초록 ▼

An improved leak detection system (10) of the differential absorption type is provided for identifying gas leaks in a test object (12), wherein the improved system (10) provides enhanced resolution and accuracy by compensating for the effects of background gases and the like along the image path. Th

An improved leak detection system (10) of the differential absorption type is provided for identifying gas leaks in a test object (12), wherein the improved system (10) provides enhanced resolution and accuracy by compensating for the effects of background gases and the like along the image path. The system utilizes a video camera (18) to generate images of the test object (12) which has been pressurized with a selected gas (14) having strong absorption properties with respect to an illuminating light source (16) of a selected wavelength. Since the absorption bandwidth of the test gas (14) varies with temperature, the gas is preconditioned as by heating such that the temperature of gas leaking to the exterior of the test object (12) will vary with proximity to the test object. The camera (18) observes the pressurized test object in sequence through filters (30, 32) of narrow and broad bandwidth to generate a pair of images which can be electronically compared to isolate upon the test gas (14) located substantially at a specific leakage site or sites on the test object.

대표청구항 ▼

A leak detection system for identifying gas leakage from a test object, said system comprising: means for charging the test object with a test gas having relatively high absorption characteristics with respect to light of a selected wavelength, said test gas being temperature conditioned to a temper

A leak detection system for identifying gas leakage from a test object, said system comprising: means for charging the test object with a test gas having relatively high absorption characteristics with respect to light of a selected wavelength, said test gas being temperature conditioned to a temperature level significantly different than ambient; means for illuminating the charged test object with light having a wavelength corresponding generally with the selected wavelength; a pair of filters adapted to permit passage of light corresponding generally with said selected wavelength, said filters having relatively narrow and relatively broad bandwidths, respectively, and thereby defining a narrow band filter and a broad band filter; camera means for imaging the charged test object respectively through said narrow band filter and said broad band filter, and for respectively generating a narrow band image and a broad band image; and image processor means for comparing said narrow band image and said broad band image to identify gas leakage from the test object.