Design and construction of a closed loop phantom for skin-contact thermography.

We have designed and constructed a wearable device for skin-contact thermography [Giansanti D, Maccioni G. Development and testing of a wearable integrated thermometer sensor for skin-contact thermography. Med Eng Phys 2007;29(5):556-65] that uses 16 integrated silicon sensors with a thermal resolution of 0.03 degrees C and a spatial resolution of 1.6 x 10(-5)m(2). In order to perform a dynamic bench test, a thermographic phantom was designed and constructed that permits the imposition of 16 independent thermal waveforms to the device. The phantom was based on 16 small black bodies units designed with a 10(-4) m thin layer of black conductive gum. An infrared system was used in closed loop to correct in real time the error between the theoretical and the actual temperature imposed. The methodology proved to be adequate for bench testing the device. The difference between the imposed and the theoretical waveforms was never greater than 0.85 x 10(-2) degrees C in mean value, as measured with the infrared (IR) system.