I was using the interference or moiré pattern to modulate the picture-plane of my paintings spatially. When I read about holography in a newspaper in 1967 it seemed a natural next step to use the interference pattern of light to make a hologram. Interference Box was shown in my first solo exhibition in 1969, and it became the best known of my pioneer works at that time, perhaps because the British information services issued a good official photograph of it.
The hologram shows an image of an open box, with a representation of an interference pattern on the back surface. In front of this is a piece of glass with pattern of straight lines printed on it. When you move back and forth in front of the hologram the straight lines animate and interact with the more complex pattern on the back of the box. The visible subject-matter of Interference Pattern Box referred to it's hidden structuring.
A hologram is recorded with an interference pattern of light waves too small to see with the naked eye. I was fascinated by the idea of infinite regress and self-reference, of overt and hidden interference patterning mirroring each other back and forth, endlessly.
In my first exhibition in 1969 I stood a small lens close behind the hologram, in between the laser and the hologram plate. This made a tiny, completely dimensional, smaller sized image of the whole hologram within the larger hologram, which reminded me of the mirror in the painting by Van Eyk of Jan Arnolfini and his wife. This sort of improvisation is possible because the whole picture is recorded in every part of the hologram when the hologram is made.
But I found that because people had never seen holograms they were confused about what they were looking at, or even what they were looking for, sometimes being unable to find the image at all without guidance. So I decided that this approach was self-defeating, and began to use more familiar subject-matter and a range of different approaches to explore the new medium.