초록 ▼

A photo-acoustic leak detection system for detecting a gas leaking from a component 30, includes at least two laser beams 24,26, incident on the component 30 and disposed so as to completely illuminate an inspection region 159 around at least a portion 28 of the component 30, each beam having a corr

A photo-acoustic leak detection system for detecting a gas leaking from a component 30, includes at least two laser beams 24,26, incident on the component 30 and disposed so as to completely illuminate an inspection region 159 around at least a portion 28 of the component 30, each beam having a corresponding wavelength .lambda..sub.1 which is absorbed by the gas, the gas emitting an acoustic signal 36 when the gas absorbs light from at least one of the beams, an acoustic sensor 40, which receives the acoustic signals 36 and provides a sensor signal indicative thereof on a line 42 to a bandpass filter 44 and a synchronous detector 18 which provide a filtered signal indicative of the acoustic signal 36 on a line 50 to a signal processor 52. The processor 52 provides an output signal indicative of the leak in the component 30.

대표청구항 ▼

[ We claim:] [1.] A photo-acoustic leak detection system, comprising:a beam incident on a component containing a gas, said beam having a first wavelength which is absorbed by said gas and a second wavelength which is not absorbed by said gas, said gas emitting a first acoustic signal upon absorbing

[ We claim:] [1.] A photo-acoustic leak detection system, comprising:a beam incident on a component containing a gas, said beam having a first wavelength which is absorbed by said gas and a second wavelength which is not absorbed by said gas, said gas emitting a first acoustic signal upon absorbing said first wavelength, said second wavelength producing a second acoustic signal;an acoustic sensor which receives said first and second acoustic signals, said acoustic sensor providing a first sensor signal and a second sensor signal indicative of said first and second acoustic signals, respectively; anda signal processor which receives said first and second sensor signals, said signal processor providing an output signal indicative of the existence of a leak in said component, said signal processor using said second sensor signal as a non-leak baseline measurement.