A brief timeline to Esrille New Keyboard − NISSE from 1980's

Note this article is basically an English edition of my previous article written in Japanese.

This month, Esrille New Keyboard − NISSE with 17.5 mm key spacing (Size M) has been released in addition to the standard 18.8 mm key spacing model (Size L). Recently, Japanese ergonomic keyboards evolved since 1980's seem to be revisited very often by keyboard enthusiasts around the world.

NISSE Size M (front) and Size L

This article describes how Esrille New Keyboard − NISSE has been evolved from the TRON keyboard designed in 1980's in the TRON project.

BTRON and TRON Keyboard

In 1987, Panasonic showed their personal computer prototype running the BTRON operating system. The picture of the prototype can be seen in this article (in Japanese). BTRON operating system had supported multitasking and an overlay multi-window user interface. At that point, Windows 1.0 supported only a tiling-window user interface, and Mac OS had not supported true multitasking yet. The expectation for BTRON to be released was huge in the middle 1980's.

TRON keyboard

The design of the TRON keyboard attached to the BTRON personal computer was also remarkable. In Japan, people who could touch type were extremely rare in 1980's. The standard keyboards with 19 mm key spacing seemed to be too large for the average Japanese adult hand length to touch type. It was reported that only 15 per cent of college students could touch type even in 2014 in Japan.

TRON keyboard addressed these issues; key switches were more naturally placed, and production TRON keyboards were expected to be released in three sizes, S, M, and L without based on the one-size-fits-all mentality. The key spacing used with the M size TRON keyboard was only 16 mm.

In 1991, a production TRON keyboard, TK1, was finally released. It could be used with the BTRON personal computers that were also released late in 1991, and with NEC PC-9800 series personal computers that were very popular in Japan until early 1990's. Unfortunately, it was Size M only, and could not be used with Windows running on PC/AT compatibles, which were becoming quite popular even in Japan. The sale of TK1 was ended in 1996. In 2001, about 200 units of a new TRON based keyboard, ST-2000, was manufactured, which was the last TRON keyboard released so far.

Note a more conservative version of the TRON keyboard, named µTRON keyboard, is available since 2007.

M-type Keyboards

I should also mention about the M-type keyboards that had been sold from NEC since 1983 and for about 20 years. Dr. Masasuke Morita at NEC invented M-type keyboard in the early 1980s. Several pictures of M-type keyboards are collected in this page. As we can see, Dr. Morita had developed many common designs of today's ergonomic keyboards. The last M-type keyboard, named ergo-fit keyboard, was released in 1998, and said to be 20,000 units were manufactured a year.

A version of M-type keyboard (front) and NISSE

Tweaking the TRON keyboard

Due to the lack of products, I started making my own custom TRON keyboard since 2004. I guess keyboard geeks are eventually trying to make their own keyboards in any country. :-)

Unit #1 (2004)
The 1st one was basically a failure; PCB patterns had mistakes, and key switches are placed too high from the table. I had to use separate arm rests for using the 1st one.

Unit #2 (2005)

The 2nd one fixed the PCB patterns, and key switches were placed at lower positions by cutting the front corner edges of the PCB outlines. I don't have to use separate arm rests anymore. NISSE uses basically the same PCB outline design used in this 2nd one.

Unit #3 (2005)

The 1st and 2nd one used ALPS switches, which were slightly bigger to be used for a TRON Size M keyboard. The key spacing of the first two units was about 17.5 mm, which turned out to be too large for my hands with the TRON keyboard's switch layout. The 3rd one uses Cherry MX switches, which have a smaller form factor, with the standard 16 mm key spacing of the TRON Size M keyboard.

I used the 3rd one for about five years, and it still works fine. The long operating life of Cherry MX switches is quite amazing. The only issue I found with the 3rd one was the placement of key switches for pinkies. The pinky column angle didn't fit with my natural pinky movement, and was not very comfortable to touch type.

Unit #4 (2010)

I made the 4th one with 15 mm key spacing in 2010. I found this small keyboard comfortable with my hands. However, it used tiny tact switches, and I had to make a new one in 2013 as their operation life is not very long like Cherry MX switches.


