A display apparatus for a user interface of a medical instrument avoids erroneous input of numerical values when a user inputs information. A display apparatus includes a numerical value information input section, a selectable target information display section, and a target selection section. A plurality of the setting information selection sections are displayed to be associated with corresponding selectable target information, and a plurality of pieces of selectable target information are arranged so as to be adjacent to each other based on a same standard. The numerical value information input section corresponding to the selected target selection section is displayed simultaneously on a same screen. A range of the selectable target information is changed visually and displayed in response to the numerical value information which is input to the numerical value information input section.
