minimum to prevent mechanical bounce a timing delay is inserted if the sensor reaches its critical threshold too early the timing delay is reset and firing is inhibited as the user starts to pull the trigger 10 the signal from the optical sensor 18 starts to increase the user then continues to pull the trigger 10 until the signal from the optical sensor 18 rises above a preset maximum level to complete initiation of the firing cycle however the user must hold the trigger 10 for sufficient time to complete initiation of the firing cycle a second timing cycle is calculated to ensure that the user has held the trigger 10 for sufficient time and is not relying on mechanical bounce if the user releases the trigger 10 prematurely the second timing cycle will reset after the firing cycle has initiated the user begins to release the trigger 10 which subsequently allows the sensor 18 level to drop below its preset minimum level the firing cycle can now be repeated therefore it can be seen that the present invention provides a unique solution to the problem of providing a switching mechanism for a device that includes both the tactile feel of an electrical switch and the accuracy and reliability of an optical sensor switch moreover the mechanism of the present invention is user selectable which allows the user to choose the mechanism that he or she finds most desirable in addition the undesirable trait of u2018 mechanical bounce u2019 can be eliminated it would be appreciated by those skilled in the.