ABSTRACT
CONTENTS 7.1 Introduction ................................................................................................. 112 7.2 Recording Very Low Intensity Diffraction Pattern
by a Photographic Plate .............................................................................. 113 7.3 Recording Very Low Intensity Diffraction Patterns
by a Photoelectric Detector ........................................................................ 116 7.4 Photoelectric Detection and Photon Counting Along
a Diameter of the Diffraction Pattern ...................................................... 121 Discussion ............................................................................................................ 123 Acknowledgment ................................................................................................ 125 References ............................................................................................................ 125
There continues to be a common belief that the registration of single photographic grains or emission of single photo electrons at a time validates the assertion that the interference and diffraction patterns are built through the contribution of individual photons (hν). A careful analysis of the past literature indicates that these experiments actually were not able to ascertain that one photon at a time interacted with the photo detector. This chapter reviews a series of experiments carried out during the early eighties, which suggest that the simultaneous presence of multiple photons (multiple units of hν) makes possible the registration of a single photographic blackening spot or the emission of a single photoelectron. The congruency with the paradigm of “waveparticle duality” is now better maintained by assuming that the photons, after they are emitted and then propagate from the source, develop the “bunching” property, which we proposed as a “photon clump” in 1985 and explained with a plausible extension of the Heisenberg’s Uncertainty Principle.
