Patent ID: 7763789

Claim:
A non-contact drum tuner for providing tuning information for tuning a drum without making physical contact with said drum, said drum having a vibrating membrane, the tuner comprising: a light source for emitting modulated light onto the said vibrating membrane; a modulator to modulate said light source; a light detector for detecting reflected light, wherein said light detector receives a combination of reflected said emitted modulated light and ambient light; an ambient light rejection system coupled to said light detector to preferentially detect said emitted modulated light and to reject said ambient light; an amplifier coupled to said ambient light rejection system for amplifying a signal from said ambient light rejection system; tuning indication means coupled to said amplifier for providing tuning information responsive to said amplified signal; and wherein said ambient light rejection system comprises a demodulator coupled to receive a signal from said amplifier and a detector coupled to an output of said demodulator and having an output coupled to said tuning indication means.