CW6 System

CW6TechEn is a leading provider of continuous-wave optical imaging systems worldwide. Continuous-wave (CW) light is used to obtain quantitative estimates of relative changes primarily in oxy and deoxy-hemoglobin during functional activity. To provide a robust solution, we have developed, with the help of the Optics Division at the MGH-Martinos Center for Biomedical Imaging, a number of advancements that enhance the technology and improve ease of use for researchers and clinicians.

CW technology is used widely for functional measurements because of the large number of source and detector channels; low cost; safe, non-ionizing radiation; portability; and ease of setup for patient use. Meaningful measurements are achieved quickly with one to five minutes of data.

We provide advanced CW technology and head probe systems that offer high spatial resolution and the flexibility to accommodate a wide range of unique research studies. We also provide a range of advanced software options.


The primary advantages of our continuous-wave CW6 technology over other existing systems are the number of effective channels, the availability of raw data output at high speed, the ease of use and flexibility, and the software.

We have developed the novel, real-time DSP-based CW6 and CW6 CE systems. The CW6 provides real-time data acquisition and display, which have dramatically advanced the state of NIRS technology. Continuous, real-time data acquisition of the entire head is achieved by incorporating up to 32 lasers and 32 detectors in this new CW6 system architecture, along with novel software and DSP processing. The very fast, real-time output sample rate of the CW6 offers significantly higher resolution than previous systems, and generally provides for superior dynamic range.

The CW6 provides more signal channels than almost any other system by using frequency modulation or encoding of each laser source. Through modulation of the sources and demodulation of the detected signals, our systems allow each detector to “see” each laser source. With our CW6 32x32 system, it is possible to acquire data for 32x32 or 1024 individual raw signal measurements. The primary benefit of more signal channels is improved spatial resolution and dense-array whole-head coverage.

The demodulated output sampling rates are over 50 Hz, depending on the number of laser and detector channels. Typically, sample rates are 25 Hz. The dynamic signal range is exceptional and, because we use frequency encoding of lasers, good spatial resolution is achieved. The spatial resolution can be further improved in some studies through the use of dynamic gain state switching. State switching allows nearest neighbor detectors to see activation from more distant lasers.

We also provide up to 8 BNC connectors for auxiliary signals and triggers from external devices, using a 5-V pulse. This allows integration of E-Prime, pulse oximeters, and respiration and other physiological instruments with the CW6 by saving the data in the same file for display and analysis.

Ease of Use

Easy-to-use CW6Because our CW6 is a real-time instrument, it is especially important that the data acquisition software be easy to use. We have designed the software with this in mind. The data acquisition software packaged with the CW6 shows functional display, laser control, detector control and gain settings. In addition, it allows you to toggle between 690nm and 830nm, by laser and detector pairings.

The software has adjustable control settings that facilitate easy changes in display time as well as in intensity in dB. Users may enlarge signals of interest to view the cardiac and hemodynamic signals, all in real-time. The software displays are intuitive and have ease of use for CW6. The software generates *.NIRS files and is compatible with HOMER, and HOMER 2, an open source software developed by Dr. David Boas at Massachusetts General Hospital. HOMER software is used for data analysis and imaging functions.


TechEn Customer Support for CW6 Systems

We recognizes that our clients are early adopters of new technology and may need to ask questions and require support. We work to establish a collaborative relationship with our clients and provide ongoing support to help achieve successful research.

We provide this support through telephone calls, emails and online sessions - our goal is to help our clients become successful in their research, enabling medical advancements through development of new applications and tools. After this initial period, most researchers operate quite independently.

System Flexibility Increases Ease of Use and Adaption for New Techniques

Our system is flexible and designed for ease of use.

CW6 HeadcapAn essential advantage of our CW6 systems is the integration of advanced technology with comfortable and flexible optical head cap or head band systems. By allowing an array of lasers and detectors to be placed easily and comfortably, the systems facilitate unique research endeavors. Our flexible system allows significantly more measurement channels in an array, and in varied montages, than comparable systems.

Other significant advantages of CW6 flexible systems include:

  • short-distance probes
  • special optical fibers
  • specialized probe arrays
  • low-profile optodes
  • multi-modal head caps and fibers
  • Supplemental Source Unit for 32 additional emitters

Custom Development for Specialized Needs

We develop custom instruments, head gear, optical probes and software to support specialized requirements. As an example, we have developed an add-on, supplemental source unit (SSU), allowing connection of an additional 32 sources. Also, our flexible laser modular laser source cards enable the study of special enzymes with multiple wavelengths, including 690, 785, 808, 830 and 904 nm.