Dynamic optical tomographic imager with optimized digital lock-in filtering

Joseph M. Lasker; James M. Masciotti; Yang Li; Chris Fong; Andreas H. Hielscher

doi:10.1117/12.728578

12 July 2007 Dynamic optical tomographic imager with optimized digital lock-in filtering

Joseph M. Lasker, James M. Masciotti, Yang Li, Chris Fong, Andreas H. Hielscher

Proceedings Volume 6629, Diffuse Optical Imaging of Tissue; 662903 (2007) https://doi.org/10.1117/12.728578
Event: European Conferences on Biomedical Optics, 2007, Munich, Germany

Abstract

We describe a new dynamic optical tomography system that is, unlike currently available analog instrumentation, based on digital data-acquisition and filtering techniques. At the heart of this continuous wave instrument is a digital signal processor (DSP) that collects, collates, processes, and filters the digitized data set. A digital lock-in filter that has been designed for this particular application maximizes measurement fidelity. The synchronously-timed processes are controlled by a complex programmable logic device (CPLD) that is also used in conjunction with the DSP to orchestrate data flow. Real-time data rates as high as 140Hz can be achieved. The operation of the system is implemented through a graphical user interface designed with LabVIEW software, Performance analysis shows very low system noise (~600fW RMS noise equivalent power), excellent signal precision (<0.04% - 0.2%) and long-term system stability (<1% over 40 min). A large dynamic range (~195dB) accommodates a wide scope of measurement geometries and tissue types. First experiments on tissue phantoms show that dynamic behavior is accurately captured and spatial location can be correctly tracked using this system.

Citation Download Citation

Joseph M. Lasker, James M. Masciotti, Yang Li, Chris Fong, and Andreas H. Hielscher "Dynamic optical tomographic imager with optimized digital lock-in filtering", Proc. SPIE 6629, Diffuse Optical Imaging of Tissue, 662903 (12 July 2007); https://doi.org/10.1117/12.728578

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available