Optical scanner

A system for controlling the operation of an optical scanning mechanism for reading encoded indicia on a record member upon movement of the record member past the scanning mechanism comprising:

• a checkout counter having a horizontal supporting surface including an aperture for supporting a merchandise item having a record member located thereon;
• an optical scanning mechanism mounted within said checkout counter adjacent the aperture for projecting scanning light beams through the aperture when operated;
• a fluorescent lamp member positioned above the supporting surface of the checkout counter for directing radiant energy perpendicular to the supporting surface;
• a first silicon photodiode mounted in the supporting surface of the counter upstream of the aperture and in the path of movement of the merchandise item, said photodiode receiving the radiant energy from said fluorescent lamp member for generating a first control signal in response to the positioning of the merchandise item over said photodiode;
• circuit means coupled to said first silicon photodiode and said scanning mechanism for initating the operation of said scanning mechanism in response to the generation of said first control signal;
• and
• a second silicon photodiode mounted in the supporting surface of the counter downstream of the aperture and in the path of movement of the merchandise item, said second photodiode coupled to said circuit means and receiving the radiant energy from said fluorescent lamp member for generating a second control signal in response to the positioning of the merchandise item over said second photodiode whereby said circuit means disables the operation of the scanning mechanism in response to the generation of said second control signal.