Abstract: A driving apparatus for a vibration-type actuator that applies an AC voltage to an electro-mechanical energy conversion element and generates a driving force between a vibration member and a movable member includes a voltage amplitude command unit configured to instruct an amplitude of the AC voltage, a pulse width command unit configured to monotonically increase a pulse width command and a change rate of the pulse width command according to an increase in a voltage amplitude command, and output a pulse width command, and a pulse signal generation unit configured, when a pulse signal that directly or indirectly generates the AC voltage is generated at the same frequency as the AC voltage to apply the AC voltage to the electro-mechanical energy conversion element, to generate a pulse signal having a pulse width corresponding to the pulse width command based on the pulse width command.
Abstract: A wave amplitude modulator for modulating a transmitted electromagnetic wave includes one or multiple self-gated capacitively coupled pair(s) of electron layers such as semiconductor or semimetal layers. Two electrical contacts are placed to each layer of electrons of the self-gated pair(s), and a power source is electrically connected to them. The power source, by varying the voltage applied between layers of electrons, tunes the electron density thereof, thereby adjusting the optical conductivity thereof, and the change in the optical conductivity of the layers of electrons causes an amplitude modulation of the transmitted electromagnetic wave passing through the capacitively coupled layers of electrons.
Type:
Grant
Filed:
June 21, 2012
Date of Patent:
September 16, 2014
Assignee:
University of Notre Dame du Lac
Inventors:
Berardi Sensale-Rodriguez, Huili (Grace) Xing, Rusen Yan, Michelle M. Kelly, Tian Fang, Debdeep Jena, Lei Liu
Abstract: An apparatus, system, and method are disclosed for modulating electric current. An electron source electrode 202 provides a flow of electrons in a partial vacuum environment 116. An ionizable gas 118 in the partial vacuum environment 116 forms positively charged ion particles in response to impact with the electrons from the electron source electrode 202. Application of a bias voltage differential between a first bias electrode 204 and a second bias electrode 206 in the partial vacuum environment 116 forms an electric field gradient in a path of the flow of electrons. A collector electrode 208 in the partial vacuum environment 116 collects more electrons than ion particles when a collector electrode input voltage 106 is above a threshold, and collects more ion particles than electrons when the collector electrode input voltage 106 is below the threshold.
Type:
Application
Filed:
June 21, 2012
Publication date:
April 17, 2014
Applicant:
RESEARCH TRIANGLE INSTITUTE, INTERNATIONAL
Abstract: A wave amplitude modulator for modulating a transmitted electromagnetic wave includes one or multiple self-gated capacitively coupled pair(s) of electron layers such as semiconductor or semimetal layers. Two electrical contacts are placed to each layer of electrons of the self-gated pair(s), and a power source is electrically connected to them. The power source, by varying the voltage applied between layers of electrons, tunes the electron density thereof, thereby adjusting the optical conductivity thereof, and the change in the optical conductivity of the layers of electrons causes an amplitude modulation of the transmitted electromagnetic wave passing through the capacitively coupled layers of electrons.
Type:
Application
Filed:
June 21, 2012
Publication date:
December 26, 2013
Applicant:
UNIVERSITY OF NOTRE DAME DU LAC
Inventors:
Berardi Sensale-Rodriguez, Rusen Yan, Huili (Grace) Xing, Michelle M. Kelly, Tian Fang, Debdeep Jena, Lei Liu