Patent ID: 8064116
Filing Date: 2011-11-22
Classification: G03H

Abstract:
1. A method of forming a volume reflection hologram in a holographic recording medium, the medium being transparent or partially transparent and having a first side and opposite to the first side a second side, the method comprising the steps of: i) providing a coherent source of optical radiation; ii) directing the optical radiation towards the recording medium so that said optical radiation is incident on said first side, at least some of said incident radiation being transmitted through the recording medium to exit as exit radiation from said second side along an optical axis; iii) redirecting at least some of said exit radiation as redirected incident radiation back towards said recording medium so that said redirected incident radiation is incident on said second side, at least some of said redirected incident radiation being transmitted through the recording medium towards said first side, said incident radiation and said redirected incident radiation thereby intersecting at an obtuse angle to create at least one interference pattern within the optical recording medium; iv) creating from one or more of said interference patterns a volume hologram in the recording medium; wherein step iii) comprises the steps of: v) first directing the exit optical radiation away from the optical axis; and then vi) directing the exit optical radiation back towards the optical axis and said second side so that said redirected optical radiation is incident on the second side at an obtuse angle to the optical axis.