Olfactory Displays
The field of olfaction remains one of the most underdeveloped technological areas in our modern digital world. While significant advances have been made in the ways we receive digital information through visual and auditory channels, olfaction still feels like a technology of the future. This is likely due to a combination of factors, including the dominance of other senses, limited training in olfactory perception, and a perception that smell is less important. Yet olfaction has the unique ability to enrich visual experiences and engage areas of the brain associated with long-term memory.
The potential applications for olfactory technology are wide-ranging, spanning medical, educational, and entertainment domains. For example, olfactory cues could help reduce anxiety and stress or support the diagnosis of degenerative disorders such as Parkinson’s disease. In museums or tourism environments, carefully designed scents can complement audio-visual displays to recreate historical experiences. Other applications include virtual reality and multimedia, enhancing gaming, television, and interactive entertainment.
Given these possibilities, it is surprising that olfactory displays are not yet commonplace. One major reason is the lack of simple, robust, digitally controlled olfactory technologies. Unlike traditional approaches such as air fresheners, perfumes, scented paper strips, or candles, these modern systems are designed to deliver a controlled range of olfactory experiences in a digital format.
There have been numerous attempts to create such digital olfactory displays. Early examples include the AromaRama cinemas of the 1960s, which released scents from auditorium seats, and Morton Heilig’s Sensorama, the first full VR system. Neither achieved commercial success, and olfactory experiences were largely limited to scratch-and-sniff cards until the late 1990s. Subsequent efforts have also faced challenges in achieving widespread adoption.
In response to the lack of commercially available technologies, our group has developed simple olfactory displays that can be easily constructed and adapted by other researchers.
Rose Olfactory Display
The Rose Olfactory Display is an interactive scent system displayed at Shakespeare's New Place, designed to deliver rose fragrances that would have been present in Shakespeare's garden with precision and control. Created to enhance sensory engagement in exhibition spaces, it enables visitors to explore four distinct rose perfumes, each diffused on demand. The handcrafted wooden cabinet houses four red buttons on its top panel, each corresponding to a different rose variety. Pressing a button gently releases the chosen fragrance for ten seconds through a stainless steel outlet, inviting visitors to lean in and compare scents at their own pace. This simple, intuitive design makes the display ideal for immersive public experiences as well as research use.
Inside the cabinet, a compact electronic control system ensures accurate scent delivery. Four pumps and valves, each paired with a perfume-infused sponge in a glass jar, are activated by the control board. When triggered, a clean stream of air carries the selected aroma to the outlet, ensuring consistency and preventing cross-contamination between scents.
More information on this display can be found here.
For any queries regarding a similar project, contact Prof James Covington: J.A.Covington@warwick.ac.uk.
Liquid-Based Olfactory Display
Our group has previously developed and published two olfactory display units, both based on a thermal release mechanism. The first device used heated essential oils to generate a cloud of aroma, which was then dispersed by a small fan. The heating element consisted of platinum wire coiled inside a capillary tube and placed within a glass vial. The entire system was fully computer-controlled via a portable device, such as a tablet, using wireless communication. The unit could be loaded with up to eight different aromas, each of which could be used multiple times. The completed device was roughly the size of a Bluetooth speaker. A photo of the unit is shown below.
Wax-Based Olfactory Display
A more recent olfactory display uses Peltier heating elements and wax as the aroma carrier. The unit is fully computer-controlled and can hold up to 12 aroma capsules, each containing a distinct scent. These capsules can be activated individually or combined to create richer olfactory experiences. The device is larger than our original unit, roughly the size of a larger Bluetooth speaker. It was developed as part of a wine aroma game aimed at promoting sensory training. In testing, the portable device was evaluated with 15 volunteers to measure the detection and recognition times of six aromas associated with red and white wines. An overview of the unit is shown below.
The Future of Olfactory Displays
We are currently developing the next generation of olfactory displays, which will be showcased here once they are published. We are also exploring a wide range of applications for these devices.
For more information about our olfactory displays, please contact Prof James Covington:
J.A.Covington@warwick.ac.uk.