| generation | 1st | 2nd | 3rd |
|---|---|---|---|
| Size |
 Size : 9.5cm × 2.0cm |
 Size : 4.0cm × 2.0cm |
 Size : 2.8cm × 2.1cm |
| expression method |
 Color changes (The readings are ambiguous, and customers avoid purchasing these products.) |
 A red window appears. (clear reading) |
| generation | Size | expression method |
|---|---|---|
| 1st |
Size : 9.5cm × 2.0cm |
Color changes (The readings are ambiguous, and customers avoid purchasing these products.) |
| 2nd |
Size : 4.0cm × 2.0cm |
|
| 3rd |
Size : 2.8cm × 2.1cm |
A red window appears. (clear reading) |
