Fig. 4. Demonstrations of the olfaction interfaces.

a A demonstration of the skin-integrated Device 1 in displaying olfaction feedback for providing an immersive experience to users during movie watching. Here, a girl in the movie is smelling a flower with the decreasing distance between the flower and her while the watcher could smell a more and more intense floral odor by wearing the olfaction interface. Here, OCL demonstrates the odor concentration level ranging from 1 to 3, corresponding to the low, middle, and high levels (iv). b A demonstration of the face-mask based olfaction interface in providing an alternative communication method, smell messages, for the disabled without the capability of vision and audio. By training users to link odors to specific information, the disabled users could efficiently communicate with others. c A demonstration of the Device 2 in assisting users to control their emotions as some specific odors could recall different human emotions. Here, all volunteers involved in the emotion reaction test are verified in normal emotion range (cii and ciii). d A potential demonstration of the Device 2 for helping amnesic patients recall lost memories as odors perception is modulated by experience, leading to the recall of emotional memories. e Demonstration of the wireless olfaction interfaces in real time interaction between the user and a virtual subject for walking in a virtual garden surrounded by various fruit fragrance. By programming the Device 2, 9 OGs insides the device could work independently (eii), or work together (eiii).