Automatic optical bright and dark stripe counter

The invention discloses an automatic optical bright and dark stripe counter which is simple in structure, low in cost, convenient to carry and operate and not influenced by light in testing environment and can effectively improve counting accuracy and reliability. The automatic optical bright and dark stripe counter consists of a signal generator and a counting display (formed by a signal processing circuit, a counting control circuit and a counting display circuit); the signal generator (the signal processing circuit) is provided with a voltage comparator U12 (U12A); the in-phase input end of the voltage comparator U12 (U12A) is connected with the emitter of a triode Q1 and is grounded through a resistor R6; the base of the triode Q1 is connected with a collector through a photosensitive diode GD1 and is connected with working voltage Vdd; the inverted input end of the voltage comparator U12 (U12A) is connected with the emitter of a triode Q2 and is grounded through a variable resistor R7; the base of the tr