Touchpad, Tenji, and Tactile Cues
Detail of the T400s tactile cue feature
Touchpad texture has gone relatively unnoticed in the world of ThinkPad design, and perhaps the industry in general. TrackPoint fans still wonder why we include a pad at all, and would not likely contemplate the advantage a texture could create for those who use them. If you are a pad user, and there are a lot out there, you know that the feel of the pad and the boundries of the pad are both important considerations. No pad user wants to look to find the pad, they want to feel it while looking at the screen. The desire to thin down the T400s required us to use a totally flush pad. That means no raised borders to define the active area. We were literally on the hunt for fractions of a millimeter. Even the X300 pad was allowed to be recessed by a fraction of a millimeter. This flush requirement neccesitated that we needed to create a new tactile means of locating the pad and its boundries.
The texture we introduced on the T400s was inspired by several things. One of them was the innovative yellow paving blocks used in Japanese train stations and sidewalks to guide or warn visually impaired pedestrians. Every time I visit Japan I am intrigued by these blocks. The square Tenji block system was invented in Japan by Seiichi Miyake in 1965 and first used in Okayama City in 1967. The oblong raised pattern indicate places, and in what direction, it is safe to walk confidently. The "warning" blocks with the round raised dots indicate edges, corners or other places where greater care or caution is required. The tactile cues developed for these unique blocks help everyone stay clear of train platform edges, crosswalk dropoffs, and other related hazzards. Sighted or not, it's really quite amazing how well these blocks work. You can easily discern the difference without looking.
Tenji paving blocks in a Tokyo train station
We studied a tremendous number of seemingly identical design variants of the dotted texture before we decided on the final version. Bumps varied by diameter, height, spacing, gloss, and even hardness. Every sample was evaluated by appearance and feel criteria. One test was to compare the surrounding palmrest texture to the pad samples to ensure that you could detect when your fingers moved beyond the pad boundries. We always did this with our eyes closed and then open. We also wanted to make certain the texture was pleasing to touch and look at. Many alternatives were rejected because they were too flashy looking, felt like sandpaper, or just made people giggle. In case you are wondering, we never considered making the pad yellow.
Sampling of prototype tactile samples
As the product got closer to release we were also able to test the texture with multiple users for extended periods of time. The feedback we gathered was very positive. They were able to detect the border easily and often commented that the subtle texture gave them a sense of precision as they moved their finger across the pad. The bumps provide indication of distance travelled and speed of movement. We found this effect to be of particular interest with multitouch gesture input. It's always rewarding to see our efforts noticed in the media and product reviews. Even more fun if the comments are positive. Nilay Patel at Engadget recently reviewed the T400s and loved the product and the touchpad design. This is my favorite quote from the review.
"a new texturized multitouch trackpad that's one of the best we've ever used. Seriously. In contrast to the hyper-smooth glass pads found on the MacBook Pro, the T400s's pad is covered in tiny nubs, which feel amazing under your fingers and make gestures like pinch-to-zoom feel more precise, even if they actually contribute nothing. It's pretty great -- we wish all trackpads were like this."
I hope you liked reading about how we developed the new touchpad texture, and that you like the resulting design. I intend to keep sharing stories like this one about how we created the T400s design updates. Keep watching Design Matters for updates over the next few weeks.