The 5th one, which is now called NISSE Size L, uses the standard 18.8 mm key spacing. My goals were,

  1. to make it easy to migrate from the TRON keyboard,
  2. to employ Cherry MX switches again, and
  3. to minimize the construction time by using the standard 18.8 mm key spacing.

I have also tweaked the NISSE firmware so that it can handle several efficient Japanese Kana character layouts natively. NISSE supposed to be only my own 5th custom keyboard. However, because of this firmware, several Kana layout users contacted me if they can also use NISSE. It was the beginning of NISSE as a real product.

Note: Today, most Japanese people input Japanese characters using Romaji, basically typing one or two English characters that represent the sound of a Japanese Kana character for each Kana character. It is okay but maybe not optimal. Kids do not learn how to write Japanese in Romaji until the third-grade in elementary schools.
From late 1970's, several efficient Kana layouts have been studied including the TRON Kana layout. Thumb shift layout, developed by Yasunori Kanda and others at Fujitsu, was the most commercially successful one among those; it even took the word processor market lead in 1980's.
Unfortunately, most of the today's operating systems and IMEs do not support those efficient Kana layouts natively. When these Kana layouts are used with NISSE, the firmware of NISSE converts Japanese Kana characters into Romaji internally so that virtually any operating system and IME can be used with these Kana layouts.


NISSE Size L was basically designed to fit with the average hand length of Japanese adult male, about 183 mm, or longer. The average hand length of Japanese adult female is about 169 mm. So shrinking the key spacing to about 92 per cent would provide better usability for wider potential users in Japan. NISSE Size M uses 17.5 mm key spacing.

Green trace lines indicate the finger reaches collected in the TRON keyboard research

While the key spacing of NISSE Size M is 1.5 mm longer than that of TRON Size M keyboard, the required finger reaches are very close as illustrated in the above figure.
Note NISSE Size M key layout is not a micro-copy of NISSE Size L; key column angles are also tweaked a bit.

Small keycaps being machine milled

The challenge for releasing NISSE Size M is in the production of small keycaps that fit 17.5 mm key spacing. Since the number of NISSE Size M to be released is very limited, making new metal molds for keycaps was not a viable option. Instead keycaps used in NISSE Size M are machined milled by CNC milling machines from the standard 18 mm keycaps for 18.8 mm key spacing.


Perhaps it was sort of a lucky for Japanese computer manufactures and researchers that most Japanese people had no experience using keyboards including typewriters until 1980s. Re-inventing a computer keyboard seemed to be considered a right direction, rather than training people to use the existing computer keyboards evolved from typewriters. Even though the commercial results of both TRON keyboard and M-type keyboard didn't look very successful, the researches conducted during 1980's seem to be still valid and actually very interesting.

Releasing keyboards in three sizes was one of the goals shown in the TRON project in 1980's. Probably it is more crucial for ergonomic keyboards than the standard keyboards since more users lean their forearms on the table or arm rests during typing and finger reaches are more limited. Now NISSE is provided in two different sizes. Hopefully keycap makers would follow this direction too so that more keyboard makers can release their keyboards in multiple sizes much easily.


新キーボード プロジェクト? - NISSE Mサイズまでの長い道のり

エスリルでは、今月からキーピッチ17.5mmのNISSE Mサイズの受注を開始しています(標準的なキーボードのキーピッチは約19mmです)。手の大きさの個人差はかなり大きく、学術的には、毎日長時間使われる方も多いキーボードに関しては、"one-size-fits-all"という考え方によらずに、それぞれのユーザーの手の大きさにあった、特により小さなキーボードが提供されることが期待されていました。

NISSE Mサイズ(手前)とLサイズ

今回はキーピッチ17.5mmのNISSE Mサイズの実現に至るまでの道のりを少し長いスパンで紹介したいと思います。


1987年、松下電器(現Panasonic)からBTRONパソコンの試作機開発成功のニュースが流れました(実機の写真がこちらの記事に載っています)。この当時のBTRONへの期待感はものすごいものがありました。Windows 2.0の発売前で、オーバーレイ ウィンドウでマルチタスクのパソコンというだけでもすごかったのです。まだWindowsはタイリング ウィンドウ、Mac OSはシングルタスク、という時代でした。




