photoelectric switch is used to detect the presence or absence of a detected object on the manufacturing premise, as for example, in a production inspection step. The demands for the manufacturing premises to make industrial products, such as miniaturization, manufacturing cost reduction, quality improvement, etc., are increasingly severe with each passing year. In such an environment, the performance required for various sensors or switches is also becoming higher and the demands for higher functionability stronger. The demand for saving space affects the photoelectric switch and additional miniaturization of the electric switch is always needed.

Some known photoelectric switches in the related arts comprise a display section. In this kind of photoelectric switch, for example, while a threshold value is displayed, a switch or a button can be pressed to finely adjust the setup threshold value.

When a large number of functions are set or adjusted, the number of times a button or a switch is operated is increased to display information concerning the setting or adjusting. If the spacing between adjacent buttons or switches becomes narrower with miniaturization, the problem of erroneous operation is always involved. Once an erroneous operation is performed, to start again from the beginning, a button or a switch is repetitively pressed to return to the initial display item and further a button or a switch must be pressed multiple times to return to the problem display item. This extremely burdensome work is forced on the user.

It is a second object of the invention to provide a photoelectric switch which makes it possible to reduce the number of times a button or a switch is pressed to adjust the photoelectric switch while displaying multifunctional data.

It is a third object of the invention to provide a photoelectric switch that would appear to the typical user as if it were limited to the frequently used functions of operation even though the photoelectric switch would be, in fact, multifunctional.

The above-mentioned objects can be achieved by a multifunctional photoelectric switch having a display section, according to the present invention, wherein information concerning the photoelectric switch can be displayed in the display section and the display contents of the display information can be changed or adjusted. The photoelectric switch comprises: a display section for displaying one of a first display information and a second display information, the first display information including a plurality of items concerning a threshold value, the second display information including a plurality of items concerning functions of the photoelectric switch; a switch for switching information to be displayed on the display section between the first display information and the second display information, and wherein when the second display information is displayed on the display section, only a part of the plurality of items or all of the plurality of items in the second display information are sequentially displayed on the display section.

Further, in the above-mentioned photoelectric switch, it is preferable that the user can select some of items or the all of the items in the second display information to display the selected items on the display section. When the choice, some of the items, is selected, only some functions of the photoelectric switch are displayed. The items related to the basic operational settings of the photoelectric switch and/or relatively frequently used items may be adopted as the items displayed in the choice, some of the items.

On the other hand, if the user has extensive knowledge of a photoelectric switch and can fully use the photoelectric switch, he or she can display all items in the display section of the photoelectric switch for setting or adjusting all of the functions of the multifunctional photoelectric switch as the user desires.