This paper presents the design, fabrication and evaluation of an optical readout infrared thermal imaging sensor for human detection using vacuum evaporated Eu(TTA)3 phosphor. Eu(TTA)3 is served as an infrared (IR)-to-visible converter, which emits temperature dependent luminescence under specific ultraviolet (UV) excitation. The temperature sensitivity of luminescence intensity from Eu(TTA)3 was measured as about -2.1%/oC. An optical readout system was designed to measure the luminescence changes of the sensor pixels. Eu(TTA)3 on the sensor pixels is excited by a light emitting diode (LED) with 355 nm wavelength, and a visible luminescence map on the sensor pixels is projected onto a charge-coupled-device (CCD) camera. Thermal images of human were successfully obtained by using a 76 × 98 imaging sensor array with a carefully designed IR optics. The noise analysis shows that the noise-equivalent temperature difference (NETD) of the system is about 1.8 K.
- Infrared thermal imaging
- Vacuum deposited luminescent phosphor
ASJC Scopus subject areas
- Mechanical Engineering
- Electrical and Electronic Engineering