それから20年近くたって、やっぱりTRONキーボードは使ってみたいなぁ、ということで、2004年の暮れに1台作ってみることにしました。キーボード マニアは最後は大体自作にたどり着くような気がします(笑)。






1号機, 2号機までは、ALPSスイッチを使っていたこともあって、キーピッチは17.5mmくらいになっていました(実物はもう残っていません)。TRONキーボードのMサイズは16mmで、17.5mmでは実際にやや大き過ぎる感じがありました。そこで、ALPSスイッチよりも寸法の小さなCherryのMXスイッチに変更して、キーピッチを16mmで作りなおしたのが3号機です。

この3号機は2005年から2010年まで使っていたのですが今でも問題なく動きます。Cherry MXスイッチの5,000万回という寿命はなかなかすごいものがあります。



問題はキーピッチかも、ということで2010年にキーピッチ15mmで4号機を作ってみました(ちなみにTRONキーボードのSサイズは14mmだそうです) 。ここまで小さくすると小指の違和感もなく、なかなか使いやすいものでした。ただコーヒーとかをこぼしたりしすぎた所為もあって(汗)、2013年には新しいものが必要になってきました(使っているスイッチが液体の侵入に弱く、ときどきスイッチを新品のものに交換して使ったりしていたのでした)。


実際に新しいキーボードを作るとなると結構時間を取られるので、他社のエルゴノミックキーボードを使ってみたり、自作3号機を復帰させてみたりしていたのですが、4号機の代わりとしてはどうも、ということではじめたのがこの「新キーボード プロジェクト?」でした。




ただ実際に作ることを想定すると既成品のない17.5mm用のキーキャップを作るのは大変、ということで標準の18.8mmでなるべく良いモノを、ということに方針を変更してできたのが新キーボードでした。「新キーボード プロジェクト」とラベルのついた一連のここのブログ記事は、もともとはこの過程をまとめていたものです。


これでまたMXスイッチの自分の手にあったキーボードができたと喜んでいたところで、Facebookの「親指シフト グループ」の方たちからお声がかかり、これはどうやらほかにも欲しそうな方たちがいらっしゃる様子、ということで「プロジェクト?」だったものを、本当の「プロジェクト」として進めて行くことにしました。





その後、NISSEは部品単価をより抑えられるように、プリント基板は4回、筐体も1回設計変更をして現在に至っています。ごく一部の方向けと思っていたNISSEも、FCC Part 15 クラスB機器としての要件をクリアして、アメリカまで届けるようなことになったのは、当初はまったく想定していなかった出来事でした。


今回、2015年6月から新たに提供をはじめたNISSE (Mサイズ)は、新キーボード プロジェクト開始当初に一番使いたかった、標準の18.8mmよりも小さな17.5mmのキーピッチを採用しています。エルゴノミック キーボードには興味があったのだけれど、実際に触ってみたら大き過ぎて手に合わなかったという経験がある方は、ぜひ一度NISSEのMサイズを試してみてください。



上の写真はNISSE Mサイズ(試作品)で手の長さは180mmです。日本人の男女合わせた手の長さの平均は178mmなので、比較的日本人の平均的なイメージに近いかと思います。

NISSEの場合の、ホーム ポジションへ手を置く手順は、

1) 右手の人差し指、中指、薬指、小指をJ, K, L, ;キーに、親指をスペースキーの上にのせる。
2) そのまま手を広げた時に、人差し指、中指、薬指、小指が6, 8, 0, =キーの方向に自然に伸びることを確認して、そのまま前腕を机(あるいはアームレスト)の上に置く。
3) 左手も同様になるように体とキーボードの距離なども合わせる。








キーボードに関しては、2013年にこんな感じモノが欲しい、と思っていたモノをNISSE Mサイズという形で実現することができました。実質的にはLサイズが5号機、Mサイズが6号機になりますが、必要な方には同じもの製品としてお渡しできるようになっている、というのはなかなか嬉しいことだったりしています。