Abstract

The pioneering work of Hanbury Brown and Twiss on intensity interferometry¹ was followed by that of Gamo² who proposed a triple intensity correlator arrangement to derive the phase of the coherence function. This method met with limited success because the expression of intensity correlation with three collectors provides only one relation for the two unknowns, namely, the cosine and the sine of the phase argument. Consider the possibility of having a very large square array of mirrors (each mirror is of the intensity interferometer type to concentrate light onto a detector; not of imaging quality). It is possible to show that by using triple and quadruple intensity correlations the cosine and the sine of the phase argument of the spatial coherence function can be determined for all possible mirror separations in the array. This coupled with the usual intensity interferometry which measures the square of the absolute value of the coherence function will allow us to invert the Van Cittert-Zernike result to derive the intensity distribution across an astronomical object.

© 1985 Optical Society of America