Recent reports on thermography based techniques for skin cancer diagnosis.

S. no	Device used	Description	Merits	Demerits	Acc, Se, Sp	Ref.
1	Image sensing device 340–380 nm	Using image sensing device illumination of ultraviolet light in the wavelength range of 340–380 nm, fluorescence property of the different skin anomalies were detected	Real time recording can be done and non-invasive	Highly expensive	—	205
2	Infrared camera	Infrared imaging takes place in different region of the tissues, which is caused due to micro calcification or calcification in the benign lesion	High resolution	Skin temperature varies for external noise that affects the result	—	206
3	Infrared thermometer	Thermal sensor that detect the affected area in a thermal map and calibrated using the processor (30) and corresponding output signals taken over a predetermined range of ambient temperatures	High resolution	Cost is high	—	207
4	Infrared detectors	Temperature distribution of the body surface is performed using infrared thermography which produces thermogram that further used for diagnosing procedure	High resolution	Emission from other surfaces affects the measurement accuracy	—	208
5	Amber radiance 1 T IR camera	Differentiation of melanoma and benign cutaneous lesions is performed using infrared thermography and found the sensitivity and specificity for different depths of the lesion	Real time recording and non-invasive	Need optimal instrumentation setup	Se: 39% Sp: 100% (0–5 mm lesions), Se: 58% Sp: 98% (lesions >5–15 mm), Se: 95% Sp: 100% (lesions >15–30 mm), Se: 78% Sp: 89% (lesions >30 mm)	209
6	Infrared thermal camera operated at 3 μm −5 μm	Thermal responses for healthy and malignant tissue were compared and concluded that increased metabolic activity of melanoma lesion can be detected using infrared imaging	High resolution	Camera has only 2% of accuracy	—	19
7	Infrared thermal camera operated at 14 000 nm	Symptoms of illness are detected using embedded devices which can be in the form of watch, glass, camera etc. Communication interface is attached to the embedded device so that the captured data is transferred into the local server of the hospital or other healthcare station	Automatically the captured data's are transmitted.	Cost is high.	—	203
8	Infrared camera	Thermal imaging for early stage detection of cutaneous melanoma is performed and resulting surface temperature oscillations were recorded using infrared camera	Real time recording	Lower rate transmission	—	210
9	Electrochemical sensor, optical sensor	Biosensors are used to detect specific biological analyze later by converting a biological entity into an electrical signal and analyzed. Biosensor has vast potential in detecting the cancer cells	Have more resolution comparing to other application sensor	Specific chemical analyzer is random in nature so difficult to interpret	—	201
10	Nd:YAG laser at 532 nm	The imaging sensor is use to capture the affected area which has 7.4 μm pixel pitch, composed of 1000 by 1000 imaging elements with a nanowire optical filter	The signal to noise ratio is high and consume less power	Cost is high since nanowire fabrication is implemented	—	204
11	Anon contact IR temperature sensor at 8–14 μm	The emitted IR range extends from 800 nm to few hundred micrometers which are detected for the temperature variation	Mapping of temperature variation is perfect	Resolution is less	—	211
12	Infrared detectors	The surface the sample is sensed with the small change in the motion. This motion is detected by bending of cantilever in the sensor system. Such system provides information about the position of the subject and the temperature value during displacement	Nanoparticles are synthesized in the sensor which makes the accuracy to be good	Cost is high	—	212
13	IR absorbance sensor at 3300 nm and 3570 nm	Infrared absorbance sensor used to detect the malignant cells in the biopsy. It takes 8 seconds to identify whether it is tumor or normal cell	This sensor is used in diagnosing the melanoma during histopathological analysis and also decreases the wrong interpretation	Supports shorter range and its performance degrade with longer distances	—	213