Oba: The prototype was quite polished and made a hit at the presentation, but oddly enough, making users aware of how the Intelligent Presence Sensor is working proved tricky. The picture fades out when no one's watching. Once you look at the screen again, the picture is back on before you know it. In other words, the better this feature works, the less you're aware of it. That was our dilemma. As it stood, people wouldn't get a tangible sense of how they're saving energy.
Mori: That's why we took the time to prepare a demonstration in the settings menu. By seeing a demonstration and a graph, which illustrate how it works and how it saves energy, you gain a new appreciation of the feature.
Activate the demonstration, and the estimated energy consumption is graphed on the bottom of the screen. The graph tracks energy consumption from 20 seconds ago to the current moment, in real time. This introduces the function, shows how effective it is, and simplifies choosing a mode that suits your viewing habits.
We also decided to show a live feed from the camera sensor in the demonstration. Including a camera in the first place was a delicate matter that raised privacy concerns. That's exactly why an open, honest demonstration should reassure owners. In the demo, you see what the camera sees, in a picture-in-picture display in the lower-right corner. Of course, the camera used by the Intelligent Presence Sensor never records or transmits any images. After all, that's why the system is called a sensor, not a camera.
Sakai: How well does the feature help save energy? To check performance, I installed a camera sensor on my set at home and investigated how we were watching TV. We happened to watch sports that evening, and I later discovered that the screen was on only about 30% of the time and off the rest. Of course, you'll pay more attention when playing video games or watching a movie, but the point is that you may not be watching as attentively as you think. It surprised us quite a bit. We wanted to present real viewing data directly, so we designed the on-screen display to include a graph showing the data.