3195results about How to "Control speed" patented technology

An oversampling pulse oximeter includes an analog to digital converter with a sampling rate sufficient to take multiple samples per source cycle. In one embodiment, a pulse oximeter (100) includes two or more light sources (102) driven by light source drives (104) in response to drive signals from a digital signal processing unit (116). The source drives (104) may drive the sources (102) to produce a frequency division multiplex signal. The optical signals transmitted by the light sources (102) are transmitted through a patient's appendage (103) and impinge on a detector (106). The detector (106) provides an analog current signal representative of the received optical signals. An amplifier circuit (110) converts the analog current signal to an analog voltage signal in addition to performing a number of other functions. The amplifier circuit (110) outputs an analog voltage signal which is representative of the optical signals from the sources (102). This analog voltage signal is received by a fast A / D converter (112) which samples the analog voltage signal to generate a digital voltage signal which can be processed by the digital signal processing unit (116). The fast A / D converter (112) operates at a rate sufficient to take multiple samples per source cycle and may have a sampling frequency, for example, of over 41 kHz. The digital signal processing unit (116) implements software for averaging the samples over a source cycle for improved measurement consistency, improved signal to noise ratio and reduced A / D converter word length.

Phacoemulsification apparatus includes a phacoemulsification handpiece having a needle and an electrical circuitry for ultrasonic vibrating the needle. A power source provides pulsed electrical power to the handpiece electrical circuitry and an input is provided for enabling a surgeon to select an amplitude of dislighted pulses and a pulse width. A control system and pulse duty cycle is provided for controlling the off duty cycle to insure heat dissipation before a subsequent pulse is activated, including a foot pedal switch.

An electrostatic air cleaning device includes an array of electrodes. The electrodes include corona electrodes connected to a suitable source of high voltage so as to generate a corona discharge. Laterally displaced collecting electrodes include one or more bulges that have aerodynamic frontal “upwind” surfaces and airflow disrupting tailing edges downwind that create quite zones for the collection of particulates removed from the air. The bulges may be formed as rounded leading edges on the collecting electrodes and / or as ramped surfaces located, for example, along a midsection of the electrodes. Repelling electrodes positioned between pairs of the collecting electrodes may include similar bulges such as cylindrical or semi-cylindrical leading and / or trailing edges.