Workpiece transfer apparatus

A workpiece transfer apparatus comprising:

• a nozzle unit having a central axis and including
• a tubular body having opposed first and second ends,
• a first suction hole opening at the first end of the tubular body,
• a transparent end face member sealing the second end of the tubular body, and
• a second suction hole opening in the tubular body and joined to a suction pathway connected to a suction device;
• an imaging unit having a central axis, positioned above and opposite the transparent end face member, and including
• a lens,
• a half mirror that is oblique to the central axis of the imaging unit, and
• an imaging element capturing an electronic image in response to light incident on the imaging element, wherein
• the half mirror is disposed between the lens and the imaging element, and
• the central axes of the nozzle unit and the imaging unit are co-linear;
• and
• a lighting device including a light source located outside the imaging unit and producing a light beam that is incident on the half mirror, wherein the half mirror directs the light beam along the central axis of the imaging unit toward the first suction hole, through the lens, to illuminate a surface of a workpiece in contact with the first end of the tubular body and held at the first suction hole, by suction, and transmits light reflected from the surface of the workpiece held at the first suction hole, through the lens, to the imaging element, to form and capture an electronic image of the surface of the workpiece.