Abstract

Holographic optical elements (HOEs) have been widely used in various applications, such as collimating a beam from a laser diode and coupling light into an optical fiber. However, typical HOEs, because of their diffractive nature, suffer from severe chromatic aberration that imposes a strict requirement on the laser diodes and the environment in which they operate. The effect of chromatic aberration is more severe for HOEs with small f-number. This problem was addressed by using the recently developed radially symmetric iterative discrete on-axis (RSIDO)¹ encoding method. For example, one HOE was designed for a 13 nm optical wavelength range that corresponds to 0-60°C temperature fluctuation. For an eight phase level HOE with an f-number of 1 a diffraction efficiency of 78% has been achieved in computer simulations with small efficiency variation within the specified wavelength range. The HOEs have been fabricated, and the experimental results will be compared to those of the simulations.

© 1992 Optical Society of America