Measurement and depth estimation of thermally active buried heating source in stacked die architectures were performed by using the phase image obtained from infrared microscopic sensor. Highly sensitive infrared images were measured and post-processed using a lock-in method. By applying the lock-in method to infrared images, the detection sensitivity and signal to noise ratio were enhanced by ...

This paper presents a methodology to determine all-digital phase-locked loop (ADPLL) circuit variables based on required design specifications, including output phase noise, fractional spur and locking time. An analytical model is developed to characterize the effects of different noise sources on ADPLL output phase noise and fractional spur. Applying the proposed noise model, circuit variables...

OBJECTIVES The purpose of this study was to explore phase reset of 3-dimensional current sources in Brodmann areas located in the human default mode network (DMN) using Low Resolution Electromagnetic Tomography (LORETA) of the human electroencephalogram (EEG). METHODS The EEG was recorded from 19 scalp locations from 70 healthy normal subjects ranging in age from 13 to 20 years. A time point ...

A versatile, low-cost, digital signal processor (DSP) based lock-in module with external reference is described. This module is used to implement an industrial spectrophotometer for measuring spectral transmission and reflection of automotive and architectonic coating glasses over the ultraviolet, visible and near-infrared wavelength range. The light beams are modulated with an optical chopper....

CHRISTENSEN, JAMES, AND RICHARD L. HAUSER. Longitudinal axial coupling of slow waves in proximal cat colon. Am. J. Physiol. 22 l(1) : 246-250. 197 1 .-We studied spreading patterns of electric slow waves of circular muscle in longitudinal axis of cat colon. The colon, opened lengthwise, was pinned flat, serosa down, in a bath equilibrated with 957, OQ--5y0 CO2 at 36.5-37.5 C. Six volume-recordi...

BACKGROUND Prosthesis suspension systems can alter the distribution of pressure within the prosthetic socket. This study evaluates a new suspension system for lower limb prostheses, and aims to compare the interface pressure and amputees' satisfaction with the new system compared with a common prosthetic suspension system (pin/lock). METHODS Ten transtibial amputees walked at a self-selected ...

CHRISTENSEN, JAMES, AND RICHARD L. HAUSER. Circumferential coupling of electric slow waves in circular muscle of cat’ colon. Am. J. Physiol. 221(4): 1033-1037. 1971 .-The cat colon, opened along the antimesenteric border, was spread, serosa down, in a bath of Krebs solution. Six volume-recording electrodes, 5.8 mm apart, were placed on the circular muscle layer exposed by removal of the mucosa ...

In this lab, we explore the principles of the use of a lock-in amplifier, using a He-Ne laser, light chopper, and a photodiode as the lock-in input. We explain and use the concepts of phase sensitive detection, dynamic reserve, and time constants to determine both the range of linearity of the photodiode in use, as well as the frequency response of the photodiode. Furthermore, we determine whet...

An alternative adaptive-optic controller, using both flow control and a phase-lock-loop control strategy, has been designed to overcome bandwidth limitations inhibiting current adaptive-optic controllers. A discrete-vortex code and weakly compressible model were used to simulate high-speed shear layer adaptive-optic corrections based upon the proposed phase-lock-loop controller given a range of...

Stanford Research Systems phone: (408)744-9040 www.thinkSRS.com Lock-in amplifiers are used to detect and measure very small AC signalsall the way down to a few nanovolts. Accurate measurements may be made even when the small signal is obscured by noise sources many thousands of times larger. Lock-in amplifiers use a technique known as phase-sensitive detection to single out the component of t...