摘要 |
In a first display mode, a threshold value is numerically displayed on a first display section and the current light reception amount (current value) is numerically displayed on a second display section. In a second display mode, the tolerance value is numerically displayed on the first display section and the current light reception amount is numerically displayed on the second display section. To switch from the first display mode to the second display mode, a display mode change key can be operated. |