Polygraph instrument and accessories
Different components of the polygraph | Lie detector parts
There are a few polygraph instrument manufacturers in the market and most of them are US based. B.E.A.R. FORENSICS uses a variety of polygraph instruments from different producers to ensure that we are technically savvy to address our client’s needs. All instruments have proven to be reliable and we have had the opportunity to test the provider’s technical support.
Although each Polygraph Examiner has preferences, it is the policy of B.E.A.R. FORENSICS that its Polygraph Examiners remain versatile and flexible and must be fluent with every instrument in our inventory.
We will explain the main parts of a modern polygraph. Polygraph manufacturers might change but the accessories and results will basically be the same.
Components of a modern polygraph instrument
A modern polygraph instrument typically consists of :
- Data Acquisition System (DAS) which is the system that acquires the data from the accessories and translates it into analyzable information. This data can then be read and interpreted by a computer and Polygraph Examiner
- Pneumographs which record respiratory activity
- Blood Pressure Cuff which records cardiovascular activity
- Galvanometers which record sweat gland activity
- Other accessories can be used to improve readings like for example – Activity Sensor, Plethysmograph
A modern polygraph instrument saves information in a digital format contrary to the analog instruments that used to print the readings on moving paper.
Polygraph producers have their own proprietary software which comes with the polygraph instrument. The physiological collection algorithms do pretty much the same thing and there are not many differences among polygraph instrument brands.
Some instrument providers have been working on making life easier for polygraph examiners helping in the elaboration of, for example, exam reports.