The LX4000 and LX5000 systems represent significant milestones in the evolution of polygraph technology. Developed by Lafayette Instrument Company, these systems have been pivotal in enhancing the functionality and reliability of polygraph examinations across various operational settings.
Introduction and Historical Context
The LX4000 was first introduced in 2002, equipped with sophisticated data acquisition capabilities tailored for polygraph examinations. Initially, the system featured two types of circuits: skin-conductance and skin-resistance, with the latter being utilized primarily due to its applicability in real-world settings. The original skin-resistance circuit had a measurement capability from 10 kilohms to 1 megohm, with a subject current of 3.6 microamps. However, field feedback suggested a need for a broader measurement range to accommodate the diverse conditions encountered during field polygraph tests. In response, Lafayette Instrument Company enhanced the LX4000 in 2004, expanding its resistance range to 2 megohms and increasing the current to 10 microamps.
Technological Enhancements and Modifications
This modification led to the development of an auxiliary circuit board, known as a daughter card, which was integrated into the LX4000’s main unit to handle the increased capabilities. This card was offered to existing customers and included in new units produced after 2006. The implementation of the daughter card allowed Lafayette to swiftly respond to new production demands and update existing units, showcasing their commitment to adaptability and customer satisfaction.
The LX5000 was introduced in 2008 as a response to customer interest in a modular system that could potentially support wireless connections between the data acquisition system (DAS) and the examinee. Although the market later moved away from a strong demand for wireless functionality, the LX5000 remained popular due to its versatile design, which accommodated both skin-conductance and skin-resistance circuits with adjustable modes.
Safety and Reliability
Safety has always been paramount for Lafayette Instrument Company. Both the LX4000 and LX5000 operate at low voltages, well within the safe limits set by international safety standards such as IEC 60601-1, which considers any voltage under 60 volts (DC) safe. This ensures that both systems pose no risk of electric shock to either the examiner or the examinee, affirming Lafayette’s commitment to safety.
Firmware and Hardware Updates
Significant firmware updates were implemented to expand the systems’ operational capabilities. For instance, firmware changes were necessary to adapt the LX4000’s processing power to handle the expanded measurement range. These updates required units to be returned for factory servicing, highlighting Lafayette’s dedication to maintaining high performance and functionality.
Customer-Centric Developments and Future Outlook
Lafayette has continued to refine their designs based on user feedback, addressing specific operational challenges such as the potential for system disconnections during long periods of use. For example, changes to the LX4000’s design in 2009 and 2010, referred to internally as LX4000A and LX4000B, focused on manufacturing efficiencies and expanded sensor capabilities respectively, enhancing overall system stability and functionality.
The journey of the LX4000 and LX5000 not only reflects Lafayette Instrument Company’s innovation in the polygraph field but also their proactive approach to customer feedback and technological advancement. With over five decades of experience, Lafayette remains at the forefront of the polygraph industry, continuing to innovate and provide advanced solutions that meet the complex needs of their clients.
For further details, questions, or feedback on the LX4000 and LX5000 systems, Lafayette Instrument Company encourages direct communication through their designated contacts and welcomes engagement from the polygraph community.
Contact Information:
- Chris Fausett, VP Polygraph and Sales: [email protected]
- Jennifer Rider, VP & CIO: [email protected]
- Brent Smitley, Engineering Manager: [email protected]
- Raymond Nelson, Research Specialist: [email protected]
- General Inquiries: [email protected]
