Photoelectric switch device

A photoelectric device for detecting a presence or an absence of an object in a specified field of detection which has at least a photoelectric mechanism for receiving light from the field of detection and generating an electric signal of a level representing an amount of light incident thereupon and a processor for processing the electric signal from said photoelectric mechanism, for making a determination of a presence or absence of the object in the field of detection on the basis of a comparison of the level of the electric signal representing a result of the determination, said processor and said photoelectric mechanism being installed in a generally rectangular-parallelpiped box casing defined by a plurality of walls, said photoelectric device comprising:

• a lens adjacent to a front wall of said generally rectangular-parallelpiped box casing for directing light from the field of detection to said photoelectric mechanism;
• a display disposed adjacent a rear wall of said generally rectangular-parallelpiped box casing opposite to said front wall and operatively connected to said processor to display at least one of a specified threshold and a level of the electric signal from said photoelectric mechanism;
• an adjuster disposed adjacent said rear wall and operatively connected to said processor, said adjuster being capable of adjusting the specified threshold while the specified threshold is displayed on said display;
• and
• an indicator disposed adjacent said generally rectangular-parallelpiped box casing in an area confined by said rear wall and a top wall of said generally rectangular-parallelpiped box casing connecting said front wall and said rear wall to each other and operatively connected to said processor for indicating the result of the determination.