Diffraction properties of quasi-random pinhole arrays: suppression of higher orders and background fluctuations

Abstract

A transmission grating can be formed from quasi-random pinhole arrays. We show here that this type of grating can reduce the higher diffraction orders effectively when an appropriate arrangement is used. A simple but accurate analytical model is provided to describe the physical mechanism that is responsible for suppression of the higher orders, and this model is verified through numerical simulations. In particular, the background intensity enhancement and the fluctuations in this intensity that are introduced by the quasi-random arrangement of pinholes are also assessed. The consistent one-to-one match produced between the diffraction directions and the wavelengths means that this type of grating has considerable potential for use in spectroscopic measurement and monochromator applications.

Keywords:

• Higher-order diffraction suppression
• grating
• spectroscopy