Japanese Keyboard Layouts

Intro to Japanese Writing System and Input Method

Japanese Input Method

Japanese Keyboard Layouts

There are many ways to arrange the English letters on keyboard. And there are many ways to arrange the kana on keyboard too. So, there are many different layouts.

Here is a summary of the different layouts:

QWERTY JIS

Romaji input. Qwerty layout.

Nicola (thumb-shift)

Kana input. 2 special Thumb-shift modifier keys. Kana with dakuten are typed by pressing the thumb-shift of the other hand. Qwerty layout for English.

M-System

Romaji input. Efficient layout. Home row keys are {E U I A O, K S T N H}.

JIS X6004

Kana input. Efficient kana layout. Use prefix shift. Dedicated dakuten key. Qwerty layout for English.

TRON

Kana input. Efficient kana layout. English layout is Dvorak. 2 special Thumb-shift modifier keys. Kana with dakuten are typed by pressing the thumb-shift of the other hand.

New Stickney Layout

Kana input. Use prefix shift. Dedicated dakuten key.

QWERTY JIS Layout

QWERTY JIS Layout is the most popular layout used in Japan. It is basically the same as US keyboard.

You use English letters to type kana, then press a key to convert previous kana to kanji if needed.

Every kana requires 2 keystrokes (2 English letters).

This is the least efficient method and layout.

For explanation of Japanese special keys, see Japanese Input Method

Nicola Layout (aka Thumb-Shift Layout)

In Nicola Layout (aka Thumb-Shift) layout:

• Each key corresponds to a kana character. The kana are arranged efficiently.
• Two special shift keys: left thumb-shift key and right thumb-shift key. Each is a independent modifier key.
• Only 3 rows are used for kana, each row has 5 keys per hand. So, left hand has 15 keys, right hand has 15 keys, total 30. Multiply by 2 thumb-shift keys, you have 90 possibilities, enough for all kana letters.

• When no thumb-shift is pressed, the lower labeled character is typed.
• When opposite hand thumb-shift is pressed, the lower labeled character with Dakuten ゛ is typed.
• When a thumb-shift of the same hand is pressed, the upper labeled character is typed.

Example:

• と (no shift) ⇒ と
• と + Other Hand Shift ⇒ ど
• と + Same Hand Shift ⇒ お

Note: this means, some character need to be typed using the same hand. This can cause hand strain and can increase risk of Repetitive Strain Injury.

Nicola became super popular in the 1980s, due to Japanese word processors, and still has great number of users.

Yasunori Kanda and others at Fujitsu developed Thumb-Shift layout in the late 1970s.

• 
  Thumb-Shift, 1980

M-System Layout

M-System input system:

• Use English letters to input Kana.
• English alphabet are arranged for kana efficiency. For example, left hand home row is {e u i a o}, and right hand home row is {k s t n h}. This latter is the order of kana.

M-System input system and keyboard was designed by Dr Masasuke Morita at NEC in 1983.

[see NEC M-System keyboards History]

JIS X6004 Layout

JIS X6004 is a very efficient layout.

It is kana based input. Each key types a kana directly.

The kana are arranged according to frequency and ease of the key-press position.

[see Japanese Character Frequency]

The Shift key act as prefix key. That is, press it, release it, then the next key press will be effected.

When Shift key is prefixed, a different kana is typed. (Left Shift and right Shift are not differentiated.)

A dedicated key is used for the Dakuten ゛. (it's on the L key)

JIS X6004 was a Japanese industrial standard Kana layout established in 1986 to amend various issues in the current, old JIS standard Kana layout. While its technical design was superb for professional typists, JIS X6004 was abandoned as a JIS standard in 1999 due to its unpopularity in the market.

JIS X6004 allows a shift key to be placed in the center of the keyboard where a space-bar is placed. Since white space characters appear far less frequently in Japanese than in English, the same typing method can be used both in Japanese and English with this JIS X6004 configuration.

We could see JIS X6004 as a Japanese Dvorak or Colemak layout, and the current JIS standard Kana layout as QWERTY. Today its superior technical design has been re-evaluated as it becomes easy to scan and analyze huge Japanese texts and n-grams using personal computers. Even though JIS X6004 is no longer a JIS standard, it is actually still in use and its variations are also being developed by the enthusiasts.

TRON Kana Layout (Dvorak)

TRON is a input system, a layout, and a special ergonomic keyboard.

TRON input system:

• Is kana input system. That is, keys correspond to hiragana directly.
• Uses Dvorak layout for English. [see Dvorak Keyboard Layout]
• kana arrangement is optimized for efficiency.
• Tron uses left shift and right shift to input different hiragana. The left/right shift are positioned for the thumbs.
• left/right shift is also used to input left/right brackets on the number row, and different punctuations on other keys.

The TRON Kana layout was developed by Prof. Ken Sakamura in the TRON keyboard sub-projects of the TRON project in the mid 1980s.

TRON Kana layout has a quite high efficiency regarding the number of required key touches to input Japanese texts.

• 
  TRON keyboard

New Stickney Layout

This is a new efficient layout.

• Kana input. The kana are arranged efficiently.
• Use pre-shift key. To press a shifted kana, press Shift, release, then press the kana key.
• A dedicated key for dakuten ゛. (on the L key) Press it after the kana. Example: か゛ → が

see https://esrille.github.io/ibus-replace-with-kanji/layouts.html

Thanks to the site http://www.esrille.com/keyboard/layouts.ja-jp.html for providing much info on this page.