Abstract: An apparatus and method for multi-spectral dual balanced imaging is provided. The apparatus includes: (a) a first member operable to produce from incident light a first band having first band wavelengths and a second band; and (b) a second member operable to produce from the second band a third band having wavelengths shorter than the first band wavelengths, excluding the first band wavelengths and having wavelengths longer than the first band wavelengths. The method involves: (a) producing from incident light a first band having first band wavelengths and a second band; and (b) producing from the second band a third band having wavelengths shorter than the first band wavelengths, excluding the first band wavelengths and having wavelengths longer than the first band wavelengths.

Abstract: An apparatus and method for multi-spectral dual balanced imaging is provided. The apparatus includes: (a) a first member operable to produce from incident light a first band having first band wavelengths and a second band; and (b) a second member operable to produce from the second band a third band having wavelengths shorter than the first band wavelengths, excluding the first band wavelengths and having wavelengths longer than the first band wavelengths. The method involves: (a) producing from incident light a first band having first band wavelengths and a second band; and (b) producing from the second band a third band having wavelengths shorter than the first band wavelengths, excluding the first band wavelengths and having wavelengths longer than the first band wavelengths.

Abstract: The invention relates to an imager system for imaging of a plume of a fugitive gas, dependent upon an electromagnetic wavelength absorption characteristic of the gas. A bi-spectral selector assembly houses first and second filters in separate first and second optical paths for transmittal of electromagnetic energies emanating from the scene of interest. The first and second filters have adjacent mutually exclusive narrow band pass characteristics only one of which corresponds to the electromagnetic wavelength absorption characteristic of the gas. An imager captures first and second image data having traversed the first and second filters in a frame which is then processed by correlating the image data to provide displayable data including an indication of any plume of the fugitive gas. The data is displayed in real time. In one example a CCD video camera provides picture data which is displayed with the image of the plume of gas pasted thereupon.