Fukasawa : "Ambience", which places importance on the atmosphere of everyday life, rather than on the product alone. If the presence of this air quality improvement machine is overwhelming, the product itself will be considered pollution. (Laughs) That is why I wanted to create something that can be assimilated smoothly into that environment. This meant eliminating to the greatest possible extent elements that would disrupt the relationship between the product and its environment. Venetian blinds on windows consist of horizontal slats that blend quickly into the atmosphere. In the same way, I wanted to create a product that consists only of the texture of the louvers.

Fukasawa : It's easy to imagine dirt collecting in the corners of a room. There is also the human tendency to want to put things in corners. Although I personally don't place things in corners, most people start by filling the corners with things. I anticipated increased user satisfaction if the product can fit snugly in a corner.

Instead of positioning the air purifier parallel to the wall of the room to draw in air from all around, taking air in from one place in the corner makes you feel that all the air in the room is being drawn in. So I felt that the back corners should be cut off to fit into the 90-degree corner of a room.

Fukasawa : Yes, right from the beginning.

I worked on what people would think and how to reflect that in the simplest form possible. Although putting it into concrete form is the hardest, the inspiration is strong.

Fukasawa : There is a box-shaped fan structure inside the air purifier. The designer and product designer know immediately how large it will be. So, I say "cut off the corners", knowing fully well that I will be told that the fan won't fit inside if the corners are cut off. (Laughs)

Still I say this, and it surprises everyone. I say again that "it's good to cut off the corners, right?" Then their response changes to "it certainly is". By becoming the catalyst in convincing both the people who manufacture the product and the people who use it, prompting and spreading this idea among many people, I am able to build a consensus.

Fukasawa : I thought that the user would want to change the HEPA filter as soon as it becomes dirty. To replace it, the user would want to remove and insert the filter from the top. I thought of how the filter could pop out like film in a Polaroid camera and planned a large rectangular opening on the top, something resembling the videocassette slot in the old VCR.

In reality, however, people only need to replace the HEPA filter once every two years. (Laughs) Since the filter is there anyway, the basic idea was retained for easy removal and insertion.

Fukasawa : Exactly. I went on to suggest we should design the filter itself as well. It was then that I came up with the idea of making the filter pop out automatically when it needs to be replaced. I thought that would be fun. The filter being released when it's time to replace it.

Fukasawa : Like a toaster. In the discussion, I was told that would be interesting, but the pop-up will take place only once every two years. (Laughs)

Fukasawa : Discussion at that time also turned towards the business model, with ideas such as the OS notifying the user via their smartphone that the replacement date is approaching before the filter pops up. After looking into IoT, I suggested servicing that involved communicating with the air purifier, with automatic delivery of the filter. I thought that a filter business of that kind would be profitable. We ended up scrapping the idea at the review because the filter does not need replacing so frequently.

Fukasawa : Since the people at Hitachi I speak to in meetings are also in the creative field, some brainstorming begins with people juggling such ideas. Because we must consider aspects of practicality, there are ideas that are not accepted as planned. Still, I do not let go of ideas that should be kept. Especially ideas that are key to the design.

Fukasawa : If the display and operation panel constantly blink, they become irritating. Because light in a dark room is a kind of noise, the panel was designed to show only the switch that is being touched.

On the air-quality status display, the air quality is shown by a change in colour. Blue light means that the air is clean.

Normally, interface design refers to the design of the operating panel and display. However, I see the whole product as the interface. That is why designing user interaction means designing the product. I simply explore the interaction between the product and the user and the product and its environment through hardware. I believe that making the façade entirely of louvers is a form of interface. The filter popping out is also an interface. So are the display and operating panel. A product is an interactive object. That is why designing the product is the same as designing an interactive interface.

This is something that I continue to tell Hitachi in our discussions. Product as interface. We are not hardware designers but interactive designers.