controller and a main circuit. The controller is configured to receive a dimming signal for dimming an LED load and use a current hysteresis control to generate a control signal, wherein a hysteresis width of the current hysteresis control varies with the dimming signal. The main circuit comprises a front-end stage configured to receive an AC input voltage and output a DC bus voltage, and a back-end stage configured to receive the bus voltage and responsive to the control signal, output a desired drive current through output terminals to the LED load so as to produce a target illumination intensity. The present disclosure widens the dimming depth of analog dimming in the LED dimming technology, achieves deep dimming and satisfies good dimming linearity in the entire dimming range.