Where are the Reference and Object beams in a Single Beam Reflection Hologram?
Single Beam Reflection (SBR) holograms are actually made with two beams. In a SBR Hologram the light travels to the film and we will call this light B1B2. Some of this light travels through the film. This is just the B2 part of the B1B2 light. It illuminates and reflects off the object back to the film. This is the object beam. This B2 light interferes with the B1 part of the original B1B2 within the film thickness. This creates a standing wave pattern thus the fringes or hologram. So there really are actually two beams used to create the hologram in a Single Beam Hologram.
