The holo-lamp is a type of device which can make and relay three-dimensional, holographic recordings.
Arnold Rimmer of the JMC Red Dwarf carried such a device throughout most of his adult life (and most his death as a hologram), although he never played the recording on it. The message had been recorded on Io, in Arnold's youth three million years earlier, by the man Arnold believed to be his father. His father had given Arnold strict instructions to only replay the message when he had successfully become a high-flying officer in the Space Corps like his older brothers John, Frank and Howard. The message remained unseen, since Arnold had failed his astro-navigation exams eleven times, and was reduced to cleaning gunk out of the vending machines with Dave Lister on the Z Shift.
Three million years later, the hologram of Arnold Rimmer was trapped on Blue Midget with the other Dwarfers. Blue Midget was hiding in an asteroid belt from Simulant Death Ships and their Annihilators. Faced with (a second) death, and also due to some unexpected deep intuition from the Cat, Rimmer decided to finally move out of his father's shadow and watch the recording regardless.
In the holo-recording, Mr Rimmer proceeded to tell Arnold that he was not his biological father, who was actually Dungo Dennis, the "imbecile" family gardener. Lister commented that it was a billion-piece jigsaw puzzle coming together. Mr. Rimmer informed Arnold of his true parentage and told him that he would receive no more birthday presents. Instead of a family lineage in the Space Marines and French and Austrian royalty, Dungo's lineage was that of "lame-brain artisans and pram faced trollops".
Despite the revelation of his illegitimate status and lowly pedigree, Arnold was encouraged by this news. He had thus achieved everything by himself without help from Mr Rimmer. By his erstwhile father's standards, Arnold was a miserable failure and disappointment, but to Dungo he would be a terrific success. Dungo was a simple man who would take Arnold's exploits in space and low rank to be wonderful achievements. Psychologically freed of Mr. Rimmer, Arnold began to think of himself as a working class hero and managed to come up with a plan using the Molecular Destabilizer to save the Dwarfers from destruction. ("The Beginning", Series X)
- Rimmer feels so strongly for his holo-lamp that he brings it and nothing else during their evacuation, which makes one wonder why he did not bring it with him during the events of the Series III episode "Marooned"; though perhaps it was within the camphor wood trunk. It is also true that the hololamp could just be housing the hologram message file, and that he was not given the lamp itself.